[PATCH] drm/amdkfd: make CRAT table missing message informational only

[Felix Kuehling]

Am 2022-02-21 um 17:45 schrieb Alex Deucher:
> On Fri, Feb 18, 2022 at 11:25 PM Paul Menzel <pmenzel at molgen.mpg.de> wrote:
>> Dear Alex,
>>
>>
>> Thank you for the patch.
>>
>> Am 18.02.22 um 21:42 schrieb Alex Deucher:
>>> The driver has a fallback, to make the message informational
>> s/to/so/?
> fixed up locally.
>
>>> rather than a warning.
>> Maybe extend it a little?
> Done.
>
>> Component Resource Association Table (CRAT) are only applicable on some
>> AMD APUs. The message is perfectly expected. Even on AMD APUs we can now
>> fall back to treating it like a dGPU when the CRAT table is missing.
>>
>>> Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1906
>>> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
>>> ---
>>>    drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>>> index 24898238b024..1eaabd2cb41b 100644
>>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>>> @@ -1569,7 +1569,7 @@ int kfd_create_crat_image_acpi(void **crat_image, size_t *size)
>>>        /* Fetch the CRAT table from ACPI */
>>>        status = acpi_get_table(CRAT_SIGNATURE, 0, &crat_table);
>>>        if (status == AE_NOT_FOUND) {
>>> -             pr_warn("CRAT table not found\n");
>>> +             pr_info("CRAT table not found\n");
>> Maybe make it even a debug message, or only print it, when a
>> corresponding AMD APU is found like in `kfd_is_acpi_crat_invalid()`?
>> Especially since Linux logs
>>
>>           amdgpu: Virtual CRAT table created for CPU
>>
>>       later on.
>>
> I think it's still valid so you know that no CRAT table was found on
> the platform.  @Kuehling, Felix any opinion?

CRAT tables are only relevant on some generations of AMD APUs. Later 
developments of the ACPI standards have basically made it obsolete. Most 
systems today and in the future don't have a CRAT table. So I'm OK with 
not mentioning it when it's missing.

Regards,
   Felix


>
> Alex
>
>>>                return -ENODATA;
>>>        } else if (ACPI_FAILURE(status)) {
>>>                const char *err = acpi_format_exception(status);
>> Kind regards,
>>
>> Paul