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Daniel Vetter
0e8ffe1bf8
We need to be able to read out the hw state code for a bunch of reasons: - Correctly disabling boot-up/resume state. - Pure paranoia. Since not all of the pipe configuration is e.g. relevant for fastboot (or at least we can allow some wiggle room in some parameters, like the clocks), we need to add a strict_checking parameter to intel_pipe_config_compare for fastboot. For now intel_pipe_config_compare should be fully paranoid and check everything that the hw state readout code supports. Which for this infrastructure code is nothing. I've gone a bit overboard with adding 3 get_pipe_config functions: The ilk version will differ with the next patch, so it's not too onerous. v2: Don't check the hw config if the pipe is off, since an enabled, but dpms off crtc will obviously have tons of difference with the hw state. Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
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