From 016aa55082c2dd16e438e18e23f8bd8a67f30d84 Mon Sep 17 00:00:00 2001 From: Sankeerth Billakanti Date: Tue, 2 Nov 2021 13:18:45 +0530 Subject: [PATCH] drm/msm/dp: Enable ASSR for supported DP sinks The eDP sink on sc7280 supports ASSR and dp driver will enable ASSR in the source hardware. The driver needs to enable the ASSR field in the DPCD configuration register to avoid screen corruption. This change will enable ASSR if supported in the sink device. Signed-off-by: Sankeerth Billakanti Reviewed-by: Stephen Boyd Link: https://lore.kernel.org/r/1635839325-401-6-git-send-email-quic_sbillaka@quicinc.com Signed-off-by: Dmitry Baryshkov Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/dp/dp_ctrl.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index a40e79871012f..c724cb0bde9dc 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -119,13 +119,13 @@ void dp_ctrl_push_idle(struct dp_ctrl *dp_ctrl) static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl) { u32 config = 0, tbd; - u8 *dpcd = ctrl->panel->dpcd; + const u8 *dpcd = ctrl->panel->dpcd; /* Default-> LSCLK DIV: 1/4 LCLK */ config |= (2 << DP_CONFIGURATION_CTRL_LSCLK_DIV_SHIFT); /* Scrambler reset enable */ - if (dpcd[DP_EDP_CONFIGURATION_CAP] & DP_ALTERNATE_SCRAMBLER_RESET_CAP) + if (drm_dp_alternate_scrambler_reset_cap(dpcd)) config |= DP_CONFIGURATION_CTRL_ASSR; tbd = dp_link_get_test_bits_depth(ctrl->link, @@ -1231,6 +1231,7 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, const u8 *dpcd = ctrl->panel->dpcd; u8 encoding = DP_SET_ANSI_8B10B; u8 ssc; + u8 assr; struct dp_link_info link_info = {0}; dp_ctrl_config_ctrl(ctrl); @@ -1249,6 +1250,12 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, drm_dp_dpcd_write(ctrl->aux, DP_MAIN_LINK_CHANNEL_CODING_SET, &encoding, 1); + if (drm_dp_alternate_scrambler_reset_cap(dpcd)) { + assr = DP_ALTERNATE_SCRAMBLER_RESET_ENABLE; + drm_dp_dpcd_write(ctrl->aux, DP_EDP_CONFIGURATION_SET, + &assr, 1); + } + ret = dp_ctrl_link_train_1(ctrl, training_step); if (ret) { DRM_ERROR("link training #1 failed. ret=%d\n", ret); -- 2.30.2