[PATCH] board: mediatek: disable watchdog on BananaPi R2

[Stefan Roese]

Added Heinrich to Cc.

On 10.01.21 19:44, Matthias Brugger wrote:
> On 09/01/2021 15:57, Stefan Roese wrote:
>> On 09.01.21 03:32, Matthias Brugger wrote:
>>> On 08/01/2021 08:39, Stefan Roese wrote:
>>>> On 07.01.21 16:36, matthias.bgg at kernel.org wrote:
>>>>> From: Matthias Brugger <mbrugger at suse.com>
>>>>>
>>>>> Watchdog timeout comes in before we are able to load the
>>>>> kernel and reset the watchdog. Disable the watchdog late in the boot
>>>>> process to be able to boot the board.
>>>>
>>>> Can't you change the WDT reset timeout instead to a higher value?
>>>>
>>>
>>> I tried that, but the HW has a max timeout of 15984 ms. Unfortunately that's not
>>> enough.
>>
>> Nearly 16 seconds is not enough to boot into Linux so that the Linux
>> watchdog daemon can take control?
>>
> 
> Exactly. I'm using a standard distro image. I think the main problem is, that it
> needs 14 seconds for the EFI stub to actually boot the kernel.

I've not much experience (yet) with the "EFI stub". But if it takes this
long, wouldn't it make sense that this stub also supports the WDT?

Thanks,
Stefan

> I've already the
> watchdog timer as build-in (which is not the best to do, taking into account
> that we don't want to bloat our distro kernel with random board specific drivers
> build-in. If we I had the watchdog driver as kernel module it would take forever
> to get that loaded.
> 
> You can find a serial log with timestamp from the moment U-Boot got loaded until
> the kernel actually boots here:
> https://paste.opensuse.org/98390849
> 
> Regards,
> Matthias
> 
>> Thanks,
>> Stefan
>>
>>> Regards,
>>> Matthias
>>>
>>>> Thanks,
>>>> Stefan
>>>>
>>>>> Signed-off-by: Matthias Brugger <mbrugger at suse.com>
>>>>>
>>>>> ---
>>>>>
>>>>>     board/mediatek/mt7623/mt7623_rfb.c | 8 ++++++++
>>>>>     configs/mt7623n_bpir2_defconfig    | 1 +
>>>>>     2 files changed, 9 insertions(+)
>>>>>
>>>>> diff --git a/board/mediatek/mt7623/mt7623_rfb.c
>>>>> b/board/mediatek/mt7623/mt7623_rfb.c
>>>>> index 984e75ccaf..22120be412 100644
>>>>> --- a/board/mediatek/mt7623/mt7623_rfb.c
>>>>> +++ b/board/mediatek/mt7623/mt7623_rfb.c
>>>>> @@ -5,6 +5,7 @@
>>>>>       #include <common.h>
>>>>>     #include <mmc.h>
>>>>> +#include <watchdog.h>
>>>>>       DECLARE_GLOBAL_DATA_PTR;
>>>>>     @@ -40,3 +41,10 @@ int mmc_get_env_dev(void)
>>>>>         return mmc_get_boot_dev();
>>>>>     }
>>>>>     #endif
>>>>> +
>>>>> +#ifdef CONFIG_BOARD_LATE_INIT
>>>>> +int board_late_init(void)
>>>>> +{
>>>>> +    wdt_stop(gd->watchdog_dev);
>>>>> +}
>>>>> +#endif
>>>>> diff --git a/configs/mt7623n_bpir2_defconfig b/configs/mt7623n_bpir2_defconfig
>>>>> index 9177c17dff..fe0b6259dd 100644
>>>>> --- a/configs/mt7623n_bpir2_defconfig
>>>>> +++ b/configs/mt7623n_bpir2_defconfig
>>>>> @@ -14,6 +14,7 @@ CONFIG_FIT_VERBOSE=y
>>>>>     CONFIG_BOOTDELAY=3
>>>>>     CONFIG_SYS_CONSOLE_IS_IN_ENV=y
>>>>>     CONFIG_DEFAULT_FDT_FILE="mt7623n-bananapi-bpi-r2.dtb"
>>>>> +CONFIG_BOARD_LATE_INIT=y
>>>>>     # CONFIG_DISPLAY_BOARDINFO is not set
>>>>>     CONFIG_SYS_PROMPT="U-Boot> "
>>>>>     CONFIG_CMD_BOOTMENU=y
>>>>>
>>>>
>>>>
>>>> Viele Grüße,
>>>> Stefan
>>>>
>>>
>>
>>
>> Viele Grüße,
>> Stefan
>>
> 


Viele Grüße,
Stefan

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