A DSC sink supporting DSC slice count N, not necessarily supports slice counts less than N. Hence the driver should check the sink's support for a particular slice count before using that slice count, fix intel_dp_dsc_get_slice_count() accordingly.
Cc: [email protected] Signed-off-by: Imre Deak <[email protected]> --- drivers/gpu/drm/i915/display/intel_dp.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 0ec82fcbcf48e..6d232c15a0b5a 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -1013,6 +1013,8 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector, int num_joined_pipes) { struct intel_display *display = to_intel_display(connector); + u32 sink_slice_count_mask = + drm_dp_dsc_sink_slice_count_mask(connector->dp.dsc_dpcd, false); u8 min_slice_count, i; int max_slice_width; int tp_rgb_yuv444; @@ -1084,9 +1086,9 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector, (!HAS_DSC_3ENGINES(display) || num_joined_pipes != 4)) continue; - if (test_slice_count > - drm_dp_dsc_sink_max_slice_count(connector->dp.dsc_dpcd, false)) - break; + if (!(drm_dp_dsc_slice_count_to_mask(test_slice_count) & + sink_slice_count_mask)) + continue; /* * Bigjoiner needs small joiner to be enabled. @@ -1103,8 +1105,14 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector, return test_slice_count; } - drm_dbg_kms(display->drm, "Unsupported Slice Count %d\n", - min_slice_count); + /* Print slice count 1,2,4,..24 if bit#0,1,3,..23 is set in the mask. */ + sink_slice_count_mask <<= 1; + drm_dbg_kms(display->drm, + "[CONNECTOR:%d:%s] Unsupported slice count (min: %d, sink supported: %*pbl)\n", + connector->base.base.id, connector->base.name, + min_slice_count, + (int)BITS_PER_TYPE(sink_slice_count_mask), &sink_slice_count_mask); + return 0; } -- 2.49.1
