Fixed MTP to work with TWRP

drivers/char/hw_random/Kconfig

@@ -0,0 +1,402 @@
+#
+# Hardware Random Number Generator (RNG) configuration
+#
+
+menuconfig HW_RANDOM
+	tristate "Hardware Random Number Generator Core support"
+	default m
+	---help---
+	  Hardware Random Number Generator Core infrastructure.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rng-core.  This provides a device
+	  that's usually called /dev/hw_random, and which exposes one
+	  of possibly several hardware random number generators.
+
+	  These hardware random number generators do not feed directly
+	  into the kernel's random number generator.  That is usually
+	  handled by the "rngd" daemon.  Documentation/hw_random.txt
+	  has more information.
+
+	  If unsure, say Y.
+
+if HW_RANDOM
+
+config HW_RANDOM_TIMERIOMEM
+	tristate "Timer IOMEM HW Random Number Generator support"
+	depends on HAS_IOMEM
+	---help---
+	  This driver provides kernel-side support for a generic Random
+	  Number Generator used by reading a 'dumb' iomem address that
+	  is to be read no faster than, for example, once a second;
+	  the default FPGA bitstream on the TS-7800 has such functionality.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called timeriomem-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_INTEL
+	tristate "Intel HW Random Number Generator support"
+	depends on (X86 || IA64) && PCI
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Intel i8xx-based motherboards.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called intel-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_AMD
+	tristate "AMD HW Random Number Generator support"
+	depends on (X86 || PPC_MAPLE) && PCI
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on AMD 76x-based motherboards.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called amd-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_ATMEL
+	tristate "Atmel Random Number Generator support"
+	depends on ARCH_AT91 && HAVE_CLK
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Atmel AT91 devices.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called atmel-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_BCM63XX
+	tristate "Broadcom BCM63xx Random Number Generator support"
+	depends on BCM63XX
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on the Broadcom BCM63xx SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called bcm63xx-rng
+
+	  If unusure, say Y.
+
+config HW_RANDOM_BCM2835
+	tristate "Broadcom BCM2835 Random Number Generator support"
+	depends on ARCH_BCM2835
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on the Broadcom BCM2835 SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called bcm2835-rng
+
+	  If unsure, say Y.
+
+config HW_RANDOM_GEODE
+	tristate "AMD Geode HW Random Number Generator support"
+	depends on X86_32 && PCI
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on the AMD Geode LX.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called geode-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_N2RNG
+	tristate "Niagara2 Random Number Generator support"
+	depends on SPARC64
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Niagara2 cpus.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called n2-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_VIA
+	tristate "VIA HW Random Number Generator support"
+	depends on X86
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on VIA based motherboards.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called via-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_IXP4XX
+	tristate "Intel IXP4xx NPU HW Pseudo-Random Number Generator support"
+	depends on ARCH_IXP4XX
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Pseudo-Random
+	  Number Generator hardware found on the Intel IXP45x/46x NPU.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ixp4xx-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_OMAP
+	tristate "OMAP Random Number Generator support"
+	depends on ARCH_OMAP16XX || ARCH_OMAP2PLUS
+	default HW_RANDOM
+ 	---help---
+ 	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on OMAP16xx, OMAP2/3/4/5 and AM33xx/AM43xx
+	  multimedia processors.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called omap-rng.
+
+ 	  If unsure, say Y.
+
+config HW_RANDOM_OMAP3_ROM
+	tristate "OMAP3 ROM Random Number Generator support"
+	depends on ARCH_OMAP3
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on OMAP34xx processors.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called omap3-rom-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_OCTEON
+	tristate "Octeon Random Number Generator support"
+	depends on CAVIUM_OCTEON_SOC
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Octeon processors.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called octeon-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_PASEMI
+	tristate "PA Semi HW Random Number Generator support"
+	depends on PPC_PASEMI
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on PA Semi PWRficient SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called pasemi-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_VIRTIO
+	tristate "VirtIO Random Number Generator support"
+	depends on VIRTIO
+	---help---
+	  This driver provides kernel-side support for the virtual Random Number
+	  Generator hardware.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called virtio-rng.  If unsure, say N.
+
+config HW_RANDOM_TX4939
+	tristate "TX4939 Random Number Generator support"
+	depends on SOC_TX4939
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on TX4939 SoC.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called tx4939-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_MXC_RNGA
+	tristate "Freescale i.MX RNGA Random Number Generator"
+	depends on ARCH_HAS_RNGA
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Freescale i.MX processors.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mxc-rnga.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_NOMADIK
+	tristate "ST-Ericsson Nomadik Random Number Generator support"
+	depends on ARCH_NOMADIK
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on ST-Ericsson SoCs (8815 and 8500).
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called nomadik-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_PPC4XX
+	tristate "PowerPC 4xx generic true random number generator support"
+	depends on PPC && 4xx
+	default HW_RANDOM
+	---help---
+	 This driver provides the kernel-side support for the TRNG hardware
+	 found in the security function of some PowerPC 4xx SoCs.
+
+	 To compile this driver as a module, choose M here: the
+	 module will be called ppc4xx-rng.
+
+	 If unsure, say N.
+
+config HW_RANDOM_PSERIES
+	tristate "pSeries HW Random Number Generator support"
+	depends on PPC64 && IBMVIO
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on POWER7+ machines and above
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called pseries-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_POWERNV
+	tristate "PowerNV Random Number Generator support"
+	depends on PPC_POWERNV
+	default HW_RANDOM
+	---help---
+	  This is the driver for Random Number Generator hardware found
+	  in POWER7+ and above machines for PowerNV platform.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called powernv-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_EXYNOS
+	tristate "EXYNOS HW random number generator support"
+	depends on ARCH_EXYNOS
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on EXYNOS SOCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called exynos-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_EXYNOS_SWD
+	tristate "EXYNOS SWD HW random number generator support"
+	depends on ARCH_EXYNOS
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for TRNG hardware
+	  found in secure world by using smc call
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called exynos-rng.
+
+	  If unsure, say Y.
+
+config EXYRNG_FIPS_COMPLIANCE
+	bool "Compliant with FIPS 140-2"
+	depends on HW_RANDOM_EXYNOS_SWD
+
+choice
+	prompt "Fail Policy"
+	depends on EXYRNG_FIPS_COMPLIANCE
+	default EXYRNG_FAIL_POLICY_DISABLE
+
+config EXYRNG_FAIL_POLICY_DISABLE
+	bool "Disable RNG if the tests fail"
+	depends on EXYRNG_FIPS_COMPLIANCE
+
+config EXYRNG_FAIL_POLICY_RESET
+	bool "Reset if the tests fail"
+	depends on EXYRNG_FIPS_COMPLIANCE
+
+endchoice
+
+config EXYRNG_USE_CRYPTOMANAGER
+	tristate "Use CryptoManager"
+	depends on HW_RANDOM_EXYNOS_SWD
+	default n
+
+config HW_RANDOM_TPM
+	tristate "TPM HW Random Number Generator support"
+	depends on TCG_TPM
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator in the Trusted Platform Module
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called tpm-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_MSM
+	tristate "Qualcomm SoCs Random Number Generator support"
+	depends on HW_RANDOM && ARCH_QCOM
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on Qualcomm SoCs.
+
+	  To compile this driver as a module, choose M here. the
+	  module will be called msm-rng.
+
+	  If unsure, say Y.
+
+config HW_RANDOM_XGENE
+	tristate "APM X-Gene True Random Number Generator (TRNG) support"
+	depends on HW_RANDOM && ARCH_XGENE
+	default HW_RANDOM
+	---help---
+	  This driver provides kernel-side support for the Random Number
+	  Generator hardware found on APM X-Gene SoC.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called xgene_rng.
+
+	  If unsure, say Y.
+
+endif # HW_RANDOM
+
+config UML_RANDOM
+	depends on UML
+	tristate "Hardware random number generator"
+	help
+	  This option enables UML's "hardware" random number generator.  It
+	  attaches itself to the host's /dev/random, supplying as much entropy
+	  as the host has, rather than the small amount the UML gets from its
+	  own drivers.  It registers itself as a standard hardware random number
+	  generator, major 10, minor 183, and the canonical device name is
+	  /dev/hwrng.
+	  The way to make use of this is to install the rng-tools package
+	  (check your distro, or download from
+	  http://sourceforge.net/projects/gkernel/).  rngd periodically reads
+	  /dev/hwrng and injects the entropy into /dev/random.
+

drivers/char/hw_random/Makefile

@@ -0,0 +1,33 @@
+#
+# Makefile for HW Random Number Generator (RNG) device drivers.
+#
+
+obj-$(CONFIG_HW_RANDOM) += rng-core.o
+rng-core-y := core.o
+obj-$(CONFIG_HW_RANDOM_EXYNOS_SWD) += exyswd-rng.o
+obj-$(CONFIG_HW_RANDOM_TIMERIOMEM) += timeriomem-rng.o
+obj-$(CONFIG_HW_RANDOM_INTEL) += intel-rng.o
+obj-$(CONFIG_HW_RANDOM_AMD) += amd-rng.o
+obj-$(CONFIG_HW_RANDOM_ATMEL) += atmel-rng.o
+obj-$(CONFIG_HW_RANDOM_BCM63XX)	+= bcm63xx-rng.o
+obj-$(CONFIG_HW_RANDOM_GEODE) += geode-rng.o
+obj-$(CONFIG_HW_RANDOM_N2RNG) += n2-rng.o
+n2-rng-y := n2-drv.o n2-asm.o
+obj-$(CONFIG_HW_RANDOM_VIA) += via-rng.o
+obj-$(CONFIG_HW_RANDOM_IXP4XX) += ixp4xx-rng.o
+obj-$(CONFIG_HW_RANDOM_OMAP) += omap-rng.o
+obj-$(CONFIG_HW_RANDOM_OMAP3_ROM) += omap3-rom-rng.o
+obj-$(CONFIG_HW_RANDOM_PASEMI) += pasemi-rng.o
+obj-$(CONFIG_HW_RANDOM_VIRTIO) += virtio-rng.o
+obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o
+obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o
+obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o
+obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
+obj-$(CONFIG_HW_RANDOM_PPC4XX) += ppc4xx-rng.o
+obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o
+obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o
+obj-$(CONFIG_HW_RANDOM_EXYNOS)	+= exynos-rng.o
+obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o
+obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o
+obj-$(CONFIG_HW_RANDOM_MSM) += msm-rng.o
+obj-$(CONFIG_HW_RANDOM_XGENE) += xgene-rng.o

drivers/char/hw_random/amd-rng.c

@@ -0,0 +1,169 @@
+/*
+ * RNG driver for AMD RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+
+#define PFX	KBUILD_MODNAME ": "
+
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id pci_tbl[] = {
+	{ PCI_VDEVICE(AMD, 0x7443), 0, },
+	{ PCI_VDEVICE(AMD, 0x746b), 0, },
+	{ 0, },	/* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, pci_tbl);
+
+static struct pci_dev *amd_pdev;
+
+
+static int amd_rng_data_present(struct hwrng *rng, int wait)
+{
+	u32 pmbase = (u32)rng->priv;
+	int data, i;
+
+	for (i = 0; i < 20; i++) {
+		data = !!(inl(pmbase + 0xF4) & 1);
+		if (data || !wait)
+			break;
+		udelay(10);
+	}
+	return data;
+}
+
+static int amd_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	u32 pmbase = (u32)rng->priv;
+
+	*data = inl(pmbase + 0xF0);
+
+	return 4;
+}
+
+static int amd_rng_init(struct hwrng *rng)
+{
+	u8 rnen;
+
+	pci_read_config_byte(amd_pdev, 0x40, &rnen);
+	rnen |= (1 << 7);	/* RNG on */
+	pci_write_config_byte(amd_pdev, 0x40, rnen);
+
+	pci_read_config_byte(amd_pdev, 0x41, &rnen);
+	rnen |= (1 << 7);	/* PMIO enable */
+	pci_write_config_byte(amd_pdev, 0x41, rnen);
+
+	return 0;
+}
+
+static void amd_rng_cleanup(struct hwrng *rng)
+{
+	u8 rnen;
+
+	pci_read_config_byte(amd_pdev, 0x40, &rnen);
+	rnen &= ~(1 << 7);	/* RNG off */
+	pci_write_config_byte(amd_pdev, 0x40, rnen);
+}
+
+
+static struct hwrng amd_rng = {
+	.name		= "amd",
+	.init		= amd_rng_init,
+	.cleanup	= amd_rng_cleanup,
+	.data_present	= amd_rng_data_present,
+	.data_read	= amd_rng_data_read,
+};
+
+
+static int __init mod_init(void)
+{
+	int err = -ENODEV;
+	struct pci_dev *pdev = NULL;
+	const struct pci_device_id *ent;
+	u32 pmbase;
+
+	for_each_pci_dev(pdev) {
+		ent = pci_match_id(pci_tbl, pdev);
+		if (ent)
+			goto found;
+	}
+	/* Device not found. */
+	goto out;
+
+found:
+	err = pci_read_config_dword(pdev, 0x58, &pmbase);
+	if (err)
+		goto out;
+	err = -EIO;
+	pmbase &= 0x0000FF00;
+	if (pmbase == 0)
+		goto out;
+	if (!request_region(pmbase + 0xF0, 8, "AMD HWRNG")) {
+		dev_err(&pdev->dev, "AMD HWRNG region 0x%x already in use!\n",
+			pmbase + 0xF0);
+		err = -EBUSY;
+		goto out;
+	}
+	amd_rng.priv = (unsigned long)pmbase;
+	amd_pdev = pdev;
+
+	pr_info("AMD768 RNG detected\n");
+	err = hwrng_register(&amd_rng);
+	if (err) {
+		pr_err(PFX "RNG registering failed (%d)\n",
+		       err);
+		release_region(pmbase + 0xF0, 8);
+		goto out;
+	}
+out:
+	return err;
+}
+
+static void __exit mod_exit(void)
+{
+	u32 pmbase = (unsigned long)amd_rng.priv;
+	release_region(pmbase + 0xF0, 8);
+	hwrng_unregister(&amd_rng);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_AUTHOR("The Linux Kernel team");
+MODULE_DESCRIPTION("H/W RNG driver for AMD chipsets");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/atmel-rng.c

@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2011 Peter Korsgaard <jacmet@sunsite.dk>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/hw_random.h>
+#include <linux/platform_device.h>
+
+#define TRNG_CR		0x00
+#define TRNG_ISR	0x1c
+#define TRNG_ODATA	0x50
+
+#define TRNG_KEY	0x524e4700 /* RNG */
+
+struct atmel_trng {
+	struct clk *clk;
+	void __iomem *base;
+	struct hwrng rng;
+};
+
+static int atmel_trng_read(struct hwrng *rng, void *buf, size_t max,
+			   bool wait)
+{
+	struct atmel_trng *trng = container_of(rng, struct atmel_trng, rng);
+	u32 *data = buf;
+
+	/* data ready? */
+	if (readl(trng->base + TRNG_ISR) & 1) {
+		*data = readl(trng->base + TRNG_ODATA);
+		/*
+		  ensure data ready is only set again AFTER the next data
+		  word is ready in case it got set between checking ISR
+		  and reading ODATA, so we don't risk re-reading the
+		  same word
+		*/
+		readl(trng->base + TRNG_ISR);
+		return 4;
+	} else
+		return 0;
+}
+
+static int atmel_trng_probe(struct platform_device *pdev)
+{
+	struct atmel_trng *trng;
+	struct resource *res;
+	int ret;
+
+	trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
+	if (!trng)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	trng->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(trng->base))
+		return PTR_ERR(trng->base);
+
+	trng->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(trng->clk))
+		return PTR_ERR(trng->clk);
+
+	ret = clk_enable(trng->clk);
+	if (ret)
+		return ret;
+
+	writel(TRNG_KEY | 1, trng->base + TRNG_CR);
+	trng->rng.name = pdev->name;
+	trng->rng.read = atmel_trng_read;
+
+	ret = hwrng_register(&trng->rng);
+	if (ret)
+		goto err_register;
+
+	platform_set_drvdata(pdev, trng);
+
+	return 0;
+
+err_register:
+	clk_disable(trng->clk);
+	return ret;
+}
+
+static int atmel_trng_remove(struct platform_device *pdev)
+{
+	struct atmel_trng *trng = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&trng->rng);
+
+	writel(TRNG_KEY, trng->base + TRNG_CR);
+	clk_disable(trng->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int atmel_trng_suspend(struct device *dev)
+{
+	struct atmel_trng *trng = dev_get_drvdata(dev);
+
+	clk_disable(trng->clk);
+
+	return 0;
+}
+
+static int atmel_trng_resume(struct device *dev)
+{
+	struct atmel_trng *trng = dev_get_drvdata(dev);
+
+	return clk_enable(trng->clk);
+}
+
+static const struct dev_pm_ops atmel_trng_pm_ops = {
+	.suspend	= atmel_trng_suspend,
+	.resume		= atmel_trng_resume,
+};
+#endif /* CONFIG_PM */
+
+static struct platform_driver atmel_trng_driver = {
+	.probe		= atmel_trng_probe,
+	.remove		= atmel_trng_remove,
+	.driver		= {
+		.name	= "atmel-trng",
+		.owner	= THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm	= &atmel_trng_pm_ops,
+#endif /* CONFIG_PM */
+	},
+};
+
+module_platform_driver(atmel_trng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
+MODULE_DESCRIPTION("Atmel true random number generator driver");

drivers/char/hw_random/bcm2835-rng.c

@@ -0,0 +1,112 @@
+/**
+ * Copyright (c) 2010-2012 Broadcom. All rights reserved.
+ * Copyright (c) 2013 Lubomir Rintel
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License ("GPL")
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+
+#define RNG_CTRL	0x0
+#define RNG_STATUS	0x4
+#define RNG_DATA	0x8
+
+/* enable rng */
+#define RNG_RBGEN	0x1
+
+/* the initial numbers generated are "less random" so will be discarded */
+#define RNG_WARMUP_COUNT 0x40000
+
+static int bcm2835_rng_read(struct hwrng *rng, void *buf, size_t max,
+			       bool wait)
+{
+	void __iomem *rng_base = (void __iomem *)rng->priv;
+
+	while ((__raw_readl(rng_base + RNG_STATUS) >> 24) == 0) {
+		if (!wait)
+			return 0;
+		cpu_relax();
+	}
+
+	*(u32 *)buf = __raw_readl(rng_base + RNG_DATA);
+	return sizeof(u32);
+}
+
+static struct hwrng bcm2835_rng_ops = {
+	.name	= "bcm2835",
+	.read	= bcm2835_rng_read,
+};
+
+static int bcm2835_rng_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	void __iomem *rng_base;
+	int err;
+
+	/* map peripheral */
+	rng_base = of_iomap(np, 0);
+	if (!rng_base) {
+		dev_err(dev, "failed to remap rng regs");
+		return -ENODEV;
+	}
+	bcm2835_rng_ops.priv = (unsigned long)rng_base;
+
+	/* set warm-up count & enable */
+	__raw_writel(RNG_WARMUP_COUNT, rng_base + RNG_STATUS);
+	__raw_writel(RNG_RBGEN, rng_base + RNG_CTRL);
+
+	/* register driver */
+	err = hwrng_register(&bcm2835_rng_ops);
+	if (err) {
+		dev_err(dev, "hwrng registration failed\n");
+		iounmap(rng_base);
+	} else
+		dev_info(dev, "hwrng registered\n");
+
+	return err;
+}
+
+static int bcm2835_rng_remove(struct platform_device *pdev)
+{
+	void __iomem *rng_base = (void __iomem *)bcm2835_rng_ops.priv;
+
+	/* disable rng hardware */
+	__raw_writel(0, rng_base + RNG_CTRL);
+
+	/* unregister driver */
+	hwrng_unregister(&bcm2835_rng_ops);
+	iounmap(rng_base);
+
+	return 0;
+}
+
+static const struct of_device_id bcm2835_rng_of_match[] = {
+	{ .compatible = "brcm,bcm2835-rng", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, bcm2835_rng_of_match);
+
+static struct platform_driver bcm2835_rng_driver = {
+	.driver = {
+		.name = "bcm2835-rng",
+		.owner = THIS_MODULE,
+		.of_match_table = bcm2835_rng_of_match,
+	},
+	.probe		= bcm2835_rng_probe,
+	.remove		= bcm2835_rng_remove,
+};
+module_platform_driver(bcm2835_rng_driver);
+
+MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
+MODULE_DESCRIPTION("BCM2835 Random Number Generator (RNG) driver");
+MODULE_LICENSE("GPL v2");

drivers/char/hw_random/bcm63xx-rng.c

@@ -0,0 +1,173 @@
+/*
+ * Broadcom BCM63xx Random Number Generator support
+ *
+ * Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
+ * Copyright (C) 2009, Broadcom Corporation
+ *
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+
+#include <bcm63xx_io.h>
+#include <bcm63xx_regs.h>
+
+struct bcm63xx_rng_priv {
+	struct clk *clk;
+	void __iomem *regs;
+};
+
+#define to_rng_priv(rng)	((struct bcm63xx_rng_priv *)rng->priv)
+
+static int bcm63xx_rng_init(struct hwrng *rng)
+{
+	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+	u32 val;
+
+	val = bcm_readl(priv->regs + RNG_CTRL);
+	val |= RNG_EN;
+	bcm_writel(val, priv->regs + RNG_CTRL);
+
+	return 0;
+}
+
+static void bcm63xx_rng_cleanup(struct hwrng *rng)
+{
+	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+	u32 val;
+
+	val = bcm_readl(priv->regs + RNG_CTRL);
+	val &= ~RNG_EN;
+	bcm_writel(val, priv->regs + RNG_CTRL);
+}
+
+static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
+{
+	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+	return bcm_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
+}
+
+static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+	*data = bcm_readl(priv->regs + RNG_DATA);
+
+	return 4;
+}
+
+static int bcm63xx_rng_probe(struct platform_device *pdev)
+{
+	struct resource *r;
+	struct clk *clk;
+	int ret;
+	struct bcm63xx_rng_priv *priv;
+	struct hwrng *rng;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		dev_err(&pdev->dev, "no iomem resource\n");
+		ret = -ENXIO;
+		goto out;
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		dev_err(&pdev->dev, "no memory for private structure\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	rng = kzalloc(sizeof(*rng), GFP_KERNEL);
+	if (!rng) {
+		dev_err(&pdev->dev, "no memory for rng structure\n");
+		ret = -ENOMEM;
+		goto out_free_priv;
+	}
+
+	platform_set_drvdata(pdev, rng);
+	rng->priv = (unsigned long)priv;
+	rng->name = pdev->name;
+	rng->init = bcm63xx_rng_init;
+	rng->cleanup = bcm63xx_rng_cleanup;
+	rng->data_present = bcm63xx_rng_data_present;
+	rng->data_read = bcm63xx_rng_data_read;
+
+	clk = clk_get(&pdev->dev, "ipsec");
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "no clock for device\n");
+		ret = PTR_ERR(clk);
+		goto out_free_rng;
+	}
+
+	priv->clk = clk;
+
+	if (!devm_request_mem_region(&pdev->dev, r->start,
+					resource_size(r), pdev->name)) {
+		dev_err(&pdev->dev, "request mem failed");
+		ret = -ENOMEM;
+		goto out_free_rng;
+	}
+
+	priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
+					resource_size(r));
+	if (!priv->regs) {
+		dev_err(&pdev->dev, "ioremap failed");
+		ret = -ENOMEM;
+		goto out_free_rng;
+	}
+
+	clk_enable(clk);
+
+	ret = hwrng_register(rng);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register rng device\n");
+		goto out_clk_disable;
+	}
+
+	dev_info(&pdev->dev, "registered RNG driver\n");
+
+	return 0;
+
+out_clk_disable:
+	clk_disable(clk);
+out_free_rng:
+	kfree(rng);
+out_free_priv:
+	kfree(priv);
+out:
+	return ret;
+}
+
+static int bcm63xx_rng_remove(struct platform_device *pdev)
+{
+	struct hwrng *rng = platform_get_drvdata(pdev);
+	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
+
+	hwrng_unregister(rng);
+	clk_disable(priv->clk);
+	kfree(priv);
+	kfree(rng);
+
+	return 0;
+}
+
+static struct platform_driver bcm63xx_rng_driver = {
+	.probe		= bcm63xx_rng_probe,
+	.remove		= bcm63xx_rng_remove,
+	.driver		= {
+		.name	= "bcm63xx-rng",
+		.owner	= THIS_MODULE,
+	},
+};
+
+module_platform_driver(bcm63xx_rng_driver);
+
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/core.c

@@ -0,0 +1,501 @@
+/*
+        Added support for the AMD Geode LX RNG
+	(c) Copyright 2004-2005 Advanced Micro Devices, Inc.
+
+	derived from
+
+ 	Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+	(c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+
+ 	derived from
+
+        Hardware driver for the AMD 768 Random Number Generator (RNG)
+        (c) Copyright 2001 Red Hat Inc <alan@redhat.com>
+
+ 	derived from
+
+	Hardware driver for Intel i810 Random Number Generator (RNG)
+	Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+	Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+
+	Added generic RNG API
+	Copyright 2006 Michael Buesch <m@bues.ch>
+	Copyright 2005 (c) MontaVista Software, Inc.
+
+	Please read Documentation/hw_random.txt for details on use.
+
+	----------------------------------------------------------
+	This software may be used and distributed according to the terms
+        of the GNU General Public License, incorporated herein by reference.
+
+ */
+
+
+#include <linux/device.h>
+#include <linux/hw_random.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/miscdevice.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/freezer.h>
+#include <asm/uaccess.h>
+
+
+#define RNG_MODULE_NAME		"hw_random"
+#define PFX			RNG_MODULE_NAME ": "
+#define RNG_MISCDEV_MINOR	183 /* official */
+
+
+static struct hwrng *current_rng;
+static struct task_struct *hwrng_fill;
+static LIST_HEAD(rng_list);
+/* Protects rng_list and current_rng */
+static DEFINE_MUTEX(rng_mutex);
+/* Protects rng read functions, data_avail, rng_buffer and rng_fillbuf */
+static DEFINE_MUTEX(reading_mutex);
+static int data_avail;
+static u8 *rng_buffer, *rng_fillbuf;
+static unsigned short current_quality;
+static unsigned short default_quality; /* = 0; default to "off" */
+
+module_param(current_quality, ushort, 0644);
+MODULE_PARM_DESC(current_quality,
+		 "current hwrng entropy estimation per mill");
+module_param(default_quality, ushort, 0644);
+MODULE_PARM_DESC(default_quality,
+		 "default entropy content of hwrng per mill");
+
+static void start_khwrngd(void);
+
+static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
+			       int wait);
+
+static size_t rng_buffer_size(void)
+{
+	return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES;
+}
+
+static void add_early_randomness(struct hwrng *rng)
+{
+	unsigned char bytes[16];
+	int bytes_read;
+
+	mutex_lock(&reading_mutex);
+	bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1);
+	mutex_unlock(&reading_mutex);
+	if (bytes_read > 0)
+		add_device_randomness(bytes, bytes_read);
+}
+
+static inline int hwrng_init(struct hwrng *rng)
+{
+	if (rng->init) {
+		int ret;
+
+		ret =  rng->init(rng);
+		if (ret)
+			return ret;
+	}
+	add_early_randomness(rng);
+
+	current_quality = rng->quality ? : default_quality;
+	current_quality &= 1023;
+
+	if (current_quality == 0 && hwrng_fill)
+		kthread_stop(hwrng_fill);
+	if (current_quality > 0 && !hwrng_fill)
+		start_khwrngd();
+
+	return 0;
+}
+
+static inline void hwrng_cleanup(struct hwrng *rng)
+{
+	if (rng && rng->cleanup)
+		rng->cleanup(rng);
+}
+
+static int rng_dev_open(struct inode *inode, struct file *filp)
+{
+	/* enforce read-only access to this chrdev */
+	if ((filp->f_mode & FMODE_READ) == 0)
+		return -EINVAL;
+	if (filp->f_mode & FMODE_WRITE)
+		return -EINVAL;
+	return 0;
+}
+
+static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
+			int wait) {
+	int present;
+
+	BUG_ON(!mutex_is_locked(&reading_mutex));
+	if (rng->read)
+		return rng->read(rng, (void *)buffer, size, wait);
+
+	if (rng->data_present)
+		present = rng->data_present(rng, wait);
+	else
+		present = 1;
+
+	if (present)
+		return rng->data_read(rng, (u32 *)buffer);
+
+	return 0;
+}
+
+static ssize_t rng_dev_read(struct file *filp, char __user *buf,
+			    size_t size, loff_t *offp)
+{
+	ssize_t ret = 0;
+	int err = 0;
+	int bytes_read, len;
+
+	while (size) {
+		if (mutex_lock_interruptible(&rng_mutex)) {
+			err = -ERESTARTSYS;
+			goto out;
+		}
+
+		if (!current_rng) {
+			err = -ENODEV;
+			goto out_unlock;
+		}
+
+		mutex_lock(&reading_mutex);
+		if (!data_avail) {
+			bytes_read = rng_get_data(current_rng, rng_buffer,
+				rng_buffer_size(),
+				!(filp->f_flags & O_NONBLOCK));
+			if (bytes_read < 0) {
+				err = bytes_read;
+				goto out_unlock_reading;
+			}
+			data_avail = bytes_read;
+		}
+
+		if (!data_avail) {
+			if (filp->f_flags & O_NONBLOCK) {
+				err = -EAGAIN;
+				goto out_unlock_reading;
+			}
+		} else {
+			len = data_avail;
+			if (len > size)
+				len = size;
+
+			data_avail -= len;
+
+			if (copy_to_user(buf + ret, rng_buffer + data_avail,
+								len)) {
+				err = -EFAULT;
+				goto out_unlock_reading;
+			}
+
+			size -= len;
+			ret += len;
+		}
+
+		mutex_unlock(&rng_mutex);
+		mutex_unlock(&reading_mutex);
+
+		if (need_resched())
+			schedule_timeout_interruptible(1);
+
+		if (signal_pending(current)) {
+			err = -ERESTARTSYS;
+			goto out;
+		}
+	}
+out:
+	return ret ? : err;
+out_unlock:
+	mutex_unlock(&rng_mutex);
+	goto out;
+out_unlock_reading:
+	mutex_unlock(&reading_mutex);
+	goto out_unlock;
+}
+
+
+static const struct file_operations rng_chrdev_ops = {
+	.owner		= THIS_MODULE,
+	.open		= rng_dev_open,
+	.read		= rng_dev_read,
+	.llseek		= noop_llseek,
+};
+
+static struct miscdevice rng_miscdev = {
+	.minor		= RNG_MISCDEV_MINOR,
+	.name		= RNG_MODULE_NAME,
+	.nodename	= "hwrng",
+	.fops		= &rng_chrdev_ops,
+};
+
+
+static ssize_t hwrng_attr_current_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t len)
+{
+	int err;
+	struct hwrng *rng;
+
+	err = mutex_lock_interruptible(&rng_mutex);
+	if (err)
+		return -ERESTARTSYS;
+	err = -ENODEV;
+	list_for_each_entry(rng, &rng_list, list) {
+		if (strcmp(rng->name, buf) == 0) {
+			if (rng == current_rng) {
+				err = 0;
+				break;
+			}
+			err = hwrng_init(rng);
+			if (err)
+				break;
+			hwrng_cleanup(current_rng);
+			current_rng = rng;
+			err = 0;
+			break;
+		}
+	}
+	mutex_unlock(&rng_mutex);
+
+	return err ? : len;
+}
+
+static ssize_t hwrng_attr_current_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	int err;
+	ssize_t ret;
+	const char *name = "none";
+
+	err = mutex_lock_interruptible(&rng_mutex);
+	if (err)
+		return -ERESTARTSYS;
+	if (current_rng)
+		name = current_rng->name;
+	ret = snprintf(buf, PAGE_SIZE, "%s\n", name);
+	mutex_unlock(&rng_mutex);
+
+	return ret;
+}
+
+static ssize_t hwrng_attr_available_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	int err;
+	ssize_t ret = 0;
+	struct hwrng *rng;
+
+	err = mutex_lock_interruptible(&rng_mutex);
+	if (err)
+		return -ERESTARTSYS;
+	buf[0] = '\0';
+	list_for_each_entry(rng, &rng_list, list) {
+		strncat(buf, rng->name, PAGE_SIZE - ret - 1);
+		ret += strlen(rng->name);
+		strncat(buf, " ", PAGE_SIZE - ret - 1);
+		ret++;
+	}
+	strncat(buf, "\n", PAGE_SIZE - ret - 1);
+	ret++;
+	mutex_unlock(&rng_mutex);
+
+	return ret;
+}
+
+static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR,
+		   hwrng_attr_current_show,
+		   hwrng_attr_current_store);
+static DEVICE_ATTR(rng_available, S_IRUGO,
+		   hwrng_attr_available_show,
+		   NULL);
+
+
+static void unregister_miscdev(void)
+{
+	device_remove_file(rng_miscdev.this_device, &dev_attr_rng_available);
+	device_remove_file(rng_miscdev.this_device, &dev_attr_rng_current);
+	misc_deregister(&rng_miscdev);
+}
+
+static int register_miscdev(void)
+{
+	int err;
+
+	err = misc_register(&rng_miscdev);
+	if (err)
+		goto out;
+	err = device_create_file(rng_miscdev.this_device,
+				 &dev_attr_rng_current);
+	if (err)
+		goto err_misc_dereg;
+	err = device_create_file(rng_miscdev.this_device,
+				 &dev_attr_rng_available);
+	if (err)
+		goto err_remove_current;
+out:
+	return err;
+
+err_remove_current:
+	device_remove_file(rng_miscdev.this_device, &dev_attr_rng_current);
+err_misc_dereg:
+	misc_deregister(&rng_miscdev);
+	goto out;
+}
+
+static int hwrng_fillfn(void *unused)
+{
+	long rc;
+
+	set_freezable();
+
+	while (!kthread_should_stop()) {
+		if (!current_rng)
+			break;
+		mutex_lock(&reading_mutex);
+		rc = rng_get_data(current_rng, rng_fillbuf,
+				  rng_buffer_size(), 1);
+		mutex_unlock(&reading_mutex);
+		if (rc <= 0) {
+			pr_warn("hwrng: no data available\n");
+			msleep_interruptible(10000);
+			continue;
+		}
+		/* Outside lock, sure, but y'know: randomness. */
+		add_hwgenerator_randomness((void *)rng_fillbuf, rc,
+					   rc * current_quality * 8 >> 10);
+	}
+	hwrng_fill = NULL;
+	return 0;
+}
+
+static void start_khwrngd(void)
+{
+	hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
+	if (hwrng_fill == ERR_PTR(-ENOMEM)) {
+		pr_err("hwrng_fill thread creation failed");
+		hwrng_fill = NULL;
+	}
+}
+
+int hwrng_register(struct hwrng *rng)
+{
+	int err = -EINVAL;
+	struct hwrng *old_rng, *tmp;
+
+	if (rng->name == NULL ||
+	    (rng->data_read == NULL && rng->read == NULL))
+		goto out;
+
+	mutex_lock(&rng_mutex);
+
+	/* kmalloc makes this safe for virt_to_page() in virtio_rng.c */
+	err = -ENOMEM;
+	if (!rng_buffer) {
+		rng_buffer = kmalloc(rng_buffer_size(), GFP_KERNEL);
+		if (!rng_buffer)
+			goto out_unlock;
+	}
+	if (!rng_fillbuf) {
+		rng_fillbuf = kmalloc(rng_buffer_size(), GFP_KERNEL);
+		if (!rng_fillbuf) {
+			kfree(rng_buffer);
+			goto out_unlock;
+		}
+	}
+
+	/* Must not register two RNGs with the same name. */
+	err = -EEXIST;
+	list_for_each_entry(tmp, &rng_list, list) {
+		if (strcmp(tmp->name, rng->name) == 0)
+			goto out_unlock;
+	}
+
+	old_rng = current_rng;
+	if (!old_rng) {
+		err = hwrng_init(rng);
+		if (err)
+			goto out_unlock;
+		current_rng = rng;
+	}
+	err = 0;
+	if (!old_rng) {
+		err = register_miscdev();
+		if (err) {
+			hwrng_cleanup(rng);
+			current_rng = NULL;
+			goto out_unlock;
+		}
+	}
+	INIT_LIST_HEAD(&rng->list);
+	list_add_tail(&rng->list, &rng_list);
+
+	if (old_rng && !rng->init) {
+		/*
+		 * Use a new device's input to add some randomness to
+		 * the system.  If this rng device isn't going to be
+		 * used right away, its init function hasn't been
+		 * called yet; so only use the randomness from devices
+		 * that don't need an init callback.
+		 */
+		add_early_randomness(rng);
+	}
+
+out_unlock:
+	mutex_unlock(&rng_mutex);
+out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(hwrng_register);
+
+void hwrng_unregister(struct hwrng *rng)
+{
+	int err;
+
+	mutex_lock(&rng_mutex);
+
+	list_del(&rng->list);
+	if (current_rng == rng) {
+		hwrng_cleanup(rng);
+		if (list_empty(&rng_list)) {
+			current_rng = NULL;
+		} else {
+			current_rng = list_entry(rng_list.prev, struct hwrng, list);
+			err = hwrng_init(current_rng);
+			if (err)
+				current_rng = NULL;
+		}
+	}
+	if (list_empty(&rng_list)) {
+		unregister_miscdev();
+		if (hwrng_fill)
+			kthread_stop(hwrng_fill);
+	}
+
+	mutex_unlock(&rng_mutex);
+}
+EXPORT_SYMBOL_GPL(hwrng_unregister);
+
+static void __exit hwrng_exit(void)
+{
+	mutex_lock(&rng_mutex);
+	BUG_ON(current_rng);
+	kfree(rng_buffer);
+	kfree(rng_fillbuf);
+	mutex_unlock(&rng_mutex);
+}
+
+module_exit(hwrng_exit);
+
+MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/exynos-rng.c

@@ -0,0 +1,183 @@
+/*
+ * exynos-rng.c - Random Number Generator driver for the exynos
+ *
+ * Copyright (C) 2012 Samsung Electronics
+ * Jonghwa Lee <jonghwa3.lee@smasung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/hw_random.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/err.h>
+
+#define EXYNOS_PRNG_STATUS_OFFSET	0x10
+#define EXYNOS_PRNG_SEED_OFFSET		0x140
+#define EXYNOS_PRNG_OUT1_OFFSET		0x160
+#define SEED_SETTING_DONE		BIT(1)
+#define PRNG_START			0x18
+#define PRNG_DONE			BIT(5)
+#define EXYNOS_AUTOSUSPEND_DELAY	100
+
+struct exynos_rng {
+	struct device *dev;
+	struct hwrng rng;
+	void __iomem *mem;
+	struct clk *clk;
+};
+
+static u32 exynos_rng_readl(struct exynos_rng *rng, u32 offset)
+{
+	return	__raw_readl(rng->mem + offset);
+}
+
+static void exynos_rng_writel(struct exynos_rng *rng, u32 val, u32 offset)
+{
+	__raw_writel(val, rng->mem + offset);
+}
+
+static int exynos_init(struct hwrng *rng)
+{
+	struct exynos_rng *exynos_rng = container_of(rng,
+						struct exynos_rng, rng);
+	int i;
+	int ret = 0;
+
+	pm_runtime_get_sync(exynos_rng->dev);
+
+	for (i = 0 ; i < 5 ; i++)
+		exynos_rng_writel(exynos_rng, jiffies,
+				EXYNOS_PRNG_SEED_OFFSET + 4*i);
+
+	if (!(exynos_rng_readl(exynos_rng, EXYNOS_PRNG_STATUS_OFFSET)
+						 & SEED_SETTING_DONE))
+		ret = -EIO;
+
+	pm_runtime_put_noidle(exynos_rng->dev);
+
+	return ret;
+}
+
+static int exynos_read(struct hwrng *rng, void *buf,
+					size_t max, bool wait)
+{
+	struct exynos_rng *exynos_rng = container_of(rng,
+						struct exynos_rng, rng);
+	u32 *data = buf;
+
+	pm_runtime_get_sync(exynos_rng->dev);
+
+	exynos_rng_writel(exynos_rng, PRNG_START, 0);
+
+	while (!(exynos_rng_readl(exynos_rng,
+			EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE))
+		cpu_relax();
+
+	exynos_rng_writel(exynos_rng, PRNG_DONE, EXYNOS_PRNG_STATUS_OFFSET);
+
+	*data = exynos_rng_readl(exynos_rng, EXYNOS_PRNG_OUT1_OFFSET);
+
+	pm_runtime_mark_last_busy(exynos_rng->dev);
+	pm_runtime_autosuspend(exynos_rng->dev);
+
+	return 4;
+}
+
+static int exynos_rng_probe(struct platform_device *pdev)
+{
+	struct exynos_rng *exynos_rng;
+	struct resource *res;
+
+	exynos_rng = devm_kzalloc(&pdev->dev, sizeof(struct exynos_rng),
+					GFP_KERNEL);
+	if (!exynos_rng)
+		return -ENOMEM;
+
+	exynos_rng->dev = &pdev->dev;
+	exynos_rng->rng.name = "exynos";
+	exynos_rng->rng.init =	exynos_init;
+	exynos_rng->rng.read = exynos_read;
+	exynos_rng->clk = devm_clk_get(&pdev->dev, "secss");
+	if (IS_ERR(exynos_rng->clk)) {
+		dev_err(&pdev->dev, "Couldn't get clock.\n");
+		return -ENOENT;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	exynos_rng->mem = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(exynos_rng->mem))
+		return PTR_ERR(exynos_rng->mem);
+
+	platform_set_drvdata(pdev, exynos_rng);
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, EXYNOS_AUTOSUSPEND_DELAY);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return hwrng_register(&exynos_rng->rng);
+}
+
+static int exynos_rng_remove(struct platform_device *pdev)
+{
+	struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&exynos_rng->rng);
+
+	return 0;
+}
+
+#if defined(CONFIG_PM_SLEEP) || defined(CONFIG_PM_RUNTIME)
+static int exynos_rng_runtime_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(exynos_rng->clk);
+
+	return 0;
+}
+
+static int exynos_rng_runtime_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
+
+	return clk_prepare_enable(exynos_rng->clk);
+}
+#endif
+
+static UNIVERSAL_DEV_PM_OPS(exynos_rng_pm_ops, exynos_rng_runtime_suspend,
+					exynos_rng_runtime_resume, NULL);
+
+static struct platform_driver exynos_rng_driver = {
+	.driver		= {
+		.name	= "exynos-rng",
+		.owner	= THIS_MODULE,
+		.pm	= &exynos_rng_pm_ops,
+	},
+	.probe		= exynos_rng_probe,
+	.remove		= exynos_rng_remove,
+};
+
+module_platform_driver(exynos_rng_driver);
+
+MODULE_DESCRIPTION("EXYNOS 4 H/W Random Number Generator driver");
+MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/exyswd-rng.c

@@ -0,0 +1,363 @@
+/*
+ * exyswd-rng.c - Random Number Generator driver for the exynos
+ *
+ * Copyright (C) 2013 Samsung Electronics
+ * Sehee Kim <sehi.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/hw_random.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/smc.h>
+
+#define HWRNG_RET_OK			0
+#define HWRNG_RET_INVALID_ERROR		1
+#define HWRNG_RET_RETRY_ERROR		2
+#define HWRNG_RET_INVALID_FLAG_ERROR	3
+#define HWRNG_RET_TEST_ERROR		4
+#define HWRNG_RET_START_UP_TEST_DONE	5
+
+#define EXYRNG_MAX_FAILURES		25
+#define EXYRNG_START_UP_SIZE		(4096 + 1)
+#define EXYRNG_RETRY_MAX_COUNT		1000
+#define EXYRNG_START_UP_TEST_MAX_RETRY	2
+
+uint32_t hwrng_read_flag;
+static struct hwrng rng;
+
+spinlock_t hwrandom_lock;
+#if defined(CONFIG_EXYRNG_FAIL_POLICY_DISABLE)
+static int hwrng_disabled;
+#endif
+static int start_up_test;
+
+#ifdef CONFIG_EXYRNG_DEBUG
+#define exyrng_debug(args...)	printk(KERN_INFO args)
+#else
+#define exyrng_debug(args...)
+#endif
+
+void exynos_swd_test_fail(void)
+{
+#if defined(CONFIG_EXYRNG_FAIL_POLICY_DISABLE)
+	hwrng_disabled = 1;
+	printk("[ExyRNG] disabled for test failures\n");
+#else /* defined(CONFIG_EXYRNG_POLICY_RESET) */
+	panic("[ExyRNG] It failed to health tests. It means that it detects "
+	"the malfunction of TRNG(HW) which generates random numbers. If it "
+	"doesn't offer enough entropy, it should not be used. The system "
+	"reset could be a way to solve it. The health tests are designed "
+	"to have the false positive rate of approximately once per billion "
+	"based on min-entropy of TRNG.\n");
+#endif
+}
+
+static int exynos_swd_startup_test(void)
+{
+	uint32_t start_up_size;
+	uint32_t retry_cnt;
+	uint32_t test_cnt;
+	int ret = HWRNG_RET_OK;
+
+	start_up_size = EXYRNG_START_UP_SIZE;
+
+	retry_cnt = 0;
+	test_cnt = 1;
+	while (start_up_size) {
+		ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_GET_DATA, 1, 0);
+		if (ret == HWRNG_RET_RETRY_ERROR) {
+			if (retry_cnt++ > EXYRNG_RETRY_MAX_COUNT) {
+				printk("[ExyRNG] exceed retry in start-up test\n");
+				break;
+			}
+			usleep_range(50, 100);
+			continue;
+		}
+
+		if (ret == HWRNG_RET_TEST_ERROR) {
+#ifndef CONFIG_EXYRNG_USE_CRYPTOMANAGER
+			if (test_cnt < EXYRNG_START_UP_TEST_MAX_RETRY) {
+				start_up_size = EXYRNG_START_UP_SIZE;
+				test_cnt++;
+				printk("[ExyRNG] It performs start-up test "
+				"again to detect the malfunction of TRNG with "
+				"accuracy\n");
+				continue;
+			}
+#endif
+			exynos_swd_test_fail();
+			return -EFAULT;
+		}
+
+		/* start-up test is performed already */
+		if (ret == HWRNG_RET_START_UP_TEST_DONE) {
+			ret = HWRNG_RET_OK;
+			exyrng_debug("[ExyRNG] start-up test is already done\n");
+			break;
+		}
+
+		if (ret != HWRNG_RET_OK) {
+			exyrng_debug("[ExyRNG] failed to get random\n");
+			return -EFAULT;
+		}
+
+		if (start_up_size >= 32)
+			start_up_size -= 32;
+		else
+			start_up_size = 0;
+
+		retry_cnt = 0;
+	}
+
+	return ret;
+}
+
+static int exynos_swd_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	uint32_t *read_buf = data;
+	uint32_t read_size = max;
+	uint32_t r_data[2];
+	unsigned long flag;
+	uint32_t retry_cnt;
+	int ret = HWRNG_RET_OK;
+
+	register u64 reg0 __asm__("x0");
+	register u64 reg1 __asm__("x1");
+	register u64 reg2 __asm__("x2");
+	register u64 reg3 __asm__("x3");
+
+#if defined(CONFIG_EXYRNG_FAIL_POLICY_DISABLE)
+	if (hwrng_disabled)
+		return -EPERM;
+#endif
+
+	reg0 = 0;
+	reg1 = 0;
+	reg2 = 0;
+	reg3 = 0;
+
+	retry_cnt = 0;
+	do {
+		spin_lock_irqsave(&hwrandom_lock, flag);
+		if (hwrng_read_flag == 0) {
+			ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_INIT, 0, 0);
+			if (ret == HWRNG_RET_OK)
+				hwrng_read_flag = 1;
+			spin_unlock_irqrestore(&hwrandom_lock, flag);
+
+			if (ret == HWRNG_RET_RETRY_ERROR) {
+				if (retry_cnt++ > EXYRNG_RETRY_MAX_COUNT) {
+					printk("[ExyRNG] exceed retry in init\n");
+					break;
+				}
+				usleep_range(50, 100);
+			}
+		} else {
+			spin_unlock_irqrestore(&hwrandom_lock, flag);
+			break;
+		}
+	} while (ret == HWRNG_RET_RETRY_ERROR);
+	if (ret != HWRNG_RET_OK) {
+		msleep(1);
+		return -EFAULT;
+	}
+
+	if (start_up_test) {
+		ret = exynos_swd_startup_test();
+		if (ret != HWRNG_RET_OK)
+			goto out;
+
+		start_up_test = 0;
+		printk("[ExyRNG] passed the start-up test\n");
+	}
+
+	retry_cnt = 0;
+	while (read_size) {
+		spin_lock_irqsave(&hwrandom_lock, flag);
+		ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_GET_DATA, 0, 0);
+		__asm__ volatile(
+			"\t"
+			: "+r"(reg0), "+r"(reg1), "+r"(reg2), "+r"(reg3)
+		);
+		r_data[0] = (uint32_t)reg2;
+		r_data[1] = (uint32_t)reg3;
+		spin_unlock_irqrestore(&hwrandom_lock, flag);
+
+		if (ret == HWRNG_RET_RETRY_ERROR) {
+			if (retry_cnt++ > EXYRNG_RETRY_MAX_COUNT) {
+				ret = -EFAULT;
+				printk("[ExyRNG] exceed retry in read\n");
+				goto out;
+			}
+			usleep_range(50, 100);
+			continue;
+		}
+
+		if (ret == HWRNG_RET_TEST_ERROR) {
+			exyrng_debug("[ExyRNG] failed to continuous test\n");
+			ret = -EAGAIN;
+			goto out;
+		}
+
+		if (ret != HWRNG_RET_OK) {
+			ret = -EFAULT;
+			goto out;
+		}
+
+		*(uint32_t*)(read_buf++) = r_data[0];
+		*(uint32_t*)(read_buf++) = r_data[1];
+
+		read_size -= 8;
+		retry_cnt = 0;
+	}
+
+	ret = max;
+
+out:
+	retry_cnt = 0;
+	do {
+		spin_lock_irqsave(&hwrandom_lock, flag);
+		if (!exynos_smc(SMC_CMD_RANDOM, HWRNG_EXIT, 0, 0)) {
+			hwrng_read_flag = 0;
+			spin_unlock_irqrestore(&hwrandom_lock, flag);
+			break;
+		}
+		spin_unlock_irqrestore(&hwrandom_lock, flag);
+
+		if (retry_cnt++ > EXYRNG_RETRY_MAX_COUNT) {
+			printk("[ExyRNG] exceed retry in exit\n");
+			break;
+		}
+		usleep_range(50, 100);
+	} while(1);
+
+	return ret;
+}
+
+static int exyswd_rng_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	rng.name = "exyswd_rng";
+	rng.read = exynos_swd_read;
+	rng.quality = 500;
+
+	spin_lock_init(&hwrandom_lock);
+#if defined(CONFIG_EXYRNG_FIPS_COMPLIANCE)
+	start_up_test = 1;
+#endif
+
+	ret = hwrng_register(&rng);
+	if (ret)
+		return ret;
+
+	printk(KERN_INFO "ExyRNG: hwrng registered\n");
+
+	return 0;
+}
+
+static int exyswd_rng_remove(struct platform_device *pdev)
+{
+	hwrng_unregister(&rng);
+
+	return 0;
+}
+
+#if defined(CONFIG_PM_SLEEP) || defined(CONFIG_PM_RUNTIME)
+static int exyswd_rng_suspend(struct device *dev)
+{
+	unsigned long flag;
+	int ret = HWRNG_RET_OK;
+
+	spin_lock_irqsave(&hwrandom_lock, flag);
+	if (hwrng_read_flag) {
+		ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_EXIT, 0, 0);
+		if (ret != HWRNG_RET_OK)
+			printk("[ExyRNG] failed to enter suspend with %d\n", ret);
+	}
+	spin_unlock_irqrestore(&hwrandom_lock, flag);
+
+	return ret;
+}
+
+static int exyswd_rng_resume(struct device *dev)
+{
+	unsigned long flag;
+	int ret = HWRNG_RET_OK;
+
+	spin_lock_irqsave(&hwrandom_lock, flag);
+#if defined(CONFIG_EXYRNG_FIPS_COMPLIANCE)
+	ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_RESUME, 0, 0);
+	if (ret != HWRNG_RET_OK)
+		printk("[ExyRNG] failed to resume with %d\n", ret);
+#endif
+	if (hwrng_read_flag) {
+		ret = exynos_smc(SMC_CMD_RANDOM, HWRNG_INIT, 0, 0);
+		if (ret != HWRNG_RET_OK)
+			printk("[ExyRNG] failed to resume with %d\n", ret);
+	}
+	spin_unlock_irqrestore(&hwrandom_lock, flag);
+
+	return ret;
+}
+#endif
+
+static UNIVERSAL_DEV_PM_OPS(exyswd_rng_pm_ops, exyswd_rng_suspend, exyswd_rng_resume, NULL);
+
+static struct platform_driver exyswd_rng_driver = {
+	.probe		= exyswd_rng_probe,
+	.remove		= exyswd_rng_remove,
+	.driver		= {
+		.name	= "exyswd_rng",
+		.owner	= THIS_MODULE,
+		.pm     = &exyswd_rng_pm_ops,
+	},
+};
+
+static struct platform_device exyswd_rng_device = {
+	.name = "exyswd_rng",
+	.id = -1,
+};
+
+static int __init exyswd_rng_init(void)
+{
+	int ret;
+
+	ret = platform_device_register(&exyswd_rng_device);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&exyswd_rng_driver);
+	if (ret) {
+		platform_device_unregister(&exyswd_rng_device);
+		return ret;
+	}
+
+	printk(KERN_INFO "ExyRNG driver, (c) 2014 Samsung Electronics\n");
+
+	return 0;
+}
+
+static void __exit exyswd_rng_exit(void)
+{
+	platform_driver_unregister(&exyswd_rng_driver);
+	platform_device_unregister(&exyswd_rng_device);
+}
+
+module_init(exyswd_rng_init);
+module_exit(exyswd_rng_exit);
+
+MODULE_DESCRIPTION("EXYNOS H/W Random Number Generator driver");
+MODULE_AUTHOR("Sehee Kim <sehi.kim@samsung.com>");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/geode-rng.c

@@ -0,0 +1,139 @@
+/*
+ * RNG driver for AMD Geode RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+
+#define PFX	KBUILD_MODNAME ": "
+
+#define GEODE_RNG_DATA_REG   0x50
+#define GEODE_RNG_STATUS_REG 0x54
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id pci_tbl[] = {
+	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), 0, },
+	{ 0, },	/* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, pci_tbl);
+
+
+static int geode_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+
+	*data = readl(mem + GEODE_RNG_DATA_REG);
+
+	return 4;
+}
+
+static int geode_rng_data_present(struct hwrng *rng, int wait)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+	int data, i;
+
+	for (i = 0; i < 20; i++) {
+		data = !!(readl(mem + GEODE_RNG_STATUS_REG));
+		if (data || !wait)
+			break;
+		udelay(10);
+	}
+	return data;
+}
+
+
+static struct hwrng geode_rng = {
+	.name		= "geode",
+	.data_present	= geode_rng_data_present,
+	.data_read	= geode_rng_data_read,
+};
+
+
+static int __init mod_init(void)
+{
+	int err = -ENODEV;
+	struct pci_dev *pdev = NULL;
+	const struct pci_device_id *ent;
+	void __iomem *mem;
+	unsigned long rng_base;
+
+	for_each_pci_dev(pdev) {
+		ent = pci_match_id(pci_tbl, pdev);
+		if (ent)
+			goto found;
+	}
+	/* Device not found. */
+	goto out;
+
+found:
+	rng_base = pci_resource_start(pdev, 0);
+	if (rng_base == 0)
+		goto out;
+	err = -ENOMEM;
+	mem = ioremap(rng_base, 0x58);
+	if (!mem)
+		goto out;
+	geode_rng.priv = (unsigned long)mem;
+
+	pr_info("AMD Geode RNG detected\n");
+	err = hwrng_register(&geode_rng);
+	if (err) {
+		pr_err(PFX "RNG registering failed (%d)\n",
+		       err);
+		goto err_unmap;
+	}
+out:
+	return err;
+
+err_unmap:
+	iounmap(mem);
+	goto out;
+}
+
+static void __exit mod_exit(void)
+{
+	void __iomem *mem = (void __iomem *)geode_rng.priv;
+
+	hwrng_unregister(&geode_rng);
+	iounmap(mem);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_DESCRIPTION("H/W RNG driver for AMD Geode LX CPUs");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/intel-rng.c

@@ -0,0 +1,418 @@
+/*
+ * RNG driver for Intel RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/hw_random.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/stop_machine.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <asm/io.h>
+
+
+#define PFX	KBUILD_MODNAME ": "
+
+/*
+ * RNG registers
+ */
+#define INTEL_RNG_HW_STATUS			0
+#define         INTEL_RNG_PRESENT		0x40
+#define         INTEL_RNG_ENABLED		0x01
+#define INTEL_RNG_STATUS			1
+#define         INTEL_RNG_DATA_PRESENT		0x01
+#define INTEL_RNG_DATA				2
+
+/*
+ * Magic address at which Intel PCI bridges locate the RNG
+ */
+#define INTEL_RNG_ADDR				0xFFBC015F
+#define INTEL_RNG_ADDR_LEN			3
+
+/*
+ * LPC bridge PCI config space registers
+ */
+#define FWH_DEC_EN1_REG_OLD			0xe3
+#define FWH_DEC_EN1_REG_NEW			0xd9 /* high byte of 16-bit register */
+#define FWH_F8_EN_MASK				0x80
+
+#define BIOS_CNTL_REG_OLD			0x4e
+#define BIOS_CNTL_REG_NEW			0xdc
+#define BIOS_CNTL_WRITE_ENABLE_MASK		0x01
+#define BIOS_CNTL_LOCK_ENABLE_MASK		0x02
+
+/*
+ * Magic address at which Intel Firmware Hubs get accessed
+ */
+#define INTEL_FWH_ADDR				0xffff0000
+#define INTEL_FWH_ADDR_LEN			2
+
+/*
+ * Intel Firmware Hub command codes (write to any address inside the device)
+ */
+#define INTEL_FWH_RESET_CMD			0xff /* aka READ_ARRAY */
+#define INTEL_FWH_READ_ID_CMD			0x90
+
+/*
+ * Intel Firmware Hub Read ID command result addresses
+ */
+#define INTEL_FWH_MANUFACTURER_CODE_ADDRESS	0x000000
+#define INTEL_FWH_DEVICE_CODE_ADDRESS		0x000001
+
+/*
+ * Intel Firmware Hub Read ID command result values
+ */
+#define INTEL_FWH_MANUFACTURER_CODE		0x89
+#define INTEL_FWH_DEVICE_CODE_8M		0xac
+#define INTEL_FWH_DEVICE_CODE_4M		0xad
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id pci_tbl[] = {
+/* AA
+	{ PCI_DEVICE(0x8086, 0x2418) }, */
+	{ PCI_DEVICE(0x8086, 0x2410) }, /* AA */
+/* AB
+	{ PCI_DEVICE(0x8086, 0x2428) }, */
+	{ PCI_DEVICE(0x8086, 0x2420) }, /* AB */
+/* ??
+	{ PCI_DEVICE(0x8086, 0x2430) }, */
+/* BAM, CAM, DBM, FBM, GxM
+	{ PCI_DEVICE(0x8086, 0x2448) }, */
+	{ PCI_DEVICE(0x8086, 0x244c) }, /* BAM */
+	{ PCI_DEVICE(0x8086, 0x248c) }, /* CAM */
+	{ PCI_DEVICE(0x8086, 0x24cc) }, /* DBM */
+	{ PCI_DEVICE(0x8086, 0x2641) }, /* FBM */
+	{ PCI_DEVICE(0x8086, 0x27b9) }, /* GxM */
+	{ PCI_DEVICE(0x8086, 0x27bd) }, /* GxM DH */
+/* BA, CA, DB, Ex, 6300, Fx, 631x/632x, Gx
+	{ PCI_DEVICE(0x8086, 0x244e) }, */
+	{ PCI_DEVICE(0x8086, 0x2440) }, /* BA */
+	{ PCI_DEVICE(0x8086, 0x2480) }, /* CA */
+	{ PCI_DEVICE(0x8086, 0x24c0) }, /* DB */
+	{ PCI_DEVICE(0x8086, 0x24d0) }, /* Ex */
+	{ PCI_DEVICE(0x8086, 0x25a1) }, /* 6300 */
+	{ PCI_DEVICE(0x8086, 0x2640) }, /* Fx */
+	{ PCI_DEVICE(0x8086, 0x2670) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2671) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2672) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2673) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2674) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2675) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2676) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2677) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2678) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x2679) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267a) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267b) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267c) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267d) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267e) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x267f) }, /* 631x/632x */
+	{ PCI_DEVICE(0x8086, 0x27b8) }, /* Gx */
+/* E
+	{ PCI_DEVICE(0x8086, 0x245e) }, */
+	{ PCI_DEVICE(0x8086, 0x2450) }, /* E  */
+	{ 0, },	/* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, pci_tbl);
+
+static __initdata int no_fwh_detect;
+module_param(no_fwh_detect, int, 0);
+MODULE_PARM_DESC(no_fwh_detect, "Skip FWH detection:\n"
+                                " positive value - skip if FWH space locked read-only\n"
+                                " negative value - skip always");
+
+static inline u8 hwstatus_get(void __iomem *mem)
+{
+	return readb(mem + INTEL_RNG_HW_STATUS);
+}
+
+static inline u8 hwstatus_set(void __iomem *mem,
+			      u8 hw_status)
+{
+	writeb(hw_status, mem + INTEL_RNG_HW_STATUS);
+	return hwstatus_get(mem);
+}
+
+static int intel_rng_data_present(struct hwrng *rng, int wait)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+	int data, i;
+
+	for (i = 0; i < 20; i++) {
+		data = !!(readb(mem + INTEL_RNG_STATUS) &
+			  INTEL_RNG_DATA_PRESENT);
+		if (data || !wait)
+			break;
+		udelay(10);
+	}
+	return data;
+}
+
+static int intel_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+
+	*data = readb(mem + INTEL_RNG_DATA);
+
+	return 1;
+}
+
+static int intel_rng_init(struct hwrng *rng)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+	u8 hw_status;
+	int err = -EIO;
+
+	hw_status = hwstatus_get(mem);
+	/* turn RNG h/w on, if it's off */
+	if ((hw_status & INTEL_RNG_ENABLED) == 0)
+		hw_status = hwstatus_set(mem, hw_status | INTEL_RNG_ENABLED);
+	if ((hw_status & INTEL_RNG_ENABLED) == 0) {
+		pr_err(PFX "cannot enable RNG, aborting\n");
+		goto out;
+	}
+	err = 0;
+out:
+	return err;
+}
+
+static void intel_rng_cleanup(struct hwrng *rng)
+{
+	void __iomem *mem = (void __iomem *)rng->priv;
+	u8 hw_status;
+
+	hw_status = hwstatus_get(mem);
+	if (hw_status & INTEL_RNG_ENABLED)
+		hwstatus_set(mem, hw_status & ~INTEL_RNG_ENABLED);
+	else
+		pr_warn(PFX "unusual: RNG already disabled\n");
+}
+
+
+static struct hwrng intel_rng = {
+	.name		= "intel",
+	.init		= intel_rng_init,
+	.cleanup	= intel_rng_cleanup,
+	.data_present	= intel_rng_data_present,
+	.data_read	= intel_rng_data_read,
+};
+
+struct intel_rng_hw {
+	struct pci_dev *dev;
+	void __iomem *mem;
+	u8 bios_cntl_off;
+	u8 bios_cntl_val;
+	u8 fwh_dec_en1_off;
+	u8 fwh_dec_en1_val;
+};
+
+static int __init intel_rng_hw_init(void *_intel_rng_hw)
+{
+	struct intel_rng_hw *intel_rng_hw = _intel_rng_hw;
+	u8 mfc, dvc;
+
+	/* interrupts disabled in stop_machine call */
+
+	if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK))
+		pci_write_config_byte(intel_rng_hw->dev,
+		                      intel_rng_hw->fwh_dec_en1_off,
+		                      intel_rng_hw->fwh_dec_en1_val |
+				      FWH_F8_EN_MASK);
+	if (!(intel_rng_hw->bios_cntl_val & BIOS_CNTL_WRITE_ENABLE_MASK))
+		pci_write_config_byte(intel_rng_hw->dev,
+		                      intel_rng_hw->bios_cntl_off,
+		                      intel_rng_hw->bios_cntl_val |
+				      BIOS_CNTL_WRITE_ENABLE_MASK);
+
+	writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem);
+	writeb(INTEL_FWH_READ_ID_CMD, intel_rng_hw->mem);
+	mfc = readb(intel_rng_hw->mem + INTEL_FWH_MANUFACTURER_CODE_ADDRESS);
+	dvc = readb(intel_rng_hw->mem + INTEL_FWH_DEVICE_CODE_ADDRESS);
+	writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem);
+
+	if (!(intel_rng_hw->bios_cntl_val &
+	      (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)))
+		pci_write_config_byte(intel_rng_hw->dev,
+				      intel_rng_hw->bios_cntl_off,
+				      intel_rng_hw->bios_cntl_val);
+	if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK))
+		pci_write_config_byte(intel_rng_hw->dev,
+				      intel_rng_hw->fwh_dec_en1_off,
+				      intel_rng_hw->fwh_dec_en1_val);
+
+	if (mfc != INTEL_FWH_MANUFACTURER_CODE ||
+	    (dvc != INTEL_FWH_DEVICE_CODE_8M &&
+	     dvc != INTEL_FWH_DEVICE_CODE_4M)) {
+		pr_notice(PFX "FWH not detected\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int __init intel_init_hw_struct(struct intel_rng_hw *intel_rng_hw,
+					struct pci_dev *dev)
+{
+	intel_rng_hw->bios_cntl_val = 0xff;
+	intel_rng_hw->fwh_dec_en1_val = 0xff;
+	intel_rng_hw->dev = dev;
+
+	/* Check for Intel 82802 */
+	if (dev->device < 0x2640) {
+		intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_OLD;
+		intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_OLD;
+	} else {
+		intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_NEW;
+		intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_NEW;
+	}
+
+	pci_read_config_byte(dev, intel_rng_hw->fwh_dec_en1_off,
+			     &intel_rng_hw->fwh_dec_en1_val);
+	pci_read_config_byte(dev, intel_rng_hw->bios_cntl_off,
+			     &intel_rng_hw->bios_cntl_val);
+
+	if ((intel_rng_hw->bios_cntl_val &
+	     (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK))
+	    == BIOS_CNTL_LOCK_ENABLE_MASK) {
+		static __initdata /*const*/ char warning[] =
+PFX "Firmware space is locked read-only. If you can't or\n"
+PFX "don't want to disable this in firmware setup, and if\n"
+PFX "you are certain that your system has a functional\n"
+PFX "RNG, try using the 'no_fwh_detect' option.\n";
+
+		if (no_fwh_detect)
+			return -ENODEV;
+		pr_warn("%s", warning);
+		return -EBUSY;
+	}
+
+	intel_rng_hw->mem = ioremap_nocache(INTEL_FWH_ADDR, INTEL_FWH_ADDR_LEN);
+	if (intel_rng_hw->mem == NULL)
+		return -EBUSY;
+
+	return 0;
+}
+
+
+static int __init mod_init(void)
+{
+	int err = -ENODEV;
+	int i;
+	struct pci_dev *dev = NULL;
+	void __iomem *mem = mem;
+	u8 hw_status;
+	struct intel_rng_hw *intel_rng_hw;
+
+	for (i = 0; !dev && pci_tbl[i].vendor; ++i)
+		dev = pci_get_device(pci_tbl[i].vendor, pci_tbl[i].device,
+				     NULL);
+
+	if (!dev)
+		goto out; /* Device not found. */
+
+	if (no_fwh_detect < 0) {
+		pci_dev_put(dev);
+		goto fwh_done;
+	}
+
+	intel_rng_hw = kmalloc(sizeof(*intel_rng_hw), GFP_KERNEL);
+	if (!intel_rng_hw) {
+		pci_dev_put(dev);
+		goto out;
+	}
+
+	err = intel_init_hw_struct(intel_rng_hw, dev);
+	if (err) {
+		pci_dev_put(dev);
+		kfree(intel_rng_hw);
+		if (err == -ENODEV)
+			goto fwh_done;
+		goto out;
+	}
+
+	/*
+	 * Since the BIOS code/data is going to disappear from its normal
+	 * location with the Read ID command, all activity on the system
+	 * must be stopped until the state is back to normal.
+	 *
+	 * Use stop_machine because IPIs can be blocked by disabling
+	 * interrupts.
+	 */
+	err = stop_machine(intel_rng_hw_init, intel_rng_hw, NULL);
+	pci_dev_put(dev);
+	iounmap(intel_rng_hw->mem);
+	kfree(intel_rng_hw);
+	if (err)
+		goto out;
+
+fwh_done:
+	err = -ENOMEM;
+	mem = ioremap(INTEL_RNG_ADDR, INTEL_RNG_ADDR_LEN);
+	if (!mem)
+		goto out;
+	intel_rng.priv = (unsigned long)mem;
+
+	/* Check for Random Number Generator */
+	err = -ENODEV;
+	hw_status = hwstatus_get(mem);
+	if ((hw_status & INTEL_RNG_PRESENT) == 0) {
+		iounmap(mem);
+		goto out;
+	}
+
+	pr_info("Intel 82802 RNG detected\n");
+	err = hwrng_register(&intel_rng);
+	if (err) {
+		pr_err(PFX "RNG registering failed (%d)\n",
+		       err);
+		iounmap(mem);
+	}
+out:
+	return err;
+
+}
+
+static void __exit mod_exit(void)
+{
+	void __iomem *mem = (void __iomem *)intel_rng.priv;
+
+	hwrng_unregister(&intel_rng);
+	iounmap(mem);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+MODULE_DESCRIPTION("H/W RNG driver for Intel chipsets");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/ixp4xx-rng.c

@@ -0,0 +1,75 @@
+/*
+ * drivers/char/hw_random/ixp4xx-rng.c
+ *
+ * RNG driver for Intel IXP4xx family of NPUs
+ *
+ * Author: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * Fixes by Michael Buesch
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/hw_random.h>
+
+#include <asm/io.h>
+#include <mach/hardware.h>
+
+
+static int ixp4xx_rng_data_read(struct hwrng *rng, u32 *buffer)
+{
+	void __iomem * rng_base = (void __iomem *)rng->priv;
+
+	*buffer = __raw_readl(rng_base);
+
+	return 4;
+}
+
+static struct hwrng ixp4xx_rng_ops = {
+	.name		= "ixp4xx",
+	.data_read	= ixp4xx_rng_data_read,
+};
+
+static int __init ixp4xx_rng_init(void)
+{
+	void __iomem * rng_base;
+	int err;
+
+	if (!cpu_is_ixp46x()) /* includes IXP455 */
+		return -ENOSYS;
+
+	rng_base = ioremap(0x70002100, 4);
+	if (!rng_base)
+		return -ENOMEM;
+	ixp4xx_rng_ops.priv = (unsigned long)rng_base;
+	err = hwrng_register(&ixp4xx_rng_ops);
+	if (err)
+		iounmap(rng_base);
+
+	return err;
+}
+
+static void __exit ixp4xx_rng_exit(void)
+{
+	void __iomem * rng_base = (void __iomem *)ixp4xx_rng_ops.priv;
+
+	hwrng_unregister(&ixp4xx_rng_ops);
+	iounmap(rng_base);
+}
+
+module_init(ixp4xx_rng_init);
+module_exit(ixp4xx_rng_exit);
+
+MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
+MODULE_DESCRIPTION("H/W Pseudo-Random Number Generator (RNG) driver for IXP45x/46x");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/msm-rng.c

@@ -0,0 +1,197 @@
+/*
+ * Copyright (c) 2011-2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/* Device specific register offsets */
+#define PRNG_DATA_OUT		0x0000
+#define PRNG_STATUS		0x0004
+#define PRNG_LFSR_CFG		0x0100
+#define PRNG_CONFIG		0x0104
+
+/* Device specific register masks and config values */
+#define PRNG_LFSR_CFG_MASK	0x0000ffff
+#define PRNG_LFSR_CFG_CLOCKS	0x0000dddd
+#define PRNG_CONFIG_HW_ENABLE	BIT(1)
+#define PRNG_STATUS_DATA_AVAIL	BIT(0)
+
+#define MAX_HW_FIFO_DEPTH	16
+#define MAX_HW_FIFO_SIZE	(MAX_HW_FIFO_DEPTH * 4)
+#define WORD_SZ			4
+
+struct msm_rng {
+	void __iomem *base;
+	struct clk *clk;
+	struct hwrng hwrng;
+};
+
+#define to_msm_rng(p)	container_of(p, struct msm_rng, hwrng)
+
+static int msm_rng_enable(struct hwrng *hwrng, int enable)
+{
+	struct msm_rng *rng = to_msm_rng(hwrng);
+	u32 val;
+	int ret;
+
+	ret = clk_prepare_enable(rng->clk);
+	if (ret)
+		return ret;
+
+	if (enable) {
+		/* Enable PRNG only if it is not already enabled */
+		val = readl_relaxed(rng->base + PRNG_CONFIG);
+		if (val & PRNG_CONFIG_HW_ENABLE)
+			goto already_enabled;
+
+		val = readl_relaxed(rng->base + PRNG_LFSR_CFG);
+		val &= ~PRNG_LFSR_CFG_MASK;
+		val |= PRNG_LFSR_CFG_CLOCKS;
+		writel(val, rng->base + PRNG_LFSR_CFG);
+
+		val = readl_relaxed(rng->base + PRNG_CONFIG);
+		val |= PRNG_CONFIG_HW_ENABLE;
+		writel(val, rng->base + PRNG_CONFIG);
+	} else {
+		val = readl_relaxed(rng->base + PRNG_CONFIG);
+		val &= ~PRNG_CONFIG_HW_ENABLE;
+		writel(val, rng->base + PRNG_CONFIG);
+	}
+
+already_enabled:
+	clk_disable_unprepare(rng->clk);
+	return 0;
+}
+
+static int msm_rng_read(struct hwrng *hwrng, void *data, size_t max, bool wait)
+{
+	struct msm_rng *rng = to_msm_rng(hwrng);
+	size_t currsize = 0;
+	u32 *retdata = data;
+	size_t maxsize;
+	int ret;
+	u32 val;
+
+	/* calculate max size bytes to transfer back to caller */
+	maxsize = min_t(size_t, MAX_HW_FIFO_SIZE, max);
+
+	/* no room for word data */
+	if (maxsize < WORD_SZ)
+		return 0;
+
+	ret = clk_prepare_enable(rng->clk);
+	if (ret)
+		return ret;
+
+	/* read random data from hardware */
+	do {
+		val = readl_relaxed(rng->base + PRNG_STATUS);
+		if (!(val & PRNG_STATUS_DATA_AVAIL))
+			break;
+
+		val = readl_relaxed(rng->base + PRNG_DATA_OUT);
+		if (!val)
+			break;
+
+		*retdata++ = val;
+		currsize += WORD_SZ;
+
+		/* make sure we stay on 32bit boundary */
+		if ((maxsize - currsize) < WORD_SZ)
+			break;
+	} while (currsize < maxsize);
+
+	clk_disable_unprepare(rng->clk);
+
+	return currsize;
+}
+
+static int msm_rng_init(struct hwrng *hwrng)
+{
+	return msm_rng_enable(hwrng, 1);
+}
+
+static void msm_rng_cleanup(struct hwrng *hwrng)
+{
+	msm_rng_enable(hwrng, 0);
+}
+
+static int msm_rng_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct msm_rng *rng;
+	int ret;
+
+	rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+	if (!rng)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, rng);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	rng->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(rng->base))
+		return PTR_ERR(rng->base);
+
+	rng->clk = devm_clk_get(&pdev->dev, "core");
+	if (IS_ERR(rng->clk))
+		return PTR_ERR(rng->clk);
+
+	rng->hwrng.name = KBUILD_MODNAME,
+	rng->hwrng.init = msm_rng_init,
+	rng->hwrng.cleanup = msm_rng_cleanup,
+	rng->hwrng.read = msm_rng_read,
+
+	ret = hwrng_register(&rng->hwrng);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register hwrng\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int msm_rng_remove(struct platform_device *pdev)
+{
+	struct msm_rng *rng = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&rng->hwrng);
+	return 0;
+}
+
+static const struct of_device_id msm_rng_of_match[] = {
+	{ .compatible = "qcom,prng", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, msm_rng_of_match);
+
+static struct platform_driver msm_rng_driver = {
+	.probe = msm_rng_probe,
+	.remove = msm_rng_remove,
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(msm_rng_of_match),
+	}
+};
+module_platform_driver(msm_rng_driver);
+
+MODULE_ALIAS("platform:" KBUILD_MODNAME);
+MODULE_AUTHOR("The Linux Foundation");
+MODULE_DESCRIPTION("Qualcomm MSM random number generator driver");
+MODULE_LICENSE("GPL v2");

drivers/char/hw_random/mxc-rnga.c

@@ -0,0 +1,218 @@
+/*
+ * RNG driver for Freescale RNGA
+ *
+ * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Author: Alan Carvalho de Assis <acassis@gmail.com>
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * This driver is based on other RNG drivers.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+
+/* RNGA Registers */
+#define RNGA_CONTROL			0x00
+#define RNGA_STATUS			0x04
+#define RNGA_ENTROPY			0x08
+#define RNGA_OUTPUT_FIFO		0x0c
+#define RNGA_MODE			0x10
+#define RNGA_VERIFICATION_CONTROL	0x14
+#define RNGA_OSC_CONTROL_COUNTER	0x18
+#define RNGA_OSC1_COUNTER		0x1c
+#define RNGA_OSC2_COUNTER		0x20
+#define RNGA_OSC_COUNTER_STATUS		0x24
+
+/* RNGA Registers Range */
+#define RNG_ADDR_RANGE			0x28
+
+/* RNGA Control Register */
+#define RNGA_CONTROL_SLEEP		0x00000010
+#define RNGA_CONTROL_CLEAR_INT		0x00000008
+#define RNGA_CONTROL_MASK_INTS		0x00000004
+#define RNGA_CONTROL_HIGH_ASSURANCE	0x00000002
+#define RNGA_CONTROL_GO			0x00000001
+
+#define RNGA_STATUS_LEVEL_MASK		0x0000ff00
+
+/* RNGA Status Register */
+#define RNGA_STATUS_OSC_DEAD		0x80000000
+#define RNGA_STATUS_SLEEP		0x00000010
+#define RNGA_STATUS_ERROR_INT		0x00000008
+#define RNGA_STATUS_FIFO_UNDERFLOW	0x00000004
+#define RNGA_STATUS_LAST_READ_STATUS	0x00000002
+#define RNGA_STATUS_SECURITY_VIOLATION	0x00000001
+
+struct mxc_rng {
+	struct device *dev;
+	struct hwrng rng;
+	void __iomem *mem;
+	struct clk *clk;
+};
+
+static int mxc_rnga_data_present(struct hwrng *rng, int wait)
+{
+	int i;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
+
+	for (i = 0; i < 20; i++) {
+		/* how many random numbers are in FIFO? [0-16] */
+		int level = (__raw_readl(mxc_rng->mem + RNGA_STATUS) &
+				RNGA_STATUS_LEVEL_MASK) >> 8;
+		if (level || !wait)
+			return !!level;
+		udelay(10);
+	}
+	return 0;
+}
+
+static int mxc_rnga_data_read(struct hwrng *rng, u32 * data)
+{
+	int err;
+	u32 ctrl;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
+
+	/* retrieve a random number from FIFO */
+	*data = __raw_readl(mxc_rng->mem + RNGA_OUTPUT_FIFO);
+
+	/* some error while reading this random number? */
+	err = __raw_readl(mxc_rng->mem + RNGA_STATUS) & RNGA_STATUS_ERROR_INT;
+
+	/* if error: clear error interrupt, but doesn't return random number */
+	if (err) {
+		dev_dbg(mxc_rng->dev, "Error while reading random number!\n");
+		ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+		__raw_writel(ctrl | RNGA_CONTROL_CLEAR_INT,
+					mxc_rng->mem + RNGA_CONTROL);
+		return 0;
+	} else
+		return 4;
+}
+
+static int mxc_rnga_init(struct hwrng *rng)
+{
+	u32 ctrl, osc;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
+
+	/* wake up */
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+	__raw_writel(ctrl & ~RNGA_CONTROL_SLEEP, mxc_rng->mem + RNGA_CONTROL);
+
+	/* verify if oscillator is working */
+	osc = __raw_readl(mxc_rng->mem + RNGA_STATUS);
+	if (osc & RNGA_STATUS_OSC_DEAD) {
+		dev_err(mxc_rng->dev, "RNGA Oscillator is dead!\n");
+		return -ENODEV;
+	}
+
+	/* go running */
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+	__raw_writel(ctrl | RNGA_CONTROL_GO, mxc_rng->mem + RNGA_CONTROL);
+
+	return 0;
+}
+
+static void mxc_rnga_cleanup(struct hwrng *rng)
+{
+	u32 ctrl;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
+
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+
+	/* stop rnga */
+	__raw_writel(ctrl & ~RNGA_CONTROL_GO, mxc_rng->mem + RNGA_CONTROL);
+}
+
+static int __init mxc_rnga_probe(struct platform_device *pdev)
+{
+	int err = -ENODEV;
+	struct resource *res;
+	struct mxc_rng *mxc_rng;
+
+	mxc_rng = devm_kzalloc(&pdev->dev, sizeof(struct mxc_rng),
+					GFP_KERNEL);
+	if (!mxc_rng)
+		return -ENOMEM;
+
+	mxc_rng->dev = &pdev->dev;
+	mxc_rng->rng.name = "mxc-rnga";
+	mxc_rng->rng.init = mxc_rnga_init;
+	mxc_rng->rng.cleanup = mxc_rnga_cleanup,
+	mxc_rng->rng.data_present = mxc_rnga_data_present,
+	mxc_rng->rng.data_read = mxc_rnga_data_read,
+
+	mxc_rng->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(mxc_rng->clk)) {
+		dev_err(&pdev->dev, "Could not get rng_clk!\n");
+		err = PTR_ERR(mxc_rng->clk);
+		goto out;
+	}
+
+	err = clk_prepare_enable(mxc_rng->clk);
+	if (err)
+		goto out;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mxc_rng->mem = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mxc_rng->mem)) {
+		err = PTR_ERR(mxc_rng->mem);
+		goto err_ioremap;
+	}
+
+	err = hwrng_register(&mxc_rng->rng);
+	if (err) {
+		dev_err(&pdev->dev, "MXC RNGA registering failed (%d)\n", err);
+		goto err_ioremap;
+	}
+
+	dev_info(&pdev->dev, "MXC RNGA Registered.\n");
+
+	return 0;
+
+err_ioremap:
+	clk_disable_unprepare(mxc_rng->clk);
+
+out:
+	return err;
+}
+
+static int __exit mxc_rnga_remove(struct platform_device *pdev)
+{
+	struct mxc_rng *mxc_rng = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&mxc_rng->rng);
+
+	clk_disable_unprepare(mxc_rng->clk);
+
+	return 0;
+}
+
+static struct platform_driver mxc_rnga_driver = {
+	.driver = {
+		   .name = "mxc_rnga",
+		   .owner = THIS_MODULE,
+		   },
+	.remove = __exit_p(mxc_rnga_remove),
+};
+
+module_platform_driver_probe(mxc_rnga_driver, mxc_rnga_probe);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("H/W RNGA driver for i.MX");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/n2-asm.S

@@ -0,0 +1,79 @@
+/* n2-asm.S: Niagara2 RNG hypervisor call assembler.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+#include <linux/linkage.h>
+#include <asm/hypervisor.h>
+#include "n2rng.h"
+
+	.text
+
+ENTRY(sun4v_rng_get_diag_ctl)
+	mov	HV_FAST_RNG_GET_DIAG_CTL, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 nop
+ENDPROC(sun4v_rng_get_diag_ctl)
+
+ENTRY(sun4v_rng_ctl_read_v1)
+	mov	%o1, %o3
+	mov	%o2, %o4
+	mov	HV_FAST_RNG_CTL_READ, %o5
+	ta	HV_FAST_TRAP
+	stx	%o1, [%o3]
+	retl
+	 stx	%o2, [%o4]
+ENDPROC(sun4v_rng_ctl_read_v1)
+
+ENTRY(sun4v_rng_ctl_read_v2)
+	save	%sp, -192, %sp
+	mov	%i0, %o0
+	mov	%i1, %o1
+	mov	HV_FAST_RNG_CTL_READ, %o5
+	ta	HV_FAST_TRAP
+	stx	%o1, [%i2]
+	stx	%o2, [%i3]
+	stx	%o3, [%i4]
+	stx	%o4, [%i5]
+	ret
+	restore	%g0, %o0, %o0
+ENDPROC(sun4v_rng_ctl_read_v2)
+
+ENTRY(sun4v_rng_ctl_write_v1)
+	mov	%o3, %o4
+	mov	HV_FAST_RNG_CTL_WRITE, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 stx	%o1, [%o4]
+ENDPROC(sun4v_rng_ctl_write_v1)
+
+ENTRY(sun4v_rng_ctl_write_v2)
+	mov	HV_FAST_RNG_CTL_WRITE, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 nop
+ENDPROC(sun4v_rng_ctl_write_v2)
+
+ENTRY(sun4v_rng_data_read_diag_v1)
+	mov	%o2, %o4
+	mov	HV_FAST_RNG_DATA_READ_DIAG, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 stx	%o1, [%o4]
+ENDPROC(sun4v_rng_data_read_diag_v1)
+
+ENTRY(sun4v_rng_data_read_diag_v2)
+	mov	%o3, %o4
+	mov	HV_FAST_RNG_DATA_READ_DIAG, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 stx	%o1, [%o4]
+ENDPROC(sun4v_rng_data_read_diag_v2)
+
+ENTRY(sun4v_rng_data_read)
+	mov	%o1, %o4
+	mov	HV_FAST_RNG_DATA_READ, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 stx	%o1, [%o4]
+ENDPROC(sun4v_rng_data_read)

drivers/char/hw_random/n2-drv.c

@@ -0,0 +1,760 @@
+/* n2-drv.c: Niagara-2 RNG driver.
+ *
+ * Copyright (C) 2008, 2011 David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/preempt.h>
+#include <linux/hw_random.h>
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <asm/hypervisor.h>
+
+#include "n2rng.h"
+
+#define DRV_MODULE_NAME		"n2rng"
+#define PFX DRV_MODULE_NAME	": "
+#define DRV_MODULE_VERSION	"0.2"
+#define DRV_MODULE_RELDATE	"July 27, 2011"
+
+static char version[] =
+	DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
+
+MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
+MODULE_DESCRIPTION("Niagara2 RNG driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_MODULE_VERSION);
+
+/* The Niagara2 RNG provides a 64-bit read-only random number
+ * register, plus a control register.  Access to the RNG is
+ * virtualized through the hypervisor so that both guests and control
+ * nodes can access the device.
+ *
+ * The entropy source consists of raw entropy sources, each
+ * constructed from a voltage controlled oscillator whose phase is
+ * jittered by thermal noise sources.
+ *
+ * The oscillator in each of the three raw entropy sources run at
+ * different frequencies.  Normally, all three generator outputs are
+ * gathered, xored together, and fed into a CRC circuit, the output of
+ * which is the 64-bit read-only register.
+ *
+ * Some time is necessary for all the necessary entropy to build up
+ * such that a full 64-bits of entropy are available in the register.
+ * In normal operating mode (RNG_CTL_LFSR is set), the chip implements
+ * an interlock which blocks register reads until sufficient entropy
+ * is available.
+ *
+ * A control register is provided for adjusting various aspects of RNG
+ * operation, and to enable diagnostic modes.  Each of the three raw
+ * entropy sources has an enable bit (RNG_CTL_ES{1,2,3}).  Also
+ * provided are fields for controlling the minimum time in cycles
+ * between read accesses to the register (RNG_CTL_WAIT, this controls
+ * the interlock described in the previous paragraph).
+ *
+ * The standard setting is to have the mode bit (RNG_CTL_LFSR) set,
+ * all three entropy sources enabled, and the interlock time set
+ * appropriately.
+ *
+ * The CRC polynomial used by the chip is:
+ *
+ * P(X) = x64 + x61 + x57 + x56 + x52 + x51 + x50 + x48 + x47 + x46 +
+ *        x43 + x42 + x41 + x39 + x38 + x37 + x35 + x32 + x28 + x25 +
+ *        x22 + x21 + x17 + x15 + x13 + x12 + x11 + x7 + x5 + x + 1
+ *
+ * The RNG_CTL_VCO value of each noise cell must be programmed
+ * separately.  This is why 4 control register values must be provided
+ * to the hypervisor.  During a write, the hypervisor writes them all,
+ * one at a time, to the actual RNG_CTL register.  The first three
+ * values are used to setup the desired RNG_CTL_VCO for each entropy
+ * source, for example:
+ *
+ *	control 0: (1 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES1
+ *	control 1: (2 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES2
+ *	control 2: (3 << RNG_CTL_VCO_SHIFT) | RNG_CTL_ES3
+ *
+ * And then the fourth value sets the final chip state and enables
+ * desired.
+ */
+
+static int n2rng_hv_err_trans(unsigned long hv_err)
+{
+	switch (hv_err) {
+	case HV_EOK:
+		return 0;
+	case HV_EWOULDBLOCK:
+		return -EAGAIN;
+	case HV_ENOACCESS:
+		return -EPERM;
+	case HV_EIO:
+		return -EIO;
+	case HV_EBUSY:
+		return -EBUSY;
+	case HV_EBADALIGN:
+	case HV_ENORADDR:
+		return -EFAULT;
+	default:
+		return -EINVAL;
+	}
+}
+
+static unsigned long n2rng_generic_read_control_v2(unsigned long ra,
+						   unsigned long unit)
+{
+	unsigned long hv_err, state, ticks, watchdog_delta, watchdog_status;
+	int block = 0, busy = 0;
+
+	while (1) {
+		hv_err = sun4v_rng_ctl_read_v2(ra, unit, &state,
+					       &ticks,
+					       &watchdog_delta,
+					       &watchdog_status);
+		if (hv_err == HV_EOK)
+			break;
+
+		if (hv_err == HV_EBUSY) {
+			if (++busy >= N2RNG_BUSY_LIMIT)
+				break;
+
+			udelay(1);
+		} else if (hv_err == HV_EWOULDBLOCK) {
+			if (++block >= N2RNG_BLOCK_LIMIT)
+				break;
+
+			__delay(ticks);
+		} else
+			break;
+	}
+
+	return hv_err;
+}
+
+/* In multi-socket situations, the hypervisor might need to
+ * queue up the RNG control register write if it's for a unit
+ * that is on a cpu socket other than the one we are executing on.
+ *
+ * We poll here waiting for a successful read of that control
+ * register to make sure the write has been actually performed.
+ */
+static unsigned long n2rng_control_settle_v2(struct n2rng *np, int unit)
+{
+	unsigned long ra = __pa(&np->scratch_control[0]);
+
+	return n2rng_generic_read_control_v2(ra, unit);
+}
+
+static unsigned long n2rng_write_ctl_one(struct n2rng *np, int unit,
+					 unsigned long state,
+					 unsigned long control_ra,
+					 unsigned long watchdog_timeout,
+					 unsigned long *ticks)
+{
+	unsigned long hv_err;
+
+	if (np->hvapi_major == 1) {
+		hv_err = sun4v_rng_ctl_write_v1(control_ra, state,
+						watchdog_timeout, ticks);
+	} else {
+		hv_err = sun4v_rng_ctl_write_v2(control_ra, state,
+						watchdog_timeout, unit);
+		if (hv_err == HV_EOK)
+			hv_err = n2rng_control_settle_v2(np, unit);
+		*ticks = N2RNG_ACCUM_CYCLES_DEFAULT;
+	}
+
+	return hv_err;
+}
+
+static int n2rng_generic_read_data(unsigned long data_ra)
+{
+	unsigned long ticks, hv_err;
+	int block = 0, hcheck = 0;
+
+	while (1) {
+		hv_err = sun4v_rng_data_read(data_ra, &ticks);
+		if (hv_err == HV_EOK)
+			return 0;
+
+		if (hv_err == HV_EWOULDBLOCK) {
+			if (++block >= N2RNG_BLOCK_LIMIT)
+				return -EWOULDBLOCK;
+			__delay(ticks);
+		} else if (hv_err == HV_ENOACCESS) {
+			return -EPERM;
+		} else if (hv_err == HV_EIO) {
+			if (++hcheck >= N2RNG_HCHECK_LIMIT)
+				return -EIO;
+			udelay(10000);
+		} else
+			return -ENODEV;
+	}
+}
+
+static unsigned long n2rng_read_diag_data_one(struct n2rng *np,
+					      unsigned long unit,
+					      unsigned long data_ra,
+					      unsigned long data_len,
+					      unsigned long *ticks)
+{
+	unsigned long hv_err;
+
+	if (np->hvapi_major == 1) {
+		hv_err = sun4v_rng_data_read_diag_v1(data_ra, data_len, ticks);
+	} else {
+		hv_err = sun4v_rng_data_read_diag_v2(data_ra, data_len,
+						     unit, ticks);
+		if (!*ticks)
+			*ticks = N2RNG_ACCUM_CYCLES_DEFAULT;
+	}
+	return hv_err;
+}
+
+static int n2rng_generic_read_diag_data(struct n2rng *np,
+					unsigned long unit,
+					unsigned long data_ra,
+					unsigned long data_len)
+{
+	unsigned long ticks, hv_err;
+	int block = 0;
+
+	while (1) {
+		hv_err = n2rng_read_diag_data_one(np, unit,
+						  data_ra, data_len,
+						  &ticks);
+		if (hv_err == HV_EOK)
+			return 0;
+
+		if (hv_err == HV_EWOULDBLOCK) {
+			if (++block >= N2RNG_BLOCK_LIMIT)
+				return -EWOULDBLOCK;
+			__delay(ticks);
+		} else if (hv_err == HV_ENOACCESS) {
+			return -EPERM;
+		} else if (hv_err == HV_EIO) {
+			return -EIO;
+		} else
+			return -ENODEV;
+	}
+}
+
+
+static int n2rng_generic_write_control(struct n2rng *np,
+				       unsigned long control_ra,
+				       unsigned long unit,
+				       unsigned long state)
+{
+	unsigned long hv_err, ticks;
+	int block = 0, busy = 0;
+
+	while (1) {
+		hv_err = n2rng_write_ctl_one(np, unit, state, control_ra,
+					     np->wd_timeo, &ticks);
+		if (hv_err == HV_EOK)
+			return 0;
+
+		if (hv_err == HV_EWOULDBLOCK) {
+			if (++block >= N2RNG_BLOCK_LIMIT)
+				return -EWOULDBLOCK;
+			__delay(ticks);
+		} else if (hv_err == HV_EBUSY) {
+			if (++busy >= N2RNG_BUSY_LIMIT)
+				return -EBUSY;
+			udelay(1);
+		} else
+			return -ENODEV;
+	}
+}
+
+/* Just try to see if we can successfully access the control register
+ * of the RNG on the domain on which we are currently executing.
+ */
+static int n2rng_try_read_ctl(struct n2rng *np)
+{
+	unsigned long hv_err;
+	unsigned long x;
+
+	if (np->hvapi_major == 1) {
+		hv_err = sun4v_rng_get_diag_ctl();
+	} else {
+		/* We purposefully give invalid arguments, HV_NOACCESS
+		 * is higher priority than the errors we'd get from
+		 * these other cases, and that's the error we are
+		 * truly interested in.
+		 */
+		hv_err = sun4v_rng_ctl_read_v2(0UL, ~0UL, &x, &x, &x, &x);
+		switch (hv_err) {
+		case HV_EWOULDBLOCK:
+		case HV_ENOACCESS:
+			break;
+		default:
+			hv_err = HV_EOK;
+			break;
+		}
+	}
+
+	return n2rng_hv_err_trans(hv_err);
+}
+
+#define CONTROL_DEFAULT_BASE		\
+	((2 << RNG_CTL_ASEL_SHIFT) |	\
+	 (N2RNG_ACCUM_CYCLES_DEFAULT << RNG_CTL_WAIT_SHIFT) |	\
+	 RNG_CTL_LFSR)
+
+#define CONTROL_DEFAULT_0		\
+	(CONTROL_DEFAULT_BASE |		\
+	 (1 << RNG_CTL_VCO_SHIFT) |	\
+	 RNG_CTL_ES1)
+#define CONTROL_DEFAULT_1		\
+	(CONTROL_DEFAULT_BASE |		\
+	 (2 << RNG_CTL_VCO_SHIFT) |	\
+	 RNG_CTL_ES2)
+#define CONTROL_DEFAULT_2		\
+	(CONTROL_DEFAULT_BASE |		\
+	 (3 << RNG_CTL_VCO_SHIFT) |	\
+	 RNG_CTL_ES3)
+#define CONTROL_DEFAULT_3		\
+	(CONTROL_DEFAULT_BASE |		\
+	 RNG_CTL_ES1 | RNG_CTL_ES2 | RNG_CTL_ES3)
+
+static void n2rng_control_swstate_init(struct n2rng *np)
+{
+	int i;
+
+	np->flags |= N2RNG_FLAG_CONTROL;
+
+	np->health_check_sec = N2RNG_HEALTH_CHECK_SEC_DEFAULT;
+	np->accum_cycles = N2RNG_ACCUM_CYCLES_DEFAULT;
+	np->wd_timeo = N2RNG_WD_TIMEO_DEFAULT;
+
+	for (i = 0; i < np->num_units; i++) {
+		struct n2rng_unit *up = &np->units[i];
+
+		up->control[0] = CONTROL_DEFAULT_0;
+		up->control[1] = CONTROL_DEFAULT_1;
+		up->control[2] = CONTROL_DEFAULT_2;
+		up->control[3] = CONTROL_DEFAULT_3;
+	}
+
+	np->hv_state = HV_RNG_STATE_UNCONFIGURED;
+}
+
+static int n2rng_grab_diag_control(struct n2rng *np)
+{
+	int i, busy_count, err = -ENODEV;
+
+	busy_count = 0;
+	for (i = 0; i < 100; i++) {
+		err = n2rng_try_read_ctl(np);
+		if (err != -EAGAIN)
+			break;
+
+		if (++busy_count > 100) {
+			dev_err(&np->op->dev,
+				"Grab diag control timeout.\n");
+			return -ENODEV;
+		}
+
+		udelay(1);
+	}
+
+	return err;
+}
+
+static int n2rng_init_control(struct n2rng *np)
+{
+	int err = n2rng_grab_diag_control(np);
+
+	/* Not in the control domain, that's OK we are only a consumer
+	 * of the RNG data, we don't setup and program it.
+	 */
+	if (err == -EPERM)
+		return 0;
+	if (err)
+		return err;
+
+	n2rng_control_swstate_init(np);
+
+	return 0;
+}
+
+static int n2rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct n2rng *np = (struct n2rng *) rng->priv;
+	unsigned long ra = __pa(&np->test_data);
+	int len;
+
+	if (!(np->flags & N2RNG_FLAG_READY)) {
+		len = 0;
+	} else if (np->flags & N2RNG_FLAG_BUFFER_VALID) {
+		np->flags &= ~N2RNG_FLAG_BUFFER_VALID;
+		*data = np->buffer;
+		len = 4;
+	} else {
+		int err = n2rng_generic_read_data(ra);
+		if (!err) {
+			np->buffer = np->test_data >> 32;
+			*data = np->test_data & 0xffffffff;
+			len = 4;
+		} else {
+			dev_err(&np->op->dev, "RNG error, restesting\n");
+			np->flags &= ~N2RNG_FLAG_READY;
+			if (!(np->flags & N2RNG_FLAG_SHUTDOWN))
+				schedule_delayed_work(&np->work, 0);
+			len = 0;
+		}
+	}
+
+	return len;
+}
+
+/* On a guest node, just make sure we can read random data properly.
+ * If a control node reboots or reloads it's n2rng driver, this won't
+ * work during that time.  So we have to keep probing until the device
+ * becomes usable.
+ */
+static int n2rng_guest_check(struct n2rng *np)
+{
+	unsigned long ra = __pa(&np->test_data);
+
+	return n2rng_generic_read_data(ra);
+}
+
+static int n2rng_entropy_diag_read(struct n2rng *np, unsigned long unit,
+				   u64 *pre_control, u64 pre_state,
+				   u64 *buffer, unsigned long buf_len,
+				   u64 *post_control, u64 post_state)
+{
+	unsigned long post_ctl_ra = __pa(post_control);
+	unsigned long pre_ctl_ra = __pa(pre_control);
+	unsigned long buffer_ra = __pa(buffer);
+	int err;
+
+	err = n2rng_generic_write_control(np, pre_ctl_ra, unit, pre_state);
+	if (err)
+		return err;
+
+	err = n2rng_generic_read_diag_data(np, unit,
+					   buffer_ra, buf_len);
+
+	(void) n2rng_generic_write_control(np, post_ctl_ra, unit,
+					   post_state);
+
+	return err;
+}
+
+static u64 advance_polynomial(u64 poly, u64 val, int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		int highbit_set = ((s64)val < 0);
+
+		val <<= 1;
+		if (highbit_set)
+			val ^= poly;
+	}
+
+	return val;
+}
+
+static int n2rng_test_buffer_find(struct n2rng *np, u64 val)
+{
+	int i, count = 0;
+
+	/* Purposefully skip over the first word.  */
+	for (i = 1; i < SELFTEST_BUFFER_WORDS; i++) {
+		if (np->test_buffer[i] == val)
+			count++;
+	}
+	return count;
+}
+
+static void n2rng_dump_test_buffer(struct n2rng *np)
+{
+	int i;
+
+	for (i = 0; i < SELFTEST_BUFFER_WORDS; i++)
+		dev_err(&np->op->dev, "Test buffer slot %d [0x%016llx]\n",
+			i, np->test_buffer[i]);
+}
+
+static int n2rng_check_selftest_buffer(struct n2rng *np, unsigned long unit)
+{
+	u64 val = SELFTEST_VAL;
+	int err, matches, limit;
+
+	matches = 0;
+	for (limit = 0; limit < SELFTEST_LOOPS_MAX; limit++) {
+		matches += n2rng_test_buffer_find(np, val);
+		if (matches >= SELFTEST_MATCH_GOAL)
+			break;
+		val = advance_polynomial(SELFTEST_POLY, val, 1);
+	}
+
+	err = 0;
+	if (limit >= SELFTEST_LOOPS_MAX) {
+		err = -ENODEV;
+		dev_err(&np->op->dev, "Selftest failed on unit %lu\n", unit);
+		n2rng_dump_test_buffer(np);
+	} else
+		dev_info(&np->op->dev, "Selftest passed on unit %lu\n", unit);
+
+	return err;
+}
+
+static int n2rng_control_selftest(struct n2rng *np, unsigned long unit)
+{
+	int err;
+
+	np->test_control[0] = (0x2 << RNG_CTL_ASEL_SHIFT);
+	np->test_control[1] = (0x2 << RNG_CTL_ASEL_SHIFT);
+	np->test_control[2] = (0x2 << RNG_CTL_ASEL_SHIFT);
+	np->test_control[3] = ((0x2 << RNG_CTL_ASEL_SHIFT) |
+			       RNG_CTL_LFSR |
+			       ((SELFTEST_TICKS - 2) << RNG_CTL_WAIT_SHIFT));
+
+
+	err = n2rng_entropy_diag_read(np, unit, np->test_control,
+				      HV_RNG_STATE_HEALTHCHECK,
+				      np->test_buffer,
+				      sizeof(np->test_buffer),
+				      &np->units[unit].control[0],
+				      np->hv_state);
+	if (err)
+		return err;
+
+	return n2rng_check_selftest_buffer(np, unit);
+}
+
+static int n2rng_control_check(struct n2rng *np)
+{
+	int i;
+
+	for (i = 0; i < np->num_units; i++) {
+		int err = n2rng_control_selftest(np, i);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+/* The sanity checks passed, install the final configuration into the
+ * chip, it's ready to use.
+ */
+static int n2rng_control_configure_units(struct n2rng *np)
+{
+	int unit, err;
+
+	err = 0;
+	for (unit = 0; unit < np->num_units; unit++) {
+		struct n2rng_unit *up = &np->units[unit];
+		unsigned long ctl_ra = __pa(&up->control[0]);
+		int esrc;
+		u64 base;
+
+		base = ((np->accum_cycles << RNG_CTL_WAIT_SHIFT) |
+			(2 << RNG_CTL_ASEL_SHIFT) |
+			RNG_CTL_LFSR);
+
+		/* XXX This isn't the best.  We should fetch a bunch
+		 * XXX of words using each entropy source combined XXX
+		 * with each VCO setting, and see which combinations
+		 * XXX give the best random data.
+		 */
+		for (esrc = 0; esrc < 3; esrc++)
+			up->control[esrc] = base |
+				(esrc << RNG_CTL_VCO_SHIFT) |
+				(RNG_CTL_ES1 << esrc);
+
+		up->control[3] = base |
+			(RNG_CTL_ES1 | RNG_CTL_ES2 | RNG_CTL_ES3);
+
+		err = n2rng_generic_write_control(np, ctl_ra, unit,
+						  HV_RNG_STATE_CONFIGURED);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+static void n2rng_work(struct work_struct *work)
+{
+	struct n2rng *np = container_of(work, struct n2rng, work.work);
+	int err = 0;
+
+	if (!(np->flags & N2RNG_FLAG_CONTROL)) {
+		err = n2rng_guest_check(np);
+	} else {
+		preempt_disable();
+		err = n2rng_control_check(np);
+		preempt_enable();
+
+		if (!err)
+			err = n2rng_control_configure_units(np);
+	}
+
+	if (!err) {
+		np->flags |= N2RNG_FLAG_READY;
+		dev_info(&np->op->dev, "RNG ready\n");
+	}
+
+	if (err && !(np->flags & N2RNG_FLAG_SHUTDOWN))
+		schedule_delayed_work(&np->work, HZ * 2);
+}
+
+static void n2rng_driver_version(void)
+{
+	static int n2rng_version_printed;
+
+	if (n2rng_version_printed++ == 0)
+		pr_info("%s", version);
+}
+
+static const struct of_device_id n2rng_match[];
+static int n2rng_probe(struct platform_device *op)
+{
+	const struct of_device_id *match;
+	int multi_capable;
+	int err = -ENOMEM;
+	struct n2rng *np;
+
+	match = of_match_device(n2rng_match, &op->dev);
+	if (!match)
+		return -EINVAL;
+	multi_capable = (match->data != NULL);
+
+	n2rng_driver_version();
+	np = devm_kzalloc(&op->dev, sizeof(*np), GFP_KERNEL);
+	if (!np)
+		goto out;
+	np->op = op;
+
+	INIT_DELAYED_WORK(&np->work, n2rng_work);
+
+	if (multi_capable)
+		np->flags |= N2RNG_FLAG_MULTI;
+
+	err = -ENODEV;
+	np->hvapi_major = 2;
+	if (sun4v_hvapi_register(HV_GRP_RNG,
+				 np->hvapi_major,
+				 &np->hvapi_minor)) {
+		np->hvapi_major = 1;
+		if (sun4v_hvapi_register(HV_GRP_RNG,
+					 np->hvapi_major,
+					 &np->hvapi_minor)) {
+			dev_err(&op->dev, "Cannot register suitable "
+				"HVAPI version.\n");
+			goto out;
+		}
+	}
+
+	if (np->flags & N2RNG_FLAG_MULTI) {
+		if (np->hvapi_major < 2) {
+			dev_err(&op->dev, "multi-unit-capable RNG requires "
+				"HVAPI major version 2 or later, got %lu\n",
+				np->hvapi_major);
+			goto out_hvapi_unregister;
+		}
+		np->num_units = of_getintprop_default(op->dev.of_node,
+						      "rng-#units", 0);
+		if (!np->num_units) {
+			dev_err(&op->dev, "VF RNG lacks rng-#units property\n");
+			goto out_hvapi_unregister;
+		}
+	} else
+		np->num_units = 1;
+
+	dev_info(&op->dev, "Registered RNG HVAPI major %lu minor %lu\n",
+		 np->hvapi_major, np->hvapi_minor);
+
+	np->units = devm_kzalloc(&op->dev,
+				 sizeof(struct n2rng_unit) * np->num_units,
+				 GFP_KERNEL);
+	err = -ENOMEM;
+	if (!np->units)
+		goto out_hvapi_unregister;
+
+	err = n2rng_init_control(np);
+	if (err)
+		goto out_hvapi_unregister;
+
+	dev_info(&op->dev, "Found %s RNG, units: %d\n",
+		 ((np->flags & N2RNG_FLAG_MULTI) ?
+		  "multi-unit-capable" : "single-unit"),
+		 np->num_units);
+
+	np->hwrng.name = "n2rng";
+	np->hwrng.data_read = n2rng_data_read;
+	np->hwrng.priv = (unsigned long) np;
+
+	err = hwrng_register(&np->hwrng);
+	if (err)
+		goto out_hvapi_unregister;
+
+	platform_set_drvdata(op, np);
+
+	schedule_delayed_work(&np->work, 0);
+
+	return 0;
+
+out_hvapi_unregister:
+	sun4v_hvapi_unregister(HV_GRP_RNG);
+
+out:
+	return err;
+}
+
+static int n2rng_remove(struct platform_device *op)
+{
+	struct n2rng *np = platform_get_drvdata(op);
+
+	np->flags |= N2RNG_FLAG_SHUTDOWN;
+
+	cancel_delayed_work_sync(&np->work);
+
+	hwrng_unregister(&np->hwrng);
+
+	sun4v_hvapi_unregister(HV_GRP_RNG);
+
+	return 0;
+}
+
+static const struct of_device_id n2rng_match[] = {
+	{
+		.name		= "random-number-generator",
+		.compatible	= "SUNW,n2-rng",
+	},
+	{
+		.name		= "random-number-generator",
+		.compatible	= "SUNW,vf-rng",
+		.data		= (void *) 1,
+	},
+	{
+		.name		= "random-number-generator",
+		.compatible	= "SUNW,kt-rng",
+		.data		= (void *) 1,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, n2rng_match);
+
+static struct platform_driver n2rng_driver = {
+	.driver = {
+		.name = "n2rng",
+		.owner = THIS_MODULE,
+		.of_match_table = n2rng_match,
+	},
+	.probe		= n2rng_probe,
+	.remove		= n2rng_remove,
+};
+
+module_platform_driver(n2rng_driver);

drivers/char/hw_random/n2rng.h

@@ -0,0 +1,118 @@
+/* n2rng.h: Niagara2 RNG defines.
+ *
+ * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
+ */
+
+#ifndef _N2RNG_H
+#define _N2RNG_H
+
+#define RNG_CTL_WAIT       0x0000000001fffe00ULL /* Minimum wait time       */
+#define RNG_CTL_WAIT_SHIFT 9
+#define RNG_CTL_BYPASS     0x0000000000000100ULL /* VCO voltage source      */
+#define RNG_CTL_VCO        0x00000000000000c0ULL /* VCO rate control        */
+#define RNG_CTL_VCO_SHIFT  6
+#define RNG_CTL_ASEL       0x0000000000000030ULL /* Analog MUX select       */
+#define RNG_CTL_ASEL_SHIFT 4
+#define RNG_CTL_LFSR       0x0000000000000008ULL /* Use LFSR or plain shift */
+#define RNG_CTL_ES3        0x0000000000000004ULL /* Enable entropy source 3 */
+#define RNG_CTL_ES2        0x0000000000000002ULL /* Enable entropy source 2 */
+#define RNG_CTL_ES1        0x0000000000000001ULL /* Enable entropy source 1 */
+
+#define HV_FAST_RNG_GET_DIAG_CTL	0x130
+#define HV_FAST_RNG_CTL_READ		0x131
+#define HV_FAST_RNG_CTL_WRITE		0x132
+#define HV_FAST_RNG_DATA_READ_DIAG	0x133
+#define HV_FAST_RNG_DATA_READ		0x134
+
+#define HV_RNG_STATE_UNCONFIGURED	0
+#define HV_RNG_STATE_CONFIGURED		1
+#define HV_RNG_STATE_HEALTHCHECK	2
+#define HV_RNG_STATE_ERROR		3
+
+#define HV_RNG_NUM_CONTROL		4
+
+#ifndef __ASSEMBLY__
+extern unsigned long sun4v_rng_get_diag_ctl(void);
+extern unsigned long sun4v_rng_ctl_read_v1(unsigned long ctl_regs_ra,
+					   unsigned long *state,
+					   unsigned long *tick_delta);
+extern unsigned long sun4v_rng_ctl_read_v2(unsigned long ctl_regs_ra,
+					   unsigned long unit,
+					   unsigned long *state,
+					   unsigned long *tick_delta,
+					   unsigned long *watchdog,
+					   unsigned long *write_status);
+extern unsigned long sun4v_rng_ctl_write_v1(unsigned long ctl_regs_ra,
+					    unsigned long state,
+					    unsigned long write_timeout,
+					    unsigned long *tick_delta);
+extern unsigned long sun4v_rng_ctl_write_v2(unsigned long ctl_regs_ra,
+					    unsigned long state,
+					    unsigned long write_timeout,
+					    unsigned long unit);
+extern unsigned long sun4v_rng_data_read_diag_v1(unsigned long data_ra,
+						 unsigned long len,
+						 unsigned long *tick_delta);
+extern unsigned long sun4v_rng_data_read_diag_v2(unsigned long data_ra,
+						 unsigned long len,
+						 unsigned long unit,
+						 unsigned long *tick_delta);
+extern unsigned long sun4v_rng_data_read(unsigned long data_ra,
+					 unsigned long *tick_delta);
+
+struct n2rng_unit {
+	u64			control[HV_RNG_NUM_CONTROL];
+};
+
+struct n2rng {
+	struct platform_device	*op;
+
+	unsigned long		flags;
+#define N2RNG_FLAG_MULTI	0x00000001 /* Multi-unit capable RNG */
+#define N2RNG_FLAG_CONTROL	0x00000002 /* Operating in control domain */
+#define N2RNG_FLAG_READY	0x00000008 /* Ready for hw-rng layer      */
+#define N2RNG_FLAG_SHUTDOWN	0x00000010 /* Driver unregistering        */
+#define N2RNG_FLAG_BUFFER_VALID	0x00000020 /* u32 buffer holds valid data */
+
+	int			num_units;
+	struct n2rng_unit	*units;
+
+	struct hwrng		hwrng;
+	u32			buffer;
+
+	/* Registered hypervisor group API major and minor version.  */
+	unsigned long		hvapi_major;
+	unsigned long		hvapi_minor;
+
+	struct delayed_work	work;
+
+	unsigned long		hv_state; /* HV_RNG_STATE_foo */
+
+	unsigned long		health_check_sec;
+	unsigned long		accum_cycles;
+	unsigned long		wd_timeo;
+#define N2RNG_HEALTH_CHECK_SEC_DEFAULT	0
+#define N2RNG_ACCUM_CYCLES_DEFAULT	2048
+#define N2RNG_WD_TIMEO_DEFAULT		0
+
+	u64			scratch_control[HV_RNG_NUM_CONTROL];
+
+#define SELFTEST_TICKS		38859
+#define SELFTEST_VAL		((u64)0xB8820C7BD387E32C)
+#define SELFTEST_POLY		((u64)0x231DCEE91262B8A3)
+#define SELFTEST_MATCH_GOAL	6
+#define SELFTEST_LOOPS_MAX	40000
+#define SELFTEST_BUFFER_WORDS	8
+
+	u64			test_data;
+	u64			test_control[HV_RNG_NUM_CONTROL];
+	u64			test_buffer[SELFTEST_BUFFER_WORDS];
+};
+
+#define N2RNG_BLOCK_LIMIT	60000
+#define N2RNG_BUSY_LIMIT	100
+#define N2RNG_HCHECK_LIMIT	100
+
+#endif /* !(__ASSEMBLY__) */
+
+#endif /* _N2RNG_H */

drivers/char/hw_random/nomadik-rng.c

@@ -0,0 +1,106 @@
+/*
+ * Nomadik RNG support
+ *  Copyright 2009 Alessandro Rubini
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/amba/bus.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+static struct clk *rng_clk;
+
+static int nmk_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	void __iomem *base = (void __iomem *)rng->priv;
+
+	/*
+	 * The register is 32 bits and gives 16 random bits (low half).
+	 * A subsequent read will delay the core for 400ns, so we just read
+	 * once and accept the very unlikely very small delay, even if wait==0.
+	 */
+	*(u16 *)data = __raw_readl(base + 8) & 0xffff;
+	return 2;
+}
+
+/* we have at most one RNG per machine, granted */
+static struct hwrng nmk_rng = {
+	.name		= "nomadik",
+	.read		= nmk_rng_read,
+};
+
+static int nmk_rng_probe(struct amba_device *dev, const struct amba_id *id)
+{
+	void __iomem *base;
+	int ret;
+
+	rng_clk = devm_clk_get(&dev->dev, NULL);
+	if (IS_ERR(rng_clk)) {
+		dev_err(&dev->dev, "could not get rng clock\n");
+		ret = PTR_ERR(rng_clk);
+		return ret;
+	}
+
+	clk_prepare_enable(rng_clk);
+
+	ret = amba_request_regions(dev, dev->dev.init_name);
+	if (ret)
+		goto out_clk;
+	ret = -ENOMEM;
+	base = devm_ioremap(&dev->dev, dev->res.start,
+			    resource_size(&dev->res));
+	if (!base)
+		goto out_release;
+	nmk_rng.priv = (unsigned long)base;
+	ret = hwrng_register(&nmk_rng);
+	if (ret)
+		goto out_release;
+	return 0;
+
+out_release:
+	amba_release_regions(dev);
+out_clk:
+	clk_disable(rng_clk);
+	return ret;
+}
+
+static int nmk_rng_remove(struct amba_device *dev)
+{
+	hwrng_unregister(&nmk_rng);
+	amba_release_regions(dev);
+	clk_disable(rng_clk);
+	return 0;
+}
+
+static struct amba_id nmk_rng_ids[] = {
+	{
+		.id	= 0x000805e1,
+		.mask	= 0x000fffff, /* top bits are rev and cfg: accept all */
+	},
+	{0, 0},
+};
+
+MODULE_DEVICE_TABLE(amba, nmk_rng_ids);
+
+static struct amba_driver nmk_rng_driver = {
+	.drv = {
+		.owner = THIS_MODULE,
+		.name = "rng",
+		},
+	.probe = nmk_rng_probe,
+	.remove = nmk_rng_remove,
+	.id_table = nmk_rng_ids,
+};
+
+module_amba_driver(nmk_rng_driver);
+
+MODULE_LICENSE("GPL");

drivers/char/hw_random/octeon-rng.c

@@ -0,0 +1,129 @@
+/*
+ * Hardware Random Number Generator support for Cavium Networks
+ * Octeon processor family.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Cavium Networks
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/gfp.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-rnm-defs.h>
+
+struct octeon_rng {
+	struct hwrng ops;
+	void __iomem *control_status;
+	void __iomem *result;
+};
+
+static int octeon_rng_init(struct hwrng *rng)
+{
+	union cvmx_rnm_ctl_status ctl;
+	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+	ctl.u64 = 0;
+	ctl.s.ent_en = 1; /* Enable the entropy source.  */
+	ctl.s.rng_en = 1; /* Enable the RNG hardware.  */
+	cvmx_write_csr((u64)p->control_status, ctl.u64);
+	return 0;
+}
+
+static void octeon_rng_cleanup(struct hwrng *rng)
+{
+	union cvmx_rnm_ctl_status ctl;
+	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+	ctl.u64 = 0;
+	/* Disable everything.  */
+	cvmx_write_csr((u64)p->control_status, ctl.u64);
+}
+
+static int octeon_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
+
+	*data = cvmx_read64_uint32((u64)p->result);
+	return sizeof(u32);
+}
+
+static int octeon_rng_probe(struct platform_device *pdev)
+{
+	struct resource *res_ports;
+	struct resource *res_result;
+	struct octeon_rng *rng;
+	int ret;
+	struct hwrng ops = {
+		.name = "octeon",
+		.init = octeon_rng_init,
+		.cleanup = octeon_rng_cleanup,
+		.data_read = octeon_rng_data_read
+	};
+
+	rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+	if (!rng)
+		return -ENOMEM;
+
+	res_ports = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res_ports)
+		return -ENOENT;
+
+	res_result = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res_result)
+		return -ENOENT;
+
+
+	rng->control_status = devm_ioremap_nocache(&pdev->dev,
+						   res_ports->start,
+						   sizeof(u64));
+	if (!rng->control_status)
+		return -ENOENT;
+
+	rng->result = devm_ioremap_nocache(&pdev->dev,
+					   res_result->start,
+					   sizeof(u64));
+	if (!rng->result)
+		return -ENOENT;
+
+	rng->ops = ops;
+
+	platform_set_drvdata(pdev, &rng->ops);
+	ret = hwrng_register(&rng->ops);
+	if (ret)
+		return -ENOENT;
+
+	dev_info(&pdev->dev, "Octeon Random Number Generator\n");
+
+	return 0;
+}
+
+static int __exit octeon_rng_remove(struct platform_device *pdev)
+{
+	struct hwrng *rng = platform_get_drvdata(pdev);
+
+	hwrng_unregister(rng);
+
+	return 0;
+}
+
+static struct platform_driver octeon_rng_driver = {
+	.driver = {
+		.name		= "octeon_rng",
+		.owner		= THIS_MODULE,
+	},
+	.probe		= octeon_rng_probe,
+	.remove		= __exit_p(octeon_rng_remove),
+};
+
+module_platform_driver(octeon_rng_driver);
+
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/omap-rng.c

@@ -0,0 +1,470 @@
+/*
+ * omap-rng.c - RNG driver for TI OMAP CPU family
+ *
+ * Author: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * Mostly based on original driver:
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Juha Yrjölä <juha.yrjola@nokia.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/random.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/interrupt.h>
+
+#include <asm/io.h>
+
+#define RNG_REG_STATUS_RDY			(1 << 0)
+
+#define RNG_REG_INTACK_RDY_MASK			(1 << 0)
+#define RNG_REG_INTACK_SHUTDOWN_OFLO_MASK	(1 << 1)
+#define RNG_SHUTDOWN_OFLO_MASK			(1 << 1)
+
+#define RNG_CONTROL_STARTUP_CYCLES_SHIFT	16
+#define RNG_CONTROL_STARTUP_CYCLES_MASK		(0xffff << 16)
+#define RNG_CONTROL_ENABLE_TRNG_SHIFT		10
+#define RNG_CONTROL_ENABLE_TRNG_MASK		(1 << 10)
+
+#define RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT	16
+#define RNG_CONFIG_MAX_REFIL_CYCLES_MASK	(0xffff << 16)
+#define RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT	0
+#define RNG_CONFIG_MIN_REFIL_CYCLES_MASK	(0xff << 0)
+
+#define RNG_CONTROL_STARTUP_CYCLES		0xff
+#define RNG_CONFIG_MIN_REFIL_CYCLES		0x21
+#define RNG_CONFIG_MAX_REFIL_CYCLES		0x22
+
+#define RNG_ALARMCNT_ALARM_TH_SHIFT		0x0
+#define RNG_ALARMCNT_ALARM_TH_MASK		(0xff << 0)
+#define RNG_ALARMCNT_SHUTDOWN_TH_SHIFT		16
+#define RNG_ALARMCNT_SHUTDOWN_TH_MASK		(0x1f << 16)
+#define RNG_ALARM_THRESHOLD			0xff
+#define RNG_SHUTDOWN_THRESHOLD			0x4
+
+#define RNG_REG_FROENABLE_MASK			0xffffff
+#define RNG_REG_FRODETUNE_MASK			0xffffff
+
+#define OMAP2_RNG_OUTPUT_SIZE			0x4
+#define OMAP4_RNG_OUTPUT_SIZE			0x8
+
+enum {
+	RNG_OUTPUT_L_REG = 0,
+	RNG_OUTPUT_H_REG,
+	RNG_STATUS_REG,
+	RNG_INTMASK_REG,
+	RNG_INTACK_REG,
+	RNG_CONTROL_REG,
+	RNG_CONFIG_REG,
+	RNG_ALARMCNT_REG,
+	RNG_FROENABLE_REG,
+	RNG_FRODETUNE_REG,
+	RNG_ALARMMASK_REG,
+	RNG_ALARMSTOP_REG,
+	RNG_REV_REG,
+	RNG_SYSCONFIG_REG,
+};
+
+static const u16 reg_map_omap2[] = {
+	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_STATUS_REG]	= 0x4,
+	[RNG_CONFIG_REG]	= 0x28,
+	[RNG_REV_REG]		= 0x3c,
+	[RNG_SYSCONFIG_REG]	= 0x40,
+};
+
+static const u16 reg_map_omap4[] = {
+	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_OUTPUT_H_REG]	= 0x4,
+	[RNG_STATUS_REG]	= 0x8,
+	[RNG_INTMASK_REG]	= 0xc,
+	[RNG_INTACK_REG]	= 0x10,
+	[RNG_CONTROL_REG]	= 0x14,
+	[RNG_CONFIG_REG]	= 0x18,
+	[RNG_ALARMCNT_REG]	= 0x1c,
+	[RNG_FROENABLE_REG]	= 0x20,
+	[RNG_FRODETUNE_REG]	= 0x24,
+	[RNG_ALARMMASK_REG]	= 0x28,
+	[RNG_ALARMSTOP_REG]	= 0x2c,
+	[RNG_REV_REG]		= 0x1FE0,
+	[RNG_SYSCONFIG_REG]	= 0x1FE4,
+};
+
+struct omap_rng_dev;
+/**
+ * struct omap_rng_pdata - RNG IP block-specific data
+ * @regs: Pointer to the register offsets structure.
+ * @data_size: No. of bytes in RNG output.
+ * @data_present: Callback to determine if data is available.
+ * @init: Callback for IP specific initialization sequence.
+ * @cleanup: Callback for IP specific cleanup sequence.
+ */
+struct omap_rng_pdata {
+	u16	*regs;
+	u32	data_size;
+	u32	(*data_present)(struct omap_rng_dev *priv);
+	int	(*init)(struct omap_rng_dev *priv);
+	void	(*cleanup)(struct omap_rng_dev *priv);
+};
+
+struct omap_rng_dev {
+	void __iomem			*base;
+	struct device			*dev;
+	const struct omap_rng_pdata	*pdata;
+};
+
+static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
+{
+	return __raw_readl(priv->base + priv->pdata->regs[reg]);
+}
+
+static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg,
+				      u32 val)
+{
+	__raw_writel(val, priv->base + priv->pdata->regs[reg]);
+}
+
+static int omap_rng_data_present(struct hwrng *rng, int wait)
+{
+	struct omap_rng_dev *priv;
+	int data, i;
+
+	priv = (struct omap_rng_dev *)rng->priv;
+
+	for (i = 0; i < 20; i++) {
+		data = priv->pdata->data_present(priv);
+		if (data || !wait)
+			break;
+		/* RNG produces data fast enough (2+ MBit/sec, even
+		 * during "rngtest" loads, that these delays don't
+		 * seem to trigger.  We *could* use the RNG IRQ, but
+		 * that'd be higher overhead ... so why bother?
+		 */
+		udelay(10);
+	}
+	return data;
+}
+
+static int omap_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct omap_rng_dev *priv;
+	u32 data_size, i;
+
+	priv = (struct omap_rng_dev *)rng->priv;
+	data_size = priv->pdata->data_size;
+
+	for (i = 0; i < data_size / sizeof(u32); i++)
+		data[i] = omap_rng_read(priv, RNG_OUTPUT_L_REG + i);
+
+	if (priv->pdata->regs[RNG_INTACK_REG])
+		omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK);
+	return data_size;
+}
+
+static int omap_rng_init(struct hwrng *rng)
+{
+	struct omap_rng_dev *priv;
+
+	priv = (struct omap_rng_dev *)rng->priv;
+	return priv->pdata->init(priv);
+}
+
+static void omap_rng_cleanup(struct hwrng *rng)
+{
+	struct omap_rng_dev *priv;
+
+	priv = (struct omap_rng_dev *)rng->priv;
+	priv->pdata->cleanup(priv);
+}
+
+static struct hwrng omap_rng_ops = {
+	.name		= "omap",
+	.data_present	= omap_rng_data_present,
+	.data_read	= omap_rng_data_read,
+	.init		= omap_rng_init,
+	.cleanup	= omap_rng_cleanup,
+};
+
+static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv)
+{
+	return omap_rng_read(priv, RNG_STATUS_REG) ? 0 : 1;
+}
+
+static int omap2_rng_init(struct omap_rng_dev *priv)
+{
+	omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x1);
+	return 0;
+}
+
+static void omap2_rng_cleanup(struct omap_rng_dev *priv)
+{
+	omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x0);
+}
+
+static struct omap_rng_pdata omap2_rng_pdata = {
+	.regs		= (u16 *)reg_map_omap2,
+	.data_size	= OMAP2_RNG_OUTPUT_SIZE,
+	.data_present	= omap2_rng_data_present,
+	.init		= omap2_rng_init,
+	.cleanup	= omap2_rng_cleanup,
+};
+
+#if defined(CONFIG_OF)
+static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv)
+{
+	return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY;
+}
+
+static int omap4_rng_init(struct omap_rng_dev *priv)
+{
+	u32 val;
+
+	/* Return if RNG is already running. */
+	if (omap_rng_read(priv, RNG_CONFIG_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
+		return 0;
+
+	val = RNG_CONFIG_MIN_REFIL_CYCLES << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
+	val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+
+	omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
+	omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
+	val = RNG_ALARM_THRESHOLD << RNG_ALARMCNT_ALARM_TH_SHIFT;
+	val |= RNG_SHUTDOWN_THRESHOLD << RNG_ALARMCNT_SHUTDOWN_TH_SHIFT;
+	omap_rng_write(priv, RNG_ALARMCNT_REG, val);
+
+	val = RNG_CONTROL_STARTUP_CYCLES << RNG_CONTROL_STARTUP_CYCLES_SHIFT;
+	val |= RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONTROL_REG, val);
+
+	return 0;
+}
+
+static void omap4_rng_cleanup(struct omap_rng_dev *priv)
+{
+	int val;
+
+	val = omap_rng_read(priv, RNG_CONTROL_REG);
+	val &= ~RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+}
+
+static irqreturn_t omap4_rng_irq(int irq, void *dev_id)
+{
+	struct omap_rng_dev *priv = dev_id;
+	u32 fro_detune, fro_enable;
+
+	/*
+	 * Interrupt raised by a fro shutdown threshold, do the following:
+	 * 1. Clear the alarm events.
+	 * 2. De tune the FROs which are shutdown.
+	 * 3. Re enable the shutdown FROs.
+	 */
+	omap_rng_write(priv, RNG_ALARMMASK_REG, 0x0);
+	omap_rng_write(priv, RNG_ALARMSTOP_REG, 0x0);
+
+	fro_enable = omap_rng_read(priv, RNG_FROENABLE_REG);
+	fro_detune = ~fro_enable & RNG_REG_FRODETUNE_MASK;
+	fro_detune = fro_detune | omap_rng_read(priv, RNG_FRODETUNE_REG);
+	fro_enable = RNG_REG_FROENABLE_MASK;
+
+	omap_rng_write(priv, RNG_FRODETUNE_REG, fro_detune);
+	omap_rng_write(priv, RNG_FROENABLE_REG, fro_enable);
+
+	omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_SHUTDOWN_OFLO_MASK);
+
+	return IRQ_HANDLED;
+}
+
+static struct omap_rng_pdata omap4_rng_pdata = {
+	.regs		= (u16 *)reg_map_omap4,
+	.data_size	= OMAP4_RNG_OUTPUT_SIZE,
+	.data_present	= omap4_rng_data_present,
+	.init		= omap4_rng_init,
+	.cleanup	= omap4_rng_cleanup,
+};
+
+static const struct of_device_id omap_rng_of_match[] = {
+		{
+			.compatible	= "ti,omap2-rng",
+			.data		= &omap2_rng_pdata,
+		},
+		{
+			.compatible	= "ti,omap4-rng",
+			.data		= &omap4_rng_pdata,
+		},
+		{},
+};
+MODULE_DEVICE_TABLE(of, omap_rng_of_match);
+
+static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
+					  struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	int irq, err;
+
+	match = of_match_device(of_match_ptr(omap_rng_of_match), dev);
+	if (!match) {
+		dev_err(dev, "no compatible OF match\n");
+		return -EINVAL;
+	}
+	priv->pdata = match->data;
+
+	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng")) {
+		irq = platform_get_irq(pdev, 0);
+		if (irq < 0) {
+			dev_err(dev, "%s: error getting IRQ resource - %d\n",
+				__func__, irq);
+			return irq;
+		}
+
+		err = devm_request_irq(dev, irq, omap4_rng_irq,
+				       IRQF_TRIGGER_NONE, dev_name(dev), priv);
+		if (err) {
+			dev_err(dev, "unable to request irq %d, err = %d\n",
+				irq, err);
+			return err;
+		}
+		omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK);
+	}
+	return 0;
+}
+#else
+static int of_get_omap_rng_device_details(struct omap_rng_dev *omap_rng,
+					  struct platform_device *pdev)
+{
+	return -EINVAL;
+}
+#endif
+
+static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng)
+{
+	/* Only OMAP2/3 can be non-DT */
+	omap_rng->pdata = &omap2_rng_pdata;
+	return 0;
+}
+
+static int omap_rng_probe(struct platform_device *pdev)
+{
+	struct omap_rng_dev *priv;
+	struct resource *res;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(struct omap_rng_dev), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	omap_rng_ops.priv = (unsigned long)priv;
+	platform_set_drvdata(pdev, priv);
+	priv->dev = dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->base)) {
+		ret = PTR_ERR(priv->base);
+		goto err_ioremap;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) :
+				get_omap_rng_device_details(priv);
+	if (ret)
+		goto err_ioremap;
+
+	ret = hwrng_register(&omap_rng_ops);
+	if (ret)
+		goto err_register;
+
+	dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n",
+		 omap_rng_read(priv, RNG_REV_REG));
+
+	return 0;
+
+err_register:
+	priv->base = NULL;
+	pm_runtime_disable(&pdev->dev);
+err_ioremap:
+	dev_err(dev, "initialization failed.\n");
+	return ret;
+}
+
+static int __exit omap_rng_remove(struct platform_device *pdev)
+{
+	struct omap_rng_dev *priv = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&omap_rng_ops);
+
+	priv->pdata->cleanup(priv);
+
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int omap_rng_suspend(struct device *dev)
+{
+	struct omap_rng_dev *priv = dev_get_drvdata(dev);
+
+	priv->pdata->cleanup(priv);
+	pm_runtime_put_sync(dev);
+
+	return 0;
+}
+
+static int omap_rng_resume(struct device *dev)
+{
+	struct omap_rng_dev *priv = dev_get_drvdata(dev);
+
+	pm_runtime_get_sync(dev);
+	priv->pdata->init(priv);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(omap_rng_pm, omap_rng_suspend, omap_rng_resume);
+#define	OMAP_RNG_PM	(&omap_rng_pm)
+
+#else
+
+#define	OMAP_RNG_PM	NULL
+
+#endif
+
+static struct platform_driver omap_rng_driver = {
+	.driver = {
+		.name		= "omap_rng",
+		.owner		= THIS_MODULE,
+		.pm		= OMAP_RNG_PM,
+		.of_match_table = of_match_ptr(omap_rng_of_match),
+	},
+	.probe		= omap_rng_probe,
+	.remove		= __exit_p(omap_rng_remove),
+};
+
+module_platform_driver(omap_rng_driver);
+MODULE_ALIAS("platform:omap_rng");
+MODULE_AUTHOR("Deepak Saxena (and others)");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/omap3-rom-rng.c

@@ -0,0 +1,140 @@
+/*
+ * omap3-rom-rng.c - RNG driver for TI OMAP3 CPU family
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ * Author: Juha Yrjola <juha.yrjola@solidboot.com>
+ *
+ * Copyright (C) 2013 Pali Rohár <pali.rohar@gmail.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/random.h>
+#include <linux/hw_random.h>
+#include <linux/timer.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+
+#define RNG_RESET			0x01
+#define RNG_GEN_PRNG_HW_INIT		0x02
+#define RNG_GEN_HW			0x08
+
+/* param1: ptr, param2: count, param3: flag */
+static u32 (*omap3_rom_rng_call)(u32, u32, u32);
+
+static struct timer_list idle_timer;
+static int rng_idle;
+static struct clk *rng_clk;
+
+static void omap3_rom_rng_idle(unsigned long data)
+{
+	int r;
+
+	r = omap3_rom_rng_call(0, 0, RNG_RESET);
+	if (r != 0) {
+		pr_err("reset failed: %d\n", r);
+		return;
+	}
+	clk_disable_unprepare(rng_clk);
+	rng_idle = 1;
+}
+
+static int omap3_rom_rng_get_random(void *buf, unsigned int count)
+{
+	u32 r;
+	u32 ptr;
+
+	del_timer_sync(&idle_timer);
+	if (rng_idle) {
+		clk_prepare_enable(rng_clk);
+		r = omap3_rom_rng_call(0, 0, RNG_GEN_PRNG_HW_INIT);
+		if (r != 0) {
+			clk_disable_unprepare(rng_clk);
+			pr_err("HW init failed: %d\n", r);
+			return -EIO;
+		}
+		rng_idle = 0;
+	}
+
+	ptr = virt_to_phys(buf);
+	r = omap3_rom_rng_call(ptr, count, RNG_GEN_HW);
+	mod_timer(&idle_timer, jiffies + msecs_to_jiffies(500));
+	if (r != 0)
+		return -EINVAL;
+	return 0;
+}
+
+static int omap3_rom_rng_data_present(struct hwrng *rng, int wait)
+{
+	return 1;
+}
+
+static int omap3_rom_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	int r;
+
+	r = omap3_rom_rng_get_random(data, 4);
+	if (r < 0)
+		return r;
+	return 4;
+}
+
+static struct hwrng omap3_rom_rng_ops = {
+	.name		= "omap3-rom",
+	.data_present	= omap3_rom_rng_data_present,
+	.data_read	= omap3_rom_rng_data_read,
+};
+
+static int omap3_rom_rng_probe(struct platform_device *pdev)
+{
+	pr_info("initializing\n");
+
+	omap3_rom_rng_call = pdev->dev.platform_data;
+	if (!omap3_rom_rng_call) {
+		pr_err("omap3_rom_rng_call is NULL\n");
+		return -EINVAL;
+	}
+
+	setup_timer(&idle_timer, omap3_rom_rng_idle, 0);
+	rng_clk = devm_clk_get(&pdev->dev, "ick");
+	if (IS_ERR(rng_clk)) {
+		pr_err("unable to get RNG clock\n");
+		return PTR_ERR(rng_clk);
+	}
+
+	/* Leave the RNG in reset state. */
+	clk_prepare_enable(rng_clk);
+	omap3_rom_rng_idle(0);
+
+	return hwrng_register(&omap3_rom_rng_ops);
+}
+
+static int omap3_rom_rng_remove(struct platform_device *pdev)
+{
+	hwrng_unregister(&omap3_rom_rng_ops);
+	clk_disable_unprepare(rng_clk);
+	return 0;
+}
+
+static struct platform_driver omap3_rom_rng_driver = {
+	.driver = {
+		.name		= "omap3-rom-rng",
+		.owner		= THIS_MODULE,
+	},
+	.probe		= omap3_rom_rng_probe,
+	.remove		= omap3_rom_rng_remove,
+};
+
+module_platform_driver(omap3_rom_rng_driver);
+
+MODULE_ALIAS("platform:omap3-rom-rng");
+MODULE_AUTHOR("Juha Yrjola");
+MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/pasemi-rng.c

@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2006-2007 PA Semi, Inc
+ *
+ * Maintained by: Olof Johansson <olof@lixom.net>
+ *
+ * Driver for the PWRficient onchip rng
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <asm/io.h>
+
+#define SDCRNG_CTL_REG			0x00
+#define   SDCRNG_CTL_FVLD_M		0x0000f000
+#define   SDCRNG_CTL_FVLD_S		12
+#define   SDCRNG_CTL_KSZ		0x00000800
+#define   SDCRNG_CTL_RSRC_CRG		0x00000010
+#define   SDCRNG_CTL_RSRC_RRG		0x00000000
+#define   SDCRNG_CTL_CE			0x00000004
+#define   SDCRNG_CTL_RE			0x00000002
+#define   SDCRNG_CTL_DR			0x00000001
+#define   SDCRNG_CTL_SELECT_RRG_RNG	(SDCRNG_CTL_RE | SDCRNG_CTL_RSRC_RRG)
+#define   SDCRNG_CTL_SELECT_CRG_RNG	(SDCRNG_CTL_CE | SDCRNG_CTL_RSRC_CRG)
+#define SDCRNG_VAL_REG			0x20
+
+#define MODULE_NAME "pasemi_rng"
+
+static int pasemi_rng_data_present(struct hwrng *rng, int wait)
+{
+	void __iomem *rng_regs = (void __iomem *)rng->priv;
+	int data, i;
+
+	for (i = 0; i < 20; i++) {
+		data = (in_le32(rng_regs + SDCRNG_CTL_REG)
+			& SDCRNG_CTL_FVLD_M) ? 1 : 0;
+		if (data || !wait)
+			break;
+		udelay(10);
+	}
+	return data;
+}
+
+static int pasemi_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	void __iomem *rng_regs = (void __iomem *)rng->priv;
+	*data = in_le32(rng_regs + SDCRNG_VAL_REG);
+	return 4;
+}
+
+static int pasemi_rng_init(struct hwrng *rng)
+{
+	void __iomem *rng_regs = (void __iomem *)rng->priv;
+	u32 ctl;
+
+	ctl = SDCRNG_CTL_DR | SDCRNG_CTL_SELECT_RRG_RNG | SDCRNG_CTL_KSZ;
+	out_le32(rng_regs + SDCRNG_CTL_REG, ctl);
+	out_le32(rng_regs + SDCRNG_CTL_REG, ctl & ~SDCRNG_CTL_DR);
+
+	return 0;
+}
+
+static void pasemi_rng_cleanup(struct hwrng *rng)
+{
+	void __iomem *rng_regs = (void __iomem *)rng->priv;
+	u32 ctl;
+
+	ctl = SDCRNG_CTL_RE | SDCRNG_CTL_CE;
+	out_le32(rng_regs + SDCRNG_CTL_REG,
+		 in_le32(rng_regs + SDCRNG_CTL_REG) & ~ctl);
+}
+
+static struct hwrng pasemi_rng = {
+	.name		= MODULE_NAME,
+	.init		= pasemi_rng_init,
+	.cleanup	= pasemi_rng_cleanup,
+	.data_present	= pasemi_rng_data_present,
+	.data_read	= pasemi_rng_data_read,
+};
+
+static int rng_probe(struct platform_device *ofdev)
+{
+	void __iomem *rng_regs;
+	struct device_node *rng_np = ofdev->dev.of_node;
+	struct resource res;
+	int err = 0;
+
+	err = of_address_to_resource(rng_np, 0, &res);
+	if (err)
+		return -ENODEV;
+
+	rng_regs = ioremap(res.start, 0x100);
+
+	if (!rng_regs)
+		return -ENOMEM;
+
+	pasemi_rng.priv = (unsigned long)rng_regs;
+
+	pr_info("Registering PA Semi RNG\n");
+
+	err = hwrng_register(&pasemi_rng);
+
+	if (err)
+		iounmap(rng_regs);
+
+	return err;
+}
+
+static int rng_remove(struct platform_device *dev)
+{
+	void __iomem *rng_regs = (void __iomem *)pasemi_rng.priv;
+
+	hwrng_unregister(&pasemi_rng);
+	iounmap(rng_regs);
+
+	return 0;
+}
+
+static struct of_device_id rng_match[] = {
+	{ .compatible      = "1682m-rng", },
+	{ .compatible      = "pasemi,pwrficient-rng", },
+	{ },
+};
+
+static struct platform_driver rng_driver = {
+	.driver = {
+		.name = "pasemi-rng",
+		.owner = THIS_MODULE,
+		.of_match_table = rng_match,
+	},
+	.probe		= rng_probe,
+	.remove		= rng_remove,
+};
+
+module_platform_driver(rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
+MODULE_DESCRIPTION("H/W RNG driver for PA Semi processor");

drivers/char/hw_random/powernv-rng.c

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/hw_random.h>
+
+static int powernv_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	unsigned long *buf;
+	int i, len;
+
+	/* We rely on rng_buffer_size() being >= sizeof(unsigned long) */
+	len = max / sizeof(unsigned long);
+
+	buf = (unsigned long *)data;
+
+	for (i = 0; i < len; i++)
+		powernv_get_random_long(buf++);
+
+	return len * sizeof(unsigned long);
+}
+
+static struct hwrng powernv_hwrng = {
+	.name = "powernv-rng",
+	.read = powernv_rng_read,
+};
+
+static int powernv_rng_remove(struct platform_device *pdev)
+{
+	hwrng_unregister(&powernv_hwrng);
+
+	return 0;
+}
+
+static int powernv_rng_probe(struct platform_device *pdev)
+{
+	int rc;
+
+	rc = hwrng_register(&powernv_hwrng);
+	if (rc) {
+		/* We only register one device, ignore any others */
+		if (rc == -EEXIST)
+			rc = -ENODEV;
+
+		return rc;
+	}
+
+	pr_info("Registered powernv hwrng.\n");
+
+	return 0;
+}
+
+static struct of_device_id powernv_rng_match[] = {
+	{ .compatible	= "ibm,power-rng",},
+	{},
+};
+MODULE_DEVICE_TABLE(of, powernv_rng_match);
+
+static struct platform_driver powernv_rng_driver = {
+	.driver = {
+		.name = "powernv_rng",
+		.of_match_table = powernv_rng_match,
+	},
+	.probe	= powernv_rng_probe,
+	.remove = powernv_rng_remove,
+};
+module_platform_driver(powernv_rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above");

drivers/char/hw_random/ppc4xx-rng.c

@@ -0,0 +1,147 @@
+/*
+ * Generic PowerPC 44x RNG driver
+ *
+ * Copyright 2011 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <asm/io.h>
+
+#define PPC4XX_TRNG_DEV_CTRL 0x60080
+
+#define PPC4XX_TRNGE 0x00020000
+#define PPC4XX_TRNG_CTRL 0x0008
+#define PPC4XX_TRNG_CTRL_DALM 0x20
+#define PPC4XX_TRNG_STAT 0x0004
+#define PPC4XX_TRNG_STAT_B 0x1
+#define PPC4XX_TRNG_DATA 0x0000
+
+#define MODULE_NAME "ppc4xx_rng"
+
+static int ppc4xx_rng_data_present(struct hwrng *rng, int wait)
+{
+	void __iomem *rng_regs = (void __iomem *) rng->priv;
+	int busy, i, present = 0;
+
+	for (i = 0; i < 20; i++) {
+		busy = (in_le32(rng_regs + PPC4XX_TRNG_STAT) & PPC4XX_TRNG_STAT_B);
+		if (!busy || !wait) {
+			present = 1;
+			break;
+		}
+		udelay(10);
+	}
+	return present;
+}
+
+static int ppc4xx_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	void __iomem *rng_regs = (void __iomem *) rng->priv;
+	*data = in_le32(rng_regs + PPC4XX_TRNG_DATA);
+	return 4;
+}
+
+static int ppc4xx_rng_enable(int enable)
+{
+	struct device_node *ctrl;
+	void __iomem *ctrl_reg;
+	int err = 0;
+	u32 val;
+
+	/* Find the main crypto device node and map it to turn the TRNG on */
+	ctrl = of_find_compatible_node(NULL, NULL, "amcc,ppc4xx-crypto");
+	if (!ctrl)
+		return -ENODEV;
+
+	ctrl_reg = of_iomap(ctrl, 0);
+	if (!ctrl_reg) {
+		err = -ENODEV;
+		goto out;
+	}
+
+	val = in_le32(ctrl_reg + PPC4XX_TRNG_DEV_CTRL);
+
+	if (enable)
+		val |= PPC4XX_TRNGE;
+	else
+		val = val & ~PPC4XX_TRNGE;
+
+	out_le32(ctrl_reg + PPC4XX_TRNG_DEV_CTRL, val);
+	iounmap(ctrl_reg);
+
+out:
+	of_node_put(ctrl);
+
+	return err;
+}
+
+static struct hwrng ppc4xx_rng = {
+	.name = MODULE_NAME,
+	.data_present = ppc4xx_rng_data_present,
+	.data_read = ppc4xx_rng_data_read,
+};
+
+static int ppc4xx_rng_probe(struct platform_device *dev)
+{
+	void __iomem *rng_regs;
+	int err = 0;
+
+	rng_regs = of_iomap(dev->dev.of_node, 0);
+	if (!rng_regs)
+		return -ENODEV;
+
+	err = ppc4xx_rng_enable(1);
+	if (err)
+		return err;
+
+	out_le32(rng_regs + PPC4XX_TRNG_CTRL, PPC4XX_TRNG_CTRL_DALM);
+	ppc4xx_rng.priv = (unsigned long) rng_regs;
+
+	err = hwrng_register(&ppc4xx_rng);
+
+	return err;
+}
+
+static int ppc4xx_rng_remove(struct platform_device *dev)
+{
+	void __iomem *rng_regs = (void __iomem *) ppc4xx_rng.priv;
+
+	hwrng_unregister(&ppc4xx_rng);
+	ppc4xx_rng_enable(0);
+	iounmap(rng_regs);
+
+	return 0;
+}
+
+static struct of_device_id ppc4xx_rng_match[] = {
+	{ .compatible = "ppc4xx-rng", },
+	{ .compatible = "amcc,ppc460ex-rng", },
+	{ .compatible = "amcc,ppc440epx-rng", },
+	{},
+};
+
+static struct platform_driver ppc4xx_rng_driver = {
+	.driver = {
+		.name = MODULE_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table = ppc4xx_rng_match,
+	},
+	.probe = ppc4xx_rng_probe,
+	.remove = ppc4xx_rng_remove,
+};
+
+module_platform_driver(ppc4xx_rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Josh Boyer <jwboyer@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("HW RNG driver for PPC 4xx processors");

drivers/char/hw_random/pseries-rng.c

@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2010 Michael Neuling IBM Corporation
+ *
+ * Driver for the pseries hardware RNG for POWER7+ and above
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/hw_random.h>
+#include <asm/vio.h>
+
+
+static int pseries_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	u64 buffer[PLPAR_HCALL_BUFSIZE];
+	size_t size = max < 8 ? max : 8;
+	int rc;
+
+	rc = plpar_hcall(H_RANDOM, (unsigned long *)buffer);
+	if (rc != H_SUCCESS) {
+		pr_err_ratelimited("H_RANDOM call failed %d\n", rc);
+		return -EIO;
+	}
+	memcpy(data, buffer, size);
+
+	/* The hypervisor interface returns 64 bits */
+	return size;
+}
+
+/**
+ * pseries_rng_get_desired_dma - Return desired DMA allocate for CMO operations
+ *
+ * This is a required function for a driver to operate in a CMO environment
+ * but this device does not make use of DMA allocations, return 0.
+ *
+ * Return value:
+ *	Number of bytes of IO data the driver will need to perform well -> 0
+ */
+static unsigned long pseries_rng_get_desired_dma(struct vio_dev *vdev)
+{
+	return 0;
+};
+
+static struct hwrng pseries_rng = {
+	.name		= KBUILD_MODNAME,
+	.read		= pseries_rng_read,
+};
+
+static int __init pseries_rng_probe(struct vio_dev *dev,
+		const struct vio_device_id *id)
+{
+	return hwrng_register(&pseries_rng);
+}
+
+static int __exit pseries_rng_remove(struct vio_dev *dev)
+{
+	hwrng_unregister(&pseries_rng);
+	return 0;
+}
+
+static struct vio_device_id pseries_rng_driver_ids[] = {
+	{ "ibm,random-v1", "ibm,random"},
+	{ "", "" }
+};
+MODULE_DEVICE_TABLE(vio, pseries_rng_driver_ids);
+
+static struct vio_driver pseries_rng_driver = {
+	.name = KBUILD_MODNAME,
+	.probe = pseries_rng_probe,
+	.remove = pseries_rng_remove,
+	.get_desired_dma = pseries_rng_get_desired_dma,
+	.id_table = pseries_rng_driver_ids
+};
+
+static int __init rng_init(void)
+{
+	pr_info("Registering IBM pSeries RNG driver\n");
+	return vio_register_driver(&pseries_rng_driver);
+}
+
+module_init(rng_init);
+
+static void __exit rng_exit(void)
+{
+	vio_unregister_driver(&pseries_rng_driver);
+}
+module_exit(rng_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michael Neuling <mikey@neuling.org>");
+MODULE_DESCRIPTION("H/W RNG driver for IBM pSeries processors");

drivers/char/hw_random/timeriomem-rng.c

@@ -0,0 +1,214 @@
+/*
+ * drivers/char/hw_random/timeriomem-rng.c
+ *
+ * Copyright (C) 2009 Alexander Clouter <alex@digriz.org.uk>
+ *
+ * Derived from drivers/char/hw_random/omap-rng.c
+ *   Copyright 2005 (c) MontaVista Software, Inc.
+ *   Author: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Overview:
+ *   This driver is useful for platforms that have an IO range that provides
+ *   periodic random data from a single IO memory address.  All the platform
+ *   has to do is provide the address and 'wait time' that new data becomes
+ *   available.
+ *
+ * TODO: add support for reading sizes other than 32bits and masking
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/timeriomem-rng.h>
+#include <linux/jiffies.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/completion.h>
+
+struct timeriomem_rng_private_data {
+	void __iomem		*io_base;
+	unsigned int		expires;
+	unsigned int		period;
+	unsigned int		present:1;
+
+	struct timer_list	timer;
+	struct completion	completion;
+
+	struct hwrng		timeriomem_rng_ops;
+};
+
+#define to_rng_priv(rng) \
+		((struct timeriomem_rng_private_data *)rng->priv)
+
+/*
+ * have data return 1, however return 0 if we have nothing
+ */
+static int timeriomem_rng_data_present(struct hwrng *rng, int wait)
+{
+	struct timeriomem_rng_private_data *priv = to_rng_priv(rng);
+
+	if (!wait || priv->present)
+		return priv->present;
+
+	wait_for_completion(&priv->completion);
+
+	return 1;
+}
+
+static int timeriomem_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct timeriomem_rng_private_data *priv = to_rng_priv(rng);
+	unsigned long cur;
+	s32 delay;
+
+	*data = readl(priv->io_base);
+
+	cur = jiffies;
+
+	delay = cur - priv->expires;
+	delay = priv->period - (delay % priv->period);
+
+	priv->expires = cur + delay;
+	priv->present = 0;
+
+	reinit_completion(&priv->completion);
+	mod_timer(&priv->timer, priv->expires);
+
+	return 4;
+}
+
+static void timeriomem_rng_trigger(unsigned long data)
+{
+	struct timeriomem_rng_private_data *priv
+			= (struct timeriomem_rng_private_data *)data;
+
+	priv->present = 1;
+	complete(&priv->completion);
+}
+
+static int timeriomem_rng_probe(struct platform_device *pdev)
+{
+	struct timeriomem_rng_data *pdata = pdev->dev.platform_data;
+	struct timeriomem_rng_private_data *priv;
+	struct resource *res;
+	int err = 0;
+	int period;
+
+	if (!pdev->dev.of_node && !pdata) {
+		dev_err(&pdev->dev, "timeriomem_rng_data is missing\n");
+		return -EINVAL;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENXIO;
+
+	if (res->start % 4 != 0 || resource_size(res) != 4) {
+		dev_err(&pdev->dev,
+			"address must be four bytes wide and aligned\n");
+		return -EINVAL;
+	}
+
+	/* Allocate memory for the device structure (and zero it) */
+	priv = devm_kzalloc(&pdev->dev,
+			sizeof(struct timeriomem_rng_private_data), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, priv);
+
+	if (pdev->dev.of_node) {
+		int i;
+
+		if (!of_property_read_u32(pdev->dev.of_node,
+						"period", &i))
+			period = i;
+		else {
+			dev_err(&pdev->dev, "missing period\n");
+			return -EINVAL;
+		}
+	} else {
+		period = pdata->period;
+	}
+
+	priv->period = usecs_to_jiffies(period);
+	if (priv->period < 1) {
+		dev_err(&pdev->dev, "period is less than one jiffy\n");
+		return -EINVAL;
+	}
+
+	priv->expires	= jiffies;
+	priv->present	= 1;
+
+	init_completion(&priv->completion);
+	complete(&priv->completion);
+
+	setup_timer(&priv->timer, timeriomem_rng_trigger, (unsigned long)priv);
+
+	priv->timeriomem_rng_ops.name		= dev_name(&pdev->dev);
+	priv->timeriomem_rng_ops.data_present	= timeriomem_rng_data_present;
+	priv->timeriomem_rng_ops.data_read	= timeriomem_rng_data_read;
+	priv->timeriomem_rng_ops.priv		= (unsigned long)priv;
+
+	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->io_base)) {
+		err = PTR_ERR(priv->io_base);
+		goto out_timer;
+	}
+
+	err = hwrng_register(&priv->timeriomem_rng_ops);
+	if (err) {
+		dev_err(&pdev->dev, "problem registering\n");
+		goto out_timer;
+	}
+
+	dev_info(&pdev->dev, "32bits from 0x%p @ %dus\n",
+			priv->io_base, period);
+
+	return 0;
+
+out_timer:
+	del_timer_sync(&priv->timer);
+	return err;
+}
+
+static int timeriomem_rng_remove(struct platform_device *pdev)
+{
+	struct timeriomem_rng_private_data *priv = platform_get_drvdata(pdev);
+
+	hwrng_unregister(&priv->timeriomem_rng_ops);
+
+	del_timer_sync(&priv->timer);
+
+	return 0;
+}
+
+static const struct of_device_id timeriomem_rng_match[] = {
+	{ .compatible = "timeriomem_rng" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, timeriomem_rng_match);
+
+static struct platform_driver timeriomem_rng_driver = {
+	.driver = {
+		.name		= "timeriomem_rng",
+		.owner		= THIS_MODULE,
+		.of_match_table	= timeriomem_rng_match,
+	},
+	.probe		= timeriomem_rng_probe,
+	.remove		= timeriomem_rng_remove,
+};
+
+module_platform_driver(timeriomem_rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
+MODULE_DESCRIPTION("Timer IOMEM H/W RNG driver");

drivers/char/hw_random/tpm-rng.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2012 Kent Yoder IBM Corporation
+ *
+ * HWRNG interfaces to pull RNG data from a TPM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/hw_random.h>
+#include <linux/tpm.h>
+
+#define MODULE_NAME "tpm-rng"
+
+static int tpm_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	return tpm_get_random(TPM_ANY_NUM, data, max);
+}
+
+static struct hwrng tpm_rng = {
+	.name = MODULE_NAME,
+	.read = tpm_rng_read,
+};
+
+static int __init rng_init(void)
+{
+	return hwrng_register(&tpm_rng);
+}
+module_init(rng_init);
+
+static void __exit rng_exit(void)
+{
+	hwrng_unregister(&tpm_rng);
+}
+module_exit(rng_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Kent Yoder <key@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("RNG driver for TPM devices");

drivers/char/hw_random/tx4939-rng.c

@@ -0,0 +1,169 @@
+/*
+ * RNG driver for TX4939 Random Number Generators (RNG)
+ *
+ * Copyright (C) 2009 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/gfp.h>
+
+#define TX4939_RNG_RCSR		0x00000000
+#define TX4939_RNG_ROR(n)	(0x00000018 + (n) * 8)
+
+#define TX4939_RNG_RCSR_INTE	0x00000008
+#define TX4939_RNG_RCSR_RST	0x00000004
+#define TX4939_RNG_RCSR_FIN	0x00000002
+#define TX4939_RNG_RCSR_ST	0x00000001
+
+struct tx4939_rng {
+	struct hwrng rng;
+	void __iomem *base;
+	u64 databuf[3];
+	unsigned int data_avail;
+};
+
+static void rng_io_start(void)
+{
+#ifndef CONFIG_64BIT
+	/*
+	 * readq is reading a 64-bit register using a 64-bit load.  On
+	 * a 32-bit kernel however interrupts or any other processor
+	 * exception would clobber the upper 32-bit of the processor
+	 * register so interrupts need to be disabled.
+	 */
+	local_irq_disable();
+#endif
+}
+
+static void rng_io_end(void)
+{
+#ifndef CONFIG_64BIT
+	local_irq_enable();
+#endif
+}
+
+static u64 read_rng(void __iomem *base, unsigned int offset)
+{
+	return ____raw_readq(base + offset);
+}
+
+static void write_rng(u64 val, void __iomem *base, unsigned int offset)
+{
+	return ____raw_writeq(val, base + offset);
+}
+
+static int tx4939_rng_data_present(struct hwrng *rng, int wait)
+{
+	struct tx4939_rng *rngdev = container_of(rng, struct tx4939_rng, rng);
+	int i;
+
+	if (rngdev->data_avail)
+		return rngdev->data_avail;
+	for (i = 0; i < 20; i++) {
+		rng_io_start();
+		if (!(read_rng(rngdev->base, TX4939_RNG_RCSR)
+		      & TX4939_RNG_RCSR_ST)) {
+			rngdev->databuf[0] =
+				read_rng(rngdev->base, TX4939_RNG_ROR(0));
+			rngdev->databuf[1] =
+				read_rng(rngdev->base, TX4939_RNG_ROR(1));
+			rngdev->databuf[2] =
+				read_rng(rngdev->base, TX4939_RNG_ROR(2));
+			rngdev->data_avail =
+				sizeof(rngdev->databuf) / sizeof(u32);
+			/* Start RNG */
+			write_rng(TX4939_RNG_RCSR_ST,
+				  rngdev->base, TX4939_RNG_RCSR);
+			wait = 0;
+		}
+		rng_io_end();
+		if (!wait)
+			break;
+		/* 90 bus clock cycles by default for generation */
+		ndelay(90 * 5);
+	}
+	return rngdev->data_avail;
+}
+
+static int tx4939_rng_data_read(struct hwrng *rng, u32 *buffer)
+{
+	struct tx4939_rng *rngdev = container_of(rng, struct tx4939_rng, rng);
+
+	rngdev->data_avail--;
+	*buffer = *((u32 *)&rngdev->databuf + rngdev->data_avail);
+	return sizeof(u32);
+}
+
+static int __init tx4939_rng_probe(struct platform_device *dev)
+{
+	struct tx4939_rng *rngdev;
+	struct resource *r;
+	int i;
+
+	rngdev = devm_kzalloc(&dev->dev, sizeof(*rngdev), GFP_KERNEL);
+	if (!rngdev)
+		return -ENOMEM;
+	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	rngdev->base = devm_ioremap_resource(&dev->dev, r);
+	if (IS_ERR(rngdev->base))
+		return PTR_ERR(rngdev->base);
+
+	rngdev->rng.name = dev_name(&dev->dev);
+	rngdev->rng.data_present = tx4939_rng_data_present;
+	rngdev->rng.data_read = tx4939_rng_data_read;
+
+	rng_io_start();
+	/* Reset RNG */
+	write_rng(TX4939_RNG_RCSR_RST, rngdev->base, TX4939_RNG_RCSR);
+	write_rng(0, rngdev->base, TX4939_RNG_RCSR);
+	/* Start RNG */
+	write_rng(TX4939_RNG_RCSR_ST, rngdev->base, TX4939_RNG_RCSR);
+	rng_io_end();
+	/*
+	 * Drop first two results.  From the datasheet:
+	 * The quality of the random numbers generated immediately
+	 * after reset can be insufficient.  Therefore, do not use
+	 * random numbers obtained from the first and second
+	 * generations; use the ones from the third or subsequent
+	 * generation.
+	 */
+	for (i = 0; i < 2; i++) {
+		rngdev->data_avail = 0;
+		if (!tx4939_rng_data_present(&rngdev->rng, 1))
+			return -EIO;
+	}
+
+	platform_set_drvdata(dev, rngdev);
+	return hwrng_register(&rngdev->rng);
+}
+
+static int __exit tx4939_rng_remove(struct platform_device *dev)
+{
+	struct tx4939_rng *rngdev = platform_get_drvdata(dev);
+
+	hwrng_unregister(&rngdev->rng);
+	return 0;
+}
+
+static struct platform_driver tx4939_rng_driver = {
+	.driver		= {
+		.name	= "tx4939-rng",
+		.owner	= THIS_MODULE,
+	},
+	.remove = tx4939_rng_remove,
+};
+
+module_platform_driver_probe(tx4939_rng_driver, tx4939_rng_probe);
+
+MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver for TX4939");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/via-rng.c

@@ -0,0 +1,231 @@
+/*
+ * RNG driver for VIA RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <crypto/padlock.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <asm/cpu_device_id.h>
+#include <asm/io.h>
+#include <asm/msr.h>
+#include <asm/cpufeature.h>
+#include <asm/i387.h>
+
+
+
+
+enum {
+	VIA_STRFILT_CNT_SHIFT	= 16,
+	VIA_STRFILT_FAIL	= (1 << 15),
+	VIA_STRFILT_ENABLE	= (1 << 14),
+	VIA_RAWBITS_ENABLE	= (1 << 13),
+	VIA_RNG_ENABLE		= (1 << 6),
+	VIA_NOISESRC1		= (1 << 8),
+	VIA_NOISESRC2		= (1 << 9),
+	VIA_XSTORE_CNT_MASK	= 0x0F,
+
+	VIA_RNG_CHUNK_8		= 0x00,	/* 64 rand bits, 64 stored bits */
+	VIA_RNG_CHUNK_4		= 0x01,	/* 32 rand bits, 32 stored bits */
+	VIA_RNG_CHUNK_4_MASK	= 0xFFFFFFFF,
+	VIA_RNG_CHUNK_2		= 0x02,	/* 16 rand bits, 32 stored bits */
+	VIA_RNG_CHUNK_2_MASK	= 0xFFFF,
+	VIA_RNG_CHUNK_1		= 0x03,	/* 8 rand bits, 32 stored bits */
+	VIA_RNG_CHUNK_1_MASK	= 0xFF,
+};
+
+/*
+ * Investigate using the 'rep' prefix to obtain 32 bits of random data
+ * in one insn.  The upside is potentially better performance.  The
+ * downside is that the instruction becomes no longer atomic.  Due to
+ * this, just like familiar issues with /dev/random itself, the worst
+ * case of a 'rep xstore' could potentially pause a cpu for an
+ * unreasonably long time.  In practice, this condition would likely
+ * only occur when the hardware is failing.  (or so we hope :))
+ *
+ * Another possible performance boost may come from simply buffering
+ * until we have 4 bytes, thus returning a u32 at a time,
+ * instead of the current u8-at-a-time.
+ *
+ * Padlock instructions can generate a spurious DNA fault, so
+ * we have to call them in the context of irq_ts_save/restore()
+ */
+
+static inline u32 xstore(u32 *addr, u32 edx_in)
+{
+	u32 eax_out;
+	int ts_state;
+
+	ts_state = irq_ts_save();
+
+	asm(".byte 0x0F,0xA7,0xC0 /* xstore %%edi (addr=%0) */"
+		: "=m" (*addr), "=a" (eax_out), "+d" (edx_in), "+D" (addr));
+
+	irq_ts_restore(ts_state);
+	return eax_out;
+}
+
+static int via_rng_data_present(struct hwrng *rng, int wait)
+{
+	char buf[16 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
+		((aligned(STACK_ALIGN)));
+	u32 *via_rng_datum = (u32 *)PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
+	u32 bytes_out;
+	int i;
+
+	/* We choose the recommended 1-byte-per-instruction RNG rate,
+	 * for greater randomness at the expense of speed.  Larger
+	 * values 2, 4, or 8 bytes-per-instruction yield greater
+	 * speed at lesser randomness.
+	 *
+	 * If you change this to another VIA_CHUNK_n, you must also
+	 * change the ->n_bytes values in rng_vendor_ops[] tables.
+	 * VIA_CHUNK_8 requires further code changes.
+	 *
+	 * A copy of MSR_VIA_RNG is placed in eax_out when xstore
+	 * completes.
+	 */
+
+	for (i = 0; i < 20; i++) {
+		*via_rng_datum = 0; /* paranoia, not really necessary */
+		bytes_out = xstore(via_rng_datum, VIA_RNG_CHUNK_1);
+		bytes_out &= VIA_XSTORE_CNT_MASK;
+		if (bytes_out || !wait)
+			break;
+		udelay(10);
+	}
+	rng->priv = *via_rng_datum;
+	return bytes_out ? 1 : 0;
+}
+
+static int via_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	u32 via_rng_datum = (u32)rng->priv;
+
+	*data = via_rng_datum;
+
+	return 1;
+}
+
+static int via_rng_init(struct hwrng *rng)
+{
+	struct cpuinfo_x86 *c = &cpu_data(0);
+	u32 lo, hi, old_lo;
+
+	/* VIA Nano CPUs don't have the MSR_VIA_RNG anymore.  The RNG
+	 * is always enabled if CPUID rng_en is set.  There is no
+	 * RNG configuration like it used to be the case in this
+	 * register */
+	if ((c->x86 == 6) && (c->x86_model >= 0x0f)) {
+		if (!cpu_has_xstore_enabled) {
+			pr_err(PFX "can't enable hardware RNG "
+				"if XSTORE is not enabled\n");
+			return -ENODEV;
+		}
+		return 0;
+	}
+
+	/* Control the RNG via MSR.  Tread lightly and pay very close
+	 * close attention to values written, as the reserved fields
+	 * are documented to be "undefined and unpredictable"; but it
+	 * does not say to write them as zero, so I make a guess that
+	 * we restore the values we find in the register.
+	 */
+	rdmsr(MSR_VIA_RNG, lo, hi);
+
+	old_lo = lo;
+	lo &= ~(0x7f << VIA_STRFILT_CNT_SHIFT);
+	lo &= ~VIA_XSTORE_CNT_MASK;
+	lo &= ~(VIA_STRFILT_ENABLE | VIA_STRFILT_FAIL | VIA_RAWBITS_ENABLE);
+	lo |= VIA_RNG_ENABLE;
+	lo |= VIA_NOISESRC1;
+
+	/* Enable secondary noise source on CPUs where it is present. */
+
+	/* Nehemiah stepping 8 and higher */
+	if ((c->x86_model == 9) && (c->x86_mask > 7))
+		lo |= VIA_NOISESRC2;
+
+	/* Esther */
+	if (c->x86_model >= 10)
+		lo |= VIA_NOISESRC2;
+
+	if (lo != old_lo)
+		wrmsr(MSR_VIA_RNG, lo, hi);
+
+	/* perhaps-unnecessary sanity check; remove after testing if
+	   unneeded */
+	rdmsr(MSR_VIA_RNG, lo, hi);
+	if ((lo & VIA_RNG_ENABLE) == 0) {
+		pr_err(PFX "cannot enable VIA C3 RNG, aborting\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+
+static struct hwrng via_rng = {
+	.name		= "via",
+	.init		= via_rng_init,
+	.data_present	= via_rng_data_present,
+	.data_read	= via_rng_data_read,
+};
+
+
+static int __init mod_init(void)
+{
+	int err;
+
+	if (!cpu_has_xstore)
+		return -ENODEV;
+	pr_info("VIA RNG detected\n");
+	err = hwrng_register(&via_rng);
+	if (err) {
+		pr_err(PFX "RNG registering failed (%d)\n",
+		       err);
+		goto out;
+	}
+out:
+	return err;
+}
+
+static void __exit mod_exit(void)
+{
+	hwrng_unregister(&via_rng);
+}
+
+module_init(mod_init);
+module_exit(mod_exit);
+
+static struct x86_cpu_id __maybe_unused via_rng_cpu_id[] = {
+	X86_FEATURE_MATCH(X86_FEATURE_XSTORE),
+	{}
+};
+
+MODULE_DESCRIPTION("H/W RNG driver for VIA CPU with PadLock");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(x86cpu, via_rng_cpu_id);

drivers/char/hw_random/virtio-rng.c

@@ -0,0 +1,213 @@
+/*
+ * Randomness driver for virtio
+ *  Copyright (C) 2007, 2008 Rusty Russell IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#include <linux/err.h>
+#include <linux/hw_random.h>
+#include <linux/scatterlist.h>
+#include <linux/spinlock.h>
+#include <linux/virtio.h>
+#include <linux/virtio_rng.h>
+#include <linux/module.h>
+
+static DEFINE_IDA(rng_index_ida);
+
+struct virtrng_info {
+	struct hwrng hwrng;
+	struct virtqueue *vq;
+	struct completion have_data;
+	char name[25];
+	unsigned int data_avail;
+	int index;
+	bool busy;
+	bool hwrng_register_done;
+	bool hwrng_removed;
+};
+
+
+static void random_recv_done(struct virtqueue *vq)
+{
+	struct virtrng_info *vi = vq->vdev->priv;
+
+	/* We can get spurious callbacks, e.g. shared IRQs + virtio_pci. */
+	if (!virtqueue_get_buf(vi->vq, &vi->data_avail))
+		return;
+
+	complete(&vi->have_data);
+}
+
+/* The host will fill any buffer we give it with sweet, sweet randomness. */
+static void register_buffer(struct virtrng_info *vi, u8 *buf, size_t size)
+{
+	struct scatterlist sg;
+
+	sg_init_one(&sg, buf, size);
+
+	/* There should always be room for one buffer. */
+	virtqueue_add_inbuf(vi->vq, &sg, 1, buf, GFP_KERNEL);
+
+	virtqueue_kick(vi->vq);
+}
+
+static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait)
+{
+	int ret;
+	struct virtrng_info *vi = (struct virtrng_info *)rng->priv;
+
+	if (vi->hwrng_removed)
+		return -ENODEV;
+
+	if (!vi->busy) {
+		vi->busy = true;
+		init_completion(&vi->have_data);
+		register_buffer(vi, buf, size);
+	}
+
+	if (!wait)
+		return 0;
+
+	ret = wait_for_completion_killable(&vi->have_data);
+	if (ret < 0)
+		return ret;
+
+	vi->busy = false;
+
+	return vi->data_avail;
+}
+
+static void virtio_cleanup(struct hwrng *rng)
+{
+	struct virtrng_info *vi = (struct virtrng_info *)rng->priv;
+
+	if (vi->busy)
+		wait_for_completion(&vi->have_data);
+}
+
+static int probe_common(struct virtio_device *vdev)
+{
+	int err, index;
+	struct virtrng_info *vi = NULL;
+
+	vi = kzalloc(sizeof(struct virtrng_info), GFP_KERNEL);
+	if (!vi)
+		return -ENOMEM;
+
+	vi->index = index = ida_simple_get(&rng_index_ida, 0, 0, GFP_KERNEL);
+	if (index < 0) {
+		err = index;
+		goto err_ida;
+	}
+	sprintf(vi->name, "virtio_rng.%d", index);
+	init_completion(&vi->have_data);
+
+	vi->hwrng = (struct hwrng) {
+		.read = virtio_read,
+		.cleanup = virtio_cleanup,
+		.priv = (unsigned long)vi,
+		.name = vi->name,
+		.quality = 1000,
+	};
+	vdev->priv = vi;
+
+	/* We expect a single virtqueue. */
+	vi->vq = virtio_find_single_vq(vdev, random_recv_done, "input");
+	if (IS_ERR(vi->vq)) {
+		err = PTR_ERR(vi->vq);
+		goto err_find;
+	}
+
+	return 0;
+
+err_find:
+	ida_simple_remove(&rng_index_ida, index);
+err_ida:
+	kfree(vi);
+	return err;
+}
+
+static void remove_common(struct virtio_device *vdev)
+{
+	struct virtrng_info *vi = vdev->priv;
+
+	vi->hwrng_removed = true;
+	vi->data_avail = 0;
+	complete(&vi->have_data);
+	vdev->config->reset(vdev);
+	vi->busy = false;
+	if (vi->hwrng_register_done)
+		hwrng_unregister(&vi->hwrng);
+	vdev->config->del_vqs(vdev);
+	ida_simple_remove(&rng_index_ida, vi->index);
+	kfree(vi);
+}
+
+static int virtrng_probe(struct virtio_device *vdev)
+{
+	return probe_common(vdev);
+}
+
+static void virtrng_remove(struct virtio_device *vdev)
+{
+	remove_common(vdev);
+}
+
+static void virtrng_scan(struct virtio_device *vdev)
+{
+	struct virtrng_info *vi = vdev->priv;
+	int err;
+
+	err = hwrng_register(&vi->hwrng);
+	if (!err)
+		vi->hwrng_register_done = true;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int virtrng_freeze(struct virtio_device *vdev)
+{
+	remove_common(vdev);
+	return 0;
+}
+
+static int virtrng_restore(struct virtio_device *vdev)
+{
+	return probe_common(vdev);
+}
+#endif
+
+static struct virtio_device_id id_table[] = {
+	{ VIRTIO_ID_RNG, VIRTIO_DEV_ANY_ID },
+	{ 0 },
+};
+
+static struct virtio_driver virtio_rng_driver = {
+	.driver.name =	KBUILD_MODNAME,
+	.driver.owner =	THIS_MODULE,
+	.id_table =	id_table,
+	.probe =	virtrng_probe,
+	.remove =	virtrng_remove,
+	.scan =		virtrng_scan,
+#ifdef CONFIG_PM_SLEEP
+	.freeze =	virtrng_freeze,
+	.restore =	virtrng_restore,
+#endif
+};
+
+module_virtio_driver(virtio_rng_driver);
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_DESCRIPTION("Virtio random number driver");
+MODULE_LICENSE("GPL");

drivers/char/hw_random/xgene-rng.c

@@ -0,0 +1,423 @@
+/*
+ * APM X-Gene SoC RNG Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Rameshwar Prasad Sahu <rsahu@apm.com>
+ *	   Shamal Winchurkar <swinchurkar@apm.com>
+ *	   Feng Kan <fkan@apm.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/hw_random.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/timer.h>
+
+#define RNG_MAX_DATUM			4
+#define MAX_TRY				100
+#define XGENE_RNG_RETRY_COUNT		20
+#define XGENE_RNG_RETRY_INTERVAL	10
+
+/* RNG  Registers */
+#define RNG_INOUT_0			0x00
+#define RNG_INTR_STS_ACK		0x10
+#define RNG_CONTROL			0x14
+#define RNG_CONFIG			0x18
+#define RNG_ALARMCNT			0x1c
+#define RNG_FROENABLE			0x20
+#define RNG_FRODETUNE			0x24
+#define RNG_ALARMMASK			0x28
+#define RNG_ALARMSTOP			0x2c
+#define RNG_OPTIONS			0x78
+#define RNG_EIP_REV			0x7c
+
+#define MONOBIT_FAIL_MASK		BIT(7)
+#define POKER_FAIL_MASK			BIT(6)
+#define LONG_RUN_FAIL_MASK		BIT(5)
+#define RUN_FAIL_MASK			BIT(4)
+#define NOISE_FAIL_MASK			BIT(3)
+#define STUCK_OUT_MASK			BIT(2)
+#define SHUTDOWN_OFLO_MASK		BIT(1)
+#define READY_MASK			BIT(0)
+
+#define MAJOR_HW_REV_RD(src)		(((src) & 0x0f000000) >> 24)
+#define MINOR_HW_REV_RD(src)		(((src) & 0x00f00000) >> 20)
+#define HW_PATCH_LEVEL_RD(src)		(((src) & 0x000f0000) >> 16)
+#define MAX_REFILL_CYCLES_SET(dst, src) \
+			((dst & ~0xffff0000) | (((u32)src << 16) & 0xffff0000))
+#define MIN_REFILL_CYCLES_SET(dst, src) \
+			((dst & ~0x000000ff) | (((u32)src) & 0x000000ff))
+#define ALARM_THRESHOLD_SET(dst, src) \
+			((dst & ~0x000000ff) | (((u32)src) & 0x000000ff))
+#define ENABLE_RNG_SET(dst, src) \
+			((dst & ~BIT(10)) | (((u32)src << 10) & BIT(10)))
+#define REGSPEC_TEST_MODE_SET(dst, src) \
+			((dst & ~BIT(8)) | (((u32)src << 8) & BIT(8)))
+#define MONOBIT_FAIL_MASK_SET(dst, src) \
+			((dst & ~BIT(7)) | (((u32)src << 7) & BIT(7)))
+#define POKER_FAIL_MASK_SET(dst, src) \
+			((dst & ~BIT(6)) | (((u32)src << 6) & BIT(6)))
+#define LONG_RUN_FAIL_MASK_SET(dst, src) \
+			((dst & ~BIT(5)) | (((u32)src << 5) & BIT(5)))
+#define RUN_FAIL_MASK_SET(dst, src) \
+			((dst & ~BIT(4)) | (((u32)src << 4) & BIT(4)))
+#define NOISE_FAIL_MASK_SET(dst, src) \
+			((dst & ~BIT(3)) | (((u32)src << 3) & BIT(3)))
+#define STUCK_OUT_MASK_SET(dst, src) \
+			((dst & ~BIT(2)) | (((u32)src << 2) & BIT(2)))
+#define SHUTDOWN_OFLO_MASK_SET(dst, src) \
+			((dst & ~BIT(1)) | (((u32)src << 1) & BIT(1)))
+
+struct xgene_rng_dev {
+	u32 irq;
+	void  __iomem *csr_base;
+	u32 revision;
+	u32 datum_size;
+	u32 failure_cnt;	/* Failure count last minute */
+	unsigned long failure_ts;/* First failure timestamp */
+	struct timer_list failure_timer;
+	struct device *dev;
+	struct clk *clk;
+};
+
+static void xgene_rng_expired_timer(unsigned long arg)
+{
+	struct xgene_rng_dev *ctx = (struct xgene_rng_dev *) arg;
+
+	/* Clear failure counter as timer expired */
+	disable_irq(ctx->irq);
+	ctx->failure_cnt = 0;
+	del_timer(&ctx->failure_timer);
+	enable_irq(ctx->irq);
+}
+
+static void xgene_rng_start_timer(struct xgene_rng_dev *ctx)
+{
+	ctx->failure_timer.data = (unsigned long) ctx;
+	ctx->failure_timer.function = xgene_rng_expired_timer;
+	ctx->failure_timer.expires = jiffies + 120 * HZ;
+	add_timer(&ctx->failure_timer);
+}
+
+/*
+ * Initialize or reinit free running oscillators (FROs)
+ */
+static void xgene_rng_init_fro(struct xgene_rng_dev *ctx, u32 fro_val)
+{
+	writel(fro_val, ctx->csr_base + RNG_FRODETUNE);
+	writel(0x00000000, ctx->csr_base + RNG_ALARMMASK);
+	writel(0x00000000, ctx->csr_base + RNG_ALARMSTOP);
+	writel(0xFFFFFFFF, ctx->csr_base + RNG_FROENABLE);
+}
+
+static void xgene_rng_chk_overflow(struct xgene_rng_dev *ctx)
+{
+	u32 val;
+
+	val = readl(ctx->csr_base + RNG_INTR_STS_ACK);
+	if (val & MONOBIT_FAIL_MASK)
+		/*
+		 * LFSR detected an out-of-bounds number of 1s after
+		 * checking 20,000 bits (test T1 as specified in the
+		 * AIS-31 standard)
+		 */
+		dev_err(ctx->dev, "test monobit failure error 0x%08X\n", val);
+	if (val & POKER_FAIL_MASK)
+		/*
+		 * LFSR detected an out-of-bounds value in at least one
+		 * of the 16 poker_count_X counters or an out of bounds sum
+		 * of squares value after checking 20,000 bits (test T2 as
+		 * specified in the AIS-31 standard)
+		 */
+		dev_err(ctx->dev, "test poker failure error 0x%08X\n", val);
+	if (val & LONG_RUN_FAIL_MASK)
+		/*
+		 * LFSR detected a sequence of 34 identical bits
+		 * (test T4 as specified in the AIS-31 standard)
+		 */
+		dev_err(ctx->dev, "test long run failure error 0x%08X\n", val);
+	if (val & RUN_FAIL_MASK)
+		/*
+		 * LFSR detected an outof-bounds value for at least one
+		 * of the running counters after checking 20,000 bits
+		 * (test T3 as specified in the AIS-31 standard)
+		 */
+		dev_err(ctx->dev, "test run failure error 0x%08X\n", val);
+	if (val & NOISE_FAIL_MASK)
+		/* LFSR detected a sequence of 48 identical bits */
+		dev_err(ctx->dev, "noise failure error 0x%08X\n", val);
+	if (val & STUCK_OUT_MASK)
+		/*
+		 * Detected output data registers generated same value twice
+		 * in a row
+		 */
+		dev_err(ctx->dev, "stuck out failure error 0x%08X\n", val);
+
+	if (val & SHUTDOWN_OFLO_MASK) {
+		u32 frostopped;
+
+		/* FROs shut down after a second error event. Try recover. */
+		if (++ctx->failure_cnt == 1) {
+			/* 1st time, just recover */
+			ctx->failure_ts = jiffies;
+			frostopped = readl(ctx->csr_base + RNG_ALARMSTOP);
+			xgene_rng_init_fro(ctx, frostopped);
+
+			/*
+			 * We must start a timer to clear out this error
+			 * in case the system timer wrap around
+			 */
+			xgene_rng_start_timer(ctx);
+		} else {
+			/* 2nd time failure in lesser than 1 minute? */
+			if (time_after(ctx->failure_ts + 60 * HZ, jiffies)) {
+				dev_err(ctx->dev,
+					"FRO shutdown failure error 0x%08X\n",
+					val);
+			} else {
+				/* 2nd time failure after 1 minutes, recover */
+				ctx->failure_ts = jiffies;
+				ctx->failure_cnt = 1;
+				/*
+				 * We must start a timer to clear out this
+				 * error in case the system timer wrap
+				 * around
+				 */
+				xgene_rng_start_timer(ctx);
+			}
+			frostopped = readl(ctx->csr_base + RNG_ALARMSTOP);
+			xgene_rng_init_fro(ctx, frostopped);
+		}
+	}
+	/* Clear them all */
+	writel(val, ctx->csr_base + RNG_INTR_STS_ACK);
+}
+
+static irqreturn_t xgene_rng_irq_handler(int irq, void *id)
+{
+	struct xgene_rng_dev *ctx = (struct xgene_rng_dev *) id;
+
+	/* RNG Alarm Counter overflow */
+	xgene_rng_chk_overflow(ctx);
+
+	return IRQ_HANDLED;
+}
+
+static int xgene_rng_data_present(struct hwrng *rng, int wait)
+{
+	struct xgene_rng_dev *ctx = (struct xgene_rng_dev *) rng->priv;
+	u32 i, val = 0;
+
+	for (i = 0; i < XGENE_RNG_RETRY_COUNT; i++) {
+		val = readl(ctx->csr_base + RNG_INTR_STS_ACK);
+		if ((val & READY_MASK) || !wait)
+			break;
+		udelay(XGENE_RNG_RETRY_INTERVAL);
+	}
+
+	return (val & READY_MASK);
+}
+
+static int xgene_rng_data_read(struct hwrng *rng, u32 *data)
+{
+	struct xgene_rng_dev *ctx = (struct xgene_rng_dev *) rng->priv;
+	int i;
+
+	for (i = 0; i < ctx->datum_size; i++)
+		data[i] = readl(ctx->csr_base + RNG_INOUT_0 + i * 4);
+
+	/* Clear ready bit to start next transaction */
+	writel(READY_MASK, ctx->csr_base + RNG_INTR_STS_ACK);
+
+	return ctx->datum_size << 2;
+}
+
+static void xgene_rng_init_internal(struct xgene_rng_dev *ctx)
+{
+	u32 val;
+
+	writel(0x00000000, ctx->csr_base + RNG_CONTROL);
+
+	val = MAX_REFILL_CYCLES_SET(0, 10);
+	val = MIN_REFILL_CYCLES_SET(val, 10);
+	writel(val, ctx->csr_base + RNG_CONFIG);
+
+	val = ALARM_THRESHOLD_SET(0, 0xFF);
+	writel(val, ctx->csr_base + RNG_ALARMCNT);
+
+	xgene_rng_init_fro(ctx, 0);
+
+	writel(MONOBIT_FAIL_MASK |
+		POKER_FAIL_MASK	|
+		LONG_RUN_FAIL_MASK |
+		RUN_FAIL_MASK |
+		NOISE_FAIL_MASK |
+		STUCK_OUT_MASK |
+		SHUTDOWN_OFLO_MASK |
+		READY_MASK, ctx->csr_base + RNG_INTR_STS_ACK);
+
+	val = ENABLE_RNG_SET(0, 1);
+	val = MONOBIT_FAIL_MASK_SET(val, 1);
+	val = POKER_FAIL_MASK_SET(val, 1);
+	val = LONG_RUN_FAIL_MASK_SET(val, 1);
+	val = RUN_FAIL_MASK_SET(val, 1);
+	val = NOISE_FAIL_MASK_SET(val, 1);
+	val = STUCK_OUT_MASK_SET(val, 1);
+	val = SHUTDOWN_OFLO_MASK_SET(val, 1);
+	writel(val, ctx->csr_base + RNG_CONTROL);
+}
+
+static int xgene_rng_init(struct hwrng *rng)
+{
+	struct xgene_rng_dev *ctx = (struct xgene_rng_dev *) rng->priv;
+
+	ctx->failure_cnt = 0;
+	init_timer(&ctx->failure_timer);
+
+	ctx->revision = readl(ctx->csr_base + RNG_EIP_REV);
+
+	dev_dbg(ctx->dev, "Rev %d.%d.%d\n",
+		MAJOR_HW_REV_RD(ctx->revision),
+		MINOR_HW_REV_RD(ctx->revision),
+		HW_PATCH_LEVEL_RD(ctx->revision));
+
+	dev_dbg(ctx->dev, "Options 0x%08X",
+		readl(ctx->csr_base + RNG_OPTIONS));
+
+	xgene_rng_init_internal(ctx);
+
+	ctx->datum_size = RNG_MAX_DATUM;
+
+	return 0;
+}
+
+static struct hwrng xgene_rng_func = {
+	.name		= "xgene-rng",
+	.init		= xgene_rng_init,
+	.data_present	= xgene_rng_data_present,
+	.data_read	= xgene_rng_data_read,
+};
+
+static int xgene_rng_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct xgene_rng_dev *ctx;
+	int rc = 0;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->dev = &pdev->dev;
+	platform_set_drvdata(pdev, ctx);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ctx->csr_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(ctx->csr_base))
+		return PTR_ERR(ctx->csr_base);
+
+	ctx->irq = platform_get_irq(pdev, 0);
+	if (ctx->irq < 0) {
+		dev_err(&pdev->dev, "No IRQ resource\n");
+		return ctx->irq;
+	}
+
+	dev_dbg(&pdev->dev, "APM X-Gene RNG BASE %p ALARM IRQ %d",
+		ctx->csr_base, ctx->irq);
+
+	rc = devm_request_irq(&pdev->dev, ctx->irq, xgene_rng_irq_handler, 0,
+				dev_name(&pdev->dev), ctx);
+	if (rc) {
+		dev_err(&pdev->dev, "Could not request RNG alarm IRQ\n");
+		return rc;
+	}
+
+	/* Enable IP clock */
+	ctx->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(ctx->clk)) {
+		dev_warn(&pdev->dev, "Couldn't get the clock for RNG\n");
+	} else {
+		rc = clk_prepare_enable(ctx->clk);
+		if (rc) {
+			dev_warn(&pdev->dev,
+				 "clock prepare enable failed for RNG");
+			return rc;
+		}
+	}
+
+	xgene_rng_func.priv = (unsigned long) ctx;
+
+	rc = hwrng_register(&xgene_rng_func);
+	if (rc) {
+		dev_err(&pdev->dev, "RNG registering failed error %d\n", rc);
+		if (!IS_ERR(ctx->clk))
+			clk_disable_unprepare(ctx->clk);
+		return rc;
+	}
+
+	rc = device_init_wakeup(&pdev->dev, 1);
+	if (rc) {
+		dev_err(&pdev->dev, "RNG device_init_wakeup failed error %d\n",
+			rc);
+		if (!IS_ERR(ctx->clk))
+			clk_disable_unprepare(ctx->clk);
+		hwrng_unregister(&xgene_rng_func);
+		return rc;
+	}
+
+	return 0;
+}
+
+static int xgene_rng_remove(struct platform_device *pdev)
+{
+	struct xgene_rng_dev *ctx = platform_get_drvdata(pdev);
+	int rc;
+
+	rc = device_init_wakeup(&pdev->dev, 0);
+	if (rc)
+		dev_err(&pdev->dev, "RNG init wakeup failed error %d\n", rc);
+	if (!IS_ERR(ctx->clk))
+		clk_disable_unprepare(ctx->clk);
+	hwrng_unregister(&xgene_rng_func);
+
+	return rc;
+}
+
+static const struct of_device_id xgene_rng_of_match[] = {
+	{ .compatible = "apm,xgene-rng" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, xgene_rng_of_match);
+
+static struct platform_driver xgene_rng_driver = {
+	.probe = xgene_rng_probe,
+	.remove	= xgene_rng_remove,
+	.driver = {
+		.name		= "xgene-rng",
+		.of_match_table = xgene_rng_of_match,
+	},
+};
+
+module_platform_driver(xgene_rng_driver);
+MODULE_DESCRIPTION("APM X-Gene RNG driver");
+MODULE_LICENSE("GPL");