diff mbox series

[4.19.y-cip] watchdog: renesas_wdt: support handover from bootloader

Message ID 20250221165755.357838-1-paul.barker.ct@bp.renesas.com (mailing list archive)
State New
Headers show
Series [4.19.y-cip] watchdog: renesas_wdt: support handover from bootloader | expand

Commit Message

Paul Barker Feb. 21, 2025, 4:57 p.m. UTC 
From: Wolfram Sang <wsa+renesas@sang-engineering.com>

commit 962085a2bb823d8c88c6bc706c654648407e6408 upstream.

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 <wsa+renesas@sang-engineering.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200908095615.31376-1-wsa+renesas@sang-engineering.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
---
 drivers/watchdog/renesas_wdt.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 24963979163a..3cdfaeae15ec 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -198,6 +198,7 @@  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;
@@ -218,8 +219,8 @@  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) {
@@ -259,6 +260,13 @@  static int rwdt_probe(struct platform_device *pdev)
 	if (ret)
 		dev_warn(dev, "Specified timeout value invalid, using default\n");
 
+	/* 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;