From: Imre Deak Date: Wed, 15 Oct 2025 16:19:32 +0000 (+0300) Subject: drm/i915/dp_mst: Track DSC enabled status on the MST link X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7c027070e98d7b515e4d3a94b54d288c61cb5918;p=thirdparty%2Fkernel%2Flinux.git drm/i915/dp_mst: Track DSC enabled status on the MST link Track whether DSC is enabled on any CRTC on a link. On DP-SST (and DSI) this will always match the CRTC's DSC state, those links having only a single stream (aka CRTC). For instance, on DP-MST if DSC is enabled for CRTC#0, but disabled for CRTC#1, the DSC/FEC state for these CRTCs will be as follows: CRTC#0: - compression_enable = true - compression_enabled_on_link = true - fec_enable = true for 8b10b, false for 128b132b CRTC#1: - compression_enable = false - compression_enabled_on_link = true - fec_enable = true for 8b10b, false for 128b132b This patch only sets compression_enabled_on_link for CRTC#0 above and enables FEC on CRTC#0 if DSC was enabled on any other CRTC on the 8b10b MST link. A follow-up change will make sure that the state of all the CRTCs (CRTC#1 above) on an MST link is recomputed if DSC gets enabled on any CRTC, setting compression_enabled_on_link and fec_enable for these. Signed-off-by: Imre Deak Reviewed-by: Jouni Högander Link: https://lore.kernel.org/r/20251015161934.262108-6-imre.deak@intel.com --- diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 203dd38a9ec46..20747fa4d3daf 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -1279,6 +1279,8 @@ struct intel_crtc_state { /* Display Stream compression state */ struct { + /* Only used for state computation, not read out from the HW. */ + bool compression_enabled_on_link; bool compression_enable; int num_streams; /* Compressed Bpp in U6.4 format (first 4 bits for fractional part) */ diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 8441187359983..95884af242b3f 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -2387,7 +2387,7 @@ bool intel_dp_needs_8b10b_fec(const struct intel_crtc_state *crtc_state, if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_EDP)) return false; - return dsc_enabled_on_crtc; + return dsc_enabled_on_crtc || intel_dsc_enabled_on_link(crtc_state); } int intel_dp_dsc_compute_config(struct intel_dp *intel_dp, diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c index 803f3b395c79b..dbf2cf1b896da 100644 --- a/drivers/gpu/drm/i915/display/intel_vdsc.c +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c @@ -374,9 +374,20 @@ int intel_dsc_compute_params(struct intel_crtc_state *pipe_config) void intel_dsc_enable_on_crtc(struct intel_crtc_state *crtc_state) { + crtc_state->dsc.compression_enabled_on_link = true; crtc_state->dsc.compression_enable = true; } +bool intel_dsc_enabled_on_link(const struct intel_crtc_state *crtc_state) +{ + struct intel_display *display = to_intel_display(crtc_state); + + drm_WARN_ON(display->drm, crtc_state->dsc.compression_enable && + !crtc_state->dsc.compression_enabled_on_link); + + return crtc_state->dsc.compression_enabled_on_link; +} + enum intel_display_power_domain intel_dsc_power_domain(struct intel_crtc *crtc, enum transcoder cpu_transcoder) { diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.h b/drivers/gpu/drm/i915/display/intel_vdsc.h index 8c7c7fb652c31..99f64ac54b273 100644 --- a/drivers/gpu/drm/i915/display/intel_vdsc.h +++ b/drivers/gpu/drm/i915/display/intel_vdsc.h @@ -21,6 +21,7 @@ void intel_dsc_enable(const struct intel_crtc_state *crtc_state); void intel_dsc_disable(const struct intel_crtc_state *crtc_state); int intel_dsc_compute_params(struct intel_crtc_state *pipe_config); void intel_dsc_enable_on_crtc(struct intel_crtc_state *crtc_state); +bool intel_dsc_enabled_on_link(const struct intel_crtc_state *crtc_state); void intel_dsc_get_config(struct intel_crtc_state *crtc_state); enum intel_display_power_domain intel_dsc_power_domain(struct intel_crtc *crtc, enum transcoder cpu_transcoder);