[PATCH v4] drm/msm/dp: add support of tps4 (training pattern 4) for HBR3

From: Kuogee Hsieh
Date: Thu Jan 06 2022 - 19:57:32 EST


From: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>

Some DP sinkers prefer to use tps4 instead of tps3 during training #2.
This patch will use tps4 to perform link training #2 if sinker's DPCD
supports it.

Changes in V2:
-- replace dp_catalog_ctrl_set_pattern() with dp_catalog_ctrl_set_pattern_state_bit()

Changes in V3:
-- change state_ctrl_bits type to u32 and pattern type to u8

Changes in V4:
-- align } else if { and } else {

Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>

Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_catalog.c | 12 ++++++------
drivers/gpu/drm/msm/dp/dp_catalog.h | 2 +-
drivers/gpu/drm/msm/dp/dp_ctrl.c | 17 ++++++++++++-----
3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
index 6ae9b29..64f0b26 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.c
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
@@ -456,19 +456,19 @@ void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog,
dp_write_p0(catalog, MMSS_DP_DSC_DTO, 0x0);
}

-int dp_catalog_ctrl_set_pattern(struct dp_catalog *dp_catalog,
- u32 pattern)
+int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog,
+ u32 state_bit)
{
int bit, ret;
u32 data;
struct dp_catalog_private *catalog = container_of(dp_catalog,
struct dp_catalog_private, dp_catalog);

- bit = BIT(pattern - 1);
- DRM_DEBUG_DP("hw: bit=%d train=%d\n", bit, pattern);
+ bit = BIT(state_bit - 1);
+ DRM_DEBUG_DP("hw: bit=%d train=%d\n", bit, state_bit);
dp_catalog_ctrl_state_ctrl(dp_catalog, bit);

- bit = BIT(pattern - 1) << DP_MAINLINK_READY_LINK_TRAINING_SHIFT;
+ bit = BIT(state_bit - 1) << DP_MAINLINK_READY_LINK_TRAINING_SHIFT;

/* Poll for mainlink ready status */
ret = readx_poll_timeout(readl, catalog->io->dp_controller.link.base +
@@ -476,7 +476,7 @@ int dp_catalog_ctrl_set_pattern(struct dp_catalog *dp_catalog,
data, data & bit,
POLLING_SLEEP_US, POLLING_TIMEOUT_US);
if (ret < 0) {
- DRM_ERROR("set pattern for link_train=%d failed\n", pattern);
+ DRM_ERROR("set state_bit for link_train=%d failed\n", state_bit);
return ret;
}
return 0;
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
index 6965afa..7dea101 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.h
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
@@ -94,7 +94,7 @@ void dp_catalog_ctrl_mainlink_ctrl(struct dp_catalog *dp_catalog, bool enable);
void dp_catalog_ctrl_config_misc(struct dp_catalog *dp_catalog, u32 cc, u32 tb);
void dp_catalog_ctrl_config_msa(struct dp_catalog *dp_catalog, u32 rate,
u32 stream_rate_khz, bool fixed_nvid);
-int dp_catalog_ctrl_set_pattern(struct dp_catalog *dp_catalog, u32 pattern);
+int dp_catalog_ctrl_set_pattern_state_bit(struct dp_catalog *dp_catalog, u32 pattern);
void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
bool dp_catalog_ctrl_mainlink_ready(struct dp_catalog *dp_catalog);
void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog, bool enable);
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 39558a2..ad64ddd 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1083,7 +1083,7 @@ static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,

*training_step = DP_TRAINING_1;

- ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, DP_TRAINING_PATTERN_1);
+ ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, 1);
if (ret)
return ret;
dp_ctrl_train_pattern_set(ctrl, DP_TRAINING_PATTERN_1 |
@@ -1181,7 +1181,8 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
int *training_step)
{
int tries = 0, ret = 0;
- char pattern;
+ u8 pattern;
+ u32 state_ctrl_bit;
int const maximum_retries = 5;
u8 link_status[DP_LINK_STATUS_SIZE];

@@ -1189,12 +1190,18 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,

*training_step = DP_TRAINING_2;

- if (drm_dp_tps3_supported(ctrl->panel->dpcd))
+ if (drm_dp_tps4_supported(ctrl->panel->dpcd)) {
+ pattern = DP_TRAINING_PATTERN_4;
+ state_ctrl_bit = 4;
+ } else if (drm_dp_tps3_supported(ctrl->panel->dpcd)) {
pattern = DP_TRAINING_PATTERN_3;
- else
+ state_ctrl_bit = 3;
+ } else {
pattern = DP_TRAINING_PATTERN_2;
+ state_ctrl_bit = 2;
+ }

- ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, pattern);
+ ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, state_ctrl_bit);
if (ret)
return ret;

--
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