diff options
| author | Mario Limonciello <mario.limonciello@amd.com> | 2025-12-15 14:08:30 -0600 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2026-01-10 14:21:53 -0500 |
| commit | ac1e65d8ade46c09fb184579b81acadf36dcb91e (patch) | |
| tree | 4a07fe0eb8d0603ff586f084556610484707d5b0 | |
| parent | 99f77f6229c0766b980ae05affcf9f742d97de6a (diff) | |
drm/amd/display: Bump the HDMI clock to 340MHz
[Why]
DP-HDMI dongles can execeed bandwidth requirements on high resolution
monitors. This can lead to pruning the high resolution modes.
HDMI 1.3 bumped the clock to 340MHz, but display code never matched it.
[How]
Set default to (DVI) 165MHz. Once HDMI display is identified update
to 340MHz.
Reported-by: Dianne Skoll <dianne@skoll.ca>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4780
Reviewed-by: Chris Park <chris.park@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Matthew Stewart <matthew.stewart2@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/dc_hdmi_types.h | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/link_detection.c | 4 |
2 files changed, 4 insertions, 2 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/dc_hdmi_types.h b/drivers/gpu/drm/amd/display/dc/dc_hdmi_types.h index b015e80672ec..fcd3ab4b0045 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_hdmi_types.h +++ b/drivers/gpu/drm/amd/display/dc/dc_hdmi_types.h @@ -41,7 +41,7 @@ /* kHZ*/ #define DP_ADAPTOR_DVI_MAX_TMDS_CLK 165000 /* kHZ*/ -#define DP_ADAPTOR_HDMI_SAFE_MAX_TMDS_CLK 165000 +#define DP_ADAPTOR_HDMI_SAFE_MAX_TMDS_CLK 340000 struct dp_hdmi_dongle_signature_data { int8_t id[15];/* "DP-HDMI ADAPTOR"*/ diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c b/drivers/gpu/drm/amd/display/dc/link/link_detection.c index f24365395cd9..2c9d2b932482 100644 --- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c +++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c @@ -335,7 +335,7 @@ static void query_dp_dual_mode_adaptor( /* Assume we have no valid DP passive dongle connected */ *dongle = DISPLAY_DONGLE_NONE; - sink_cap->max_hdmi_pixel_clock = DP_ADAPTOR_HDMI_SAFE_MAX_TMDS_CLK; + sink_cap->max_hdmi_pixel_clock = DP_ADAPTOR_DVI_MAX_TMDS_CLK; /* Read DP-HDMI dongle I2c (no response interpreted as DP-DVI dongle)*/ if (!i2c_read( @@ -391,6 +391,8 @@ static void query_dp_dual_mode_adaptor( } } + if (is_valid_hdmi_signature) + sink_cap->max_hdmi_pixel_clock = DP_ADAPTOR_HDMI_SAFE_MAX_TMDS_CLK; if (is_type2_dongle) { uint32_t max_tmds_clk = |