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| author | Vladimir Stempen <vladimir.stempen@amd.com> | 2020-04-28 13:04:35 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2020-05-21 12:48:43 -0400 |
| commit | 7d1ee78f033a1b478cfa78eb4e11dd40e060f977 (patch) | |
| tree | 01a9d3dc98e37aa1380d431e679008bccfb5145f /drivers/gpu | |
| parent | c38606ab1250aad05829e0daa8fa9a002161eb2a (diff) | |
| download | linux-stable-7d1ee78f033a1b478cfa78eb4e11dd40e060f977.tar.gz linux-stable-7d1ee78f033a1b478cfa78eb4e11dd40e060f977.tar.bz2 linux-stable-7d1ee78f033a1b478cfa78eb4e11dd40e060f977.zip | |
drm/amd/display: DP training to set properly SCRAMBLING_DISABLE
[Why]
DP training sequence to set SCRAMBLING_DISABLE bit properly based on
training pattern - per DP Spec.
[How]
Update dpcd_pattern.v1_4.SCRAMBLING_DISABLE with 1 for TPS1, TPS2, TPS3,
but not for TPS4.
Signed-off-by: Vladimir Stempen <vladimir.stempen@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 1db592372435..91cd884d6f25 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -219,6 +219,30 @@ static enum dpcd_training_patterns return dpcd_tr_pattern; } +static uint8_t dc_dp_initialize_scrambling_data_symbols( + struct dc_link *link, + enum dc_dp_training_pattern pattern) +{ + uint8_t disable_scrabled_data_symbols = 0; + + switch (pattern) { + case DP_TRAINING_PATTERN_SEQUENCE_1: + case DP_TRAINING_PATTERN_SEQUENCE_2: + case DP_TRAINING_PATTERN_SEQUENCE_3: + disable_scrabled_data_symbols = 1; + break; + case DP_TRAINING_PATTERN_SEQUENCE_4: + disable_scrabled_data_symbols = 0; + break; + default: + ASSERT(0); + DC_LOG_HW_LINK_TRAINING("%s: Invalid HW Training pattern: %d\n", + __func__, pattern); + break; + } + return disable_scrabled_data_symbols; +} + static inline bool is_repeater(struct dc_link *link, uint32_t offset) { return (!link->is_lttpr_mode_transparent && offset != 0); @@ -251,6 +275,9 @@ static void dpcd_set_lt_pattern_and_lane_settings( dpcd_pattern.v1_4.TRAINING_PATTERN_SET = dc_dp_training_pattern_to_dpcd_training_pattern(link, pattern); + dpcd_pattern.v1_4.SCRAMBLING_DISABLE = + dc_dp_initialize_scrambling_data_symbols(link, pattern); + dpcd_lt_buffer[DP_TRAINING_PATTERN_SET - DP_TRAINING_PATTERN_SET] = dpcd_pattern.raw; |