This is a note to let you know that I've just added the patch titled
drm/amd/display: Properly handle additional cases where DCN is not supported
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amd-display-properly-handle-additional-cases-whe.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6e57ee2652ffb28b7ec0181a76e868bb27a0a84a
Author: Alex Deucher <alexander.deucher@xxxxxxx>
Date: Wed Jan 25 14:35:16 2023 -0500
drm/amd/display: Properly handle additional cases where DCN is not supported
[ Upstream commit 6fc547a5a2ef5ce05b16924106663ab92f8f87a7 ]
There could be boards with DCN listed in IP discovery, but no
display hardware actually wired up. In this case the vbios
display table will not be populated. Detect this case and
skip loading DM when we detect it.
v2: Mark DCN as harvested as well so other display checks
elsewhere in the driver are handled properly.
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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 e9797439bb0eb..3f325e1e440c9 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4428,6 +4428,17 @@ DEVICE_ATTR_WO(s3_debug);
static int dm_early_init(void *handle)
{
struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+ struct amdgpu_mode_info *mode_info = &adev->mode_info;
+ struct atom_context *ctx = mode_info->atom_context;
+ int index = GetIndexIntoMasterTable(DATA, Object_Header);
+ u16 data_offset;
+
+ /* if there is no object header, skip DM */
+ if (!amdgpu_atom_parse_data_header(ctx, index, NULL, NULL, NULL, &data_offset)) {
+ adev->harvest_ip_mask |= AMD_HARVEST_IP_DMU_MASK;
+ dev_info(adev->dev, "No object header, skipping DM\n");
+ return -ENOENT;
+ }
switch (adev->asic_type) {
#if defined(CONFIG_DRM_AMD_DC_SI)
