Re: [Intel-gfx] [PATCH 3/4] drm/i915: Keep sagv status updated on icl+

["Lisovskiy, Stanislav" <stanislav.lisovskiy@intel.com>]

On Tue, Jan 31, 2023 at 02:21:26AM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> On icl+ SAGV is controlled by masking of the QGV points.
> Reduce the QGV point mask to the same kind of enabled vs.
> disable information that we had on previous platforms.
> Will be useful in answering the question whether SAGV is
> actually enabled or not.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_bw.c | 49 +++++++++++++++----------
>  1 file changed, 29 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
> index 1c236f02b380..202321ffbe2a 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.c
> +++ b/drivers/gpu/drm/i915/display/intel_bw.c
> @@ -119,6 +119,32 @@ static int adls_pcode_read_psf_gv_point_info(struct drm_i915_private *dev_priv,
>  	return 0;
>  }
>  
> +static u16 icl_qgv_points_mask(struct drm_i915_private *i915)
> +{
> +	unsigned int num_psf_gv_points = i915->display.bw.max[0].num_psf_gv_points;
> +	unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points;
> +	u16 qgv_points = 0, psf_points = 0;
> +
> +	/*
> +	 * We can _not_ use the whole ADLS_QGV_PT_MASK here, as PCode rejects
> +	 * it with failure if we try masking any unadvertised points.
> +	 * So need to operate only with those returned from PCode.
> +	 */
> +	if (num_qgv_points > 0)
> +		qgv_points = GENMASK(num_qgv_points - 1, 0);
> +
> +	if (num_psf_gv_points > 0)
> +		psf_points = GENMASK(num_psf_gv_points - 1, 0);
> +
> +	return ICL_PCODE_REQ_QGV_PT(qgv_points) | ADLS_PCODE_REQ_PSF_PT(psf_points);
> +}
> +
> +static bool is_sagv_enabled(struct drm_i915_private *i915, u16 points_mask)
> +{
> +	return !is_power_of_2(~points_mask & icl_qgv_points_mask(i915) &
> +			      ICL_PCODE_REQ_QGV_PT_MASK);
> +}
> +
>  int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv,
>  				  u32 points_mask)
>  {
> @@ -136,6 +162,9 @@ int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv,
>  		return ret;
>  	}
>  
> +	dev_priv->display.sagv.status = is_sagv_enabled(dev_priv, points_mask) ?
> +		I915_SAGV_ENABLED : I915_SAGV_DISABLED;
> +
>  	return 0;
>  }
>  
> @@ -965,26 +994,6 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state *state,
>  	return 0;
>  }
>  
> -static u16 icl_qgv_points_mask(struct drm_i915_private *i915)
> -{
> -	unsigned int num_psf_gv_points = i915->display.bw.max[0].num_psf_gv_points;
> -	unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points;
> -	u16 qgv_points = 0, psf_points = 0;
> -
> -	/*
> -	 * We can _not_ use the whole ADLS_QGV_PT_MASK here, as PCode rejects
> -	 * it with failure if we try masking any unadvertised points.
> -	 * So need to operate only with those returned from PCode.
> -	 */
> -	if (num_qgv_points > 0)
> -		qgv_points = GENMASK(num_qgv_points - 1, 0);
> -
> -	if (num_psf_gv_points > 0)
> -		psf_points = GENMASK(num_psf_gv_points - 1, 0);
> -
> -	return ICL_PCODE_REQ_QGV_PT(qgv_points) | ADLS_PCODE_REQ_PSF_PT(psf_points);
> -}
> -
>  static int intel_bw_check_data_rate(struct intel_atomic_state *state, bool *changed)
>  {
>  	struct drm_i915_private *i915 = to_i915(state->base.dev);
> -- 
> 2.39.1
>