lkml.org 
[lkml]   [2025]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v3 0/6] Add support to retrieve the bootstatus from watchdog for RZ/V2H(P) SoC
From
On 1/14/25 12:03, Rob Herring wrote:
> On Mon, Jan 13, 2025 at 11:38:08AM +0000, Biju Das wrote:
>> Hi Prabhakar,
>>
>>> -----Original Message-----
>>> From: Prabhakar <prabhakar.csengg@gmail.com>
>>> Sent: 13 January 2025 11:24
>>> Subject: [PATCH v3 0/6] Add support to retrieve the bootstatus from watchdog for RZ/V2H(P) SoC
>>>
>>> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>>>
>>> Hi All,
>>>
>>> This patch series adds SYSCON support to retrieve boot status information for RZ/V2H(P) SoC.
>>> Summary of Changes,
>>>
>>> Clock:
>>> Add syscon compatible support to the CPG block in bindings and
>>> device trees.
>>>
>>> Watchdog:
>>> Document the renesas,r9a09g057-syscon-wdt-errorrst property.
>>> Update the watchdog driver to fetch and report boot status via
>>> Error Reset Registers (CPG_ERROR_RSTm).
>>>
>>> Device Tree:
>>> Add the syscon property to CPG and WDT nodes in R9A09G057 and
>>> R9A09G047 SoC DTSI.
>>>
>>> These changes enable the watchdog driver to identify boot sources like Power-on Reset and Watchdog
>>> Reset, improving system diagnostics.
>>
>> This means that, we should assume U-boot/bootloader should not clear the WDT reset status bit.
>>
>> If they clear it, there should be a way to propagate it from u-boot/bootloader to linux,
>> otherwise, we get wrong bootstatus in linux.
>> But the clearing of watchdog status by one of the cases:
>>
>> 1) u-boot identify the boot source and clear the status bit
>> 2) u-boot identify the boot source and does not clear the status bit, but linux clear it.
>> 3) u-boot does not touch WDT status bits, but linux clear it.
>
> Sounds like the same problem as this[1]. If that works for you, please
> comment there. Always better if there is more than 1 user for something
> "common".
>
> Rob
>
> [1]https://lore.kernel.org/devicetree-spec/48defa98-9718-4997-86cb-b171187708a6@cherry.de/T/#u

If this ends up being provided through /chosen, it should probably be supported
in the watchdog core.

Guenter


\
 
 \ /
  Last update: 2025-01-14 21:17    [from the cache]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and my Meterkast|Read the blog