Re: [PATCH v3 4/4] drm/amd/display: Remove unused DMCU/DMUB EDID CEA parser

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] FreeSync standard fallback range is skipped for monitors with an AMD VSDB that does not advertise FreeSync support.
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--- Patch [4]: [PATCH v3 4/4] drm/amd/display: Remove unused DMCU/DMUB EDID CEA parser ---
commit dc49dbde5bae751a6f9eaf5e370f73f95f12ba84
Author: Alex Huang <Alex.Huang2@amd.com>
Subject: drm/amd/display: Remove unused DMCU/DMUB EDID CEA parser

This commit removes the DMCU/DMUB EDID CEA parsing code, as HDMI FreeSync
detection is now handled by the common DRM EDID parser. All related fields
and files are deleted to avoid unnecessary firmware round-trips.

> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ ... @@ amdgpu_dm_update_freesync_caps()
>  		/* copy refresh rate info as long as VSDB advertises FreeSync */
>  		if (vsdb_info.freesync_supported) {
>  			amdgpu_dm_connector->min_vfreq = vsdb_info.min_refresh_rate_hz;
>  			amdgpu_dm_connector->max_vfreq = vsdb_info.max_refresh_rate_hz;
>  
>  			connector->display_info.monitor_range.min_vfreq =
>  				vsdb_info.min_refresh_rate_hz;
>  			connector->display_info.monitor_range.max_vfreq =
>  				vsdb_info.max_refresh_rate_hz;
>  		}

[Severity: Medium]
Will this leave amdgpu_dm_connector->min_vfreq and max_vfreq uninitialized
when a monitor has an AMD VSDB but doesn't advertise FreeSync support within
it?

By omitting an else branch for the freesync_supported == false condition,
it appears the fallback to connector->display_info.monitor_range is bypassed.

Could this silently disable FreeSync for monitors that otherwise support it
via standard DisplayID or base EDID VRR data, since the subsequent check
(max_vfreq - min_vfreq > 10) would then fail?

>  	} else {
>  		/* fall back to the base EDID range when there is no VSDB */
>  		amdgpu_dm_connector->min_vfreq = connector->display_info.monitor_range.min_vfreq;
>  		amdgpu_dm_connector->max_vfreq = connector->display_info.monitor_range.max_vfreq;
>  	}

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Sashiko AI review · https://sashiko.dev/#/patchset/20260804143339.714548-1-Alex.Huang2@amd.com?part=4