From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: Flicker-free boot in DRM
Date: Sat, 29 Oct 2011 09:12:13 +0100
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On Sat, 29 Oct 2011 00:05:22 -0700, "Keith Packard" <keithp@keithp.com> wrote:
>  *  Constructing a fake drm_framebuffer is a pain; there are a million
>     places that assume all kinds of things about the frame buffer on
>     a crtc.

This is vital as we need to capture the current GATT and stolen allocations
and preserve them across takeover. Otherwise we end up using the VBIOS
scanout PTEs as our ringbuffer and the actual memory for FBC.

Best case failure is garbage during takeover; worst case is a GPU hang.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre