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path: root/drivers/gpu/drm/i915/intel_dvo.c (follow)
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2012-09-06drm/i915: convert dpms functions of dvo/sdvo/crtDaniel Vetter1-11/+28
Yeah, big patch but I couldn't come up with a neat idea of how to split it up further, that wouldn't break dpms on cloned configs somehow. But the changes in dvo/sdvo/crt are all pretty much orthonogal, so it's not too bad a patch. These are the only encoders that support cloning, which requires a few special changes compared to the previous patches. - Compute the desired state of the display pipe by walking all connected encoders and checking whether any has active connectors. To make this clearer, drop the old mode parameter to the crtc dpms function and rename it to intel_crtc_update_dpms. - There's the curious case of intel_crtc->dpms_mode. With the previous patches to remove the overlay pipe A code and to rework the load detect pipe code, the big users are gone. We still keep it to avoid enabling the pipe twice, but we duplicate this logic with crtc->active, too. Still, leave this for now and just push a fake dpms mode into it that reflects the state of the display pipe. Changes in the encoder dpms functions: - We clamp the dpms state to the supported range right away. This is escpecially important for the VGA outputs, where only older hw supports the intermediate states. This (and the crt->adpa_reg patch) allows us to unify the crt dpms code again between all variants (gmch, vlv and pch). - We only enable/disable the output for dvo/sdvo and leave the encoder running. The encoder will be disabled/enabled when we switch the state of the entire output pipeline (which will happen right away for non-cloned setups). This way the duplication is reduced and strange interaction when disabling output ports at the wrong time avoided. The dpms code for all three types of connectors contains a bit of duplicated logic, but I think keeping these special cases separate is simpler: CRT is the only one that hanldes intermediate dpms state (which requires extra logic to enable/disable things in the right order), and introducing some abstraction just to share the code between dvo and sdvo smells like overkill. We can do that once someone bothers to implement cloning for the more modern outputs. But I doubt that this will ever happen. v2: s/crtc/crt/_set_dpms, noticed by Paulo Zanoni. Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06drm/i915/dvo: convert to encoder disable/enableDaniel Vetter1-2/+30
Similar to the sdvo conversion. Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-17drm/i915: simplify dvo dpms interfaceDaniel Vetter1-2/+2
All dvo drivers only support 2 dpms states, and our dvo driver even switches of the dvo port for anything else than DPMS_ON. Hence ditch this complexity and simply use bool enable. While reading through this code I've noticed that the mode_set function of ch7017 is a bit peculiar - it disable the lvds again, even though the crtc helper code should have done that ... This might be to work around an issue at driver load, we pretty much ignore the hw state when taking over. v2: Also do the conversion for the new ns2501 driver. Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25drm/i915: Support for ns2501-DVOThomas Richter1-1/+9
This patch adds support for the ns2501 DVO, found in some older Fujitsu/Siemens Labtops. It is in the state of "works for me". Includes now proper DPMS support. Includes switching between resolutions - from 640x480 to 1024x768. Currently assumes that the native display resolution is 1024x768. The ns2501 seems to be rather critical - if the output PLL is not running, the chip doesn't seem to be clocked and then doesn't react on i2c messages. Thus, a quick'n-dirty trick ensures that the DVO is active before submitting any i2c messages to it. This is probably to be reviewed. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=17902 Signed-off-by: Thomas Richter <thor@math.tu-berlin.de> [danvet: fixup whitespace fail.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25drm/i915: simplify possible_clones computationDaniel Vetter1-5/+2
Intel hw only has one MUX for encoders, so outputs are either not cloneable or all in the same group of cloneable outputs. This neatly simplifies the code and allows us to ditch some ugly if cascades in the dp and hdmi init code (well, we need these if cascades for other stuff still, but that can be taken care of in follow-up patches). Note that this changes two things: - dvo can now be cloned with sdvo, but dvo is gen2 whereas sdvo is gen3+, so no problem. Note that the old code had a bug and didn't allow cloning crt with dvo (but only the other way round). - sdvo-lvds can now be cloned with sdvo-non-tv. Spec says this won't work, but the only reason I've found is that you can't use the panel-fitter (used for lvds upscaling) with anything else. But we don't use the panel fitter for sdvo-lvds. Imo this part of Bspec is a) rather confusing b) mostly as a guideline to implementors (i.e. explicitly stating what is already implicit from the spec, without always going into the details of why). So I think we can ignore this - worst case we'll get a bug report from a user with with sdvo-lvds and sdvo-tmds and have to add that special case back in. Because sdvo lvds is a bit special explain in comments why sdvo LVDS outputs can be cloned, but native LVDS and eDP can't be cloned - we use the panel fitter for the later, but not for sdvo. Note that this also uncoditionally initializes the panel_vdd work used by eDP. Trying to be clever doesn't buy us anything (but strange bugs) and this way we can kill the is_edp check. v2: Incorporate review from Paulo - Add in a missing space. - Pimp comment message to address his concerns. Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-19drm: Make the .mode_fixup() operations mode argument a const pointerLaurent Pinchart1-1/+1
The passed mode must not be modified by the operation, make it const. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-03-28drm/i915/intel_i2c: refactor using intel_gmbus_get_adapterDaniel Kurtz1-3/+3
Instead of letting other modules directly access the ->gmbus array, introduce intel_gmbus_get_adapter() for looking up an i2c_adapter for a given gmbus port identifier. This will enable later refactoring of the gmbus port list. Note: Before requesting an adapter for a given gmbus port number, the driver must first check its validity using i2c_intel_gmbus_is_port_valid(). If this check fails, a call to intel_gmbus_get_adapter() will WARN_ON and return NULL. This is relevant for parts of the driver that read a port from VBIOS, which might be improperly initialized and contain an invalid port. In these cases, the driver must fall back to using a safer default port. Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-02-10drm/i915: fixup interlaced vertical timings confusion, part 1Daniel Vetter1-1/+0
We have a pretty decent confusion about vertical timings of interlaced modes. Peter Ross has written a patch that makes interlace modes work on a lot more platforms/output combinations by doubling the vertical timings. The issue with that patch is that core drm _does_ support specifying whether we want these vertical timings in fields or frames, we just haven't managed to consistently use this facility. The relavant function is drm_mode_set_crtcinfo, which fills in the crtc timing information. The first thing to note is that the drm core keeps interlaced modes in frames, but displays modelines in fields. So when the crtc modeset helper copies over the mode into adjusted_mode it will already contain vertical timings in half-frames. The result is that the fixup code in intel_crtc_mode_fixup doesn't actually do anything (in most cases at least). Now gen3+ natively supports interlaced modes and wants the vertical timings in frames. Which is what sdvo already fixes up, at least under some conditions. There are a few other place that demand vertical timings in fields but never actually deal with interlaced modes, so use frame timings for consistency, too. These are: - lvds panel, - dvo encoders - dvo is the only way gen2 could support interlaced mode, but currently we don't support any encoders that do. - tv out - despite that the tv dac sends out an interlaced signal it expects a progressive mode pipe configuration. All these encoders enforce progressive modes by resetting interlace_allowed. Hence we always want crtc vertical timings in frames. Enforce this in our crtc mode_fixup function and rip out any redudant timing computations from the encoders' mode_fixup function. v2-4: Adjust the vertical timings a bit. v5: Split out the 'subtract-one for interlaced' fixes. v6: Clarify issues around tv-out and gen2. Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com> Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Tested-by: Christopher Egert <cme3000@gmail.com> Tested-by: Alfonso Fiore <alfonso.fiore@gmail.com> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2011-02-07drm/i915: cleanup per-pipe reg usageJesse Barnes1-1/+1
We had some conversions over to the _PIPE macros, but didn't get everything. So hide the per-pipe regs with an _ (still used in a few places for legacy) and add a few _PIPE based macros, then make sure everyone uses them. [update: remove usage of non-existent no-op macro] [update 2: keep modesetting suspend/resume code, update to new reg names] Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> [ickle: stylistic cleanups for checkpatch and taste] Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-28drm/i915/dvo: Fix panel and DDC i2c pinsChris Wilson1-9/+3
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-21drm/i915: Use the correct DPB GMBUS port for GPIOEChris Wilson1-2/+2
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-21Merge branch 'drm-intel-fixes' into HEADChris Wilson1-1/+2
Conflicts: drivers/char/agp/intel-agp.c drivers/gpu/drm/i915/intel_crt.c
2010-09-18drm/i915: use GMBUS to manage i2c linksChris Wilson1-21/+12
Use the GMBUS interface rather than direct bit banging to grab the EDID over DDC (and for other forms of auxiliary communication with external display controllers). The hope is that this method will be much faster and more reliable than bit banging for fetching EDIDs from buggy monitors or through switches, though we still preserve the bit banging as a fallback in case GMBUS fails. Based on an original patch by Jesse Barnes. Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-15drm/i915: call drm_encoder_init firstChris Wilson1-2/+3
Later initialisation of the encoder often requires that drm_encoder_init() has already been called, for instance, initialiasing the DDC buses. Yet another recent regression, as 819f3fb7 depended upon these fixes which I missed when cherry-picking. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-14drm/i915/i2c: Track the parent encoder rather than just the devChris Wilson1-4/+5
The SDVO proxy i2c adapter wants to be able to use information stored in the encoder, so pass that through intel_i2c rather than iterate over all known encoders every time. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-09-14drm: Use a nondestructive mode for output detect when polling (v2)Chris Wilson1-2/+1
v2: Julien Cristau pointed out that @nondestructive results in double-negatives and confusion when trying to interpret the parameter, so use @force instead. Much easier to type as well. ;-) And fix the miscompilation of vmgfx reported by Sedat Dilek. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-13drm: Use a nondestructive mode for output detect when pollingChris Wilson1-1/+3
Destructive load-detection is very expensive and due to failings elsewhere can trigger system wide stalls of up to 600ms. A simple first step to correcting this is not to invoke such an expensive and destructive load-detection operation automatically. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29536 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16265 Reported-by: Bruno Prémont <bonbons@linux-vserver.org> Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-09drm/i915: Make the connector->encoder relationship explicitChris Wilson1-12/+12
Currently we have a exact mapping of a connector onto an encoder for its whole lifetime. Make this an explicit property of the structure and so simplify the code. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-09-09drm/i915: Use the direct mapping of pipe->crtcChris Wilson1-1/+1
Why iterate all the crtcs to find the pipe, when we already know which crtc is attached to which pipe? Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-09-09drm/i915: Rename intel_encoder->enc to base for consistencyChris Wilson1-4/+4
[Patch is slightly larger than is strictly necessary to fixup surrounding checkpatch.pl errors.] Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-09drm/i915: Subclass intel_encoder.Chris Wilson1-71/+65
Subclass intel_encoder to reduce the pointer dance through intel_encoder->dev_priv. 10 files changed, 896 insertions(+), 997 deletions(-) Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
2010-04-20Merge remote branch 'anholt/drm-intel-next' of /home/airlied/kernel/drm-next into drm-core-nextDave Airlie1-68/+35
* 'anholt/drm-intel-next' of /home/airlied/kernel/drm-next: (48 commits) agp/intel-gtt: kill previous_size assignments agp/intel-gtt: kill intel_i830_tlbflush agp/intel: split out gmch/gtt probe, part 1 agp/intel: kill mutli_gmch_chip agp/intel: uncoditionally reconfigure driver on resume agp/intel: split out the GTT support agp/intel: introduce intel-agp.h header file drm/i915: Don't touch PORT_HOTPLUG_EN in intel_dp_detect() drm/i915/pch: Use minimal number of FDI lanes (v2) drm/i915: Add the support of memory self-refresh on Ironlake drm/i915: Move Pineview CxSR and watermark code into update_wm hook. drm/i915: Only save/restore FBC on the platform that supports FBC drm/i915: Fix the incorrect argument for SDVO SET_TV_format command drm/i915: Add support of SDVO on Ibexpeak PCH drm/i915: Don't enable pipe/plane/VCO early (wait for DPMS on). drm/i915: do not read uninitialized ->dev_private Revert "drm/i915: Use a dmi quirk to skip a broken SDVO TV output." drm/i915: implement multifunction SDVO device support drm/i915: remove unused intel_pipe_get_connector() drm/i915: remove connector object in old output structure ...
2010-04-17Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intelLinus Torvalds1-46/+46
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: drm/i915: Ignore LVDS EDID when it is unavailabe or invalid drm/i915: Add no_lvds entry for the Clientron U800 drm/i915: Rename many remaining uses of "output" to encoder or connector. drm/i915: Rename intel_output to intel_encoder. agp/intel: intel_845_driver is an agp driver! drm/i915: introduce to_intel_bo helper drm/i915: Disable FBC on 915GM and 945GM.
2010-04-12drm/i915: convert DVO driver to new encoder/connector structureZhenyu Wang1-36/+34
Also remove old UMS copied code for get_crtc. Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
2010-04-12drm/i915: Remove dead KMS encoder save/restore code.Eric Anholt1-31/+0
This was brought over from UMS, and used for a while until we decided that drm_helper_resume_force_mode was easier and more reliable, since it didn't require duplicating all the code deleted here. We just forgot to delete all that junk for a while.
2010-04-09drm/i915: change intel_ddc_get_modes() function parametersZhenyu Wang1-1/+1
This one replaces original param for intel_ddc_get_modes() with DRM connector and i2c bus adapter instead. With explicit params, we won't require that a single driver structure must hold connector and DDC bus reference, which ease the conversion to splitted encoder/ connector model. It also clears up for some cases that we would steal other DDC bus for mode probe, like VGA analog DDC probe for DVI-I. Also it fixed a bug in old DVI-I probe handling, that failed to restore origin analog GPIO port. Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.hTejun Heo1-0/+1
percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-25drm/i915: Rename intel_output to intel_encoder.Eric Anholt1-46/+46
The intel_output naming is inherited from the UMS code, which had a structure of screen -> CRTC -> output. The DRM code has an additional notion of encoder/connector, so the structure is screen -> CRTC -> encoder -> connector. This is a useful structure for SDVO encoders which can support multiple connectors (each of which requires different programming in the one encoder and could be connected to different CRTCs), or for DVI-I, where multiple encoders feed into the connector for whether it's used for digital or analog. Most of our code is encoder-related, so transition it to talking about encoders before we start trying to distinguish connectors. This patch is produced by sed s/intel_output/intel_encoder/ over the driver. Signed-off-by: Eric Anholt <eric@anholt.net>
2009-08-24drm/i915: Set crtc/clone mask in different output devicesMa Ling1-0/+6
Based on Bspec each encoder has different sharing pipe property, i.e. Integrated or SDVO TV both will occupy one pipe exclusively, and sdvo-non-tv and crt are allowed to share one. The patch moves sharing judgment into differnet output functions, and sets the right clone bit. This fixes both HDMI outputs choosing the same pipe. https://bugs.freedesktop.org/show_bug.cgi?id=22247 Signed-off-by: Ma Ling <ling.ma@intel.com> Reviewed-by : Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
2009-06-18drm/i915: Change I2C api to pass around i2c_adaptersKeith Packard1-10/+6
The existing API passed around intel_i2c_chan pointers, which are dependent on the i2c bit-banging algo. This precluded the driver from using outputs which use a different algo. Switching to the more general i2c_adpater allows the driver to support non bit-banging DDC. This also required moving the slave address into the output private structures. Signed-off-by: Keith Packard <keithp@keithp.com>
2009-06-04drm: Hook up DPMS property handling in drm_crtc.c. Add drm_helper_connector_dpms.Keith Packard1-0/+1
Making the drm_crtc.c code recognize the DPMS property and invoke the connector->dpms function doesn't remove any capability from the driver while reducing code duplication. That just highlighted the problem with the existing DPMS functions which could turn off the connector, but failed to turn off any relevant crtcs. The new drm_helper_connector_dpms function manages all of that, using the drm_helper-specific crtc and encoder dpms functions, automatically computing the appropriate DPMS level for each object in the system. This fixes the current troubles in the i915 driver which left PLLs, pipes and planes running while in DPMS_OFF mode or even while they were unused. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-12-29drm/i915: fix sparse warnings: move 'extern' decls to header fileHannes Eder1-6/+0
Move 'extern'-decls from "intel_dvo.c" to "dvo.h", as "dvo.h" is included by and only by files where the symbols are either defined or used. Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Eric Anholt <eric@anholt.net> Signed-off-by: Dave Airlie <airlied@linux.ie>
2008-12-29drm/i915: fix sparse warnings: make symbols staticHannes Eder1-2/+2
Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Eric Anholt <eric@anholt.net> Signed-off-by: Dave Airlie <airlied@linux.ie>
2008-12-29DRM: i915: add mode setting supportJesse Barnes1-0/+501
This commit adds i915 driver support for the DRM mode setting APIs. Currently, VGA, LVDS, SDVO DVI & VGA, TV and DVO LVDS outputs are supported. HDMI, DisplayPort and additional SDVO output support will follow. Support for the mode setting code is controlled by the new 'modeset' module option. A new config option, CONFIG_DRM_I915_KMS controls the default behavior, and whether a PCI ID list is built into the module for use by user level module utilities. Note that if mode setting is enabled, user level drivers that access display registers directly or that don't use the kernel graphics memory manager will likely corrupt kernel graphics memory, disrupt output configuration (possibly leading to hangs and/or blank displays), and prevent panic/oops messages from appearing. So use caution when enabling this code; be sure your user level code supports the new interfaces. A new SysRq key, 'g', provides emergency support for switching back to the kernel's framebuffer console; which is useful for testing. Co-authors: Dave Airlie <airlied@linux.ie>, Hong Liu <hong.liu@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Eric Anholt <eric@anholt.net> Signed-off-by: Dave Airlie <airlied@redhat.com>