[PATCH v2 0/3] drm/msm/dp: More cleanups for force link train

[PATCH v2 0/3] drm/msm/dp: More cleanups for force link train

[Stephen Boyd]

These patches do a little cleanup on the v9 patch[1] from Kuogee.

Changes from v1:
 * Reduce code even more in second patch
 * Pick up tags on first patch

Stephen Boyd (3):
  drm/msm/dp: Reorganize code to avoid forward declaration
  drm/msm/dp: Remove pixel_rate from struct dp_ctrl
  drm/msm/dp: Get rid of dp_ctrl_on_stream_phy_test_report()

 drivers/gpu/drm/msm/dp/dp_ctrl.c | 148 ++++++++++++-------------------
 drivers/gpu/drm/msm/dp/dp_ctrl.h |   1 -
 2 files changed, 59 insertions(+), 90 deletions(-)

[1] https://lore.kernel.org/r/1655411200-7255-1-git-send-email-quic_khsieh@quicinc.com

base-commit: f2906aa863381afb0015a9eb7fefad885d4e5a56
prerequisite-patch-id: 2fc33a2830ec84d922023fddb585728c48a59525
-- 
https://chromeos.dev

[PATCH v2 1/3] drm/msm/dp: Reorganize code to avoid forward declaration

[Stephen Boyd]

Let's move these functions around to avoid having to forward declare
dp_ctrl_on_stream_phy_test_report(). Also remove
dp_ctrl_reinitialize_mainlink() forward declaration because we're doing
that sort of task.

Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 drivers/gpu/drm/msm/dp/dp_ctrl.c | 104 +++++++++++++++----------------
 1 file changed, 50 insertions(+), 54 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 703249384e7c..bd445e683cfc 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1238,8 +1238,6 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
 	return -ETIMEDOUT;
 }
 
-static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl);
-
 static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl,
 			int *training_step)
 {
@@ -1534,38 +1532,6 @@ static int dp_ctrl_link_maintenance(struct dp_ctrl_private *ctrl)
 	return ret;
 }
 
-static int dp_ctrl_on_stream_phy_test_report(struct dp_ctrl *dp_ctrl);
-
-static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
-{
-	int ret = 0;
-
-	if (!ctrl->link->phy_params.phy_test_pattern_sel) {
-		drm_dbg_dp(ctrl->drm_dev,
-			"no test pattern selected by sink\n");
-		return ret;
-	}
-
-	/*
-	 * The global reset will need DP link related clocks to be
-	 * running. Add the global reset just before disabling the
-	 * link clocks and core clocks.
-	 */
-	ret = dp_ctrl_off(&ctrl->dp_ctrl);
-	if (ret) {
-		DRM_ERROR("failed to disable DP controller\n");
-		return ret;
-	}
-
-	ret = dp_ctrl_on_link(&ctrl->dp_ctrl);
-	if (!ret)
-		ret = dp_ctrl_on_stream_phy_test_report(&ctrl->dp_ctrl);
-	else
-		DRM_ERROR("failed to enable DP link controller\n");
-
-	return ret;
-}
-
 static bool dp_ctrl_send_phy_test_pattern(struct dp_ctrl_private *ctrl)
 {
 	bool success = false;
@@ -1618,6 +1584,56 @@ static bool dp_ctrl_send_phy_test_pattern(struct dp_ctrl_private *ctrl)
 	return success;
 }
 
+static int dp_ctrl_on_stream_phy_test_report(struct dp_ctrl *dp_ctrl)
+{
+	int ret;
+	struct dp_ctrl_private *ctrl;
+
+	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
+
+	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
+
+	ret = dp_ctrl_enable_stream_clocks(ctrl);
+	if (ret) {
+		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
+		return ret;
+	}
+
+	dp_ctrl_send_phy_test_pattern(ctrl);
+
+	return 0;
+}
+
+static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
+{
+	int ret = 0;
+
+	if (!ctrl->link->phy_params.phy_test_pattern_sel) {
+		drm_dbg_dp(ctrl->drm_dev,
+			"no test pattern selected by sink\n");
+		return ret;
+	}
+
+	/*
+	 * The global reset will need DP link related clocks to be
+	 * running. Add the global reset just before disabling the
+	 * link clocks and core clocks.
+	 */
+	ret = dp_ctrl_off(&ctrl->dp_ctrl);
+	if (ret) {
+		DRM_ERROR("failed to disable DP controller\n");
+		return ret;
+	}
+
+	ret = dp_ctrl_on_link(&ctrl->dp_ctrl);
+	if (!ret)
+		ret = dp_ctrl_on_stream_phy_test_report(&ctrl->dp_ctrl);
+	else
+		DRM_ERROR("failed to enable DP link controller\n");
+
+	return ret;
+}
+
 void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl)
 {
 	struct dp_ctrl_private *ctrl;
@@ -1815,26 +1831,6 @@ static int dp_ctrl_link_retrain(struct dp_ctrl_private *ctrl)
 	return dp_ctrl_setup_main_link(ctrl, &training_step);
 }
 
-static int dp_ctrl_on_stream_phy_test_report(struct dp_ctrl *dp_ctrl)
-{
-	int ret;
-	struct dp_ctrl_private *ctrl;
-
-	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
-
-	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
-
-	ret = dp_ctrl_enable_stream_clocks(ctrl);
-	if (ret) {
-		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
-		return ret;
-	}
-
-	dp_ctrl_send_phy_test_pattern(ctrl);
-
-	return 0;
-}
-
 int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 {
 	int ret = 0;
-- 
https://chromeos.dev

[PATCH v2 2/3] drm/msm/dp: Remove pixel_rate from struct dp_ctrl

[Stephen Boyd]

This struct member is stored to in the function that calls the function
which uses it. That's possible with a function argument instead of
storing to a struct member. Pass the pixel_rate as an argument instead
to simplify the code. Note that dp_ctrl_link_maintenance() was storing
the pixel_rate but never using it so we just remove the assignment from
there.

Cc: Kuogee Hsieh <quic_khsieh@quicinc.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---

dp_ctrl_on_link() almost doesn't even use the pixel_clk either. It just
prints the value. I kept it around because maybe it is useful? But if
not, then we can remove even more code.

 drivers/gpu/drm/msm/dp/dp_ctrl.c | 60 ++++++++++++--------------------
 drivers/gpu/drm/msm/dp/dp_ctrl.h |  1 -
 2 files changed, 22 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index bd445e683cfc..feb26d4d6e97 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1357,25 +1357,7 @@ static int dp_ctrl_enable_mainlink_clocks(struct dp_ctrl_private *ctrl)
 	if (ret)
 		DRM_ERROR("Unable to start link clocks. ret=%d\n", ret);
 
-	drm_dbg_dp(ctrl->drm_dev, "link rate=%d pixel_clk=%d\n",
-		ctrl->link->link_params.rate, ctrl->dp_ctrl.pixel_rate);
-
-	return ret;
-}
-
-static int dp_ctrl_enable_stream_clocks(struct dp_ctrl_private *ctrl)
-{
-	int ret = 0;
-
-	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel",
-					ctrl->dp_ctrl.pixel_rate * 1000);
-
-	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
-	if (ret)
-		DRM_ERROR("Unabled to start pixel clocks. ret=%d\n", ret);
-
-	drm_dbg_dp(ctrl->drm_dev, "link rate=%d pixel_clk=%d\n",
-			ctrl->link->link_params.rate, ctrl->dp_ctrl.pixel_rate);
+	drm_dbg_dp(ctrl->drm_dev, "link rate=%d\n", ctrl->link->link_params.rate);
 
 	return ret;
 }
@@ -1517,8 +1499,6 @@ static int dp_ctrl_link_maintenance(struct dp_ctrl_private *ctrl)
 	ctrl->link->phy_params.p_level = 0;
 	ctrl->link->phy_params.v_level = 0;
 
-	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
-
 	ret = dp_ctrl_setup_main_link(ctrl, &training_step);
 	if (ret)
 		goto end;
@@ -1588,14 +1568,16 @@ static int dp_ctrl_on_stream_phy_test_report(struct dp_ctrl *dp_ctrl)
 {
 	int ret;
 	struct dp_ctrl_private *ctrl;
+	unsigned long pixel_rate;
 
 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
 
-	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
+	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
+	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
 
-	ret = dp_ctrl_enable_stream_clocks(ctrl);
+	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
 	if (ret) {
-		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
+		DRM_ERROR("Unable to start pixel clocks. ret=%d\n", ret);
 		return ret;
 	}
 
@@ -1704,11 +1686,12 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 {
 	int rc = 0;
 	struct dp_ctrl_private *ctrl;
-	u32 rate = 0;
+	u32 rate;
 	int link_train_max_retries = 5;
 	u32 const phy_cts_pixel_clk_khz = 148500;
 	u8 link_status[DP_LINK_STATUS_SIZE];
 	unsigned int training_step;
+	unsigned long pixel_rate;
 
 	if (!dp_ctrl)
 		return -EINVAL;
@@ -1716,25 +1699,24 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
 
 	rate = ctrl->panel->link_info.rate;
+	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
 
 	dp_power_clk_enable(ctrl->power, DP_CORE_PM, true);
 
 	if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN) {
 		drm_dbg_dp(ctrl->drm_dev,
 				"using phy test link parameters\n");
-		if (!ctrl->panel->dp_mode.drm_mode.clock)
-			ctrl->dp_ctrl.pixel_rate = phy_cts_pixel_clk_khz;
+		if (!pixel_rate)
+			pixel_rate = phy_cts_pixel_clk_khz;
 	} else {
 		ctrl->link->link_params.rate = rate;
 		ctrl->link->link_params.num_lanes =
 			ctrl->panel->link_info.num_lanes;
-		ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
 	}
 
-	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%d\n",
+	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
 		ctrl->link->link_params.rate, ctrl->link->link_params.num_lanes,
-		ctrl->dp_ctrl.pixel_rate);
-
+		pixel_rate);
 
 	rc = dp_ctrl_enable_mainlink_clocks(ctrl);
 	if (rc)
@@ -1836,6 +1818,7 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 	int ret = 0;
 	bool mainlink_ready = false;
 	struct dp_ctrl_private *ctrl;
+	unsigned long pixel_rate;
 	unsigned long pixel_rate_orig;
 
 	if (!dp_ctrl)
@@ -1843,15 +1826,14 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 
 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
 
-	ctrl->dp_ctrl.pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
+	pixel_rate = pixel_rate_orig = ctrl->panel->dp_mode.drm_mode.clock;
 
-	pixel_rate_orig = ctrl->dp_ctrl.pixel_rate;
 	if (dp_ctrl->wide_bus_en)
-		ctrl->dp_ctrl.pixel_rate >>= 1;
+		pixel_rate >>= 1;
 
-	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%d\n",
+	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
 		ctrl->link->link_params.rate,
-		ctrl->link->link_params.num_lanes, ctrl->dp_ctrl.pixel_rate);
+		ctrl->link->link_params.num_lanes, pixel_rate);
 
 	if (!dp_power_clk_status(ctrl->power, DP_CTRL_PM)) { /* link clk is off */
 		ret = dp_ctrl_enable_mainlink_clocks(ctrl);
@@ -1861,9 +1843,11 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 		}
 	}
 
-	ret = dp_ctrl_enable_stream_clocks(ctrl);
+	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
+
+	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
 	if (ret) {
-		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
+		DRM_ERROR("Unable to start pixel clocks. ret=%d\n", ret);
 		goto end;
 	}
 
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp_ctrl.h
index b563e2e3bfe5..9f29734af81c 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
@@ -16,7 +16,6 @@
 struct dp_ctrl {
 	bool orientation;
 	atomic_t aborted;
-	u32 pixel_rate;
 	bool wide_bus_en;
 };
 
-- 
https://chromeos.dev

Re: [PATCH v2 2/3] drm/msm/dp: Remove pixel_rate from struct dp_ctrl

[Dmitry Baryshkov]

On 23/06/2022 03:25, Stephen Boyd wrote:
> This struct member is stored to in the function that calls the function
> which uses it. That's possible with a function argument instead of
> storing to a struct member. Pass the pixel_rate as an argument instead
> to simplify the code. Note that dp_ctrl_link_maintenance() was storing
> the pixel_rate but never using it so we just remove the assignment from
> there.
> 
> Cc: Kuogee Hsieh <quic_khsieh@quicinc.com>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>


> ---
> 
> dp_ctrl_on_link() almost doesn't even use the pixel_clk either. It just
> prints the value. I kept it around because maybe it is useful? But if
> not, then we can remove even more code.

Feel free to submit a patch and check if anybody (Kuogee? Abhinav?) 
complains.

-- 
With best wishes
Dmitry

[PATCH v2 3/3] drm/msm/dp: Get rid of dp_ctrl_on_stream_phy_test_report()

[Stephen Boyd]

This API isn't really more than a couple lines now that we don't store
the pixel_rate to the struct member. Inline it into the caller.

Cc: Kuogee Hsieh <quic_khsieh@quicinc.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 drivers/gpu/drm/msm/dp/dp_ctrl.c | 44 ++++++++++++--------------------
 1 file changed, 17 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index feb26d4d6e97..e475f4ca078a 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1564,36 +1564,15 @@ static bool dp_ctrl_send_phy_test_pattern(struct dp_ctrl_private *ctrl)
 	return success;
 }
 
-static int dp_ctrl_on_stream_phy_test_report(struct dp_ctrl *dp_ctrl)
+static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
 {
 	int ret;
-	struct dp_ctrl_private *ctrl;
 	unsigned long pixel_rate;
 
-	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
-
-	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
-	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
-
-	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
-	if (ret) {
-		DRM_ERROR("Unable to start pixel clocks. ret=%d\n", ret);
-		return ret;
-	}
-
-	dp_ctrl_send_phy_test_pattern(ctrl);
-
-	return 0;
-}
-
-static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
-{
-	int ret = 0;
-
 	if (!ctrl->link->phy_params.phy_test_pattern_sel) {
 		drm_dbg_dp(ctrl->drm_dev,
 			"no test pattern selected by sink\n");
-		return ret;
+		return 0;
 	}
 
 	/*
@@ -1608,12 +1587,23 @@ static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
 	}
 
 	ret = dp_ctrl_on_link(&ctrl->dp_ctrl);
-	if (!ret)
-		ret = dp_ctrl_on_stream_phy_test_report(&ctrl->dp_ctrl);
-	else
+	if (ret) {
 		DRM_ERROR("failed to enable DP link controller\n");
+		return ret;
+	}
 
-	return ret;
+	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
+	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
+
+	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
+	if (ret) {
+		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
+		return ret;
+	}
+
+	dp_ctrl_send_phy_test_pattern(ctrl);
+
+	return 0;
 }
 
 void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl)
-- 
https://chromeos.dev

Re: [PATCH v2 3/3] drm/msm/dp: Get rid of dp_ctrl_on_stream_phy_test_report()

[Dmitry Baryshkov]

On 23/06/2022 03:25, Stephen Boyd wrote:
> This API isn't really more than a couple lines now that we don't store
> the pixel_rate to the struct member. Inline it into the caller.
> 
> Cc: Kuogee Hsieh <quic_khsieh@quicinc.com>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

> ---
>   drivers/gpu/drm/msm/dp/dp_ctrl.c | 44 ++++++++++++--------------------
>   1 file changed, 17 insertions(+), 27 deletions(-)
> 

-- 
With best wishes
Dmitry