[Intel-gfx] [PATCH 6/9] drm/i915: Check pixel clock when setting mode for DSI

[Chris Wilson]

On Fri, Jul 03, 2015 at 02:35:54PM +0300, Mika Kahola wrote:
> It is possible the we request to have a mode that has
> higher pixel clock than our HW can support. This patch
> checks if requested pixel clock is lower than the one
> supported by the HW. The requested mode is discarded
> if we cannot support the requested pixel clock.
> 
> This patch applies to DSI.
> 
> Signed-off-by: Mika Kahola <mika.kahola at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 98998e9..1cf35b8 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -635,15 +635,39 @@ static void intel_dsi_get_config(struct intel_encoder *encoder,
>  	pipe_config->port_clock = pclk;
>  }
>  
> +static int
> +intel_dsi_max_pixclk(struct intel_dsi *intel_dsi)
> +{
> +	struct drm_device *dev = intel_dsi->base.base.dev;
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	struct intel_crtc *intel_crtc = to_intel_crtc(intel_dsi->base.base.crtc);
> +
> +	if (IS_CHERRYVIEW(dev))
> +		return  DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 95);
> +	else if (IS_VALLEYVIEW(dev))
> +		return  DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 90);
> +	else if (IS_BROADWELL(dev) && intel_crtc->config->ips_enabled)
> +		return  DIV_ROUND_UP(dev_priv->max_cdclk_freq * 100, 95);
> +	else
> +		return dev_priv->max_cdclk_freq;
> +}
> +
>  static enum drm_mode_status
>  intel_dsi_mode_valid(struct drm_connector *connector,
>  		     struct drm_display_mode *mode)
>  {
>  	struct intel_connector *intel_connector = to_intel_connector(connector);
>  	struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
> +	struct intel_encoder *intel_encoder = intel_connector->encoder;
> +	struct drm_encoder *encoder = &intel_encoder->base;
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
> +	int max_pixclk = intel_dsi_max_pixclk(intel_dsi);
>  
>  	DRM_DEBUG_KMS("\n");
>  
> +	if (mode->clock > max_pixclk)
> +		return MODE_PANEL;

return MODE_CLOCK_HIGH;
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre