This reverts the series of commits
67dbb4ea33281ab031a847807ce381
that changed the GART VM start offset. It fixed some machines, but
seems to continually interact badly with some X versions.
Quoth Ben Herrenschmidt:
"So I think at this point, the best is that we keep the old bogus code
that at least is consistent with the bug in the server. I'm working on a
big patch to X that reworks the memory map stuff completely and fixes
those issues on the server side, I'll do a DRM patch matching this X fix
as well so that the memory map is only ever set in one place and with
what I hope is a correct algorithm..."
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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* For the very latest on DRI development, please see: *
* http://dri.sourceforge.net/ *
************************************************************
The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://precisioninsight.com/piinsights.html
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://precisioninsight.com/dr/drm.html
Hardware Locking for the Direct Rendering Infrastructure
http://precisioninsight.com/dr/locking.html
A Security Analysis of the Direct Rendering Infrastructure
http://precisioninsight.com/dr/security.html
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.sourceforge.net/ *
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