Signed-off-by: Simon Arlott <simon@xxxxxxxxxxx>
---
arch/mips/bcm63xx/prom.c | 1 +
arch/mips/bcm63xx/setup.c | 1 +
arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h | 22 --
drivers/watchdog/Kconfig | 4 +-
drivers/watchdog/bcm63xx_wdt.c | 420 +++++++++++-----------
include/linux/bcm63xx_wdt.h | 22 ++
6 files changed, 244 insertions(+), 226 deletions(-)
create mode 100644 include/linux/bcm63xx_wdt.h
diff --git a/arch/mips/bcm63xx/prom.c b/arch/mips/bcm63xx/prom.c
index 7019e29..ba8b354 100644
--- a/arch/mips/bcm63xx/prom.c
+++ b/arch/mips/bcm63xx/prom.c
@@ -17,6 +17,7 @@
#include <bcm63xx_cpu.h>
#include <bcm63xx_io.h>
#include <bcm63xx_regs.h>
+#include <linux/bcm63xx_wdt.h>
void __init prom_init(void)
{
diff --git a/arch/mips/bcm63xx/setup.c b/arch/mips/bcm63xx/setup.c
index 240fb4f..6abf364 100644
--- a/arch/mips/bcm63xx/setup.c
+++ b/arch/mips/bcm63xx/setup.c
@@ -21,6 +21,7 @@
#include <bcm63xx_regs.h>
#include <bcm63xx_io.h>
#include <bcm63xx_gpio.h>
+#include <linux/bcm63xx_wdt.h>
void bcm63xx_machine_halt(void)
{
diff --git a/arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h b/arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h
index 5035f09..16a745b 100644
--- a/arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h
+++ b/arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h
@@ -441,28 +441,6 @@
/*************************************************************************
- * _REG relative to RSET_WDT
- *************************************************************************/
-
-/* Watchdog default count register */
-#define WDT_DEFVAL_REG 0x0
-
-/* Watchdog control register */
-#define WDT_CTL_REG 0x4
-
-/* Watchdog control register constants */
-#define WDT_START_1 (0xff00)
-#define WDT_START_2 (0x00ff)
-#define WDT_STOP_1 (0xee00)
-#define WDT_STOP_2 (0x00ee)
-
-/* Watchdog reset length register */
-#define WDT_RSTLEN_REG 0x8
-
-/* Watchdog soft reset register (BCM6328 only) */
-#define WDT_SOFTRESET_REG 0xc
-
-/*************************************************************************
* _REG relative to RSET_GPIO
*************************************************************************/
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 7a8a6c6..0c50add 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1272,7 +1272,9 @@ config OCTEON_WDT
config BCM63XX_WDT
tristate "Broadcom BCM63xx hardware watchdog"
- depends on BCM63XX
+ depends on BCM63XX || BMIPS_GENERIC
+ select WATCHDOG_CORE
+ select BCM6345_L2_TIMER_IRQ if BMIPS_GENERIC
help
Watchdog driver for the built in watchdog hardware in Broadcom
BCM63xx SoC.
diff --git a/drivers/watchdog/bcm63xx_wdt.c b/drivers/watchdog/bcm63xx_wdt.c
index ab26fd9..fff92d0 100644
--- a/drivers/watchdog/bcm63xx_wdt.c
+++ b/drivers/watchdog/bcm63xx_wdt.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 2007, Miguel Gaio <miguel.gaio@xxxxxxxxx>
* Copyright (C) 2008, Florian Fainelli <florian@xxxxxxxxxxx>
+ * Copyright 2015 Simon Arlott
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -12,235 +13,165 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/bitops.h>
+#include <linux/bcm63xx_wdt.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
#include <linux/errno.h>
-#include <linux/fs.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
-#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/spinlock.h>
#include <linux/types.h>
-#include <linux/uaccess.h>
#include <linux/watchdog.h>
-#include <linux/timer.h>
-#include <linux/jiffies.h>
-#include <linux/interrupt.h>
-#include <linux/ptrace.h>
-#include <linux/resource.h>
-#include <linux/platform_device.h>
-#include <bcm63xx_cpu.h>
-#include <bcm63xx_io.h>
-#include <bcm63xx_regs.h>
-#include <bcm63xx_timer.h>
+#ifdef CONFIG_BCM63XX
+# include <bcm63xx_regs.h>
+# include <bcm63xx_timer.h>
+#endif
#define PFX KBUILD_MODNAME
-#define WDT_HZ 50000000 /* Fclk */
-#define WDT_DEFAULT_TIME 30 /* seconds */
-#define WDT_MAX_TIME 256 /* seconds */
-
-static struct {
- void __iomem *regs;
- struct timer_list timer;
- unsigned long inuse;
- atomic_t ticks;
-} bcm63xx_wdt_device;
-
-static int expect_close;
-
-static int wdt_time = WDT_DEFAULT_TIME;
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-/* HW functions */
-static void bcm63xx_wdt_hw_start(void)
-{
- bcm_writel(0xfffffffe, bcm63xx_wdt_device.regs + WDT_DEFVAL_REG);
- bcm_writel(WDT_START_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
- bcm_writel(WDT_START_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
-}
-
-static void bcm63xx_wdt_hw_stop(void)
-{
- bcm_writel(WDT_STOP_1, bcm63xx_wdt_device.regs + WDT_CTL_REG);
- bcm_writel(WDT_STOP_2, bcm63xx_wdt_device.regs + WDT_CTL_REG);
-}
-
-static void bcm63xx_wdt_isr(void *data)
-{
- struct pt_regs *regs = get_irq_regs();
-
- die(PFX " fire", regs);
-}
-
-static void bcm63xx_timer_tick(unsigned long unused)
-{
- if (!atomic_dec_and_test(&bcm63xx_wdt_device.ticks)) {
- bcm63xx_wdt_hw_start();
- mod_timer(&bcm63xx_wdt_device.timer, jiffies + HZ);
- } else
- pr_crit("watchdog will restart system\n");
-}
-
-static void bcm63xx_wdt_pet(void)
-{
- atomic_set(&bcm63xx_wdt_device.ticks, wdt_time);
-}
-
-static void bcm63xx_wdt_start(void)
-{
- bcm63xx_wdt_pet();
- bcm63xx_timer_tick(0);
-}
+struct bcm63xx_wdt_hw {
+ raw_spinlock_t lock;
+ void __iomem *base;
+ struct clk *clk;
+ u32 clock_hz;
+ int irq;
+ bool running;
+};
-static void bcm63xx_wdt_pause(void)
+static int bcm63xx_wdt_start(struct watchdog_device *wdd)
{
- del_timer_sync(&bcm63xx_wdt_device.timer);
- bcm63xx_wdt_hw_stop();
+ struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&hw->lock, flags);
+ __raw_writel(wdd->timeout * hw->clock_hz, hw->base + WDT_DEFVAL_REG);
+ __raw_writel(WDT_START_1, hw->base + WDT_CTL_REG);
+ __raw_writel(WDT_START_2, hw->base + WDT_CTL_REG);
+ hw->running = true;
+ raw_spin_unlock_irqrestore(&hw->lock, flags);
+ return 0;
}
-static int bcm63xx_wdt_settimeout(int new_time)
+static int bcm63xx_wdt_stop(struct watchdog_device *wdd)
{
- if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
- return -EINVAL;
-
- wdt_time = new_time;
-
+ struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&hw->lock, flags);
+ __raw_writel(WDT_STOP_1, hw->base + WDT_CTL_REG);
+ __raw_writel(WDT_STOP_2, hw->base + WDT_CTL_REG);
+ hw->running = false;
+ raw_spin_unlock_irqrestore(&hw->lock, flags);
return 0;
}
-static int bcm63xx_wdt_open(struct inode *inode, struct file *file)
+static unsigned int bcm63xx_wdt_get_timeleft(struct watchdog_device *wdd)
{
- if (test_and_set_bit(0, &bcm63xx_wdt_device.inuse))
- return -EBUSY;
-
- bcm63xx_wdt_start();
- return nonseekable_open(inode, file);
+ struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd);
+ unsigned long flags;
+ u32 val;
+
+ raw_spin_lock_irqsave(&hw->lock, flags);
+ val = __raw_readl(hw->base + WDT_CTL_REG);
+ val /= hw->clock_hz;
+ raw_spin_unlock_irqrestore(&hw->lock, flags);
+ return val;
}
-static int bcm63xx_wdt_release(struct inode *inode, struct file *file)
+static int bcm63xx_wdt_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
{
- if (expect_close == 42)
- bcm63xx_wdt_pause();
- else {
- pr_crit("Unexpected close, not stopping watchdog!\n");
- bcm63xx_wdt_start();
- }
- clear_bit(0, &bcm63xx_wdt_device.inuse);
- expect_close = 0;
- return 0;
+ wdd->timeout = timeout;
+ return bcm63xx_wdt_start(wdd);
}
-static ssize_t bcm63xx_wdt_write(struct file *file, const char *data,
- size_t len, loff_t *ppos)
+/* The watchdog interrupt occurs when half the timeout is remaining */
+#ifdef CONFIG_BCM63XX
+static void bcm63xx_wdt_interrupt(void *data)
+#else
+static irqreturn_t bcm63xx_wdt_interrupt(int irq, void *data)
+#endif
{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- /* In case it was set long ago */
- expect_close = 0;
-
- for (i = 0; i != len; i++) {
- char c;
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- expect_close = 42;
- }
+ struct watchdog_device *wdd = data;
+ struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&hw->lock, flags);
+ if (!hw->running) {
+ /* Oops */
+ __raw_writel(WDT_STOP_1, hw->base + WDT_CTL_REG);
+ __raw_writel(WDT_STOP_2, hw->base + WDT_CTL_REG);
+ } else {
+ u32 timeleft = __raw_readl(hw->base + WDT_CTL_REG);
+ u32 ms;
+
+ if (timeleft >= 2) {
+ /* The only way to stop this interrupt without masking
+ * the whole timer interrupt or disrupting the intended
+ * behaviour of the watchdog is to restart the watchdog
+ * with the remaining time value so that the interrupt
+ * occurs again at 1/4th, 1/8th, etc. of the timeout
+ * until we reboot.
+ *
+ * This is done with a lock held in case userspace is
+ * restarting the watchdog on another CPU.
+ */
+ __raw_writel(timeleft, hw->base + WDT_DEFVAL_REG);
+ __raw_writel(WDT_START_1, hw->base + WDT_CTL_REG);
+ __raw_writel(WDT_START_2, hw->base + WDT_CTL_REG);
+ } else {
+ /* The watchdog cannot be started with a time of less
+ * than 2 ticks (it won't fire).
+ */
+ die(PFX ": watchdog timer expired\n", get_irq_regs());
}
- bcm63xx_wdt_pet();
- }
- return len;
-}
-
-static struct watchdog_info bcm63xx_wdt_info = {
- .identity = PFX,
- .options = WDIOF_SETTIMEOUT |
- WDIOF_KEEPALIVEPING |
- WDIOF_MAGICCLOSE,
-};
-
-
-static long bcm63xx_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- int new_value, retval = -EINVAL;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user(argp, &bcm63xx_wdt_info,
- sizeof(bcm63xx_wdt_info)) ? -EFAULT : 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, p);
-
- case WDIOC_SETOPTIONS:
- if (get_user(new_value, p))
- return -EFAULT;
-
- if (new_value & WDIOS_DISABLECARD) {
- bcm63xx_wdt_pause();
- retval = 0;
- }
- if (new_value & WDIOS_ENABLECARD) {
- bcm63xx_wdt_start();
- retval = 0;
- }
-
- return retval;
-
- case WDIOC_KEEPALIVE:
- bcm63xx_wdt_pet();
- return 0;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(new_value, p))
- return -EFAULT;
-
- if (bcm63xx_wdt_settimeout(new_value))
- return -EINVAL;
-
- bcm63xx_wdt_pet();
-
- case WDIOC_GETTIMEOUT:
- return put_user(wdt_time, p);
-
- default:
- return -ENOTTY;
+ ms = timeleft / (hw->clock_hz / 1000);
+ dev_alert(wdd->dev, "warning timer fired, reboot in %ums", ms);
}
+ raw_spin_unlock_irqrestore(&hw->lock, flags);
+#ifndef CONFIG_BCM63XX
+ return IRQ_HANDLED;
+#endif
}
-static const struct file_operations bcm63xx_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = bcm63xx_wdt_write,
- .unlocked_ioctl = bcm63xx_wdt_ioctl,
- .open = bcm63xx_wdt_open,
- .release = bcm63xx_wdt_release,
+static struct watchdog_ops bcm63xx_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = bcm63xx_wdt_start,
+ .stop = bcm63xx_wdt_stop,
+ .get_timeleft = bcm63xx_wdt_get_timeleft,
+ .set_timeout = bcm63xx_wdt_set_timeout,
};
-static struct miscdevice bcm63xx_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &bcm63xx_wdt_fops,
+static const struct watchdog_info bcm63xx_wdt_info = {
+ .options = WDIOC_GETTIMELEFT | WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "BCM63xx Watchdog",
};
-
static int bcm63xx_wdt_probe(struct platform_device *pdev)
{
- int ret;
+ struct bcm63xx_wdt_hw *hw;
+ struct watchdog_device *wdd;
struct resource *r;
+ unsigned int timeleft;
+ int ret;
- setup_timer(&bcm63xx_wdt_device.timer, bcm63xx_timer_tick, 0L);
+ hw = devm_kzalloc(&pdev->dev, sizeof(*hw), GFP_KERNEL);
+ wdd = devm_kzalloc(&pdev->dev, sizeof(*wdd), GFP_KERNEL);
+ if (!hw || !wdd)
+ return -ENOMEM;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!r) {
@@ -248,63 +179,145 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev)
return -ENODEV;
}
- bcm63xx_wdt_device.regs = devm_ioremap_nocache(&pdev->dev, r->start,
- resource_size(r));
- if (!bcm63xx_wdt_device.regs) {
+ hw->base = devm_ioremap_nocache(&pdev->dev, r->start, resource_size(r));
+ if (!hw->base) {
dev_err(&pdev->dev, "failed to remap I/O resources\n");
return -ENXIO;
}
- ret = bcm63xx_timer_register(TIMER_WDT_ID, bcm63xx_wdt_isr, NULL);
- if (ret < 0) {
- dev_err(&pdev->dev, "failed to register wdt timer isr\n");
+#ifdef CONFIG_BCM63XX
+ hw->clk = devm_clk_get(&pdev->dev, "periph");
+#else
+ hw->clk = devm_clk_get(&pdev->dev, NULL);
+#endif
+ if (IS_ERR(hw->clk)) {
+ dev_err(&pdev->dev, "unable to request clock\n");
+ return PTR_ERR(hw->clk);
+ }
+
+ hw->clock_hz = clk_get_rate(hw->clk);
+ if (!hw->clock_hz) {
+ dev_err(&pdev->dev, "unable to fetch clock rate\n");
+ return -EINVAL;
+ }
+
+ ret = clk_prepare_enable(hw->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to enable clock\n");
return ret;
}
- if (bcm63xx_wdt_settimeout(wdt_time)) {
- bcm63xx_wdt_settimeout(WDT_DEFAULT_TIME);
- dev_info(&pdev->dev,
- ": wdt_time value must be 1 <= wdt_time <= 256, using %d\n",
- wdt_time);
+ raw_spin_lock_init(&hw->lock);
+ hw->running = false;
+
+ wdd->parent = &pdev->dev;
+ wdd->ops = &bcm63xx_wdt_ops;
+ wdd->info = &bcm63xx_wdt_info;
+ wdd->min_timeout = 1;
+ wdd->max_timeout = 0xffffffff / hw->clock_hz;
+ wdd->timeout = min(30U, wdd->max_timeout);
+
+ watchdog_set_drvdata(wdd, hw);
+ platform_set_drvdata(pdev, wdd);
+
+ watchdog_init_timeout(wdd, 0, &pdev->dev);
+ watchdog_set_nowayout(wdd, nowayout);
+
+ timeleft = bcm63xx_wdt_get_timeleft(wdd);
+ if (timeleft > 0)
+ hw->running = true;
+
+#ifdef CONFIG_BCM63XX
+ ret = bcm63xx_timer_register(TIMER_WDT_ID, bcm63xx_wdt_interrupt, wdd);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register with bcm63xx_timer\n");
+ goto disable_clk;
}
+ hw->irq = 0;
+#endif
- ret = misc_register(&bcm63xx_wdt_miscdev);
+ ret = watchdog_register_device(wdd);
if (ret < 0) {
dev_err(&pdev->dev, "failed to register watchdog device\n");
+#ifdef CONFIG_BCM63XX
goto unregister_timer;
+#else
+ goto disable_clk;
+#endif
}
- dev_info(&pdev->dev, " started, timer margin: %d sec\n",
- WDT_DEFAULT_TIME);
+#ifndef CONFIG_BCM63XX
+ hw->irq = platform_get_irq(pdev, 0);
+ if (hw->irq) {
+ ret = devm_request_irq(&pdev->dev, hw->irq,
+ bcm63xx_wdt_interrupt, IRQF_TIMER,
+ dev_name(&pdev->dev), wdd);
+ if (ret)
+ hw->irq = 0;
+ }
+#endif
+
+ if (hw->irq) {
+ dev_info(&pdev->dev,
+ "%s at MMIO 0x%p (irq = %d, timeout = %us, max_timeout = %us)",
+ dev_name(wdd->dev), hw->base, hw->irq,
+ wdd->timeout, wdd->max_timeout);
+ } else {
+ dev_info(&pdev->dev,
+ "%s at MMIO 0x%p (timeout = %us, max_timeout = %us)",
+ dev_name(wdd->dev), hw->base,
+ wdd->timeout, wdd->max_timeout);
+ }
+ if (timeleft > 0)
+ dev_alert(wdd->dev, "running, reboot in %us\n", timeleft);
return 0;
+#ifdef CONFIG_BCM63XX
unregister_timer:
bcm63xx_timer_unregister(TIMER_WDT_ID);
+#endif
+disable_clk:
+ clk_disable(hw->clk);
return ret;
}
static int bcm63xx_wdt_remove(struct platform_device *pdev)
{
- if (!nowayout)
- bcm63xx_wdt_pause();
+ struct watchdog_device *wdd = platform_get_drvdata(pdev);
+ struct bcm63xx_wdt_hw *hw = watchdog_get_drvdata(wdd);
- misc_deregister(&bcm63xx_wdt_miscdev);
+ if (hw->irq)
+ devm_free_irq(&pdev->dev, hw->irq, wdd);
+
+#ifdef CONFIG_BCM63XX
bcm63xx_timer_unregister(TIMER_WDT_ID);
+#endif
+ watchdog_unregister_device(wdd);
+ clk_disable(hw->clk);
return 0;
}
static void bcm63xx_wdt_shutdown(struct platform_device *pdev)
{
- bcm63xx_wdt_pause();
+ struct watchdog_device *wdd = platform_get_drvdata(pdev);
+
+ bcm63xx_wdt_stop(wdd);
}
+static const struct of_device_id bcm63xx_wdt_dt_ids[] = {
+ { .compatible = "brcm,bcm6345-wdt" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, bcm63xx_wdt_dt_ids);
+
static struct platform_driver bcm63xx_wdt_driver = {
.probe = bcm63xx_wdt_probe,
.remove = bcm63xx_wdt_remove,
.shutdown = bcm63xx_wdt_shutdown,
.driver = {
.name = "bcm63xx-wdt",
+ .of_match_table = bcm63xx_wdt_dt_ids,
}
};
@@ -312,6 +325,7 @@ module_platform_driver(bcm63xx_wdt_driver);
MODULE_AUTHOR("Miguel Gaio <miguel.gaio@xxxxxxxxx>");
MODULE_AUTHOR("Florian Fainelli <florian@xxxxxxxxxxx>");
+MODULE_AUTHOR("Simon Arlott");
MODULE_DESCRIPTION("Driver for the Broadcom BCM63xx SoC watchdog");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:bcm63xx-wdt");
diff --git a/include/linux/bcm63xx_wdt.h b/include/linux/bcm63xx_wdt.h
new file mode 100644
index 0000000..ef4792e
--- /dev/null
+++ b/include/linux/bcm63xx_wdt.h
@@ -0,0 +1,22 @@
+#ifndef LINUX_BCM63XX_WDT_H_
+#define LINUX_BCM63XX_WDT_H_
+
+/* Watchdog default count register */
+#define WDT_DEFVAL_REG 0x0
+
+/* Watchdog control register */
+#define WDT_CTL_REG 0x4
+
+/* Watchdog control register constants */
+#define WDT_START_1 (0xff00)
+#define WDT_START_2 (0x00ff)
+#define WDT_STOP_1 (0xee00)
+#define WDT_STOP_2 (0x00ee)
+
+/* Watchdog reset length register (in clock ticks) */
+#define WDT_RSTLEN_REG 0x8
+
+/* Watchdog soft reset register (BCM6328 only) */
+#define WDT_SOFTRESET_REG 0xc
+
+#endif
