Re: [PATCH for 6.12 3/9] drm/amd/display: Disable fastboot on DCE 6 too

[Christian König]

On 3/30/26 16:21, Timur Kristóf wrote:
> On Monday, March 30, 2026 3:55:55 PM Central European Summer Time Christian 
> König wrote:
>> On 3/30/26 15:16, Timur Kristóf wrote:
>>> On Friday, March 27, 2026 12:47:10 AM Central European Summer Time Rosen
>>> Penev> 
>>> wrote:
>>>> From: Timur Kristóf <timur.kristof@xxxxxxxxx>
>>>>
>>>> [ Upstream commit 7495962cbceb967e095233a5673ea71f3bcdee7e ]
>>>>
>>>> It already didn't work on DCE 8,
>>>> so there is no reason to assume it would on DCE 6.
>>>>
>>>> Signed-off-by: Timur Kristóf <timur.kristof@xxxxxxxxx>
>>>> Reviewed-by: Rodrigo Siqueira <siqueira@xxxxxxxxxx>
>>>> Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
>>>> Reviewed-by: Alex Hung <alex.hung@xxxxxxx>
>>>> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
>>>> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
>>>
>>> This patch is incorrect and should not be backported.
>>>
>>> (Note that the error is already fixed upstream. For stable kernels IMO
>>> it's
>>> best to drop this one.)
>>
>> Is there some alternative which needs to be backported or should the old
>> kernel just work out of the box because we never enabled some feature
>> there?
>>
>> Apart from that the patch set looks good to me.
>>
> 
> This patch had a typo and does the opposite of what it should, ie. it disables 
> eDP fastboot on DCE10 and newer instead of disabling it on DCE8 and older.
> 
> The upstream fix is here:
> https://lists.freedesktop.org/archives/amd-gfx/2026-February/138577.html
> which disables eDP fastboot on DCE10 and older.

Thanks for the info.

@Rosen Penev can you either drop this patch here or send both this patch together with the fix for backporting?

With that done feel free to add Acked-by: Christian König <christian.koenig@xxxxxxx> to the series.

Thanks for taking care of this,
Christian.

> 
>>
>>>> ---
>>>>
>>>>  drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c | 6 ++----
>>>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
>>>> b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c index
>>>> df69e0cebf78..7dc99c85b8ea 100644
>>>> --- a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
>>>> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
>>>> @@ -1910,10 +1910,8 @@ void dce110_enable_accelerated_mode(struct dc *dc,
>>>> struct dc_state *context)
>>>>
>>>>  	get_edp_streams(context, edp_streams, &edp_stream_num);
>>>>
>>>> -	// Check fastboot support, disable on DCE8 because of blank
>>>
>>> screens
>>>
>>>> -	if (edp_num && edp_stream_num && dc->ctx->dce_version !=
>>>
>>> DCE_VERSION_8_0
>>>
>>>> && -		    dc->ctx->dce_version != DCE_VERSION_8_1 &&
>>>> -		    dc->ctx->dce_version != DCE_VERSION_8_3) {
>>>> +	/* Check fastboot support, disable on DCE 6-8 because of blank
>>>
>>> screens */
>>>
>>>> +	if (edp_num && edp_stream_num && dc->ctx->dce_version <
>>>
>>> DCE_VERSION_10_0)
>>>
>>>> { for (i = 0; i < edp_num; i++) {
>>>>
>>>>  			edp_link = edp_links[i];
>>>>  			if (edp_link != edp_streams[0]->link)
> 
> 
> 
>