[Intel-gfx] [PATCH] drm/i915: Add missing NULL check before calling initial_watermarks

[Matt Roper]

On Mon, Feb 29, 2016 at 09:20:35PM +0200, Imre Deak wrote:
> Not all platforms set this callback, so NULL check it before calling it.
> 
> CC: Matt Roper <matthew.d.roper at intel.com>
> Fixes: commit ed4a6a7c ("drm/i915: Add two-stage ILK-style watermark programming (v11)")
> Signed-off-by: Imre Deak <imre.deak at intel.com>

Oh, looks like gen9 is using the HSW enable, so yeah, we want to add the
test there.  But we probably want an 'else' as well that calls
intel_update_watermarks(crtc) until we've converted the SKL-style code
over.

I'm not sure why this didn't raise any CI errors?  Seems like something
that should have been easily caught by the BAT tests...


Matt

> ---
>  drivers/gpu/drm/i915/intel_display.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 79bf527..a60018c 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -4957,7 +4957,8 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
>  	 */
>  	intel_crtc_load_lut(crtc);
>  
> -	dev_priv->display.initial_watermarks(intel_crtc->config);
> +	if (dev_priv->display.initial_watermarks != NULL)
> +		dev_priv->display.initial_watermarks(intel_crtc->config);
>  	intel_enable_pipe(intel_crtc);
>  
>  	if (intel_crtc->config->has_pch_encoder)
> @@ -5056,7 +5057,8 @@ static void haswell_crtc_enable(struct drm_crtc *crtc)
>  	if (!intel_crtc->config->has_dsi_encoder)
>  		intel_ddi_enable_transcoder_func(crtc);
>  
> -	dev_priv->display.initial_watermarks(pipe_config);
> +	if (dev_priv->display.initial_watermarks != NULL)
> +		dev_priv->display.initial_watermarks(pipe_config);
>  	intel_enable_pipe(intel_crtc);
>  
>  	if (intel_crtc->config->has_pch_encoder)
> -- 
> 2.5.0
> 

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