From: Jan Kiszka Date: Mon, 21 Feb 2022 16:22:38 +0000 (+0100) Subject: watchdog: rti_wdt: Fix calculation and evaluation of preset heartbeat X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c83f643878388d468e0a674ac9502d4080499646;p=linux.git watchdog: rti_wdt: Fix calculation and evaluation of preset heartbeat This ensures that the same value is read back as was eventually programmed when using seconds as accuracy. Even then, comparing the more precise heartbeat_ms against heartbeat in seconds will almost never provide a match and will needlessly raise a warning. Fix by comparing apples to apples. Tested in combination with U-Boot as watchdog starter. Signed-off-by: Jan Kiszka Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/6a4b54ac-9588-e172-c4c7-b91d524a851e@siemens.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c index db843f8258602..35f3c396a2ff3 100644 --- a/drivers/watchdog/rti_wdt.c +++ b/drivers/watchdog/rti_wdt.c @@ -253,6 +253,7 @@ static int rti_wdt_probe(struct platform_device *pdev) } if (readl(wdt->base + RTIDWDCTRL) == WDENABLE_KEY) { + int preset_heartbeat; u32 time_left_ms; u64 heartbeat_ms; u32 wsize; @@ -263,11 +264,12 @@ static int rti_wdt_probe(struct platform_device *pdev) heartbeat_ms <<= WDT_PRELOAD_SHIFT; heartbeat_ms *= 1000; do_div(heartbeat_ms, wdt->freq); - if (heartbeat_ms != heartbeat * 1000) + preset_heartbeat = heartbeat_ms + 500; + preset_heartbeat /= 1000; + if (preset_heartbeat != heartbeat) dev_warn(dev, "watchdog already running, ignoring heartbeat config!\n"); - heartbeat = heartbeat_ms; - heartbeat /= 1000; + heartbeat = preset_heartbeat; wsize = readl(wdt->base + RTIWWDSIZECTRL); ret = rti_wdt_setup_hw_hb(wdd, wsize);