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d2f5935770
Migration helper. The i915 driver recently added a 'depends on FB' rule to its Kconfig entry - which silently turns off DRM_I915 if someone has a working config but no CONFIG_FB selected, and upgrades to the latest upstream kernel. Norbert Preining reported this problem: Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12599 Subject : dri /dev node disappeared with 2.6.29-rc1 So change it to "select FB", which auto-selects framebuffer support. This way the driver keeps working, regardless of whether FB was enabled before or not. Kconfig select's of interactive options can be problematic to dependencies and can cause build breakages - but in this case it's safe because it's a leaf entry with no dependencies of its own. ( There is some minor circular dependency fallout as FB_I810 and FB_INTEL also used 'depends on FB' constructs - update those to "select FB" too. ) Reported-by: Norbert Preining <preining@logic.at> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dave Airlie <airlied@linux.ie>
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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