schedule(), io_schedule() and schedule_timeout() always return
with TASK_RUNNING state set, so one more setting is unnecessary.

(All places in patch are visible good, only exception is
 kiblnd_scheduler() from:

      drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c

 Its schedule() is one line above standard 3 lines of unified diff)

No places where set_current_state() is used for mb().
Signed-off-by: NKirill Tkhai <ktkhai@parallels.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1410529254.3569.23.camel@tkhai
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Anil Belur <askb23@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: David Howells <dhowells@redhat.com>
Cc: Dmitry Eremin <dmitry.eremin@intel.com>
Cc: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Isaac Huang <he.huang@intel.com>
Cc: James E.J. Bottomley <JBottomley@parallels.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Liang Zhen <liang.zhen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masaru Nomura <massa.nomura@gmail.com>
Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Oleg Drokin <green@linuxhacker.ru>
Cc: Peng Tao <bergwolf@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Ursula Braun <ursula.braun@de.ibm.com>
Cc: Zi Shen Lim <zlim.lnx@gmail.com>
Cc: devel@driverdev.osuosl.org
Cc: dm-devel@redhat.com
Cc: dri-devel@lists.freedesktop.org
Cc: fcoe-devel@open-fcoe.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-afs@lists.infradead.org
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-nfs@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: qla2xxx-upstream@qlogic.com
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: user-mode-linux-user@lists.sourceforge.net
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Drivers should call this on unload to unregister pmops.

Bug:
https://bugzilla.kernel.org/show_bug.cgi?id=84431Reviewed-by: NBen Skeggs <bskeggs@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>

Commit 20cde694 ("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: NBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Matthew Garrett <matthew.garrett@nebula.com>

Commit 20cde694 ("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.

For dual-GPU Apple computers above change represents a regression as code
in efifb did forcefully override vga_default_device while the merge did not
(vgaarb happens prior to PCI fixup).

To improve on initial device selection by vgaarb (it cannot know if PCI
device not behind bridges see/decode legacy VGA I/O or not), move the
screen_info based check from pci_video_fixup() to vgaarb's init function and
use it to refine/override decision taken while adding the individual PCI
VGA devices.  This way PCI fixup has no reason to adjust vga_default_device
anymore but can depend on its value for flagging shadowed VBIOS.

This has the nice benefit of removing duplicated code but does introduce a
#if defined() block in vgaarb.  Not all architectures have screen_info and
would cause compile to fail without it.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=84461Reported-and-Tested-By: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Matthew Garrett <matthew.garrett@nebula.com>
CC: stable@vger.kernel.org # v3.5+

The VGA arbiter does not allow devices to "own" resources that it
doesn't "decode".  However, it does allow devices to "lock" resources
that it doesn't decode.  This gets us into trouble because locking
the resource goes through the same bridge routing updates regardless
of whether we decode the resource.  This means that when a non-decoded
resource is released, the bridge is left with VGA routing enabled and
locking a different device won't clear it.

This happens in the following scenario:

VGA device 01:00.0 (VGA1) is owned by the radeon driver, which
registers a set_vga_decode function which releases legacy VGA decodes.

VGA device 02:00.0 (VGA2) is any VGA device.

VGA1 user locks VGA resources triggering first_use callback of
set_vga_decoded, clearing "decode" and "owns" of legacy resources
on VGA1.

VGA1 user unlocks VGA resources.

VGA2 user locks VGA resources, which skips VGA1 as conflicting as it
does not "own" legacy resources, although VGA routing is still enabled
for the VGA1 bridge.  VGA routing is enabled on VGA2 bridge.

VGA2 may or may not receive VGA transactions depending on the bus
priority of VGA1 vs VGA2 bridge.

To resolve this, we need to allow devices to "own" resources that they
do not "decode".  This way we can track bus ownership of VGA.  When a
device decodes VGA, it only means that we must update the command bits
in cases where the conflicting device is on the same bus.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Avoids blank screens on muxed systems when runpm is active.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=75917Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

When VGA decodes change we need to do a bit more evaluation of exactly what
has changed.  We don't necessarily give up all the old owns resources and
we need to account for resources with locks.  The new algorithm is: If
something is added, update decodes.  If legacy resources were added and
none were there before, we have a new participant.  If something is
removed, update decodes.  If we previously owned it, we no longer own it.
If it was previously locked, invalidate all locks and release it.  If
legacy resources were removed and none are left, remove the participant
from VGA arbitration.

Previously we updated decodes, released ownership of everything that was
previously decoded, ignored all locks, and went off looking for another
device to transfer VGA to.  In a test case where Intel IGD removes only
legacy VGA memory decoding, this left the arbiter switching to discrete
graphics without actually disabling legacy VGA IO from the IGD.  As a
bonus, we bumped up the count of VGA arbitration participants for no
good reason.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: Dave Airlie <airlied@redhat.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Kill now unused variables, reported by the 0-day kernel
builtbot.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If a device does not own a resource then we don't need to disable it.
This resolves the case where an Intel IGD device can be configured to
disable decode of VGA memory but we still need the arbiter to handle
VGA I/O port routing.  When the IGD device is in conflict, only
PCI_COMMAND_IO should be disabled since VGA memory does not require
arbitration on this device.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: Dave Airlie <airlied@redhat.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For optimus and powerxpress muxless we really want the GPU
driver deciding when to power up/down the GPU, not userspace.

This adds the ability for a driver to dynamically power up/down
the GPU and remove the switcheroo from controlling it, the
switcheroo reports the dynamic state to userspace also.

It also adds 2 power domains, one for machine where the power
switch is controlled outside the GPU D3 state, so the powerdown
ordering is done correctly, and the second for the hdmi audio
device to make sure it can resume for PCI config space accesses.

v1.1: fix build with switcheroo off

v2: add power domain support for radeon and v1 nvidia dsms
v2.1: fix typo in off case

v3: add audio power domain for hdmi audio + misc audio fixes

v4: use PCI_SLOT macro, drop power reference on hdmi audio resume
failure also.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Okay so Alan's patch handled the case where there was no registered fbcon,
however the other path entered in set_con2fb_map pit.

In there we called fbcon_takeover, but we also took the console lock in a couple
of places. So push the console lock out to the callers of set_con2fb_map,

this means fbmem and switcheroo needed to take the lock around the fb notifier
entry points that lead to this.

This should fix the efifb regression seen by Maarten.
Tested-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: NLu Hua <huax.lu@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: NIgor Murzov <e-mail@date.by>
Signed-off-by: NDave Airlie <airlied@redhat.com>

when __ARCH_HAS_VGA_DEFAULT_DEVICE is not defined, aka EFIFB is not used,
for static path, vga_default setting is through vga_arbiter_add_pci_device.
and later x86 pci_fixup_video, will skip setting again.
- subsys_initcall(vga_arb_device_init) come first to call
vga_arbiter_add_pci_device. It will call pci_get_dev to hold one reference.

for hotplug add path, even vga_arbiter_add_pci_device is called via
notifier, but it will check VGA_RSRC_LEGACY_MASK that is not set for
hotplug path.  So x86 pci_fixup_video will take over to call
vga_set_default_device().  It will not hold one refrence.

Later for hotplug remove path, vga_arbiter_del_pci_device that does not
check VGA_RSRC_LEGACY_MASK will call put_device and it will cause ref_count
to decrease extra. that will have that pci device get deleted early
wrongly.

Need to make get/put balance for both cases.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: x86@kernel.org
Cc: Dave Airlie <airlied@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Julia Lawall <julia@diku.dk>
Cc: Matthew Garrett <mjg@redhat.com>

Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.

    struct pci_bus *pci_bus = pci_find_bus(domain, busno);
    struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

This callback is a no-op in nouveau, and the upcoming apple-gmux
switcheroo support won't require it either. Rather than forcing drivers
to stub it out, just make it optional and remove the callback from
nouveau.
Signed-off-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

vga_switcheroo assumes that the handler will be registered before the
last client, otherwise switching will not be enabled. Likewise it's
assumed that the handler will not be unregistered without at least one
client also being unregistered, otherwise switching will remain enabled
despite no longer having a handler. These assumptions cannot be enforced
if the handler is in a separate driver from both clients, as with the
gmux found in Apple laptops. Remove this assumption.
Signed-off-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

The audio clients have to be disabled before disabling the VGA and
switching.  Similarly, enabling the audio client should be done at
last.  Otherwise the audio-side operation stalls, eventually leading
to Oops or lockups.
Tested-by: NJörg-Volker Peetz <jvpeetz@web.de>
Acked-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Add vga_switcheroo_get_client_state() to get the current state of the
client.  This is necessary to determine the proper initial state of
audio clients in HD-audio driver.
Acked-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Add the support for audio clients to VGA-switcheroo for handling the
HDMI audio controller together with VGA switching.  The id of the
audio controller should be given explicitly at registration time
unlike the video controller.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43155Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This changes the API as a clean-up.  Instead of passing multiple
function pointers at each time, introduce a new struct holding the
whole callback functions and pass it to the registration.

The same struct will be used for the upcoming audio client
registration, too.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Refactor the code base a bit for the further work to adapt more clients.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This fixes the build breakage reported by Stephen in -next
when merging the drm-next tree.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Since Matthew's changes we have to select arbitration.

Reported-by: devh on #radeon
Signed-off-by: NDave Airlie <airlied@redhat.com>

vga-switcheroo currently changes the default VGA device by fiddling with
the IORESOURCE_ROM_SHADOW flag on the device. This isn't strictly accurate,
since there's no guarantee that switching also changes the ROM decoding.
Switch over to using the vgaarb functions for this.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

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: NMatthew Garrett <mjg@redhat.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Acked-by: benh@kernel.crashing.org
Cc: airlied@redhat.com
Signed-off-by: NDave Airlie <airlied@redhat.com>

kbuf is a buffer that is local to this function, so all of the error paths
leaving the function should release it.
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

I assumed all PCI buses had a bridge, but playing with qemu recently, I
discovered vgaarb bug where it wasn't detecting both devices shared a bridge
at the root level.

Don't check for NULL, if two buses have a NULL bridge, assume they share the
root bus.
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NRakib Mullick <rakib.mullick@gmail.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the requested device is already active, ignore the request.

This restores the original behaviour of the interface. The change was
probably an unintended side effect of

commit 66b37c67 vga_switcheroo: split switching into two stages

which did not take into account to duplicate the !active check in the split-off
stage2.

Fix this by factoring that check out of stage1 into the debugfs_write routine.

References: https://bugzilla.kernel.org/show_bug.cgi?id=34252Reported-by: NIgor Murzov <e-mail@date.by>
Tested-by: NIgor Murzov <e-mail@date.by>
Signed-off-by: NFlorian Mickler <florian@mickler.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This is unbalanced and probably more fitting for the client
to take care of.  Remove it.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

So in a lot of modern systems, a GPU will always be below a parent bridge that won't share with any other GPUs. This means VGA arbitration on those GPUs can be controlled by using the bridge routing instead of io/mem decodes.

The problem is locating which GPUs share which upstream bridges. This patch attempts to identify all the GPUs which can be controlled via bridges, and ones that can't. This patch endeavours to work out the bridge sharing semantics.

When disabling GPUs via a bridge, it doesn't do irq callbacks or touch the io/mem decodes for the gpu.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Starting with SandyBridge (though possible with earlier hacked BIOSes),
the BIOS may initialise the IGFX as secondary to a discrete GPU. Prior,
it would simply disable the integrated GPU. So we adjust our PCI class
mask to match any DISPLAY_CLASS device.

In such a configuration, the IGFX is not a primary VGA controller and
so should not take part in VGA arbitration, and the error return from
vga_client_register() is expected.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NDavid Woodhouse <david.woodhouse@intel.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is a copy-and-paste bug.  We should be comparing 4 characters here
instead of 3.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

stage 1: turn card on, switch boot vga pointer.
stage 2: switch fbs, switch mux and power off old card.
Signed-off-by: NDave Airlie <airlied@redhat.com>

This adds a hook after the mux is switched for the driver to reprobe
the connected outputs.
Signed-off-by: NDave Airlie <airlied@redhat.com>

This allows the mux to be switched from userspace using MIGD/MDIS
command to the switch.
Signed-off-by: NDave Airlie <airlied@redhat.com>

At least on the nvidia mux the power switch seems to be executed
by the ACPI PS0/PS3 methods so need to do it explicitly.
Signed-off-by: NDave Airlie <airlied@redhat.com>

We really want to see this so we can confirm that we pick the right one.
Signed-off-by: NDave Airlie <airlied@redhat.com>