blob: 9b8bc6179bf122a3c6c78c9c853630bb304a2c82 [file] [log] [blame]
/* Copyright (c) 2010-2012, 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/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include <linux/pm.h>
#include <linux/mfd/pmic8058.h>
#include <linux/jiffies.h>
#include <linux/suspend.h>
#include <linux/percpu.h>
#include <linux/interrupt.h>
#include <asm/fiq.h>
#include <asm/hardware/gic.h>
#include <mach/msm_iomap.h>
#include <asm/mach-types.h>
#include <mach/scm.h>
#include <mach/socinfo.h>
#include "msm_watchdog.h"
#include "timer.h"
#define MODULE_NAME "msm_watchdog"
#define TCSR_WDT_CFG 0x30
#define WDT0_RST 0x38
#define WDT0_EN 0x40
#define WDT0_STS 0x44
#define WDT0_BARK_TIME 0x4C
#define WDT0_BITE_TIME 0x5C
#define WDT_HZ 32768
struct msm_watchdog_dump msm_dump_cpu_ctx;
static void __iomem *msm_tmr0_base;
static unsigned long delay_time;
static unsigned long bark_time;
static unsigned long long last_pet;
static bool has_vic;
/*
* On the kernel command line specify
* msm_watchdog.enable=1 to enable the watchdog
* By default watchdog is turned on
*/
static int enable = 1;
module_param(enable, int, 0);
/*
* If the watchdog is enabled at bootup (enable=1),
* the runtime_disable sysfs node at
* /sys/module/msm_watchdog/runtime_disable
* can be used to deactivate the watchdog.
* This is a one-time setting. The watchdog
* cannot be re-enabled once it is disabled.
*/
static int runtime_disable;
static DEFINE_MUTEX(disable_lock);
static int wdog_enable_set(const char *val, struct kernel_param *kp);
module_param_call(runtime_disable, wdog_enable_set, param_get_int,
&runtime_disable, 0644);
/*
* On the kernel command line specify msm_watchdog.appsbark=1 to handle
* watchdog barks in Linux. By default barks are processed by the secure side.
*/
static int appsbark;
module_param(appsbark, int, 0);
static int appsbark_fiq;
/*
* Use /sys/module/msm_watchdog/parameters/print_all_stacks
* to control whether stacks of all running
* processes are printed when a wdog bark is received.
*/
static int print_all_stacks = 1;
module_param(print_all_stacks, int, S_IRUGO | S_IWUSR);
/* Area for context dump in secure mode */
static void *scm_regsave;
static struct msm_watchdog_pdata __percpu **percpu_pdata;
static void pet_watchdog_work(struct work_struct *work);
static void init_watchdog_work(struct work_struct *work);
static DECLARE_DELAYED_WORK(dogwork_struct, pet_watchdog_work);
static DECLARE_WORK(init_dogwork_struct, init_watchdog_work);
/* Called from the FIQ bark handler */
void msm_wdog_bark_fin(void)
{
pr_crit("\nApps Watchdog bark received - Calling Panic\n");
panic("Apps Watchdog Bark received\n");
}
static int msm_watchdog_suspend(struct device *dev)
{
if (!enable)
return 0;
__raw_writel(1, msm_tmr0_base + WDT0_RST);
__raw_writel(0, msm_tmr0_base + WDT0_EN);
mb();
return 0;
}
static int msm_watchdog_resume(struct device *dev)
{
if (!enable)
return 0;
__raw_writel(1, msm_tmr0_base + WDT0_EN);
__raw_writel(1, msm_tmr0_base + WDT0_RST);
mb();
return 0;
}
static int panic_wdog_handler(struct notifier_block *this,
unsigned long event, void *ptr)
{
if (panic_timeout == 0) {
__raw_writel(0, msm_tmr0_base + WDT0_EN);
mb();
} else {
__raw_writel(WDT_HZ * (panic_timeout + 4),
msm_tmr0_base + WDT0_BARK_TIME);
__raw_writel(WDT_HZ * (panic_timeout + 4),
msm_tmr0_base + WDT0_BITE_TIME);
__raw_writel(1, msm_tmr0_base + WDT0_RST);
}
return NOTIFY_DONE;
}
static struct notifier_block panic_blk = {
.notifier_call = panic_wdog_handler,
};
static int wdog_enable_set(const char *val, struct kernel_param *kp)
{
int ret = 0;
int old_val = runtime_disable;
mutex_lock(&disable_lock);
if (!enable) {
printk(KERN_INFO "MSM Watchdog is not active.\n");
ret = -EINVAL;
goto done;
}
ret = param_set_int(val, kp);
if (ret)
goto done;
switch (runtime_disable) {
case 1:
if (!old_val) {
__raw_writel(0, msm_tmr0_base + WDT0_EN);
mb();
if (has_vic) {
free_irq(WDT0_ACCSCSSNBARK_INT, 0);
} else {
disable_percpu_irq(WDT0_ACCSCSSNBARK_INT);
if (!appsbark_fiq) {
free_percpu_irq(WDT0_ACCSCSSNBARK_INT,
percpu_pdata);
free_percpu(percpu_pdata);
}
}
enable = 0;
atomic_notifier_chain_unregister(&panic_notifier_list,
&panic_blk);
cancel_delayed_work(&dogwork_struct);
/* may be suspended after the first write above */
__raw_writel(0, msm_tmr0_base + WDT0_EN);
printk(KERN_INFO "MSM Watchdog deactivated.\n");
}
break;
default:
runtime_disable = old_val;
ret = -EINVAL;
break;
}
done:
mutex_unlock(&disable_lock);
return ret;
}
unsigned min_slack_ticks = UINT_MAX;
unsigned long long min_slack_ns = ULLONG_MAX;
void pet_watchdog(void)
{
int slack;
unsigned long long time_ns;
unsigned long long slack_ns;
unsigned long long bark_time_ns = bark_time * 1000000ULL;
if (!enable)
return;
slack = __raw_readl(msm_tmr0_base + WDT0_STS) >> 3;
slack = ((bark_time*WDT_HZ)/1000) - slack;
if (slack < min_slack_ticks)
min_slack_ticks = slack;
__raw_writel(1, msm_tmr0_base + WDT0_RST);
time_ns = sched_clock();
slack_ns = (last_pet + bark_time_ns) - time_ns;
if (slack_ns < min_slack_ns)
min_slack_ns = slack_ns;
last_pet = time_ns;
}
static void pet_watchdog_work(struct work_struct *work)
{
pet_watchdog();
if (enable)
schedule_delayed_work_on(0, &dogwork_struct, delay_time);
}
static int msm_watchdog_remove(struct platform_device *pdev)
{
if (enable) {
__raw_writel(0, msm_tmr0_base + WDT0_EN);
mb();
if (has_vic) {
free_irq(WDT0_ACCSCSSNBARK_INT, 0);
} else {
disable_percpu_irq(WDT0_ACCSCSSNBARK_INT);
if (!appsbark_fiq) {
free_percpu_irq(WDT0_ACCSCSSNBARK_INT,
percpu_pdata);
free_percpu(percpu_pdata);
}
}
enable = 0;
/* In case we got suspended mid-exit */
__raw_writel(0, msm_tmr0_base + WDT0_EN);
}
printk(KERN_INFO "MSM Watchdog Exit - Deactivated\n");
return 0;
}
static irqreturn_t wdog_bark_handler(int irq, void *dev_id)
{
unsigned long nanosec_rem;
unsigned long long t = sched_clock();
struct task_struct *tsk;
nanosec_rem = do_div(t, 1000000000);
printk(KERN_INFO "Watchdog bark! Now = %lu.%06lu\n", (unsigned long) t,
nanosec_rem / 1000);
nanosec_rem = do_div(last_pet, 1000000000);
printk(KERN_INFO "Watchdog last pet at %lu.%06lu\n", (unsigned long)
last_pet, nanosec_rem / 1000);
if (print_all_stacks) {
/* Suspend wdog until all stacks are printed */
msm_watchdog_suspend(NULL);
printk(KERN_INFO "Stack trace dump:\n");
for_each_process(tsk) {
printk(KERN_INFO "\nPID: %d, Name: %s\n",
tsk->pid, tsk->comm);
show_stack(tsk, NULL);
}
msm_watchdog_resume(NULL);
}
panic("Apps watchdog bark received!");
return IRQ_HANDLED;
}
#define SCM_SET_REGSAVE_CMD 0x2
static void configure_bark_dump(void)
{
int ret;
struct {
unsigned addr;
int len;
} cmd_buf;
if (!appsbark) {
scm_regsave = (void *)__get_free_page(GFP_KERNEL);
if (scm_regsave) {
cmd_buf.addr = __pa(scm_regsave);
cmd_buf.len = PAGE_SIZE;
ret = scm_call(SCM_SVC_UTIL, SCM_SET_REGSAVE_CMD,
&cmd_buf, sizeof(cmd_buf), NULL, 0);
if (ret)
pr_err("Setting register save address failed.\n"
"Registers won't be dumped on a dog "
"bite\n");
} else {
pr_err("Allocating register save space failed\n"
"Registers won't be dumped on a dog bite\n");
/*
* No need to bail if allocation fails. Simply don't
* send the command, and the secure side will reset
* without saving registers.
*/
}
}
}
static void init_watchdog_work(struct work_struct *work)
{
u64 timeout = (bark_time * WDT_HZ)/1000;
configure_bark_dump();
__raw_writel(timeout, msm_tmr0_base + WDT0_BARK_TIME);
__raw_writel(timeout + 3*WDT_HZ, msm_tmr0_base + WDT0_BITE_TIME);
schedule_delayed_work_on(0, &dogwork_struct, delay_time);
atomic_notifier_chain_register(&panic_notifier_list,
&panic_blk);
__raw_writel(1, msm_tmr0_base + WDT0_EN);
__raw_writel(1, msm_tmr0_base + WDT0_RST);
last_pet = sched_clock();
if (!has_vic)
enable_percpu_irq(WDT0_ACCSCSSNBARK_INT, IRQ_TYPE_EDGE_RISING);
printk(KERN_INFO "MSM Watchdog Initialized\n");
return;
}
struct fiq_handler wdog_fh = {
.name = MODULE_NAME,
};
static int msm_watchdog_probe(struct platform_device *pdev)
{
struct msm_watchdog_pdata *pdata = pdev->dev.platform_data;
int ret;
void *stack;
if (!enable || !pdata || !pdata->pet_time || !pdata->bark_time) {
printk(KERN_INFO "MSM Watchdog Not Initialized\n");
return -ENODEV;
}
bark_time = pdata->bark_time;
has_vic = pdata->has_vic;
if (!pdata->has_secure) {
appsbark = 1;
appsbark_fiq = pdata->use_kernel_fiq;
}
msm_tmr0_base = msm_timer_get_timer0_base();
if (has_vic) {
ret = request_irq(WDT0_ACCSCSSNBARK_INT, wdog_bark_handler, 0,
"apps_wdog_bark", NULL);
if (ret)
return ret;
} else if (appsbark_fiq) {
claim_fiq(&wdog_fh);
set_fiq_handler(&msm_wdog_fiq_start, msm_wdog_fiq_length);
stack = (void *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
if (!stack) {
pr_info("No free pages available - %s fails\n",
__func__);
return -ENOMEM;
}
msm_wdog_fiq_setup(stack);
gic_set_irq_secure(WDT0_ACCSCSSNBARK_INT);
} else {
percpu_pdata = alloc_percpu(struct msm_watchdog_pdata *);
if (!percpu_pdata) {
pr_err("%s: memory allocation failed for percpu data\n",
__func__);
return -ENOMEM;
}
*__this_cpu_ptr(percpu_pdata) = pdata;
/* Must request irq before sending scm command */
ret = request_percpu_irq(WDT0_ACCSCSSNBARK_INT,
wdog_bark_handler, "apps_wdog_bark", percpu_pdata);
if (ret) {
free_percpu(percpu_pdata);
return ret;
}
}
/*
* This is only temporary till SBLs turn on the XPUs
* This initialization will be done in SBLs on a later releases
*/
if (cpu_is_msm9615())
__raw_writel(0xF, MSM_TCSR_BASE + TCSR_WDT_CFG);
if (pdata->needs_expired_enable)
__raw_writel(0x1, MSM_CLK_CTL_BASE + 0x3820);
delay_time = msecs_to_jiffies(pdata->pet_time);
schedule_work_on(0, &init_dogwork_struct);
return 0;
}
static const struct dev_pm_ops msm_watchdog_dev_pm_ops = {
.suspend_noirq = msm_watchdog_suspend,
.resume_noirq = msm_watchdog_resume,
};
static struct platform_driver msm_watchdog_driver = {
.probe = msm_watchdog_probe,
.remove = msm_watchdog_remove,
.driver = {
.name = MODULE_NAME,
.owner = THIS_MODULE,
.pm = &msm_watchdog_dev_pm_ops,
},
};
static int init_watchdog(void)
{
return platform_driver_register(&msm_watchdog_driver);
}
late_initcall(init_watchdog);
MODULE_DESCRIPTION("MSM Watchdog Driver");
MODULE_VERSION("1.0");
MODULE_LICENSE("GPL v2");