[Intel-gfx] [PATCH v4 18/23] drm/i915/display: Introduce new intel_psr_pause/resume function

[Souza, Jose]

On Fri, 2021-05-14 at 20:10 -0700, Matt Roper wrote:
> From: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
> 
> This introduces the following function that can enable and disable psr
> without intel_crtc_state/drm_connector_state when intel_psr is already
> enabled with current intel_crtc_state and drm_connector_state information.
> 
> - intel_psr_pause(): Pause current PSR. it deactivates current psr state.
> - intel_psr_resume(): Resume paused PSR without intel_crtc_state and
>                       drm_connector_state. It activates paused psr state.
> 
> Cc: José Roberto de Souza <jose.souza at intel.com>
> Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
> Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
> ---
>  .../drm/i915/display/intel_display_types.h    |  1 +
>  drivers/gpu/drm/i915/display/intel_psr.c      | 93 ++++++++++++++++---
>  drivers/gpu/drm/i915/display/intel_psr.h      |  2 +
>  3 files changed, 82 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index b8d1f702d808..ee7cbdd7db87 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1482,6 +1482,7 @@ struct intel_psr {
>  	bool sink_support;
>  	bool source_support;
>  	bool enabled;
> +	bool paused;
>  	enum pipe pipe;
>  	enum transcoder transcoder;
>  	bool active;
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index 4a63d10876ce..d4df3f5e7918 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -1060,34 +1060,23 @@ static bool psr_interrupt_error_check(struct intel_dp *intel_dp)
>  	return true;
>  }
>  
> -static void intel_psr_enable_locked(struct intel_dp *intel_dp,
> -				    const struct intel_crtc_state *crtc_state,
> -				    const struct drm_connector_state *conn_state)
> +static void _intel_psr_enable_locked(struct intel_dp *intel_dp,
> +				     const struct intel_crtc_state *crtc_state)
>  {
>  	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
>  	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
>  	struct intel_encoder *encoder = &dig_port->base;
> -	u32 val;
>  
>  	drm_WARN_ON(&dev_priv->drm, intel_dp->psr.enabled);
>  
> -	intel_dp->psr.psr2_enabled = crtc_state->has_psr2;
>  	intel_dp->psr.busy_frontbuffer_bits = 0;
> -	intel_dp->psr.pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> -	intel_dp->psr.transcoder = crtc_state->cpu_transcoder;
> -	/* DC5/DC6 requires at least 6 idle frames */
> -	val = usecs_to_jiffies(intel_get_frame_time_us(crtc_state) * 6);
> -	intel_dp->psr.dc3co_exit_delay = val;
> -	intel_dp->psr.dc3co_exitline = crtc_state->dc3co_exitline;
> -	intel_dp->psr.psr2_sel_fetch_enabled = crtc_state->enable_psr2_sel_fetch;
>  
>  	if (!psr_interrupt_error_check(intel_dp))
>  		return;
>  
>  	drm_dbg_kms(&dev_priv->drm, "Enabling PSR%s\n",
>  		    intel_dp->psr.psr2_enabled ? "2" : "1");
> -	intel_dp_compute_psr_vsc_sdp(intel_dp, crtc_state, conn_state,
> -				     &intel_dp->psr.vsc);
> +
>  	intel_write_dp_vsc_sdp(encoder, crtc_state, &intel_dp->psr.vsc);
>  	intel_psr_enable_sink(intel_dp);
>  	intel_psr_enable_source(intel_dp);
> @@ -1096,6 +1085,28 @@ static void intel_psr_enable_locked(struct intel_dp *intel_dp,
>  	intel_psr_activate(intel_dp);
>  }
>  
> +static void intel_psr_enable_locked(struct intel_dp *intel_dp,
> +				    const struct intel_crtc_state *crtc_state,
> +				    const struct drm_connector_state *conn_state)
> +{
> +	u32 val;
> +
> +	intel_dp->psr.psr2_enabled = crtc_state->has_psr2;
> +	intel_dp->psr.pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> +	intel_dp->psr.transcoder = crtc_state->cpu_transcoder;
> +	/* DC5/DC6 requires at least 6 idle frames */
> +	val = usecs_to_jiffies(intel_get_frame_time_us(crtc_state) * 6);
> +	intel_dp->psr.dc3co_exit_delay = val;
> +	intel_dp->psr.psr2_sel_fetch_enabled = crtc_state->enable_psr2_sel_fetch;
> +	intel_dp->psr.dc3co_exitline = crtc_state->dc3co_exitline;
> +	intel_dp->psr.paused = false;
> +
> +	intel_dp_compute_psr_vsc_sdp(intel_dp, crtc_state, conn_state,
> +				     &intel_dp->psr.vsc);
> +
> +	_intel_psr_enable_locked(intel_dp, crtc_state);
> +}
> +
>  /**
>   * intel_psr_enable - Enable PSR
>   * @intel_dp: Intel DP
> @@ -1233,6 +1244,60 @@ void intel_psr_disable(struct intel_dp *intel_dp,
>  	cancel_delayed_work_sync(&intel_dp->psr.dc3co_work);
>  }
>  
> +/**
> + * intel_psr_pause - Pause PSR
> + * @intel_dp: Intel DP
> + *
> + * This function need to be called after enabling psr.
> + */
> +void intel_psr_pause(struct intel_dp *intel_dp)
> +{
> +	struct intel_psr *psr = &intel_dp->psr;
> +
> +	if (!CAN_PSR(intel_dp))
> +		return;
> +
> +	mutex_lock(&psr->lock);
> +
> +	if (!psr->active) {
> +		mutex_unlock(&psr->lock);
> +		return;
> +	}
> +
> +	intel_psr_exit(intel_dp);
> +	psr->paused = true;
> +
> +	mutex_unlock(&psr->lock);
> +
> +	cancel_work_sync(&psr->work);
> +	cancel_delayed_work_sync(&psr->dc3co_work);
> +}
> +
> +/**
> + * intel_psr_resume - Resume PSR
> + * @intel_dp: Intel DP
> + *
> + * This function need to be called after pausing psr.
> + */
> +void intel_psr_resume(struct intel_dp *intel_dp)
> +{
> +	struct intel_psr *psr = &intel_dp->psr;
> +
> +	if (!CAN_PSR(intel_dp))
> +		return;
> +
> +	mutex_lock(&psr->lock);
> +
> +	if (!psr->paused)
> +		goto unlock;
> +
> +	psr->paused = false;
> +	intel_psr_activate(intel_dp);

This patch is doing a bunch of changes around the intel_psr_enable but then it is calling intel_psr_activate().

> +
> +unlock:
> +	mutex_unlock(&psr->lock);
> +}
> +
>  static void psr_force_hw_tracking_exit(struct intel_dp *intel_dp)
>  {
>  	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.h b/drivers/gpu/drm/i915/display/intel_psr.h
> index e3db85e97f4c..641521b101c8 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.h
> +++ b/drivers/gpu/drm/i915/display/intel_psr.h
> @@ -51,5 +51,7 @@ void intel_psr2_program_plane_sel_fetch(struct intel_plane *plane,
>  					const struct intel_crtc_state *crtc_state,
>  					const struct intel_plane_state *plane_state,
>  					int color_plane);
> +void intel_psr_pause(struct intel_dp *intel_dp);
> +void intel_psr_resume(struct intel_dp *intel_dp);
>  
>  #endif /* __INTEL_PSR_H__ */