[Intel-gfx] [PATCH 1/2] drm/i915: Check if PSR is globally enabled before change PSR variables

[Dhinakaran Pandiyan]

On Thu, 2018-11-29 at 18:31 -0800, José Roberto de Souza wrote:
> There is no issues changing the PSR variables even if PSR will be not
> enabled but it avoid having misleading values like have psr2_enabled
> set but enabled unset.
> 
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_psr.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_psr.c
> b/drivers/gpu/drm/i915/intel_psr.c
> index 2084784f320d..827b8c31783d 100644
> --- a/drivers/gpu/drm/i915/intel_psr.c
> +++ b/drivers/gpu/drm/i915/intel_psr.c
> @@ -716,14 +716,15 @@ void intel_psr_enable(struct intel_dp
> *intel_dp,
>  		goto unlock;
>  	}
>  
> +	if (!psr_global_enabled(dev_priv->psr.debug)) {
> +		DRM_DEBUG_KMS("PSR disabled by flag\n");
> +		goto unlock;
> +	}
> +
>  	dev_priv->psr.psr2_enabled = intel_psr2_enabled(dev_priv,
> crtc_state);
>  	dev_priv->psr.busy_frontbuffer_bits = 0;
>  	dev_priv->psr.prepared = true;
.prepared needs to be set even when psr_global_enabled() returns false.
This is so that we can enable PSR via debugfs later.

> -
> -	if (psr_global_enabled(dev_priv->psr.debug))
> -		intel_psr_enable_locked(dev_priv, crtc_state);
> -	else
> -		DRM_DEBUG_KMS("PSR disabled by flag\n");
> +	intel_psr_enable_locked(dev_priv, crtc_state);
>  
>  unlock:
>  	mutex_unlock(&dev_priv->psr.lock);