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Pradeep Bhat
83a7280ebc
This patch reads the DRRS support and Mode type from VBT fields. The read information will be stored in VBT struct during BIOS parsing. The above functionality is needed for decision making whether DRRS feature is supported in i915 driver for eDP panels. This information helps us decide if seamless DRRS can be done at runtime to support certain power saving features. This patch was tested by setting necessary bit in VBT struct and merging the new VBT with system BIOS so that we can read the value. v2: Incorporated review comments from Chris Wilson Removed "intel_" as a prefix for DRRS specific declarations. v3: Incorporated Jani's review comments Removed function which deducts drrs mode from panel_type. Modified some print statements. Made changes to use DRRS_NOT_SUPPORTED as 0 instead of -1. v4: Incorporated Jani's review comments. Modifications around setting vbt drrs_type. Signed-off-by: Pradeep Bhat <pradeep.bhat@intel.com> Signed-off-by: Vandana Kannan <vandana.kannan@intel.com> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Jani Nikula <jani.nikula@linux.intel.com> [danvet: Drop the misleading/redundant comment about the added drrs field in the vbt struct as discussed with Jani on irc.] Reviewed-by: Jani Nikula <jani.nikula@intel.com> 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/ *
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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