From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753298AbeCNFwf (ORCPT ); Wed, 14 Mar 2018 01:52:35 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:44594 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751155AbeCNFwd (ORCPT ); Wed, 14 Mar 2018 01:52:33 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3476460592 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=architt@codeaurora.org Subject: Re: [PATCH v5 05/36] drm/bridge: analogix_dp: add fast link train for eDP To: Enric Balletbo i Serra , inki.dae@samsung.com, thierry.reding@gmail.com, hjc@rock-chips.com, seanpaul@chromium.org, airlied@linux.ie, tfiga@chromium.org, heiko@sntech.de Cc: dri-devel@lists.freedesktop.org, dianders@chromium.org, a.hajda@samsung.com, ykk@rock-chips.com, kernel@collabora.com, m.szyprowski@samsung.com, linux-samsung-soc@vger.kernel.org, jy0922.shim@samsung.com, rydberg@bitmath.org, krzk@kernel.org, linux-rockchip@lists.infradead.org, kgene@kernel.org, linux-input@vger.kernel.org, orjan.eide@arm.com, wxt@rock-chips.com, jeffy.chen@rock-chips.com, linux-arm-kernel@lists.infradead.org, mark.yao@rock-chips.com, wzz@rock-chips.com, hl@rock-chips.com, jingoohan1@gmail.com, sw0312.kim@samsung.com, linux-kernel@vger.kernel.org, kyungmin.park@samsung.com, Laurent.pinchart@ideasonboard.com, kuankuan.y@gmail.com, hshi@chromium.org References: <20180309222327.18689-1-enric.balletbo@collabora.com> <20180309222327.18689-6-enric.balletbo@collabora.com> From: Archit Taneja Message-ID: <912773b9-e72b-11d1-e459-bbd765451f3c@codeaurora.org> Date: Wed, 14 Mar 2018 11:22:16 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180309222327.18689-6-enric.balletbo@collabora.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 10 March 2018 03:52 AM, Enric Balletbo i Serra wrote: > From: zain wang > > We would meet a short black screen when exit PSR with the full link > training, In this case, we should use fast link train instead of full > link training. > > Signed-off-by: zain wang > Signed-off-by: Sean Paul > Signed-off-by: Thierry Escande > Signed-off-by: Enric Balletbo i Serra > Tested-by: Marek Szyprowski > --- > > drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 142 ++++++++++++++++----- > drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 3 + > 2 files changed, 114 insertions(+), 31 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > index ee00d3d920e0..806c3878b3d6 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > @@ -10,17 +10,18 @@ > * option) any later version. > */ > > -#include > -#include > -#include > #include > -#include > +#include > +#include > +#include > #include > +#include > +#include > +#include > #include > #include > -#include > -#include > #include > +#include This re-ordering doesn't seem like it should be a part of this patch, you can let it stay if it happens to cause conflicts with future patches. Other than that: Reviewed-by: Archit Taneja Thanks, Archit > > #include > #include > @@ -35,6 +36,8 @@ > > #define to_dp(nm) container_of(nm, struct analogix_dp_device, nm) > > +static const bool verify_fast_training; > + > struct bridge_init { > struct i2c_client *client; > struct device_node *node; > @@ -528,7 +531,7 @@ static int analogix_dp_process_equalizer_training(struct analogix_dp_device *dp) > { > int lane, lane_count, retval; > u32 reg; > - u8 link_align, link_status[2], adjust_request[2]; > + u8 link_align, link_status[2], adjust_request[2], spread; > > usleep_range(400, 401); > > @@ -571,6 +574,20 @@ static int analogix_dp_process_equalizer_training(struct analogix_dp_device *dp) > dev_dbg(dp->dev, "final lane count = %.2x\n", > dp->link_train.lane_count); > > + retval = drm_dp_dpcd_readb(&dp->aux, DP_MAX_DOWNSPREAD, > + &spread); > + if (retval != 1) { > + dev_err(dp->dev, "failed to read downspread %d\n", > + retval); > + dp->fast_train_support = false; > + } else { > + dp->fast_train_support = > + (spread & DP_NO_AUX_HANDSHAKE_LINK_TRAINING) ? > + true : false; > + } > + dev_dbg(dp->dev, "fast link training %s\n", > + dp->fast_train_support ? "supported" : "unsupported"); > + > /* set enhanced mode if available */ > analogix_dp_set_enhanced_mode(dp); > dp->link_train.lt_state = FINISHED; > @@ -627,10 +644,12 @@ static void analogix_dp_get_max_rx_lane_count(struct analogix_dp_device *dp, > *lane_count = DPCD_MAX_LANE_COUNT(data); > } > > -static void analogix_dp_init_training(struct analogix_dp_device *dp, > - enum link_lane_count_type max_lane, > - int max_rate) > +static int analogix_dp_full_link_train(struct analogix_dp_device *dp, > + u32 max_lanes, u32 max_rate) > { > + int retval = 0; > + bool training_finished = false; > + > /* > * MACRO_RST must be applied after the PLL_LOCK to avoid > * the DP inter pair skew issue for at least 10 us > @@ -656,18 +675,13 @@ static void analogix_dp_init_training(struct analogix_dp_device *dp, > } > > /* Setup TX lane count & rate */ > - if (dp->link_train.lane_count > max_lane) > - dp->link_train.lane_count = max_lane; > + if (dp->link_train.lane_count > max_lanes) > + dp->link_train.lane_count = max_lanes; > if (dp->link_train.link_rate > max_rate) > dp->link_train.link_rate = max_rate; > > /* All DP analog module power up */ > analogix_dp_set_analog_power_down(dp, POWER_ALL, 0); > -} > - > -static int analogix_dp_sw_link_training(struct analogix_dp_device *dp) > -{ > - int retval = 0, training_finished = 0; > > dp->link_train.lt_state = START; > > @@ -702,22 +716,88 @@ static int analogix_dp_sw_link_training(struct analogix_dp_device *dp) > return retval; > } > > -static int analogix_dp_set_link_train(struct analogix_dp_device *dp, > - u32 count, u32 bwtype) > +static int analogix_dp_fast_link_train(struct analogix_dp_device *dp) > { > - int i; > - int retval; > + int i, ret; > + u8 link_align, link_status[2]; > + enum pll_status status; > > - for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) { > - analogix_dp_init_training(dp, count, bwtype); > - retval = analogix_dp_sw_link_training(dp); > - if (retval == 0) > - break; > + analogix_dp_reset_macro(dp); > + > + analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate); > + analogix_dp_set_lane_count(dp, dp->link_train.lane_count); > > - usleep_range(100, 110); > + for (i = 0; i < dp->link_train.lane_count; i++) { > + analogix_dp_set_lane_link_training(dp, > + dp->link_train.training_lane[i], i); > } > > - return retval; > + ret = readx_poll_timeout(analogix_dp_get_pll_lock_status, dp, status, > + status != PLL_UNLOCKED, 120, > + 120 * DP_TIMEOUT_LOOP_COUNT); > + if (ret) { > + DRM_DEV_ERROR(dp->dev, "Wait for pll lock failed %d\n", ret); > + return ret; > + } > + > + /* source Set training pattern 1 */ > + analogix_dp_set_training_pattern(dp, TRAINING_PTN1); > + /* From DP spec, pattern must be on-screen for a minimum 500us */ > + usleep_range(500, 600); > + > + analogix_dp_set_training_pattern(dp, TRAINING_PTN2); > + /* From DP spec, pattern must be on-screen for a minimum 500us */ > + usleep_range(500, 600); > + > + /* TODO: enhanced_mode?*/ > + analogix_dp_set_training_pattern(dp, DP_NONE); > + > + /* > + * Useful for debugging issues with fast link training, disable for more > + * speed > + */ > + if (verify_fast_training) { > + ret = drm_dp_dpcd_readb(&dp->aux, DP_LANE_ALIGN_STATUS_UPDATED, > + &link_align); > + if (ret < 0) { > + DRM_DEV_ERROR(dp->dev, "Read align status failed %d\n", > + ret); > + return ret; > + } > + > + ret = drm_dp_dpcd_read(&dp->aux, DP_LANE0_1_STATUS, link_status, > + 2); > + if (ret < 0) { > + DRM_DEV_ERROR(dp->dev, "Read link status failed %d\n", > + ret); > + return ret; > + } > + > + if (analogix_dp_clock_recovery_ok(link_status, > + dp->link_train.lane_count)) { > + DRM_DEV_ERROR(dp->dev, "Clock recovery failed\n"); > + analogix_dp_reduce_link_rate(dp); > + return -EIO; > + } > + > + if (analogix_dp_channel_eq_ok(link_status, link_align, > + dp->link_train.lane_count)) { > + DRM_DEV_ERROR(dp->dev, "Channel EQ failed\n"); > + analogix_dp_reduce_link_rate(dp); > + return -EIO; > + } > + } > + > + return 0; > +} > + > +static int analogix_dp_train_link(struct analogix_dp_device *dp) > +{ > + if (dp->fast_train_support) > + return analogix_dp_fast_link_train(dp); > + > + return analogix_dp_full_link_train(dp, dp->video_info.max_lane_count, > + dp->video_info.max_link_rate); > } > > static int analogix_dp_config_video(struct analogix_dp_device *dp) > @@ -846,10 +926,10 @@ static void analogix_dp_commit(struct analogix_dp_device *dp) > DRM_ERROR("failed to disable the panel\n"); > } > > - ret = analogix_dp_set_link_train(dp, dp->video_info.max_lane_count, > - dp->video_info.max_link_rate); > + ret = readx_poll_timeout(analogix_dp_train_link, dp, ret, !ret, 100, > + DP_TIMEOUT_TRAINING_US * 5); > if (ret) { > - dev_err(dp->dev, "unable to do link train\n"); > + dev_err(dp->dev, "unable to do link train, ret=%d\n", ret); > return; > } > > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > index e135a42cb19e..920607d7eb3e 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > @@ -20,6 +20,8 @@ > #define MAX_CR_LOOP 5 > #define MAX_EQ_LOOP 5 > > +/* Training takes 22ms if AUX channel comm fails. Use this as retry interval */ > +#define DP_TIMEOUT_TRAINING_US 22000 > #define DP_TIMEOUT_PSR_LOOP_MS 300 > > /* DP_MAX_LANE_COUNT */ > @@ -171,6 +173,7 @@ struct analogix_dp_device { > int hpd_gpio; > bool force_hpd; > bool psr_enable; > + bool fast_train_support; > > struct mutex panel_lock; > bool panel_is_modeset; >