Re: [PATCH v2 0/4] drm/edid: Parse AMD VSDB FreeSync range in common code

Mario Limonciello <[email protected]> Fri, 24 Jul 2026 11:31:11 -0500
Newsgroups org.freedesktop.lists.amd-gfx,org.freedesktop.lists.dri-devel,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On 7/24/26 11:17, Alex Huang wrote:
> This patch series implements parsing for AMD VSDB block's FreeSync
> related data directly in the EDID common parser.
> 
> Some monitor manufacturers advertise their VRR capability exclusively
> using the AMD VSDB block's FreeSync data fields, many other
> manufacturers (notably pre EDID 1.4 monitors and some post 1.4 monitors)
> also do not include the relevant continuous frequency feature flag in
> the EDID. This makes it difficult to differentiate true VRR capability
> from supporting a few refresh rates between the range specified in EDID
> refresh rate range field in a spec compliant manner.
> 
> Incidentally also resolves a recent regression where amdgpu failed to
> detect some DP monitors as VRR capable after EDID parser was moved to
> DRM common.
> 
> v2:
> - Use a ladder style parser as suggested by Mario.
> - Validate payload lengths before parsing.
> - Removed an extra amd_vsdb_version reassignment.
> 
> Alex Huang (4):
>    drm/edid: Parse AMD VSDB for FreeSync refresh range
>    drm/amd/display: Use HDMI FreeSync range from common EDID parser
>    drm/amd/display: Clean up FreeSync capability detection
>    drm/amd/display: Remove unused DMCU/DMUB EDID CEA parser
> 
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 252 +++---------------
>   drivers/gpu/drm/amd/display/dc/Makefile       |   1 -
>   .../gpu/drm/amd/display/dc/dc_edid_parser.c   |  80 ------
>   .../gpu/drm/amd/display/dc/dc_edid_parser.h   |  44 ---
>   drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c | 121 ---------
>   drivers/gpu/drm/amd/display/dc/inc/hw/dmcu.h  |  10 -
>   .../gpu/drm/amd/display/dmub/inc/dmub_cmd.h   |  71 -----
>   drivers/gpu/drm/drm_edid.c                    | 141 ++++++++--
>   include/drm/drm_connector.h                   |  22 +-
>   9 files changed, 175 insertions(+), 567 deletions(-)
>   delete mode 100644 drivers/gpu/drm/amd/display/dc/dc_edid_parser.c
>   delete mode 100644 drivers/gpu/drm/amd/display/dc/dc_edid_parser.h
> 
> --
> 2.34.1
> 
Reviewed-by: Mario Limonciello (AMD) <[email protected]>