[Intel-gfx] [PATCH 6/8] drm/i915: Use cdclk_state->voltage on BXT/GLK

[Rodrigo Vivi]

On Wed, Oct 18, 2017 at 08:48:23PM +0000, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Track the system agent voltage we request from pcode in the cdclk state
> on BXT/GLK. Annoyingly we can't actually read out the current value since
> there's no pcode command to do that, so we'll have to just assume that
> it worked.
> 
> Cc: Mika Kahola <mika.kahola at intel.com>
> Cc: Manasi Navare <manasi.d.navare at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_cdclk.c | 20 ++++++++++++++++++--
>  1 file changed, 18 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c
> index 6f7b5abe6e3f..1b4dcd9689da 100644
> --- a/drivers/gpu/drm/i915/intel_cdclk.c
> +++ b/drivers/gpu/drm/i915/intel_cdclk.c
> @@ -1166,6 +1166,11 @@ static int glk_calc_cdclk(int min_cdclk)
>  		return 79200;
>  }
>  
> +static u8 bxt_calc_voltage(int cdclk)
> +{
> +	return DIV_ROUND_UP(cdclk, 25000);
> +}
> +
>  static int bxt_de_pll_vco(struct drm_i915_private *dev_priv, int cdclk)
>  {
>  	int ratio;
> @@ -1242,7 +1247,7 @@ static void bxt_get_cdclk(struct drm_i915_private *dev_priv,
>  	cdclk_state->cdclk = cdclk_state->ref;
>  
>  	if (cdclk_state->vco == 0)
> -		return;
> +		goto out;
>  
>  	divider = I915_READ(CDCLK_CTL) & BXT_CDCLK_CD2X_DIV_SEL_MASK;
>  
> @@ -1266,6 +1271,13 @@ static void bxt_get_cdclk(struct drm_i915_private *dev_priv,
>  	}
>  
>  	cdclk_state->cdclk = DIV_ROUND_CLOSEST(cdclk_state->vco, div);
> +
> + out:
> +	/*
> +	 * Can't read this out :( Let's assume it's
> +	 * at least what the CDCLK frequency requires.
> +	 */
> +	cdclk_state->voltage = bxt_calc_voltage(cdclk_state->cdclk);
>  }
>  
>  static void bxt_de_pll_disable(struct drm_i915_private *dev_priv)
> @@ -1368,7 +1380,7 @@ static void bxt_set_cdclk(struct drm_i915_private *dev_priv,
>  
>  	mutex_lock(&dev_priv->pcu_lock);
>  	ret = sandybridge_pcode_write(dev_priv, HSW_PCODE_DE_WRITE_FREQ_REQ,
> -				      DIV_ROUND_UP(cdclk, 25000));
> +				      cdclk_state->voltage);
>  	mutex_unlock(&dev_priv->pcu_lock);
>  
>  	if (ret) {
> @@ -1460,6 +1472,7 @@ void bxt_init_cdclk(struct drm_i915_private *dev_priv)
>  		cdclk_state.cdclk = bxt_calc_cdclk(0);
>  		cdclk_state.vco = bxt_de_pll_vco(dev_priv, cdclk_state.cdclk);
>  	}
> +	cdclk_state.voltage = bxt_calc_voltage(cdclk_state.cdclk);
>  
>  	bxt_set_cdclk(dev_priv, &cdclk_state);
>  }
> @@ -1477,6 +1490,7 @@ void bxt_uninit_cdclk(struct drm_i915_private *dev_priv)
>  
>  	cdclk_state.cdclk = cdclk_state.ref;
>  	cdclk_state.vco = 0;
> +	cdclk_state.voltage = bxt_calc_voltage(cdclk_state.cdclk);
>  
>  	bxt_set_cdclk(dev_priv, &cdclk_state);
>  }
> @@ -2030,6 +2044,7 @@ static int bxt_modeset_calc_cdclk(struct drm_atomic_state *state)
>  
>  	intel_state->cdclk.logical.vco = vco;
>  	intel_state->cdclk.logical.cdclk = cdclk;
> +	intel_state->cdclk.logical.voltage = bxt_calc_voltage(cdclk);
>  
>  	if (!intel_state->active_crtcs) {
>  		if (IS_GEMINILAKE(dev_priv)) {
> @@ -2042,6 +2057,7 @@ static int bxt_modeset_calc_cdclk(struct drm_atomic_state *state)
>  
>  		intel_state->cdclk.actual.vco = vco;
>  		intel_state->cdclk.actual.cdclk = cdclk;
> +		intel_state->cdclk.actual.voltage = bxt_calc_voltage(cdclk);
>  	} else {
>  		intel_state->cdclk.actual =
>  			intel_state->cdclk.logical;
> -- 
> 2.13.6
>