Files
linux-apfs/drivers/gpu/drm
Jani Nikula f30d26e468 drm/i915/eDP: do not write power sequence registers for ghost eDP
Some machines detect an eDP port even if it's not really there, and eDP
initialization has a fail path for this. Typically such machines have an
LVDS display instead. A regression introduced in

commit 82ed61fa1a
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sat Oct 20 20:57:41 2012 +0200

    drm/i915: make edp panel power sequence setup more robust

updated the power sequence registers PCH_PP_ON_DELAYS, PCH_PP_OFF_DELAYS,
and PCH_PP_DIVISOR also in the ghost eDP case, messing up the LVDS display.

Split the power sequencer initialization into two, delaying the register
updates until after we know the eDP is real.

Note: Keep the PP_CONTROL unlocking in the first part, even if it does not
update registers, per the commit message of the above mentioned commit.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=52601
Reported-and-tested-by: Ryan Coe <ryan@rycomotorsports.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-16 10:23:01 +01:00
..
2012-12-10 20:21:30 +10:00
2012-12-15 02:40:00 +09:00
2012-11-28 18:36:05 +10:00

************************************************************
* 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