From 962085a2bb823d8c88c6bc706c654648407e6408 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Tue, 8 Sep 2020 11:56:15 +0200 Subject: watchdog: renesas_wdt: support handover from bootloader Support an already running watchdog by checking its enable bit and set up the status accordingly before registering the device. Signed-off-by: Wolfram Sang Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200908095615.31376-1-wsa+renesas@sang-engineering.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/renesas_wdt.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c index 00662a8e039c..47fce4de0110 100644 --- a/drivers/watchdog/renesas_wdt.c +++ b/drivers/watchdog/renesas_wdt.c @@ -194,6 +194,7 @@ static int rwdt_probe(struct platform_device *pdev) struct clk *clk; unsigned long clks_per_sec; int ret, i; + u8 csra; if (rwdt_blacklisted(dev)) return -ENODEV; @@ -213,8 +214,8 @@ static int rwdt_probe(struct platform_device *pdev) pm_runtime_enable(dev); pm_runtime_get_sync(dev); priv->clk_rate = clk_get_rate(clk); - priv->wdev.bootstatus = (readb_relaxed(priv->base + RWTCSRA) & - RWTCSRA_WOVF) ? WDIOF_CARDRESET : 0; + csra = readb_relaxed(priv->base + RWTCSRA); + priv->wdev.bootstatus = csra & RWTCSRA_WOVF ? WDIOF_CARDRESET : 0; pm_runtime_put(dev); if (!priv->clk_rate) { @@ -252,6 +253,13 @@ static int rwdt_probe(struct platform_device *pdev) /* This overrides the default timeout only if DT configuration was found */ watchdog_init_timeout(&priv->wdev, 0, dev); + /* Check if FW enabled the watchdog */ + if (csra & RWTCSRA_TME) { + /* Ensure properly initialized dividers */ + rwdt_start(&priv->wdev); + set_bit(WDOG_HW_RUNNING, &priv->wdev.status); + } + ret = watchdog_register_device(&priv->wdev); if (ret < 0) goto out_pm_disable; -- cgit v1.2.3