Currently, when bandwidth is insufficient for a given mode, we attempt to use DSC. This is indicated by a debug print, followed by a check for DSC support. The debug message states that we are trying DSC, but DSC might not be supported, which can give an incorrect picture in the logs if we bail out later. Correct the order for both DP and DP MST to: - Check if DSC is required and supported, and return early if DSC is not supported. - Print a debug message to indicate that DSC will be tried next. Suggested-by: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_dp.c | 8 +++++--- drivers/gpu/drm/i915/display/intel_dp_mst.c | 7 +++++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 0d74adae2ec9..4fa0e0b675b0 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -2642,15 +2642,17 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, dsc_needed = true; } + if (dsc_needed && !intel_dp_supports_dsc(intel_dp, connector, pipe_config)) { + drm_dbg_kms(display->drm, "DSC required but not available\n"); + return -EINVAL; + } + if (dsc_needed) { drm_dbg_kms(display->drm, "Try DSC (fallback=%s, joiner=%s, force=%s)\n", str_yes_no(ret), str_yes_no(joiner_needs_dsc), str_yes_no(intel_dp->force_dsc_en)); - if (!intel_dp_supports_dsc(intel_dp, connector, pipe_config)) - return -EINVAL; - if (!intel_dp_compute_config_limits(intel_dp, pipe_config, respect_downstream_limits, true, diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c index fffd199999e0..0433f2ff77e1 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c @@ -633,14 +633,17 @@ static int mst_stream_compute_config(struct intel_encoder *encoder, dsc_needed = true; } + if (dsc_needed && !intel_dp_supports_dsc(intel_dp, connector, pipe_config)) { + drm_dbg_kms(display->drm, "DSC required but not available\n"); + return -EINVAL; + } + /* enable compression if the mode doesn't fit available BW */ if (dsc_needed) { drm_dbg_kms(display->drm, "Try DSC (fallback=%s, joiner=%s, force=%s)\n", str_yes_no(ret), str_yes_no(joiner_needs_dsc), str_yes_no(intel_dp->force_dsc_en)); - if (!intel_dp_supports_dsc(intel_dp, connector, pipe_config)) - return -EINVAL; if (!mst_stream_compute_config_limits(intel_dp, connector, pipe_config, true, -- 2.45.2