Reduce link rate and re start link training if link training 1 failed due to loss of clock recovery done to fix Link Layer CTS case 4.3.1.7. Also only update voltage and pre-emphasis swing level after link training started to fix Link Layer CTS case 4.3.1.6. Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx> --- drivers/gpu/drm/msm/dp/dp_ctrl.c | 86 ++++++++++++++++++++++++++-------------- 1 file changed, 56 insertions(+), 30 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 27fb0f0..6f8443d 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -83,13 +83,6 @@ struct dp_ctrl_private { struct completion video_comp; }; -struct dp_cr_status { - u8 lane_0_1; - u8 lane_2_3; -}; - -#define DP_LANE0_1_CR_DONE 0x11 - static int dp_aux_link_configure(struct drm_dp_aux *aux, struct dp_link_info *link) { @@ -1080,7 +1073,7 @@ static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl, } static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl, - struct dp_cr_status *cr, int *training_step) + u8 *cr, int *training_step) { int tries, old_v_level, ret = 0; u8 link_status[DP_LINK_STATUS_SIZE]; @@ -1109,8 +1102,8 @@ static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl, if (ret) return ret; - cr->lane_0_1 = link_status[0]; - cr->lane_2_3 = link_status[1]; + cr[0] = link_status[0]; + cr[1] = link_status[1]; if (drm_dp_clock_recovery_ok(link_status, ctrl->link->link_params.num_lanes)) { @@ -1188,7 +1181,7 @@ static void dp_ctrl_clear_training_pattern(struct dp_ctrl_private *ctrl) } static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl, - struct dp_cr_status *cr, int *training_step) + u8 *cr, int *training_step) { int tries = 0, ret = 0; char pattern; @@ -1204,10 +1197,6 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl, else pattern = DP_TRAINING_PATTERN_2; - ret = dp_ctrl_update_vx_px(ctrl); - if (ret) - return ret; - ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, pattern); if (ret) return ret; @@ -1220,8 +1209,8 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl, ret = dp_ctrl_read_link_status(ctrl, link_status); if (ret) return ret; - cr->lane_0_1 = link_status[0]; - cr->lane_2_3 = link_status[1]; + cr[0] = link_status[0]; + cr[1] = link_status[1]; if (drm_dp_channel_eq_ok(link_status, ctrl->link->link_params.num_lanes)) { @@ -1241,7 +1230,7 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl, static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl); static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, - struct dp_cr_status *cr, int *training_step) + u8 *cr, int *training_step) { int ret = 0; u8 encoding = DP_SET_ANSI_8B10B; @@ -1282,7 +1271,7 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, } static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl, - struct dp_cr_status *cr, int *training_step) + u8 *cr, int *training_step) { int ret = 0; @@ -1496,14 +1485,14 @@ static int dp_ctrl_deinitialize_mainlink(struct dp_ctrl_private *ctrl) static int dp_ctrl_link_maintenance(struct dp_ctrl_private *ctrl) { int ret = 0; - struct dp_cr_status cr; + u8 cr_status[2]; int training_step = DP_TRAINING_NONE; dp_ctrl_push_idle(&ctrl->dp_ctrl); ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock; - ret = dp_ctrl_setup_main_link(ctrl, &cr, &training_step); + ret = dp_ctrl_setup_main_link(ctrl, cr_status, &training_step); if (ret) goto end; @@ -1634,6 +1623,41 @@ void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl) } } +static bool dp_ctrl_any_lane_cr_done(struct dp_ctrl_private *ctrl, + u8 *cr_status) + +{ + int i; + u8 status; + int lane = ctrl->link->link_params.num_lanes; + + for (i = 0; i < lane; i++) { + status = cr_status[i / 2]; + status >>= ((i % 2) * 4); + if (status & DP_LANE_CR_DONE) + return true; + } + + return false; +} + +static bool dp_ctrl_any_lane_cr_lose(struct dp_ctrl_private *ctrl, + u8 *cr_status) +{ + int i; + u8 status; + int lane = ctrl->link->link_params.num_lanes; + + for (i = 0; i < lane; i++) { + status = cr_status[i / 2]; + status >>= ((i % 2) * 4); + if (!(status & DP_LANE_CR_DONE)) + return true; + } + + return false; +} + int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) { int rc = 0; @@ -1641,7 +1665,7 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) u32 rate = 0; int link_train_max_retries = 5; u32 const phy_cts_pixel_clk_khz = 148500; - struct dp_cr_status cr; + u8 cr_status[2]; unsigned int training_step; if (!dp_ctrl) @@ -1681,19 +1705,18 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) } training_step = DP_TRAINING_NONE; - rc = dp_ctrl_setup_main_link(ctrl, &cr, &training_step); + rc = dp_ctrl_setup_main_link(ctrl, cr_status, &training_step); if (rc == 0) { /* training completed successfully */ break; } else if (training_step == DP_TRAINING_1) { /* link train_1 failed */ - if (!dp_catalog_link_is_connected(ctrl->catalog)) { + if (!dp_catalog_link_is_connected(ctrl->catalog)) break; - } rc = dp_ctrl_link_rate_down_shift(ctrl); if (rc < 0) { /* already in RBR = 1.6G */ - if (cr.lane_0_1 & DP_LANE0_1_CR_DONE) { + if (dp_ctrl_any_lane_cr_done(ctrl, cr_status)) { /* * some lanes are ready, * reduce lane number @@ -1709,12 +1732,15 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) } } } else if (training_step == DP_TRAINING_2) { - /* link train_2 failed, lower lane rate */ - if (!dp_catalog_link_is_connected(ctrl->catalog)) { + /* link train_2 failed */ + if (!dp_catalog_link_is_connected(ctrl->catalog)) break; - } - rc = dp_ctrl_link_lane_down_shift(ctrl); + if (dp_ctrl_any_lane_cr_lose(ctrl, cr_status)) + rc = dp_ctrl_link_rate_down_shift(ctrl); + else + rc = dp_ctrl_link_lane_down_shift(ctrl); + if (rc < 0) { /* end with failure */ break; /* lane == 1 already */ -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project