6.13-stable review patch. If anyone has any objections, please let me know.
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From: Jani Nikula jani.nikula@intel.com
commit 230b19bc2bcc5897d0e20b4ce7e9790a469a2db0 upstream.
Commit 1c56e9a39833 ("drm/i915/dp: Get optimal link config to have best compressed bpp") tries to find the best compressed bpp for the link. However, it iterates from max to min bpp on display 13+, and from min to max on other platforms. This presumably leads to minimum compressed bpp always being chosen on display 11-12.
Iterate from high to low on all platforms to actually use the best possible compressed bpp.
Fixes: 1c56e9a39833 ("drm/i915/dp: Get optimal link config to have best compressed bpp") Cc: Ankit Nautiyal ankit.k.nautiyal@intel.com Cc: Imre Deak imre.deak@intel.com Cc: stable@vger.kernel.org # v6.7+ Reviewed-by: Imre Deak imre.deak@intel.com Reviewed-by: Ankit Nautiyal ankit.k.nautiyal@intel.com Signed-off-by: Jani Nikula jani.nikula@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/3bba67923cbcd13a59d26ef5fa4bb0... (cherry picked from commit 56b0337d429356c3b9ecc36a03023c8cc856b196) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_dp.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -2049,11 +2049,10 @@ icl_dsc_compute_link_config(struct intel /* Compressed BPP should be less than the Input DSC bpp */ dsc_max_bpp = min(dsc_max_bpp, pipe_bpp - 1);
- for (i = 0; i < ARRAY_SIZE(valid_dsc_bpp); i++) { - if (valid_dsc_bpp[i] < dsc_min_bpp) + for (i = ARRAY_SIZE(valid_dsc_bpp) - 1; i >= 0; i--) { + if (valid_dsc_bpp[i] < dsc_min_bpp || + valid_dsc_bpp[i] > dsc_max_bpp) continue; - if (valid_dsc_bpp[i] > dsc_max_bpp) - break;
ret = dsc_compute_link_config(intel_dp, pipe_config,