On Tue, 23 May 2023 at 00:31, Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx> wrote:
>
> The internal_hpd flag is set to true by dp_bridge_hpd_enable() and set to
> false by dp_bridge_hpd_disable() to handle GPIO pinmuxed into DP controller
> case. HDP related interrupts can not be enabled until internal_hpd is set
> to true. At current implementation dp_display_config_hpd() will initialize
> DP host controller first followed by enabling HDP related interrupts if
> internal_hpd was true at that time. Enable HDP related interrupts depends on
> internal_hpd status may leave system with DP driver host is in running state
> but without HDP related interrupts being enabled. This will prevent external
> display from being detected. Eliminated this dependency by moving HDP related
> interrupts enable/disable be done at dp_bridge_hpd_enable/disable() directly
> regardless of internal_hpd status.
>
> Changes in V3:
> -- dp_catalog_ctrl_hpd_enable() and dp_catalog_ctrl_hpd_disable()
> -- rewording ocmmit text
>
> Fixes: cd198caddea7 ("drm/msm/dp: Rely on hpd_enable/disable callbacks")
> Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/dp/dp_catalog.c | 15 +++++++-
> drivers/gpu/drm/msm/dp/dp_catalog.h | 3 +-
> drivers/gpu/drm/msm/dp/dp_display.c | 70 +++++++++++--------------------------
> 3 files changed, 37 insertions(+), 51 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
> index 7a8cf1c..5142aeb 100644
> --- a/drivers/gpu/drm/msm/dp/dp_catalog.c
> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
> @@ -620,7 +620,7 @@ void dp_catalog_hpd_config_intr(struct dp_catalog *dp_catalog,
> config & DP_DP_HPD_INT_MASK);
> }
>
> -void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog)
> +void dp_catalog_ctrl_hpd_enable(struct dp_catalog *dp_catalog)
> {
> struct dp_catalog_private *catalog = container_of(dp_catalog,
> struct dp_catalog_private, dp_catalog);
> @@ -635,6 +635,19 @@ void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog)
> dp_write_aux(catalog, REG_DP_DP_HPD_CTRL, DP_DP_HPD_CTRL_HPD_EN);
> }
>
> +void dp_catalog_ctrl_hpd_disable(struct dp_catalog *dp_catalog)
> +{
> + struct dp_catalog_private *catalog = container_of(dp_catalog,
> + struct dp_catalog_private, dp_catalog);
> +
> + u32 reftimer = dp_read_aux(catalog, REG_DP_DP_HPD_REFTIMER);
> +
> + reftimer &= ~DP_DP_HPD_REFTIMER_ENABLE;
> + dp_write_aux(catalog, REG_DP_DP_HPD_REFTIMER, reftimer);
> +
> + dp_write_aux(catalog, REG_DP_DP_HPD_CTRL, 0);
> +}
> +
> static void dp_catalog_enable_sdp(struct dp_catalog_private *catalog)
> {
> /* trigger sdp */
> diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
> index 82376a2..38786e8 100644
> --- a/drivers/gpu/drm/msm/dp/dp_catalog.h
> +++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
> @@ -104,7 +104,8 @@ bool dp_catalog_ctrl_mainlink_ready(struct dp_catalog *dp_catalog);
> void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog, bool enable);
> void dp_catalog_hpd_config_intr(struct dp_catalog *dp_catalog,
> u32 intr_mask, bool en);
> -void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog);
> +void dp_catalog_ctrl_hpd_enable(struct dp_catalog *dp_catalog);
> +void dp_catalog_ctrl_hpd_disable(struct dp_catalog *dp_catalog);
> void dp_catalog_ctrl_config_psr(struct dp_catalog *dp_catalog);
> void dp_catalog_ctrl_set_psr(struct dp_catalog *dp_catalog, bool enter);
> u32 dp_catalog_link_is_connected(struct dp_catalog *dp_catalog);
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 3e13acdf..69bbc5f 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -615,12 +615,6 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
> dp->hpd_state = ST_MAINLINK_READY;
> }
>
> - /* enable HDP irq_hpd/replug interrupt */
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog,
> - DP_DP_IRQ_HPD_INT_MASK | DP_DP_HPD_REPLUG_INT_MASK,
> - true);
> -
> drm_dbg_dp(dp->drm_dev, "After, type=%d hpd_state=%d\n",
> dp->dp_display.connector_type, state);
> mutex_unlock(&dp->event_mutex);
> @@ -658,12 +652,6 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
> drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
> dp->dp_display.connector_type, state);
>
> - /* disable irq_hpd/replug interrupts */
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog,
> - DP_DP_IRQ_HPD_INT_MASK | DP_DP_HPD_REPLUG_INT_MASK,
> - false);
> -
> /* unplugged, no more irq_hpd handle */
> dp_del_event(dp, EV_IRQ_HPD_INT);
>
> @@ -687,10 +675,6 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
> return 0;
> }
>
> - /* disable HPD plug interrupts */
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_PLUG_INT_MASK, false);
> -
> /*
> * We don't need separate work for disconnect as
> * connect/attention interrupts are disabled
> @@ -706,10 +690,6 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
> /* signal the disconnect event early to ensure proper teardown */
> dp_display_handle_plugged_change(&dp->dp_display, false);
>
> - /* enable HDP plug interrupt to prepare for next plugin */
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_PLUG_INT_MASK, true);
> -
> drm_dbg_dp(dp->drm_dev, "After, type=%d hpd_state=%d\n",
> dp->dp_display.connector_type, state);
>
> @@ -1082,26 +1062,6 @@ void msm_dp_snapshot(struct msm_disp_state *disp_state, struct msm_dp *dp)
> mutex_unlock(&dp_display->event_mutex);
> }
>
> -static void dp_display_config_hpd(struct dp_display_private *dp)
> -{
> -
> - dp_display_host_init(dp);
> - dp_catalog_ctrl_hpd_config(dp->catalog);
> -
> - /* Enable plug and unplug interrupts only if requested */
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog,
> - DP_DP_HPD_PLUG_INT_MASK |
> - DP_DP_HPD_UNPLUG_INT_MASK,
> - true);
> -
> - /* Enable interrupt first time
> - * we are leaving dp clocks on during disconnect
> - * and never disable interrupt
> - */
> - enable_irq(dp->irq);
> -}
> -
> void dp_display_set_psr(struct msm_dp *dp_display, bool enter)
> {
> struct dp_display_private *dp;
> @@ -1176,7 +1136,7 @@ static int hpd_event_thread(void *data)
>
> switch (todo->event_id) {
> case EV_HPD_INIT_SETUP:
> - dp_display_config_hpd(dp_priv);
> + dp_display_host_init(dp_priv);
> break;
> case EV_HPD_PLUG_INT:
> dp_hpd_plug_handle(dp_priv, todo->data);
> @@ -1394,13 +1354,8 @@ static int dp_pm_resume(struct device *dev)
> /* turn on dp ctrl/phy */
> dp_display_host_init(dp);
>
> - dp_catalog_ctrl_hpd_config(dp->catalog);
> -
> - if (dp->dp_display.internal_hpd)
> - dp_catalog_hpd_config_intr(dp->catalog,
> - DP_DP_HPD_PLUG_INT_MASK |
> - DP_DP_HPD_UNPLUG_INT_MASK,
> - true);
> + if (dp_display->is_edp)
> + dp_catalog_ctrl_hpd_enable(dp->catalog);
>
> if (dp_catalog_link_is_connected(dp->catalog)) {
> /*
> @@ -1568,7 +1523,7 @@ static int dp_display_get_next_bridge(struct msm_dp *dp)
>
> if (aux_bus && dp->is_edp) {
> dp_display_host_init(dp_priv);
> - dp_catalog_ctrl_hpd_config(dp_priv->catalog);
> + dp_catalog_ctrl_hpd_enable(dp_priv->catalog);
> dp_display_host_phy_init(dp_priv);
> enable_irq(dp_priv->irq);
>
> @@ -1801,16 +1756,33 @@ void dp_bridge_hpd_enable(struct drm_bridge *bridge)
> {
> struct msm_dp_bridge *dp_bridge = to_dp_bridge(bridge);
> struct msm_dp *dp_display = dp_bridge->dp_display;
> + struct dp_display_private *dp = container_of(dp_display, struct dp_display_private, dp_display);
> +
> + mutex_lock(&dp->event_mutex);
> + dp_catalog_ctrl_hpd_enable(dp->catalog);
> +
> + /* enable HDP interrupts */
> + dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_INT_MASK, true);
> +
> + enable_irq(dp->irq);
>
> dp_display->internal_hpd = true;
> + mutex_unlock(&dp->event_mutex);
> }
>
> void dp_bridge_hpd_disable(struct drm_bridge *bridge)
> {
> struct msm_dp_bridge *dp_bridge = to_dp_bridge(bridge);
> struct msm_dp *dp_display = dp_bridge->dp_display;
> + struct dp_display_private *dp = container_of(dp_display, struct dp_display_private, dp_display);
> +
> + mutex_lock(&dp->event_mutex);
> + /* disable HDP interrupts */
Should there be a disable_irq? Or maybe it would be simpler to keep
IRQ always enabled from the time of request_irq. There is a window
when the IRQ is enabled between request_irq and disable_irq.
> + dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_INT_MASK, false);
> + dp_catalog_ctrl_hpd_disable(dp->catalog);
>
> dp_display->internal_hpd = false;
> + mutex_unlock(&dp->event_mutex);
> }
>
> void dp_bridge_hpd_notify(struct drm_bridge *bridge,
> --
> 2.7.4
>
--
With best wishes
Dmitry
