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Yuanhan Liu
1398261a2e
Add the support of memory self-refresh on Sandybridge, which is now support 3 levels of watermarks and the source of the latency values for watermarks has changed. On Sandybridge, the LP0 WM value is not hardcoded any more. All the latency value is now should be extracted from MCHBAR SSKPD register. And the MCHBAR base address is changed, too. For the WM values, if any calculated watermark values is larger than the maximum value that can be programmed into the associated watermark register, that watermark must be disabled. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> [ickle: remove duplicate compute routines and fixup for checkpatch] Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
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* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
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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://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html