From: Nicholas Kazlauskas Date: Tue, 11 Jun 2019 16:54:05 +0000 (-0500) Subject: drm/amd/display: Don't set mode_changed=false if the stream was removed X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=7e93094945016492f6cb3660b2960d4b027eab51;p=openwrt%2Fstaging%2Fblogic.git drm/amd/display: Don't set mode_changed=false if the stream was removed [Why] When switching from vt to desktop with EDID emulation we can receive an atomic commit such that we have a crtc where mode_changed = true. During the dm_update_crtc_state disable pass we remove the stream from the context and free it on the dm_new_crtc_state. During the enable pass we compare the new provisional stream to the dm_old_crtc_state->stream and determine that the stream is unchanged and no scaling has been changed. Following this, new_crtc_state->mode_changed is then set to false. The connectors haven't changed and the CRTC active state hasn't changed so drm_atomic_crtc_needs_modeset returns false, so we jump to skip_modeset and we hit: BUG_ON(dm_new_crtc_state->stream == NULL); ...since the old stream is gone from the context and the new stream is also still NULL. [How] Ensure that we still a stream to reuse before checking if we can reuse the old stream without a full modeset. Signed-off-by: Nicholas Kazlauskas Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher --- 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 86308d7b5b3f..d8947fe5117c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -6344,7 +6344,17 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm, if (ret) goto fail; - if (dc_is_stream_unchanged(new_stream, dm_old_crtc_state->stream) && + /* + * If we already removed the old stream from the context + * (and set the new stream to NULL) then we can't reuse + * the old stream even if the stream and scaling are unchanged. + * We'll hit the BUG_ON and black screen. + * + * TODO: Refactor this function to allow this check to work + * in all conditions. + */ + if (dm_new_crtc_state->stream && + dc_is_stream_unchanged(new_stream, dm_old_crtc_state->stream) && dc_is_stream_scaling_unchanged(new_stream, dm_old_crtc_state->stream)) { new_crtc_state->mode_changed = false; DRM_DEBUG_DRIVER("Mode change not required, setting mode_changed to %d",