Initial Contribution

msm-2.6.38: tag AU_LINUX_ANDROID_GINGERBREAD.02.03.04.00.142

Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
diff --git a/arch/arm/mach-msm/subsystem_restart.c b/arch/arm/mach-msm/subsystem_restart.c
new file mode 100644
index 0000000..002c9f8
--- /dev/null
+++ b/arch/arm/mach-msm/subsystem_restart.c
@@ -0,0 +1,523 @@
+/* Copyright (c) 2011, Code Aurora Forum. 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/kernel.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/delay.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/kthread.h>
+
+#include <asm/current.h>
+
+#include <mach/peripheral-loader.h>
+#include <mach/scm.h>
+#include <mach/socinfo.h>
+#include <mach/subsystem_notif.h>
+#include <mach/subsystem_restart.h>
+
+#include "smd_private.h"
+
+#if defined(SUBSYS_RESTART_DEBUG)
+#define dprintk(msg...) printk(msg)
+#else
+#define dprintk(msg...)
+#endif
+
+struct subsys_soc_restart_order {
+	const char * const *subsystem_list;
+	int count;
+
+	struct mutex shutdown_lock;
+	struct mutex powerup_lock;
+	struct subsys_data *subsys_ptrs[];
+};
+
+struct restart_thread_data {
+	struct subsys_data *subsys;
+	int coupled;
+};
+
+static int restart_level;
+static int enable_ramdumps;
+
+static LIST_HEAD(subsystem_list);
+static DEFINE_MUTEX(subsystem_list_lock);
+static DEFINE_MUTEX(soc_order_reg_lock);
+
+/* SOC specific restart orders go here */
+
+#define DEFINE_SINGLE_RESTART_ORDER(name, order)		\
+	static struct subsys_soc_restart_order __##name = {	\
+		.subsystem_list = order,			\
+		.count = ARRAY_SIZE(order),			\
+		.subsys_ptrs = {[ARRAY_SIZE(order)] = NULL}	\
+	};							\
+	static struct subsys_soc_restart_order *name[] = {      \
+		&__##name,					\
+	}
+
+/* MSM 8x60 restart ordering info */
+static const char * const _order_8x60_all[] = {
+	"external_modem",  "modem", "lpass"
+};
+DEFINE_SINGLE_RESTART_ORDER(orders_8x60_all, _order_8x60_all);
+
+static const char * const _order_8x60_modems[] = {"external_modem", "modem"};
+DEFINE_SINGLE_RESTART_ORDER(orders_8x60_modems, _order_8x60_modems);
+
+/* MSM 8960 restart ordering info */
+static const char * const order_8960[] = {"modem", "lpass"};
+
+static struct subsys_soc_restart_order restart_orders_8960_one = {
+	.subsystem_list = order_8960,
+	.count = ARRAY_SIZE(order_8960),
+	.subsys_ptrs = {[ARRAY_SIZE(order_8960)] = NULL}
+	};
+
+static struct subsys_soc_restart_order *restart_orders_8960[] = {
+	&restart_orders_8960_one,
+};
+
+/* These will be assigned to one of the sets above after
+ * runtime SoC identification.
+ */
+static struct subsys_soc_restart_order **restart_orders;
+static int n_restart_orders;
+
+module_param(enable_ramdumps, int, S_IRUGO | S_IWUSR);
+
+static struct subsys_soc_restart_order *_update_restart_order(
+		struct subsys_data *subsys);
+
+int get_restart_level()
+{
+	return restart_level;
+}
+EXPORT_SYMBOL(get_restart_level);
+
+static void restart_level_changed(void)
+{
+	struct subsys_data *subsys;
+
+	if (cpu_is_msm8x60() && restart_level == RESET_SUBSYS_COUPLED) {
+		restart_orders = orders_8x60_all;
+		n_restart_orders = ARRAY_SIZE(orders_8x60_all);
+	}
+
+	if (cpu_is_msm8x60() && restart_level == RESET_SUBSYS_MIXED) {
+		restart_orders = orders_8x60_modems;
+		n_restart_orders = ARRAY_SIZE(orders_8x60_modems);
+	}
+
+	mutex_lock(&subsystem_list_lock);
+	list_for_each_entry(subsys, &subsystem_list, list)
+		subsys->restart_order = _update_restart_order(subsys);
+	mutex_unlock(&subsystem_list_lock);
+}
+
+static int restart_level_set(const char *val, struct kernel_param *kp)
+{
+	int ret;
+	int old_val = restart_level;
+
+	ret = param_set_int(val, kp);
+	if (ret)
+		return ret;
+
+	switch (restart_level) {
+
+	case RESET_SOC:
+	case RESET_SUBSYS_COUPLED:
+	case RESET_SUBSYS_INDEPENDENT:
+		pr_info("Subsystem Restart: Phase %d behavior activated.\n",
+				restart_level);
+	break;
+
+	case RESET_SUBSYS_MIXED:
+		pr_info("Subsystem Restart: Phase 2+ behavior activated.\n");
+	break;
+
+	default:
+		restart_level = old_val;
+		return -EINVAL;
+	break;
+
+	}
+
+	if (restart_level != old_val)
+		restart_level_changed();
+
+	return 0;
+}
+
+module_param_call(restart_level, restart_level_set, param_get_int,
+			&restart_level, 0644);
+
+static struct subsys_data *_find_subsystem(const char *subsys_name)
+{
+	struct subsys_data *subsys;
+
+	mutex_lock(&subsystem_list_lock);
+	list_for_each_entry(subsys, &subsystem_list, list)
+		if (!strncmp(subsys->name, subsys_name,
+				SUBSYS_NAME_MAX_LENGTH)) {
+			mutex_unlock(&subsystem_list_lock);
+			return subsys;
+		}
+	mutex_unlock(&subsystem_list_lock);
+
+	return NULL;
+}
+
+static struct subsys_soc_restart_order *_update_restart_order(
+		struct subsys_data *subsys)
+{
+	int i, j;
+
+	if (!subsys)
+		return NULL;
+
+	if (!subsys->name)
+		return NULL;
+
+	mutex_lock(&soc_order_reg_lock);
+	for (j = 0; j < n_restart_orders; j++) {
+		for (i = 0; i < restart_orders[j]->count; i++)
+			if (!strncmp(restart_orders[j]->subsystem_list[i],
+				subsys->name, SUBSYS_NAME_MAX_LENGTH)) {
+
+					restart_orders[j]->subsys_ptrs[i] =
+						subsys;
+					mutex_unlock(&soc_order_reg_lock);
+					return restart_orders[j];
+			}
+	}
+
+	mutex_unlock(&soc_order_reg_lock);
+
+	return NULL;
+}
+
+static void _send_notification_to_order(struct subsys_data
+			**restart_list, int count,
+			enum subsys_notif_type notif_type)
+{
+	int i;
+
+	for (i = 0; i < count; i++)
+		if (restart_list[i])
+			subsys_notif_queue_notification(
+				restart_list[i]->notif_handle, notif_type);
+}
+
+static int subsystem_restart_thread(void *data)
+{
+	struct restart_thread_data *r_work = data;
+	struct subsys_data **restart_list;
+	struct subsys_data *subsys = r_work->subsys;
+	struct subsys_soc_restart_order *soc_restart_order = NULL;
+
+	struct mutex *powerup_lock;
+	struct mutex *shutdown_lock;
+
+	int i;
+	int restart_list_count = 0;
+
+	if (r_work->coupled)
+		soc_restart_order = subsys->restart_order;
+
+	/* It's OK to not take the registration lock at this point.
+	 * This is because the subsystem list inside the relevant
+	 * restart order is not being traversed.
+	 */
+	if (!soc_restart_order) {
+		restart_list = subsys->single_restart_list;
+		restart_list_count = 1;
+		powerup_lock = &subsys->powerup_lock;
+		shutdown_lock = &subsys->shutdown_lock;
+	} else {
+		restart_list = soc_restart_order->subsys_ptrs;
+		restart_list_count = soc_restart_order->count;
+		powerup_lock = &soc_restart_order->powerup_lock;
+		shutdown_lock = &soc_restart_order->shutdown_lock;
+	}
+
+	dprintk("%s[%p]: Attempting to get shutdown lock!\n", __func__,
+		current);
+
+	/* Try to acquire shutdown_lock. If this fails, these subsystems are
+	 * already being restarted - return.
+	 */
+	if (!mutex_trylock(shutdown_lock)) {
+		kfree(data);
+		do_exit(0);
+	}
+
+	dprintk("%s[%p]: Attempting to get powerup lock!\n", __func__,
+			current);
+
+	/* Now that we've acquired the shutdown lock, either we're the first to
+	 * restart these subsystems or some other thread is doing the powerup
+	 * sequence for these subsystems. In the latter case, panic and bail
+	 * out, since a subsystem died in its powerup sequence.
+	 */
+	if (!mutex_trylock(powerup_lock))
+		panic("%s: Subsystem died during powerup!", __func__);
+
+	/* Now it is necessary to take the registration lock. This is because
+	 * the subsystem list in the SoC restart order will be traversed
+	 * and it shouldn't be changed until _this_ restart sequence completes.
+	 */
+	mutex_lock(&soc_order_reg_lock);
+
+	dprintk("%s: Starting restart sequence for %s\n", __func__,
+		r_work->subsys->name);
+
+	_send_notification_to_order(restart_list,
+				restart_list_count,
+				SUBSYS_BEFORE_SHUTDOWN);
+
+	for (i = 0; i < restart_list_count; i++) {
+
+		if (!restart_list[i])
+			continue;
+
+		pr_info("subsys-restart: Shutting down %s\n",
+			restart_list[i]->name);
+
+		if (restart_list[i]->shutdown(subsys) < 0)
+			panic("%s: Failed to shutdown %s!\n", __func__,
+				restart_list[i]->name);
+	}
+
+	_send_notification_to_order(restart_list, restart_list_count,
+				SUBSYS_AFTER_SHUTDOWN);
+
+	/* Now that we've finished shutting down these subsystems, release the
+	 * shutdown lock. If a subsystem restart request comes in for a
+	 * subsystem in _this_ restart order after the unlock below, and
+	 * before the powerup lock is released, panic and bail out.
+	 */
+	mutex_unlock(shutdown_lock);
+
+	/* Collect ram dumps for all subsystems in order here */
+	for (i = 0; i < restart_list_count; i++) {
+		if (!restart_list[i])
+			continue;
+
+		if (restart_list[i]->ramdump)
+			if (restart_list[i]->ramdump(enable_ramdumps,
+							subsys) < 0)
+				pr_warn("%s(%s): Ramdump failed.", __func__,
+					restart_list[i]->name);
+	}
+
+	_send_notification_to_order(restart_list,
+			restart_list_count,
+			SUBSYS_BEFORE_POWERUP);
+
+	for (i = restart_list_count - 1; i >= 0; i--) {
+
+		if (!restart_list[i])
+			continue;
+
+		pr_info("subsys-restart: Powering up %s\n",
+			restart_list[i]->name);
+
+		if (restart_list[i]->powerup(subsys) < 0)
+			panic("%s: Failed to powerup %s!", __func__,
+				restart_list[i]->name);
+	}
+
+	_send_notification_to_order(restart_list,
+				restart_list_count,
+				SUBSYS_AFTER_POWERUP);
+
+	pr_info("%s: Restart sequence for %s completed.", __func__,
+			r_work->subsys->name);
+
+	mutex_unlock(powerup_lock);
+
+	mutex_unlock(&soc_order_reg_lock);
+
+	dprintk("%s: Released powerup lock!\n", __func__);
+
+	kfree(data);
+	do_exit(0);
+}
+
+int subsystem_restart(const char *subsys_name)
+{
+	struct subsys_data *subsys;
+	struct task_struct *tsk;
+	struct restart_thread_data *data = NULL;
+
+	if (!subsys_name) {
+		pr_err("%s: Invalid subsystem name.", __func__);
+		return -EINVAL;
+	}
+
+	pr_info("Subsystem Restart: Restart sequence requested for  %s\n",
+		subsys_name);
+
+	/* List of subsystems is protected by a lock. New subsystems can
+	 * still come in.
+	 */
+	subsys = _find_subsystem(subsys_name);
+
+	if (!subsys) {
+		pr_warn("%s: Unregistered subsystem %s!", __func__,
+				subsys_name);
+		return -EINVAL;
+	}
+
+	if (restart_level != RESET_SOC) {
+		data = kzalloc(sizeof(struct restart_thread_data), GFP_KERNEL);
+		if (!data) {
+			restart_level = RESET_SOC;
+			pr_warn("%s: Failed to alloc restart data. Resetting.",
+				__func__);
+		} else {
+			if (restart_level == RESET_SUBSYS_COUPLED ||
+					restart_level == RESET_SUBSYS_MIXED)
+				data->coupled = 1;
+			else
+				data->coupled = 0;
+
+			data->subsys = subsys;
+		}
+	}
+
+	switch (restart_level) {
+
+	case RESET_SUBSYS_COUPLED:
+	case RESET_SUBSYS_MIXED:
+	case RESET_SUBSYS_INDEPENDENT:
+		dprintk("%s: Restarting %s [level=%d]!\n", __func__,
+			subsys_name, restart_level);
+
+		/* Let the kthread handle the actual restarting. Using a
+		 * workqueue will not work since all restart requests are
+		 * serialized and it prevents the short circuiting of
+		 * restart requests for subsystems already in a restart
+		 * sequence.
+		 */
+		tsk = kthread_run(subsystem_restart_thread, data,
+				"subsystem_subsystem_restart_thread");
+		if (IS_ERR(tsk))
+			panic("%s: Unable to create thread to restart %s",
+				__func__, subsys->name);
+
+		break;
+
+	case RESET_SOC:
+
+		mutex_lock(&subsystem_list_lock);
+		list_for_each_entry(subsys, &subsystem_list, list)
+			if (subsys->crash_shutdown)
+				subsys->crash_shutdown(subsys);
+		mutex_unlock(&subsystem_list_lock);
+
+		panic("Resetting the SOC");
+		break;
+
+	default:
+		panic("subsys-restart: Unknown restart level!\n");
+	break;
+
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(subsystem_restart);
+
+int ssr_register_subsystem(struct subsys_data *subsys)
+{
+	if (!subsys)
+		goto err;
+
+	if (!subsys->name)
+		goto err;
+
+	if (!subsys->powerup || !subsys->shutdown)
+		goto err;
+
+	subsys->notif_handle = subsys_notif_add_subsys(subsys->name);
+	subsys->restart_order = _update_restart_order(subsys);
+	subsys->single_restart_list[0] = subsys;
+
+	mutex_init(&subsys->shutdown_lock);
+	mutex_init(&subsys->powerup_lock);
+
+	mutex_lock(&subsystem_list_lock);
+	list_add(&subsys->list, &subsystem_list);
+	mutex_unlock(&subsystem_list_lock);
+
+	return 0;
+
+err:
+	return -EINVAL;
+}
+EXPORT_SYMBOL(ssr_register_subsystem);
+
+static int __init ssr_init_soc_restart_orders(void)
+{
+	int i;
+
+	if (cpu_is_msm8x60()) {
+		for (i = 0; i < ARRAY_SIZE(orders_8x60_all); i++) {
+			mutex_init(&orders_8x60_all[i]->powerup_lock);
+			mutex_init(&orders_8x60_all[i]->shutdown_lock);
+		}
+
+		for (i = 0; i < ARRAY_SIZE(orders_8x60_modems); i++) {
+			mutex_init(&orders_8x60_modems[i]->powerup_lock);
+			mutex_init(&orders_8x60_modems[i]->shutdown_lock);
+		}
+
+		restart_orders = orders_8x60_all;
+		n_restart_orders = ARRAY_SIZE(orders_8x60_all);
+	}
+
+	if (cpu_is_msm8960()) {
+		restart_orders = restart_orders_8960;
+		n_restart_orders = ARRAY_SIZE(restart_orders_8960);
+	}
+
+	if (restart_orders == NULL || n_restart_orders < 1) {
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __init subsys_restart_init(void)
+{
+	int ret = 0;
+
+	restart_level = RESET_SOC;
+
+	ret = ssr_init_soc_restart_orders();
+
+	return ret;
+}
+
+arch_initcall(subsys_restart_init);
+
+MODULE_DESCRIPTION("Subsystem Restart Driver");
+MODULE_LICENSE("GPL v2");