On Thu 05 Sep 09:21 PDT 2019, Jorge Ramirez-Ortiz wrote:
> Use the bark interrupt to notify the bark event. Since the bark and bite
> timeouts are identical, increase the bite timeout by one second so
> that the bark event can be logged to the console.
>
Afaict you should tie the bark to the "pretimeout" in the watchdog
framework , which would allow the user to specify a pretimeout and
configure what should happen at the bark (just a pr_alert() or panic()).
Regards,
Bjorn
> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
> ---
> drivers/watchdog/qcom-wdt.c | 42 ++++++++++++++++++++++++++++++++++---
> 1 file changed, 39 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
> index 7be7f87be28f..5eaf92084b93 100644
> --- a/drivers/watchdog/qcom-wdt.c
> +++ b/drivers/watchdog/qcom-wdt.c
> @@ -10,6 +10,7 @@
> #include <linux/platform_device.h>
> #include <linux/watchdog.h>
> #include <linux/of_device.h>
> +#include <linux/interrupt.h>
>
> enum wdt_reg {
> WDT_RST,
> @@ -41,6 +42,8 @@ struct qcom_wdt {
> unsigned long rate;
> void __iomem *base;
> const u32 *layout;
> + unsigned int irq;
> + const struct device *dev;
> };
>
> static void __iomem *wdt_addr(struct qcom_wdt *wdt, enum wdt_reg reg)
> @@ -54,15 +57,37 @@ struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd)
> return container_of(wdd, struct qcom_wdt, wdd);
> }
>
> +static inline int qcom_wdt_enable(struct qcom_wdt *wdt)
> +{
> + if (wdt->irq < 0)
> + return 1;
> +
> + /* enable timeout with interrupt */
> + return 3;
> +}
> +
> +static irqreturn_t qcom_wdt_irq(int irq, void *cookie)
> +{
> + struct qcom_wdt *wdt = (struct qcom_wdt *) cookie;
> +
> + dev_warn(wdt->dev, "barking, one second countdown to reset\n");
> +
> + return IRQ_HANDLED;
> +}
> +
> static int qcom_wdt_start(struct watchdog_device *wdd)
> {
> struct qcom_wdt *wdt = to_qcom_wdt(wdd);
> + unsigned int bark, bite;
> +
> + bark = wdd->timeout;
> + bite = wdt->irq < 0 ? bark : bark + 1;
>
> writel(0, wdt_addr(wdt, WDT_EN));
> writel(1, wdt_addr(wdt, WDT_RST));
> - writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
> - writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
> - writel(1, wdt_addr(wdt, WDT_EN));
> + writel(bark * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
> + writel(bite * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
> + writel(qcom_wdt_enable(wdt), wdt_addr(wdt, WDT_EN));
> return 0;
> }
>
> @@ -210,10 +235,21 @@ static int qcom_wdt_probe(struct platform_device *pdev)
> wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
> wdt->wdd.parent = dev;
> wdt->layout = regs;
> + wdt->dev = &pdev->dev;
>
> if (readl(wdt_addr(wdt, WDT_STS)) & 1)
> wdt->wdd.bootstatus = WDIOF_CARDRESET;
>
> + wdt->irq = platform_get_irq(pdev, 0);
> + if (wdt->irq >= 0) {
> + ret = devm_request_irq(&pdev->dev, wdt->irq, qcom_wdt_irq,
> + IRQF_TRIGGER_RISING, "wdog_bark", wdt);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to request irq\n");
> + return ret;
> + }
> + }
> +
> /*
> * If 'timeout-sec' unspecified in devicetree, assume a 30 second
> * default, unless the max timeout is less than 30 seconds, then use
> --
> 2.23.0
>
