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| author | Arun R Murthy <arun.r.murthy@intel.com> | 2023-03-02 13:45:32 +0530 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2023-03-21 16:17:20 +0200 |
| commit | 1a324a40b452ae0a57676369c0a0150674728853 (patch) | |
| tree | b8120a8c3e4d55b25dc2334fbe124bbaa48f9aa1 /drivers/gpu/drm/i915/display/intel_dp_link_training.c | |
| parent | 562334d22a05a4793a620a9ef02516f3b8da9ec5 (diff) | |
| download | linux-1a324a40b452ae0a57676369c0a0150674728853.tar.gz linux-1a324a40b452ae0a57676369c0a0150674728853.tar.bz2 linux-1a324a40b452ae0a57676369c0a0150674728853.zip | |
i915/display/dp: SDP CRC16 for 128b132b link layer
Enable SDP error detection configuration, this will set CRC16 in
128b/132b link layer.
For Display version 13 a hardware bit31 in register VIDEO_DIP_CTL is
added to enable/disable SDP CRC applicable for DP2.0 only, but the
default value of this bit will enable CRC16 in 128b/132b hence
skipping this write.
Corrective actions on SDP corruption is yet to be defined.
v2: Moved the CRC enable to link training init(Jani N)
v3: Moved crc enable to ddi pre enable <Jani N>
v4: Separate function for SDP CRC16 (Jani N)
Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230302081532.765821-3-arun.r.murthy@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp_link_training.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_link_training.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c index bc5215eb84b1..d638054c74ac 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -1474,3 +1474,23 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp, if (!passed) intel_dp_schedule_fallback_link_training(intel_dp, crtc_state); } + +void intel_dp_128b132b_sdp_crc16(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state) +{ + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + + /* + * VIDEO_DIP_CTL register bit 31 should be set to '0' to not + * disable SDP CRC. This is applicable for Display version 13. + * Default value of bit 31 is '0' hence discarding the write + * TODO: Corrective actions on SDP corruption yet to be defined + */ + if (intel_dp_is_uhbr(crtc_state)) + /* DP v2.0 SCR on SDP CRC16 for 128b/132b Link Layer */ + drm_dp_dpcd_writeb(&intel_dp->aux, + DP_SDP_ERROR_DETECTION_CONFIGURATION, + DP_SDP_CRC16_128B132B_EN); + + drm_dbg_kms(&i915->drm, "DP2.0 SDP CRC16 for 128b/132b enabled\n"); +} |