Re: [PATCH v3] drm/msm/dp: do not initialize phy until plugin interrupt received

On 11/8/2021 4:29 PM, Bjorn Andersson wrote:

On Mon 08 Nov 15:42 PST 2021, Kuogee Hsieh wrote:

...

From: Kuogee Hsieh khsieh@codeaurora.org

Combo phy supports both USB and DP simultaneously. There may has a possible conflict during phy initialization phase between USB and DP driver which may cause USB phy timeout when USB tries to power up its phy. This patch has the DP driver not initialize its phy during DP driver initialization phase. Instead DP driver only enable required regulators and clocks so that it is able to receive HPD interrupts after completion of initialization phase. DP driver will initialize its phy when HPD plug-in interrupt received. This patch also provides a positive side effects which balance regulator enable count since regulator only enabled at initialize phase and resume and disabled at followed suspend.

I thought you said that you (someone) will attempt to resolve the described error in the QMP driver, making this patch unnecessary.

That said, are there any other benefits to this patch? I.e. does it make sense not to initialize the phy when there's no cable connected for power purposed etc? If so this patch looks reasonable in itself, but the commit message is wrong.

Thanks, Bjorn

sorry for the confusing.

I will redo the commit test.

Thanks,

...

Changes in V2: -- removed unnecessary dp_ctrl NULL check -- removed unnecessary phy init_count and power_count DRM_DEBUG_DP logs -- remove flip parameter out of dp_ctrl_irq_enable() -- add fixes tag

Changes in V3: -- call dp_display_host_phy_init() instead of dp_ctrl_phy_init() at dp_display_host_init() for eDP

Fixes: e91e3065a806 ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets")

Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com

drivers/gpu/drm/msm/dp/dp_ctrl.c | 87 ++++++++++++++++--------------------- drivers/gpu/drm/msm/dp/dp_ctrl.h | 9 ++-- drivers/gpu/drm/msm/dp/dp_display.c | 83 ++++++++++++++++++++++++++--------- 3 files changed, 105 insertions(+), 74 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 7ec155d..4788e8c 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1364,60 +1364,54 @@ static int dp_ctrl_enable_stream_clocks(struct dp_ctrl_private *ctrl) return ret; }

-int dp_ctrl_host_init(struct dp_ctrl *dp_ctrl, bool flip, bool reset) +void dp_ctrl_irq_enable(struct dp_ctrl *dp_ctrl) +{

• struct dp_ctrl_private *ctrl;
• ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
• dp_catalog_ctrl_reset(ctrl->catalog);
• dp_catalog_ctrl_enable_irq(ctrl->catalog, true);

+}

+void dp_ctrl_irq_disable(struct dp_ctrl *dp_ctrl) +{

• struct dp_ctrl_private *ctrl;
• ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
• dp_catalog_ctrl_reset(ctrl->catalog);
• dp_catalog_ctrl_enable_irq(ctrl->catalog, false);

+}

+void dp_ctrl_phy_init(struct dp_ctrl *dp_ctrl) { struct dp_ctrl_private *ctrl; struct dp_io *dp_io; struct phy *phy;

• if (!dp_ctrl) {

• DRM_ERROR("Invalid input data\n");
  

• return -EINVAL;
  

• }

• ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl); dp_io = &ctrl->parser->io; phy = dp_io->phy;

• ctrl->dp_ctrl.orientation = flip;

• if (reset)

• dp_catalog_ctrl_reset(ctrl->catalog);
  

• DRM_DEBUG_DP("flip=%d\n", flip); dp_catalog_ctrl_phy_reset(ctrl->catalog); phy_init(phy);

• dp_catalog_ctrl_enable_irq(ctrl->catalog, true);

• return 0; }

-/**

• • dp_ctrl_host_deinit() - Uninitialize DP controller
• • @dp_ctrl: Display Port Driver data
• • Perform required steps to uninitialize DP controller
• • and its resources.
• */

-void dp_ctrl_host_deinit(struct dp_ctrl *dp_ctrl) +void dp_ctrl_phy_exit(struct dp_ctrl *dp_ctrl) { struct dp_ctrl_private *ctrl; struct dp_io *dp_io; struct phy *phy;

• if (!dp_ctrl) {

• DRM_ERROR("Invalid input data\n");
  

• return;
  

• }

• ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl); dp_io = &ctrl->parser->io; phy = dp_io->phy;

• dp_catalog_ctrl_enable_irq(ctrl->catalog, false);

• dp_catalog_ctrl_phy_reset(ctrl->catalog); phy_exit(phy);

• DRM_DEBUG_DP("Host deinitialized successfully\n"); }

  static bool dp_ctrl_use_fixed_nvid(struct dp_ctrl_private *ctrl)

@@ -1895,8 +1889,14 @@ int dp_ctrl_off_link_stream(struct dp_ctrl *dp_ctrl) return ret; }

• DRM_DEBUG_DP("Before, phy=%x init_count=%d power_on=%d\n",

• (u32)(uintptr_t)phy, phy->init_count, phy->power_count);
  

• phy_power_off(phy);

• DRM_DEBUG_DP("After, phy=%x init_count=%d power_on=%d\n",

• (u32)(uintptr_t)phy, phy->init_count, phy->power_count);
  

• /* aux channel down, reinit phy */ phy_exit(phy); phy_init(phy);

@@ -1905,23 +1905,6 @@ int dp_ctrl_off_link_stream(struct dp_ctrl *dp_ctrl) return ret; }

-void dp_ctrl_off_phy(struct dp_ctrl *dp_ctrl) -{

• struct dp_ctrl_private *ctrl;
• struct dp_io *dp_io;
• struct phy *phy;
• ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
• dp_io = &ctrl->parser->io;
• phy = dp_io->phy;
• dp_catalog_ctrl_reset(ctrl->catalog);
• phy_exit(phy);
• DRM_DEBUG_DP("DP off phy done\n");

-}

• int dp_ctrl_off(struct dp_ctrl *dp_ctrl) { struct dp_ctrl_private *ctrl;

@@ -1949,10 +1932,14 @@ int dp_ctrl_off(struct dp_ctrl *dp_ctrl) DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret); }

• DRM_DEBUG_DP("Before, phy=%x init_count=%d power_on=%d\n",

• (u32)(uintptr_t)phy, phy->init_count, phy->power_count);
  

• phy_power_off(phy);

• phy_exit(phy);

• DRM_DEBUG_DP("DP off done\n");

• DRM_DEBUG_DP("After, phy=%x init_count=%d power_on=%d\n",

• (u32)(uintptr_t)phy, phy->init_count, phy->power_count);
  

• return ret; }

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp_ctrl.h index 2363a2d..30f9414 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.h +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h @@ -19,12 +19,9 @@ struct dp_ctrl { u32 pixel_rate; };

-int dp_ctrl_host_init(struct dp_ctrl *dp_ctrl, bool flip, bool reset); -void dp_ctrl_host_deinit(struct dp_ctrl *dp_ctrl); int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl); int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl); int dp_ctrl_off_link_stream(struct dp_ctrl *dp_ctrl); -void dp_ctrl_off_phy(struct dp_ctrl *dp_ctrl); int dp_ctrl_off(struct dp_ctrl *dp_ctrl); void dp_ctrl_push_idle(struct dp_ctrl *dp_ctrl); void dp_ctrl_isr(struct dp_ctrl *dp_ctrl); @@ -34,4 +31,10 @@ struct dp_ctrl *dp_ctrl_get(struct device *dev, struct dp_link *link, struct dp_power *power, struct dp_catalog *catalog, struct dp_parser *parser);

+void dp_ctrl_irq_enable(struct dp_ctrl *dp_ctrl); +void dp_ctrl_irq_disable(struct dp_ctrl *dp_ctrl); +void dp_ctrl_phy_init(struct dp_ctrl *dp_ctrl); +void dp_ctrl_phy_exit(struct dp_ctrl *dp_ctrl); +void dp_ctrl_irq_phy_exit(struct dp_ctrl *dp_ctrl);

• #endif /* _DP_CTRL_H_ */

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index e41dd40..2f113ff 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -84,6 +84,7 @@ struct dp_display_private {

/* state variables */ bool core_initialized;

• bool phy_initialized; bool hpd_irq_on; bool audio_supported;

@@ -387,7 +388,29 @@ static int dp_display_process_hpd_high(struct dp_display_private *dp) return rc; }

-static void dp_display_host_init(struct dp_display_private *dp, int reset) +static void dp_display_host_phy_init(struct dp_display_private *dp) +{

• DRM_DEBUG_DP("core_init=%d phy_init=%d\n",

• 	dp->core_initialized, dp->phy_initialized);
  

• if (!dp->phy_initialized) {

• dp_ctrl_phy_init(dp->ctrl);
  

• dp->phy_initialized = true;
  

• }

+}

+static void dp_display_host_phy_exit(struct dp_display_private *dp) +{

• DRM_DEBUG_DP("core_init=%d phy_init=%d\n",

• 	dp->core_initialized, dp->phy_initialized);
  

• if (dp->phy_initialized) {

• dp_ctrl_phy_exit(dp->ctrl);
  

• dp->phy_initialized = false;
  

• }

+}

+static void dp_display_host_init(struct dp_display_private *dp) { bool flip = false;

@@ -400,8 +423,16 @@ static void dp_display_host_init(struct dp_display_private *dp, int reset) if (dp->usbpd->orientation == ORIENTATION_CC2) flip = true;

• dp_power_init(dp->power, flip);
• dp_ctrl_host_init(dp->ctrl, flip, reset);

• dp_power_init(dp->power, false);
• dp_ctrl_irq_enable(dp->ctrl);
• /*

• * eDP is the embedded primary display and has its own phy
  

• * initialize phy immediately
  

• */
  

• if (dp->dp_display.connector_type == DRM_MODE_CONNECTOR_eDP)

• dp_display_host_phy_init(dp);
  

• dp_aux_init(dp->aux); dp->core_initialized = true; }

@@ -413,7 +444,7 @@ static void dp_display_host_deinit(struct dp_display_private *dp) return; }

• dp_ctrl_host_deinit(dp->ctrl);

• dp_ctrl_irq_disable(dp->ctrl); dp_aux_deinit(dp->aux); dp_power_deinit(dp->power);

@@ -424,7 +455,7 @@ static int dp_display_usbpd_configure_cb(struct device *dev) { struct dp_display_private *dp = dev_get_dp_display_private(dev);

• dp_display_host_init(dp, true);

• dp_display_host_phy_init(dp);

  return dp_display_process_hpd_high(dp); }

@@ -551,7 +582,7 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data) dp->hpd_state = ST_DISCONNECTED;

if (ret == -ECONNRESET) { /* cable unplugged */

• 	dp->core_initialized = false;
  

• 	dp->phy_initialized = false;
  

  }

  } else {

@@ -623,9 +654,8 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data) if (state == ST_DISCONNECTED) { /* triggered by irq_hdp with sink_count = 0 */ if (dp->link->sink_count == 0) {

• 	dp_ctrl_off_phy(dp->ctrl);
  

• 	dp_display_host_phy_exit(dp);
  hpd->hpd_high = 0;
  

• 	dp->core_initialized = false;
  

  } mutex_unlock(&dp->event_mutex); return 0;

@@ -716,7 +746,7 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data)

ret = dp_display_usbpd_attention_cb(&dp->pdev->dev); if (ret == -ECONNRESET) { /* cable unplugged */

• dp->core_initialized = false;
  

• dp->phy_initialized = false;
  

  } DRM_DEBUG_DP("hpd_state=%d\n", state);

@@ -918,12 +948,19 @@ static int dp_display_disable(struct dp_display_private *dp, u32 data)

dp_display->audio_enabled = false;

• /* triggered by irq_hpd with sink_count = 0 */ if (dp->link->sink_count == 0) {

• /*
  

•  * irq_hpd with sink_count = 0
  

•  * hdmi unplugged out of dongle
  

•  */
  

  dp_ctrl_off_link_stream(dp->ctrl); } else {

• /*
  

•  * unplugged interrupt
  

•  * dongle unplugged out of DUT
  

•  */
  

  dp_ctrl_off(dp->ctrl);

• dp->core_initialized = false;
  

• dp_display_host_phy_exit(dp);
  

  }

  dp_power_panel_on(dp->power, false);

@@ -1059,7 +1096,7 @@ void msm_dp_snapshot(struct msm_disp_state *disp_state, struct msm_dp *dp) static void dp_display_config_hpd(struct dp_display_private *dp) {

• dp_display_host_init(dp, true);

• dp_display_host_init(dp); dp_catalog_ctrl_hpd_config(dp->catalog);

  /* Enable interrupt first time

@@ -1338,20 +1375,22 @@ static int dp_pm_resume(struct device *dev) dp->hpd_state = ST_DISCONNECTED;

/* turn on dp ctrl/phy */

• dp_display_host_init(dp, true);

• dp_display_host_init(dp);

  dp_catalog_ctrl_hpd_config(dp->catalog);

• /*

• * set sink to normal operation mode -- D0
  

• * before dpcd read
  

• */
  

• dp_link_psm_config(dp->link, &dp->panel->link_info, false);
• if (dp_catalog_link_is_connected(dp->catalog)) {

• /*
  

•  * set sink to normal operation mode -- D0
  

•  * before dpcd read
  

•  */
  

• dp_display_host_phy_init(dp);
  

• dp_link_psm_config(dp->link, &dp->panel->link_info, false);
  

  sink_count = drm_dp_read_sink_count(dp->aux); if (sink_count < 0) sink_count = 0;

• dp_display_host_phy_exit(dp);
  

  }

  dp->link->sink_count = sink_count;

@@ -1399,6 +1438,8 @@ static int dp_pm_suspend(struct device *dev) dp_display_host_deinit(dp); }

• dp_display_host_phy_exit(dp);

• dp->hpd_state = ST_SUSPENDED;

  /* host_init will be called at pm_resume */

@@ -1473,7 +1514,7 @@ void msm_dp_irq_postinstall(struct msm_dp *dp_display) enable_irq(dp->irq); dp_hpd_connect(dp->usbpd, true); } else {

• dp_add_event(dp, EV_HPD_INIT_SETUP, 0, dp->id * 10);
  

• dp_add_event(dp, EV_HPD_INIT_SETUP, 0, 0);
  

  } }

@@ -1567,7 +1608,7 @@ int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder) state = dp_display->hpd_state;

if (state == ST_DISPLAY_OFF)

• dp_display_host_init(dp_display, true);
  

• dp_display_host_phy_init(dp_display);
  
  

  dp_display_enable(dp_display, 0);

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