[PATCH 00/19] Fix Adaptive Sync SDP for PR with Link ON + Auxless ALPM

Ankit Nautiyal
2026-03-30T04:22:01Z

Enable Adaptive Sync SDP for Panel replay + auxless ALPM.
First few patches are fixes in existing AS SDP enablement.
Later patches add the support to send AS SDP for Panel replay with Link
ON and with auxless ALPM (Link-Off).

This series is in continuation from discussions in [1] [2] and more
recent [3]:

Apart from few patches from [3] new changes include:
- Some clean up in drm/dp Macros
- Add new DPCD bit to get FAVT PAYLOAD FIELDS PARSING SUPPORT.
- Add AS SDP version and PR and VRR specific bits in drm_dp.h.
- Modify AS SDP compute config to accomodate PR with Link On and Link
Off.
- Program Downspread Ctrl DPCD bits.
- Make way for T1 and T2 AS SDP transmission timing/position.

[1] https://lore.kernel.org/all/1b8c6c6de1e5fe0db83e6ae942dfee7e6f950767.camel@intel.com/
[2] https://lore.kernel.org/all/aPtqdAxDwiuQZbrn@intel.com/
[3] https://lore.kernel.org/intel-gfx/7c2d6f4e-69e6-452a-89cc-5fd4254430bd@intel.com/T/#m6e8beab2cc3b6ff9d61f740f107d83a2f4e08114

Rev2:
- Drop the redundant version member for AS SDP, and use the member
revision
- Drop member to store AS SDP transmission time, use simple helper
instead.
- Use Burst mode to write Panel Replay config DPCDs.
- Split AS SDP configuration in compute_config() and
compute_config_late() phase.
- Always enable AS SDP whenever supported by source + sink.

Rev3:
- Use ASYNC_VIDEO_TIMING_NOT_SUPPORTED_IN_PR bit also to determine AS
SDP v2 support.
- Drop patch to make provision to send AS SDP v1.
- Add patch to include all relevant AS SDP fields in comparison.
- Other refactor improvements suggested by Ville.

Ankit Nautiyal (19):
drm/dp: Rename and relocate AS SDP payload field masks
drm/dp: Clean up DPRX feature enumeration macros
drm/dp: Add bits for AS SDP FAVT Payload Fields Parsing support
drm/dp: Add DPCD for configuring AS SDP for PR + VRR
drm/i915/dp: Fix readback for target_rr in Adaptive Sync SDP
drm/i915/vrr: Avoid vrr for PCON with HDMI2.1 sink
drm/i915/dp: Account for AS_SDP guardband only when enabled
drm/i915/dp: Add a helper to decide if AS SDP can be used
drm/i915/dp: Skip AS SDP for DP branch devices
drm/i915/dp: Use revision field of AS SDP data structure
drm/i915/dp: Include all relevant AS SDP fields in comparison
drm/i915/dp: Add member to intel_dp to store AS SDP v2 support
drm/i915/psr: Write the PR config DPCDs in burst mode
drm/i915/display: Add helper for AS SDP transmission time selection
drm/i915/psr: Program Panel Replay CONFIG3 using AS SDP transmission
time
drm/i915/dp: Set relevant Downspread Ctrl DPCD bits for PR + Auxless
ALPM
drm/i915/dp: Program AS SDP DB[1:0] for PR with Link off
drm/i915/dp: Split AS SDP computation between compute_config and
compute_config_late
drm/i915/dp: Always enable AS SDP if supported by source + sink

drivers/gpu/drm/i915/display/intel_alpm.c | 20 ++-
drivers/gpu/drm/i915/display/intel_display.c | 6 +-
.../drm/i915/display/intel_display_types.h | 1 +
drivers/gpu/drm/i915/display/intel_dp.c | 147 ++++++++++++++----
drivers/gpu/drm/i915/display/intel_dp.h | 2 +
.../drm/i915/display/intel_dp_link_training.c | 10 +-
.../drm/i915/display/intel_dp_link_training.h | 3 +-
drivers/gpu/drm/i915/display/intel_dp_mst.c | 2 +-
drivers/gpu/drm/i915/display/intel_psr.c | 30 ++--
drivers/gpu/drm/i915/display/intel_vrr.c | 10 ++
include/drm/display/drm_dp.h | 19 ++-
11 files changed, 194 insertions(+), 56 deletions(-)

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2.45.2