Intel-XE Archive on lore.kernel.org
 help / color / mirror / Atom feed
* [v3 0/4] drm/i915/display: Enable AS SDP Skip Frames
@ 2026-08-31 12:59 Uma Shankar
  2026-08-31 12:59 ` [v3 1/4] drm/i915/display: Enable periodic AS SDP skip frames Uma Shankar
                   ` (7 more replies)
  0 siblings, 8 replies; 13+ messages in thread
From: Uma Shankar @ 2026-08-31 12:59 UTC (permalink / raw)
  To: intel-gfx, intel-xe; +Cc: dibin.moolakadan.subrahmanian, Uma Shankar

When Panel Replay is active the transcoder timing generator runs at the
panel's maximum refresh rate, but content is often presented at a lower
rate. In that case the Adaptive-Sync SDP (AS SDP) only needs to reach the
panel often enough to satisfy its maximum frame time, so transmitting it
on every frame is redundant and shows up as repeated SDPs on the link.

Xe3LPD adds a HW skip-frame counter in PR_ALPM_CTL that lets the source
send a single AS SDP and then suppress it for a programmed number of
frames. Program this counter so that one AS SDP is followed by
(max_vrefresh / flip_rate - 1) idle frames, matching the effective
content rate and allowing the link to be driven down to as low as 1Hz
when the hardware supports it.

v3:
 - Add module parameter
 - Fix Skip count clearing issue (Dibin)
 - Add DC3Co checks and enabling conditions
 
Uma Shankar (4):
  drm/i915/display: Enable periodic AS SDP skip frames
  drm/i915/display: Force disable DC3co when AS SDP skip frames is
    enabled
  drm/i915/display: Reprogram AS SDP skip frames on seamless VRR
    transitions
  drm/i915/display: Gate periodic AS SDP skip frames behind a module
    parameter

 drivers/gpu/drm/i915/display/intel_alpm.c     | 158 ++++++++++++++++--
 drivers/gpu/drm/i915/display/intel_alpm.h     |   3 +
 drivers/gpu/drm/i915/display/intel_display.c  |  19 ++-
 .../drm/i915/display/intel_display_params.c   |   6 +
 .../drm/i915/display/intel_display_params.h   |   1 +
 .../drm/i915/display/intel_display_power.c    |   9 +
 drivers/gpu/drm/i915/display/intel_psr_regs.h |   2 +
 7 files changed, 181 insertions(+), 17 deletions(-)

-- 
2.50.1


^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2026-08-31 20:20 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-08-31 12:59 [v3 0/4] drm/i915/display: Enable AS SDP Skip Frames Uma Shankar
2026-08-31 12:59 ` [v3 1/4] drm/i915/display: Enable periodic AS SDP skip frames Uma Shankar
2026-08-31 12:52   ` sashiko-bot
2026-08-31 12:59 ` [v3 2/4] drm/i915/display: Force disable DC3co when AS SDP skip frames is enabled Uma Shankar
2026-08-31 12:57   ` sashiko-bot
2026-08-31 12:59 ` [v3 3/4] drm/i915/display: Reprogram AS SDP skip frames on seamless VRR transitions Uma Shankar
2026-08-31 12:53   ` sashiko-bot
2026-08-31 12:59 ` [v3 4/4] drm/i915/display: Gate periodic AS SDP skip frames behind a module parameter Uma Shankar
2026-08-31 12:52   ` sashiko-bot
2026-08-31 16:05 ` ✗ CI.checkpatch: warning for drm/i915/display: Enable AS SDP Skip Frames (rev4) Patchwork
2026-08-31 16:06 ` ✓ CI.KUnit: success " Patchwork
2026-08-31 17:16 ` ✓ Xe.CI.BAT: " Patchwork
2026-08-31 20:20 ` ✓ Xe.CI.FULL: " Patchwork

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox