[Intel-gfx] [PATCH] drm/i915/psr: Enable PSR1 by default on gen9+ platforms

[Rodrigo Vivi]

On Wed, Jul 25, 2018 at 12:22:28AM -0700, Dhinakaran Pandiyan wrote:
> We have merged several fixes, re-written some tests and improved debug
> capability in the past several months, so this is a good time to give PSR1
> another try. PSR1 has not been tested on HSW and BDW recently, so let's
> enable only on gen9+ now.
> 
> Cc: Rodigo Vivi <rodrigo.vivi at intel.com>
> Cc: José Roberto de Souza <jose.souza at intel.com>
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_psr.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
> index 4bd5768731ee..942db85da6a1 100644
> --- a/drivers/gpu/drm/i915/intel_psr.c
> +++ b/drivers/gpu/drm/i915/intel_psr.c
> @@ -471,10 +471,8 @@ void intel_psr_compute_config(struct intel_dp *intel_dp,
>  	if (!CAN_PSR(dev_priv))
>  		return;
>  
> -	if (!i915_modparams.enable_psr) {
> -		DRM_DEBUG_KMS("PSR disable by flag\n");

Why are you removing the message?
I think it is still useful... and enable_psr == -1 doesn't trigger that.

> +	if (!i915_modparams.enable_psr)
>  		return;
> -	}
>  
>  	/*
>  	 * HSW spec explicitly says PSR is tied to port A.
> @@ -516,7 +514,11 @@ void intel_psr_compute_config(struct intel_dp *intel_dp,
>  	}
>  
>  	crtc_state->has_psr = true;
> -	crtc_state->has_psr2 = intel_psr2_config_valid(intel_dp, crtc_state);
> +
> +	/* Enable only PSR 1 by default for now */
> +	crtc_state->has_psr2 = i915_modparams.enable_psr == 1 &&
> +			       intel_psr2_config_valid(intel_dp, crtc_state);
> +

this might get confusing...
-1 - enable psr1
0 - disable
1 - enable psr2

and far from the variable... Well... I want to kill the parameter anyways
so no hard feelings on having this here, but what about some debug messages
at least?

/* Enable only PSR1 by default for now */
if (i915_modparams.enable_psr == -1) {
	DRM_DEBUG_KMS("Avoiding PSR2 by platform default")
	crtc_state->has_psr2 = 0;
} else {
	crtc_state->has_psr2 = intel_psr2_config_valid(intel_dp, crtc_state);
}

>  	DRM_DEBUG_KMS("Enabling PSR%s\n", crtc_state->has_psr2 ? "2" : "");
>  }
>  
> @@ -956,12 +958,10 @@ void intel_psr_init(struct drm_i915_private *dev_priv)
>  	if (!dev_priv->psr.sink_support)
>  		return;
>  
> -	if (i915_modparams.enable_psr == -1) {
> -		i915_modparams.enable_psr = dev_priv->vbt.psr.enable;
> -
> -		/* Per platform default: all disabled. */
> -		i915_modparams.enable_psr = 0;
> -	}
> +	/* Enable PSR 1 default only on gen9+ */
> +	if (i915_modparams.enable_psr == -1)
> +		if (INTEL_GEN(dev_priv) < 9 || !dev_priv->vbt.psr.enable)
> +			i915_modparams.enable_psr = 0;

we talked about this in person, but just for the record:
we need to check cnl and icl on CI for psr cases before make this > 9.

>
>  	/* Set link_standby x link_off defaults */
>  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
> -- 
> 2.17.1
>