Re: [PATCH 1/2] drm/i915: split page flip queueing into per-chipset functions

From: Chris Wilson <chris@chris-wilson.co.uk>
To: Jesse Barnes <jbarnes@virtuousgeek.org>, intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH 1/2] drm/i915: split page flip queueing into per-chipset functions
Date: Tue, 14 Jun 2011 19:20:12 +0100	[thread overview]
Message-ID: <f80fcd$h9mqf@fmsmga001.fm.intel.com> (raw)
In-Reply-To: <1308075188-2821-1-git-send-email-jbarnes@virtuousgeek.org>

On Tue, 14 Jun 2011 11:13:07 -0700, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> @@ -6343,7 +6458,12 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
>  	/* Offset into the new buffer for cases of shared fbs between CRTCs */
>  	offset = crtc->y * fb->pitch + crtc->x * fb->bits_per_pixel/8;
>  
> -	ret = BEGIN_LP_RING(4);
> +	if (!dev_priv->display.queue_flip) {
> +		ret = -ENODEV;
> +		goto cleanup_objs;
> +	}
> +
> +	ret = dev_priv->display.queue_flip(dev, crtc, fb, obj);

Neil Brown would recommend that we use a default queue_flip that returns
-ENODEV which both removes lines of code from this complicated routine
and optimises the common case. I agree with him. :)
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre