On 2018-04-19 03:43 AM, Michel Dänzer wrote:
>
> [ Dropping stable@ (fixes with Cc: stable are picked up for stable
> branches once they land in Linus' tree, there's no point sending them to
> stable@ during review), adding dri-devel ]
>
> On 2018-04-18 10:26 PM, Harry Wentland wrote:
>> The below commit
>>
>> "drm/atomic: Try to preserve the crtc enabled state in drm_atomic_remove_fb, v2"
>>
>> introduces a slight behavioral change to rmfb. Instead of disabling a crtc
>> when the primary plane is disabled, it now preserves it.
>>
>> Since DC is currently not equipped to handle this we need to fail such
>> a commit, otherwise we might see a corrupted screen.
>
> How does the caller react to failing such a commit?
The caller (drm_atomic_remove_fb in this case) will retry with the old behavior and disable the CRTC.
Harry
>
>
>> This is based on Shirish's previous approach but avoids adding all
>> planes to the new atomic state which leads to a full update in DC for
>> any commit, and is not what we intend.
>>
>> Theoretically DM should be able to deal with states with fully populated planes,
>> even for simple updates, such as cursor updates. This should still be
>> addressed in the future.
>>
>> Signed-off-by: Harry Wentland <harry.wentland at amd.com>
>> Cc: stable at vger.kernel.org
>> ---
>> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 10 +++++++++-
>> 1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> index 6f92a19bebd6..0bdc6b484bad 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
>> @@ -4683,6 +4683,7 @@ static int dm_update_crtcs_state(struct amdgpu_display_manager *dm,
>> struct amdgpu_dm_connector *aconnector = NULL;
>> struct drm_connector_state *new_con_state = NULL;
>> struct dm_connector_state *dm_conn_state = NULL;
>> + struct drm_plane_state *new_plane_state = NULL;
>>
>> new_stream = NULL;
>>
>> @@ -4690,6 +4691,13 @@ static int dm_update_crtcs_state(struct amdgpu_display_manager *dm,
>> dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
>> acrtc = to_amdgpu_crtc(crtc);
>>
>> + new_plane_state = drm_atomic_get_new_plane_state(state, new_crtc_state->crtc->primary);
>> +
>> + if (new_crtc_state->enable && new_plane_state && !new_plane_state->fb) {
>> + ret = -EINVAL;
>> + goto fail;
>> + }
>> +
>> aconnector = amdgpu_dm_find_first_crtc_matching_connector(state, crtc);
>>
>> /* TODO This hack should go away */
>> @@ -4894,7 +4902,7 @@ static int dm_update_planes_state(struct dc *dc,
>> if (!dm_old_crtc_state->stream)
>> continue;
>>
>> - DRM_DEBUG_DRIVER("Disabling DRM plane: %d on DRM crtc %d\n",
>> + DRM_DEBUG_ATOMIC("Disabling DRM plane: %d on DRM crtc %d\n",
>> plane->base.id, old_plane_crtc->base.id);
>>
>> if (!dc_remove_plane_from_context(
>>
>
>
