From patchwork Thu Aug 5 20:44:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuogee Hsieh X-Patchwork-Id: 12422069 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0F79C4338F for ; Thu, 5 Aug 2021 20:45:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8CEC161108 for ; Thu, 5 Aug 2021 20:45:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241178AbhHEUpw (ORCPT ); Thu, 5 Aug 2021 16:45:52 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:13469 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241151AbhHEUpv (ORCPT ); Thu, 5 Aug 2021 16:45:51 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1628196337; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=HEVRlvJUyoJTBxWhCCgclG5h4ZrOIhRln/nxYocThVE=; b=wdxbrsyDeeQYu+vAHT+AIP3gYoG/Jbo2X68uSucnnP1IkakClaNpDGYj8QCNtyA6bPmzOnvO uVaPTnV/IN2liUnBd9m+Ephp0Ra6q3HvgR0pzbhDmUOUDTOP5/7jX/OLQ66Xybix4GOJ4crU jRY51LhVv/UEfp9Q5l2+srTCMkE= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n03.prod.us-east-1.postgun.com with SMTP id 610c4df0ad1af639498450c3 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 05 Aug 2021 20:45:36 GMT Sender: khsieh=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id C8C14C4360C; Thu, 5 Aug 2021 20:45:35 +0000 (UTC) Received: from khsieh-linux1.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: khsieh) by smtp.codeaurora.org (Postfix) with ESMTPSA id A71B3C433D3; Thu, 5 Aug 2021 20:45:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org A71B3C433D3 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=khsieh@codeaurora.org From: Kuogee Hsieh To: dri-devel@lists.freedesktop.org, robdclark@gmail.com, sean@poorly.run, swboyd@chromium.org Cc: Kuogee Hsieh , abhinavk@codeaurora.org, aravindh@codeaurora.org, airlied@linux.ie, daniel@ffwll.ch, bjorn.andersson@linaro.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 2/6] drm/msm/dp: reduce link rate if failed at link training 1 Date: Thu, 5 Aug 2021 13:44:51 -0700 Message-Id: <1628196295-7382-3-git-send-email-khsieh@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1628196295-7382-1-git-send-email-khsieh@codeaurora.org> References: <1628196295-7382-1-git-send-email-khsieh@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org 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. Changes in V2: -- replaced cr_status with link_status[DP_LINK_STATUS_SIZE] -- replaced dp_ctrl_any_lane_cr_done() with dp_ctrl_colco_recovery_any_ok() -- replaced dp_ctrl_any_ane_cr_lose() with !drm_dp_clock_recovery_ok() Changes in V3: -- return failed if lane_count <= 1 Signed-off-by: Kuogee Hsieh Reviewed-by: Stephen Boyd --- drivers/gpu/drm/msm/dp/dp_ctrl.c | 79 +++++++++++++++++++++++----------------- 1 file changed, 45 insertions(+), 34 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 27fb0f0..0002805 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) + int *training_step) { int tries, old_v_level, ret = 0; u8 link_status[DP_LINK_STATUS_SIZE]; @@ -1109,9 +1102,6 @@ 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]; - if (drm_dp_clock_recovery_ok(link_status, ctrl->link->link_params.num_lanes)) { return 0; @@ -1188,7 +1178,7 @@ 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) + int *training_step) { int tries = 0, ret = 0; char pattern; @@ -1204,10 +1194,6 @@ 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 +1206,6 @@ 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]; if (drm_dp_channel_eq_ok(link_status, ctrl->link->link_params.num_lanes)) { @@ -1241,7 +1225,7 @@ 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) + int *training_step) { int ret = 0; u8 encoding = DP_SET_ANSI_8B10B; @@ -1257,7 +1241,7 @@ 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); - ret = dp_ctrl_link_train_1(ctrl, cr, training_step); + ret = dp_ctrl_link_train_1(ctrl, training_step); if (ret) { DRM_ERROR("link training #1 failed. ret=%d\n", ret); goto end; @@ -1266,7 +1250,7 @@ static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl, /* print success info as this is a result of user initiated action */ DRM_DEBUG_DP("link training #1 successful\n"); - ret = dp_ctrl_link_train_2(ctrl, cr, training_step); + ret = dp_ctrl_link_train_2(ctrl, training_step); if (ret) { DRM_ERROR("link training #2 failed. ret=%d\n", ret); goto end; @@ -1282,7 +1266,7 @@ 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) + int *training_step) { int ret = 0; @@ -1297,7 +1281,7 @@ static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl, * a link training pattern, we have to first do soft reset. */ - ret = dp_ctrl_link_train(ctrl, cr, training_step); + ret = dp_ctrl_link_train(ctrl, training_step); return ret; } @@ -1496,14 +1480,13 @@ 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; 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, &training_step); if (ret) goto end; @@ -1634,6 +1617,25 @@ void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl) } } +static bool dp_ctrl_clock_recovery_any_ok( + const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count) +{ + int reduced_cnt; + + if (lane_count <= 1) + return false; + + /* + * only interested in the lane number after reduced + * lane_count = 4, then only interested in 2 lanes + * lane_count = 2, then only interested in 1 lane + */ + reduced_cnt = lane_count >> 1; + + return drm_dp_clock_recovery_ok(link_status, reduced_cnt); +} + int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) { int rc = 0; @@ -1641,7 +1643,8 @@ 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]; + u8 link_status[DP_LINK_STATUS_SIZE]; unsigned int training_step; if (!dp_ctrl) @@ -1681,19 +1684,21 @@ 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, &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; - } + + dp_ctrl_read_link_status(ctrl, link_status); 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_clock_recovery_any_ok(link_status, + ctrl->link->link_params.num_lanes)) { /* * some lanes are ready, * reduce lane number @@ -1709,12 +1714,18 @@ 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); + dp_ctrl_read_link_status(ctrl, link_status); + + if (!drm_dp_clock_recovery_ok(link_status, + ctrl->link->link_params.num_lanes)) + 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 */