From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Cox <alan-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org>
Subject: Re: [RFC 4/4] drm: Add NVIDIA Tegra support
Date: Wed, 11 Apr 2012 16:11:55 +0100
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To: Thierry Reding <thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>
Cc: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Daniel Vetter <daniel-/w4YWyX8dFk@public.gmane.org>, Colin Cross <ccross-z5hGa2qSFaRBDgjK7y7TUQ@public.gmane.org>, Jon Mayo <jmayo-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
List-Id: linux-tegra@vger.kernel.org

> Heh, vmap() is exactly what I do. =) Would you mind explaining why exactly it
> is hideous?

On x86 we don't have a vast amount of address space available for virtual
remappings and the framebuffer then eats over 8MB of it.

The ideal case is that the fb layer can be taught to do page/offset
addressing nicely. At that point we'd be able to attach the text consoles
to arbitary GEM objects.. which means we can do really cool stuff.

Alan