For now, there's just the one link config selection, optimizing for slow and wide link. No functional changes. Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 81 +++++++++++++++++++++++++---------------- 1 file changed, 50 insertions(+), 31 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 3c5fbdf42b9b..c98626b3af65 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1704,6 +1704,42 @@ static bool intel_edp_compare_alt_mode(struct drm_display_mode *m1, return bres; } +/* Optimize link config in order: max bpp, min clock, min lanes */ +static bool +intel_dp_compute_link_config_wide(struct intel_dp *intel_dp, + struct intel_crtc_state *pipe_config, + const struct link_config_limits *limits) +{ + struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode; + int bpp, clock, lane_count; + int mode_rate, link_clock, link_avail; + + for (bpp = limits->max_bpp; bpp >= limits->min_bpp; bpp -= 2 * 3) { + mode_rate = intel_dp_link_required(adjusted_mode->crtc_clock, + bpp); + + for (clock = limits->min_clock; clock <= limits->max_clock; clock++) { + for (lane_count = limits->min_lane_count; + lane_count <= limits->max_lane_count; + lane_count <<= 1) { + link_clock = intel_dp->common_rates[clock]; + link_avail = intel_dp_max_data_rate(link_clock, + lane_count); + + if (mode_rate <= link_avail) { + pipe_config->lane_count = lane_count; + pipe_config->pipe_bpp = bpp; + pipe_config->port_clock = link_clock; + + return true; + } + } + } + } + + return false; +} + static bool intel_dp_compute_link_config(struct intel_encoder *encoder, struct intel_crtc_state *pipe_config) @@ -1711,8 +1747,6 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode; struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base); struct link_config_limits limits; - int bpp, clock, lane_count; - int mode_rate, link_avail, link_clock; int common_len; common_len = intel_dp_common_len_rate_limit(intel_dp, @@ -1766,37 +1800,22 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, intel_dp->common_rates[limits.max_clock], limits.max_bpp, adjusted_mode->crtc_clock); - for (bpp = limits.max_bpp; bpp >= limits.min_bpp; bpp -= 2 * 3) { - mode_rate = intel_dp_link_required(adjusted_mode->crtc_clock, - bpp); - - for (clock = limits.min_clock; clock <= limits.max_clock; clock++) { - for (lane_count = limits.min_lane_count; - lane_count <= limits.max_lane_count; - lane_count <<= 1) { - - link_clock = intel_dp->common_rates[clock]; - link_avail = intel_dp_max_data_rate(link_clock, - lane_count); - - if (mode_rate <= link_avail) { - goto found; - } - } - } - } - - return false; - -found: - pipe_config->lane_count = lane_count; - pipe_config->pipe_bpp = bpp; - pipe_config->port_clock = intel_dp->common_rates[clock]; + /* + * Optimize for slow and wide. This is the place to add alternative + * optimization policy. + */ + if (!intel_dp_compute_link_config_wide(intel_dp, pipe_config, &limits)) + return false; DRM_DEBUG_KMS("DP lane count %d clock %d bpp %d\n", - pipe_config->lane_count, pipe_config->port_clock, bpp); - DRM_DEBUG_KMS("DP link bw required %i available %i\n", - mode_rate, link_avail); + pipe_config->lane_count, pipe_config->port_clock, + pipe_config->pipe_bpp); + + DRM_DEBUG_KMS("DP link rate required %i available %i\n", + intel_dp_link_required(adjusted_mode->crtc_clock, + pipe_config->pipe_bpp), + intel_dp_max_data_rate(pipe_config->port_clock, + pipe_config->lane_count)); return true; } -- 2.11.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx