[Intel-gfx] [PATCH 04/21] drm/i915: Extract skl_calc_cdclk()

[Imre Deak]

On pe, 2016-05-13 at 23:41 +0300, ville.syrjala at linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> We have many places where we want to pick a suitable cdclk frequency for
> skl based on the dotclock and lcpll vco. Split that code into a small
> helper and call it from all over.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Reviewed-by: Imre Deak <imre.deak at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_display.c | 63 +++++++++++++++++-------------------
>  1 file changed, 30 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 41fe18c4b761..c1b1632664a1 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -5527,6 +5527,30 @@ void broxton_uninit_cdclk(struct drm_i915_private *dev_priv)
>  	broxton_set_cdclk(dev_priv, 19200);
>  }
>  
> +static int skl_calc_cdclk(int max_pixclk, int vco)
> +{
> +	if (vco == 8640) {
> +		if (max_pixclk > 540000)
> +			return 617140;
> +		else if (max_pixclk > 432000)
> +			return 540000;
> +		else if (max_pixclk > 308570)
> +			return 432000;
> +		else
> +			return 308570;
> +	} else {
> +		/* VCO 8100 */
> +		if (max_pixclk > 540000)
> +			return 675000;
> +		else if (max_pixclk > 450000)
> +			return 540000;
> +		else if (max_pixclk > 337500)
> +			return 450000;
> +		else
> +			return 337500;
> +	}
> +}
> +
>  static const struct skl_cdclk_entry {
>  	unsigned int freq;
>  	unsigned int vco;
> @@ -5557,15 +5581,10 @@ unsigned int skl_cdclk_get_vco(unsigned int freq)
>  static void
>  skl_dpll0_enable(struct drm_i915_private *dev_priv, int vco)
>  {
> -	int min_cdclk;
> +	int min_cdclk = skl_calc_cdclk(0, vco);
>  	u32 val;
>  
>  	/* select the minimum CDCLK before enabling DPLL 0 */
> -	if (vco == 8640)
> -		min_cdclk = 308570;
> -	else
> -		min_cdclk = 337500;
> -
>  	val = CDCLK_FREQ_337_308 | skl_cdclk_decimal(min_cdclk);
>  	I915_WRITE(CDCLK_CTL, val);
>  	POSTING_READ(CDCLK_CTL);
> @@ -5577,7 +5596,7 @@ skl_dpll0_enable(struct drm_i915_private *dev_priv, int vco)
>  	 * 8100 while the eDP 1.4 alternate link rates need a VCO of 8640.
>  	 * The modeset code is responsible for the selection of the exact link
>  	 * rate later on, with the constraint of choosing a frequency that
> -	 * works with required_vco.
> +	 * works with vco.
>  	 */
>  	val = I915_READ(DPLL_CTRL1);
>  
> @@ -5706,7 +5725,7 @@ void skl_init_cdclk(struct drm_i915_private *dev_priv)
>  		if (dev_priv->skl_vco_freq != 8640)
>  			dev_priv->skl_vco_freq = 8100;
>  		skl_dpll0_enable(dev_priv, dev_priv->skl_vco_freq);
> -		cdclk = ((dev_priv->skl_vco_freq == 8100) ? 337500 : 308570);
> +		cdclk = skl_calc_cdclk(0, dev_priv->skl_vco_freq);
>  	} else {
>  		cdclk = dev_priv->cdclk_freq;
>  	}
> @@ -9724,34 +9743,14 @@ static int skl_modeset_calc_cdclk(struct drm_atomic_state *state)
>  	struct intel_atomic_state *intel_state = to_intel_atomic_state(state);
>  	struct drm_i915_private *dev_priv = to_i915(state->dev);
>  	const int max_pixclk = ilk_max_pixel_rate(state);
> +	int vco = intel_state->cdclk_pll_vco;
>  	int cdclk;
>  
>  	/*
>  	 * FIXME should also account for plane ratio
>  	 * once 64bpp pixel formats are supported.
>  	 */
> -
> -	if (intel_state->cdclk_pll_vco == 8640) {
> -		/* vco 8640 */
> -		if (max_pixclk > 540000)
> -			cdclk = 617140;
> -		else if (max_pixclk > 432000)
> -			cdclk = 540000;
> -		else if (max_pixclk > 308570)
> -			cdclk = 432000;
> -		else
> -			cdclk = 308570;
> -	} else {
> -		/* VCO 8100 */
> -		if (max_pixclk > 540000)
> -			cdclk = 675000;
> -		else if (max_pixclk > 450000)
> -			cdclk = 540000;
> -		else if (max_pixclk > 337500)
> -			cdclk = 450000;
> -		else
> -			cdclk = 337500;
> -	}
> +	cdclk = skl_calc_cdclk(max_pixclk, vco);
>  
>  	/*
>  	 * FIXME move the cdclk caclulation to
> @@ -9765,9 +9764,7 @@ static int skl_modeset_calc_cdclk(struct drm_atomic_state *state)
>  
>  	intel_state->cdclk = intel_state->dev_cdclk = cdclk;
>  	if (!intel_state->active_crtcs)
> -		intel_state->dev_cdclk = ((intel_state->cdclk_pll_vco == 8640) ?
> -					   308570 : 337500);
> -
> +		intel_state->dev_cdclk = skl_calc_cdclk(0, vco);
>  
>  	return 0;
>  }