Move the documentation into Documentation/gpu, link it up and pull in
the kernel doc.
No actual text changes except that I did polish the kerneldoc a bit,
especially for vga_client_register().
v2: Remove some rst from vga-switcheroo.rst that I don't understand,
but which seems to be the reason why the new vgaarbiter.rst sometimes
drops out of the sidebar index.
v3: Drop one level of headings and clarify the vgaarb one a bit.
v4: Fix some typos (Sean).
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-20-git-send-email-daniel.vetter@ffwll.ch
vga_set_legacy_decoding() is defined in drivers/gpu/vga/vgaarb.c,
which is only compiled with CONFIG_VGA_ARB. A caller would
therefore get an undefined symbol if the VGA arbiter is not
enabled.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Commit 20cde69402 ("x86, ia64: Move EFI_FB vga_default_device()
initialization to pci_vga_fixup()") moved boot video device detection from
efifb to x86 and ia64 pci/fixup.c.
Remove the left-over #ifndef check that will always match since the
corresponding arch-specific define is gone with above patch.
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Matthew Garrett <matthew.garrett@nebula.com>
This reverts commit 81b5c7bc8d.
Adding drm/i915 into the vga arbiter chain means that X (in a piece of
well-meant paranoia) will do a get/put on the vga decoding around
_every_ accel call down into the ddx. Which results in some nice
performance disasters [1]. This really breaks userspace, by disabling
DRI for everyone, and stops OpenGL from working, this isn't limited
to just the i915 but both the integrated and discrete GPUs on
multi-gpu systems, in other words this causes untold worlds of pain,
Ville tried to come up with a Great Hack to fiddle the required VGA
I/O ops behind everyone's back using stop_machine, but that didn't
really work out [2]. Given that we're fairly late in the -rc stage for
such games let's just revert this all.
One thing we might want to keep is to delay the disabling of the vga
decoding until the fbdev emulation and the fbcon screen is set up. If
we kill vga mem decoding beforehand fbcon can end up with a white
square in the top-left corner it tried to save from the vga memory for
a seamless transition. And we have bug reports on older platforms
which seem to match these symptoms.
But again that's something to play around with in -next.
References: [1] http://lists.x.org/archives/xorg-devel/2013-September/037763.html
References: [2] http://www.spinics.net/lists/intel-gfx/msg34062.html
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is intended to add VGA arbiter support for Intel HD graphics on
Core processors. The old GMCH registers no longer exist, so even
though it appears that i915 participates in VGA arbitration, it doesn't
work. On Intel HD graphics we already attempt to disable VGA regions
of the device. This makes registering as a VGA client unnecessary since
we don't intend to operate differently depending on how many VGA devices
are present. We can disable VGA memory regions by clearing the memory
enable bit in the VGA MSR. That only leaves VGA IO, which we update
the VGA arbiter to know that we don't participate in VGA memory
arbitration. We also add a hook on unload to re-enable memory and
reinstate VGA memory arbitration.
v3: Use explicit LEGACY_IO | LEGACY_MEM when restoring rather than
LEGACY_MASK, per Ville's comments.
v2: I915_READ/WRITE accessors don't work in i915_disable_vga, use inb/outb
directly. Also, on the driver unbind VGA enable path, acquire legacy
IO to re-enable VGA memory. Correct comment.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Add patch changelog. Also squash in a fixup to have a dummy
static inline for vga_set_legacy_decoding for CONFIG_VGA_ARB=n as
reported by the 0-day kernel build bot.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
fixup 2
"Whether" is misspelled in various comments across the tree; this
fixes them. No code changes.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Add some stub functions for the case where CONFIG_VGA_ARB is disabled.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Daniel Vetter writes:
A new drm-intel-next pull. Highlights:
- More gmbus patches from Daniel Kurtz, I think gmbus is now ready, all
known issues fixed.
- Fencing cleanup and pipelined fencing removal from Chris.
- rc6 residency interface from Ben, useful for powertop.
- Cleanups and code reorg around the ringbuffer code (Ben&me).
- Use hw semaphores in the pageflip code from Ben.
- More vlv stuff from Jesse, unfortunately his vlv cpu is doa, so less
merged than I've hoped for - we still have the unused function warning :(
- More hsw patches from Eugeni, again, not yet enabled fully.
- intel_pm.c refactoring from Eugeni.
- Ironlake sprite support from Chris.
- And various smaller improvements/fixes all over the place.
Note that this pull request also contains a backmerge of -rc3 to sort out
a few things in -next. I've also had to frob the shortlog a bit to exclude
anything that -rc3 brings in with this pull.
Regression wise we have a few strange bugs going on, but for all of them
closer inspection revealed that they've been pre-existing, just now
slightly more likely to be hit. And for most of them we have a patch
already. Otherwise QA has not reported any regressions, and I'm also not
aware of anything bad happening in 3.4.
* tag 'drm-intel-next-2012-04-23' of git://people.freedesktop.org/~danvet/drm-intel: (420 commits)
drm/i915: rc6 residency (fix the fix)
drm/i915/tv: fix open-coded ARRAY_SIZE.
drm/i915: invalidate render cache on gen2
drm/i915: Silence the change of LVDS sync polarity
drm/i915: add generic power management initialization
drm/i915: move clock gating functionality into intel_pm module
drm/i915: move emon functionality into intel_pm module
drm/i915: move drps, rps and rc6-related functions to intel_pm
drm/i915: fix line breaks in intel_pm
drm/i915: move watermarks settings into intel_pm module
drm/i915: move fbc-related functionality into intel_pm module
drm/i915: Refactor get_fence() to use the common fence writing routine
drm/i915: Refactor fence clearing to use the common fence writing routine
drm/i915: Refactor put_fence() to use the common fence writing routine
drm/i915: Prepare to consolidate fence writing
drm/i915: Remove the unsightly "optimisation" from flush_fence()
drm/i915: Simplify fence finding
drm/i915: Discard the unused obj->last_fenced_ring
drm/i915: Remove unused ring->setup_seqno
drm/i915: Remove fence pipelining
...
The default VGA device is a somewhat fluid concept on platforms with
multiple GPUs. Add support for setting it so switching code can update
things appropriately, and make sure that the sysfs code returns the right
device if it's changed.
v2: Updated to fix builds when __ARCH_HAS_VGA_DEFAULT_DEVICE is false.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: benh@kernel.crashing.org
Cc: airlied@redhat.com
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fix build warnings by providing a struct stub since no fields of
the struct are used:
include/linux/vgaarb.h:66:9: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:66:9: warning: its scope is only this definition or declaration, which is probably not what you want
include/linux/vgaarb.h:99:34: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:109:6: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:121:8: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:140:37: warning: 'struct pci_dev' declared inside parameter list
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fix link failure without the vga arbitrator.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
We don't actually need this include on any platform.
built on powerpc + x86, reported on m68k.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
vgaarb.h was missing the #define of the #ifndef at the top for the guard
to prevent multiple #include's from causing re-define errors
Signed-off-by: Doug Goldstein <cardoe@gentoo.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Remove reference to vgaarb.c and replace it with a comment about the
arbiter itself.
Reported-by: Tiago Vignatti <tiago.vignatti@nokia.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix some warnings reported in linux-next + also cleanup some
comment errors noticed by Pekka Paalanen.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Background:
Graphic devices are accessed through ranges in I/O or memory space. While most
modern devices allow relocation of such ranges, some "Legacy" VGA devices
implemented on PCI will typically have the same "hard-decoded" addresses as
they did on ISA. For more details see "PCI Bus Binding to IEEE Std 1275-1994
Standard for Boot (Initialization Configuration) Firmware Revision 2.1"
Section 7, Legacy Devices.
The Resource Access Control (RAC) module inside the X server currently does
the task of arbitration when more than one legacy device co-exists on the same
machine. But the problem happens when these devices are trying to be accessed
by different userspace clients (e.g. two server in parallel). Their address
assignments conflict. Therefore an arbitration scheme _outside_ of the X
server is needed to control the sharing of these resources. This document
introduces the operation of the VGA arbiter implemented for Linux kernel.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Tiago Vignatti <tiago.vignatti@nokia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
