From: baihan li <libaihan@xxxxxxxxxx>
Add link training process functions in this moduel.
Signed-off-by: baihan li <libaihan@xxxxxxxxxx>
---
drivers/gpu/drm/hisilicon/hibmc/Makefile | 2 +-
drivers/gpu/drm/hisilicon/hibmc/dp/dp_kapi.c | 258 ++++++++++++
drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c | 390 +++++++++++++++++++
drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.h | 24 ++
4 files changed, 673 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_kapi.c
create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c
create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.h
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_kapi.c b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_kapi.c
new file mode 100644
index 000000000000..4091723473ad
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_kapi.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (c) 2024 Hisilicon Limited.
+
+#include <linux/io.h>
+#include <linux/delay.h>
+#include "dp_config.h"
+#include "dp_comm.h"
+#include "dp_reg.h"
+#include "dp_kapi.h"
+#include "dp_link.h"
+
+#define DP_LINK_RATE_HBR 0xa
+
+static int hibmc_dp_link_init(struct hibmc_dp_dev *dp)
+{
+ dp->link.cap.lanes = 2;
+ dp->link.train_set = devm_kzalloc(dp->dev->dev,
+ dp->link.cap.lanes * sizeof(u8), GFP_KERNEL);
+ if (!dp->link.train_set)
+ return -ENOMEM;
+
+ dp->link.cap.link_rate = DP_LINK_RATE_HBR;
+
+ return 0;
+}
+
+static void hibmc_dp_aux_init(struct hibmc_dp_dev *dp)
+{
+ struct hibmc_dp_aux *aux = &dp->aux;
+
+ aux->addr = dp->base;
+ /* aux read/write lock */
+ mutex_init(&aux->lock);
+ dp_write_bits(aux->addr + DP_AUX_REQ, DP_CFG_AUX_SYNC_LEN_SEL, 0x0);
+ dp_write_bits(aux->addr + DP_AUX_REQ, DP_CFG_AUX_TIMER_TIMEOUT, 0x1);
+ dp_write_bits(aux->addr + DP_AUX_REQ, DP_CFG_AUX_MIN_PULSE_NUM, DP_MIN_PULSE_NUM);
+}
+
+static void hibmc_dp_aux_uninit(struct hibmc_dp_dev *dp)
+{
+ struct hibmc_dp_aux *aux = &dp->aux;
+
+ mutex_destroy(&aux->lock);
+}
+
+static void hibmc_dp_set_tu(struct hibmc_dp_dev *dp, struct dp_mode *mode)
+{
+ u32 tu_symbol_frac_size;
+ u32 tu_symbol_size;
+ u64 pixel_clock;
+ u64 rate_ks;
+ u8 lane_num;
+ u32 value;
+ u32 bpp;
+
+ pixel_clock = mode->pixel_clock;
+ lane_num = dp->link.cap.lanes;
+ if (lane_num == 0) {
+ drm_err(dp->dev, "set tu failed, lane num cannot be 0!\n");
+ return;
+ }
+
+ bpp = DP_BPP;
+ rate_ks = dp->link.cap.link_rate * DP_LINK_RATE_CAL;
+ value = (pixel_clock * bpp * 5000) / (61 * lane_num * rate_ks);
+
+ if (value % 10 == 9) { /* 10: div, 9: carry */
+ tu_symbol_size = value / 10 + 1; /* 10: div */
+ tu_symbol_frac_size = 0;
+ } else {
+ tu_symbol_size = value / 10; /* 10: div */
+ tu_symbol_frac_size = value % 10 + 1; /* 10: div */
+ }
+
+ drm_info(dp->dev, "tu value: %u.%u value: %u\n",
+ tu_symbol_size, tu_symbol_frac_size, value);
+
+ dp_write_bits(dp->base + DP_VIDEO_PACKET,
+ DP_CFG_STREAM_TU_SYMBOL_SIZE, tu_symbol_size);
+ dp_write_bits(dp->base + DP_VIDEO_PACKET,
+ DP_CFG_STREAM_TU_SYMBOL_FRAC_SIZE, tu_symbol_frac_size);
+}
+
+static void hibmc_dp_set_sst(struct hibmc_dp_dev *dp, struct dp_mode *mode)
+{
+ u32 hblank_size;
+ u32 htotal_size;
+ u32 htotal_int;
+ u32 hblank_int;
+ u32 fclk; /* flink_clock */
+
+ fclk = dp->link.cap.link_rate * DP_LINK_RATE_CAL;
+
+ /* ssc: 9947 / 10000 = 0.9947 */
+ htotal_int = mode->h_total * 9947 / 10000;
+ htotal_size = (u32)((u64)htotal_int * fclk / (DP_SYMBOL_PER_FCLK * mode->pixel_clock));
+
+ /* ssc: max effect bandwidth 53 / 10000 = 0.53% */
+ hblank_int = mode->h_blank - mode->h_active * 53 / 10000;
+ hblank_size = (u64)hblank_int * fclk * 9947 /
+ ((u64)mode->pixel_clock * 10000 * DP_SYMBOL_PER_FCLK);
+
+ drm_info(dp->dev, "h_active %u v_active %u htotal_size %u hblank_size %u",
+ mode->h_active, mode->v_active, htotal_size, hblank_size);
+ drm_info(dp->dev, "flink_clock %u pixel_clock %u", fclk, mode->pixel_clock);
+
+ dp_write_bits(dp->base + DP_VIDEO_HORIZONTAL_SIZE, DP_CFG_STREAM_HTOTAL_SIZE, htotal_size);
+ dp_write_bits(dp->base + DP_VIDEO_HORIZONTAL_SIZE, DP_CFG_STREAM_HBLANK_SIZE, hblank_size);
+}
+
+static void hibmc_dp_link_cfg(struct hibmc_dp_dev *dp, struct dp_mode *mode)
+{
+ u32 timing_delay;
+ u32 vblank;
+ u32 hstart;
+ u32 vstart;
+
+ vblank = mode->v_total - mode->v_active;
+ timing_delay = mode->h_sync + mode->h_back;
+ hstart = mode->h_sync + mode->h_back;
+ vstart = mode->v_sync + mode->v_back;
+
+ dp_write_bits(dp->base + DP_TIMING_GEN_CONFIG0,
+ DP_CFG_TIMING_GEN0_HBLANK, mode->h_blank);
+ dp_write_bits(dp->base + DP_TIMING_GEN_CONFIG0,
+ DP_CFG_TIMING_GEN0_HACTIVE, mode->h_active);
+
+ dp_write_bits(dp->base + DP_TIMING_GEN_CONFIG2,
+ DP_CFG_TIMING_GEN0_VBLANK, vblank);
+ dp_write_bits(dp->base + DP_TIMING_GEN_CONFIG2,
+ DP_CFG_TIMING_GEN0_VACTIVE, mode->v_active);
+ dp_write_bits(dp->base + DP_TIMING_GEN_CONFIG3,
+ DP_CFG_TIMING_GEN0_VFRONT_PORCH, mode->v_front);
+
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG0,
+ DP_CFG_STREAM_HACTIVE, mode->h_active);
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG0,
+ DP_CFG_STREAM_HBLANK, mode->h_blank);
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG2,
+ DP_CFG_STREAM_HSYNC_WIDTH, mode->h_sync);
+
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG1,
+ DP_CFG_STREAM_VACTIVE, mode->v_active);
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG1,
+ DP_CFG_STREAM_VBLANK, vblank);
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG3,
+ DP_CFG_STREAM_VFRONT_PORCH, mode->v_front);
+ dp_write_bits(dp->base + DP_VIDEO_CONFIG3,
+ DP_CFG_STREAM_VSYNC_WIDTH, mode->v_sync);
+
+ dp_write_bits(dp->base + DP_VIDEO_MSA0,
+ DP_CFG_STREAM_VSTART, vstart);
+ dp_write_bits(dp->base + DP_VIDEO_MSA0,
+ DP_CFG_STREAM_HSTART, hstart);
+
+ dp_write_bits(dp->base + DP_VIDEO_CTRL,
+ DP_CFG_STREAM_VSYNC_POLARITY, mode->v_pol);
+ dp_write_bits(dp->base + DP_VIDEO_CTRL,
+ DP_CFG_STREAM_HSYNC_POLARITY, mode->h_pol);
+
+ /* MSA mic 0 and 1*/
+ writel(DP_MSA1, dp->base + DP_VIDEO_MSA1);
+ writel(DP_MSA2, dp->base + DP_VIDEO_MSA2);
+
+ hibmc_dp_set_tu(dp, mode);
+
+ dp_write_bits(dp->base + DP_VIDEO_CTRL, DP_CFG_STREAM_RGB_ENABLE, 0x1);
+ dp_write_bits(dp->base + DP_VIDEO_CTRL, DP_CFG_STREAM_VIDEO_MAPPING, 0);
+
+ /*divide 2: up even */
+ if (timing_delay % 2)
+ timing_delay++;
+
+ dp_write_bits(dp->base + DP_TIMING_MODEL_CTRL,
+ DP_CFG_PIXEL_NUM_TIMING_MODE_SEL1, timing_delay);
+
+ hibmc_dp_set_sst(dp, mode);
+}
+
+int hibmc_dp_kapi_init(struct hibmc_dp *dp)
+{
+ struct drm_device *drm_dev = dp->drm_dev;
+ struct hibmc_dp_dev *dp_dev;
+ int ret;
+
+ dp_dev = devm_kzalloc(drm_dev->dev, sizeof(struct hibmc_dp_dev), GFP_KERNEL);
+ if (!dp_dev)
+ return -ENOMEM;
+
+ dp->dp_dev = dp_dev;
+
+ dp_dev->dev = drm_dev;
+ dp_dev->base = dp->mmio + DP_OFFSET;
+
+ hibmc_dp_aux_init(dp_dev);
+
+ ret = hibmc_dp_link_init(dp_dev);
+ if (ret) {
+ drm_err(drm_dev, "dp link init failed\n");
+ hibmc_dp_aux_uninit(dp_dev);
+ return ret;
+ }
+
+ /* hdcp data */
+ writel(DP_HDCP, dp_dev->base + DP_HDCP_CFG);
+ /* int init */
+ writel(0, dp_dev->base + DP_INTR_ENABLE);
+ writel(DP_INT_RST, dp_dev->base + DP_INTR_ORIGINAL_STATUS);
+ /* rst */
+ writel(DP_DPTX_RST, dp_dev->base + DP_DPTX_RST_CTRL);
+ /* clock enable */
+ writel(DP_CLK_EN, dp_dev->base + DP_DPTX_CLK_CTRL);
+
+ return 0;
+}
+
+void hibmc_dp_kapi_uninit(struct hibmc_dp *dp)
+{
+ hibmc_dp_aux_uninit(dp->dp_dev);
+}
+
+void hibmc_dp_display_en(struct hibmc_dp *dp, bool enable)
+{
+ struct hibmc_dp_dev *dp_dev = dp->dp_dev;
+
+ if (enable) {
+ dp_write_bits(dp_dev->base + DP_VIDEO_CTRL, BIT(0), 0x1);
+ writel(DP_SYNC_EN_MASK, dp_dev->base + DP_TIMING_SYNC_CTRL);
+ dp_write_bits(dp_dev->base + DP_DPTX_GCTL0, BIT(10), 0x1);
+ writel(DP_SYNC_EN_MASK, dp_dev->base + DP_TIMING_SYNC_CTRL);
+ } else {
+ dp_write_bits(dp_dev->base + DP_DPTX_GCTL0, BIT(10), 0);
+ writel(DP_SYNC_EN_MASK, dp_dev->base + DP_TIMING_SYNC_CTRL);
+ dp_write_bits(dp_dev->base + DP_VIDEO_CTRL, BIT(0), 0);
+ writel(DP_SYNC_EN_MASK, dp_dev->base + DP_TIMING_SYNC_CTRL);
+ }
+
+ msleep(50);
+}
+
+int hibmc_dp_mode_set(struct hibmc_dp *dp, struct dp_mode *mode)
+{
+ struct hibmc_dp_dev *dp_dev = dp->dp_dev;
+ int ret;
+
+ if (!dp_dev->link.status.channel_equalized) {
+ ret = dp_link_training(dp_dev);
+ if (ret) {
+ drm_err(dp->drm_dev, "dp link training failed, ret: %d\n", ret);
+ return ret;
+ }
+ }
+
+ hibmc_dp_display_en(dp, false);
+ hibmc_dp_link_cfg(dp_dev, mode);
+
+ return 0;
+}
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..0a10cae1d8a4
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (c) 2024 Hisilicon Limited.
+
+#include <linux/delay.h>
+#include <drm/drm_device.h>
+#include <drm/drm_print.h>
+#include "dp_comm.h"
+#include "dp_reg.h"
+#include "dp_link.h"
+#include "dp_aux.h"
+
+static int dp_link_training_configure(struct hibmc_dp_dev *dp)
+{
+ u8 buf[2];
+ int ret;
+
+ /* DP 2 lane */
+ dp_write_bits(dp->base + DP_PHYIF_CTRL0, DP_CFG_LANE_DATA_EN,
+ dp->link.cap.lanes == DP_LANE_NUM_2 ? 0x3 : 0x1);
+ dp_write_bits(dp->base + DP_DPTX_GCTL0, DP_CFG_PHY_LANE_NUM,
+ dp->link.cap.lanes == DP_LANE_NUM_2 ? 0x1 : 0);
+
+ /* enhanced frame */
+ dp_write_bits(dp->base + DP_VIDEO_CTRL, DP_CFG_STREAM_FRAME_MODE, 0x1);
+
+ /* set rate and lane count */
+ buf[0] = dp->link.cap.link_rate;
+ buf[1] = DPCD_ENHANCED_FRAME_EN | dp->link.cap.lanes;
+ ret = dp_aux_write(dp, DPCD_LINK_BW_SET, buf, sizeof(buf));
+ if (ret) {
+ drm_err(dp->dev, "dp aux write link rate and lanes failed, ret: %d\n", ret);
+ return ret;
+ }
+
+ /* set 8b/10b and downspread */
+ buf[0] = 0x10;
+ buf[1] = 0x1;
+ ret = dp_aux_write(dp, DPCD_DOWNSPREAD_CTRL, buf, sizeof(buf));
+ if (ret)
+ drm_err(dp->dev, "dp aux write 8b/10b and downspread failed, ret: %d\n", ret);
+
+ return ret;
+}
+
+static int dp_link_pattern2dpcd(struct hibmc_dp_dev *dp, enum dp_pattern_e pattern)
+{
+ switch (pattern) {
+ case DP_PATTERN_NO:
+ return DPCD_TRAINING_PATTERN_DISABLE;
+ case DP_PATTERN_TPS1:
+ return DPCD_TRAINING_PATTERN_1;
+ case DP_PATTERN_TPS2:
+ return DPCD_TRAINING_PATTERN_2;
+ case DP_PATTERN_TPS3:
+ return DPCD_TRAINING_PATTERN_3;
+ case DP_PATTERN_TPS4:
+ return DPCD_TRAINING_PATTERN_4;
+ default:
+ drm_err(dp->dev, "dp link unknown pattern %d\n", pattern);
+ return -EINVAL;
+ }
+}
+
+static int dp_link_set_pattern(struct hibmc_dp_dev *dp, enum dp_pattern_e pattern)
+{
+ int ret;
+ u8 buf;
+
+ ret = dp_link_pattern2dpcd(dp, pattern);
+ if (ret < 0)
+ return ret;
+
+ buf = (u8)ret;
+ if (pattern != DPCD_TRAINING_PATTERN_DISABLE && pattern != DPCD_TRAINING_PATTERN_4) {
+ buf |= DPCD_SCRAMBLING_DISABLE;
+ dp_write_bits(dp->base + DP_PHYIF_CTRL0, DP_CFG_SCRAMBLE_EN, 0x1);
+ } else {
+ dp_write_bits(dp->base + DP_PHYIF_CTRL0, DP_CFG_SCRAMBLE_EN, 0);
+ }
+
+ dp_write_bits(dp->base + DP_PHYIF_CTRL0, DP_CFG_PAT_SEL, pattern);
+
+ ret = dp_aux_write(dp, DPCD_TRAINING_PATTERN_SET, &buf, sizeof(buf));
+ if (ret)
+ drm_err(dp->dev, "dp aux write training pattern set failed\n");
+
+ return ret;
+}
+
+static int dp_link_training_cr_pre(struct hibmc_dp_dev *dp)
+{
+ u8 *train_set = dp->link.train_set;
+ int ret;
+ u8 i;
+
+ ret = dp_link_training_configure(dp);
+ if (ret)
+ return ret;
+
+ ret = dp_link_set_pattern(dp, DP_PATTERN_TPS1);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < dp->link.cap.lanes; i++)
+ train_set[i] = DPCD_VOLTAGE_SWING_LEVEL_2 | DPCD_PRE_EMPHASIS_LEVEL_0;
+
+ ret = dp_aux_write(dp, DPCD_TRAINING_LANE0_SET, train_set, dp->link.cap.lanes);
+ if (ret)
+ drm_err(dp->dev, "dp aux write training lane set failed\n");
+
+ return ret;
+}
+
+static bool dp_dpcd_cr_done_check_and_update(u8 lane_status, u8 lane_count,
+ u8 *cr_done_lanes)
+{
+ bool is_ok = true;
+ u8 val;
+
+ *cr_done_lanes = GENMASK(lane_count - 1, 0);
+
+ for (u8 lane = 0; lane < lane_count; lane++) {
+ val = lane_status >> (lane * AUX_4_BIT);
+ if ((val & DPCD_CR_DONE_BITS) == 0) {
+ *cr_done_lanes &= ~(BIT(lane));
+ is_ok = false;
+ }
+ }
+
+ return is_ok;
+}
+
+static bool dp_dpcd_eq_is_ok(u8 lane_status, u8 lane_count)
+{
+ u8 val;
+
+ for (u8 lane = 0; lane < lane_count; lane++) {
+ val = (lane_status >> (lane * AUX_4_BIT));
+ if ((val & DPCD_EQ_DONE_BITS) != DPCD_EQ_DONE_BITS)
+ return false;
+ }
+
+ return true;
+}
+
+static bool dp_link_get_adjust_train(struct hibmc_dp_dev *dp, u8 lane_status)
+{
+ u8 pre_emph[DP_LANE_NUM_MAX] = {0};
+ u8 voltage[DP_LANE_NUM_MAX] = {0};
+ bool changed = false;
+ u8 train_set;
+ u8 lane;
+
+ /* not support level 3 */
+ for (lane = 0; lane < dp->link.cap.lanes; lane++) {
+ voltage[lane] = (lane_status & (DPCD_VOLTAGE_SWING_LANE_0 << (AUX_4_BIT * lane)))
+ << DPCD_VOLTAGE_SWING_SET_S;
+ pre_emph[lane] = (lane_status & (DPCD_PRE_EMPHASIS_LANE_0 << (AUX_4_BIT * lane)))
+ << DPCD_PRE_EMPHASIS_SET_S;
+ }
+
+ for (lane = 0; lane < dp->link.cap.lanes; lane++) {
+ train_set = voltage[lane] | pre_emph[lane];
+ if (dp->link.train_set[lane] != train_set) {
+ changed = true;
+ dp->link.train_set[lane] = train_set;
+ }
+ }
+
+ return changed;
+}
+
+static int dp_link_reduce_rate(struct hibmc_dp_dev *dp)
+{
+ u8 link_rate_map[DP_LINK_RATE_NUM] = {DP_LINK_RATE_0, DP_LINK_RATE_1,
+ DP_LINK_RATE_2, DP_LINK_RATE_3};
+
+ for (u8 i = 0; i < DP_LINK_RATE_NUM; i++) {
+ if (link_rate_map[i] == dp->link.cap.link_rate) {
+ if (i == 0) {
+ drm_err(dp->dev, "dp link training reduce rate failed, already lowest rate\n");
+ return -EFAULT;
+ }
+ dp->link.cap.link_rate = link_rate_map[i - 1];
+ return 0;
+ }
+ }
+
+ drm_err(dp->dev, "dp link training reduce rate failed, rate match failed\n");
+ return -EFAULT;
+}
+
+static int dp_link_reduce_lane(struct hibmc_dp_dev *dp)
+{
+ /* currently only 1 lane */
+ dp->link.cap.lanes = DP_LANE_NUM_1;
+
+ return 0;
+}
+
+static int dp_link_training_cr(struct hibmc_dp_dev *dp)
+{
+ u8 lane_status[DP_LANE_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 >= DPCD_REVISION_14 ? 10 : 80;
+
+ voltage_tries = 1;
+ for (cr_tries = 0; cr_tries < max_cr; cr_tries++) {
+ msleep(50);
+
+ ret = dp_aux_read(dp, DPCD_LANE0_1_STATUS, lane_status, DP_LANE_STATUS_SIZE);
+ if (ret) {
+ drm_err(dp->dev, "Get lane status failed\n");
+ return ret;
+ }
+
+ ret = dp_dpcd_cr_done_check_and_update(lane_status[0], dp->link.cap.lanes,
+ &dp->link.status.cr_done_lanes);
+ if (ret) {
+ 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;
+ }
+
+ ret = dp_aux_read(dp, DPCD_ADJUST_REQUEST_LANE0_1, lane_status,
+ DP_LANE_STATUS_SIZE);
+ if (ret) {
+ drm_err(dp->dev, "Get adjust status failed\n");
+ return ret;
+ }
+
+ level_changed = dp_link_get_adjust_train(dp, lane_status[0]);
+ ret = dp_aux_write(dp, DPCD_TRAINING_LANE0_SET, dp->link.train_set,
+ dp->link.cap.lanes);
+ if (ret) {
+ drm_err(dp->dev, "Update link training failed\n");
+ return 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 dp_link_training_channel_eq(struct hibmc_dp_dev *dp)
+{
+ u8 lane_status[DP_LANE_STATUS_SIZE] = {0};
+ enum dp_pattern_e tps;
+ u8 eq_tries;
+ int ret;
+
+ if (dp->link.cap.is_tps4)
+ tps = DP_PATTERN_TPS4;
+ else if (dp->link.cap.is_tps3)
+ tps = DP_PATTERN_TPS3;
+ else
+ tps = DP_PATTERN_TPS2;
+
+ ret = dp_link_set_pattern(dp, tps);
+ if (ret)
+ return ret;
+
+ for (eq_tries = 0; eq_tries < EQ_MAX_RETRY; eq_tries++) {
+ msleep(50);
+
+ ret = dp_aux_read(dp, DPCD_LANE0_1_STATUS, lane_status, DP_LANE_STATUS_SIZE);
+ if (ret) {
+ drm_err(dp->dev, "get lane status failed\n");
+ break;
+ }
+
+ ret = dp_dpcd_cr_done_check_and_update(lane_status[0], dp->link.cap.lanes,
+ &dp->link.status.cr_done_lanes);
+ if (!ret) {
+ 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;
+ }
+
+ ret = dp_dpcd_eq_is_ok(lane_status[0], dp->link.cap.lanes);
+ if (ret) {
+ dp->link.status.channel_equalized = true;
+ drm_info(dp->dev, "dp link training eq done\n");
+ break;
+ }
+
+ ret = dp_aux_read(dp, DPCD_ADJUST_REQUEST_LANE0_1,
+ lane_status, DP_LANE_STATUS_SIZE);
+ if (ret) {
+ drm_err(dp->dev, "Get adjust status failed\n");
+ return ret;
+ }
+
+ dp_link_get_adjust_train(dp, lane_status[0]);
+
+ ret = dp_aux_write(dp, DPCD_TRAINING_LANE0_SET,
+ dp->link.train_set, dp->link.cap.lanes);
+ if (ret) {
+ drm_err(dp->dev, "Update link training failed\n");
+ break;
+ }
+ }
+
+ if (eq_tries == EQ_MAX_RETRY)
+ drm_err(dp->dev, "channel equalization failed %u times\n", eq_tries);
+
+ dp_link_set_pattern(dp, DP_PATTERN_NO);
+
+ return ret;
+}
+
+static int dp_link_downgrade_training_cr(struct hibmc_dp_dev *dp)
+{
+ if (dp_link_reduce_rate(dp))
+ return dp_link_reduce_lane(dp);
+
+ return 0;
+}
+
+static int dp_link_downgrade_training_eq(struct hibmc_dp_dev *dp)
+{
+ if ((!dp->link.status.clock_recovered && dp->link.status.cr_done_lanes != 0) ||
+ (dp->link.status.clock_recovered && !dp->link.status.channel_equalized)) {
+ if (!dp_link_reduce_lane(dp))
+ return 0;
+ }
+
+ return dp_link_reduce_rate(dp);
+}
+
+int dp_link_training(struct hibmc_dp_dev *dp)
+{
+ struct hibmc_dp_link *link = &dp->link;
+ int ret;
+
+ while (true) {
+ ret = dp_link_training_cr_pre(dp);
+ if (ret)
+ goto err;
+
+ ret = dp_link_training_cr(dp);
+ if (ret)
+ goto err;
+
+ if (!link->status.clock_recovered) {
+ ret = dp_link_downgrade_training_cr(dp);
+ if (ret)
+ goto err;
+ continue;
+ }
+
+ ret = dp_link_training_channel_eq(dp);
+ if (ret)
+ goto err;
+
+ if (!link->status.channel_equalized) {
+ ret = dp_link_downgrade_training_eq(dp);
+ if (ret)
+ goto err;
+ continue;
+ }
+
+ return 0;
+ }
+
+err:
+ dp_link_set_pattern(dp, DP_PATTERN_NO);
+
+ return ret;
+}
diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.h
new file mode 100644
index 000000000000..3271cdc4550c
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (c) 2024 Hisilicon Limited. */
+
+#ifndef DP_LINK_H
+#define DP_LINK_H
+
+#include "dp_comm.h"
+
+#define DP_LANE_NUM_MAX 2
+#define DP_LANE_STATUS_SIZE 1
+#define DP_LANE_NUM_1 0x1
+#define DP_LANE_NUM_2 0x2
+
+enum dp_pattern_e {
+ DP_PATTERN_NO = 0,
+ DP_PATTERN_TPS1,
+ DP_PATTERN_TPS2,
+ DP_PATTERN_TPS3,
+ DP_PATTERN_TPS4,
+};
+
+int dp_link_training(struct hibmc_dp_dev *dp);
+
+#endif
--
2.33.0
