Fixed MTP to work with TWRP

drivers/firmware/efi/Kconfig

@@ -0,0 +1,66 @@
+menu "EFI (Extensible Firmware Interface) Support"
+	depends on EFI
+
+config EFI_VARS
+	tristate "EFI Variable Support via sysfs"
+	depends on EFI
+	default n
+	help
+	  If you say Y here, you are able to get EFI (Extensible Firmware
+	  Interface) variable information via sysfs.  You may read,
+	  write, create, and destroy EFI variables through this interface.
+
+	  Note that using this driver in concert with efibootmgr requires
+	  at least test release version 0.5.0-test3 or later, which is
+	  available from Matt Domsch's website located at:
+	  <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>
+
+	  Subsequent efibootmgr releases may be found at:
+	  <http://linux.dell.com/efibootmgr>
+
+config EFI_VARS_PSTORE
+	tristate "Register efivars backend for pstore"
+	depends on EFI_VARS && PSTORE
+	default y
+	help
+	  Say Y here to enable use efivars as a backend to pstore. This
+	  will allow writing console messages, crash dumps, or anything
+	  else supported by pstore to EFI variables.
+
+config EFI_VARS_PSTORE_DEFAULT_DISABLE
+	bool "Disable using efivars as a pstore backend by default"
+	depends on EFI_VARS_PSTORE
+	default n
+	help
+	  Saying Y here will disable the use of efivars as a storage
+	  backend for pstore by default. This setting can be overridden
+	  using the efivars module's pstore_disable parameter.
+
+config EFI_RUNTIME_MAP
+	bool "Export efi runtime maps to sysfs"
+	depends on X86 && EFI && KEXEC
+	default y
+	help
+	  Export efi runtime memory maps to /sys/firmware/efi/runtime-map.
+	  That memory map is used for example by kexec to set up efi virtual
+	  mapping the 2nd kernel, but can also be used for debugging purposes.
+
+	  See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map.
+
+config EFI_PARAMS_FROM_FDT
+	bool
+	help
+	  Select this config option from the architecture Kconfig if
+	  the EFI runtime support gets system table address, memory
+          map address, and other parameters from the device tree.
+
+config EFI_RUNTIME_WRAPPERS
+	bool
+
+config EFI_ARMSTUB
+	bool
+
+endmenu
+
+config UEFI_CPER
+	bool

drivers/firmware/efi/Makefile

@@ -0,0 +1,10 @@
+#
+# Makefile for linux kernel
+#
+obj-$(CONFIG_EFI)			+= efi.o vars.o reboot.o
+obj-$(CONFIG_EFI_VARS)			+= efivars.o
+obj-$(CONFIG_EFI_VARS_PSTORE)		+= efi-pstore.o
+obj-$(CONFIG_UEFI_CPER)			+= cper.o
+obj-$(CONFIG_EFI_RUNTIME_MAP)		+= runtime-map.o
+obj-$(CONFIG_EFI_RUNTIME_WRAPPERS)	+= runtime-wrappers.o
+obj-$(CONFIG_EFI_ARM_STUB)		+= libstub/

drivers/firmware/efi/cper.c

@@ -0,0 +1,492 @@
+/*
+ * UEFI Common Platform Error Record (CPER) support
+ *
+ * Copyright (C) 2010, Intel Corp.
+ *	Author: Huang Ying <ying.huang@intel.com>
+ *
+ * CPER is the format used to describe platform hardware error by
+ * various tables, such as ERST, BERT and HEST etc.
+ *
+ * For more information about CPER, please refer to Appendix N of UEFI
+ * Specification version 2.4.
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/time.h>
+#include <linux/cper.h>
+#include <linux/dmi.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+#include <linux/aer.h>
+
+#define INDENT_SP	" "
+
+static char rcd_decode_str[CPER_REC_LEN];
+
+/*
+ * CPER record ID need to be unique even after reboot, because record
+ * ID is used as index for ERST storage, while CPER records from
+ * multiple boot may co-exist in ERST.
+ */
+u64 cper_next_record_id(void)
+{
+	static atomic64_t seq;
+
+	if (!atomic64_read(&seq))
+		atomic64_set(&seq, ((u64)get_seconds()) << 32);
+
+	return atomic64_inc_return(&seq);
+}
+EXPORT_SYMBOL_GPL(cper_next_record_id);
+
+static const char * const severity_strs[] = {
+	"recoverable",
+	"fatal",
+	"corrected",
+	"info",
+};
+
+const char *cper_severity_str(unsigned int severity)
+{
+	return severity < ARRAY_SIZE(severity_strs) ?
+		severity_strs[severity] : "unknown";
+}
+EXPORT_SYMBOL_GPL(cper_severity_str);
+
+/*
+ * cper_print_bits - print strings for set bits
+ * @pfx: prefix for each line, including log level and prefix string
+ * @bits: bit mask
+ * @strs: string array, indexed by bit position
+ * @strs_size: size of the string array: @strs
+ *
+ * For each set bit in @bits, print the corresponding string in @strs.
+ * If the output length is longer than 80, multiple line will be
+ * printed, with @pfx is printed at the beginning of each line.
+ */
+void cper_print_bits(const char *pfx, unsigned int bits,
+		     const char * const strs[], unsigned int strs_size)
+{
+	int i, len = 0;
+	const char *str;
+	char buf[84];
+
+	for (i = 0; i < strs_size; i++) {
+		if (!(bits & (1U << i)))
+			continue;
+		str = strs[i];
+		if (!str)
+			continue;
+		if (len && len + strlen(str) + 2 > 80) {
+			printk("%s\n", buf);
+			len = 0;
+		}
+		if (!len)
+			len = snprintf(buf, sizeof(buf), "%s%s", pfx, str);
+		else
+			len += snprintf(buf+len, sizeof(buf)-len, ", %s", str);
+	}
+	if (len)
+		printk("%s\n", buf);
+}
+
+static const char * const proc_type_strs[] = {
+	"IA32/X64",
+	"IA64",
+};
+
+static const char * const proc_isa_strs[] = {
+	"IA32",
+	"IA64",
+	"X64",
+};
+
+static const char * const proc_error_type_strs[] = {
+	"cache error",
+	"TLB error",
+	"bus error",
+	"micro-architectural error",
+};
+
+static const char * const proc_op_strs[] = {
+	"unknown or generic",
+	"data read",
+	"data write",
+	"instruction execution",
+};
+
+static const char * const proc_flag_strs[] = {
+	"restartable",
+	"precise IP",
+	"overflow",
+	"corrected",
+};
+
+static void cper_print_proc_generic(const char *pfx,
+				    const struct cper_sec_proc_generic *proc)
+{
+	if (proc->validation_bits & CPER_PROC_VALID_TYPE)
+		printk("%s""processor_type: %d, %s\n", pfx, proc->proc_type,
+		       proc->proc_type < ARRAY_SIZE(proc_type_strs) ?
+		       proc_type_strs[proc->proc_type] : "unknown");
+	if (proc->validation_bits & CPER_PROC_VALID_ISA)
+		printk("%s""processor_isa: %d, %s\n", pfx, proc->proc_isa,
+		       proc->proc_isa < ARRAY_SIZE(proc_isa_strs) ?
+		       proc_isa_strs[proc->proc_isa] : "unknown");
+	if (proc->validation_bits & CPER_PROC_VALID_ERROR_TYPE) {
+		printk("%s""error_type: 0x%02x\n", pfx, proc->proc_error_type);
+		cper_print_bits(pfx, proc->proc_error_type,
+				proc_error_type_strs,
+				ARRAY_SIZE(proc_error_type_strs));
+	}
+	if (proc->validation_bits & CPER_PROC_VALID_OPERATION)
+		printk("%s""operation: %d, %s\n", pfx, proc->operation,
+		       proc->operation < ARRAY_SIZE(proc_op_strs) ?
+		       proc_op_strs[proc->operation] : "unknown");
+	if (proc->validation_bits & CPER_PROC_VALID_FLAGS) {
+		printk("%s""flags: 0x%02x\n", pfx, proc->flags);
+		cper_print_bits(pfx, proc->flags, proc_flag_strs,
+				ARRAY_SIZE(proc_flag_strs));
+	}
+	if (proc->validation_bits & CPER_PROC_VALID_LEVEL)
+		printk("%s""level: %d\n", pfx, proc->level);
+	if (proc->validation_bits & CPER_PROC_VALID_VERSION)
+		printk("%s""version_info: 0x%016llx\n", pfx, proc->cpu_version);
+	if (proc->validation_bits & CPER_PROC_VALID_ID)
+		printk("%s""processor_id: 0x%016llx\n", pfx, proc->proc_id);
+	if (proc->validation_bits & CPER_PROC_VALID_TARGET_ADDRESS)
+		printk("%s""target_address: 0x%016llx\n",
+		       pfx, proc->target_addr);
+	if (proc->validation_bits & CPER_PROC_VALID_REQUESTOR_ID)
+		printk("%s""requestor_id: 0x%016llx\n",
+		       pfx, proc->requestor_id);
+	if (proc->validation_bits & CPER_PROC_VALID_RESPONDER_ID)
+		printk("%s""responder_id: 0x%016llx\n",
+		       pfx, proc->responder_id);
+	if (proc->validation_bits & CPER_PROC_VALID_IP)
+		printk("%s""IP: 0x%016llx\n", pfx, proc->ip);
+}
+
+static const char * const mem_err_type_strs[] = {
+	"unknown",
+	"no error",
+	"single-bit ECC",
+	"multi-bit ECC",
+	"single-symbol chipkill ECC",
+	"multi-symbol chipkill ECC",
+	"master abort",
+	"target abort",
+	"parity error",
+	"watchdog timeout",
+	"invalid address",
+	"mirror Broken",
+	"memory sparing",
+	"scrub corrected error",
+	"scrub uncorrected error",
+	"physical memory map-out event",
+};
+
+const char *cper_mem_err_type_str(unsigned int etype)
+{
+	return etype < ARRAY_SIZE(mem_err_type_strs) ?
+		mem_err_type_strs[etype] : "unknown";
+}
+EXPORT_SYMBOL_GPL(cper_mem_err_type_str);
+
+static int cper_mem_err_location(struct cper_mem_err_compact *mem, char *msg)
+{
+	u32 len, n;
+
+	if (!msg)
+		return 0;
+
+	n = 0;
+	len = CPER_REC_LEN - 1;
+	if (mem->validation_bits & CPER_MEM_VALID_NODE)
+		n += scnprintf(msg + n, len - n, "node: %d ", mem->node);
+	if (mem->validation_bits & CPER_MEM_VALID_CARD)
+		n += scnprintf(msg + n, len - n, "card: %d ", mem->card);
+	if (mem->validation_bits & CPER_MEM_VALID_MODULE)
+		n += scnprintf(msg + n, len - n, "module: %d ", mem->module);
+	if (mem->validation_bits & CPER_MEM_VALID_RANK_NUMBER)
+		n += scnprintf(msg + n, len - n, "rank: %d ", mem->rank);
+	if (mem->validation_bits & CPER_MEM_VALID_BANK)
+		n += scnprintf(msg + n, len - n, "bank: %d ", mem->bank);
+	if (mem->validation_bits & CPER_MEM_VALID_DEVICE)
+		n += scnprintf(msg + n, len - n, "device: %d ", mem->device);
+	if (mem->validation_bits & CPER_MEM_VALID_ROW)
+		n += scnprintf(msg + n, len - n, "row: %d ", mem->row);
+	if (mem->validation_bits & CPER_MEM_VALID_COLUMN)
+		n += scnprintf(msg + n, len - n, "column: %d ", mem->column);
+	if (mem->validation_bits & CPER_MEM_VALID_BIT_POSITION)
+		n += scnprintf(msg + n, len - n, "bit_position: %d ",
+			       mem->bit_pos);
+	if (mem->validation_bits & CPER_MEM_VALID_REQUESTOR_ID)
+		n += scnprintf(msg + n, len - n, "requestor_id: 0x%016llx ",
+			       mem->requestor_id);
+	if (mem->validation_bits & CPER_MEM_VALID_RESPONDER_ID)
+		n += scnprintf(msg + n, len - n, "responder_id: 0x%016llx ",
+			       mem->responder_id);
+	if (mem->validation_bits & CPER_MEM_VALID_TARGET_ID)
+		scnprintf(msg + n, len - n, "target_id: 0x%016llx ",
+			  mem->target_id);
+
+	msg[n] = '\0';
+	return n;
+}
+
+static int cper_dimm_err_location(struct cper_mem_err_compact *mem, char *msg)
+{
+	u32 len, n;
+	const char *bank = NULL, *device = NULL;
+
+	if (!msg || !(mem->validation_bits & CPER_MEM_VALID_MODULE_HANDLE))
+		return 0;
+
+	n = 0;
+	len = CPER_REC_LEN - 1;
+	dmi_memdev_name(mem->mem_dev_handle, &bank, &device);
+	if (bank && device)
+		n = snprintf(msg, len, "DIMM location: %s %s ", bank, device);
+	else
+		n = snprintf(msg, len,
+			     "DIMM location: not present. DMI handle: 0x%.4x ",
+			     mem->mem_dev_handle);
+
+	msg[n] = '\0';
+	return n;
+}
+
+void cper_mem_err_pack(const struct cper_sec_mem_err *mem,
+		       struct cper_mem_err_compact *cmem)
+{
+	cmem->validation_bits = mem->validation_bits;
+	cmem->node = mem->node;
+	cmem->card = mem->card;
+	cmem->module = mem->module;
+	cmem->bank = mem->bank;
+	cmem->device = mem->device;
+	cmem->row = mem->row;
+	cmem->column = mem->column;
+	cmem->bit_pos = mem->bit_pos;
+	cmem->requestor_id = mem->requestor_id;
+	cmem->responder_id = mem->responder_id;
+	cmem->target_id = mem->target_id;
+	cmem->rank = mem->rank;
+	cmem->mem_array_handle = mem->mem_array_handle;
+	cmem->mem_dev_handle = mem->mem_dev_handle;
+}
+
+const char *cper_mem_err_unpack(struct trace_seq *p,
+				struct cper_mem_err_compact *cmem)
+{
+	const char *ret = p->buffer + p->len;
+
+	if (cper_mem_err_location(cmem, rcd_decode_str))
+		trace_seq_printf(p, "%s", rcd_decode_str);
+	if (cper_dimm_err_location(cmem, rcd_decode_str))
+		trace_seq_printf(p, "%s", rcd_decode_str);
+	trace_seq_putc(p, '\0');
+
+	return ret;
+}
+
+static void cper_print_mem(const char *pfx, const struct cper_sec_mem_err *mem)
+{
+	struct cper_mem_err_compact cmem;
+
+	if (mem->validation_bits & CPER_MEM_VALID_ERROR_STATUS)
+		printk("%s""error_status: 0x%016llx\n", pfx, mem->error_status);
+	if (mem->validation_bits & CPER_MEM_VALID_PA)
+		printk("%s""physical_address: 0x%016llx\n",
+		       pfx, mem->physical_addr);
+	if (mem->validation_bits & CPER_MEM_VALID_PA_MASK)
+		printk("%s""physical_address_mask: 0x%016llx\n",
+		       pfx, mem->physical_addr_mask);
+	cper_mem_err_pack(mem, &cmem);
+	if (cper_mem_err_location(&cmem, rcd_decode_str))
+		printk("%s%s\n", pfx, rcd_decode_str);
+	if (mem->validation_bits & CPER_MEM_VALID_ERROR_TYPE) {
+		u8 etype = mem->error_type;
+		printk("%s""error_type: %d, %s\n", pfx, etype,
+		       cper_mem_err_type_str(etype));
+	}
+	if (cper_dimm_err_location(&cmem, rcd_decode_str))
+		printk("%s%s\n", pfx, rcd_decode_str);
+}
+
+static const char * const pcie_port_type_strs[] = {
+	"PCIe end point",
+	"legacy PCI end point",
+	"unknown",
+	"unknown",
+	"root port",
+	"upstream switch port",
+	"downstream switch port",
+	"PCIe to PCI/PCI-X bridge",
+	"PCI/PCI-X to PCIe bridge",
+	"root complex integrated endpoint device",
+	"root complex event collector",
+};
+
+static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie,
+			    const struct acpi_hest_generic_data *gdata)
+{
+	if (pcie->validation_bits & CPER_PCIE_VALID_PORT_TYPE)
+		printk("%s""port_type: %d, %s\n", pfx, pcie->port_type,
+		       pcie->port_type < ARRAY_SIZE(pcie_port_type_strs) ?
+		       pcie_port_type_strs[pcie->port_type] : "unknown");
+	if (pcie->validation_bits & CPER_PCIE_VALID_VERSION)
+		printk("%s""version: %d.%d\n", pfx,
+		       pcie->version.major, pcie->version.minor);
+	if (pcie->validation_bits & CPER_PCIE_VALID_COMMAND_STATUS)
+		printk("%s""command: 0x%04x, status: 0x%04x\n", pfx,
+		       pcie->command, pcie->status);
+	if (pcie->validation_bits & CPER_PCIE_VALID_DEVICE_ID) {
+		const __u8 *p;
+		printk("%s""device_id: %04x:%02x:%02x.%x\n", pfx,
+		       pcie->device_id.segment, pcie->device_id.bus,
+		       pcie->device_id.device, pcie->device_id.function);
+		printk("%s""slot: %d\n", pfx,
+		       pcie->device_id.slot >> CPER_PCIE_SLOT_SHIFT);
+		printk("%s""secondary_bus: 0x%02x\n", pfx,
+		       pcie->device_id.secondary_bus);
+		printk("%s""vendor_id: 0x%04x, device_id: 0x%04x\n", pfx,
+		       pcie->device_id.vendor_id, pcie->device_id.device_id);
+		p = pcie->device_id.class_code;
+		printk("%s""class_code: %02x%02x%02x\n", pfx, p[0], p[1], p[2]);
+	}
+	if (pcie->validation_bits & CPER_PCIE_VALID_SERIAL_NUMBER)
+		printk("%s""serial number: 0x%04x, 0x%04x\n", pfx,
+		       pcie->serial_number.lower, pcie->serial_number.upper);
+	if (pcie->validation_bits & CPER_PCIE_VALID_BRIDGE_CONTROL_STATUS)
+		printk(
+	"%s""bridge: secondary_status: 0x%04x, control: 0x%04x\n",
+	pfx, pcie->bridge.secondary_status, pcie->bridge.control);
+}
+
+static void cper_estatus_print_section(
+	const char *pfx, const struct acpi_hest_generic_data *gdata, int sec_no)
+{
+	uuid_le *sec_type = (uuid_le *)gdata->section_type;
+	__u16 severity;
+	char newpfx[64];
+
+	severity = gdata->error_severity;
+	printk("%s""Error %d, type: %s\n", pfx, sec_no,
+	       cper_severity_str(severity));
+	if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
+		printk("%s""fru_id: %pUl\n", pfx, (uuid_le *)gdata->fru_id);
+	if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
+		printk("%s""fru_text: %.20s\n", pfx, gdata->fru_text);
+
+	snprintf(newpfx, sizeof(newpfx), "%s%s", pfx, INDENT_SP);
+	if (!uuid_le_cmp(*sec_type, CPER_SEC_PROC_GENERIC)) {
+		struct cper_sec_proc_generic *proc_err = (void *)(gdata + 1);
+		printk("%s""section_type: general processor error\n", newpfx);
+		if (gdata->error_data_length >= sizeof(*proc_err))
+			cper_print_proc_generic(newpfx, proc_err);
+		else
+			goto err_section_too_small;
+	} else if (!uuid_le_cmp(*sec_type, CPER_SEC_PLATFORM_MEM)) {
+		struct cper_sec_mem_err *mem_err = (void *)(gdata + 1);
+		printk("%s""section_type: memory error\n", newpfx);
+		if (gdata->error_data_length >= sizeof(*mem_err))
+			cper_print_mem(newpfx, mem_err);
+		else
+			goto err_section_too_small;
+	} else if (!uuid_le_cmp(*sec_type, CPER_SEC_PCIE)) {
+		struct cper_sec_pcie *pcie = (void *)(gdata + 1);
+		printk("%s""section_type: PCIe error\n", newpfx);
+		if (gdata->error_data_length >= sizeof(*pcie))
+			cper_print_pcie(newpfx, pcie, gdata);
+		else
+			goto err_section_too_small;
+	} else
+		printk("%s""section type: unknown, %pUl\n", newpfx, sec_type);
+
+	return;
+
+err_section_too_small:
+	pr_err(FW_WARN "error section length is too small\n");
+}
+
+void cper_estatus_print(const char *pfx,
+			const struct acpi_hest_generic_status *estatus)
+{
+	struct acpi_hest_generic_data *gdata;
+	unsigned int data_len, gedata_len;
+	int sec_no = 0;
+	char newpfx[64];
+	__u16 severity;
+
+	severity = estatus->error_severity;
+	if (severity == CPER_SEV_CORRECTED)
+		printk("%s%s\n", pfx,
+		       "It has been corrected by h/w "
+		       "and requires no further action");
+	printk("%s""event severity: %s\n", pfx, cper_severity_str(severity));
+	data_len = estatus->data_length;
+	gdata = (struct acpi_hest_generic_data *)(estatus + 1);
+	snprintf(newpfx, sizeof(newpfx), "%s%s", pfx, INDENT_SP);
+	while (data_len >= sizeof(*gdata)) {
+		gedata_len = gdata->error_data_length;
+		cper_estatus_print_section(newpfx, gdata, sec_no);
+		data_len -= gedata_len + sizeof(*gdata);
+		gdata = (void *)(gdata + 1) + gedata_len;
+		sec_no++;
+	}
+}
+EXPORT_SYMBOL_GPL(cper_estatus_print);
+
+int cper_estatus_check_header(const struct acpi_hest_generic_status *estatus)
+{
+	if (estatus->data_length &&
+	    estatus->data_length < sizeof(struct acpi_hest_generic_data))
+		return -EINVAL;
+	if (estatus->raw_data_length &&
+	    estatus->raw_data_offset < sizeof(*estatus) + estatus->data_length)
+		return -EINVAL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cper_estatus_check_header);
+
+int cper_estatus_check(const struct acpi_hest_generic_status *estatus)
+{
+	struct acpi_hest_generic_data *gdata;
+	unsigned int data_len, gedata_len;
+	int rc;
+
+	rc = cper_estatus_check_header(estatus);
+	if (rc)
+		return rc;
+	data_len = estatus->data_length;
+	gdata = (struct acpi_hest_generic_data *)(estatus + 1);
+	while (data_len >= sizeof(*gdata)) {
+		gedata_len = gdata->error_data_length;
+		if (gedata_len > data_len - sizeof(*gdata))
+			return -EINVAL;
+		data_len -= gedata_len + sizeof(*gdata);
+		gdata = (void *)(gdata + 1) + gedata_len;
+	}
+	if (data_len)
+		return -EINVAL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cper_estatus_check);

drivers/firmware/efi/efi-pstore.c

@@ -0,0 +1,402 @@
+#include <linux/efi.h>
+#include <linux/module.h>
+#include <linux/pstore.h>
+#include <linux/slab.h>
+#include <linux/ucs2_string.h>
+
+#define DUMP_NAME_LEN 52
+
+static bool efivars_pstore_disable =
+	IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE);
+
+module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644);
+
+#define PSTORE_EFI_ATTRIBUTES \
+	(EFI_VARIABLE_NON_VOLATILE | \
+	 EFI_VARIABLE_BOOTSERVICE_ACCESS | \
+	 EFI_VARIABLE_RUNTIME_ACCESS)
+
+static int efi_pstore_open(struct pstore_info *psi)
+{
+	psi->data = NULL;
+	return 0;
+}
+
+static int efi_pstore_close(struct pstore_info *psi)
+{
+	psi->data = NULL;
+	return 0;
+}
+
+struct pstore_read_data {
+	u64 *id;
+	enum pstore_type_id *type;
+	int *count;
+	struct timespec *timespec;
+	bool *compressed;
+	char **buf;
+};
+
+static inline u64 generic_id(unsigned long timestamp,
+			     unsigned int part, int count)
+{
+	return ((u64) timestamp * 100 + part) * 1000 + count;
+}
+
+static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
+{
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	struct pstore_read_data *cb_data = data;
+	char name[DUMP_NAME_LEN], data_type;
+	int i;
+	int cnt;
+	unsigned int part;
+	unsigned long time, size;
+
+	if (efi_guidcmp(entry->var.VendorGuid, vendor))
+		return 0;
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		name[i] = entry->var.VariableName[i];
+
+	if (sscanf(name, "dump-type%u-%u-%d-%lu-%c",
+		   cb_data->type, &part, &cnt, &time, &data_type) == 5) {
+		*cb_data->id = generic_id(time, part, cnt);
+		*cb_data->count = cnt;
+		cb_data->timespec->tv_sec = time;
+		cb_data->timespec->tv_nsec = 0;
+		if (data_type == 'C')
+			*cb_data->compressed = true;
+		else
+			*cb_data->compressed = false;
+	} else if (sscanf(name, "dump-type%u-%u-%d-%lu",
+		   cb_data->type, &part, &cnt, &time) == 4) {
+		*cb_data->id = generic_id(time, part, cnt);
+		*cb_data->count = cnt;
+		cb_data->timespec->tv_sec = time;
+		cb_data->timespec->tv_nsec = 0;
+		*cb_data->compressed = false;
+	} else if (sscanf(name, "dump-type%u-%u-%lu",
+			  cb_data->type, &part, &time) == 3) {
+		/*
+		 * Check if an old format,
+		 * which doesn't support holding
+		 * multiple logs, remains.
+		 */
+		*cb_data->id = generic_id(time, part, 0);
+		*cb_data->count = 0;
+		cb_data->timespec->tv_sec = time;
+		cb_data->timespec->tv_nsec = 0;
+		*cb_data->compressed = false;
+	} else
+		return 0;
+
+	entry->var.DataSize = 1024;
+	__efivar_entry_get(entry, &entry->var.Attributes,
+			   &entry->var.DataSize, entry->var.Data);
+	size = entry->var.DataSize;
+	memcpy(*cb_data->buf, entry->var.Data,
+	       (size_t)min_t(unsigned long, EFIVARS_DATA_SIZE_MAX, size));
+
+	return size;
+}
+
+/**
+ * efi_pstore_scan_sysfs_enter
+ * @entry: scanning entry
+ * @next: next entry
+ * @head: list head
+ */
+static void efi_pstore_scan_sysfs_enter(struct efivar_entry *pos,
+					struct efivar_entry *next,
+					struct list_head *head)
+{
+	pos->scanning = true;
+	if (&next->list != head)
+		next->scanning = true;
+}
+
+/**
+ * __efi_pstore_scan_sysfs_exit
+ * @entry: deleting entry
+ * @turn_off_scanning: Check if a scanning flag should be turned off
+ */
+static inline void __efi_pstore_scan_sysfs_exit(struct efivar_entry *entry,
+						bool turn_off_scanning)
+{
+	if (entry->deleting) {
+		list_del(&entry->list);
+		efivar_entry_iter_end();
+		efivar_unregister(entry);
+		efivar_entry_iter_begin();
+	} else if (turn_off_scanning)
+		entry->scanning = false;
+}
+
+/**
+ * efi_pstore_scan_sysfs_exit
+ * @pos: scanning entry
+ * @next: next entry
+ * @head: list head
+ * @stop: a flag checking if scanning will stop
+ */
+static void efi_pstore_scan_sysfs_exit(struct efivar_entry *pos,
+				       struct efivar_entry *next,
+				       struct list_head *head, bool stop)
+{
+	__efi_pstore_scan_sysfs_exit(pos, true);
+	if (stop)
+		__efi_pstore_scan_sysfs_exit(next, &next->list != head);
+}
+
+/**
+ * efi_pstore_sysfs_entry_iter
+ *
+ * @data: function-specific data to pass to callback
+ * @pos: entry to begin iterating from
+ *
+ * You MUST call efivar_enter_iter_begin() before this function, and
+ * efivar_entry_iter_end() afterwards.
+ *
+ * It is possible to begin iteration from an arbitrary entry within
+ * the list by passing @pos. @pos is updated on return to point to
+ * the next entry of the last one passed to efi_pstore_read_func().
+ * To begin iterating from the beginning of the list @pos must be %NULL.
+ */
+static int efi_pstore_sysfs_entry_iter(void *data, struct efivar_entry **pos)
+{
+	struct efivar_entry *entry, *n;
+	struct list_head *head = &efivar_sysfs_list;
+	int size = 0;
+
+	if (!*pos) {
+		list_for_each_entry_safe(entry, n, head, list) {
+			efi_pstore_scan_sysfs_enter(entry, n, head);
+
+			size = efi_pstore_read_func(entry, data);
+			efi_pstore_scan_sysfs_exit(entry, n, head, size < 0);
+			if (size)
+				break;
+		}
+		*pos = n;
+		return size;
+	}
+
+	list_for_each_entry_safe_from((*pos), n, head, list) {
+		efi_pstore_scan_sysfs_enter((*pos), n, head);
+
+		size = efi_pstore_read_func((*pos), data);
+		efi_pstore_scan_sysfs_exit((*pos), n, head, size < 0);
+		if (size)
+			break;
+	}
+	*pos = n;
+	return size;
+}
+
+/**
+ * efi_pstore_read
+ *
+ * This function returns a size of NVRAM entry logged via efi_pstore_write().
+ * The meaning and behavior of efi_pstore/pstore are as below.
+ *
+ * size > 0: Got data of an entry logged via efi_pstore_write() successfully,
+ *           and pstore filesystem will continue reading subsequent entries.
+ * size == 0: Entry was not logged via efi_pstore_write(),
+ *            and efi_pstore driver will continue reading subsequent entries.
+ * size < 0: Failed to get data of entry logging via efi_pstore_write(),
+ *           and pstore will stop reading entry.
+ */
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+			       int *count, struct timespec *timespec,
+			       char **buf, bool *compressed,
+			       struct pstore_info *psi)
+{
+	struct pstore_read_data data;
+	ssize_t size;
+
+	data.id = id;
+	data.type = type;
+	data.count = count;
+	data.timespec = timespec;
+	data.compressed = compressed;
+	data.buf = buf;
+
+	*data.buf = kzalloc(EFIVARS_DATA_SIZE_MAX, GFP_KERNEL);
+	if (!*data.buf)
+		return -ENOMEM;
+
+	efivar_entry_iter_begin();
+	size = efi_pstore_sysfs_entry_iter(&data,
+					   (struct efivar_entry **)&psi->data);
+	efivar_entry_iter_end();
+	if (size <= 0)
+		kfree(*data.buf);
+	return size;
+}
+
+static int efi_pstore_write(enum pstore_type_id type,
+		enum kmsg_dump_reason reason, u64 *id,
+		unsigned int part, int count, bool compressed, size_t size,
+		struct pstore_info *psi)
+{
+	char name[DUMP_NAME_LEN];
+	efi_char16_t efi_name[DUMP_NAME_LEN];
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	int i, ret = 0;
+
+	sprintf(name, "dump-type%u-%u-%d-%lu-%c", type, part, count,
+		get_seconds(), compressed ? 'C' : 'D');
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		efi_name[i] = name[i];
+
+	efivar_entry_set_safe(efi_name, vendor, PSTORE_EFI_ATTRIBUTES,
+			      !pstore_cannot_block_path(reason),
+			      size, psi->buf);
+
+	if (reason == KMSG_DUMP_OOPS)
+		efivar_run_worker();
+
+	*id = part;
+	return ret;
+};
+
+struct pstore_erase_data {
+	u64 id;
+	enum pstore_type_id type;
+	int count;
+	struct timespec time;
+	efi_char16_t *name;
+};
+
+/*
+ * Clean up an entry with the same name
+ */
+static int efi_pstore_erase_func(struct efivar_entry *entry, void *data)
+{
+	struct pstore_erase_data *ed = data;
+	efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
+	efi_char16_t efi_name_old[DUMP_NAME_LEN];
+	efi_char16_t *efi_name = ed->name;
+	unsigned long ucs2_len = ucs2_strlen(ed->name);
+	char name_old[DUMP_NAME_LEN];
+	int i;
+
+	if (efi_guidcmp(entry->var.VendorGuid, vendor))
+		return 0;
+
+	if (ucs2_strncmp(entry->var.VariableName,
+			  efi_name, (size_t)ucs2_len)) {
+		/*
+		 * Check if an old format, which doesn't support
+		 * holding multiple logs, remains.
+		 */
+		sprintf(name_old, "dump-type%u-%u-%lu", ed->type,
+			(unsigned int)ed->id, ed->time.tv_sec);
+
+		for (i = 0; i < DUMP_NAME_LEN; i++)
+			efi_name_old[i] = name_old[i];
+
+		if (ucs2_strncmp(entry->var.VariableName, efi_name_old,
+				  ucs2_strlen(efi_name_old)))
+			return 0;
+	}
+
+	if (entry->scanning) {
+		/*
+		 * Skip deletion because this entry will be deleted
+		 * after scanning is completed.
+		 */
+		entry->deleting = true;
+	} else
+		list_del(&entry->list);
+
+	/* found */
+	__efivar_entry_delete(entry);
+
+	return 1;
+}
+
+static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
+			    struct timespec time, struct pstore_info *psi)
+{
+	struct pstore_erase_data edata;
+	struct efivar_entry *entry = NULL;
+	char name[DUMP_NAME_LEN];
+	efi_char16_t efi_name[DUMP_NAME_LEN];
+	int found, i;
+	unsigned int part;
+
+	do_div(id, 1000);
+	part = do_div(id, 100);
+	sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, time.tv_sec);
+
+	for (i = 0; i < DUMP_NAME_LEN; i++)
+		efi_name[i] = name[i];
+
+	edata.id = part;
+	edata.type = type;
+	edata.count = count;
+	edata.time = time;
+	edata.name = efi_name;
+
+	efivar_entry_iter_begin();
+	found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry);
+
+	if (found && !entry->scanning) {
+		efivar_entry_iter_end();
+		efivar_unregister(entry);
+	} else
+		efivar_entry_iter_end();
+
+	return 0;
+}
+
+static struct pstore_info efi_pstore_info = {
+	.owner		= THIS_MODULE,
+	.name		= "efi",
+	.flags		= PSTORE_FLAGS_FRAGILE,
+	.open		= efi_pstore_open,
+	.close		= efi_pstore_close,
+	.read		= efi_pstore_read,
+	.write		= efi_pstore_write,
+	.erase		= efi_pstore_erase,
+};
+
+static __init int efivars_pstore_init(void)
+{
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return 0;
+
+	if (!efivars_kobject())
+		return 0;
+
+	if (efivars_pstore_disable)
+		return 0;
+
+	efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL);
+	if (!efi_pstore_info.buf)
+		return -ENOMEM;
+
+	efi_pstore_info.bufsize = 1024;
+	spin_lock_init(&efi_pstore_info.buf_lock);
+
+	if (pstore_register(&efi_pstore_info)) {
+		kfree(efi_pstore_info.buf);
+		efi_pstore_info.buf = NULL;
+		efi_pstore_info.bufsize = 0;
+	}
+
+	return 0;
+}
+
+static __exit void efivars_pstore_exit(void)
+{
+}
+
+module_init(efivars_pstore_init);
+module_exit(efivars_pstore_exit);
+
+MODULE_DESCRIPTION("EFI variable backend for pstore");
+MODULE_LICENSE("GPL");

drivers/firmware/efi/efi.c

@@ -0,0 +1,504 @@
+/*
+ * efi.c - EFI subsystem
+ *
+ * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
+ * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
+ * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
+ *
+ * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
+ * allowing the efivarfs to be mounted or the efivars module to be loaded.
+ * The existance of /sys/firmware/efi may also be used by userspace to
+ * determine that the system supports EFI.
+ *
+ * This file is released under the GPLv2.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/efi.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+
+struct efi __read_mostly efi = {
+	.mps        = EFI_INVALID_TABLE_ADDR,
+	.acpi       = EFI_INVALID_TABLE_ADDR,
+	.acpi20     = EFI_INVALID_TABLE_ADDR,
+	.smbios     = EFI_INVALID_TABLE_ADDR,
+	.sal_systab = EFI_INVALID_TABLE_ADDR,
+	.boot_info  = EFI_INVALID_TABLE_ADDR,
+	.hcdp       = EFI_INVALID_TABLE_ADDR,
+	.uga        = EFI_INVALID_TABLE_ADDR,
+	.uv_systab  = EFI_INVALID_TABLE_ADDR,
+	.fw_vendor  = EFI_INVALID_TABLE_ADDR,
+	.runtime    = EFI_INVALID_TABLE_ADDR,
+	.config_table  = EFI_INVALID_TABLE_ADDR,
+};
+EXPORT_SYMBOL(efi);
+
+static bool disable_runtime;
+static int __init setup_noefi(char *arg)
+{
+	disable_runtime = true;
+	return 0;
+}
+early_param("noefi", setup_noefi);
+
+bool efi_runtime_disabled(void)
+{
+	return disable_runtime;
+}
+
+static int __init parse_efi_cmdline(char *str)
+{
+	if (parse_option_str(str, "noruntime"))
+		disable_runtime = true;
+
+	return 0;
+}
+early_param("efi", parse_efi_cmdline);
+
+static struct kobject *efi_kobj;
+static struct kobject *efivars_kobj;
+
+/*
+ * Let's not leave out systab information that snuck into
+ * the efivars driver
+ */
+static ssize_t systab_show(struct kobject *kobj,
+			   struct kobj_attribute *attr, char *buf)
+{
+	char *str = buf;
+
+	if (!kobj || !buf)
+		return -EINVAL;
+
+	if (efi.mps != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "MPS=0x%lx\n", efi.mps);
+	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
+	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
+	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
+	if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
+	if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
+	if (efi.uga != EFI_INVALID_TABLE_ADDR)
+		str += sprintf(str, "UGA=0x%lx\n", efi.uga);
+
+	return str - buf;
+}
+
+static struct kobj_attribute efi_attr_systab =
+			__ATTR(systab, 0400, systab_show, NULL);
+
+#define EFI_FIELD(var) efi.var
+
+#define EFI_ATTR_SHOW(name) \
+static ssize_t name##_show(struct kobject *kobj, \
+				struct kobj_attribute *attr, char *buf) \
+{ \
+	return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
+}
+
+EFI_ATTR_SHOW(fw_vendor);
+EFI_ATTR_SHOW(runtime);
+EFI_ATTR_SHOW(config_table);
+
+static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
+static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
+static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
+
+static struct attribute *efi_subsys_attrs[] = {
+	&efi_attr_systab.attr,
+	&efi_attr_fw_vendor.attr,
+	&efi_attr_runtime.attr,
+	&efi_attr_config_table.attr,
+	NULL,
+};
+
+static umode_t efi_attr_is_visible(struct kobject *kobj,
+				   struct attribute *attr, int n)
+{
+	if (attr == &efi_attr_fw_vendor.attr) {
+		if (efi_enabled(EFI_PARAVIRT) ||
+				efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
+			return 0;
+	} else if (attr == &efi_attr_runtime.attr) {
+		if (efi.runtime == EFI_INVALID_TABLE_ADDR)
+			return 0;
+	} else if (attr == &efi_attr_config_table.attr) {
+		if (efi.config_table == EFI_INVALID_TABLE_ADDR)
+			return 0;
+	}
+
+	return attr->mode;
+}
+
+static struct attribute_group efi_subsys_attr_group = {
+	.attrs = efi_subsys_attrs,
+	.is_visible = efi_attr_is_visible,
+};
+
+static struct efivars generic_efivars;
+static struct efivar_operations generic_ops;
+
+static int generic_ops_register(void)
+{
+	generic_ops.get_variable = efi.get_variable;
+	generic_ops.set_variable = efi.set_variable;
+	generic_ops.get_next_variable = efi.get_next_variable;
+	generic_ops.query_variable_store = efi_query_variable_store;
+
+	return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
+}
+
+static void generic_ops_unregister(void)
+{
+	efivars_unregister(&generic_efivars);
+}
+
+/*
+ * We register the efi subsystem with the firmware subsystem and the
+ * efivars subsystem with the efi subsystem, if the system was booted with
+ * EFI.
+ */
+static int __init efisubsys_init(void)
+{
+	int error;
+
+	if (!efi_enabled(EFI_BOOT))
+		return 0;
+
+	/* We register the efi directory at /sys/firmware/efi */
+	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
+	if (!efi_kobj) {
+		pr_err("efi: Firmware registration failed.\n");
+		return -ENOMEM;
+	}
+
+	error = generic_ops_register();
+	if (error)
+		goto err_put;
+
+	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
+	if (error) {
+		pr_err("efi: Sysfs attribute export failed with error %d.\n",
+		       error);
+		goto err_unregister;
+	}
+
+	error = efi_runtime_map_init(efi_kobj);
+	if (error)
+		goto err_remove_group;
+
+	/* and the standard mountpoint for efivarfs */
+	efivars_kobj = kobject_create_and_add("efivars", efi_kobj);
+	if (!efivars_kobj) {
+		pr_err("efivars: Subsystem registration failed.\n");
+		error = -ENOMEM;
+		goto err_remove_group;
+	}
+
+	return 0;
+
+err_remove_group:
+	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
+err_unregister:
+	generic_ops_unregister();
+err_put:
+	kobject_put(efi_kobj);
+	return error;
+}
+
+subsys_initcall(efisubsys_init);
+
+
+/*
+ * We can't ioremap data in EFI boot services RAM, because we've already mapped
+ * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
+ * callable after efi_enter_virtual_mode and before efi_free_boot_services.
+ */
+void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
+{
+	struct efi_memory_map *map;
+	void *p;
+	map = efi.memmap;
+	if (!map)
+		return NULL;
+	if (WARN_ON(!map->map))
+		return NULL;
+	for (p = map->map; p < map->map_end; p += map->desc_size) {
+		efi_memory_desc_t *md = p;
+		u64 size = md->num_pages << EFI_PAGE_SHIFT;
+		u64 end = md->phys_addr + size;
+		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+		    md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+		if (!md->virt_addr)
+			continue;
+		if (phys_addr >= md->phys_addr && phys_addr < end) {
+			phys_addr += md->virt_addr - md->phys_addr;
+			return (__force void __iomem *)(unsigned long)phys_addr;
+		}
+	}
+	return NULL;
+}
+
+static __initdata efi_config_table_type_t common_tables[] = {
+	{ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
+	{ACPI_TABLE_GUID, "ACPI", &efi.acpi},
+	{HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
+	{MPS_TABLE_GUID, "MPS", &efi.mps},
+	{SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
+	{SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
+	{UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
+	{NULL_GUID, NULL, NULL},
+};
+
+static __init int match_config_table(efi_guid_t *guid,
+				     unsigned long table,
+				     efi_config_table_type_t *table_types)
+{
+	u8 str[EFI_VARIABLE_GUID_LEN + 1];
+	int i;
+
+	if (table_types) {
+		efi_guid_unparse(guid, str);
+
+		for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
+			efi_guid_unparse(&table_types[i].guid, str);
+
+			if (!efi_guidcmp(*guid, table_types[i].guid)) {
+				*(table_types[i].ptr) = table;
+				pr_cont(" %s=0x%lx ",
+					table_types[i].name, table);
+				return 1;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int __init efi_config_init(efi_config_table_type_t *arch_tables)
+{
+	void *config_tables, *tablep;
+	int i, sz;
+
+	if (efi_enabled(EFI_64BIT))
+		sz = sizeof(efi_config_table_64_t);
+	else
+		sz = sizeof(efi_config_table_32_t);
+
+	/*
+	 * Let's see what config tables the firmware passed to us.
+	 */
+	config_tables = early_memremap(efi.systab->tables,
+				       efi.systab->nr_tables * sz);
+	if (config_tables == NULL) {
+		pr_err("Could not map Configuration table!\n");
+		return -ENOMEM;
+	}
+
+	tablep = config_tables;
+	pr_info("");
+	for (i = 0; i < efi.systab->nr_tables; i++) {
+		efi_guid_t guid;
+		unsigned long table;
+
+		if (efi_enabled(EFI_64BIT)) {
+			u64 table64;
+			guid = ((efi_config_table_64_t *)tablep)->guid;
+			table64 = ((efi_config_table_64_t *)tablep)->table;
+			table = table64;
+#ifndef CONFIG_64BIT
+			if (table64 >> 32) {
+				pr_cont("\n");
+				pr_err("Table located above 4GB, disabling EFI.\n");
+				early_memunmap(config_tables,
+					       efi.systab->nr_tables * sz);
+				return -EINVAL;
+			}
+#endif
+		} else {
+			guid = ((efi_config_table_32_t *)tablep)->guid;
+			table = ((efi_config_table_32_t *)tablep)->table;
+		}
+
+		if (!match_config_table(&guid, table, common_tables))
+			match_config_table(&guid, table, arch_tables);
+
+		tablep += sz;
+	}
+	pr_cont("\n");
+	early_memunmap(config_tables, efi.systab->nr_tables * sz);
+
+	set_bit(EFI_CONFIG_TABLES, &efi.flags);
+
+	return 0;
+}
+
+#ifdef CONFIG_EFI_VARS_MODULE
+static int __init efi_load_efivars(void)
+{
+	struct platform_device *pdev;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return 0;
+
+	pdev = platform_device_register_simple("efivars", 0, NULL, 0);
+	return IS_ERR(pdev) ? PTR_ERR(pdev) : 0;
+}
+device_initcall(efi_load_efivars);
+#endif
+
+#ifdef CONFIG_EFI_PARAMS_FROM_FDT
+
+#define UEFI_PARAM(name, prop, field)			   \
+	{						   \
+		{ name },				   \
+		{ prop },				   \
+		offsetof(struct efi_fdt_params, field),    \
+		FIELD_SIZEOF(struct efi_fdt_params, field) \
+	}
+
+static __initdata struct {
+	const char name[32];
+	const char propname[32];
+	int offset;
+	int size;
+} dt_params[] = {
+	UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
+	UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
+	UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
+	UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
+	UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
+};
+
+struct param_info {
+	int verbose;
+	int found;
+	void *params;
+};
+
+static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
+				       int depth, void *data)
+{
+	struct param_info *info = data;
+	const void *prop;
+	void *dest;
+	u64 val;
+	int i, len;
+
+	if (depth != 1 ||
+	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
+		prop = of_get_flat_dt_prop(node, dt_params[i].propname, &len);
+		if (!prop)
+			return 0;
+		dest = info->params + dt_params[i].offset;
+		info->found++;
+
+		val = of_read_number(prop, len / sizeof(u32));
+
+		if (dt_params[i].size == sizeof(u32))
+			*(u32 *)dest = val;
+		else
+			*(u64 *)dest = val;
+
+		if (info->verbose)
+			pr_info("  %s: 0x%0*llx\n", dt_params[i].name,
+				dt_params[i].size * 2, val);
+	}
+	return 1;
+}
+
+int __init efi_get_fdt_params(struct efi_fdt_params *params, int verbose)
+{
+	struct param_info info;
+	int ret;
+
+	pr_info("Getting EFI parameters from FDT:\n");
+
+	info.verbose = verbose;
+	info.found = 0;
+	info.params = params;
+
+	ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
+	if (!info.found)
+		pr_info("UEFI not found.\n");
+	else if (!ret)
+		pr_err("Can't find '%s' in device tree!\n",
+		       dt_params[info.found].name);
+
+	return ret;
+}
+#endif /* CONFIG_EFI_PARAMS_FROM_FDT */
+
+static __initdata char memory_type_name[][20] = {
+	"Reserved",
+	"Loader Code",
+	"Loader Data",
+	"Boot Code",
+	"Boot Data",
+	"Runtime Code",
+	"Runtime Data",
+	"Conventional Memory",
+	"Unusable Memory",
+	"ACPI Reclaim Memory",
+	"ACPI Memory NVS",
+	"Memory Mapped I/O",
+	"MMIO Port Space",
+	"PAL Code"
+};
+
+char * __init efi_md_typeattr_format(char *buf, size_t size,
+				     const efi_memory_desc_t *md)
+{
+	char *pos;
+	int type_len;
+	u64 attr;
+
+	pos = buf;
+	if (md->type >= ARRAY_SIZE(memory_type_name))
+		type_len = snprintf(pos, size, "[type=%u", md->type);
+	else
+		type_len = snprintf(pos, size, "[%-*s",
+				    (int)(sizeof(memory_type_name[0]) - 1),
+				    memory_type_name[md->type]);
+	if (type_len >= size)
+		return buf;
+
+	pos += type_len;
+	size -= type_len;
+
+	attr = md->attribute;
+	if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
+		     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_WP |
+		     EFI_MEMORY_RP | EFI_MEMORY_XP | EFI_MEMORY_RUNTIME))
+		snprintf(pos, size, "|attr=0x%016llx]",
+			 (unsigned long long)attr);
+	else
+		snprintf(pos, size, "|%3s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
+			 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
+			 attr & EFI_MEMORY_XP      ? "XP"  : "",
+			 attr & EFI_MEMORY_RP      ? "RP"  : "",
+			 attr & EFI_MEMORY_WP      ? "WP"  : "",
+			 attr & EFI_MEMORY_UCE     ? "UCE" : "",
+			 attr & EFI_MEMORY_WB      ? "WB"  : "",
+			 attr & EFI_MEMORY_WT      ? "WT"  : "",
+			 attr & EFI_MEMORY_WC      ? "WC"  : "",
+			 attr & EFI_MEMORY_UC      ? "UC"  : "");
+	return buf;
+}

drivers/firmware/efi/efivars.c

@@ -0,0 +1,755 @@
+/*
+ * Originally from efivars.c,
+ *
+ * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
+ * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
+ *
+ * This code takes all variables accessible from EFI runtime and
+ *  exports them via sysfs
+ *
+ *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Changelog:
+ *
+ *  17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
+ *   remove check for efi_enabled in exit
+ *   add MODULE_VERSION
+ *
+ *  26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
+ *   minor bug fixes
+ *
+ *  21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com)
+ *   converted driver to export variable information via sysfs
+ *   and moved to drivers/firmware directory
+ *   bumped revision number to v0.07 to reflect conversion & move
+ *
+ *  10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   fix locking per Peter Chubb's findings
+ *
+ *  25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_unparse()
+ *
+ *  12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com>
+ *   use list_for_each_safe when deleting vars.
+ *   remove ifdef CONFIG_SMP around include <linux/smp.h>
+ *   v0.04 release to linux-ia64@linuxia64.org
+ *
+ *  20 April 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   Moved vars from /proc/efi to /proc/efi/vars, and made
+ *   efi.c own the /proc/efi directory.
+ *   v0.03 release to linux-ia64@linuxia64.org
+ *
+ *  26 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   At the request of Stephane, moved ownership of /proc/efi
+ *   to efi.c, and now efivars lives under /proc/efi/vars.
+ *
+ *  12 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   Feedback received from Stephane Eranian incorporated.
+ *   efivar_write() checks copy_from_user() return value.
+ *   efivar_read/write() returns proper errno.
+ *   v0.02 release to linux-ia64@linuxia64.org
+ *
+ *  26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
+ *   v0.01 release to linux-ia64@linuxia64.org
+ */
+
+#include <linux/efi.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/ucs2_string.h>
+#include <linux/compat.h>
+
+#define EFIVARS_VERSION "0.08"
+#define EFIVARS_DATE "2004-May-17"
+
+MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
+MODULE_DESCRIPTION("sysfs interface to EFI Variables");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(EFIVARS_VERSION);
+MODULE_ALIAS("platform:efivars");
+
+LIST_HEAD(efivar_sysfs_list);
+EXPORT_SYMBOL_GPL(efivar_sysfs_list);
+
+static struct kset *efivars_kset;
+
+static struct bin_attribute *efivars_new_var;
+static struct bin_attribute *efivars_del_var;
+
+struct compat_efi_variable {
+	efi_char16_t  VariableName[EFI_VAR_NAME_LEN/sizeof(efi_char16_t)];
+	efi_guid_t    VendorGuid;
+	__u32         DataSize;
+	__u8          Data[1024];
+	__u32         Status;
+	__u32         Attributes;
+} __packed;
+
+struct efivar_attribute {
+	struct attribute attr;
+	ssize_t (*show) (struct efivar_entry *entry, char *buf);
+	ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
+};
+
+#define EFIVAR_ATTR(_name, _mode, _show, _store) \
+struct efivar_attribute efivar_attr_##_name = { \
+	.attr = {.name = __stringify(_name), .mode = _mode}, \
+	.show = _show, \
+	.store = _store, \
+};
+
+#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
+#define to_efivar_entry(obj)  container_of(obj, struct efivar_entry, kobj)
+
+/*
+ * Prototype for sysfs creation function
+ */
+static int
+efivar_create_sysfs_entry(struct efivar_entry *new_var);
+
+static ssize_t
+efivar_guid_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return 0;
+
+	efi_guid_unparse(&var->VendorGuid, str);
+	str += strlen(str);
+	str += sprintf(str, "\n");
+
+	return str - buf;
+}
+
+static ssize_t
+efivar_attr_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	if (var->Attributes & EFI_VARIABLE_NON_VOLATILE)
+		str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n");
+	if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS)
+		str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
+		str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
+		str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n");
+	if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS)
+		str += sprintf(str,
+			"EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n");
+	if (var->Attributes &
+			EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
+		str += sprintf(str,
+			"EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n");
+	if (var->Attributes & EFI_VARIABLE_APPEND_WRITE)
+		str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n");
+	return str - buf;
+}
+
+static ssize_t
+efivar_size_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	char *str = buf;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	str += sprintf(str, "0x%lx\n", var->DataSize);
+	return str - buf;
+}
+
+static ssize_t
+efivar_data_read(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+
+	if (!entry || !buf)
+		return -EINVAL;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
+		return -EIO;
+
+	memcpy(buf, var->Data, var->DataSize);
+	return var->DataSize;
+}
+
+static inline int
+sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor,
+	     unsigned long size, u32 attributes, u8 *data)
+{
+	/*
+	 * If only updating the variable data, then the name
+	 * and guid should remain the same
+	 */
+	if (memcmp(name, var->VariableName, sizeof(var->VariableName)) ||
+		efi_guidcmp(vendor, var->VendorGuid)) {
+		printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
+		return -EINVAL;
+	}
+
+	if ((size <= 0) || (attributes == 0)){
+		printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
+		return -EINVAL;
+	}
+
+	if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
+	    efivar_validate(name, data, size) == false) {
+		printk(KERN_ERR "efivars: Malformed variable content\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static inline bool is_compat(void)
+{
+	if (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())
+		return true;
+
+	return false;
+}
+
+static void
+copy_out_compat(struct efi_variable *dst, struct compat_efi_variable *src)
+{
+	memcpy(dst->VariableName, src->VariableName, EFI_VAR_NAME_LEN);
+	memcpy(dst->Data, src->Data, sizeof(src->Data));
+
+	dst->VendorGuid = src->VendorGuid;
+	dst->DataSize = src->DataSize;
+	dst->Attributes = src->Attributes;
+}
+
+/*
+ * We allow each variable to be edited via rewriting the
+ * entire efi variable structure.
+ */
+static ssize_t
+efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
+{
+	struct efi_variable *new_var, *var = &entry->var;
+	efi_char16_t *name;
+	unsigned long size;
+	efi_guid_t vendor;
+	u32 attributes;
+	u8 *data;
+	int err;
+
+	if (is_compat()) {
+		struct compat_efi_variable *compat;
+
+		if (count != sizeof(*compat))
+			return -EINVAL;
+
+		compat = (struct compat_efi_variable *)buf;
+		attributes = compat->Attributes;
+		vendor = compat->VendorGuid;
+		name = compat->VariableName;
+		size = compat->DataSize;
+		data = compat->Data;
+
+		err = sanity_check(var, name, vendor, size, attributes, data);
+		if (err)
+			return err;
+
+		copy_out_compat(&entry->var, compat);
+	} else {
+		if (count != sizeof(struct efi_variable))
+			return -EINVAL;
+
+		new_var = (struct efi_variable *)buf;
+
+		attributes = new_var->Attributes;
+		vendor = new_var->VendorGuid;
+		name = new_var->VariableName;
+		size = new_var->DataSize;
+		data = new_var->Data;
+
+		err = sanity_check(var, name, vendor, size, attributes, data);
+		if (err)
+			return err;
+
+		memcpy(&entry->var, new_var, count);
+	}
+
+	err = efivar_entry_set(entry, attributes, size, data, NULL);
+	if (err) {
+		printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err);
+		return -EIO;
+	}
+
+	return count;
+}
+
+static ssize_t
+efivar_show_raw(struct efivar_entry *entry, char *buf)
+{
+	struct efi_variable *var = &entry->var;
+	struct compat_efi_variable *compat;
+	size_t size;
+
+	if (!entry || !buf)
+		return 0;
+
+	var->DataSize = 1024;
+	if (efivar_entry_get(entry, &entry->var.Attributes,
+			     &entry->var.DataSize, entry->var.Data))
+		return -EIO;
+
+	if (is_compat()) {
+		compat = (struct compat_efi_variable *)buf;
+
+		size = sizeof(*compat);
+		memcpy(compat->VariableName, var->VariableName,
+			EFI_VAR_NAME_LEN);
+		memcpy(compat->Data, var->Data, sizeof(compat->Data));
+
+		compat->VendorGuid = var->VendorGuid;
+		compat->DataSize = var->DataSize;
+		compat->Attributes = var->Attributes;
+	} else {
+		size = sizeof(*var);
+		memcpy(buf, var, size);
+	}
+
+	return size;
+}
+
+/*
+ * Generic read/write functions that call the specific functions of
+ * the attributes...
+ */
+static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
+				char *buf)
+{
+	struct efivar_entry *var = to_efivar_entry(kobj);
+	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
+	ssize_t ret = -EIO;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (efivar_attr->show) {
+		ret = efivar_attr->show(var, buf);
+	}
+	return ret;
+}
+
+static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
+				const char *buf, size_t count)
+{
+	struct efivar_entry *var = to_efivar_entry(kobj);
+	struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
+	ssize_t ret = -EIO;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (efivar_attr->store)
+		ret = efivar_attr->store(var, buf, count);
+
+	return ret;
+}
+
+static const struct sysfs_ops efivar_attr_ops = {
+	.show = efivar_attr_show,
+	.store = efivar_attr_store,
+};
+
+static void efivar_release(struct kobject *kobj)
+{
+	struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj);
+	kfree(var);
+}
+
+static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL);
+static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL);
+static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL);
+static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL);
+static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw);
+
+static struct attribute *def_attrs[] = {
+	&efivar_attr_guid.attr,
+	&efivar_attr_size.attr,
+	&efivar_attr_attributes.attr,
+	&efivar_attr_data.attr,
+	&efivar_attr_raw_var.attr,
+	NULL,
+};
+
+static struct kobj_type efivar_ktype = {
+	.release = efivar_release,
+	.sysfs_ops = &efivar_attr_ops,
+	.default_attrs = def_attrs,
+};
+
+static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
+			     struct bin_attribute *bin_attr,
+			     char *buf, loff_t pos, size_t count)
+{
+	struct compat_efi_variable *compat = (struct compat_efi_variable *)buf;
+	struct efi_variable *new_var = (struct efi_variable *)buf;
+	struct efivar_entry *new_entry;
+	bool need_compat = is_compat();
+	efi_char16_t *name;
+	unsigned long size;
+	u32 attributes;
+	u8 *data;
+	int err;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (need_compat) {
+		if (count != sizeof(*compat))
+			return -EINVAL;
+
+		attributes = compat->Attributes;
+		name = compat->VariableName;
+		size = compat->DataSize;
+		data = compat->Data;
+	} else {
+		if (count != sizeof(*new_var))
+			return -EINVAL;
+
+		attributes = new_var->Attributes;
+		name = new_var->VariableName;
+		size = new_var->DataSize;
+		data = new_var->Data;
+	}
+
+	if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
+	    efivar_validate(name, data, size) == false) {
+		printk(KERN_ERR "efivars: Malformed variable content\n");
+		return -EINVAL;
+	}
+
+	new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL);
+	if (!new_entry)
+		return -ENOMEM;
+
+	if (need_compat)
+		copy_out_compat(&new_entry->var, compat);
+	else
+		memcpy(&new_entry->var, new_var, sizeof(*new_var));
+
+	err = efivar_entry_set(new_entry, attributes, size,
+			       data, &efivar_sysfs_list);
+	if (err) {
+		if (err == -EEXIST)
+			err = -EINVAL;
+		goto out;
+	}
+
+	if (efivar_create_sysfs_entry(new_entry)) {
+		printk(KERN_WARNING "efivars: failed to create sysfs entry.\n");
+		kfree(new_entry);
+	}
+	return count;
+
+out:
+	kfree(new_entry);
+	return err;
+}
+
+static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
+			     struct bin_attribute *bin_attr,
+			     char *buf, loff_t pos, size_t count)
+{
+	struct efi_variable *del_var = (struct efi_variable *)buf;
+	struct compat_efi_variable *compat;
+	struct efivar_entry *entry;
+	efi_char16_t *name;
+	efi_guid_t vendor;
+	int err = 0;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (is_compat()) {
+		if (count != sizeof(*compat))
+			return -EINVAL;
+
+		compat = (struct compat_efi_variable *)buf;
+		name = compat->VariableName;
+		vendor = compat->VendorGuid;
+	} else {
+		if (count != sizeof(*del_var))
+			return -EINVAL;
+
+		name = del_var->VariableName;
+		vendor = del_var->VendorGuid;
+	}
+
+	efivar_entry_iter_begin();
+	entry = efivar_entry_find(name, vendor, &efivar_sysfs_list, true);
+	if (!entry)
+		err = -EINVAL;
+	else if (__efivar_entry_delete(entry))
+		err = -EIO;
+
+	if (err) {
+		efivar_entry_iter_end();
+		return err;
+	}
+
+	if (!entry->scanning) {
+		efivar_entry_iter_end();
+		efivar_unregister(entry);
+	} else
+		efivar_entry_iter_end();
+
+	/* It's dead Jim.... */
+	return count;
+}
+
+/**
+ * efivar_create_sysfs_entry - create a new entry in sysfs
+ * @new_var: efivar entry to create
+ *
+ * Returns 1 on failure, 0 on success
+ */
+static int
+efivar_create_sysfs_entry(struct efivar_entry *new_var)
+{
+	int i, short_name_size;
+	char *short_name;
+	unsigned long variable_name_size;
+	efi_char16_t *variable_name;
+
+	variable_name = new_var->var.VariableName;
+	variable_name_size = ucs2_strlen(variable_name) * sizeof(efi_char16_t);
+
+	/*
+	 * Length of the variable bytes in ASCII, plus the '-' separator,
+	 * plus the GUID, plus trailing NUL
+	 */
+	short_name_size = variable_name_size / sizeof(efi_char16_t)
+				+ 1 + EFI_VARIABLE_GUID_LEN + 1;
+
+	short_name = kzalloc(short_name_size, GFP_KERNEL);
+
+	if (!short_name)
+		return 1;
+
+	/* Convert Unicode to normal chars (assume top bits are 0),
+	   ala UTF-8 */
+	for (i=0; i < (int)(variable_name_size / sizeof(efi_char16_t)); i++) {
+		short_name[i] = variable_name[i] & 0xFF;
+	}
+	/* This is ugly, but necessary to separate one vendor's
+	   private variables from another's.         */
+
+	*(short_name + strlen(short_name)) = '-';
+	efi_guid_unparse(&new_var->var.VendorGuid,
+			 short_name + strlen(short_name));
+
+	new_var->kobj.kset = efivars_kset;
+
+	i = kobject_init_and_add(&new_var->kobj, &efivar_ktype,
+				   NULL, "%s", short_name);
+	kfree(short_name);
+	if (i)
+		return 1;
+
+	kobject_uevent(&new_var->kobj, KOBJ_ADD);
+	efivar_entry_add(new_var, &efivar_sysfs_list);
+
+	return 0;
+}
+
+static int
+create_efivars_bin_attributes(void)
+{
+	struct bin_attribute *attr;
+	int error;
+
+	/* new_var */
+	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+	if (!attr)
+		return -ENOMEM;
+
+	attr->attr.name = "new_var";
+	attr->attr.mode = 0200;
+	attr->write = efivar_create;
+	efivars_new_var = attr;
+
+	/* del_var */
+	attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+	if (!attr) {
+		error = -ENOMEM;
+		goto out_free;
+	}
+	attr->attr.name = "del_var";
+	attr->attr.mode = 0200;
+	attr->write = efivar_delete;
+	efivars_del_var = attr;
+
+	sysfs_bin_attr_init(efivars_new_var);
+	sysfs_bin_attr_init(efivars_del_var);
+
+	/* Register */
+	error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var);
+	if (error) {
+		printk(KERN_ERR "efivars: unable to create new_var sysfs file"
+			" due to error %d\n", error);
+		goto out_free;
+	}
+
+	error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var);
+	if (error) {
+		printk(KERN_ERR "efivars: unable to create del_var sysfs file"
+			" due to error %d\n", error);
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
+		goto out_free;
+	}
+
+	return 0;
+out_free:
+	kfree(efivars_del_var);
+	efivars_del_var = NULL;
+	kfree(efivars_new_var);
+	efivars_new_var = NULL;
+	return error;
+}
+
+static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor,
+				     unsigned long name_size, void *data)
+{
+	struct efivar_entry *entry = data;
+
+	if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false))
+		return 0;
+
+	memcpy(entry->var.VariableName, name, name_size);
+	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
+
+	return 1;
+}
+
+static void efivar_update_sysfs_entries(struct work_struct *work)
+{
+	struct efivar_entry *entry;
+	int err;
+
+	/* Add new sysfs entries */
+	while (1) {
+		entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+		if (!entry)
+			return;
+
+		err = efivar_init(efivar_update_sysfs_entry, entry,
+				  true, false, &efivar_sysfs_list);
+		if (!err)
+			break;
+
+		efivar_create_sysfs_entry(entry);
+	}
+
+	kfree(entry);
+}
+
+static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor,
+				  unsigned long name_size, void *data)
+{
+	struct efivar_entry *entry;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	memcpy(entry->var.VariableName, name, name_size);
+	memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
+
+	efivar_create_sysfs_entry(entry);
+
+	return 0;
+}
+
+static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data)
+{
+	efivar_entry_remove(entry);
+	efivar_unregister(entry);
+	return 0;
+}
+
+static void efivars_sysfs_exit(void)
+{
+	/* Remove all entries and destroy */
+	__efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL);
+
+	if (efivars_new_var)
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
+	if (efivars_del_var)
+		sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var);
+	kfree(efivars_new_var);
+	kfree(efivars_del_var);
+	kset_unregister(efivars_kset);
+}
+
+int efivars_sysfs_init(void)
+{
+	struct kobject *parent_kobj = efivars_kobject();
+	int error = 0;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return -ENODEV;
+
+	/* No efivars has been registered yet */
+	if (!parent_kobj)
+		return 0;
+
+	printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
+	       EFIVARS_DATE);
+
+	efivars_kset = kset_create_and_add("vars", NULL, parent_kobj);
+	if (!efivars_kset) {
+		printk(KERN_ERR "efivars: Subsystem registration failed.\n");
+		return -ENOMEM;
+	}
+
+	efivar_init(efivars_sysfs_callback, NULL, false,
+		    true, &efivar_sysfs_list);
+
+	error = create_efivars_bin_attributes();
+	if (error) {
+		efivars_sysfs_exit();
+		return error;
+	}
+
+	INIT_WORK(&efivar_work, efivar_update_sysfs_entries);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(efivars_sysfs_init);
+
+module_init(efivars_sysfs_init);
+module_exit(efivars_sysfs_exit);

drivers/firmware/efi/libstub/Makefile

@@ -0,0 +1,26 @@
+#
+# The stub may be linked into the kernel proper or into a separate boot binary,
+# but in either case, it executes before the kernel does (with MMU disabled) so
+# things like ftrace and stack-protector are likely to cause trouble if left
+# enabled, even if doing so doesn't break the build.
+#
+cflags-$(CONFIG_X86_32)		:= -march=i386
+cflags-$(CONFIG_X86_64)		:= -mcmodel=small
+cflags-$(CONFIG_X86)		+= -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 \
+				   -fPIC -fno-strict-aliasing -mno-red-zone \
+				   -mno-mmx -mno-sse -DDISABLE_BRANCH_PROFILING
+
+cflags-$(CONFIG_ARM64)		:= $(subst -pg,,$(KBUILD_CFLAGS))
+cflags-$(CONFIG_ARM)		:= $(subst -pg,,$(KBUILD_CFLAGS)) \
+				   -fno-builtin -fpic -mno-single-pic-base
+
+KBUILD_CFLAGS			:= $(cflags-y) \
+				   $(call cc-option,-ffreestanding) \
+				   $(call cc-option,-fno-stack-protector)
+
+GCOV_PROFILE			:= n
+
+lib-y				:= efi-stub-helper.o
+lib-$(CONFIG_EFI_ARMSTUB)	+= arm-stub.o fdt.o
+
+CFLAGS_fdt.o			+= -I$(srctree)/scripts/dtc/libfdt/

drivers/firmware/efi/libstub/arm-stub.c

@@ -0,0 +1,288 @@
+/*
+ * EFI stub implementation that is shared by arm and arm64 architectures.
+ * This should be #included by the EFI stub implementation files.
+ *
+ * Copyright (C) 2013,2014 Linaro Limited
+ *     Roy Franz <roy.franz@linaro.org
+ * Copyright (C) 2013 Red Hat, Inc.
+ *     Mark Salter <msalter@redhat.com>
+ *
+ * This file is part of the Linux kernel, and is made available under the
+ * terms of the GNU General Public License version 2.
+ *
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+static int __init efi_secureboot_enabled(efi_system_table_t *sys_table_arg)
+{
+	static efi_guid_t const var_guid __initconst = EFI_GLOBAL_VARIABLE_GUID;
+	static efi_char16_t const var_name[] __initconst = {
+		'S', 'e', 'c', 'u', 'r', 'e', 'B', 'o', 'o', 't', 0 };
+
+	efi_get_variable_t *f_getvar = sys_table_arg->runtime->get_variable;
+	unsigned long size = sizeof(u8);
+	efi_status_t status;
+	u8 val;
+
+	status = f_getvar((efi_char16_t *)var_name, (efi_guid_t *)&var_guid,
+			  NULL, &size, &val);
+
+	switch (status) {
+	case EFI_SUCCESS:
+		return val;
+	case EFI_NOT_FOUND:
+		return 0;
+	default:
+		return 1;
+	}
+}
+
+efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg,
+			     void *__image, void **__fh)
+{
+	efi_file_io_interface_t *io;
+	efi_loaded_image_t *image = __image;
+	efi_file_handle_t *fh;
+	efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+	efi_status_t status;
+	void *handle = (void *)(unsigned long)image->device_handle;
+
+	status = sys_table_arg->boottime->handle_protocol(handle,
+				 &fs_proto, (void **)&io);
+	if (status != EFI_SUCCESS) {
+		efi_printk(sys_table_arg, "Failed to handle fs_proto\n");
+		return status;
+	}
+
+	status = io->open_volume(io, &fh);
+	if (status != EFI_SUCCESS)
+		efi_printk(sys_table_arg, "Failed to open volume\n");
+
+	*__fh = fh;
+	return status;
+}
+
+efi_status_t efi_file_close(void *handle)
+{
+	efi_file_handle_t *fh = handle;
+
+	return fh->close(handle);
+}
+
+efi_status_t
+efi_file_read(void *handle, unsigned long *size, void *addr)
+{
+	efi_file_handle_t *fh = handle;
+
+	return fh->read(handle, size, addr);
+}
+
+
+efi_status_t
+efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
+	      efi_char16_t *filename_16, void **handle, u64 *file_sz)
+{
+	efi_file_handle_t *h, *fh = __fh;
+	efi_file_info_t *info;
+	efi_status_t status;
+	efi_guid_t info_guid = EFI_FILE_INFO_ID;
+	unsigned long info_sz;
+
+	status = fh->open(fh, &h, filename_16, EFI_FILE_MODE_READ, (u64)0);
+	if (status != EFI_SUCCESS) {
+		efi_printk(sys_table_arg, "Failed to open file: ");
+		efi_char16_printk(sys_table_arg, filename_16);
+		efi_printk(sys_table_arg, "\n");
+		return status;
+	}
+
+	*handle = h;
+
+	info_sz = 0;
+	status = h->get_info(h, &info_guid, &info_sz, NULL);
+	if (status != EFI_BUFFER_TOO_SMALL) {
+		efi_printk(sys_table_arg, "Failed to get file info size\n");
+		return status;
+	}
+
+grow:
+	status = sys_table_arg->boottime->allocate_pool(EFI_LOADER_DATA,
+				 info_sz, (void **)&info);
+	if (status != EFI_SUCCESS) {
+		efi_printk(sys_table_arg, "Failed to alloc mem for file info\n");
+		return status;
+	}
+
+	status = h->get_info(h, &info_guid, &info_sz,
+						   info);
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		sys_table_arg->boottime->free_pool(info);
+		goto grow;
+	}
+
+	*file_sz = info->file_size;
+	sys_table_arg->boottime->free_pool(info);
+
+	if (status != EFI_SUCCESS)
+		efi_printk(sys_table_arg, "Failed to get initrd info\n");
+
+	return status;
+}
+
+
+
+void efi_char16_printk(efi_system_table_t *sys_table_arg,
+			      efi_char16_t *str)
+{
+	struct efi_simple_text_output_protocol *out;
+
+	out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out;
+	out->output_string(out, str);
+}
+
+
+/*
+ * This function handles the architcture specific differences between arm and
+ * arm64 regarding where the kernel image must be loaded and any memory that
+ * must be reserved. On failure it is required to free all
+ * all allocations it has made.
+ */
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
+				 unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 unsigned long dram_base,
+				 efi_loaded_image_t *image);
+/*
+ * EFI entry point for the arm/arm64 EFI stubs.  This is the entrypoint
+ * that is described in the PE/COFF header.  Most of the code is the same
+ * for both archictectures, with the arch-specific code provided in the
+ * handle_kernel_image() function.
+ */
+unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table,
+			       unsigned long *image_addr)
+{
+	efi_loaded_image_t *image;
+	efi_status_t status;
+	unsigned long image_size = 0;
+	unsigned long dram_base;
+	/* addr/point and size pairs for memory management*/
+	unsigned long initrd_addr;
+	u64 initrd_size = 0;
+	unsigned long fdt_addr = 0;  /* Original DTB */
+	u64 fdt_size = 0;  /* We don't get size from configuration table */
+	char *cmdline_ptr = NULL;
+	int cmdline_size = 0;
+	unsigned long new_fdt_addr;
+	efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
+	unsigned long reserve_addr = 0;
+	unsigned long reserve_size = 0;
+
+	/* Check if we were booted by the EFI firmware */
+	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+		goto fail;
+
+	pr_efi(sys_table, "Booting Linux Kernel...\n");
+
+	/*
+	 * Get a handle to the loaded image protocol.  This is used to get
+	 * information about the running image, such as size and the command
+	 * line.
+	 */
+	status = sys_table->boottime->handle_protocol(handle,
+					&loaded_image_proto, (void *)&image);
+	if (status != EFI_SUCCESS) {
+		pr_efi_err(sys_table, "Failed to get loaded image protocol\n");
+		goto fail;
+	}
+
+	dram_base = get_dram_base(sys_table);
+	if (dram_base == EFI_ERROR) {
+		pr_efi_err(sys_table, "Failed to find DRAM base\n");
+		goto fail;
+	}
+	status = handle_kernel_image(sys_table, image_addr, &image_size,
+				     &reserve_addr,
+				     &reserve_size,
+				     dram_base, image);
+	if (status != EFI_SUCCESS) {
+		pr_efi_err(sys_table, "Failed to relocate kernel\n");
+		goto fail;
+	}
+
+	/*
+	 * Get the command line from EFI, using the LOADED_IMAGE
+	 * protocol. We are going to copy the command line into the
+	 * device tree, so this can be allocated anywhere.
+	 */
+	cmdline_ptr = efi_convert_cmdline(sys_table, image, &cmdline_size);
+	if (!cmdline_ptr) {
+		pr_efi_err(sys_table, "getting command line via LOADED_IMAGE_PROTOCOL\n");
+		goto fail_free_image;
+	}
+
+	status = efi_parse_options(cmdline_ptr);
+	if (status != EFI_SUCCESS)
+		pr_efi_err(sys_table, "Failed to parse EFI cmdline options\n");
+
+	/*
+	 * Unauthenticated device tree data is a security hazard, so
+	 * ignore 'dtb=' unless UEFI Secure Boot is disabled.
+	 */
+	if (efi_secureboot_enabled(sys_table)) {
+		pr_efi(sys_table, "UEFI Secure Boot is enabled.\n");
+	} else {
+		status = handle_cmdline_files(sys_table, image, cmdline_ptr,
+					      "dtb=",
+					      ~0UL, (unsigned long *)&fdt_addr,
+					      (unsigned long *)&fdt_size);
+
+		if (status != EFI_SUCCESS) {
+			pr_efi_err(sys_table, "Failed to load device tree!\n");
+			goto fail_free_cmdline;
+		}
+	}
+	if (!fdt_addr)
+		/* Look for a device tree configuration table entry. */
+		fdt_addr = (uintptr_t)get_fdt(sys_table);
+
+	status = handle_cmdline_files(sys_table, image, cmdline_ptr,
+				      "initrd=", dram_base + SZ_512M,
+				      (unsigned long *)&initrd_addr,
+				      (unsigned long *)&initrd_size);
+	if (status != EFI_SUCCESS)
+		pr_efi_err(sys_table, "Failed initrd from command line!\n");
+
+	new_fdt_addr = fdt_addr;
+	status = allocate_new_fdt_and_exit_boot(sys_table, handle,
+				&new_fdt_addr, dram_base + MAX_FDT_OFFSET,
+				initrd_addr, initrd_size, cmdline_ptr,
+				fdt_addr, fdt_size);
+
+	/*
+	 * If all went well, we need to return the FDT address to the
+	 * calling function so it can be passed to kernel as part of
+	 * the kernel boot protocol.
+	 */
+	if (status == EFI_SUCCESS)
+		return new_fdt_addr;
+
+	pr_efi_err(sys_table, "Failed to update FDT and exit boot services\n");
+
+	efi_free(sys_table, initrd_size, initrd_addr);
+	efi_free(sys_table, fdt_size, fdt_addr);
+
+fail_free_cmdline:
+	efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr);
+
+fail_free_image:
+	efi_free(sys_table, image_size, *image_addr);
+	efi_free(sys_table, reserve_size, reserve_addr);
+fail:
+	return EFI_ERROR;
+}

drivers/firmware/efi/libstub/efi-stub-helper.c

@@ -0,0 +1,690 @@
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ *
+ * This file is part of the Linux kernel, and is made available
+ * under the terms of the GNU General Public License version 2.
+ *
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+/*
+ * Some firmware implementations have problems reading files in one go.
+ * A read chunk size of 1MB seems to work for most platforms.
+ *
+ * Unfortunately, reading files in chunks triggers *other* bugs on some
+ * platforms, so we provide a way to disable this workaround, which can
+ * be done by passing "efi=nochunk" on the EFI boot stub command line.
+ *
+ * If you experience issues with initrd images being corrupt it's worth
+ * trying efi=nochunk, but chunking is enabled by default because there
+ * are far more machines that require the workaround than those that
+ * break with it enabled.
+ */
+#define EFI_READ_CHUNK_SIZE	(1024 * 1024)
+
+static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;
+
+struct file_info {
+	efi_file_handle_t *handle;
+	u64 size;
+};
+
+void efi_printk(efi_system_table_t *sys_table_arg, char *str)
+{
+	char *s8;
+
+	for (s8 = str; *s8; s8++) {
+		efi_char16_t ch[2] = { 0 };
+
+		ch[0] = *s8;
+		if (*s8 == '\n') {
+			efi_char16_t nl[2] = { '\r', 0 };
+			efi_char16_printk(sys_table_arg, nl);
+		}
+
+		efi_char16_printk(sys_table_arg, ch);
+	}
+}
+
+efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg,
+				efi_memory_desc_t **map,
+				unsigned long *map_size,
+				unsigned long *desc_size,
+				u32 *desc_ver,
+				unsigned long *key_ptr)
+{
+	efi_memory_desc_t *m = NULL;
+	efi_status_t status;
+	unsigned long key;
+	u32 desc_version;
+
+	*map_size = sizeof(*m) * 32;
+again:
+	/*
+	 * Add an additional efi_memory_desc_t because we're doing an
+	 * allocation which may be in a new descriptor region.
+	 */
+	*map_size += sizeof(*m);
+	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
+				*map_size, (void **)&m);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	*desc_size = 0;
+	key = 0;
+	status = efi_call_early(get_memory_map, map_size, m,
+				&key, desc_size, &desc_version);
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		efi_call_early(free_pool, m);
+		goto again;
+	}
+
+	if (status != EFI_SUCCESS)
+		efi_call_early(free_pool, m);
+
+	if (key_ptr && status == EFI_SUCCESS)
+		*key_ptr = key;
+	if (desc_ver && status == EFI_SUCCESS)
+		*desc_ver = desc_version;
+
+fail:
+	*map = m;
+	return status;
+}
+
+
+unsigned long __init get_dram_base(efi_system_table_t *sys_table_arg)
+{
+	efi_status_t status;
+	unsigned long map_size;
+	unsigned long membase  = EFI_ERROR;
+	struct efi_memory_map map;
+	efi_memory_desc_t *md;
+
+	status = efi_get_memory_map(sys_table_arg, (efi_memory_desc_t **)&map.map,
+				    &map_size, &map.desc_size, NULL, NULL);
+	if (status != EFI_SUCCESS)
+		return membase;
+
+	map.map_end = map.map + map_size;
+
+	for_each_efi_memory_desc(&map, md)
+		if (md->attribute & EFI_MEMORY_WB)
+			if (membase > md->phys_addr)
+				membase = md->phys_addr;
+
+	efi_call_early(free_pool, map.map);
+
+	return membase;
+}
+
+/*
+ * Allocate at the highest possible address that is not above 'max'.
+ */
+efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
+			    unsigned long size, unsigned long align,
+			    unsigned long *addr, unsigned long max)
+{
+	unsigned long map_size, desc_size;
+	efi_memory_desc_t *map;
+	efi_status_t status;
+	unsigned long nr_pages;
+	u64 max_addr = 0;
+	int i;
+
+	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+				    NULL, NULL);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Enforce minimum alignment that EFI requires when requesting
+	 * a specific address.  We are doing page-based allocations,
+	 * so we must be aligned to a page.
+	 */
+	if (align < EFI_PAGE_SIZE)
+		align = EFI_PAGE_SIZE;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+again:
+	for (i = 0; i < map_size / desc_size; i++) {
+		efi_memory_desc_t *desc;
+		unsigned long m = (unsigned long)map;
+		u64 start, end;
+
+		desc = (efi_memory_desc_t *)(m + (i * desc_size));
+		if (desc->type != EFI_CONVENTIONAL_MEMORY)
+			continue;
+
+		if (desc->num_pages < nr_pages)
+			continue;
+
+		start = desc->phys_addr;
+		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+		if (end > max)
+			end = max;
+
+		if ((start + size) > end)
+			continue;
+
+		if (round_down(end - size, align) < start)
+			continue;
+
+		start = round_down(end - size, align);
+
+		/*
+		 * Don't allocate at 0x0. It will confuse code that
+		 * checks pointers against NULL.
+		 */
+		if (start == 0x0)
+			continue;
+
+		if (start > max_addr)
+			max_addr = start;
+	}
+
+	if (!max_addr)
+		status = EFI_NOT_FOUND;
+	else {
+		status = efi_call_early(allocate_pages,
+					EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+					nr_pages, &max_addr);
+		if (status != EFI_SUCCESS) {
+			max = max_addr;
+			max_addr = 0;
+			goto again;
+		}
+
+		*addr = max_addr;
+	}
+
+	efi_call_early(free_pool, map);
+fail:
+	return status;
+}
+
+/*
+ * Allocate at the lowest possible address.
+ */
+efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
+			   unsigned long size, unsigned long align,
+			   unsigned long *addr)
+{
+	unsigned long map_size, desc_size;
+	efi_memory_desc_t *map;
+	efi_status_t status;
+	unsigned long nr_pages;
+	int i;
+
+	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+				    NULL, NULL);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Enforce minimum alignment that EFI requires when requesting
+	 * a specific address.  We are doing page-based allocations,
+	 * so we must be aligned to a page.
+	 */
+	if (align < EFI_PAGE_SIZE)
+		align = EFI_PAGE_SIZE;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	for (i = 0; i < map_size / desc_size; i++) {
+		efi_memory_desc_t *desc;
+		unsigned long m = (unsigned long)map;
+		u64 start, end;
+
+		desc = (efi_memory_desc_t *)(m + (i * desc_size));
+
+		if (desc->type != EFI_CONVENTIONAL_MEMORY)
+			continue;
+
+		if (desc->num_pages < nr_pages)
+			continue;
+
+		start = desc->phys_addr;
+		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+		/*
+		 * Don't allocate at 0x0. It will confuse code that
+		 * checks pointers against NULL. Skip the first 8
+		 * bytes so we start at a nice even number.
+		 */
+		if (start == 0x0)
+			start += 8;
+
+		start = round_up(start, align);
+		if ((start + size) > end)
+			continue;
+
+		status = efi_call_early(allocate_pages,
+					EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+					nr_pages, &start);
+		if (status == EFI_SUCCESS) {
+			*addr = start;
+			break;
+		}
+	}
+
+	if (i == map_size / desc_size)
+		status = EFI_NOT_FOUND;
+
+	efi_call_early(free_pool, map);
+fail:
+	return status;
+}
+
+void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
+	      unsigned long addr)
+{
+	unsigned long nr_pages;
+
+	if (!size)
+		return;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	efi_call_early(free_pages, addr, nr_pages);
+}
+
+/*
+ * Parse the ASCII string 'cmdline' for EFI options, denoted by the efi=
+ * option, e.g. efi=nochunk.
+ *
+ * It should be noted that efi= is parsed in two very different
+ * environments, first in the early boot environment of the EFI boot
+ * stub, and subsequently during the kernel boot.
+ */
+efi_status_t efi_parse_options(char *cmdline)
+{
+	char *str;
+
+	/*
+	 * If no EFI parameters were specified on the cmdline we've got
+	 * nothing to do.
+	 */
+	str = strstr(cmdline, "efi=");
+	if (!str)
+		return EFI_SUCCESS;
+
+	/* Skip ahead to first argument */
+	str += strlen("efi=");
+
+	/*
+	 * Remember, because efi= is also used by the kernel we need to
+	 * skip over arguments we don't understand.
+	 */
+	while (*str) {
+		if (!strncmp(str, "nochunk", 7)) {
+			str += strlen("nochunk");
+			__chunk_size = -1UL;
+		}
+
+		/* Group words together, delimited by "," */
+		while (*str && *str != ',')
+			str++;
+
+		if (*str == ',')
+			str++;
+	}
+
+	return EFI_SUCCESS;
+}
+
+/*
+ * Check the cmdline for a LILO-style file= arguments.
+ *
+ * We only support loading a file from the same filesystem as
+ * the kernel image.
+ */
+efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg,
+				  efi_loaded_image_t *image,
+				  char *cmd_line, char *option_string,
+				  unsigned long max_addr,
+				  unsigned long *load_addr,
+				  unsigned long *load_size)
+{
+	struct file_info *files;
+	unsigned long file_addr;
+	u64 file_size_total;
+	efi_file_handle_t *fh = NULL;
+	efi_status_t status;
+	int nr_files;
+	char *str;
+	int i, j, k;
+
+	file_addr = 0;
+	file_size_total = 0;
+
+	str = cmd_line;
+
+	j = 0;			/* See close_handles */
+
+	if (!load_addr || !load_size)
+		return EFI_INVALID_PARAMETER;
+
+	*load_addr = 0;
+	*load_size = 0;
+
+	if (!str || !*str)
+		return EFI_SUCCESS;
+
+	for (nr_files = 0; *str; nr_files++) {
+		str = strstr(str, option_string);
+		if (!str)
+			break;
+
+		str += strlen(option_string);
+
+		/* Skip any leading slashes */
+		while (*str == '/' || *str == '\\')
+			str++;
+
+		while (*str && *str != ' ' && *str != '\n')
+			str++;
+	}
+
+	if (!nr_files)
+		return EFI_SUCCESS;
+
+	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
+				nr_files * sizeof(*files), (void **)&files);
+	if (status != EFI_SUCCESS) {
+		pr_efi_err(sys_table_arg, "Failed to alloc mem for file handle list\n");
+		goto fail;
+	}
+
+	str = cmd_line;
+	for (i = 0; i < nr_files; i++) {
+		struct file_info *file;
+		efi_char16_t filename_16[256];
+		efi_char16_t *p;
+
+		str = strstr(str, option_string);
+		if (!str)
+			break;
+
+		str += strlen(option_string);
+
+		file = &files[i];
+		p = filename_16;
+
+		/* Skip any leading slashes */
+		while (*str == '/' || *str == '\\')
+			str++;
+
+		while (*str && *str != ' ' && *str != '\n') {
+			if ((u8 *)p >= (u8 *)filename_16 + sizeof(filename_16))
+				break;
+
+			if (*str == '/') {
+				*p++ = '\\';
+				str++;
+			} else {
+				*p++ = *str++;
+			}
+		}
+
+		*p = '\0';
+
+		/* Only open the volume once. */
+		if (!i) {
+			status = efi_open_volume(sys_table_arg, image,
+						 (void **)&fh);
+			if (status != EFI_SUCCESS)
+				goto free_files;
+		}
+
+		status = efi_file_size(sys_table_arg, fh, filename_16,
+				       (void **)&file->handle, &file->size);
+		if (status != EFI_SUCCESS)
+			goto close_handles;
+
+		file_size_total += file->size;
+	}
+
+	if (file_size_total) {
+		unsigned long addr;
+
+		/*
+		 * Multiple files need to be at consecutive addresses in memory,
+		 * so allocate enough memory for all the files.  This is used
+		 * for loading multiple files.
+		 */
+		status = efi_high_alloc(sys_table_arg, file_size_total, 0x1000,
+				    &file_addr, max_addr);
+		if (status != EFI_SUCCESS) {
+			pr_efi_err(sys_table_arg, "Failed to alloc highmem for files\n");
+			goto close_handles;
+		}
+
+		/* We've run out of free low memory. */
+		if (file_addr > max_addr) {
+			pr_efi_err(sys_table_arg, "We've run out of free low memory\n");
+			status = EFI_INVALID_PARAMETER;
+			goto free_file_total;
+		}
+
+		addr = file_addr;
+		for (j = 0; j < nr_files; j++) {
+			unsigned long size;
+
+			size = files[j].size;
+			while (size) {
+				unsigned long chunksize;
+				if (size > __chunk_size)
+					chunksize = __chunk_size;
+				else
+					chunksize = size;
+
+				status = efi_file_read(files[j].handle,
+						       &chunksize,
+						       (void *)addr);
+				if (status != EFI_SUCCESS) {
+					pr_efi_err(sys_table_arg, "Failed to read file\n");
+					goto free_file_total;
+				}
+				addr += chunksize;
+				size -= chunksize;
+			}
+
+			efi_file_close(files[j].handle);
+		}
+
+	}
+
+	efi_call_early(free_pool, files);
+
+	*load_addr = file_addr;
+	*load_size = file_size_total;
+
+	return status;
+
+free_file_total:
+	efi_free(sys_table_arg, file_size_total, file_addr);
+
+close_handles:
+	for (k = j; k < i; k++)
+		efi_file_close(files[k].handle);
+free_files:
+	efi_call_early(free_pool, files);
+fail:
+	*load_addr = 0;
+	*load_size = 0;
+
+	return status;
+}
+/*
+ * Relocate a kernel image, either compressed or uncompressed.
+ * In the ARM64 case, all kernel images are currently
+ * uncompressed, and as such when we relocate it we need to
+ * allocate additional space for the BSS segment. Any low
+ * memory that this function should avoid needs to be
+ * unavailable in the EFI memory map, as if the preferred
+ * address is not available the lowest available address will
+ * be used.
+ */
+efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
+				 unsigned long *image_addr,
+				 unsigned long image_size,
+				 unsigned long alloc_size,
+				 unsigned long preferred_addr,
+				 unsigned long alignment)
+{
+	unsigned long cur_image_addr;
+	unsigned long new_addr = 0;
+	efi_status_t status;
+	unsigned long nr_pages;
+	efi_physical_addr_t efi_addr = preferred_addr;
+
+	if (!image_addr || !image_size || !alloc_size)
+		return EFI_INVALID_PARAMETER;
+	if (alloc_size < image_size)
+		return EFI_INVALID_PARAMETER;
+
+	cur_image_addr = *image_addr;
+
+	/*
+	 * The EFI firmware loader could have placed the kernel image
+	 * anywhere in memory, but the kernel has restrictions on the
+	 * max physical address it can run at.  Some architectures
+	 * also have a prefered address, so first try to relocate
+	 * to the preferred address.  If that fails, allocate as low
+	 * as possible while respecting the required alignment.
+	 */
+	nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	status = efi_call_early(allocate_pages,
+				EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+				nr_pages, &efi_addr);
+	new_addr = efi_addr;
+	/*
+	 * If preferred address allocation failed allocate as low as
+	 * possible.
+	 */
+	if (status != EFI_SUCCESS) {
+		status = efi_low_alloc(sys_table_arg, alloc_size, alignment,
+				       &new_addr);
+	}
+	if (status != EFI_SUCCESS) {
+		pr_efi_err(sys_table_arg, "Failed to allocate usable memory for kernel.\n");
+		return status;
+	}
+
+	/*
+	 * We know source/dest won't overlap since both memory ranges
+	 * have been allocated by UEFI, so we can safely use memcpy.
+	 */
+	memcpy((void *)new_addr, (void *)cur_image_addr, image_size);
+
+	/* Return the new address of the relocated image. */
+	*image_addr = new_addr;
+
+	return status;
+}
+
+/*
+ * Get the number of UTF-8 bytes corresponding to an UTF-16 character.
+ * This overestimates for surrogates, but that is okay.
+ */
+static int efi_utf8_bytes(u16 c)
+{
+	return 1 + (c >= 0x80) + (c >= 0x800);
+}
+
+/*
+ * Convert an UTF-16 string, not necessarily null terminated, to UTF-8.
+ */
+static u8 *efi_utf16_to_utf8(u8 *dst, const u16 *src, int n)
+{
+	unsigned int c;
+
+	while (n--) {
+		c = *src++;
+		if (n && c >= 0xd800 && c <= 0xdbff &&
+		    *src >= 0xdc00 && *src <= 0xdfff) {
+			c = 0x10000 + ((c & 0x3ff) << 10) + (*src & 0x3ff);
+			src++;
+			n--;
+		}
+		if (c >= 0xd800 && c <= 0xdfff)
+			c = 0xfffd; /* Unmatched surrogate */
+		if (c < 0x80) {
+			*dst++ = c;
+			continue;
+		}
+		if (c < 0x800) {
+			*dst++ = 0xc0 + (c >> 6);
+			goto t1;
+		}
+		if (c < 0x10000) {
+			*dst++ = 0xe0 + (c >> 12);
+			goto t2;
+		}
+		*dst++ = 0xf0 + (c >> 18);
+		*dst++ = 0x80 + ((c >> 12) & 0x3f);
+	t2:
+		*dst++ = 0x80 + ((c >> 6) & 0x3f);
+	t1:
+		*dst++ = 0x80 + (c & 0x3f);
+	}
+
+	return dst;
+}
+
+/*
+ * Convert the unicode UEFI command line to ASCII to pass to kernel.
+ * Size of memory allocated return in *cmd_line_len.
+ * Returns NULL on error.
+ */
+char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
+			  efi_loaded_image_t *image,
+			  int *cmd_line_len)
+{
+	const u16 *s2;
+	u8 *s1 = NULL;
+	unsigned long cmdline_addr = 0;
+	int load_options_chars = image->load_options_size / 2; /* UTF-16 */
+	const u16 *options = image->load_options;
+	int options_bytes = 0;  /* UTF-8 bytes */
+	int options_chars = 0;  /* UTF-16 chars */
+	efi_status_t status;
+	u16 zero = 0;
+
+	if (options) {
+		s2 = options;
+		while (*s2 && *s2 != '\n'
+		       && options_chars < load_options_chars) {
+			options_bytes += efi_utf8_bytes(*s2++);
+			options_chars++;
+		}
+	}
+
+	if (!options_chars) {
+		/* No command line options, so return empty string*/
+		options = &zero;
+	}
+
+	options_bytes++;	/* NUL termination */
+
+	status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr);
+	if (status != EFI_SUCCESS)
+		return NULL;
+
+	s1 = (u8 *)cmdline_addr;
+	s2 = (const u16 *)options;
+
+	s1 = efi_utf16_to_utf8(s1, s2, options_chars);
+	*s1 = '\0';
+
+	*cmd_line_len = options_bytes;
+	return (char *)cmdline_addr;
+}

drivers/firmware/efi/libstub/efistub.h

@@ -0,0 +1,42 @@
+
+#ifndef _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+#define _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+
+/* error code which can't be mistaken for valid address */
+#define EFI_ERROR	(~0UL)
+
+void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
+
+efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
+			     void **__fh);
+
+efi_status_t efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
+			   efi_char16_t *filename_16, void **handle,
+			   u64 *file_sz);
+
+efi_status_t efi_file_read(void *handle, unsigned long *size, void *addr);
+
+efi_status_t efi_file_close(void *handle);
+
+unsigned long get_dram_base(efi_system_table_t *sys_table_arg);
+
+efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
+			unsigned long orig_fdt_size,
+			void *fdt, int new_fdt_size, char *cmdline_ptr,
+			u64 initrd_addr, u64 initrd_size,
+			efi_memory_desc_t *memory_map,
+			unsigned long map_size, unsigned long desc_size,
+			u32 desc_ver);
+
+efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
+					    void *handle,
+					    unsigned long *new_fdt_addr,
+					    unsigned long max_addr,
+					    u64 initrd_addr, u64 initrd_size,
+					    char *cmdline_ptr,
+					    unsigned long fdt_addr,
+					    unsigned long fdt_size);
+
+void *get_fdt(efi_system_table_t *sys_table);
+
+#endif

drivers/firmware/efi/libstub/fdt.c

@@ -0,0 +1,287 @@
+/*
+ * FDT related Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2013 Linaro Limited; author Roy Franz
+ *
+ * This file is part of the Linux kernel, and is made available
+ * under the terms of the GNU General Public License version 2.
+ *
+ */
+
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+#include <asm/efi.h>
+
+efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
+			unsigned long orig_fdt_size,
+			void *fdt, int new_fdt_size, char *cmdline_ptr,
+			u64 initrd_addr, u64 initrd_size,
+			efi_memory_desc_t *memory_map,
+			unsigned long map_size, unsigned long desc_size,
+			u32 desc_ver)
+{
+	int node, prev, num_rsv;
+	int status;
+	u32 fdt_val32;
+	u64 fdt_val64;
+
+	/* Do some checks on provided FDT, if it exists*/
+	if (orig_fdt) {
+		if (fdt_check_header(orig_fdt)) {
+			pr_efi_err(sys_table, "Device Tree header not valid!\n");
+			return EFI_LOAD_ERROR;
+		}
+		/*
+		 * We don't get the size of the FDT if we get if from a
+		 * configuration table.
+		 */
+		if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {
+			pr_efi_err(sys_table, "Truncated device tree! foo!\n");
+			return EFI_LOAD_ERROR;
+		}
+	}
+
+	if (orig_fdt)
+		status = fdt_open_into(orig_fdt, fdt, new_fdt_size);
+	else
+		status = fdt_create_empty_tree(fdt, new_fdt_size);
+
+	if (status != 0)
+		goto fdt_set_fail;
+
+	/*
+	 * Delete any memory nodes present. We must delete nodes which
+	 * early_init_dt_scan_memory may try to use.
+	 */
+	prev = 0;
+	for (;;) {
+		const char *type;
+		int len;
+
+		node = fdt_next_node(fdt, prev, NULL);
+		if (node < 0)
+			break;
+
+		type = fdt_getprop(fdt, node, "device_type", &len);
+		if (type && strncmp(type, "memory", len) == 0) {
+			fdt_del_node(fdt, node);
+			continue;
+		}
+
+		prev = node;
+	}
+
+	/*
+	 * Delete all memory reserve map entries. When booting via UEFI,
+	 * kernel will use the UEFI memory map to find reserved regions.
+	 */
+	num_rsv = fdt_num_mem_rsv(fdt);
+	while (num_rsv-- > 0)
+		fdt_del_mem_rsv(fdt, num_rsv);
+
+	node = fdt_subnode_offset(fdt, 0, "chosen");
+	if (node < 0) {
+		node = fdt_add_subnode(fdt, 0, "chosen");
+		if (node < 0) {
+			status = node; /* node is error code when negative */
+			goto fdt_set_fail;
+		}
+	}
+
+	if ((cmdline_ptr != NULL) && (strlen(cmdline_ptr) > 0)) {
+		status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,
+				     strlen(cmdline_ptr) + 1);
+		if (status)
+			goto fdt_set_fail;
+	}
+
+	/* Set initrd address/end in device tree, if present */
+	if (initrd_size != 0) {
+		u64 initrd_image_end;
+		u64 initrd_image_start = cpu_to_fdt64(initrd_addr);
+
+		status = fdt_setprop(fdt, node, "linux,initrd-start",
+				     &initrd_image_start, sizeof(u64));
+		if (status)
+			goto fdt_set_fail;
+		initrd_image_end = cpu_to_fdt64(initrd_addr + initrd_size);
+		status = fdt_setprop(fdt, node, "linux,initrd-end",
+				     &initrd_image_end, sizeof(u64));
+		if (status)
+			goto fdt_set_fail;
+	}
+
+	/* Add FDT entries for EFI runtime services in chosen node. */
+	node = fdt_subnode_offset(fdt, 0, "chosen");
+	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)sys_table);
+	status = fdt_setprop(fdt, node, "linux,uefi-system-table",
+			     &fdt_val64, sizeof(fdt_val64));
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)memory_map);
+	status = fdt_setprop(fdt, node, "linux,uefi-mmap-start",
+			     &fdt_val64,  sizeof(fdt_val64));
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val32 = cpu_to_fdt32(map_size);
+	status = fdt_setprop(fdt, node, "linux,uefi-mmap-size",
+			     &fdt_val32,  sizeof(fdt_val32));
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val32 = cpu_to_fdt32(desc_size);
+	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-size",
+			     &fdt_val32, sizeof(fdt_val32));
+	if (status)
+		goto fdt_set_fail;
+
+	fdt_val32 = cpu_to_fdt32(desc_ver);
+	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-ver",
+			     &fdt_val32, sizeof(fdt_val32));
+	if (status)
+		goto fdt_set_fail;
+
+	/*
+	 * Add kernel version banner so stub/kernel match can be
+	 * verified.
+	 */
+	status = fdt_setprop_string(fdt, node, "linux,uefi-stub-kern-ver",
+			     linux_banner);
+	if (status)
+		goto fdt_set_fail;
+
+	return EFI_SUCCESS;
+
+fdt_set_fail:
+	if (status == -FDT_ERR_NOSPACE)
+		return EFI_BUFFER_TOO_SMALL;
+
+	return EFI_LOAD_ERROR;
+}
+
+#ifndef EFI_FDT_ALIGN
+#define EFI_FDT_ALIGN EFI_PAGE_SIZE
+#endif
+
+/*
+ * Allocate memory for a new FDT, then add EFI, commandline, and
+ * initrd related fields to the FDT.  This routine increases the
+ * FDT allocation size until the allocated memory is large
+ * enough.  EFI allocations are in EFI_PAGE_SIZE granules,
+ * which are fixed at 4K bytes, so in most cases the first
+ * allocation should succeed.
+ * EFI boot services are exited at the end of this function.
+ * There must be no allocations between the get_memory_map()
+ * call and the exit_boot_services() call, so the exiting of
+ * boot services is very tightly tied to the creation of the FDT
+ * with the final memory map in it.
+ */
+
+efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
+					    void *handle,
+					    unsigned long *new_fdt_addr,
+					    unsigned long max_addr,
+					    u64 initrd_addr, u64 initrd_size,
+					    char *cmdline_ptr,
+					    unsigned long fdt_addr,
+					    unsigned long fdt_size)
+{
+	unsigned long map_size, desc_size;
+	u32 desc_ver;
+	unsigned long mmap_key;
+	efi_memory_desc_t *memory_map;
+	unsigned long new_fdt_size;
+	efi_status_t status;
+
+	/*
+	 * Estimate size of new FDT, and allocate memory for it. We
+	 * will allocate a bigger buffer if this ends up being too
+	 * small, so a rough guess is OK here.
+	 */
+	new_fdt_size = fdt_size + EFI_PAGE_SIZE;
+	while (1) {
+		status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN,
+					new_fdt_addr, max_addr);
+		if (status != EFI_SUCCESS) {
+			pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n");
+			goto fail;
+		}
+
+		/*
+		 * Now that we have done our final memory allocation (and free)
+		 * we can get the memory map key  needed for
+		 * exit_boot_services().
+		 */
+		status = efi_get_memory_map(sys_table, &memory_map, &map_size,
+					    &desc_size, &desc_ver, &mmap_key);
+		if (status != EFI_SUCCESS)
+			goto fail_free_new_fdt;
+
+		status = update_fdt(sys_table,
+				    (void *)fdt_addr, fdt_size,
+				    (void *)*new_fdt_addr, new_fdt_size,
+				    cmdline_ptr, initrd_addr, initrd_size,
+				    memory_map, map_size, desc_size, desc_ver);
+
+		/* Succeeding the first time is the expected case. */
+		if (status == EFI_SUCCESS)
+			break;
+
+		if (status == EFI_BUFFER_TOO_SMALL) {
+			/*
+			 * We need to allocate more space for the new
+			 * device tree, so free existing buffer that is
+			 * too small.  Also free memory map, as we will need
+			 * to get new one that reflects the free/alloc we do
+			 * on the device tree buffer.
+			 */
+			efi_free(sys_table, new_fdt_size, *new_fdt_addr);
+			sys_table->boottime->free_pool(memory_map);
+			new_fdt_size += EFI_PAGE_SIZE;
+		} else {
+			pr_efi_err(sys_table, "Unable to constuct new device tree.\n");
+			goto fail_free_mmap;
+		}
+	}
+
+	/* Now we are ready to exit_boot_services.*/
+	status = sys_table->boottime->exit_boot_services(handle, mmap_key);
+
+
+	if (status == EFI_SUCCESS)
+		return status;
+
+	pr_efi_err(sys_table, "Exit boot services failed.\n");
+
+fail_free_mmap:
+	sys_table->boottime->free_pool(memory_map);
+
+fail_free_new_fdt:
+	efi_free(sys_table, new_fdt_size, *new_fdt_addr);
+
+fail:
+	return EFI_LOAD_ERROR;
+}
+
+void *get_fdt(efi_system_table_t *sys_table)
+{
+	efi_guid_t fdt_guid = DEVICE_TREE_GUID;
+	efi_config_table_t *tables;
+	void *fdt;
+	int i;
+
+	tables = (efi_config_table_t *) sys_table->tables;
+	fdt = NULL;
+
+	for (i = 0; i < sys_table->nr_tables; i++)
+		if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
+			fdt = (void *) tables[i].table;
+			break;
+	 }
+
+	return fdt;
+}

drivers/firmware/efi/reboot.c

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2014 Intel Corporation; author Matt Fleming
+ * Copyright (c) 2014 Red Hat, Inc., Mark Salter <msalter@redhat.com>
+ */
+#include <linux/efi.h>
+#include <linux/reboot.h>
+
+int efi_reboot_quirk_mode = -1;
+
+void efi_reboot(enum reboot_mode reboot_mode, const char *__unused)
+{
+	int efi_mode;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return;
+
+	switch (reboot_mode) {
+	case REBOOT_WARM:
+	case REBOOT_SOFT:
+		efi_mode = EFI_RESET_WARM;
+		break;
+	default:
+		efi_mode = EFI_RESET_COLD;
+		break;
+	}
+
+	/*
+	 * If a quirk forced an EFI reset mode, always use that.
+	 */
+	if (efi_reboot_quirk_mode != -1)
+		efi_mode = efi_reboot_quirk_mode;
+
+	efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL);
+}
+
+bool __weak efi_poweroff_required(void)
+{
+	return false;
+}
+
+static void efi_power_off(void)
+{
+	efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL);
+}
+
+static int __init efi_shutdown_init(void)
+{
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		return -ENODEV;
+
+	if (efi_poweroff_required())
+		pm_power_off = efi_power_off;
+
+	return 0;
+}
+late_initcall(efi_shutdown_init);

drivers/firmware/efi/runtime-map.c

@@ -0,0 +1,202 @@
+/*
+ * linux/drivers/efi/runtime-map.c
+ * Copyright (C) 2013 Red Hat, Inc., Dave Young <dyoung@redhat.com>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/efi.h>
+#include <linux/slab.h>
+
+#include <asm/setup.h>
+
+static void *efi_runtime_map;
+static int nr_efi_runtime_map;
+static u32 efi_memdesc_size;
+
+struct efi_runtime_map_entry {
+	efi_memory_desc_t md;
+	struct kobject kobj;   /* kobject for each entry */
+};
+
+static struct efi_runtime_map_entry **map_entries;
+
+struct map_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct efi_runtime_map_entry *entry, char *buf);
+};
+
+static inline struct map_attribute *to_map_attr(struct attribute *attr)
+{
+	return container_of(attr, struct map_attribute, attr);
+}
+
+static ssize_t type_show(struct efi_runtime_map_entry *entry, char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "0x%x\n", entry->md.type);
+}
+
+#define EFI_RUNTIME_FIELD(var) entry->md.var
+
+#define EFI_RUNTIME_U64_ATTR_SHOW(name) \
+static ssize_t name##_show(struct efi_runtime_map_entry *entry, char *buf) \
+{ \
+	return snprintf(buf, PAGE_SIZE, "0x%llx\n", EFI_RUNTIME_FIELD(name)); \
+}
+
+EFI_RUNTIME_U64_ATTR_SHOW(phys_addr);
+EFI_RUNTIME_U64_ATTR_SHOW(virt_addr);
+EFI_RUNTIME_U64_ATTR_SHOW(num_pages);
+EFI_RUNTIME_U64_ATTR_SHOW(attribute);
+
+static inline struct efi_runtime_map_entry *to_map_entry(struct kobject *kobj)
+{
+	return container_of(kobj, struct efi_runtime_map_entry, kobj);
+}
+
+static ssize_t map_attr_show(struct kobject *kobj, struct attribute *attr,
+			      char *buf)
+{
+	struct efi_runtime_map_entry *entry = to_map_entry(kobj);
+	struct map_attribute *map_attr = to_map_attr(attr);
+
+	return map_attr->show(entry, buf);
+}
+
+static struct map_attribute map_type_attr = __ATTR_RO(type);
+static struct map_attribute map_phys_addr_attr   = __ATTR_RO(phys_addr);
+static struct map_attribute map_virt_addr_attr  = __ATTR_RO(virt_addr);
+static struct map_attribute map_num_pages_attr  = __ATTR_RO(num_pages);
+static struct map_attribute map_attribute_attr  = __ATTR_RO(attribute);
+
+/*
+ * These are default attributes that are added for every memmap entry.
+ */
+static struct attribute *def_attrs[] = {
+	&map_type_attr.attr,
+	&map_phys_addr_attr.attr,
+	&map_virt_addr_attr.attr,
+	&map_num_pages_attr.attr,
+	&map_attribute_attr.attr,
+	NULL
+};
+
+static const struct sysfs_ops map_attr_ops = {
+	.show = map_attr_show,
+};
+
+static void map_release(struct kobject *kobj)
+{
+	struct efi_runtime_map_entry *entry;
+
+	entry = to_map_entry(kobj);
+	kfree(entry);
+}
+
+static struct kobj_type __refdata map_ktype = {
+	.sysfs_ops	= &map_attr_ops,
+	.default_attrs	= def_attrs,
+	.release	= map_release,
+};
+
+static struct kset *map_kset;
+
+static struct efi_runtime_map_entry *
+add_sysfs_runtime_map_entry(struct kobject *kobj, int nr)
+{
+	int ret;
+	struct efi_runtime_map_entry *entry;
+
+	if (!map_kset) {
+		map_kset = kset_create_and_add("runtime-map", NULL, kobj);
+		if (!map_kset)
+			return ERR_PTR(-ENOMEM);
+	}
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry) {
+		kset_unregister(map_kset);
+		return entry;
+	}
+
+	memcpy(&entry->md, efi_runtime_map + nr * efi_memdesc_size,
+	       sizeof(efi_memory_desc_t));
+
+	kobject_init(&entry->kobj, &map_ktype);
+	entry->kobj.kset = map_kset;
+	ret = kobject_add(&entry->kobj, NULL, "%d", nr);
+	if (ret) {
+		kobject_put(&entry->kobj);
+		kset_unregister(map_kset);
+		return ERR_PTR(ret);
+	}
+
+	return entry;
+}
+
+int efi_get_runtime_map_size(void)
+{
+	return nr_efi_runtime_map * efi_memdesc_size;
+}
+
+int efi_get_runtime_map_desc_size(void)
+{
+	return efi_memdesc_size;
+}
+
+int efi_runtime_map_copy(void *buf, size_t bufsz)
+{
+	size_t sz = efi_get_runtime_map_size();
+
+	if (sz > bufsz)
+		sz = bufsz;
+
+	memcpy(buf, efi_runtime_map, sz);
+	return 0;
+}
+
+void efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size)
+{
+	efi_runtime_map = map;
+	nr_efi_runtime_map = nr_entries;
+	efi_memdesc_size = desc_size;
+}
+
+int __init efi_runtime_map_init(struct kobject *efi_kobj)
+{
+	int i, j, ret = 0;
+	struct efi_runtime_map_entry *entry;
+
+	if (!efi_runtime_map)
+		return 0;
+
+	map_entries = kzalloc(nr_efi_runtime_map * sizeof(entry), GFP_KERNEL);
+	if (!map_entries) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < nr_efi_runtime_map; i++) {
+		entry = add_sysfs_runtime_map_entry(efi_kobj, i);
+		if (IS_ERR(entry)) {
+			ret = PTR_ERR(entry);
+			goto out_add_entry;
+		}
+		*(map_entries + i) = entry;
+	}
+
+	return 0;
+out_add_entry:
+	for (j = i - 1; j >= 0; j--) {
+		entry = *(map_entries + j);
+		kobject_put(&entry->kobj);
+	}
+	if (map_kset)
+		kset_unregister(map_kset);
+out:
+	return ret;
+}

drivers/firmware/efi/runtime-wrappers.c

@@ -0,0 +1,305 @@
+/*
+ * runtime-wrappers.c - Runtime Services function call wrappers
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * Split off from arch/x86/platform/efi/efi.c
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * Copyright (C) 2005-2008 Intel Co.
+ * Copyright (C) 2013 SuSE Labs
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/bug.h>
+#include <linux/efi.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <asm/efi.h>
+
+/*
+ * According to section 7.1 of the UEFI spec, Runtime Services are not fully
+ * reentrant, and there are particular combinations of calls that need to be
+ * serialized. (source: UEFI Specification v2.4A)
+ *
+ * Table 31. Rules for Reentry Into Runtime Services
+ * +------------------------------------+-------------------------------+
+ * | If previous call is busy in	| Forbidden to call		|
+ * +------------------------------------+-------------------------------+
+ * | Any				| SetVirtualAddressMap()	|
+ * +------------------------------------+-------------------------------+
+ * | ConvertPointer()			| ConvertPointer()		|
+ * +------------------------------------+-------------------------------+
+ * | SetVariable()			| ResetSystem()			|
+ * | UpdateCapsule()			|				|
+ * | SetTime()				|				|
+ * | SetWakeupTime()			|				|
+ * | GetNextHighMonotonicCount()	|				|
+ * +------------------------------------+-------------------------------+
+ * | GetVariable()			| GetVariable()			|
+ * | GetNextVariableName()		| GetNextVariableName()		|
+ * | SetVariable()			| SetVariable()			|
+ * | QueryVariableInfo()		| QueryVariableInfo()		|
+ * | UpdateCapsule()			| UpdateCapsule()		|
+ * | QueryCapsuleCapabilities()		| QueryCapsuleCapabilities()	|
+ * | GetNextHighMonotonicCount()	| GetNextHighMonotonicCount()	|
+ * +------------------------------------+-------------------------------+
+ * | GetTime()				| GetTime()			|
+ * | SetTime()				| SetTime()			|
+ * | GetWakeupTime()			| GetWakeupTime()		|
+ * | SetWakeupTime()			| SetWakeupTime()		|
+ * +------------------------------------+-------------------------------+
+ *
+ * Due to the fact that the EFI pstore may write to the variable store in
+ * interrupt context, we need to use a spinlock for at least the groups that
+ * contain SetVariable() and QueryVariableInfo(). That leaves little else, as
+ * none of the remaining functions are actually ever called at runtime.
+ * So let's just use a single spinlock to serialize all Runtime Services calls.
+ */
+static DEFINE_SPINLOCK(efi_runtime_lock);
+
+/*
+ * Some runtime services calls can be reentrant under NMI, even if the table
+ * above says they are not. (source: UEFI Specification v2.4A)
+ *
+ * Table 32. Functions that may be called after Machine Check, INIT and NMI
+ * +----------------------------+------------------------------------------+
+ * | Function			| Called after Machine Check, INIT and NMI |
+ * +----------------------------+------------------------------------------+
+ * | GetTime()			| Yes, even if previously busy.		   |
+ * | GetVariable()		| Yes, even if previously busy		   |
+ * | GetNextVariableName()	| Yes, even if previously busy		   |
+ * | QueryVariableInfo()	| Yes, even if previously busy		   |
+ * | SetVariable()		| Yes, even if previously busy		   |
+ * | UpdateCapsule()		| Yes, even if previously busy		   |
+ * | QueryCapsuleCapabilities()	| Yes, even if previously busy		   |
+ * | ResetSystem()		| Yes, even if previously busy		   |
+ * +----------------------------+------------------------------------------+
+ *
+ * In order to prevent deadlocks under NMI, the wrappers for these functions
+ * may only grab the efi_runtime_lock or rtc_lock spinlocks if !efi_in_nmi().
+ * However, not all of the services listed are reachable through NMI code paths,
+ * so the the special handling as suggested by the UEFI spec is only implemented
+ * for QueryVariableInfo() and SetVariable(), as these can be reached in NMI
+ * context through efi_pstore_write().
+ */
+
+/*
+ * As per commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock"),
+ * the EFI specification requires that callers of the time related runtime
+ * functions serialize with other CMOS accesses in the kernel, as the EFI time
+ * functions may choose to also use the legacy CMOS RTC.
+ */
+__weak DEFINE_SPINLOCK(rtc_lock);
+
+static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	spin_lock(&efi_runtime_lock);
+	status = efi_call_virt(get_time, tm, tc);
+	spin_unlock(&efi_runtime_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_set_time(efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	spin_lock(&efi_runtime_lock);
+	status = efi_call_virt(set_time, tm);
+	spin_unlock(&efi_runtime_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
+					     efi_bool_t *pending,
+					     efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	spin_lock(&efi_runtime_lock);
+	status = efi_call_virt(get_wakeup_time, enabled, pending, tm);
+	spin_unlock(&efi_runtime_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	spin_lock(&efi_runtime_lock);
+	status = efi_call_virt(set_wakeup_time, enabled, tm);
+	spin_unlock(&efi_runtime_lock);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 *attr,
+					  unsigned long *data_size,
+					  void *data)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(get_variable, name, vendor, attr, data_size,
+			       data);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
+					       efi_char16_t *name,
+					       efi_guid_t *vendor)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(get_next_variable, name_size, name, vendor);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_set_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 attr,
+					  unsigned long data_size,
+					  void *data)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(set_variable, name, vendor, attr, data_size,
+			       data);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static efi_status_t
+virt_efi_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
+				  u32 attr, unsigned long data_size,
+				  void *data)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
+		return EFI_NOT_READY;
+
+	status = efi_call_virt(set_variable, name, vendor, attr, data_size,
+			       data);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+
+static efi_status_t virt_efi_query_variable_info(u32 attr,
+						 u64 *storage_space,
+						 u64 *remaining_space,
+						 u64 *max_variable_size)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(query_variable_info, attr, storage_space,
+			       remaining_space, max_variable_size);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(get_next_high_mono_count, count);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static void virt_efi_reset_system(int reset_type,
+				  efi_status_t status,
+				  unsigned long data_size,
+				  efi_char16_t *data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	__efi_call_virt(reset_system, reset_type, status, data_size, data);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+}
+
+static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
+					    unsigned long count,
+					    unsigned long sg_list)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(update_capsule, capsules, count, sg_list);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
+						unsigned long count,
+						u64 *max_size,
+						int *reset_type)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	spin_lock_irqsave(&efi_runtime_lock, flags);
+	status = efi_call_virt(query_capsule_caps, capsules, count, max_size,
+			       reset_type);
+	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	return status;
+}
+
+void efi_native_runtime_setup(void)
+{
+	efi.get_time = virt_efi_get_time;
+	efi.set_time = virt_efi_set_time;
+	efi.get_wakeup_time = virt_efi_get_wakeup_time;
+	efi.set_wakeup_time = virt_efi_set_wakeup_time;
+	efi.get_variable = virt_efi_get_variable;
+	efi.get_next_variable = virt_efi_get_next_variable;
+	efi.set_variable = virt_efi_set_variable;
+	efi.set_variable_nonblocking = virt_efi_set_variable_nonblocking;
+	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
+	efi.reset_system = virt_efi_reset_system;
+	efi.query_variable_info = virt_efi_query_variable_info;
+	efi.update_capsule = virt_efi_update_capsule;
+	efi.query_capsule_caps = virt_efi_query_capsule_caps;
+}