Fixed MTP to work with TWRP

drivers/tty/hvc/Kconfig

@@ -0,0 +1,124 @@
+if TTY
+
+config HVC_DRIVER
+	bool
+	help
+	  Generic "hypervisor virtual console" infrastructure for various
+	  hypervisors (pSeries, iSeries, Xen, lguest).
+	  It will automatically be selected if one of the back-end console drivers
+	  is selected.
+
+config HVC_IRQ
+	bool
+
+config HVC_CONSOLE
+	bool "pSeries Hypervisor Virtual Console support"
+	depends on PPC_PSERIES
+	select HVC_DRIVER
+	select HVC_IRQ
+	help
+	  pSeries machines when partitioned support a hypervisor virtual
+	  console. This driver allows each pSeries partition to have a console
+	  which is accessed via the HMC.
+
+config HVC_OLD_HVSI
+	bool "Old driver for pSeries serial port (/dev/hvsi*)"
+	depends on HVC_CONSOLE
+	default n
+
+config HVC_OPAL
+	bool "OPAL Console support"
+	depends on PPC_POWERNV
+	select HVC_DRIVER
+	select HVC_IRQ
+	default y
+	help
+	  PowerNV machines running under OPAL need that driver to get a console
+
+config HVC_RTAS
+	bool "IBM RTAS Console support"
+	depends on PPC_RTAS
+	select HVC_DRIVER
+	help
+	  IBM Console device driver which makes use of RTAS
+
+config HVC_BEAT
+	bool "Toshiba's Beat Hypervisor Console support"
+	depends on PPC_CELLEB
+	select HVC_DRIVER
+	help
+	  Toshiba's Cell Reference Set Beat Console device driver
+
+config HVC_IUCV
+	bool "z/VM IUCV Hypervisor console support (VM only)"
+	depends on S390
+	select HVC_DRIVER
+	select IUCV
+	default y
+	help
+	  This driver provides a Hypervisor console (HVC) back-end to access
+	  a Linux (console) terminal via a z/VM IUCV communication path.
+
+config HVC_XEN
+	bool "Xen Hypervisor Console support"
+	depends on XEN
+	select HVC_DRIVER
+	select HVC_IRQ
+	default y
+	help
+	  Xen virtual console device driver
+
+config HVC_XEN_FRONTEND
+	bool "Xen Hypervisor Multiple Consoles support"
+	depends on HVC_XEN
+	select XEN_XENBUS_FRONTEND
+	default y
+	help
+	  Xen driver for secondary virtual consoles
+
+config HVC_UDBG
+       bool "udbg based fake hypervisor console"
+       depends on PPC
+       select HVC_DRIVER
+       default n
+       help
+         This is meant to be used during HW bring up or debugging when
+	 no other console mechanism exist but udbg, to get you a quick
+	 console for userspace. Do NOT enable in production kernels. 
+
+config HVC_DCC
+       bool "ARM JTAG DCC console"
+       depends on ARM
+       select HVC_DRIVER
+       help
+         This console uses the JTAG DCC on ARM to create a console under the HVC
+	 driver. This console is used through a JTAG only on ARM. If you don't have
+	 a JTAG then you probably don't want this option.
+
+config HVC_BFIN_JTAG
+	bool "Blackfin JTAG console"
+	depends on BLACKFIN
+	select HVC_DRIVER
+	help
+	 This console uses the Blackfin JTAG to create a console under the
+	 the HVC driver.  If you don't have JTAG, then you probably don't
+	 want this option.
+
+config HVCS
+	tristate "IBM Hypervisor Virtual Console Server support"
+	depends on PPC_PSERIES && HVC_CONSOLE
+	help
+	  Partitionable IBM Power5 ppc64 machines allow hosting of
+	  firmware virtual consoles from one Linux partition by
+	  another Linux partition.  This driver allows console data
+	  from Linux partitions to be accessed through TTY device
+	  interfaces in the device tree of a Linux partition running
+	  this driver.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called hvcs.  Additionally, this module
+	  will depend on arch specific APIs exported from hvcserver.ko
+	  which will also be compiled when this driver is built as a
+	  module.
+
+endif # TTY

drivers/tty/hvc/Makefile

@@ -0,0 +1,14 @@
+obj-$(CONFIG_HVC_CONSOLE)	+= hvc_vio.o hvsi_lib.o
+obj-$(CONFIG_HVC_OPAL)		+= hvc_opal.o hvsi_lib.o
+obj-$(CONFIG_HVC_OLD_HVSI)	+= hvsi.o
+obj-$(CONFIG_HVC_RTAS)		+= hvc_rtas.o
+obj-$(CONFIG_HVC_TILE)		+= hvc_tile.o
+obj-$(CONFIG_HVC_DCC)		+= hvc_dcc.o
+obj-$(CONFIG_HVC_BEAT)		+= hvc_beat.o
+obj-$(CONFIG_HVC_DRIVER)	+= hvc_console.o
+obj-$(CONFIG_HVC_IRQ)		+= hvc_irq.o
+obj-$(CONFIG_HVC_XEN)		+= hvc_xen.o
+obj-$(CONFIG_HVC_IUCV)		+= hvc_iucv.o
+obj-$(CONFIG_HVC_UDBG)		+= hvc_udbg.o
+obj-$(CONFIG_HVC_BFIN_JTAG)	+= hvc_bfin_jtag.o
+obj-$(CONFIG_HVCS)		+= hvcs.o

drivers/tty/hvc/hvc_beat.c

@@ -0,0 +1,134 @@
+/*
+ * Beat hypervisor console driver
+ *
+ * (C) Copyright 2006 TOSHIBA CORPORATION
+ *
+ * This code is based on drivers/char/hvc_rtas.c:
+ * (C) Copyright IBM Corporation 2001-2005
+ * (C) Copyright Red Hat, Inc. 2005
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/console.h>
+#include <asm/prom.h>
+#include <asm/hvconsole.h>
+#include <asm/firmware.h>
+
+#include "hvc_console.h"
+
+extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
+extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);
+
+struct hvc_struct *hvc_beat_dev = NULL;
+
+/* bug: only one queue is available regardless of vtermno */
+static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
+{
+	static unsigned char q[sizeof(unsigned long) * 2]
+		__attribute__((aligned(sizeof(unsigned long))));
+	static int qlen = 0;
+	u64 got;
+
+again:
+	if (qlen) {
+		if (qlen > cnt) {
+			memcpy(buf, q, cnt);
+			qlen -= cnt;
+			memmove(q + cnt, q, qlen);
+			return cnt;
+		} else {	/* qlen <= cnt */
+			int	r;
+
+			memcpy(buf, q, qlen);
+			r = qlen;
+			qlen = 0;
+			return r;
+		}
+	}
+	if (beat_get_term_char(vtermno, &got,
+		((u64 *)q), ((u64 *)q) + 1) == 0) {
+		qlen = got;
+		goto again;
+	}
+	return 0;
+}
+
+static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
+{
+	unsigned long kb[2];
+	int rest, nlen;
+
+	for (rest = cnt; rest > 0; rest -= nlen) {
+		nlen = (rest > 16) ? 16 : rest;
+		memcpy(kb, buf, nlen);
+		beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
+		buf += nlen;
+	}
+	return cnt;
+}
+
+static const struct hv_ops hvc_beat_get_put_ops = {
+	.get_chars = hvc_beat_get_chars,
+	.put_chars = hvc_beat_put_chars,
+};
+
+static int hvc_beat_useit = 1;
+
+static int hvc_beat_config(char *p)
+{
+	hvc_beat_useit = simple_strtoul(p, NULL, 0);
+	return 0;
+}
+
+static int __init hvc_beat_console_init(void)
+{
+	if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
+		hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
+	}
+	return 0;
+}
+
+/* temp */
+static int __init hvc_beat_init(void)
+{
+	struct hvc_struct *hp;
+
+	if (!firmware_has_feature(FW_FEATURE_BEAT))
+		return -ENODEV;
+
+	hp = hvc_alloc(0, 0, &hvc_beat_get_put_ops, 16);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+	hvc_beat_dev = hp;
+	return 0;
+}
+
+static void __exit hvc_beat_exit(void)
+{
+	if (hvc_beat_dev)
+		hvc_remove(hvc_beat_dev);
+}
+
+module_init(hvc_beat_init);
+module_exit(hvc_beat_exit);
+
+__setup("hvc_beat=", hvc_beat_config);
+
+console_initcall(hvc_beat_console_init);

drivers/tty/hvc/hvc_bfin_jtag.c

@@ -0,0 +1,105 @@
+/*
+ * Console via Blackfin JTAG Communication
+ *
+ * Copyright 2008-2011 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include "hvc_console.h"
+
+/* See the Debug/Emulation chapter in the HRM */
+#define EMUDOF   0x00000001	/* EMUDAT_OUT full & valid */
+#define EMUDIF   0x00000002	/* EMUDAT_IN full & valid */
+#define EMUDOOVF 0x00000004	/* EMUDAT_OUT overflow */
+#define EMUDIOVF 0x00000008	/* EMUDAT_IN overflow */
+
+/* Helper functions to glue the register API to simple C operations */
+static inline uint32_t bfin_write_emudat(uint32_t emudat)
+{
+	__asm__ __volatile__("emudat = %0;" : : "d"(emudat));
+	return emudat;
+}
+
+static inline uint32_t bfin_read_emudat(void)
+{
+	uint32_t emudat;
+	__asm__ __volatile__("%0 = emudat;" : "=d"(emudat));
+	return emudat;
+}
+
+/* Send data to the host */
+static int hvc_bfin_put_chars(uint32_t vt, const char *buf, int count)
+{
+	static uint32_t outbound_len;
+	uint32_t emudat;
+	int ret;
+
+	if (bfin_read_DBGSTAT() & EMUDOF)
+		return 0;
+
+	if (!outbound_len) {
+		outbound_len = count;
+		bfin_write_emudat(outbound_len);
+		return 0;
+	}
+
+	ret = min(outbound_len, (uint32_t)4);
+	memcpy(&emudat, buf, ret);
+	bfin_write_emudat(emudat);
+	outbound_len -= ret;
+
+	return ret;
+}
+
+/* Receive data from the host */
+static int hvc_bfin_get_chars(uint32_t vt, char *buf, int count)
+{
+	static uint32_t inbound_len;
+	uint32_t emudat;
+	int ret;
+
+	if (!(bfin_read_DBGSTAT() & EMUDIF))
+		return 0;
+	emudat = bfin_read_emudat();
+
+	if (!inbound_len) {
+		inbound_len = emudat;
+		return 0;
+	}
+
+	ret = min(inbound_len, (uint32_t)4);
+	memcpy(buf, &emudat, ret);
+	inbound_len -= ret;
+
+	return ret;
+}
+
+/* Glue the HVC layers to the Blackfin layers */
+static const struct hv_ops hvc_bfin_get_put_ops = {
+	.get_chars = hvc_bfin_get_chars,
+	.put_chars = hvc_bfin_put_chars,
+};
+
+static int __init hvc_bfin_console_init(void)
+{
+	hvc_instantiate(0, 0, &hvc_bfin_get_put_ops);
+	return 0;
+}
+console_initcall(hvc_bfin_console_init);
+
+static int __init hvc_bfin_init(void)
+{
+	hvc_alloc(0, 0, &hvc_bfin_get_put_ops, 128);
+	return 0;
+}
+device_initcall(hvc_bfin_init);

drivers/tty/hvc/hvc_console.h

@@ -0,0 +1,124 @@
+/*
+ * hvc_console.h
+ * Copyright (C) 2005 IBM Corporation
+ *
+ * Author(s):
+ * 	Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * hvc_console header information:
+ *      moved here from arch/powerpc/include/asm/hvconsole.h
+ *      and drivers/char/hvc_console.c
+ *
+ * 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
+ */
+
+#ifndef HVC_CONSOLE_H
+#define HVC_CONSOLE_H
+#include <linux/kref.h>
+#include <linux/tty.h>
+#include <linux/spinlock.h>
+
+/*
+ * This is the max number of console adapters that can/will be found as
+ * console devices on first stage console init.  Any number beyond this range
+ * can't be used as a console device but is still a valid tty device.
+ */
+#define MAX_NR_HVC_CONSOLES	16
+
+/*
+ * The Linux TTY code does not support dynamic addition of tty derived devices
+ * so we need to know how many tty devices we might need when space is allocated
+ * for the tty device.  Since this driver supports hotplug of vty adapters we
+ * need to make sure we have enough allocated.
+ */
+#define HVC_ALLOC_TTY_ADAPTERS	8
+
+struct hvc_struct {
+	struct tty_port port;
+	spinlock_t lock;
+	int index;
+	int do_wakeup;
+	char *outbuf;
+	int outbuf_size;
+	int n_outbuf;
+	uint32_t vtermno;
+	const struct hv_ops *ops;
+	int irq_requested;
+	int data;
+	struct winsize ws;
+	struct work_struct tty_resize;
+	struct list_head next;
+};
+
+/* implemented by a low level driver */
+struct hv_ops {
+	int (*get_chars)(uint32_t vtermno, char *buf, int count);
+	int (*put_chars)(uint32_t vtermno, const char *buf, int count);
+
+	/* Callbacks for notification. Called in open, close and hangup */
+	int (*notifier_add)(struct hvc_struct *hp, int irq);
+	void (*notifier_del)(struct hvc_struct *hp, int irq);
+	void (*notifier_hangup)(struct hvc_struct *hp, int irq);
+
+	/* tiocmget/set implementation */
+	int (*tiocmget)(struct hvc_struct *hp);
+	int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear);
+
+	/* Callbacks to handle tty ports */
+	void (*dtr_rts)(struct hvc_struct *hp, int raise);
+};
+
+/* Register a vterm and a slot index for use as a console (console_init) */
+extern int hvc_instantiate(uint32_t vtermno, int index,
+			   const struct hv_ops *ops);
+
+/* register a vterm for hvc tty operation (module_init or hotplug add) */
+extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
+				     const struct hv_ops *ops, int outbuf_size);
+/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
+extern int hvc_remove(struct hvc_struct *hp);
+
+/* data available */
+int hvc_poll(struct hvc_struct *hp);
+void hvc_kick(void);
+
+/* Resize hvc tty terminal window */
+extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
+
+static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&hp->lock, flags);
+	__hvc_resize(hp, ws);
+	spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+/* default notifier for irq based notification */
+extern int notifier_add_irq(struct hvc_struct *hp, int data);
+extern void notifier_del_irq(struct hvc_struct *hp, int data);
+extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
+
+
+#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
+#include <asm/xmon.h>
+#else
+static inline int cpus_are_in_xmon(void)
+{
+	return 0;
+}
+#endif
+
+#endif // HVC_CONSOLE_H

drivers/tty/hvc/hvc_dcc.c

@@ -0,0 +1,89 @@
+/* Copyright (c) 2010, 2014 The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+
+#include <asm/dcc.h>
+#include <asm/processor.h>
+
+#include "hvc_console.h"
+
+/* DCC Status Bits */
+#define DCC_STATUS_RX		(1 << 30)
+#define DCC_STATUS_TX		(1 << 29)
+
+static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		while (__dcc_getstatus() & DCC_STATUS_TX)
+			cpu_relax();
+
+		__dcc_putchar(buf[i]);
+	}
+
+	return count;
+}
+
+static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
+{
+	int i;
+
+	for (i = 0; i < count; ++i)
+		if (__dcc_getstatus() & DCC_STATUS_RX)
+			buf[i] = __dcc_getchar();
+		else
+			break;
+
+	return i;
+}
+
+static bool hvc_dcc_check(void)
+{
+	unsigned long time = jiffies + (HZ / 10);
+
+	/* Write a test character to check if it is handled */
+	__dcc_putchar('\n');
+
+	while (time_is_after_jiffies(time)) {
+		if (!(__dcc_getstatus() & DCC_STATUS_TX))
+			return true;
+	}
+
+	return false;
+}
+
+static const struct hv_ops hvc_dcc_get_put_ops = {
+	.get_chars = hvc_dcc_get_chars,
+	.put_chars = hvc_dcc_put_chars,
+};
+
+static int __init hvc_dcc_console_init(void)
+{
+	if (!hvc_dcc_check())
+		return -ENODEV;
+
+	hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
+	return 0;
+}
+console_initcall(hvc_dcc_console_init);
+
+static int __init hvc_dcc_init(void)
+{
+	if (!hvc_dcc_check())
+		return -ENODEV;
+
+	hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
+	return 0;
+}
+device_initcall(hvc_dcc_init);

drivers/tty/hvc/hvc_irq.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright IBM Corp. 2001,2008
+ *
+ * This file contains the IRQ specific code for hvc_console
+ *
+ */
+
+#include <linux/interrupt.h>
+
+#include "hvc_console.h"
+
+static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
+{
+	/* if hvc_poll request a repoll, then kick the hvcd thread */
+	if (hvc_poll(dev_instance))
+		hvc_kick();
+	return IRQ_HANDLED;
+}
+
+/*
+ * For IRQ based systems these callbacks can be used
+ */
+int notifier_add_irq(struct hvc_struct *hp, int irq)
+{
+	int rc;
+
+	if (!irq) {
+		hp->irq_requested = 0;
+		return 0;
+	}
+	rc = request_irq(irq, hvc_handle_interrupt, 0,
+			   "hvc_console", hp);
+	if (!rc)
+		hp->irq_requested = 1;
+	return rc;
+}
+
+void notifier_del_irq(struct hvc_struct *hp, int irq)
+{
+	if (!hp->irq_requested)
+		return;
+	free_irq(irq, hp);
+	hp->irq_requested = 0;
+}
+
+void notifier_hangup_irq(struct hvc_struct *hp, int irq)
+{
+	notifier_del_irq(hp, irq);
+}

drivers/tty/hvc/hvc_opal.c

@@ -0,0 +1,430 @@
+/*
+ * opal driver interface to hvc_console.c
+ *
+ * Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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
+ *
+ */
+
+#undef DEBUG
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/console.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/export.h>
+
+#include <asm/hvconsole.h>
+#include <asm/prom.h>
+#include <asm/firmware.h>
+#include <asm/hvsi.h>
+#include <asm/udbg.h>
+#include <asm/opal.h>
+
+#include "hvc_console.h"
+
+static const char hvc_opal_name[] = "hvc_opal";
+
+static struct of_device_id hvc_opal_match[] = {
+	{ .name = "serial", .compatible = "ibm,opal-console-raw" },
+	{ .name = "serial", .compatible = "ibm,opal-console-hvsi" },
+	{ },
+};
+
+typedef enum hv_protocol {
+	HV_PROTOCOL_RAW,
+	HV_PROTOCOL_HVSI
+} hv_protocol_t;
+
+struct hvc_opal_priv {
+	hv_protocol_t		proto;	/* Raw data or HVSI packets */
+	struct hvsi_priv	hvsi;	/* HVSI specific data */
+};
+static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
+
+/* For early boot console */
+static struct hvc_opal_priv hvc_opal_boot_priv;
+static u32 hvc_opal_boot_termno;
+static bool hvc_opal_event_registered;
+
+static const struct hv_ops hvc_opal_raw_ops = {
+	.get_chars = opal_get_chars,
+	.put_chars = opal_put_chars,
+	.notifier_add = notifier_add_irq,
+	.notifier_del = notifier_del_irq,
+	.notifier_hangup = notifier_hangup_irq,
+};
+
+static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
+
+	if (WARN_ON(!pv))
+		return -ENODEV;
+
+	return hvsilib_get_chars(&pv->hvsi, buf, count);
+}
+
+static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
+
+	if (WARN_ON(!pv))
+		return -ENODEV;
+
+	return hvsilib_put_chars(&pv->hvsi, buf, count);
+}
+
+static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
+	int rc;
+
+	pr_devel("HVSI@%x: do open !\n", hp->vtermno);
+
+	rc = notifier_add_irq(hp, data);
+	if (rc)
+		return rc;
+
+	return hvsilib_open(&pv->hvsi, hp);
+}
+
+static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: do close !\n", hp->vtermno);
+
+	hvsilib_close(&pv->hvsi, hp);
+
+	notifier_del_irq(hp, data);
+}
+
+void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
+
+	hvsilib_close(&pv->hvsi, hp);
+
+	notifier_hangup_irq(hp, data);
+}
+
+static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
+
+	if (!pv)
+		return -EINVAL;
+	return pv->hvsi.mctrl;
+}
+
+static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
+				unsigned int clear)
+{
+	struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
+		 hp->vtermno, set, clear);
+
+	if (set & TIOCM_DTR)
+		hvsilib_write_mctrl(&pv->hvsi, 1);
+	else if (clear & TIOCM_DTR)
+		hvsilib_write_mctrl(&pv->hvsi, 0);
+
+	return 0;
+}
+
+static const struct hv_ops hvc_opal_hvsi_ops = {
+	.get_chars = hvc_opal_hvsi_get_chars,
+	.put_chars = hvc_opal_hvsi_put_chars,
+	.notifier_add = hvc_opal_hvsi_open,
+	.notifier_del = hvc_opal_hvsi_close,
+	.notifier_hangup = hvc_opal_hvsi_hangup,
+	.tiocmget = hvc_opal_hvsi_tiocmget,
+	.tiocmset = hvc_opal_hvsi_tiocmset,
+};
+
+static int hvc_opal_console_event(struct notifier_block *nb,
+				  unsigned long events, void *change)
+{
+	if (events & OPAL_EVENT_CONSOLE_INPUT)
+		hvc_kick();
+	return 0;
+}
+
+static struct notifier_block hvc_opal_console_nb = {
+	.notifier_call	= hvc_opal_console_event,
+};
+
+static int hvc_opal_probe(struct platform_device *dev)
+{
+	const struct hv_ops *ops;
+	struct hvc_struct *hp;
+	struct hvc_opal_priv *pv;
+	hv_protocol_t proto;
+	unsigned int termno, boot = 0;
+	const __be32 *reg;
+
+
+	if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
+		proto = HV_PROTOCOL_RAW;
+		ops = &hvc_opal_raw_ops;
+	} else if (of_device_is_compatible(dev->dev.of_node,
+					   "ibm,opal-console-hvsi")) {
+		proto = HV_PROTOCOL_HVSI;
+		ops = &hvc_opal_hvsi_ops;
+	} else {
+		pr_err("hvc_opal: Unknown protocol for %s\n",
+		       dev->dev.of_node->full_name);
+		return -ENXIO;
+	}
+
+	reg = of_get_property(dev->dev.of_node, "reg", NULL);
+	termno = reg ? be32_to_cpup(reg) : 0;
+
+	/* Is it our boot one ? */
+	if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
+		pv = hvc_opal_privs[termno];
+		boot = 1;
+	} else if (hvc_opal_privs[termno] == NULL) {
+		pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
+		if (!pv)
+			return -ENOMEM;
+		pv->proto = proto;
+		hvc_opal_privs[termno] = pv;
+		if (proto == HV_PROTOCOL_HVSI)
+			hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars,
+				     termno, 0);
+
+		/* Instanciate now to establish a mapping index==vtermno */
+		hvc_instantiate(termno, termno, ops);
+	} else {
+		pr_err("hvc_opal: Device %s has duplicate terminal number #%d\n",
+		       dev->dev.of_node->full_name, termno);
+		return -ENXIO;
+	}
+
+	pr_info("hvc%d: %s protocol on %s%s\n", termno,
+		proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
+		dev->dev.of_node->full_name,
+		boot ? " (boot console)" : "");
+
+	/* We don't do IRQ ... */
+	hp = hvc_alloc(termno, 0, ops, MAX_VIO_PUT_CHARS);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+	dev_set_drvdata(&dev->dev, hp);
+
+	/* ...  but we use OPAL event to kick the console */
+	if (!hvc_opal_event_registered) {
+		opal_notifier_register(&hvc_opal_console_nb);
+		hvc_opal_event_registered = true;
+	}
+
+	return 0;
+}
+
+static int hvc_opal_remove(struct platform_device *dev)
+{
+	struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
+	int rc, termno;
+
+	termno = hp->vtermno;
+	rc = hvc_remove(hp);
+	if (rc == 0) {
+		if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
+			kfree(hvc_opal_privs[termno]);
+		hvc_opal_privs[termno] = NULL;
+	}
+	return rc;
+}
+
+static struct platform_driver hvc_opal_driver = {
+	.probe		= hvc_opal_probe,
+	.remove		= hvc_opal_remove,
+	.driver		= {
+		.name	= hvc_opal_name,
+		.owner	= THIS_MODULE,
+		.of_match_table	= hvc_opal_match,
+	}
+};
+
+static int __init hvc_opal_init(void)
+{
+	if (!firmware_has_feature(FW_FEATURE_OPAL))
+		return -ENODEV;
+
+	/* Register as a vio device to receive callbacks */
+	return platform_driver_register(&hvc_opal_driver);
+}
+device_initcall(hvc_opal_init);
+
+static void udbg_opal_putc(char c)
+{
+	unsigned int termno = hvc_opal_boot_termno;
+	int count = -1;
+
+	if (c == '\n')
+		udbg_opal_putc('\r');
+
+	do {
+		switch(hvc_opal_boot_priv.proto) {
+		case HV_PROTOCOL_RAW:
+			count = opal_put_chars(termno, &c, 1);
+			break;
+		case HV_PROTOCOL_HVSI:
+			count = hvc_opal_hvsi_put_chars(termno, &c, 1);
+			break;
+		}
+	} while(count == 0 || count == -EAGAIN);
+}
+
+static int udbg_opal_getc_poll(void)
+{
+	unsigned int termno = hvc_opal_boot_termno;
+	int rc = 0;
+	char c;
+
+	switch(hvc_opal_boot_priv.proto) {
+	case HV_PROTOCOL_RAW:
+		rc = opal_get_chars(termno, &c, 1);
+		break;
+	case HV_PROTOCOL_HVSI:
+		rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
+		break;
+	}
+	if (!rc)
+		return -1;
+	return c;
+}
+
+static int udbg_opal_getc(void)
+{
+	int ch;
+	for (;;) {
+		ch = udbg_opal_getc_poll();
+		if (ch == -1) {
+			/* This shouldn't be needed...but... */
+			volatile unsigned long delay;
+			for (delay=0; delay < 2000000; delay++)
+				;
+		} else {
+			return ch;
+		}
+	}
+}
+
+static void udbg_init_opal_common(void)
+{
+	udbg_putc = udbg_opal_putc;
+	udbg_getc = udbg_opal_getc;
+	udbg_getc_poll = udbg_opal_getc_poll;
+	tb_ticks_per_usec = 0x200; /* Make udelay not suck */
+}
+
+void __init hvc_opal_init_early(void)
+{
+	struct device_node *stdout_node = of_node_get(of_stdout);
+	const __be32 *termno;
+	const struct hv_ops *ops;
+	u32 index;
+
+	/* If the console wasn't in /chosen, try /ibm,opal */
+	if (!stdout_node) {
+		struct device_node *opal, *np;
+
+		/* Current OPAL takeover doesn't provide the stdout
+		 * path, so we hard wire it
+		 */
+		opal = of_find_node_by_path("/ibm,opal/consoles");
+		if (opal)
+			pr_devel("hvc_opal: Found consoles in new location\n");
+		if (!opal) {
+			opal = of_find_node_by_path("/ibm,opal");
+			if (opal)
+				pr_devel("hvc_opal: "
+					 "Found consoles in old location\n");
+		}
+		if (!opal)
+			return;
+		for_each_child_of_node(opal, np) {
+			if (!strcmp(np->name, "serial")) {
+				stdout_node = np;
+				break;
+			}
+		}
+		of_node_put(opal);
+	}
+	if (!stdout_node)
+		return;
+	termno = of_get_property(stdout_node, "reg", NULL);
+	index = termno ? be32_to_cpup(termno) : 0;
+	if (index >= MAX_NR_HVC_CONSOLES)
+		return;
+	hvc_opal_privs[index] = &hvc_opal_boot_priv;
+
+	/* Check the protocol */
+	if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
+		hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
+		ops = &hvc_opal_raw_ops;
+		pr_devel("hvc_opal: Found RAW console\n");
+	}
+	else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
+		hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
+		ops = &hvc_opal_hvsi_ops;
+		hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars,
+			     opal_put_chars, index, 1);
+		/* HVSI, perform the handshake now */
+		hvsilib_establish(&hvc_opal_boot_priv.hvsi);
+		pr_devel("hvc_opal: Found HVSI console\n");
+	} else
+		goto out;
+	hvc_opal_boot_termno = index;
+	udbg_init_opal_common();
+	add_preferred_console("hvc", index, NULL);
+	hvc_instantiate(index, index, ops);
+out:
+	of_node_put(stdout_node);
+}
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
+void __init udbg_init_debug_opal_raw(void)
+{
+	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
+	hvc_opal_privs[index] = &hvc_opal_boot_priv;
+	hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
+	hvc_opal_boot_termno = index;
+	udbg_init_opal_common();
+}
+#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
+void __init udbg_init_debug_opal_hvsi(void)
+{
+	u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
+	hvc_opal_privs[index] = &hvc_opal_boot_priv;
+	hvc_opal_boot_termno = index;
+	udbg_init_opal_common();
+	hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars,
+		     index, 1);
+	hvsilib_establish(&hvc_opal_boot_priv.hvsi);
+}
+#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */

drivers/tty/hvc/hvc_rtas.c

@@ -0,0 +1,123 @@
+/*
+ * IBM RTAS driver interface to hvc_console.c
+ *
+ * (C) Copyright IBM Corporation 2001-2005
+ * (C) Copyright Red Hat, Inc. 2005
+ *
+ * Author(s): Maximino Augilar <IBM STI Design Center>
+ *	    : Ryan S. Arnold <rsa@us.ibm.com>
+ *	    : Utz Bacher <utz.bacher@de.ibm.com>
+ *	    : David Woodhouse <dwmw2@infradead.org>
+ *
+ *    inspired by drivers/char/hvc_console.c
+ *    written by Anton Blanchard and Paul Mackerras
+ *
+ * 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
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include <asm/irq.h>
+#include <asm/rtas.h>
+#include "hvc_console.h"
+
+#define hvc_rtas_cookie 0x67781e15
+struct hvc_struct *hvc_rtas_dev;
+
+static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
+static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
+
+static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
+		int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
+			break;
+	}
+
+	return i;
+}
+
+static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
+{
+	int i, c;
+
+	for (i = 0; i < count; i++) {
+		if (rtas_call(rtascons_get_char_token, 0, 2, &c))
+			break;
+
+		buf[i] = c;
+	}
+
+	return i;
+}
+
+static const struct hv_ops hvc_rtas_get_put_ops = {
+	.get_chars = hvc_rtas_read_console,
+	.put_chars = hvc_rtas_write_console,
+};
+
+static int __init hvc_rtas_init(void)
+{
+	struct hvc_struct *hp;
+
+	if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+		rtascons_put_char_token = rtas_token("put-term-char");
+	if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+		return -EIO;
+
+	if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+		rtascons_get_char_token = rtas_token("get-term-char");
+	if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+		return -EIO;
+
+	BUG_ON(hvc_rtas_dev);
+
+	/* Allocate an hvc_struct for the console device we instantiated
+	 * earlier.  Save off hp so that we can return it on exit */
+	hp = hvc_alloc(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops, 16);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+
+	hvc_rtas_dev = hp;
+
+	return 0;
+}
+device_initcall(hvc_rtas_init);
+
+/* This will happen prior to module init.  There is no tty at this time? */
+static int __init hvc_rtas_console_init(void)
+{
+	rtascons_put_char_token = rtas_token("put-term-char");
+	if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+		return -EIO;
+
+	rtascons_get_char_token = rtas_token("get-term-char");
+	if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+		return -EIO;
+
+	hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
+	add_preferred_console("hvc", 0, NULL);
+
+	return 0;
+}
+console_initcall(hvc_rtas_console_init);

drivers/tty/hvc/hvc_tile.c

@@ -0,0 +1,205 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * Tilera TILE Processor hypervisor console
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+#include <asm/setup.h>
+#include <arch/sim_def.h>
+
+#include <hv/hypervisor.h>
+
+#include "hvc_console.h"
+
+static int use_sim_console;
+static int __init sim_console(char *str)
+{
+	use_sim_console = 1;
+	return 0;
+}
+early_param("sim_console", sim_console);
+
+int tile_console_write(const char *buf, int count)
+{
+	if (unlikely(use_sim_console)) {
+		int i;
+		for (i = 0; i < count; ++i)
+			__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+				     (buf[i] << _SIM_CONTROL_OPERATOR_BITS));
+		__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
+			     (SIM_PUTC_FLUSH_BINARY <<
+			      _SIM_CONTROL_OPERATOR_BITS));
+		return 0;
+	} else {
+		return hv_console_write((HV_VirtAddr)buf, count);
+	}
+}
+
+static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
+{
+	return tile_console_write(buf, count);
+}
+
+static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
+{
+	int i, c;
+
+	for (i = 0; i < count; ++i) {
+		c = hv_console_read_if_ready();
+		if (c < 0)
+			break;
+		buf[i] = c;
+	}
+
+	return i;
+}
+
+#ifdef __tilegx__
+/*
+ * IRQ based callbacks.
+ */
+static int hvc_tile_notifier_add_irq(struct hvc_struct *hp, int irq)
+{
+	int rc;
+	int cpu = raw_smp_processor_id();  /* Choose an arbitrary cpu */
+	HV_Coord coord = { .x = cpu_x(cpu), .y = cpu_y(cpu) };
+
+	rc = notifier_add_irq(hp, irq);
+	if (rc)
+		return rc;
+
+	/*
+	 * Request that the hypervisor start sending us interrupts.
+	 * If the hypervisor returns an error, we still return 0, so that
+	 * we can fall back to polling.
+	 */
+	if (hv_console_set_ipi(KERNEL_PL, irq, coord) < 0)
+		notifier_del_irq(hp, irq);
+
+	return 0;
+}
+
+static void hvc_tile_notifier_del_irq(struct hvc_struct *hp, int irq)
+{
+	HV_Coord coord = { 0, 0 };
+
+	/* Tell the hypervisor to stop sending us interrupts. */
+	hv_console_set_ipi(KERNEL_PL, -1, coord);
+
+	notifier_del_irq(hp, irq);
+}
+
+static void hvc_tile_notifier_hangup_irq(struct hvc_struct *hp, int irq)
+{
+	hvc_tile_notifier_del_irq(hp, irq);
+}
+#endif
+
+static const struct hv_ops hvc_tile_get_put_ops = {
+	.get_chars = hvc_tile_get_chars,
+	.put_chars = hvc_tile_put_chars,
+#ifdef __tilegx__
+	.notifier_add = hvc_tile_notifier_add_irq,
+	.notifier_del = hvc_tile_notifier_del_irq,
+	.notifier_hangup = hvc_tile_notifier_hangup_irq,
+#endif
+};
+
+
+#ifdef __tilegx__
+static int hvc_tile_probe(struct platform_device *pdev)
+{
+	struct hvc_struct *hp;
+	int tile_hvc_irq;
+
+	/* Create our IRQ and register it. */
+	tile_hvc_irq = irq_alloc_hwirq(-1);
+	if (!tile_hvc_irq)
+		return -ENXIO;
+
+	tile_irq_activate(tile_hvc_irq, TILE_IRQ_PERCPU);
+	hp = hvc_alloc(0, tile_hvc_irq, &hvc_tile_get_put_ops, 128);
+	if (IS_ERR(hp)) {
+		irq_free_hwirq(tile_hvc_irq);
+		return PTR_ERR(hp);
+	}
+	dev_set_drvdata(&pdev->dev, hp);
+
+	return 0;
+}
+
+static int hvc_tile_remove(struct platform_device *pdev)
+{
+	int rc;
+	struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);
+
+	rc = hvc_remove(hp);
+	if (rc == 0)
+		irq_free_hwirq(hp->data);
+
+	return rc;
+}
+
+static void hvc_tile_shutdown(struct platform_device *pdev)
+{
+	struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);
+
+	hvc_tile_notifier_del_irq(hp, hp->data);
+}
+
+static struct platform_device hvc_tile_pdev = {
+	.name           = "hvc-tile",
+	.id             = 0,
+};
+
+static struct platform_driver hvc_tile_driver = {
+	.probe          = hvc_tile_probe,
+	.remove         = hvc_tile_remove,
+	.shutdown	= hvc_tile_shutdown,
+	.driver         = {
+		.name   = "hvc-tile",
+		.owner  = THIS_MODULE,
+	}
+};
+#endif
+
+static int __init hvc_tile_console_init(void)
+{
+	hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
+	add_preferred_console("hvc", 0, NULL);
+	return 0;
+}
+console_initcall(hvc_tile_console_init);
+
+static int __init hvc_tile_init(void)
+{
+#ifndef __tilegx__
+	struct hvc_struct *hp;
+	hp = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
+	return PTR_ERR_OR_ZERO(hp);
+#else
+	platform_device_register(&hvc_tile_pdev);
+	return platform_driver_register(&hvc_tile_driver);
+#endif
+}
+device_initcall(hvc_tile_init);

drivers/tty/hvc/hvc_udbg.c

@@ -0,0 +1,95 @@
+/*
+ * udbg interface to hvc_console.c
+ *
+ * (C) Copyright David Gibson, IBM Corporation 2008.
+ *
+ * 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
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/irq.h>
+
+#include <asm/udbg.h>
+
+#include "hvc_console.h"
+
+struct hvc_struct *hvc_udbg_dev;
+
+static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
+{
+	int i;
+
+	for (i = 0; i < count && udbg_putc; i++)
+		udbg_putc(buf[i]);
+
+	return i;
+}
+
+static int hvc_udbg_get(uint32_t vtermno, char *buf, int count)
+{
+	int i, c;
+
+	if (!udbg_getc_poll)
+		return 0;
+
+	for (i = 0; i < count; i++) {
+		if ((c = udbg_getc_poll()) == -1)
+			break;
+		buf[i] = c;
+	}
+
+	return i;
+}
+
+static const struct hv_ops hvc_udbg_ops = {
+	.get_chars = hvc_udbg_get,
+	.put_chars = hvc_udbg_put,
+};
+
+static int __init hvc_udbg_init(void)
+{
+	struct hvc_struct *hp;
+
+	if (!udbg_putc)
+		return -ENODEV;
+
+	BUG_ON(hvc_udbg_dev);
+
+	hp = hvc_alloc(0, 0, &hvc_udbg_ops, 16);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+
+	hvc_udbg_dev = hp;
+
+	return 0;
+}
+device_initcall(hvc_udbg_init);
+
+static int __init hvc_udbg_console_init(void)
+{
+	if (!udbg_putc)
+		return -ENODEV;
+
+	hvc_instantiate(0, 0, &hvc_udbg_ops);
+	add_preferred_console("hvc", 0, NULL);
+
+	return 0;
+}
+console_initcall(hvc_udbg_console_init);

drivers/tty/hvc/hvc_vio.c

@@ -0,0 +1,490 @@
+/*
+ * vio driver interface to hvc_console.c
+ *
+ * This code was moved here to allow the remaining code to be reused as a
+ * generic polling mode with semi-reliable transport driver core to the
+ * console and tty subsystems.
+ *
+ *
+ * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
+ * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
+ * Copyright (C) 2004 IBM Corporation
+ *
+ * Additional Author(s):
+ *  Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ * TODO:
+ *
+ *   - handle error in sending hvsi protocol packets
+ *   - retry nego on subsequent sends ?
+ */
+
+#undef DEBUG
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/console.h>
+#include <linux/module.h>
+
+#include <asm/hvconsole.h>
+#include <asm/vio.h>
+#include <asm/prom.h>
+#include <asm/hvsi.h>
+#include <asm/udbg.h>
+#include <asm/machdep.h>
+
+#include "hvc_console.h"
+
+static const char hvc_driver_name[] = "hvc_console";
+
+static struct vio_device_id hvc_driver_table[] = {
+	{"serial", "hvterm1"},
+#ifndef HVC_OLD_HVSI
+	{"serial", "hvterm-protocol"},
+#endif
+	{ "", "" }
+};
+MODULE_DEVICE_TABLE(vio, hvc_driver_table);
+
+typedef enum hv_protocol {
+	HV_PROTOCOL_RAW,
+	HV_PROTOCOL_HVSI
+} hv_protocol_t;
+
+struct hvterm_priv {
+	u32			termno;	/* HV term number */
+	hv_protocol_t		proto;	/* Raw data or HVSI packets */
+	struct hvsi_priv	hvsi;	/* HVSI specific data */
+	spinlock_t		buf_lock;
+	char			buf[SIZE_VIO_GET_CHARS];
+	int			left;
+	int			offset;
+};
+static struct hvterm_priv *hvterm_privs[MAX_NR_HVC_CONSOLES];
+/* For early boot console */
+static struct hvterm_priv hvterm_priv0;
+
+static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count)
+{
+	struct hvterm_priv *pv = hvterm_privs[vtermno];
+	unsigned long i;
+	unsigned long flags;
+	int got;
+
+	if (WARN_ON(!pv))
+		return 0;
+
+	spin_lock_irqsave(&pv->buf_lock, flags);
+
+	if (pv->left == 0) {
+		pv->offset = 0;
+		pv->left = hvc_get_chars(pv->termno, pv->buf, count);
+
+		/*
+		 * Work around a HV bug where it gives us a null
+		 * after every \r.  -- paulus
+		 */
+		for (i = 1; i < pv->left; ++i) {
+			if (pv->buf[i] == 0 && pv->buf[i-1] == '\r') {
+				--pv->left;
+				if (i < pv->left) {
+					memmove(&pv->buf[i], &pv->buf[i+1],
+						pv->left - i);
+				}
+			}
+		}
+	}
+
+	got = min(count, pv->left);
+	memcpy(buf, &pv->buf[pv->offset], got);
+	pv->offset += got;
+	pv->left -= got;
+
+	spin_unlock_irqrestore(&pv->buf_lock, flags);
+
+	return got;
+}
+
+static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count)
+{
+	struct hvterm_priv *pv = hvterm_privs[vtermno];
+
+	if (WARN_ON(!pv))
+		return 0;
+
+	return hvc_put_chars(pv->termno, buf, count);
+}
+
+static const struct hv_ops hvterm_raw_ops = {
+	.get_chars = hvterm_raw_get_chars,
+	.put_chars = hvterm_raw_put_chars,
+	.notifier_add = notifier_add_irq,
+	.notifier_del = notifier_del_irq,
+	.notifier_hangup = notifier_hangup_irq,
+};
+
+static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
+{
+	struct hvterm_priv *pv = hvterm_privs[vtermno];
+
+	if (WARN_ON(!pv))
+		return 0;
+
+	return hvsilib_get_chars(&pv->hvsi, buf, count);
+}
+
+static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
+{
+	struct hvterm_priv *pv = hvterm_privs[vtermno];
+
+	if (WARN_ON(!pv))
+		return 0;
+
+	return hvsilib_put_chars(&pv->hvsi, buf, count);
+}
+
+static int hvterm_hvsi_open(struct hvc_struct *hp, int data)
+{
+	struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
+	int rc;
+
+	pr_devel("HVSI@%x: open !\n", pv->termno);
+
+	rc = notifier_add_irq(hp, data);
+	if (rc)
+		return rc;
+
+	return hvsilib_open(&pv->hvsi, hp);
+}
+
+static void hvterm_hvsi_close(struct hvc_struct *hp, int data)
+{
+	struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: do close !\n", pv->termno);
+
+	hvsilib_close(&pv->hvsi, hp);
+
+	notifier_del_irq(hp, data);
+}
+
+void hvterm_hvsi_hangup(struct hvc_struct *hp, int data)
+{
+	struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: do hangup !\n", pv->termno);
+
+	hvsilib_close(&pv->hvsi, hp);
+
+	notifier_hangup_irq(hp, data);
+}
+
+static int hvterm_hvsi_tiocmget(struct hvc_struct *hp)
+{
+	struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
+
+	if (!pv)
+		return -EINVAL;
+	return pv->hvsi.mctrl;
+}
+
+static int hvterm_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
+				unsigned int clear)
+{
+	struct hvterm_priv *pv = hvterm_privs[hp->vtermno];
+
+	pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
+		 pv->termno, set, clear);
+
+	if (set & TIOCM_DTR)
+		hvsilib_write_mctrl(&pv->hvsi, 1);
+	else if (clear & TIOCM_DTR)
+		hvsilib_write_mctrl(&pv->hvsi, 0);
+
+	return 0;
+}
+
+static const struct hv_ops hvterm_hvsi_ops = {
+	.get_chars = hvterm_hvsi_get_chars,
+	.put_chars = hvterm_hvsi_put_chars,
+	.notifier_add = hvterm_hvsi_open,
+	.notifier_del = hvterm_hvsi_close,
+	.notifier_hangup = hvterm_hvsi_hangup,
+	.tiocmget = hvterm_hvsi_tiocmget,
+	.tiocmset = hvterm_hvsi_tiocmset,
+};
+
+static void udbg_hvc_putc(char c)
+{
+	int count = -1;
+
+	if (!hvterm_privs[0])
+		return;
+
+	if (c == '\n')
+		udbg_hvc_putc('\r');
+
+	do {
+		switch(hvterm_privs[0]->proto) {
+		case HV_PROTOCOL_RAW:
+			count = hvterm_raw_put_chars(0, &c, 1);
+			break;
+		case HV_PROTOCOL_HVSI:
+			count = hvterm_hvsi_put_chars(0, &c, 1);
+			break;
+		}
+	} while(count == 0);
+}
+
+static int udbg_hvc_getc_poll(void)
+{
+	int rc = 0;
+	char c;
+
+	if (!hvterm_privs[0])
+		return -1;
+
+	switch(hvterm_privs[0]->proto) {
+	case HV_PROTOCOL_RAW:
+		rc = hvterm_raw_get_chars(0, &c, 1);
+		break;
+	case HV_PROTOCOL_HVSI:
+		rc = hvterm_hvsi_get_chars(0, &c, 1);
+		break;
+	}
+	if (!rc)
+		return -1;
+	return c;
+}
+
+static int udbg_hvc_getc(void)
+{
+	int ch;
+
+	if (!hvterm_privs[0])
+		return -1;
+
+	for (;;) {
+		ch = udbg_hvc_getc_poll();
+		if (ch == -1) {
+			/* This shouldn't be needed...but... */
+			volatile unsigned long delay;
+			for (delay=0; delay < 2000000; delay++)
+				;
+		} else {
+			return ch;
+		}
+	}
+}
+
+static int hvc_vio_probe(struct vio_dev *vdev,
+				   const struct vio_device_id *id)
+{
+	const struct hv_ops *ops;
+	struct hvc_struct *hp;
+	struct hvterm_priv *pv;
+	hv_protocol_t proto;
+	int i, termno = -1;
+
+	/* probed with invalid parameters. */
+	if (!vdev || !id)
+		return -EPERM;
+
+	if (of_device_is_compatible(vdev->dev.of_node, "hvterm1")) {
+		proto = HV_PROTOCOL_RAW;
+		ops = &hvterm_raw_ops;
+	} else if (of_device_is_compatible(vdev->dev.of_node, "hvterm-protocol")) {
+		proto = HV_PROTOCOL_HVSI;
+		ops = &hvterm_hvsi_ops;
+	} else {
+		pr_err("hvc_vio: Unknown protocol for %s\n", vdev->dev.of_node->full_name);
+		return -ENXIO;
+	}
+
+	pr_devel("hvc_vio_probe() device %s, using %s protocol\n",
+		 vdev->dev.of_node->full_name,
+		 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi");
+
+	/* Is it our boot one ? */
+	if (hvterm_privs[0] == &hvterm_priv0 &&
+	    vdev->unit_address == hvterm_priv0.termno) {
+		pv = hvterm_privs[0];
+		termno = 0;
+		pr_devel("->boot console, using termno 0\n");
+	}
+	/* nope, allocate a new one */
+	else {
+		for (i = 0; i < MAX_NR_HVC_CONSOLES && termno < 0; i++)
+			if (!hvterm_privs[i])
+				termno = i;
+		pr_devel("->non-boot console, using termno %d\n", termno);
+		if (termno < 0)
+			return -ENODEV;
+		pv = kzalloc(sizeof(struct hvterm_priv), GFP_KERNEL);
+		if (!pv)
+			return -ENOMEM;
+		pv->termno = vdev->unit_address;
+		pv->proto = proto;
+		spin_lock_init(&pv->buf_lock);
+		hvterm_privs[termno] = pv;
+		hvsilib_init(&pv->hvsi, hvc_get_chars, hvc_put_chars,
+			     pv->termno, 0);
+	}
+
+	hp = hvc_alloc(termno, vdev->irq, ops, MAX_VIO_PUT_CHARS);
+	if (IS_ERR(hp))
+		return PTR_ERR(hp);
+	dev_set_drvdata(&vdev->dev, hp);
+
+	/* register udbg if it's not there already for console 0 */
+	if (hp->index == 0 && !udbg_putc) {
+		udbg_putc = udbg_hvc_putc;
+		udbg_getc = udbg_hvc_getc;
+		udbg_getc_poll = udbg_hvc_getc_poll;
+	}
+
+	return 0;
+}
+
+static int hvc_vio_remove(struct vio_dev *vdev)
+{
+	struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
+	int rc, termno;
+
+	termno = hp->vtermno;
+	rc = hvc_remove(hp);
+	if (rc == 0) {
+		if (hvterm_privs[termno] != &hvterm_priv0)
+			kfree(hvterm_privs[termno]);
+		hvterm_privs[termno] = NULL;
+	}
+	return rc;
+}
+
+static struct vio_driver hvc_vio_driver = {
+	.id_table	= hvc_driver_table,
+	.probe		= hvc_vio_probe,
+	.remove		= hvc_vio_remove,
+	.name		= hvc_driver_name,
+};
+
+static int __init hvc_vio_init(void)
+{
+	int rc;
+
+	/* Register as a vio device to receive callbacks */
+	rc = vio_register_driver(&hvc_vio_driver);
+
+	return rc;
+}
+module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
+
+static void __exit hvc_vio_exit(void)
+{
+	vio_unregister_driver(&hvc_vio_driver);
+}
+module_exit(hvc_vio_exit);
+
+void __init hvc_vio_init_early(void)
+{
+	const __be32 *termno;
+	const char *name;
+	const struct hv_ops *ops;
+
+	/* find the boot console from /chosen/stdout */
+	if (!of_stdout)
+		return;
+	name = of_get_property(of_stdout, "name", NULL);
+	if (!name) {
+		printk(KERN_WARNING "stdout node missing 'name' property!\n");
+		return;
+	}
+
+	/* Check if it's a virtual terminal */
+	if (strncmp(name, "vty", 3) != 0)
+		return;
+	termno = of_get_property(of_stdout, "reg", NULL);
+	if (termno == NULL)
+		return;
+	hvterm_priv0.termno = of_read_number(termno, 1);
+	spin_lock_init(&hvterm_priv0.buf_lock);
+	hvterm_privs[0] = &hvterm_priv0;
+
+	/* Check the protocol */
+	if (of_device_is_compatible(of_stdout, "hvterm1")) {
+		hvterm_priv0.proto = HV_PROTOCOL_RAW;
+		ops = &hvterm_raw_ops;
+	}
+	else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
+		hvterm_priv0.proto = HV_PROTOCOL_HVSI;
+		ops = &hvterm_hvsi_ops;
+		hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
+			     hvterm_priv0.termno, 1);
+		/* HVSI, perform the handshake now */
+		hvsilib_establish(&hvterm_priv0.hvsi);
+	} else
+		return;
+	udbg_putc = udbg_hvc_putc;
+	udbg_getc = udbg_hvc_getc;
+	udbg_getc_poll = udbg_hvc_getc_poll;
+#ifdef HVC_OLD_HVSI
+	/* When using the old HVSI driver don't register the HVC
+	 * backend for HVSI, only do udbg
+	 */
+	if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
+		return;
+#endif
+	/* Check whether the user has requested a different console. */
+	if (!strstr(boot_command_line, "console="))
+		add_preferred_console("hvc", 0, NULL);
+	hvc_instantiate(0, 0, ops);
+}
+
+/* call this from early_init() for a working debug console on
+ * vterm capable LPAR machines
+ */
+#ifdef CONFIG_PPC_EARLY_DEBUG_LPAR
+void __init udbg_init_debug_lpar(void)
+{
+	hvterm_privs[0] = &hvterm_priv0;
+	hvterm_priv0.termno = 0;
+	hvterm_priv0.proto = HV_PROTOCOL_RAW;
+	spin_lock_init(&hvterm_priv0.buf_lock);
+	udbg_putc = udbg_hvc_putc;
+	udbg_getc = udbg_hvc_getc;
+	udbg_getc_poll = udbg_hvc_getc_poll;
+}
+#endif /* CONFIG_PPC_EARLY_DEBUG_LPAR */
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI
+void __init udbg_init_debug_lpar_hvsi(void)
+{
+	hvterm_privs[0] = &hvterm_priv0;
+	hvterm_priv0.termno = CONFIG_PPC_EARLY_DEBUG_HVSI_VTERMNO;
+	hvterm_priv0.proto = HV_PROTOCOL_HVSI;
+	spin_lock_init(&hvterm_priv0.buf_lock);
+	udbg_putc = udbg_hvc_putc;
+	udbg_getc = udbg_hvc_getc;
+	udbg_getc_poll = udbg_hvc_getc_poll;
+	hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
+		     hvterm_priv0.termno, 1);
+	hvsilib_establish(&hvterm_priv0.hvsi);
+}
+#endif /* CONFIG_PPC_EARLY_DEBUG_LPAR_HVSI */

drivers/tty/hvc/hvc_xen.c

@@ -0,0 +1,654 @@
+/*
+ * xen console driver interface to hvc_console.c
+ *
+ * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
+ *
+ * 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
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+
+#include <asm/io.h>
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <xen/hvm.h>
+#include <xen/grant_table.h>
+#include <xen/page.h>
+#include <xen/events.h>
+#include <xen/interface/io/console.h>
+#include <xen/interface/sched.h>
+#include <xen/hvc-console.h>
+#include <xen/xenbus.h>
+
+#include "hvc_console.h"
+
+#define HVC_COOKIE   0x58656e /* "Xen" in hex */
+
+struct xencons_info {
+	struct list_head list;
+	struct xenbus_device *xbdev;
+	struct xencons_interface *intf;
+	unsigned int evtchn;
+	struct hvc_struct *hvc;
+	int irq;
+	int vtermno;
+	grant_ref_t gntref;
+};
+
+static LIST_HEAD(xenconsoles);
+static DEFINE_SPINLOCK(xencons_lock);
+
+/* ------------------------------------------------------------------ */
+
+static struct xencons_info *vtermno_to_xencons(int vtermno)
+{
+	struct xencons_info *entry, *n, *ret = NULL;
+
+	if (list_empty(&xenconsoles))
+			return NULL;
+
+	list_for_each_entry_safe(entry, n, &xenconsoles, list) {
+		if (entry->vtermno == vtermno) {
+			ret  = entry;
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static inline int xenbus_devid_to_vtermno(int devid)
+{
+	return devid + HVC_COOKIE;
+}
+
+static inline void notify_daemon(struct xencons_info *cons)
+{
+	/* Use evtchn: this is called early, before irq is set up. */
+	notify_remote_via_evtchn(cons->evtchn);
+}
+
+static int __write_console(struct xencons_info *xencons,
+		const char *data, int len)
+{
+	XENCONS_RING_IDX cons, prod;
+	struct xencons_interface *intf = xencons->intf;
+	int sent = 0;
+
+	cons = intf->out_cons;
+	prod = intf->out_prod;
+	mb();			/* update queue values before going on */
+	BUG_ON((prod - cons) > sizeof(intf->out));
+
+	while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
+		intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
+
+	wmb();			/* write ring before updating pointer */
+	intf->out_prod = prod;
+
+	if (sent)
+		notify_daemon(xencons);
+	return sent;
+}
+
+static int domU_write_console(uint32_t vtermno, const char *data, int len)
+{
+	int ret = len;
+	struct xencons_info *cons = vtermno_to_xencons(vtermno);
+	if (cons == NULL)
+		return -EINVAL;
+
+	/*
+	 * Make sure the whole buffer is emitted, polling if
+	 * necessary.  We don't ever want to rely on the hvc daemon
+	 * because the most interesting console output is when the
+	 * kernel is crippled.
+	 */
+	while (len) {
+		int sent = __write_console(cons, data, len);
+		
+		data += sent;
+		len -= sent;
+
+		if (unlikely(len))
+			HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
+	}
+
+	return ret;
+}
+
+static int domU_read_console(uint32_t vtermno, char *buf, int len)
+{
+	struct xencons_interface *intf;
+	XENCONS_RING_IDX cons, prod;
+	int recv = 0;
+	struct xencons_info *xencons = vtermno_to_xencons(vtermno);
+	if (xencons == NULL)
+		return -EINVAL;
+	intf = xencons->intf;
+
+	cons = intf->in_cons;
+	prod = intf->in_prod;
+	mb();			/* get pointers before reading ring */
+	BUG_ON((prod - cons) > sizeof(intf->in));
+
+	while (cons != prod && recv < len)
+		buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
+
+	mb();			/* read ring before consuming */
+	intf->in_cons = cons;
+
+	notify_daemon(xencons);
+	return recv;
+}
+
+static struct hv_ops domU_hvc_ops = {
+	.get_chars = domU_read_console,
+	.put_chars = domU_write_console,
+	.notifier_add = notifier_add_irq,
+	.notifier_del = notifier_del_irq,
+	.notifier_hangup = notifier_hangup_irq,
+};
+
+static int dom0_read_console(uint32_t vtermno, char *buf, int len)
+{
+	return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
+}
+
+/*
+ * Either for a dom0 to write to the system console, or a domU with a
+ * debug version of Xen
+ */
+static int dom0_write_console(uint32_t vtermno, const char *str, int len)
+{
+	int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
+	if (rc < 0)
+		return rc;
+
+	return len;
+}
+
+static struct hv_ops dom0_hvc_ops = {
+	.get_chars = dom0_read_console,
+	.put_chars = dom0_write_console,
+	.notifier_add = notifier_add_irq,
+	.notifier_del = notifier_del_irq,
+	.notifier_hangup = notifier_hangup_irq,
+};
+
+static int xen_hvm_console_init(void)
+{
+	int r;
+	uint64_t v = 0;
+	unsigned long mfn;
+	struct xencons_info *info;
+
+	if (!xen_hvm_domain())
+		return -ENODEV;
+
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
+		if (!info)
+			return -ENOMEM;
+	} else if (info->intf != NULL) {
+		/* already configured */
+		return 0;
+	}
+	/*
+	 * If the toolstack (or the hypervisor) hasn't set these values, the
+	 * default value is 0. Even though mfn = 0 and evtchn = 0 are
+	 * theoretically correct values, in practice they never are and they
+	 * mean that a legacy toolstack hasn't initialized the pv console correctly.
+	 */
+	r = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN, &v);
+	if (r < 0 || v == 0)
+		goto err;
+	info->evtchn = v;
+	v = 0;
+	r = hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &v);
+	if (r < 0 || v == 0)
+		goto err;
+	mfn = v;
+	info->intf = xen_remap(mfn << PAGE_SHIFT, PAGE_SIZE);
+	if (info->intf == NULL)
+		goto err;
+	info->vtermno = HVC_COOKIE;
+
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+err:
+	kfree(info);
+	return -ENODEV;
+}
+
+static int xen_pv_console_init(void)
+{
+	struct xencons_info *info;
+
+	if (!xen_pv_domain())
+		return -ENODEV;
+
+	if (!xen_start_info->console.domU.evtchn)
+		return -ENODEV;
+
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
+		if (!info)
+			return -ENOMEM;
+	} else if (info->intf != NULL) {
+		/* already configured */
+		return 0;
+	}
+	info->evtchn = xen_start_info->console.domU.evtchn;
+	info->intf = mfn_to_virt(xen_start_info->console.domU.mfn);
+	info->vtermno = HVC_COOKIE;
+
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+}
+
+static int xen_initial_domain_console_init(void)
+{
+	struct xencons_info *info;
+
+	if (!xen_initial_domain())
+		return -ENODEV;
+
+	info = vtermno_to_xencons(HVC_COOKIE);
+	if (!info) {
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
+		if (!info)
+			return -ENOMEM;
+	}
+
+	info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
+	info->vtermno = HVC_COOKIE;
+
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+}
+
+void xen_console_resume(void)
+{
+	struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE);
+	if (info != NULL && info->irq)
+		rebind_evtchn_irq(info->evtchn, info->irq);
+}
+
+static void xencons_disconnect_backend(struct xencons_info *info)
+{
+	if (info->irq > 0)
+		unbind_from_irqhandler(info->irq, NULL);
+	info->irq = 0;
+	if (info->evtchn > 0)
+		xenbus_free_evtchn(info->xbdev, info->evtchn);
+	info->evtchn = 0;
+	if (info->gntref > 0)
+		gnttab_free_grant_references(info->gntref);
+	info->gntref = 0;
+	if (info->hvc != NULL)
+		hvc_remove(info->hvc);
+	info->hvc = NULL;
+}
+
+static void xencons_free(struct xencons_info *info)
+{
+	free_page((unsigned long)info->intf);
+	info->intf = NULL;
+	info->vtermno = 0;
+	kfree(info);
+}
+
+static int xen_console_remove(struct xencons_info *info)
+{
+	xencons_disconnect_backend(info);
+	spin_lock(&xencons_lock);
+	list_del(&info->list);
+	spin_unlock(&xencons_lock);
+	if (info->xbdev != NULL)
+		xencons_free(info);
+	else {
+		if (xen_hvm_domain())
+			iounmap(info->intf);
+		kfree(info);
+	}
+	return 0;
+}
+
+#ifdef CONFIG_HVC_XEN_FRONTEND
+static int xencons_remove(struct xenbus_device *dev)
+{
+	return xen_console_remove(dev_get_drvdata(&dev->dev));
+}
+
+static int xencons_connect_backend(struct xenbus_device *dev,
+				  struct xencons_info *info)
+{
+	int ret, evtchn, devid, ref, irq;
+	struct xenbus_transaction xbt;
+	grant_ref_t gref_head;
+	unsigned long mfn;
+
+	ret = xenbus_alloc_evtchn(dev, &evtchn);
+	if (ret)
+		return ret;
+	info->evtchn = evtchn;
+	irq = bind_evtchn_to_irq(evtchn);
+	if (irq < 0)
+		return irq;
+	info->irq = irq;
+	devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
+	info->hvc = hvc_alloc(xenbus_devid_to_vtermno(devid),
+			irq, &domU_hvc_ops, 256);
+	if (IS_ERR(info->hvc))
+		return PTR_ERR(info->hvc);
+	if (xen_pv_domain())
+		mfn = virt_to_mfn(info->intf);
+	else
+		mfn = __pa(info->intf) >> PAGE_SHIFT;
+	ret = gnttab_alloc_grant_references(1, &gref_head);
+	if (ret < 0)
+		return ret;
+	info->gntref = gref_head;
+	ref = gnttab_claim_grant_reference(&gref_head);
+	if (ref < 0)
+		return ref;
+	gnttab_grant_foreign_access_ref(ref, info->xbdev->otherend_id,
+			mfn, 0);
+
+ again:
+	ret = xenbus_transaction_start(&xbt);
+	if (ret) {
+		xenbus_dev_fatal(dev, ret, "starting transaction");
+		return ret;
+	}
+	ret = xenbus_printf(xbt, dev->nodename, "ring-ref", "%d", ref);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_printf(xbt, dev->nodename, "port", "%u",
+			    evtchn);
+	if (ret)
+		goto error_xenbus;
+	ret = xenbus_transaction_end(xbt, 0);
+	if (ret) {
+		if (ret == -EAGAIN)
+			goto again;
+		xenbus_dev_fatal(dev, ret, "completing transaction");
+		return ret;
+	}
+
+	xenbus_switch_state(dev, XenbusStateInitialised);
+	return 0;
+
+ error_xenbus:
+	xenbus_transaction_end(xbt, 1);
+	xenbus_dev_fatal(dev, ret, "writing xenstore");
+	return ret;
+}
+
+static int xencons_probe(struct xenbus_device *dev,
+				  const struct xenbus_device_id *id)
+{
+	int ret, devid;
+	struct xencons_info *info;
+
+	devid = dev->nodename[strlen(dev->nodename) - 1] - '0';
+	if (devid == 0)
+		return -ENODEV;
+
+	info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+	dev_set_drvdata(&dev->dev, info);
+	info->xbdev = dev;
+	info->vtermno = xenbus_devid_to_vtermno(devid);
+	info->intf = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+	if (!info->intf)
+		goto error_nomem;
+
+	ret = xencons_connect_backend(dev, info);
+	if (ret < 0)
+		goto error;
+	spin_lock(&xencons_lock);
+	list_add_tail(&info->list, &xenconsoles);
+	spin_unlock(&xencons_lock);
+
+	return 0;
+
+ error_nomem:
+	ret = -ENOMEM;
+	xenbus_dev_fatal(dev, ret, "allocating device memory");
+ error:
+	xencons_disconnect_backend(info);
+	xencons_free(info);
+	return ret;
+}
+
+static int xencons_resume(struct xenbus_device *dev)
+{
+	struct xencons_info *info = dev_get_drvdata(&dev->dev);
+
+	xencons_disconnect_backend(info);
+	memset(info->intf, 0, PAGE_SIZE);
+	return xencons_connect_backend(dev, info);
+}
+
+static void xencons_backend_changed(struct xenbus_device *dev,
+				   enum xenbus_state backend_state)
+{
+	switch (backend_state) {
+	case XenbusStateReconfiguring:
+	case XenbusStateReconfigured:
+	case XenbusStateInitialising:
+	case XenbusStateInitialised:
+	case XenbusStateUnknown:
+		break;
+
+	case XenbusStateInitWait:
+		break;
+
+	case XenbusStateConnected:
+		xenbus_switch_state(dev, XenbusStateConnected);
+		break;
+
+	case XenbusStateClosed:
+		if (dev->state == XenbusStateClosed)
+			break;
+		/* Missed the backend's CLOSING state -- fallthrough */
+	case XenbusStateClosing:
+		xenbus_frontend_closed(dev);
+		break;
+	}
+}
+
+static const struct xenbus_device_id xencons_ids[] = {
+	{ "console" },
+	{ "" }
+};
+
+static struct xenbus_driver xencons_driver = {
+	.name = "xenconsole",
+	.ids = xencons_ids,
+	.probe = xencons_probe,
+	.remove = xencons_remove,
+	.resume = xencons_resume,
+	.otherend_changed = xencons_backend_changed,
+};
+#endif /* CONFIG_HVC_XEN_FRONTEND */
+
+static int __init xen_hvc_init(void)
+{
+	int r;
+	struct xencons_info *info;
+	const struct hv_ops *ops;
+
+	if (!xen_domain())
+		return -ENODEV;
+
+	if (xen_initial_domain()) {
+		ops = &dom0_hvc_ops;
+		r = xen_initial_domain_console_init();
+		if (r < 0)
+			return r;
+		info = vtermno_to_xencons(HVC_COOKIE);
+	} else {
+		ops = &domU_hvc_ops;
+		if (xen_hvm_domain())
+			r = xen_hvm_console_init();
+		else
+			r = xen_pv_console_init();
+		if (r < 0)
+			return r;
+
+		info = vtermno_to_xencons(HVC_COOKIE);
+		info->irq = bind_evtchn_to_irq(info->evtchn);
+	}
+	if (info->irq < 0)
+		info->irq = 0; /* NO_IRQ */
+	else
+		irq_set_noprobe(info->irq);
+
+	info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);
+	if (IS_ERR(info->hvc)) {
+		r = PTR_ERR(info->hvc);
+		spin_lock(&xencons_lock);
+		list_del(&info->list);
+		spin_unlock(&xencons_lock);
+		if (info->irq)
+			unbind_from_irqhandler(info->irq, NULL);
+		kfree(info);
+		return r;
+	}
+
+	r = 0;
+#ifdef CONFIG_HVC_XEN_FRONTEND
+	r = xenbus_register_frontend(&xencons_driver);
+#endif
+	return r;
+}
+device_initcall(xen_hvc_init);
+
+static int xen_cons_init(void)
+{
+	const struct hv_ops *ops;
+
+	if (!xen_domain())
+		return 0;
+
+	if (xen_initial_domain())
+		ops = &dom0_hvc_ops;
+	else {
+		int r;
+		ops = &domU_hvc_ops;
+
+		if (xen_hvm_domain())
+			r = xen_hvm_console_init();
+		else
+			r = xen_pv_console_init();
+		if (r < 0)
+			return r;
+	}
+
+	hvc_instantiate(HVC_COOKIE, 0, ops);
+	return 0;
+}
+console_initcall(xen_cons_init);
+
+#ifdef CONFIG_EARLY_PRINTK
+static void xenboot_write_console(struct console *console, const char *string,
+				  unsigned len)
+{
+	unsigned int linelen, off = 0;
+	const char *pos;
+
+	if (!xen_pv_domain())
+		return;
+
+	dom0_write_console(0, string, len);
+
+	if (xen_initial_domain())
+		return;
+
+	domU_write_console(0, "(early) ", 8);
+	while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
+		linelen = pos-string+off;
+		if (off + linelen > len)
+			break;
+		domU_write_console(0, string+off, linelen);
+		domU_write_console(0, "\r\n", 2);
+		off += linelen + 1;
+	}
+	if (off < len)
+		domU_write_console(0, string+off, len-off);
+}
+
+struct console xenboot_console = {
+	.name		= "xenboot",
+	.write		= xenboot_write_console,
+	.flags		= CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
+	.index		= -1,
+};
+#endif	/* CONFIG_EARLY_PRINTK */
+
+void xen_raw_console_write(const char *str)
+{
+	ssize_t len = strlen(str);
+	int rc = 0;
+
+	if (xen_domain()) {
+		rc = dom0_write_console(0, str, len);
+#ifdef CONFIG_X86
+		if (rc == -ENOSYS && xen_hvm_domain())
+			goto outb_print;
+
+	} else if (xen_cpuid_base()) {
+		int i;
+outb_print:
+		for (i = 0; i < len; i++)
+			outb(str[i], 0xe9);
+#endif
+	}
+}
+
+void xen_raw_printk(const char *fmt, ...)
+{
+	static char buf[512];
+	va_list ap;
+
+	va_start(ap, fmt);
+	vsnprintf(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+
+	xen_raw_console_write(buf);
+}

drivers/tty/hvc/hvsi_lib.c

@@ -0,0 +1,424 @@
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/console.h>
+#include <asm/hvsi.h>
+
+#include "hvc_console.h"
+
+static int hvsi_send_packet(struct hvsi_priv *pv, struct hvsi_header *packet)
+{
+	packet->seqno = cpu_to_be16(atomic_inc_return(&pv->seqno));
+
+	/* Assumes that always succeeds, works in practice */
+	return pv->put_chars(pv->termno, (char *)packet, packet->len);
+}
+
+static void hvsi_start_handshake(struct hvsi_priv *pv)
+{
+	struct hvsi_query q;
+
+	/* Reset state */
+	pv->established = 0;
+	atomic_set(&pv->seqno, 0);
+
+	pr_devel("HVSI@%x: Handshaking started\n", pv->termno);
+
+	/* Send version query */
+	q.hdr.type = VS_QUERY_PACKET_HEADER;
+	q.hdr.len = sizeof(struct hvsi_query);
+	q.verb = cpu_to_be16(VSV_SEND_VERSION_NUMBER);
+	hvsi_send_packet(pv, &q.hdr);
+}
+
+static int hvsi_send_close(struct hvsi_priv *pv)
+{
+	struct hvsi_control ctrl;
+
+	pv->established = 0;
+
+	ctrl.hdr.type = VS_CONTROL_PACKET_HEADER;
+	ctrl.hdr.len = sizeof(struct hvsi_control);
+	ctrl.verb = cpu_to_be16(VSV_CLOSE_PROTOCOL);
+	return hvsi_send_packet(pv, &ctrl.hdr);
+}
+
+static void hvsi_cd_change(struct hvsi_priv *pv, int cd)
+{
+	if (cd)
+		pv->mctrl |= TIOCM_CD;
+	else {
+		pv->mctrl &= ~TIOCM_CD;
+
+		/* We copy the existing hvsi driver semantics
+		 * here which are to trigger a hangup when
+		 * we get a carrier loss.
+		 * Closing our connection to the server will
+		 * do just that.
+		 */
+		if (!pv->is_console && pv->opened) {
+			pr_devel("HVSI@%x Carrier lost, hanging up !\n",
+				 pv->termno);
+			hvsi_send_close(pv);
+		}
+	}
+}
+
+static void hvsi_got_control(struct hvsi_priv *pv)
+{
+	struct hvsi_control *pkt = (struct hvsi_control *)pv->inbuf;
+
+	switch (be16_to_cpu(pkt->verb)) {
+	case VSV_CLOSE_PROTOCOL:
+		/* We restart the handshaking */
+		hvsi_start_handshake(pv);
+		break;
+	case VSV_MODEM_CTL_UPDATE:
+		/* Transition of carrier detect */
+		hvsi_cd_change(pv, be32_to_cpu(pkt->word) & HVSI_TSCD);
+		break;
+	}
+}
+
+static void hvsi_got_query(struct hvsi_priv *pv)
+{
+	struct hvsi_query *pkt = (struct hvsi_query *)pv->inbuf;
+	struct hvsi_query_response r;
+
+	/* We only handle version queries */
+	if (be16_to_cpu(pkt->verb) != VSV_SEND_VERSION_NUMBER)
+		return;
+
+	pr_devel("HVSI@%x: Got version query, sending response...\n",
+		 pv->termno);
+
+	/* Send version response */
+	r.hdr.type = VS_QUERY_RESPONSE_PACKET_HEADER;
+	r.hdr.len = sizeof(struct hvsi_query_response);
+	r.verb = cpu_to_be16(VSV_SEND_VERSION_NUMBER);
+	r.u.version = HVSI_VERSION;
+	r.query_seqno = pkt->hdr.seqno;
+	hvsi_send_packet(pv, &r.hdr);
+
+	/* Assume protocol is open now */
+	pv->established = 1;
+}
+
+static void hvsi_got_response(struct hvsi_priv *pv)
+{
+	struct hvsi_query_response *r =
+		(struct hvsi_query_response *)pv->inbuf;
+
+	switch(r->verb) {
+	case VSV_SEND_MODEM_CTL_STATUS:
+		hvsi_cd_change(pv, be32_to_cpu(r->u.mctrl_word) & HVSI_TSCD);
+		pv->mctrl_update = 1;
+		break;
+	}
+}
+
+static int hvsi_check_packet(struct hvsi_priv *pv)
+{
+	u8 len, type;
+
+	/* Check header validity. If it's invalid, we ditch
+	 * the whole buffer and hope we eventually resync
+	 */
+	if (pv->inbuf[0] < 0xfc) {
+		pv->inbuf_len = pv->inbuf_pktlen = 0;
+		return 0;
+	}
+	type = pv->inbuf[0];
+	len = pv->inbuf[1];
+
+	/* Packet incomplete ? */
+	if (pv->inbuf_len < len)
+		return 0;
+
+	pr_devel("HVSI@%x: Got packet type %x len %d bytes:\n",
+		 pv->termno, type, len);
+
+	/* We have a packet, yay ! Handle it */
+	switch(type) {
+	case VS_DATA_PACKET_HEADER:
+		pv->inbuf_pktlen = len - 4;
+		pv->inbuf_cur = 4;
+		return 1;
+	case VS_CONTROL_PACKET_HEADER:
+		hvsi_got_control(pv);
+		break;
+	case VS_QUERY_PACKET_HEADER:
+		hvsi_got_query(pv);
+		break;
+	case VS_QUERY_RESPONSE_PACKET_HEADER:
+		hvsi_got_response(pv);
+		break;
+	}
+
+	/* Swallow packet and retry */
+	pv->inbuf_len -= len;
+	memmove(pv->inbuf, &pv->inbuf[len], pv->inbuf_len);
+	return 1;
+}
+
+static int hvsi_get_packet(struct hvsi_priv *pv)
+{
+	/* If we have room in the buffer, ask HV for more */
+	if (pv->inbuf_len < HVSI_INBUF_SIZE)
+		pv->inbuf_len += pv->get_chars(pv->termno,
+					     &pv->inbuf[pv->inbuf_len],
+					     HVSI_INBUF_SIZE - pv->inbuf_len);
+	/*
+	 * If we have at least 4 bytes in the buffer, check for
+	 * a full packet and retry
+	 */
+	if (pv->inbuf_len >= 4)
+		return hvsi_check_packet(pv);
+	return 0;
+}
+
+int hvsilib_get_chars(struct hvsi_priv *pv, char *buf, int count)
+{
+	unsigned int tries, read = 0;
+
+	if (WARN_ON(!pv))
+		return -ENXIO;
+
+	/* If we aren't open, don't do anything in order to avoid races
+	 * with connection establishment. The hvc core will call this
+	 * before we have returned from notifier_add(), and we need to
+	 * avoid multiple users playing with the receive buffer
+	 */
+	if (!pv->opened)
+		return 0;
+
+	/* We try twice, once with what data we have and once more
+	 * after we try to fetch some more from the hypervisor
+	 */
+	for (tries = 1; count && tries < 2; tries++) {
+		/* Consume existing data packet */
+		if (pv->inbuf_pktlen) {
+			unsigned int l = min(count, (int)pv->inbuf_pktlen);
+			memcpy(&buf[read], &pv->inbuf[pv->inbuf_cur], l);
+			pv->inbuf_cur += l;
+			pv->inbuf_pktlen -= l;
+			count -= l;
+			read += l;
+		}
+		if (count == 0)
+			break;
+
+		/* Data packet fully consumed, move down remaning data */
+		if (pv->inbuf_cur) {
+			pv->inbuf_len -= pv->inbuf_cur;
+			memmove(pv->inbuf, &pv->inbuf[pv->inbuf_cur],
+				pv->inbuf_len);
+			pv->inbuf_cur = 0;
+		}
+
+		/* Try to get another packet */
+		if (hvsi_get_packet(pv))
+			tries--;
+	}
+	if (!pv->established) {
+		pr_devel("HVSI@%x: returning -EPIPE\n", pv->termno);
+		return -EPIPE;
+	}
+	return read;
+}
+
+int hvsilib_put_chars(struct hvsi_priv *pv, const char *buf, int count)
+{
+	struct hvsi_data dp;
+	int rc, adjcount = min(count, HVSI_MAX_OUTGOING_DATA);
+
+	if (WARN_ON(!pv))
+		return -ENODEV;
+
+	dp.hdr.type = VS_DATA_PACKET_HEADER;
+	dp.hdr.len = adjcount + sizeof(struct hvsi_header);
+	memcpy(dp.data, buf, adjcount);
+	rc = hvsi_send_packet(pv, &dp.hdr);
+	if (rc <= 0)
+		return rc;
+	return adjcount;
+}
+
+static void maybe_msleep(unsigned long ms)
+{
+	/* During early boot, IRQs are disabled, use mdelay */
+	if (irqs_disabled())
+		mdelay(ms);
+	else
+		msleep(ms);
+}
+
+int hvsilib_read_mctrl(struct hvsi_priv *pv)
+{
+	struct hvsi_query q;
+	int rc, timeout;
+
+	pr_devel("HVSI@%x: Querying modem control status...\n",
+		 pv->termno);
+
+	pv->mctrl_update = 0;
+	q.hdr.type = VS_QUERY_PACKET_HEADER;
+	q.hdr.len = sizeof(struct hvsi_query);
+	q.verb = cpu_to_be16(VSV_SEND_MODEM_CTL_STATUS);
+	rc = hvsi_send_packet(pv, &q.hdr);
+	if (rc <= 0) {
+		pr_devel("HVSI@%x: Error %d...\n", pv->termno, rc);
+		return rc;
+	}
+
+	/* Try for up to 200ms */
+	for (timeout = 0; timeout < 20; timeout++) {
+		if (!pv->established)
+			return -ENXIO;
+		if (pv->mctrl_update)
+			return 0;
+		if (!hvsi_get_packet(pv))
+			maybe_msleep(10);
+	}
+	return -EIO;
+}
+
+int hvsilib_write_mctrl(struct hvsi_priv *pv, int dtr)
+{
+	struct hvsi_control ctrl;
+	unsigned short mctrl;
+
+	mctrl = pv->mctrl;
+	if (dtr)
+		mctrl |= TIOCM_DTR;
+	else
+		mctrl &= ~TIOCM_DTR;
+	if (mctrl == pv->mctrl)
+		return 0;
+	pv->mctrl = mctrl;
+
+	pr_devel("HVSI@%x: %s DTR...\n", pv->termno,
+		 dtr ? "Setting" : "Clearing");
+
+	ctrl.hdr.type = VS_CONTROL_PACKET_HEADER,
+	ctrl.hdr.len = sizeof(struct hvsi_control);
+	ctrl.verb = cpu_to_be16(VSV_SET_MODEM_CTL);
+	ctrl.mask = cpu_to_be32(HVSI_TSDTR);
+	ctrl.word = cpu_to_be32(dtr ? HVSI_TSDTR : 0);
+	return hvsi_send_packet(pv, &ctrl.hdr);
+}
+
+void hvsilib_establish(struct hvsi_priv *pv)
+{
+	int timeout;
+
+	pr_devel("HVSI@%x: Establishing...\n", pv->termno);
+
+	/* Try for up to 200ms, there can be a packet to
+	 * start the process waiting for us...
+	 */
+	for (timeout = 0; timeout < 20; timeout++) {
+		if (pv->established)
+			goto established;
+		if (!hvsi_get_packet(pv))
+			maybe_msleep(10);
+	}
+
+	/* Failed, send a close connection packet just
+	 * in case
+	 */
+	pr_devel("HVSI@%x:   ... sending close\n", pv->termno);
+
+	hvsi_send_close(pv);
+
+	/* Then restart handshake */
+
+	pr_devel("HVSI@%x:   ... restarting handshake\n", pv->termno);
+
+	hvsi_start_handshake(pv);
+
+	pr_devel("HVSI@%x:   ... waiting handshake\n", pv->termno);
+
+	/* Try for up to 400ms */
+	for (timeout = 0; timeout < 40; timeout++) {
+		if (pv->established)
+			goto established;
+		if (!hvsi_get_packet(pv))
+			maybe_msleep(10);
+	}
+
+	if (!pv->established) {
+		pr_devel("HVSI@%x: Timeout handshaking, giving up !\n",
+			 pv->termno);
+		return;
+	}
+ established:
+	/* Query modem control lines */
+
+	pr_devel("HVSI@%x:   ... established, reading mctrl\n", pv->termno);
+
+	hvsilib_read_mctrl(pv);
+
+	/* Set our own DTR */
+
+	pr_devel("HVSI@%x:   ... setting mctrl\n", pv->termno);
+
+	hvsilib_write_mctrl(pv, 1);
+
+	/* Set the opened flag so reads are allowed */
+	wmb();
+	pv->opened = 1;
+}
+
+int hvsilib_open(struct hvsi_priv *pv, struct hvc_struct *hp)
+{
+	pr_devel("HVSI@%x: open !\n", pv->termno);
+
+	/* Keep track of the tty data structure */
+	pv->tty = tty_port_tty_get(&hp->port);
+
+	hvsilib_establish(pv);
+
+	return 0;
+}
+
+void hvsilib_close(struct hvsi_priv *pv, struct hvc_struct *hp)
+{
+	unsigned long flags;
+
+	pr_devel("HVSI@%x: close !\n", pv->termno);
+
+	if (!pv->is_console) {
+		pr_devel("HVSI@%x: Not a console, tearing down\n",
+			 pv->termno);
+
+		/* Clear opened, synchronize with khvcd */
+		spin_lock_irqsave(&hp->lock, flags);
+		pv->opened = 0;
+		spin_unlock_irqrestore(&hp->lock, flags);
+
+		/* Clear our own DTR */
+		if (!pv->tty || (pv->tty->termios.c_cflag & HUPCL))
+			hvsilib_write_mctrl(pv, 0);
+
+		/* Tear down the connection */
+		hvsi_send_close(pv);
+	}
+
+	if (pv->tty)
+		tty_kref_put(pv->tty);
+	pv->tty = NULL;
+}
+
+void hvsilib_init(struct hvsi_priv *pv,
+		  int (*get_chars)(uint32_t termno, char *buf, int count),
+		  int (*put_chars)(uint32_t termno, const char *buf,
+				   int count),
+		  int termno, int is_console)
+{
+	memset(pv, 0, sizeof(*pv));
+	pv->get_chars = get_chars;
+	pv->put_chars = put_chars;
+	pv->termno = termno;
+	pv->is_console = is_console;
+}