[PATCH 09/13] drm/amd/display: Workaround IGT multiplane restriction

[Harry Wentland]

From: "Leo (Sunpeng) Li" <sunpeng.li at amd.com>

IGT currently does not properly commit changes on planes with multiple
possible CRTC's. Set one valid CRTC for each plane for now, plus one
underlay plane on Carizzo and Stoney that is valid for all CRTCs.

Change-Id: Ifcc37754a6e93e6fd9693d028354fa678c3a5d72
Signed-off-by: Leo (Sunpeng) Li <sunpeng.li at amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland at amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 14 +++++++++++++-
 1 file changed, 13 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 3bdf683e3e81..605da366ae10 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1189,6 +1189,7 @@ int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev)
 	struct amdgpu_encoder *aencoder = NULL;
 	struct amdgpu_mode_info *mode_info = &adev->mode_info;
 	uint32_t link_cnt;
+	unsigned long possible_crtcs;
 
 	link_cnt = dm->dc->caps.max_links;
 	if (amdgpu_dm_mode_config_init(dm->adev)) {
@@ -1204,7 +1205,18 @@ int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev)
 			goto fail_free_planes;
 		}
 		mode_info->planes[i]->base.type = mode_info->plane_type[i];
-		if (amdgpu_dm_plane_init(dm, mode_info->planes[i], 0xff)) {
+
+		/*
+		 * HACK: IGT tests expect that each plane can only have one
+		 * one possible CRTC. For now, set one CRTC for each
+		 * plane that is not an underlay, but still allow multiple
+		 * CRTCs for underlay planes.
+		 */
+		possible_crtcs = 1 << i;
+		if (i >= dm->dc->caps.max_streams)
+			possible_crtcs = 0xff;
+
+		if (amdgpu_dm_plane_init(dm, mode_info->planes[i], possible_crtcs)) {
 			DRM_ERROR("KMS: Failed to initialize plane\n");
 			goto fail_free_planes;
 		}
-- 
2.11.0