On 11/25/24 23:36, A. Sverdlin wrote:
From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
According to AM62x TRM WDT period is (RTIDWDPRLD + 1) * (2^13) / RTICLK1,
Fix the heartbeat recovery. In practice this doesn't affect rounded
heatbeat in seconds, but it does correct 4% of error in milliseconds,
for, say, default 60s heartbeat. This affects last_ping calculation.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/watchdog/rti_wdt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
index 563d842014dfb..0416e54b17edb 100644
--- a/drivers/watchdog/rti_wdt.c
+++ b/drivers/watchdog/rti_wdt.c
@@ -273,7 +273,8 @@ static int rti_wdt_probe(struct platform_device *pdev)
set_bit(WDOG_HW_RUNNING, &wdd->status);
time_left_ms = rti_wdt_get_timeleft_ms(wdd);
- heartbeat_ms = readl(wdt->base + RTIDWDPRLD);
+ /* AM62x TRM: texp = (RTIDWDPRLD + 1) * (2^13) / RTICLK1 */
+ heartbeat_ms = readl(wdt->base + RTIDWDPRLD) + 1;
heartbeat_ms <<= WDT_PRELOAD_SHIFT;
heartbeat_ms *= 1000;
do_div(heartbeat_ms, wdt->freq);
