diff options
| author | Sankeerth Billakanti <quic_sbillaka@quicinc.com> | 2021-11-02 13:18:44 +0530 |
|---|---|---|
| committer | Rob Clark <robdclark@chromium.org> | 2021-11-28 09:32:03 -0800 |
| commit | 34f3b16575d1c371399ba8e2724d2bd67f75a0f5 (patch) | |
| tree | 1e1f902c5581f4eaed12c09e915ca0073e92684e /drivers/gpu/drm | |
| parent | 447a39f4e89d992f82f03521d46746f6a4348578 (diff) | |
| download | linux-34f3b16575d1c371399ba8e2724d2bd67f75a0f5.tar.bz2 | |
drm/msm/dp: Enable downspread for supported DP sinks
The sc7280 eDP sink that supports downspread will fail link training
if source does not enable SSC / downspread. This change will set the
downspread bit in the DP sink if supported and indicate SSC support
to the DP PHY driver.
Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1635839325-401-5-git-send-email-quic_sbillaka@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/msm/dp/dp_ctrl.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 62e75dc8afc6..a40e79871012 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1228,7 +1228,9 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, int *training_step) { int ret = 0; + const u8 *dpcd = ctrl->panel->dpcd; u8 encoding = DP_SET_ANSI_8B10B; + u8 ssc; struct dp_link_info link_info = {0}; dp_ctrl_config_ctrl(ctrl); @@ -1238,6 +1240,12 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, link_info.capabilities = DP_LINK_CAP_ENHANCED_FRAMING; dp_aux_link_configure(ctrl->aux, &link_info); + + if (drm_dp_max_downspread(dpcd)) { + ssc = DP_SPREAD_AMP_0_5; + drm_dp_dpcd_write(ctrl->aux, DP_DOWNSPREAD_CTRL, &ssc, 1); + } + drm_dp_dpcd_write(ctrl->aux, DP_MAIN_LINK_CHANNEL_CODING_SET, &encoding, 1); @@ -1312,9 +1320,11 @@ static int dp_ctrl_enable_mainlink_clocks(struct dp_ctrl_private *ctrl) struct dp_io *dp_io = &ctrl->parser->io; struct phy *phy = dp_io->phy; struct phy_configure_opts_dp *opts_dp = &dp_io->phy_opts.dp; + const u8 *dpcd = ctrl->panel->dpcd; opts_dp->lanes = ctrl->link->link_params.num_lanes; opts_dp->link_rate = ctrl->link->link_params.rate / 100; + opts_dp->ssc = drm_dp_max_downspread(dpcd); dp_ctrl_set_clock_rate(ctrl, DP_CTRL_PM, "ctrl_link", ctrl->link->link_params.rate * 1000); @@ -1406,7 +1416,7 @@ void dp_ctrl_host_deinit(struct dp_ctrl *dp_ctrl) static bool dp_ctrl_use_fixed_nvid(struct dp_ctrl_private *ctrl) { - u8 *dpcd = ctrl->panel->dpcd; + const u8 *dpcd = ctrl->panel->dpcd; /* * For better interop experience, used a fixed NVID=0x8000 |