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Daniel Vetter
8af6cf88a5
... let's see whether this catches anything earlier and I can track down a few bugs. v2: Add more checks and also add DRM_DEBUG_KMS output so that it's clear which connector/encoder/crtc is being checked atm. Which proved rather useful for debugging ... v3: Add a WARN in the common encoder dpms function, now that also modeset changes properly update the dpms state ... v4: Properly add a short explanation for each WARN, to avoid the need to correlate dmesg lines with source lines accurately. Suggested by Chris Wilson. v5: Also dump (expected, found) for state checks (or wherever it's not apparent from the test what exactly mismatches with expectations). Again suggested by Chris Wilson. v6: Due to an issue reported by Paulo Zanoni I've noticed that the encoder checking is by far not as strict as it could and should be. Improve this. Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
************************************************************
* 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