[Intel-gfx] [PATCH] drm/i915/psr: Enable PSR1 on gen-9+ HW

[Rodrigo Vivi]

On Thu, Sep 06, 2018 at 04:52:02PM -0700, Dhinakaran Pandiyan wrote:
> We have new tests and fixes in place since the feature was last
> disabled.
> 
> Try again for gen-9+ hardware and enable only PSR1 as a first step.
> 
> Cc: Jani Nikula <jani.nikula at intel.com>
> Cc: Jose Roberto de Souza <jose.souza at intel.com>
> Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> References: commit 2ee7dc497e34 ("drm/i915: disable PSR by default on HSW/BDW")
> References: commit dcb2e993f3c0 ("Revert "drm/i915: Enable PSR by default on Valleyview and Cherryview."")
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_psr.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
> index b6838b525502..fc823f93a4dc 100644
> --- a/drivers/gpu/drm/i915/intel_psr.c
> +++ b/drivers/gpu/drm/i915/intel_psr.c
> @@ -71,6 +71,10 @@ static bool psr_global_enabled(u32 debug)
>  static bool intel_psr2_enabled(struct drm_i915_private *dev_priv,
>  			       const struct intel_crtc_state *crtc_state)
>  {
> +	/* Disable PSR2 by default for all platforms */
> +	if (i915_modparams.enable_psr == -1)
> +		return false;
> +
>  	switch (dev_priv->psr.debug & I915_PSR_DEBUG_MODE_MASK) {
>  	case I915_PSR_DEBUG_FORCE_PSR1:
>  		return false;
> @@ -1051,7 +1055,7 @@ void intel_psr_flush(struct drm_i915_private *dev_priv,
>   * intel_psr_init - Init basic PSR work and mutex.
>   * @dev_priv: i915 device private
>   *
> - * This function is  called only once at driver load to initialize basic
> + * This function is called only once at driver load to initialize basic
>   * PSR stuff.
>   */
>  void intel_psr_init(struct drm_i915_private *dev_priv)
> @@ -1065,19 +1069,14 @@ 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;
> -	}
> +	if (i915_modparams.enable_psr == -1)
> +		if (INTEL_GEN(dev_priv) < 9 || !dev_priv->vbt.psr.enable)
> +			i915_modparams.enable_psr = 0;
>  
> -	/* Set link_standby x link_off defaults */
>  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
>  		/* HSW and BDW require workarounds that we don't implement. */
>  		dev_priv->psr.link_standby = false;
>  	else
> -		/* For new platforms let's respect VBT back again */

bikeshed: Can we please leave the clean-up for a separated patch?
In case we need to revert we don't loose the clean-up part! :$

Also a bikeshed of bikeshed: I think we need to revisit this block entirely
anyways. I can't remember why we stopped respecting the bspec here.
And probably this was only masking some issues that got fixed during
your great journey! ;)

Maybe this block even explain the current gap on hsw and bdw?! ;)

>  		dev_priv->psr.link_standby = dev_priv->vbt.psr.full_link;
>  
>  	INIT_WORK(&dev_priv->psr.work, intel_psr_work);
> -- 
> 2.17.1
>