[Intel-gfx] [PATCH v3] drm/i915/display: Force the state compute phase once to enable PSR

[Mun, Gwan-gyeong]

On Mon, 2020-01-06 at 07:21 -0800, José Roberto de Souza wrote:
> Recent improvements in the state tracking in i915 caused PSR to not
> be
> enabled when reusing firmware/BIOS modeset, this is due to all
> initial
> commits returning ealier in intel_atomic_check() as needs_modeset()
> is always false.
> 
> To fix that here forcing the state compute phase in CRTC that is
> driving the eDP that supports PSR once. Enable or disable PSR do not
> require a fullmodeset, so user will still experience glitch free boot
> process plus the power savings that PSR brings.
> 
> It was tried to set mode_changed in intel_initial_commit() but at
> this point the connectors are not registered causing a crash when
> computing encoder state.
> 
> v2:
> - removed function return
> - change arguments to match intel_hdcp_atomic_check
> 
> v3:
> - replaced drm includes in intel_psr.h by forward declaration(Jani)
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112253
> Reported-by: <s.zharkoff at gmail.com>
> Cc: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
> Cc: Jani Nikula <jani.nikula at intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_atomic.c |  2 ++
>  drivers/gpu/drm/i915/display/intel_psr.c    | 24
> +++++++++++++++++++++
>  drivers/gpu/drm/i915/display/intel_psr.h    |  5 +++++
>  drivers/gpu/drm/i915/i915_drv.h             |  1 +
>  4 files changed, 32 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c
> b/drivers/gpu/drm/i915/display/intel_atomic.c
> index 0eb973f65977..c362eecdd414 100644
> --- a/drivers/gpu/drm/i915/display/intel_atomic.c
> +++ b/drivers/gpu/drm/i915/display/intel_atomic.c
> @@ -37,6 +37,7 @@
>  #include "intel_atomic.h"
>  #include "intel_display_types.h"
>  #include "intel_hdcp.h"
> +#include "intel_psr.h"
>  #include "intel_sprite.h"
>  
>  /**
> @@ -129,6 +130,7 @@ int intel_digital_connector_atomic_check(struct
> drm_connector *conn,
>  	struct drm_crtc_state *crtc_state;
>  
>  	intel_hdcp_atomic_check(conn, old_state, new_state);
> +	intel_psr_atomic_check(conn, old_state, new_state);
>  
>  	if (!new_state->crtc)
>  		return 0;
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> b/drivers/gpu/drm/i915/display/intel_psr.c
> index 16e9ff47d519..e3fd5f1e2d21 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -1523,3 +1523,27 @@ bool intel_psr_enabled(struct intel_dp
> *intel_dp)
>  
>  	return ret;
>  }
> +
> +void intel_psr_atomic_check(struct drm_connector *connector,
> +			    struct drm_connector_state *old_state,
> +			    struct drm_connector_state *new_state)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->dev);
> +	struct intel_connector *intel_connector;
> +	struct intel_digital_port *dig_port;
> +	struct drm_crtc_state *crtc_state;
> +
> +	if (!CAN_PSR(dev_priv) || !new_state->crtc ||
> +	    dev_priv->psr.initially_probed)
> +		return;
> +
> +	intel_connector = to_intel_connector(connector);
> +	dig_port = enc_to_dig_port(&intel_connector->encoder->base);
> +	if (dev_priv->psr.dp != &dig_port->dp)
> +		return;
> +
> +	crtc_state = drm_atomic_get_new_crtc_state(new_state->state,
> +						   new_state->crtc);
> +	crtc_state->mode_changed = true;
> +	dev_priv->psr.initially_probed = true;
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.h
> b/drivers/gpu/drm/i915/display/intel_psr.h
> index 46e4de8b8cd5..c58a1d438808 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.h
> +++ b/drivers/gpu/drm/i915/display/intel_psr.h
> @@ -8,6 +8,8 @@
>  
>  #include "intel_frontbuffer.h"
>  
> +struct drm_connector;
> +struct drm_connector_state;
>  struct drm_i915_private;
>  struct intel_crtc_state;
>  struct intel_dp;
> @@ -35,5 +37,8 @@ void intel_psr_short_pulse(struct intel_dp
> *intel_dp);
>  int intel_psr_wait_for_idle(const struct intel_crtc_state
> *new_crtc_state,
>  			    u32 *out_value);
>  bool intel_psr_enabled(struct intel_dp *intel_dp);
> +void intel_psr_atomic_check(struct drm_connector *connector,
> +			    struct drm_connector_state *old_state,
> +			    struct drm_connector_state *new_state);
>  
>  #endif /* __INTEL_PSR_H__ */
> diff --git a/drivers/gpu/drm/i915/i915_drv.h
> b/drivers/gpu/drm/i915/i915_drv.h
> index 50181113dd2b..1025d783f494 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -505,6 +505,7 @@ struct i915_psr {
>  	bool dc3co_enabled;
>  	u32 dc3co_exit_delay;
>  	struct delayed_work idle_work;
> +	bool initially_probed;
>  };
>  
>  #define QUIRK_LVDS_SSC_DISABLE (1<<1)
Looks good to me.
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>