diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2023-10-24 04:08:57 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-01-26 02:35:31 +0300 |
| commit | 4e042f022255604c68ab5d5f73c8f437d24d651e (patch) | |
| tree | fce05adc1ae3e245adcd15eaafb9de3ef421a351 /include/drm | |
| parent | 16af1e7f5ea64160fa831118d3ae73b4ba1c2452 (diff) | |
| download | linux-4e042f022255604c68ab5d5f73c8f437d24d651e.tar.xz | |
drm/dp_mst: Fix fractional DSC bpp handling
[ Upstream commit 7707dd6022593f3edd8e182e7935870cf326f874 ]
The current code does '(bpp << 4) / 16' in the MST PBN
calculation, but that is just the same as 'bpp' so the
DSC codepath achieves absolutely nothing. Fix it up so that
the fractional part of the bpp value is actually used instead
of truncated away. 64*1006 has enough zero lsbs that we can
just shift that down in the dividend and thus still manage
to stick to a 32bit divisor.
And while touching this, let's just make the whole thing more
straightforward by making the passed in bpp value .4 binary
fixed point always, instead of having to pass in different
things based on whether DSC is enabled or not.
v2:
- Fix DSC kunit test cases.
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: David Francis <David.Francis@amd.com>
Cc: Mikita Lipski <mikita.lipski@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Fixes: dc48529fb14e ("drm/dp_mst: Add PBN calculation for DSC modes")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[Imre: Fix kunit test cases]
Acked-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231030155843.2251023-3-imre.deak@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include/drm')
| -rw-r--r-- | include/drm/display/drm_dp_mst_helper.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/drm/display/drm_dp_mst_helper.h b/include/drm/display/drm_dp_mst_helper.h index ed5c9660563c..8eeb6730ac6d 100644 --- a/include/drm/display/drm_dp_mst_helper.h +++ b/include/drm/display/drm_dp_mst_helper.h @@ -832,7 +832,7 @@ struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, int drm_dp_get_vc_payload_bw(const struct drm_dp_mst_topology_mgr *mgr, int link_rate, int link_lane_count); -int drm_dp_calc_pbn_mode(int clock, int bpp, bool dsc); +int drm_dp_calc_pbn_mode(int clock, int bpp); void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap); |