Hello all,

just found out, that since patch:

commit 1473f6ac882fde8078826ca828aa3494ff98bf08 Author: Prasanthi Chellakumar Prasanthi.Chellakumar@microchip.com Date: Tue Oct 9 11:46:40 2018 -0700

arm: at91: wdt: Convert watchdog driver to dm/dt

Convert the Watchdog driver for AT91SAM9x processors to support the driver model and device tree. Changes "CONFIG_AT91SAM9_WATCHDOG" to new "CONFIG_WDT_AT91" Kconfig option.

Signed-off-by: Prasanthi Chellakumar prasanthi.chellakumar@microchip.com

wdt always triggers really fast on smartweb and taurus board...

A fast look into it, and I see, that at91_wdt_probe() seems not called.

Prasanthi already mentioned to me (offlist), to add

#include <wdt.h>

static struct udevice *watchdog_dev;

#ifdef CONFIG_WDT_AT91 if (uclass_get_device(UCLASS_WDT, 0, &watchdog_dev)) { printf("Cannot find watchdog!\n"); } else { printf("Enabling Watchdog\n"); wdt_start(watchdog_dev, 15, 0); } #endif

into board code. With this patch at91_wdt_probe() is called now.

Digging deeper in it and it seems there are more things broken:

http://git.denx.de/?p=u-boot.git;a=blob;f=drivers/watchdog/at91sam9_wdt.c;h=...

timeout_s in at91_wdt_start() is assumed in seconds, but wdt_start in include/wdt.h states the timeout is in milliseconds :-(

So code goes into the if:

if (timeout_s > WDT_MAX_TIMEOUT || timeout_s < WDT_MIN_TIMEOUT) timeout = priv->timeout;

and sets timeout new, but never converts the new value with WDT_SEC2TICKS() macro, so the wrong value is written into AT91_WDT_MR ... following patch fixes this:

diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c index 81f448322d..c67bed705f 100644 --- a/drivers/watchdog/at91sam9_wdt.c +++ b/drivers/watchdog/at91sam9_wdt.c @@ -48,11 +48,12 @@ struct at91_wdt_priv { static int at91_wdt_start(struct udevice *dev, u64 timeout_s, ulong flags) { struct at91_wdt_priv *priv = dev_get_priv(dev); - u32 timeout = WDT_SEC2TICKS(timeout_s); + u32 timeout;

if (timeout_s > WDT_MAX_TIMEOUT || timeout_s < WDT_MIN_TIMEOUT) - timeout = priv->timeout; + timeout_s = priv->timeout;

+ timeout = WDT_SEC2TICKS(timeout_s); /* Check if disabled */ if (readl(priv->regs + AT91_WDT_MR) & AT91_WDT_MR_WDDIS) { printf("sorry, watchdog is disabled\n");

With this 2 patches, same value as before commit 1473f6ac882fd is written into AT91_WDT_MR now ... but board reset thorugh WDT still remains ...

Seems with DM_WDT support, wdt reset() gets not called ...

Any ideas where to look at ?

And is it really necessary to call wdt_start() from board code to start wdt ? DTS entries for wdt seem correct to me.

Thanks!

bye, Heiko