Warn when the device is registered if the hardware watchdog is currently running and report the remaining time left.
Signed-off-by: Simon Arlott <si...@fire.lp0.eu> --- drivers/watchdog/bcm63xx_wdt.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/bcm63xx_wdt.c b/drivers/watchdog/bcm63xx_wdt.c index ab4a794..2312dc2 100644 --- a/drivers/watchdog/bcm63xx_wdt.c +++ b/drivers/watchdog/bcm63xx_wdt.c @@ -14,6 +14,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/clk.h> +#include <linux/delay.h> #include <linux/errno.h> #include <linux/io.h> #include <linux/kernel.h> @@ -159,6 +160,8 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) struct bcm63xx_wdt_hw *hw; struct watchdog_device *wdd; struct resource *r; + u32 timeleft1, timeleft2; + unsigned int timeleft; int ret; hw = devm_kzalloc(&pdev->dev, sizeof(*hw), GFP_KERNEL); @@ -199,7 +202,6 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) } raw_spin_lock_init(&hw->lock); - hw->running = false; wdd->parent = &pdev->dev; wdd->ops = &bcm63xx_wdt_ops; @@ -213,6 +215,23 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) watchdog_init_timeout(wdd, 0, &pdev->dev); watchdog_set_nowayout(wdd, nowayout); + /* Compare two reads of the time left value, 2 clock ticks apart */ + rmb(); + timeleft1 = __raw_readl(hw->regs + WDT_CTL_REG); + udelay(DIV_ROUND_UP(1000000, hw->clock_hz / 2)); + /* Ensure the register is read twice */ + rmb(); + timeleft2 = __raw_readl(hw->regs + WDT_CTL_REG); + + /* If the time left is changing, the watchdog is running */ + if (timeleft1 != timeleft2) { + hw->running = true; + timeleft = bcm63xx_wdt_get_timeleft(wdd); + } else { + hw->running = false; + timeleft = 0; + } + ret = watchdog_register_device(wdd); if (ret < 0) { dev_err(&pdev->dev, "failed to register watchdog device\n"); @@ -230,6 +249,8 @@ static int bcm63xx_wdt_probe(struct platform_device *pdev) dev_name(wdd->dev), hw->regs, wdd->timeout, wdd->max_timeout); + if (hw->running) + dev_alert(wdd->dev, "running, reboot in %us\n", timeleft); return 0; unregister_watchdog: -- 2.1.4 -- Simon Arlott -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/