From 162f807858d15bde60cf373a3ad46e03200ad9d8 Mon Sep 17 00:00:00 2001 From: Martin Leung Date: Wed, 13 Feb 2019 17:06:31 -0500 Subject: [PATCH] drm/amd/display: half bandwidth for YCbCr420 during validation [Why] used to be unable to run 4:2:0 if using a dongle because 4k60 bandwidth exceeded dongle caps [How] half pixel clock during comparison to dongle cap. *Could get stuck on black screen on monitor that don't support 420 but will be selecting 420 as preferred mode* Signed-off-by: Martin Leung Reviewed-by: Wenjing Liu Acked-by: Aidan Wood Acked-by: Bhawanpreet Lakha Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 33 ++++++++++++++++----------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 4f4fa3791b5d..93826f0a0aaa 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -2074,11 +2074,28 @@ static void disable_link(struct dc_link *link, enum signal_type signal) } } +static uint32_t get_timing_pixel_clock_100hz(const struct dc_crtc_timing *timing) +{ + + uint32_t pxl_clk = timing->pix_clk_100hz; + + if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420) + pxl_clk /= 2; + else if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR422) + pxl_clk = pxl_clk * 2 / 3; + + if (timing->display_color_depth == COLOR_DEPTH_101010) + pxl_clk = pxl_clk * 10 / 8; + else if (timing->display_color_depth == COLOR_DEPTH_121212) + pxl_clk = pxl_clk * 12 / 8; + + return pxl_clk; +} + static bool dp_active_dongle_validate_timing( const struct dc_crtc_timing *timing, const struct dpcd_caps *dpcd_caps) { - unsigned int required_pix_clk_100hz = timing->pix_clk_100hz; const struct dc_dongle_caps *dongle_caps = &dpcd_caps->dongle_caps; switch (dpcd_caps->dongle_type) { @@ -2115,13 +2132,6 @@ static bool dp_active_dongle_validate_timing( return false; } - - /* Check Color Depth and Pixel Clock */ - if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420) - required_pix_clk_100hz /= 2; - else if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR422) - required_pix_clk_100hz = required_pix_clk_100hz * 2 / 3; - switch (timing->display_color_depth) { case COLOR_DEPTH_666: case COLOR_DEPTH_888: @@ -2130,14 +2140,11 @@ static bool dp_active_dongle_validate_timing( case COLOR_DEPTH_101010: if (dongle_caps->dp_hdmi_max_bpc < 10) return false; - required_pix_clk_100hz = required_pix_clk_100hz * 10 / 8; break; case COLOR_DEPTH_121212: if (dongle_caps->dp_hdmi_max_bpc < 12) return false; - required_pix_clk_100hz = required_pix_clk_100hz * 12 / 8; break; - case COLOR_DEPTH_141414: case COLOR_DEPTH_161616: default: @@ -2145,7 +2152,7 @@ static bool dp_active_dongle_validate_timing( return false; } - if (required_pix_clk_100hz > (dongle_caps->dp_hdmi_max_pixel_clk * 10)) + if (get_timing_pixel_clock_100hz(timing) > (dongle_caps->dp_hdmi_max_pixel_clk * 10)) return false; return true; @@ -2166,7 +2173,7 @@ enum dc_status dc_link_validate_mode_timing( return DC_OK; /* Passive Dongle */ - if (0 != max_pix_clk && timing->pix_clk_100hz > max_pix_clk) + if (max_pix_clk != 0 && get_timing_pixel_clock_100hz(timing) > max_pix_clk) return DC_EXCEED_DONGLE_CAP; /* Active Dongle*/ -- 2.11.0