diff options
| author | Arun R Murthy <arun.r.murthy@intel.com> | 2025-07-30 16:03:20 +0530 |
|---|---|---|
| committer | Ankit Nautiyal <ankit.k.nautiyal@intel.com> | 2025-08-04 12:47:44 +0530 |
| commit | 904eef7dd0aecd71f7c3b264439275cb9cdab6af (patch) | |
| tree | 7f16dcde92fe7870da92d1969323edef5a7c281d /drivers/gpu/drm/i915/display/intel_dp.c | |
| parent | f8b99c61a8ac1dc94520fea7d5660ae09a047c9f (diff) | |
drm/i915/display: Use the recomended min_hblank values
Use recommended values as per wa_14021694213 to compare with the
calculated value and choose minimum of them.
v2: corrected checkpatch warning and retain the restriction for
min_hblank (Jani)
v3: use calculated value to compare with recomended value and choose
minimum of them (Imre)
v4: As driver supported min bpc is 8, omit the condition check for
bpc6 with ycbcr420. Added a note for the same (Imre)
v5: Add a warn for the unexpected case of 6bpc + uhbr + ycbcr420
v6: Reworded the comments and check fo anything < compressed bpp 8(Imre)
v7: Fix checkpatch warning. (Ankit)
Bspec: 74379
Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://lore.kernel.org/r/20250730-min_hblank-v7-1-179360220ced@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 54d88f24b689..625036c47bdf 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -3182,7 +3182,26 @@ int intel_dp_compute_min_hblank(struct intel_crtc_state *crtc_state, */ min_hblank = min_hblank - 2; - min_hblank = min(10, min_hblank); + /* + * min_hblank formula is undergoing a change, to avoid underrun use the + * recomended value in spec to compare with the calculated one and use the + * minimum value + */ + if (intel_dp_is_uhbr(crtc_state)) { + /* + * Note: Bspec requires a min_hblank of 2 for YCBCR420 + * with compressed bpp 6, but the minimum compressed bpp + * supported by the driver is 8. + */ + drm_WARN_ON(display->drm, + (crtc_state->dsc.compression_enable && + crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 && + crtc_state->dsc.compressed_bpp_x16 < fxp_q4_from_int(8))); + min_hblank = min(3, min_hblank); + } else { + min_hblank = min(10, min_hblank); + } + crtc_state->min_hblank = min_hblank; return 0; |