diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 3ccdf765c1f0c999d56fd67b50fb02ee5ca9447a..b295dd32e076e854d6fd75dfd1a546c3a2e95600 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1689,6 +1689,231 @@ static bool intel_dp_dsc_supports_format(struct intel_dp *intel_dp,
return drm_dp_dsc_sink_supports_format(intel_dp->dsc_dpcd, sink_dsc_format);
}
+static bool is_bw_sufficient_for_dsc_config(u16 compressed_bpp, u32 link_clock,
+ u32 lane_count, u32 mode_clock,
+ enum intel_output_format output_format,
+ int timeslots)
+{
+ u32 available_bw, required_bw;
+
+ available_bw = (link_clock * lane_count * timeslots) / 8;
+ required_bw = compressed_bpp * (intel_dp_mode_to_fec_clock(mode_clock));
+
+ return available_bw > required_bw;
+}
+
+static int dsc_compute_link_config(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ struct link_config_limits *limits,
+ u16 compressed_bpp,
+ int timeslots)
+{
+ const struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
+ int link_rate, lane_count;
+ int i;
+
+ for (i = 0; i < intel_dp->num_common_rates; i++) {
+ link_rate = intel_dp_common_rate(intel_dp, i);
+ if (link_rate < limits->min_rate || link_rate > limits->max_rate)
+ continue;
+
+ for (lane_count = limits->min_lane_count;
+ lane_count <= limits->max_lane_count;
+ lane_count <<= 1) {
+ if (!is_bw_sufficient_for_dsc_config(compressed_bpp, link_rate, lane_count,
+ adjusted_mode->clock,
+ pipe_config->output_format,
+ timeslots))
+ continue;
+
+ pipe_config->lane_count = lane_count;
+ pipe_config->port_clock = link_rate;
+
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static
+u16 intel_dp_dsc_max_sink_compressed_bppx16(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ int bpc)
+{
+ u16 max_bppx16 = drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd);
+
+ if (max_bppx16)
+ return max_bppx16;
+ /*
+ * If support not given in DPCD 67h, 68h use the Maximum Allowed bit rate
+ * values as given in spec Table 2-157 DP v2.0
+ */
+ switch (pipe_config->output_format) {
+ case INTEL_OUTPUT_FORMAT_RGB:
+ case INTEL_OUTPUT_FORMAT_YCBCR444:
+ return (3 * bpc) << 4;
+ case INTEL_OUTPUT_FORMAT_YCBCR420:
+ return (3 * (bpc / 2)) << 4;
+ default:
+ MISSING_CASE(pipe_config->output_format);
+ break;
+ }
+
+ return 0;
+}
+
+static int 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) {
+ case INTEL_OUTPUT_FORMAT_RGB:
+ case INTEL_OUTPUT_FORMAT_YCBCR444:
+ return 8;
+ case INTEL_OUTPUT_FORMAT_YCBCR420:
+ return 6;
+ default:
+ MISSING_CASE(pipe_config->output_format);
+ break;
+ }
+
+ return 0;
+}
+
+static int dsc_sink_max_compressed_bpp(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ int bpc)
+{
+ return intel_dp_dsc_max_sink_compressed_bppx16(intel_dp,
+ pipe_config, bpc) >> 4;
+}
+
+static int dsc_src_min_compressed_bpp(void)
+{
+ /* Min Compressed bpp supported by source is 8 */
+ return 8;
+}
+
+static int dsc_src_max_compressed_bpp(struct intel_dp *intel_dp)
+{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+
+ /*
+ * Max Compressed bpp for Gen 13+ is 27bpp.
+ * For earlier platform is 23bpp. (Bspec:49259).
+ */
+ if (DISPLAY_VER(i915) <= 12)
+ return 23;
+ else
+ return 27;
+}
+
+/*
+ * From a list of valid compressed bpps try different compressed bpp and find a
+ * suitable link configuration that can support it.
+ */
+static int
+icl_dsc_compute_link_config(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ struct link_config_limits *limits,
+ int dsc_max_bpp,
+ int dsc_min_bpp,
+ int pipe_bpp,
+ int timeslots)
+{
+ int i, ret;
+
+ /* 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 ||
+ valid_dsc_bpp[i] > dsc_max_bpp)
+ break;
+
+ ret = dsc_compute_link_config(intel_dp,
+ pipe_config,
+ limits,
+ valid_dsc_bpp[i],
+ timeslots);
+ if (ret == 0) {
+ pipe_config->dsc.compressed_bpp = valid_dsc_bpp[i];
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+/*
+ * From XE_LPD onwards we supports compression bpps in steps of 1 up to
+ * uncompressed bpp-1. So we start from max compressed bpp and see if any
+ * link configuration is able to support that compressed bpp, if not we
+ * step down and check for lower compressed bpp.
+ */
+static int
+xelpd_dsc_compute_link_config(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ struct link_config_limits *limits,
+ int dsc_max_bpp,
+ int dsc_min_bpp,
+ int pipe_bpp,
+ int timeslots)
+{
+ u16 compressed_bpp;
+ int ret;
+
+ /* Compressed BPP should be less than the Input DSC bpp */
+ dsc_max_bpp = min(dsc_max_bpp, pipe_bpp - 1);
+
+ for (compressed_bpp = dsc_max_bpp;
+ compressed_bpp >= dsc_min_bpp;
+ compressed_bpp--) {
+ ret = dsc_compute_link_config(intel_dp,
+ pipe_config,
+ limits,
+ compressed_bpp,
+ timeslots);
+ if (ret == 0) {
+ pipe_config->dsc.compressed_bpp = compressed_bpp;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+static int dsc_compute_compressed_bpp(struct intel_dp *intel_dp,
+ struct intel_crtc_state *pipe_config,
+ struct link_config_limits *limits,
+ int pipe_bpp,
+ int timeslots)
+{
+ const struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+ int dsc_src_min_bpp, dsc_sink_min_bpp, dsc_min_bpp;
+ int dsc_src_max_bpp, dsc_sink_max_bpp, dsc_max_bpp;
+ 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_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
+
+ dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
+ dsc_sink_max_bpp = dsc_sink_max_compressed_bpp(intel_dp, 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,
+ adjusted_mode->hdisplay,
+ pipe_config->bigjoiner_pipes);
+ dsc_max_bpp = min(dsc_max_bpp, dsc_joiner_max_bpp);
+
+ if (DISPLAY_VER(i915) >= 13)
+ return xelpd_dsc_compute_link_config(intel_dp, pipe_config, limits,
+ dsc_max_bpp, dsc_min_bpp, pipe_bpp, timeslots);
+ return icl_dsc_compute_link_config(intel_dp, pipe_config, limits,
+ dsc_max_bpp, dsc_min_bpp, pipe_bpp, timeslots);
+}
+
static
u8 intel_dp_dsc_min_src_input_bpc(struct drm_i915_private *i915)
{
@@ -1744,52 +1969,55 @@ static int intel_dp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
struct link_config_limits *limits,
int timeslots)
{
- const struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
struct drm_i915_private *i915 = dp_to_i915(intel_dp);
- u16 output_bpp, dsc_max_compressed_bpp = 0;
+ u8 max_req_bpc = conn_state->max_requested_bpc;
+ u8 dsc_max_bpc, dsc_max_bpp;
+ u8 dsc_min_bpc, dsc_min_bpp;
+ u8 dsc_bpc[3] = {0};
int forced_bpp, pipe_bpp;
+ int num_bpc, i, ret;
forced_bpp = intel_dp_force_dsc_pipe_bpp(intel_dp, conn_state, limits);
if (forced_bpp) {
- pipe_bpp = forced_bpp;
- } else {
- pipe_bpp = intel_dp_dsc_compute_max_bpp(intel_dp, conn_state->max_requested_bpc);
-
- if (!is_dsc_pipe_bpp_sufficient(i915, conn_state, limits, pipe_bpp)) {
- drm_dbg_kms(&i915->drm,
- "Computed BPC is not in DSC BPC limits\n");
- return -EINVAL;
+ ret = dsc_compute_compressed_bpp(intel_dp, pipe_config,
+ limits, forced_bpp, timeslots);
+ if (ret == 0) {
+ pipe_config->pipe_bpp = forced_bpp;
+ return 0;
}
}
- /*
- * For now enable DSC for max link rate, max lane count.
- * Optimize this later for the minimum possible link rate/lane count
- * with DSC enabled for the requested mode.
- */
- pipe_config->port_clock = limits->max_rate;
- pipe_config->lane_count = limits->max_lane_count;
- dsc_max_compressed_bpp = intel_dp_dsc_get_max_compressed_bpp(i915,
- pipe_config->port_clock,
- pipe_config->lane_count,
- adjusted_mode->crtc_clock,
- adjusted_mode->crtc_hdisplay,
- pipe_config->bigjoiner_pipes,
- pipe_config->output_format,
- pipe_bpp,
- timeslots);
- if (!dsc_max_compressed_bpp) {
- drm_dbg_kms(&i915->drm, "Compressed BPP not supported\n");
+
+ dsc_max_bpc = intel_dp_dsc_min_src_input_bpc(i915);
+ if (!dsc_max_bpc)
return -EINVAL;
- }
- output_bpp = intel_dp_output_bpp(pipe_config->output_format, pipe_bpp);
+ dsc_max_bpc = min_t(u8, dsc_max_bpc, max_req_bpc);
+ dsc_max_bpp = min(dsc_max_bpc * 3, limits->max_bpp);
- pipe_config->dsc.compressed_bpp = min_t(u16, dsc_max_compressed_bpp, output_bpp);
+ dsc_min_bpc = intel_dp_dsc_min_src_input_bpc(i915);
+ dsc_min_bpp = max(dsc_min_bpc * 3, limits->min_bpp);
- pipe_config->pipe_bpp = pipe_bpp;
+ /*
+ * Get the maximum DSC bpc that will be supported by any valid
+ * link configuration and compressed bpp.
+ */
+ num_bpc = drm_dp_dsc_sink_supported_input_bpcs(intel_dp->dsc_dpcd, dsc_bpc);
+ for (i = 0; i < num_bpc; i++) {
+ pipe_bpp = dsc_bpc[i] * 3;
+ if (pipe_bpp < dsc_min_bpp)
+ break;
+ if (pipe_bpp > dsc_max_bpp)
+ continue;
+ ret = dsc_compute_compressed_bpp(intel_dp, pipe_config,
+ limits, pipe_bpp, timeslots);
+ if (ret == 0) {
+ pipe_config->pipe_bpp = pipe_bpp;
+ return 0;
+ }
+ }
- return 0;
+ return -EINVAL;
}
static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,