[Intel-gfx] [PATCH 2/2] drm/i915: Recompute WM when the cursor size changes

[Damien Lespiau]

On Wed, Mar 26, 2014 at 12:38:15PM +0000, Chris Wilson wrote:
> If the cursor width is changed, we may need to recompute our WM to
> prevent untold flickering. We hope that the registers are flushed on the
> same vblank to prevent underruns...
> 
> Cc: Damien Lespiau <damien.lespiau at intel.com>
> Cc: Sagar Kamble <sagar.a.kamble at intel.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Indeed, I'll learn to see the bigger picture one day, one day...

Reviewed-by: Damien Lespiau <damien.lespiau at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_display.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index c8c52d105b8c..e15b3abe1350 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -7763,6 +7763,7 @@ static int intel_crtc_cursor_set(struct drm_crtc *crtc,
>  	struct drm_i915_private *dev_priv = dev->dev_private;
>  	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
>  	struct drm_i915_gem_object *obj;
> +	unsigned old_width;
>  	uint32_t addr;
>  	int ret;
>  
> @@ -7853,13 +7854,18 @@ static int intel_crtc_cursor_set(struct drm_crtc *crtc,
>  
>  	mutex_unlock(&dev->struct_mutex);
>  
> +	old_width = intel_crtc->cursor_width;
> +
>  	intel_crtc->cursor_addr = addr;
>  	intel_crtc->cursor_bo = obj;
>  	intel_crtc->cursor_width = width;
>  	intel_crtc->cursor_height = height;
>  
> -	if (intel_crtc->active)
> +	if (intel_crtc->active) {
> +		if (old_width != width)
> +			intel_update_watermarks(crtc);
>  		intel_crtc_update_cursor(crtc, intel_crtc->cursor_bo != NULL);
> +	}
>  
>  	return 0;
>  fail_unpin:
> -- 
> 1.9.1
>