Read out the branch devices' maximum overall DSC pixel throughput and line width and verify the mode's corresponding pixel clock and hactive period against these.
Signed-off-by: Imre Deak <[email protected]> --- .../drm/i915/display/intel_display_types.h | 8 +++ drivers/gpu/drm/i915/display/intel_dp.c | 62 +++++++++++++++++++ 2 files changed, 70 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 358ab922d7a76..73bdafae604f8 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -552,6 +552,14 @@ struct intel_connector { u8 dsc_hblank_expansion_quirk:1; u8 dsc_decompression_enabled:1; + + struct { + struct { + int rgb_yuv444; + int yuv422_420; + } overall_throughput; + int max_line_width; + } dsc_branch_caps; } dp; struct { diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 8cc123b0fd752..dd082d2fcc968 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -1042,6 +1042,20 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector, int tp_yuv422_420; u8 val; + /* + * TODO: Use the throughput value specific to the actual RGB/YUV + * format of the output. + * The RGB/YUV444 throughput value should be always either equal + * or smaller than the YUV422/420 value, but let's not depend on + * this assumption. + */ + if (mode_clock > max(connector->dp.dsc_branch_caps.overall_throughput.rgb_yuv444, + connector->dp.dsc_branch_caps.overall_throughput.yuv422_420)) + return 0; + + if (mode_hdisplay > connector->dp.dsc_branch_caps.max_line_width) + return 0; + val = connector->dp.dsc_dpcd[DP_DSC_PEAK_THROUGHPUT - DP_DSC_SUPPORT]; tp_rgb_yuv444 = dsc_per_slice_throughput(display, mode_clock, REG_FIELD_GET8(DP_DSC_THROUGHPUT_MODE_0_MASK, @@ -4204,6 +4218,44 @@ static void intel_dp_read_dsc_dpcd(struct drm_dp_aux *aux, dsc_dpcd); } +static int dsc_branch_overall_throughput(u8 bw_code) +{ + switch (bw_code) { + case 0: + return INT_MAX; + case 1: + return 680000; + default: + return 600000 + 50000 * bw_code; + } +} + +static void init_dsc_overall_throughput_limits(struct intel_connector *connector, bool is_branch) +{ + u8 branch_caps[3]; + + connector->dp.dsc_branch_caps.overall_throughput.rgb_yuv444 = INT_MAX; + connector->dp.dsc_branch_caps.overall_throughput.yuv422_420 = INT_MAX; + connector->dp.dsc_branch_caps.max_line_width = INT_MAX; + + if (!is_branch) + return; + + if (drm_dp_dpcd_read_data(connector->dp.dsc_decompression_aux, + DP_DSC_BRANCH_OVERALL_THROUGHPUT_0, branch_caps, + sizeof(branch_caps)) != 0) + return; + + connector->dp.dsc_branch_caps.overall_throughput.rgb_yuv444 = + dsc_branch_overall_throughput(branch_caps[0]); + + connector->dp.dsc_branch_caps.overall_throughput.yuv422_420 = + dsc_branch_overall_throughput(branch_caps[1]); + + if (branch_caps[2] != 0) + connector->dp.dsc_branch_caps.max_line_width = branch_caps[2] * 320; +} + void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, const struct drm_dp_desc *desc, bool is_branch, struct intel_connector *connector) @@ -4219,6 +4271,8 @@ void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, /* Clear fec_capable to avoid using stale values */ connector->dp.fec_capability = 0; + memset(&connector->dp.dsc_branch_caps, 0, sizeof(connector->dp.dsc_branch_caps)); + if (dpcd_rev < DP_DPCD_REV_14) return; @@ -4233,6 +4287,11 @@ void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, drm_dbg_kms(display->drm, "FEC CAPABILITY: %x\n", connector->dp.fec_capability); + + if (!(connector->dp.dsc_dpcd[0] & DP_DSC_DECOMPRESSION_IS_SUPPORTED)) + return; + + init_dsc_overall_throughput_limits(connector, is_branch); } static void intel_edp_get_dsc_sink_cap(u8 edp_dpcd_rev, struct intel_connector *connector) @@ -4241,6 +4300,9 @@ static void intel_edp_get_dsc_sink_cap(u8 edp_dpcd_rev, struct intel_connector * return; intel_dp_read_dsc_dpcd(connector->dp.dsc_decompression_aux, connector->dp.dsc_dpcd); + + if (connector->dp.dsc_dpcd[0] & DP_DSC_DECOMPRESSION_IS_SUPPORTED) + init_dsc_overall_throughput_limits(connector, false); } static void -- 2.49.1
