[Intel-gfx] [PATCH 15/21] drm/i915: Extract bxt DE PLL enable/disable from broxton_set_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>
> 
> Enabling and disalbing the DE PLL are two nice self contained
> operations, so let's move them into a few small helper functions.
> Makes it easier to see the forest from the trees in broxton_set_cdclk().
> 
> 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 | 41 ++++++++++++++++++++++++------------
>  1 file changed, 27 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 11e90863533b..76d59d1214f4 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -5358,6 +5358,31 @@ static int skl_cdclk_decimal(int cdclk)
>  	return DIV_ROUND_CLOSEST(cdclk - 1000, 500);
>  }
>  
> +static void bxt_de_pll_disable(struct drm_i915_private *dev_priv)
> +{
> +	I915_WRITE(BXT_DE_PLL_ENABLE, 0);
> +
> +	/* Timeout 200us */
> +	if (wait_for((I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK) == 0, 1))
> +		DRM_ERROR("timeout waiting for DE PLL unlock\n");
> +}
> +
> +static void bxt_de_pll_enable(struct drm_i915_private *dev_priv, u32 ratio)
> +{
> +	u32 val;
> +
> +	val = I915_READ(BXT_DE_PLL_CTL);
> +	val &= ~BXT_DE_PLL_RATIO_MASK;
> +	val |= ratio;
> +	I915_WRITE(BXT_DE_PLL_CTL, val);
> +
> +	I915_WRITE(BXT_DE_PLL_ENABLE, BXT_DE_PLL_PLL_ENABLE);
> +
> +	/* Timeout 200us */
> +	if (wait_for((I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK) != 0, 1))
> +		DRM_ERROR("timeout waiting for DE PLL lock\n");
> +}
> +
>  static void broxton_set_cdclk(struct drm_i915_private *dev_priv, int cdclk)
>  {
>  	uint32_t divider;
> @@ -5425,25 +5450,13 @@ static void broxton_set_cdclk(struct drm_i915_private *dev_priv, int cdclk)
>  	 */
>  	if (cdclk == 19200 || cdclk == 624000 ||
>  	    current_cdclk == 624000) {
> -		I915_WRITE(BXT_DE_PLL_ENABLE, ~BXT_DE_PLL_PLL_ENABLE);
> -		/* Timeout 200us */
> -		if (wait_for(!(I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK),
> -			     1))
> -			DRM_ERROR("timout waiting for DE PLL unlock\n");
> +		bxt_de_pll_disable(dev_priv);
>  	}
>  
>  	if (cdclk != 19200) {
>  		uint32_t val;
>  
> -		val = I915_READ(BXT_DE_PLL_CTL);
> -		val &= ~BXT_DE_PLL_RATIO_MASK;
> -		val |= ratio;
> -		I915_WRITE(BXT_DE_PLL_CTL, val);
> -
> -		I915_WRITE(BXT_DE_PLL_ENABLE, BXT_DE_PLL_PLL_ENABLE);
> -		/* Timeout 200us */
> -		if (wait_for(I915_READ(BXT_DE_PLL_ENABLE) & BXT_DE_PLL_LOCK, 1))
> -			DRM_ERROR("timeout waiting for DE PLL lock\n");
> +		bxt_de_pll_enable(dev_priv, ratio);
>  
>  		val = divider | skl_cdclk_decimal(cdclk);
>  		/*