Re: [PATCH 0/2] drm/amd/display: stabilize DCN35 ODM and DSC sequencing

[Mario Limonciello <mario.limonciello@amd.com>]

On 8/25/26 4:18 PM, Mauricio Bellon wrote:
> From: Mauricio Bellon <mbellon@lenovo.com>
> 
> Two related direct DisplayPort failures occur on DCN35 with a
> high-refresh DSC stream using two-way ODM. A normal transition from
> 4K120 to 4K144 can commit successfully but produce no visible output.
> After 4K144 is working, a long-pulse hotplug can reconstruct the same
> stream but leave the monitor black.
> 
> The first patch stabilizes the DCN35 ODM update. It exposes the missing
> ODM double-buffer pending-clear callback, keeps the horizontal timing
> divider under manual control while programming the ODM topology, waits
> for the update to complete, and restores the timing-derived target
> manual mode.
> 
> The second patch enables sink DSC before source DSC in the DPMS-on
> pre-enable path and removes the later redundant sink DSC enablement.
> 
> The complete series was built and booted as
> 7.1.0-bellon18-amd-final+ on a Lenovo ThinkPad X13 Gen 6 AMD with a
> Krackan Point Radeon 840M and Corsair Xeneon 32UHD144 connected directly
> through USB-C DP Alt Mode SST.
> 
> The following scenarios all produced stable visible output:
> 
> - 4K144 initial modeset
> - 4K120 to 4K144
> - 4K144 to 4K120 to 4K144
> - 4K144 long-pulse unplug/replug
> - repeated 4K144 unplug/replug cycles
> 
> This series covers the direct-SST modeset and hotplug reconstruction
> failures. It does not claim to address the separate DPIA/MST warning
> observed through the USB4 dock.
> 
> The commits retain my Lenovo author and Signed-off-by address. This
> submission is sent through my personal Gmail account because Lenovo
> email is not compatible with git send-email.
> 
> Bug report:
> https://gitlab.freedesktop.org/drm/amd/-/issues/5033

Thanks for the submission.  If there ends up being any changes to it, I 
would suggest adding to both the code commits:

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5033

No need to spin for now, whoever reviews and accepts this can add that 
when committing.

> 
> Mauricio Bellon (2):
>    drm/amd/display: stabilize DCN35 ODM update sequencing
>    drm/amd/display: enable sink DSC before source DSC
> 
>   .../amd/display/dc/hwss/dcn35/dcn35_hwseq.c   | 20 +++++++++++++++++--
>   .../gpu/drm/amd/display/dc/link/link_dpms.c   |  5 +++--
>   .../amd/display/dc/optc/dcn35/dcn35_optc.c    |  2 ++
>   3 files changed, 23 insertions(+), 4 deletions(-)
> 
> 
> base-commit: 232bf7d5453df6cc0d877a1003f9aa172e9750de