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 quic_sbillaka@quicinc.com Reviewed-by: Stephen Boyd swboyd@chromium.org --- 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 a40e798..c724cb0 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);