[Intel-gfx] [PATCH 07/21] drm/i915: Helper function to update skylake scaling ratio.

[Matt Roper]

On Sat, Mar 14, 2015 at 10:55:32PM -0700, Chandra Konduru wrote:
> Helper function updates supported scaling ratios based on cdclk and
> crtc clocks.

It might be worth squashing this into patch 15, which I believe is when
you first start using this.  It's a little but harder to review new
functions like this without the context of how/why/when they're called.

> 
> Signed-off-by: Chandra Konduru <chandra.konduru at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c |   25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index da78e77..5591282 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -4511,6 +4511,31 @@ static void haswell_mode_set_planes_workaround(struct intel_crtc *crtc)
>  	intel_wait_for_vblank(dev, other_active_crtc->pipe);
>  }
>  
> +static void skl_update_scaling_ratio(struct drm_device *dev,
> +	struct intel_crtc_state *crtc_state)
> +{
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	uint32_t crtc_clock, cdclk;
> +	int i;
> +
> +	if (INTEL_INFO(dev)->gen < 9 || !crtc_state)
> +		return;

I wouldn't expect a skl_ function to even get called on gen<9.  Or for a
NULL CRTC state to be passed in.


> +
> +	crtc_clock = (uint32_t) crtc_state->base.adjusted_mode.crtc_clock;
> +	cdclk = (uint32_t) intel_ddi_get_cdclk_freq(dev_priv);
> +
> +	if (!crtc_clock || !cdclk)
> +		return;
> +
> +	for (i = 0; i < crtc_state->scaler_state.num_scalers; i++) {
> +		struct intel_scaler *scaler = &crtc_state->scaler_state.scalers[i];
> +
> +		scaler->min_hsr = max(scaler->min_hsr, (crtc_clock * 100)/cdclk);
> +		scaler->min_vsr = max(scaler->min_hsr, (crtc_clock * 100)/cdclk);
> +		scaler->min_hvsr = max(scaler->min_hsr, (crtc_clock * 100)/cdclk);
> +	}
> +}
> +
>  static void haswell_crtc_enable(struct drm_crtc *crtc)
>  {
>  	struct drm_device *dev = crtc->dev;
> -- 
> 1.7.9.5
> 

-- 
Matt Roper
Graphics Software Engineer
IoTG Platform Enabling & Development
Intel Corporation
(916) 356-2795