drivers: watchdog: qcom: Add timeout configuration support in watchdog
This patch enhances the Qualcomm watchdog driver by introducing
support for dynamic timeout configuration. Specifically:
- Calculates and sets the bark and bite timeout values based on
the clock rate and the requested timeout in milliseconds.
- Adds retrieval of the watchdog clock rate during probe using
the common clock framework.
- Adds a default timeout value for ARCH_SNAPDRAGON
in WATCHDOG_TIMEOUT_MSECS.
These changes improve the configurability and accuracy of the
watchdog timer on Qualcomm platforms.
This work builds upon the previous submission:
https://lore.kernel.org/all/20250422-b4-qcom-wdt-v3-1-730d4d5a858d@paulsajna.com/
Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250527124926.128413-1-balaji.selvanathan@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
index 3601ba9..adbb5aa 100644
--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -13,6 +13,7 @@
#include <dm.h>
#include <dm/device_compat.h>
#include <wdt.h>
+#include <clk.h>
#include <asm/io.h>
@@ -30,6 +31,7 @@
struct qcom_wdt {
void __iomem *base;
+ ulong clk_rate;
const u32 *layout;
};
@@ -53,10 +55,14 @@
int qcom_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
{
struct qcom_wdt *wdt = dev_get_priv(dev);
+ ulong bark_timeout_s = ((timeout_ms - 1) * wdt->clk_rate) / 1000;
+ ulong bite_timeout_s = (timeout_ms * wdt->clk_rate) / 1000;
writel(0, wdt_addr(wdt, WDT_EN));
- writel(1, wdt_addr(wdt, WDT_RST));
- writel(1, wdt_addr(wdt, WDT_EN));
+ writel(BIT(0), wdt_addr(wdt, WDT_RST));
+ writel(bark_timeout_s, wdt_addr(wdt, WDT_BARK_TIME));
+ writel(bite_timeout_s, wdt_addr(wdt, WDT_BITE_TIME));
+ writel(BIT(0), wdt_addr(wdt, WDT_EN));
if (readl(wdt_addr(wdt, WDT_EN)) != 1) {
dev_err(dev, "Failed to enable Qualcomm watchdog!\n");
return -EIO;
@@ -87,12 +93,26 @@
static int qcom_wdt_probe(struct udevice *dev)
{
+ struct clk clk;
+ long rate;
+ int ret;
+
struct qcom_wdt *wdt = dev_get_priv(dev);
struct qcom_wdt_match_data *data = (void *)dev_get_driver_data(dev);
wdt->base = dev_read_addr_ptr(dev);
wdt->layout = data->offset;
+ ret = clk_get_by_index(dev, 0, &clk);
+ if (ret)
+ return ret;
+
+ rate = clk_get_rate(&clk);
+ if (rate <= 0)
+ return rate < 0 ? (int)rate : -EINVAL;
+
+ wdt->clk_rate = (ulong)rate;
+
return 0;
}