[PATCH 3/3] drm/amdgpu: add vce bypass mode for tonga.

[Andy Furniss]

Andy Furniss wrote:
> This regresses vce perf badly on tonga
>
> https://bugs.freedesktop.org/show_bug.cgi?id=97494
>
> Maybe I need a better test case or faster cpu or something,
> but vce powerplay encode issues disappeared for me with the latest
> firmware.

I did eventually find an issue - but I don't know if it's what the
comment below referred to.

vaapi cbr since the mesa commit that enabled dual instance
can sometimes produce different md5sums, though the vid is visually
OK. Maybe gstreamer timing based as it can be reduced by changing
cpufreq from on_demand to perf or adding ! queue !. Higher bitrates
seem to not have the issue, cqp doesn't seem affected.

>
> root wrote:
>> From: Rex Zhu <Rex.Zhu at amd.com>
>>
>> fix issue that encode test failed on the second time when
>> vce dpm enabled on tonga.
>>
>> Signed-off-by: Rex Zhu <Rex.Zhu at amd.com>
>>
>> Change-Id: I9c77b631b977ab5cc14dc553b6e6beb502e4bd0e
>> Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/vce_v3_0.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
>> b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
>> index df66abe..168b0db 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
>> @@ -704,7 +704,8 @@ static int vce_v3_0_set_clockgating_state(void
>> *handle,
>>       bool enable = (state == AMD_CG_STATE_GATE) ? true : false;
>>       int i;
>>
>> -    if (adev->asic_type == CHIP_POLARIS10)
>> +    if ((adev->asic_type == CHIP_POLARIS10) ||
>> +        (adev->asic_type == CHIP_TONGA))
>>           vce_v3_0_set_bypass_mode(adev, enable);
>>
>>       if (!(adev->cg_flags & AMD_CG_SUPPORT_VCE_MGCG))
>>
>