From patchwork Mon Nov 18 14:28:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongbang Shi X-Patchwork-Id: 13878689 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A099ED4921D for ; Mon, 18 Nov 2024 14:33:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EC6B810E004; Mon, 18 Nov 2024 14:33:52 +0000 (UTC) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2A65D10E004 for ; Mon, 18 Nov 2024 14:33:51 +0000 (UTC) Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4XsVRZ32Ddz9248; Mon, 18 Nov 2024 22:31:06 +0800 (CST) Received: from kwepemd500013.china.huawei.com (unknown [7.221.188.12]) by mail.maildlp.com (Postfix) with ESMTPS id E7B8B180104; Mon, 18 Nov 2024 22:33:48 +0800 (CST) Received: from localhost.huawei.com (10.169.71.169) by kwepemd500013.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Mon, 18 Nov 2024 22:33:47 +0800 From: Yongbang Shi To: , , , , , , , CC: , , , , , , , , Subject: [PATCH v5 drm-dp 2/5] drm/hisilicon/hibmc: add dp link moduel in hibmc Date: Mon, 18 Nov 2024 22:28:02 +0800 Message-ID: <20241118142805.3326443-3-shiyongbang@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20241118142805.3326443-1-shiyongbang@huawei.com> References: <20241118142805.3326443-1-shiyongbang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.169.71.169] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemd500013.china.huawei.com (7.221.188.12) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: baihan li Add link training process functions in this moduel. Signed-off-by: Baihan Li Signed-off-by: Yongbang Shi --- Changelog: v3 -> v4: - optimizing hibmc_dp_link_get_adjust_train() to delete for loop, suggested by Dmitry Baryshkov. - changing ELNRNG to EIO error code, suggested by Dmitry Baryshkov. - deleting meaningless macro, suggested by Dmitry Baryshkov. - fixing build errors reported by kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202411041559.WIfxRN6n-lkp@intel.com/ v2 -> v3: - using switchcase in dp_link_reduce_lane, suggested by Dmitry Baryshkov. - deleting dp_link_pattern2dpcd function and using macros directly, suggested by Dmitry Baryshkov. - deleting EFAULT error codes, suggested by Dmitry Baryshkov. v1 -> v2: - using drm_dp_* functions implement dp link training process, suggested by Jani Nikula. - fix build errors reported by kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202410031735.8iRZZR6T-lkp@intel.com/ v1:https://lore.kernel.org/all/20240930100610.782363-1-shiyongbang@huawei.com/ --- drivers/gpu/drm/hisilicon/hibmc/Makefile | 2 +- drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h | 24 ++ drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c | 339 +++++++++++++++++++ drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h | 8 + 4 files changed, 372 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c diff --git a/drivers/gpu/drm/hisilicon/hibmc/Makefile b/drivers/gpu/drm/hisilicon/hibmc/Makefile index 8770ec6dfffd..94d77da88bbf 100644 --- a/drivers/gpu/drm/hisilicon/hibmc/Makefile +++ b/drivers/gpu/drm/hisilicon/hibmc/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_de.o hibmc_drm_vdac.o hibmc_drm_i2c.o \ - dp/dp_aux.o + dp/dp_aux.o dp/dp_link.o obj-$(CONFIG_DRM_HISI_HIBMC) += hibmc-drm.o diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h index ce3b6fa4ea9e..8553e531ba67 100644 --- a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h @@ -13,11 +13,34 @@ #include #include +#define HIBMC_DP_LANE_NUM_MAX 2 + +struct hibmc_link_status { + bool clock_recovered; + bool channel_equalized; +}; + +struct hibmc_link_cap { + int rx_dpcd_revision; + u8 link_rate; + u8 lanes; + bool is_tps3; + bool is_tps4; +}; + +struct hibmc_dp_link { + struct hibmc_link_status status; + u8 train_set[HIBMC_DP_LANE_NUM_MAX]; + struct hibmc_link_cap cap; +}; + struct hibmc_dp_dev { struct drm_dp_aux aux; struct drm_device *dev; void __iomem *base; struct mutex lock; /* protects concurrent RW in hibmc_dp_reg_write_field() */ + struct hibmc_dp_link link; + u8 dpcd[DP_RECEIVER_CAP_SIZE]; }; #define dp_field_modify(reg_value, mask, val) ({ \ @@ -34,5 +57,6 @@ struct hibmc_dp_dev { mutex_unlock(&_dp->lock); }) void hibmc_dp_aux_init(struct hibmc_dp_dev *dp); +int hibmc_dp_link_training(struct hibmc_dp_dev *dp); #endif diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c new file mode 100644 index 000000000000..b7ae9e54126c --- /dev/null +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c @@ -0,0 +1,339 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// Copyright (c) 2024 Hisilicon Limited. + +#include +#include +#include +#include "dp_comm.h" +#include "dp_reg.h" + +#define HIBMC_EQ_MAX_RETRY 5 + +static int hibmc_dp_link_training_configure(struct hibmc_dp_dev *dp) +{ + u8 buf[2]; + int ret; + + /* DP 2 lane */ + hibmc_dp_reg_write_field(dp, HIBMC_DP_PHYIF_CTRL0, HIBMC_DP_CFG_LANE_DATA_EN, + dp->link.cap.lanes == 0x2 ? 0x3 : 0x1); + hibmc_dp_reg_write_field(dp, HIBMC_DP_DPTX_GCTL0, HIBMC_DP_CFG_PHY_LANE_NUM, + dp->link.cap.lanes == 0x2 ? 0x1 : 0); + + /* enhanced frame */ + hibmc_dp_reg_write_field(dp, HIBMC_DP_VIDEO_CTRL, HIBMC_DP_CFG_STREAM_FRAME_MODE, 0x1); + + /* set rate and lane count */ + buf[0] = dp->link.cap.link_rate; + buf[1] = DP_LANE_COUNT_ENHANCED_FRAME_EN | dp->link.cap.lanes; + ret = drm_dp_dpcd_write(&dp->aux, DP_LINK_BW_SET, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + drm_dbg_dp(dp->dev, "dp aux write link rate and lanes failed, ret: %d\n", ret); + return ret >= 0 ? -EIO : ret; + } + + /* set 8b/10b and downspread */ + buf[0] = 0x10; + buf[1] = 0x1; + ret = drm_dp_dpcd_write(&dp->aux, DP_DOWNSPREAD_CTRL, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + drm_dbg_dp(dp->dev, "dp aux write 8b/10b and downspread failed, ret: %d\n", ret); + return ret >= 0 ? -EIO : ret; + } + + ret = drm_dp_read_dpcd_caps(&dp->aux, dp->dpcd); + if (ret) + drm_err(dp->dev, "dp aux read dpcd failed, ret: %d\n", ret); + + return ret; +} + +static int hibmc_dp_link_set_pattern(struct hibmc_dp_dev *dp, int pattern) +{ + int ret; + u8 val; + u8 buf; + + buf = (u8)pattern; + if (pattern != DP_TRAINING_PATTERN_DISABLE && pattern != DP_TRAINING_PATTERN_4) { + buf |= DP_LINK_SCRAMBLING_DISABLE; + hibmc_dp_reg_write_field(dp, HIBMC_DP_PHYIF_CTRL0, HIBMC_DP_CFG_SCRAMBLE_EN, 0x1); + } else { + hibmc_dp_reg_write_field(dp, HIBMC_DP_PHYIF_CTRL0, HIBMC_DP_CFG_SCRAMBLE_EN, 0); + } + + switch (pattern) { + case DP_TRAINING_PATTERN_1: + val = 1; + break; + case DP_TRAINING_PATTERN_2: + val = 2; + break; + case DP_TRAINING_PATTERN_3: + val = 3; + break; + case DP_TRAINING_PATTERN_4: + val = 4; + break; + default: + return -EINVAL; + } + + hibmc_dp_reg_write_field(dp, HIBMC_DP_PHYIF_CTRL0, HIBMC_DP_CFG_PAT_SEL, val); + + ret = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_PATTERN_SET, &buf, sizeof(buf)); + if (ret != sizeof(buf)) { + drm_dbg_dp(dp->dev, "dp aux write training pattern set failed\n"); + return ret >= 0 ? -EIO : ret; + } + + return 0; +} + +static int hibmc_dp_link_training_cr_pre(struct hibmc_dp_dev *dp) +{ + u8 *train_set = dp->link.train_set; + int ret; + u8 i; + + ret = hibmc_dp_link_training_configure(dp); + if (ret) + return ret; + + ret = hibmc_dp_link_set_pattern(dp, DP_TRAINING_PATTERN_1); + if (ret) + return ret; + + for (i = 0; i < dp->link.cap.lanes; i++) + train_set[i] = DP_TRAIN_VOLTAGE_SWING_LEVEL_2; + + ret = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, train_set, dp->link.cap.lanes); + if (ret != dp->link.cap.lanes) { + drm_dbg_dp(dp->dev, "dp aux write training lane set failed\n"); + return ret >= 0 ? -EIO : ret; + } + + return 0; +} + +static bool hibmc_dp_link_get_adjust_train(struct hibmc_dp_dev *dp, + u8 lane_status[DP_LINK_STATUS_SIZE]) +{ + u8 train_set[HIBMC_DP_LANE_NUM_MAX] = {0}; + u8 lane; + + for (lane = 0; lane < dp->link.cap.lanes; lane++) + train_set[lane] = drm_dp_get_adjust_request_voltage(lane_status, lane) | + drm_dp_get_adjust_request_pre_emphasis(lane_status, lane); + + if (memcmp(dp->link.train_set, train_set, HIBMC_DP_LANE_NUM_MAX)) { + memcpy(dp->link.train_set, train_set, HIBMC_DP_LANE_NUM_MAX); + return true; + } + + return false; +} + +static inline int hibmc_dp_link_reduce_rate(struct hibmc_dp_dev *dp) +{ + switch (dp->link.cap.link_rate) { + case DP_LINK_BW_2_7: + dp->link.cap.link_rate = DP_LINK_BW_1_62; + return 0; + case DP_LINK_BW_5_4: + dp->link.cap.link_rate = DP_LINK_BW_2_7; + return 0; + case DP_LINK_BW_8_1: + dp->link.cap.link_rate = DP_LINK_BW_5_4; + return 0; + default: + return -EINVAL; + } +} + +static inline int hibmc_dp_link_reduce_lane(struct hibmc_dp_dev *dp) +{ + switch (dp->link.cap.lanes) { + case 0x2: + dp->link.cap.lanes--; + break; + case 0x1: + drm_err(dp->dev, "dp link training reduce lane failed, already reach minimum\n"); + return -EIO; + default: + return -EINVAL; + } + + return 0; +} + +static int hibmc_dp_link_training_cr(struct hibmc_dp_dev *dp) +{ + u8 lane_status[DP_LINK_STATUS_SIZE] = {0}; + bool level_changed; + u32 voltage_tries; + u32 cr_tries; + u32 max_cr; + int ret; + + /* + * DP 1.4 spec define 10 for maxtries value, for pre DP 1.4 version set a limit of 80 + * (4 voltage levels x 4 preemphasis levels x 5 identical voltage retries) + */ + max_cr = dp->link.cap.rx_dpcd_revision >= DP_DPCD_REV_14 ? 10 : 80; + + voltage_tries = 1; + for (cr_tries = 0; cr_tries < max_cr; cr_tries++) { + drm_dp_link_train_clock_recovery_delay(&dp->aux, dp->dpcd); + + ret = drm_dp_dpcd_read_link_status(&dp->aux, lane_status); + if (ret != DP_LINK_STATUS_SIZE) { + drm_err(dp->dev, "Get lane status failed\n"); + return ret; + } + + if (drm_dp_clock_recovery_ok(lane_status, dp->link.cap.lanes)) { + drm_info(dp->dev, "dp link training cr done\n"); + dp->link.status.clock_recovered = true; + return 0; + } + + if (voltage_tries == 5) { + drm_info(dp->dev, "same voltage tries 5 times\n"); + dp->link.status.clock_recovered = false; + return 0; + } + + level_changed = hibmc_dp_link_get_adjust_train(dp, lane_status); + ret = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, dp->link.train_set, + dp->link.cap.lanes); + if (ret != dp->link.cap.lanes) { + drm_dbg_dp(dp->dev, "Update link training failed\n"); + return ret >= 0 ? -EIO : ret; + } + + voltage_tries = level_changed ? 1 : voltage_tries + 1; + } + + drm_err(dp->dev, "dp link training clock recovery %u timers failed\n", max_cr); + dp->link.status.clock_recovered = false; + + return 0; +} + +static int hibmc_dp_link_training_channel_eq(struct hibmc_dp_dev *dp) +{ + u8 lane_status[DP_LINK_STATUS_SIZE] = {0}; + u8 eq_tries; + int tps; + int ret; + + if (dp->link.cap.is_tps4) + tps = DP_TRAINING_PATTERN_4; + else if (dp->link.cap.is_tps3) + tps = DP_TRAINING_PATTERN_3; + else + tps = DP_TRAINING_PATTERN_2; + + ret = hibmc_dp_link_set_pattern(dp, tps); + if (ret) + return ret; + + for (eq_tries = 0; eq_tries < HIBMC_EQ_MAX_RETRY; eq_tries++) { + drm_dp_link_train_channel_eq_delay(&dp->aux, dp->dpcd); + + ret = drm_dp_dpcd_read_link_status(&dp->aux, lane_status); + if (ret != DP_LINK_STATUS_SIZE) { + drm_err(dp->dev, "get lane status failed\n"); + break; + } + + if (!drm_dp_clock_recovery_ok(lane_status, dp->link.cap.lanes)) { + drm_info(dp->dev, "clock recovery check failed\n"); + drm_info(dp->dev, "cannot continue channel equalization\n"); + dp->link.status.clock_recovered = false; + break; + } + + if (drm_dp_channel_eq_ok(lane_status, dp->link.cap.lanes)) { + dp->link.status.channel_equalized = true; + drm_info(dp->dev, "dp link training eq done\n"); + break; + } + + hibmc_dp_link_get_adjust_train(dp, lane_status); + ret = drm_dp_dpcd_write(&dp->aux, DP_TRAINING_LANE0_SET, + dp->link.train_set, dp->link.cap.lanes); + if (ret != dp->link.cap.lanes) { + drm_dbg_dp(dp->dev, "Update link training failed\n"); + ret = (ret >= 0) ? -EIO : ret; + break; + } + } + + if (eq_tries == HIBMC_EQ_MAX_RETRY) + drm_err(dp->dev, "channel equalization failed %u times\n", eq_tries); + + hibmc_dp_link_set_pattern(dp, DP_TRAINING_PATTERN_DISABLE); + + return ret < 0 ? ret : 0; +} + +static int hibmc_dp_link_downgrade_training_cr(struct hibmc_dp_dev *dp) +{ + if (hibmc_dp_link_reduce_rate(dp)) + return hibmc_dp_link_reduce_lane(dp); + + return 0; +} + +static int hibmc_dp_link_downgrade_training_eq(struct hibmc_dp_dev *dp) +{ + if ((dp->link.status.clock_recovered && !dp->link.status.channel_equalized)) { + if (!hibmc_dp_link_reduce_lane(dp)) + return 0; + } + + return hibmc_dp_link_reduce_rate(dp); +} + +int hibmc_dp_link_training(struct hibmc_dp_dev *dp) +{ + struct hibmc_dp_link *link = &dp->link; + int ret; + + while (true) { + ret = hibmc_dp_link_training_cr_pre(dp); + if (ret) + goto err; + + ret = hibmc_dp_link_training_cr(dp); + if (ret) + goto err; + + if (!link->status.clock_recovered) { + ret = hibmc_dp_link_downgrade_training_cr(dp); + if (ret) + goto err; + continue; + } + + ret = hibmc_dp_link_training_channel_eq(dp); + if (ret) + goto err; + + if (!link->status.channel_equalized) { + ret = hibmc_dp_link_downgrade_training_eq(dp); + if (ret) + goto err; + continue; + } + + return 0; + } + +err: + hibmc_dp_link_set_pattern(dp, DP_TRAINING_PATTERN_DISABLE); + + return ret; +} diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h index f3e6781e111a..0bd308eccdc5 100644 --- a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h @@ -12,16 +12,24 @@ #define HIBMC_DP_AUX_RD_DATA0 0x64 #define HIBMC_DP_AUX_REQ 0x74 #define HIBMC_DP_AUX_STATUS 0x78 +#define HIBMC_DP_PHYIF_CTRL0 0xa0 +#define HIBMC_DP_VIDEO_CTRL 0x100 #define HIBMC_DP_DPTX_RST_CTRL 0x700 +#define HIBMC_DP_DPTX_GCTL0 0x708 #define HIBMC_DP_CFG_AUX_SYNC_LEN_SEL BIT(1) #define HIBMC_DP_CFG_AUX_TIMER_TIMEOUT BIT(2) +#define HIBMC_DP_CFG_STREAM_FRAME_MODE BIT(6) #define HIBMC_DP_CFG_AUX_MIN_PULSE_NUM GENMASK(13, 9) +#define HIBMC_DP_CFG_LANE_DATA_EN GENMASK(11, 8) +#define HIBMC_DP_CFG_PHY_LANE_NUM GENMASK(2, 1) #define HIBMC_DP_CFG_AUX_REQ BIT(0) #define HIBMC_DP_CFG_AUX_RST_N BIT(4) #define HIBMC_DP_CFG_AUX_TIMEOUT BIT(0) #define HIBMC_DP_CFG_AUX_READY_DATA_BYTE GENMASK(16, 12) #define HIBMC_DP_CFG_AUX GENMASK(24, 17) #define HIBMC_DP_CFG_AUX_STATUS GENMASK(11, 4) +#define HIBMC_DP_CFG_SCRAMBLE_EN BIT(0) +#define HIBMC_DP_CFG_PAT_SEL GENMASK(7, 4) #endif