From: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
Currently we seem to be using wrong DPCD register for reading
compressed bpps, reading min/max input bpc instead of compressed bpp.
Fix that, so that we now apply min/max compressed bpp limitations we
get from DP Spec Table 2-157 DP v2.0 and/or correspondent DPCD
register DP_DSC_MAX_BITS_PER_PIXEL_LOW/HIGH.
This might also allow us to get rid of an ugly compressed bpp
recalculation, which we had to add to make some MST hubs usable.
v2: - Fix operator precedence
v3: - Added debug info about compressed bpps
v4: - Don't try to intersect Sink input bpp and compressed bpps.
v5: - Decrease step while looking for suitable compressed bpp to
accommodate.
v6: - Use helper for getting min and max compressed_bpp (Ankit)
v7: - Fix checkpatch warning (Ankit)
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_dp.c | 20 +++++---
drivers/gpu/drm/i915/display/intel_dp.h | 4 ++
drivers/gpu/drm/i915/display/intel_dp_mst.c | 54 ++++++++++-----------
3 files changed, 41 insertions(+), 37 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 969f19484c53c..c926478621753 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1811,7 +1811,7 @@ u16 intel_dp_dsc_max_sink_compressed_bppx16(const struct intel_connector *connec
return 0;
}
-static int dsc_sink_min_compressed_bpp(struct intel_crtc_state *pipe_config)
+int intel_dp_dsc_sink_min_compressed_bpp(struct intel_crtc_state *pipe_config)
{
/* From Mandatory bit rate range Support Table 2-157 (DP v2.0) */
switch (pipe_config->output_format) {
@@ -1828,9 +1828,9 @@ static int dsc_sink_min_compressed_bpp(struct intel_crtc_state *pipe_config)
return 0;
}
-static int dsc_sink_max_compressed_bpp(const struct intel_connector *connector,
- struct intel_crtc_state *pipe_config,
- int bpc)
+int intel_dp_dsc_sink_max_compressed_bpp(const struct intel_connector *connector,
+ struct intel_crtc_state *pipe_config,
+ int bpc)
{
return intel_dp_dsc_max_sink_compressed_bppx16(connector,
pipe_config, bpc) >> 4;
@@ -1944,12 +1944,14 @@ static int dsc_compute_compressed_bpp(struct intel_dp *intel_dp,
int dsc_joiner_max_bpp;
dsc_src_min_bpp = dsc_src_min_compressed_bpp();
- dsc_sink_min_bpp = dsc_sink_min_compressed_bpp(pipe_config);
+ dsc_sink_min_bpp = intel_dp_dsc_sink_min_compressed_bpp(pipe_config);
dsc_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
dsc_min_bpp = max(dsc_min_bpp, to_bpp_int_roundup(limits->link.min_bpp_x16));
dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
- dsc_sink_max_bpp = dsc_sink_max_compressed_bpp(connector, pipe_config, pipe_bpp / 3);
+ dsc_sink_max_bpp = intel_dp_dsc_sink_max_compressed_bpp(connector,
+ pipe_config,
+ pipe_bpp / 3);
dsc_max_bpp = dsc_sink_max_bpp ? min(dsc_sink_max_bpp, dsc_src_max_bpp) : dsc_src_max_bpp;
dsc_joiner_max_bpp = get_max_compressed_bpp_with_joiner(i915, adjusted_mode->clock,
@@ -2104,12 +2106,14 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
pipe_config->lane_count = limits->max_lane_count;
dsc_src_min_bpp = dsc_src_min_compressed_bpp();
- dsc_sink_min_bpp = dsc_sink_min_compressed_bpp(pipe_config);
+ dsc_sink_min_bpp = intel_dp_dsc_sink_min_compressed_bpp(pipe_config);
dsc_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
dsc_min_bpp = max(dsc_min_bpp, to_bpp_int_roundup(limits->link.min_bpp_x16));
dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
- dsc_sink_max_bpp = dsc_sink_max_compressed_bpp(connector, pipe_config, pipe_bpp / 3);
+ dsc_sink_max_bpp = intel_dp_dsc_sink_max_compressed_bpp(connector,
+ pipe_config,
+ pipe_bpp / 3);
dsc_max_bpp = dsc_sink_max_bpp ? min(dsc_sink_max_bpp, dsc_src_max_bpp) : dsc_src_max_bpp;
dsc_max_bpp = min(dsc_max_bpp, to_bpp_int(limits->link.max_bpp_x16));
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 75ffab92bba41..af535b3f03ae9 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -126,6 +126,10 @@ u16 intel_dp_dsc_get_max_compressed_bpp(struct drm_i915_private *i915,
enum intel_output_format output_format,
u32 pipe_bpp,
u32 timeslots);
+int intel_dp_dsc_sink_min_compressed_bpp(struct intel_crtc_state *pipe_config);
+int intel_dp_dsc_sink_max_compressed_bpp(const struct intel_connector *connector,
+ struct intel_crtc_state *pipe_config,
+ int bpc);
u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector,
int mode_clock, int mode_hdisplay,
bool bigjoiner);
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index d6c52906ac6c3..457ace825d931 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -157,6 +157,9 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder,
crtc_state->port_clock,
crtc_state->lane_count);
+ drm_dbg_kms(&i915->drm, "Looking for slots in range min bpp %d max bpp %d\n",
+ min_bpp, max_bpp);
+
for (bpp = max_bpp; bpp >= min_bpp; bpp -= step) {
struct intel_link_m_n remote_m_n;
int link_bpp;
@@ -246,8 +249,7 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
u8 dsc_bpc[3] = {};
int min_bpp, max_bpp, sink_min_bpp, sink_max_bpp;
u8 dsc_max_bpc;
- bool need_timeslot_recalc = false;
- u32 last_compressed_bpp;
+ int min_compressed_bpp, max_compressed_bpp;
/* Max DSC Input BPC for ICL is 10 and for TGL+ is 12 */
if (DISPLAY_VER(i915) >= 12)
@@ -283,38 +285,32 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
if (max_bpp > sink_max_bpp)
max_bpp = sink_max_bpp;
- min_bpp = max(min_bpp, to_bpp_int_roundup(limits->link.min_bpp_x16));
- max_bpp = min(max_bpp, to_bpp_int(limits->link.max_bpp_x16));
+ max_compressed_bpp = intel_dp_dsc_sink_max_compressed_bpp(connector,
+ crtc_state,
+ max_bpp / 3);
+ max_compressed_bpp = min(max_compressed_bpp,
+ to_bpp_int(limits->link.max_bpp_x16));
- slots = intel_dp_mst_find_vcpi_slots_for_bpp(encoder, crtc_state, max_bpp,
- min_bpp, limits,
- conn_state, 2 * 3, true);
+ min_compressed_bpp = intel_dp_dsc_sink_min_compressed_bpp(crtc_state);
+ min_compressed_bpp = max(min_compressed_bpp,
+ to_bpp_int_roundup(limits->link.min_bpp_x16));
+
+ drm_dbg_kms(&i915->drm, "DSC Sink supported compressed min bpp %d compressed max bpp %d\n",
+ min_compressed_bpp, max_compressed_bpp);
+
+ /* Align compressed bpps according to our own constraints */
+ max_compressed_bpp = intel_dp_dsc_nearest_valid_bpp(i915, max_compressed_bpp,
+ crtc_state->pipe_bpp);
+ min_compressed_bpp = intel_dp_dsc_nearest_valid_bpp(i915, min_compressed_bpp,
+ crtc_state->pipe_bpp);
+
+ slots = intel_dp_mst_find_vcpi_slots_for_bpp(encoder, crtc_state, max_compressed_bpp,
+ min_compressed_bpp, limits,
+ conn_state, 1, true);
if (slots < 0)
return slots;
- last_compressed_bpp = crtc_state->dsc.compressed_bpp;
-
- crtc_state->dsc.compressed_bpp = intel_dp_dsc_nearest_valid_bpp(i915,
- last_compressed_bpp,
- crtc_state->pipe_bpp);
-
- if (crtc_state->dsc.compressed_bpp != last_compressed_bpp)
- need_timeslot_recalc = true;
-
- /*
- * Apparently some MST hubs dislike if vcpi slots are not matching precisely
- * the actual compressed bpp we use.
- */
- if (need_timeslot_recalc) {
- slots = intel_dp_mst_find_vcpi_slots_for_bpp(encoder, crtc_state,
- crtc_state->dsc.compressed_bpp,
- crtc_state->dsc.compressed_bpp,
- limits, conn_state, 2 * 3, true);
- if (slots < 0)
- return slots;
- }
-
return 0;
}
static int intel_dp_mst_update_slots(struct intel_encoder *encoder,
