[U-Boot] [PATCH] dfu: cmd: trigger watchdog before calling usb_gadget_handle_interrupts

[Heiko Schocher <hs@denx.de>]

Hello Lukasz,

Am 17.03.2015 13:56, schrieb Lukasz Majewski:
> Hi Heiko,
>
>> Hello Lukasz,
>>
>> Am 17.03.2015 10:52, schrieb Lukasz Majewski:
>>> Hi Heiko,
>>>
>>>> trigger watchdog before calling usb_gadget_handle_interrupts()
>>>> This prevents board resets when calling dfu command on boards
>>>> which have a watchdog.
>>>>
>>>> Signed-off-by: Heiko Schocher <hs@denx.de>
>>>> ---
>>>>
>>>>    common/cmd_dfu.c | 2 ++
>>>>    1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/common/cmd_dfu.c b/common/cmd_dfu.c
>>>> index e975abe..46af4cf 100644
>>>> --- a/common/cmd_dfu.c
>>>> +++ b/common/cmd_dfu.c
>>>> @@ -9,6 +9,7 @@
>>>>     */
>>>>
>>>>    #include <common.h>
>>>> +#include <watchdog.h>
>>>>    #include <dfu.h>
>>>>    #include <g_dnl.h>
>>>>    #include <usb.h>
>>>> @@ -64,6 +65,7 @@ static int do_dfu(cmd_tbl_t *cmdtp, int flag, int
>>>> argc, char * const argv[]) if (ctrlc())
>>>>    			goto exit;
>>>>
>>>> +		WATCHDOG_RESET();
>>>>    		usb_gadget_handle_interrupts();
>>>>    	}
>>>>    exit:
>>>
>>> It seems strange for me, that we must reset watchdog when looping in
>>> the dfu.
>>
>> Hmm.. maybe I overlook something, but If you look into this while(1)
>> loop, there is no trigger of the watchdog ... and if I start the dfu
>> command without a USB cable on the board, what triggers the boards
>> watchdog?
>
> So the problem is when cable is not attached to the board and you call
> dfu command to execute?

Yes.

>>> What is the WATCHDOG interval on the affected board?
>>
>> ~5 seconds
>>
>> Ah, this is on an at91 board .. and in the
>> drivers/serial/atmel_usart.c atmel_serial_tstc() is no
>> WATCHDOG_RESET...
>>
>> So ctrlc() does not trigger the watchdog
>
> Could you be a bit more specific here. Does your board expect ctrlc()
> to update watchdog, so it won't reset?

I do not know, if ctrlc() must trigger the WDT ... I just looked into
the while(1) loop in common/cmd_dfu.c. There is only ctrlc() which
could trigger the WDT... and on at91 it does not trigger it ...

If dfu transfer is started there is some output on the console, which
triggers the WDT too ... do you have a board with a running WDT?

bye,
Heiko
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