Re: [Intel-gfx] [PATCH 04/14] drm/i915: Move drrs hardware bit frobbing to small helpers

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 27 Jan 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Split the drrs code that actually changes the refresh rate
> (via PIPECONF or M/N values) to small helper functions that
> only deal with the hardware details an nothing else. We'll
> soon have a third way of doing this, and it's less confusing
> when each difference method lives in its own funciton.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_drrs.c | 67 ++++++++++++-----------
>  1 file changed, 36 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_drrs.c b/drivers/gpu/drm/i915/display/intel_drrs.c
> index 46be46f2c47e..0cacdb174fd0 100644
> --- a/drivers/gpu/drm/i915/display/intel_drrs.c
> +++ b/drivers/gpu/drm/i915/display/intel_drrs.c
> @@ -87,6 +87,38 @@ intel_drrs_compute_config(struct intel_dp *intel_dp,
>  		pipe_config->dp_m2_n2.data_m *= pipe_config->splitter.link_count;
>  }
>  
> +static void
> +intel_drrs_set_refresh_rate_pipeconf(const struct intel_crtc_state *crtc_state,
> +				     enum drrs_refresh_rate_type refresh_type)

Side note, for future, does this really need to be an enum? Could it
just be a bool "reduced" or something?

Anyway,

Reviewed-by: Jani Nikula <jani.nikula@intel.com>



> +{
> +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> +	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> +	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> +	u32 val, bit;
> +
> +	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> +		bit = PIPECONF_EDP_RR_MODE_SWITCH_VLV;
> +	else
> +		bit = PIPECONF_EDP_RR_MODE_SWITCH;
> +
> +	val = intel_de_read(dev_priv, PIPECONF(cpu_transcoder));
> +
> +	if (refresh_type == DRRS_LOW_RR)
> +		val |= bit;
> +	else
> +		val &= ~bit;
> +
> +	intel_de_write(dev_priv, PIPECONF(cpu_transcoder), val);
> +}
> +
> +static void
> +intel_drrs_set_refresh_rate_m_n(const struct intel_crtc_state *crtc_state,
> +				enum drrs_refresh_rate_type refresh_type)
> +{
> +	intel_dp_set_m_n(crtc_state,
> +			 refresh_type == DRRS_LOW_RR ? M2_N2 : M1_N1);
> +}
> +
>  static void intel_drrs_set_state(struct drm_i915_private *dev_priv,
>  				 const struct intel_crtc_state *crtc_state,
>  				 enum drrs_refresh_rate_type refresh_type)
> @@ -120,37 +152,10 @@ static void intel_drrs_set_state(struct drm_i915_private *dev_priv,
>  		return;
>  	}
>  
> -	if (DISPLAY_VER(dev_priv) >= 8 && !IS_CHERRYVIEW(dev_priv)) {
> -		switch (refresh_type) {
> -		case DRRS_HIGH_RR:
> -			intel_dp_set_m_n(crtc_state, M1_N1);
> -			break;
> -		case DRRS_LOW_RR:
> -			intel_dp_set_m_n(crtc_state, M2_N2);
> -			break;
> -		case DRRS_MAX_RR:
> -		default:
> -			drm_err(&dev_priv->drm,
> -				"Unsupported refreshrate type\n");
> -		}
> -	} else if (DISPLAY_VER(dev_priv) > 6) {
> -		i915_reg_t reg = PIPECONF(crtc_state->cpu_transcoder);
> -		u32 val;
> -
> -		val = intel_de_read(dev_priv, reg);
> -		if (refresh_type == DRRS_LOW_RR) {
> -			if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> -				val |= PIPECONF_EDP_RR_MODE_SWITCH_VLV;
> -			else
> -				val |= PIPECONF_EDP_RR_MODE_SWITCH;
> -		} else {
> -			if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> -				val &= ~PIPECONF_EDP_RR_MODE_SWITCH_VLV;
> -			else
> -				val &= ~PIPECONF_EDP_RR_MODE_SWITCH;
> -		}
> -		intel_de_write(dev_priv, reg, val);
> -	}
> +	if (DISPLAY_VER(dev_priv) >= 8 && !IS_CHERRYVIEW(dev_priv))
> +		intel_drrs_set_refresh_rate_m_n(crtc_state, refresh_type);
> +	else if (DISPLAY_VER(dev_priv) > 6)
> +		intel_drrs_set_refresh_rate_pipeconf(crtc_state, refresh_type);
>  
>  	dev_priv->drrs.refresh_rate_type = refresh_type;

-- 
Jani Nikula, Intel Open Source Graphics Center