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: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to the sdvo conversion.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to crt, this doesn't convert the dpms functions.
Also similar to crt, we don't switch of the display pipe
for the intermediate modes, only DPMS_OFF is truely off.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

CRT is the first output which can be cloned, hence we cannot (yet)
move the dpms handling over to disable/enable. This requires some more
smarts in intel_crtc_dpms first to set the display pipe status
depening upon encoder->connectors_active of all connected encoders.

Because that will happen in a separate step, don't touch the dpms
functions, yet.

v2: Be careful about clearing the _DISABLE flags for intermediate dpms
modes - otherwise we might clobber the crt state when another (cloned)
connector gets enabled.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

DP is the first encoder which isn't simple. As

commit d240f20f
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Fri Aug 13 15:43:26 2010 -0700

    drm/i915: make sure eDP PLL is enabled at the right time

discovered, we need to enable the eDP PLL for the cpu port _before_ we
enable the pipes and planes. After a few more commits the current
solution is to enable the PLL in the dp mode_set function (because
this is the only encoder callback the crtc helper code calls before it
calls the crtc's commit function).

Now I suspect that we actually should enable/disable the entire cpu
eDP port before/after planes, but thanks to how the crtc helper code
assumes that you can disable an encoder without disabling it's crtc
right away, this won't work.

The result is that the current prepare/commit hooks don't touch the
eDP PLL, but instead it get's frobbed in dp_mode_set and in the dp
dpms function. Hence we need to keep things (at least for now)
bug-for-bug compatible by using our own special dp dpms function and
keep everything else more-or-less as-is (just using our own
infrastrucutre now).

This mess can only be cleaned up once we control the entire modeset
sequence and can move things around freely.

v2: Squash unsupported dpms modes to OFF at the beginning of the DP
dpms function.

v3: Need to set the dpms state to off in dp_disable, otherwise this
breaks the newly added WARNs ...

v4: Rebased against edp panel off sequence changes in 3.6-rc2
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With the previous patch LVDS is also a simple case. Treat it
accordingly.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Like hdmi tv outputs are simple: They only have 2 states and can't be
cloned. Hence give it the same treatment.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I've picked hdmi as the first encoder to convert because it's rather
simple:
- no cloning possible
- no differences between prepare/commit and dpms off/on switching.

A few changes are required to do so:
- Split up the dpms code into an enable/disable function and wire it
  up with the intel encoder.
- Noop out the existing encoder prepare/commit functions used by the
  crtc helper - our crtc enable/disable code now calls back into the
  encoder enable/disable code at the right spot.
- Create new helper functions to handle dpms changes.
- Add intel_encoder->connectors_active to better track dpms state. Atm
  this is unused, but it will be useful to correctly disable the
  entire display pipe for cloned configurations. Also note that for
  now this is only useful in the dpms code - thanks to the crtc
  helper's dpms confusion across a modeset operation we can't (yet)
  rely on this having a sensible value in all circumstances.
- Rip out the encoder helper dpms callback, if this is still getting
  called somewhere we have a bug. The slight issue with that is that
  the crtc helper abuses dpms off to disable unused functions. Hence
  we also need to implement a default encoder disable function to do
  just that with the new encoder->disable callback.
- Note that we drop the cpt modeset verification in the commit
  callback, too. The right place to do this would be in the crtc's
  enable function, _after_ all the encoders are set up. But because
  not all encoders are converted yet, we can't do that. Hence disable
  this check temporarily as a minor concession to bisectability.

v2: Squash the dpms mode to only the supported values -
connector->dpms is for internal tracking only, we can hence avoid
needless state-changes a bit whithout causing harm.

v3: Apply bikeshed to disable|enable_ddi, suggested by Paulo Zanoni.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just prep work, not yet put to some use.

Note that because we're still using the crtc helper to switch modes
(and their complicated way to do partial modesets), we need to call
the encoder's disable function unconditionally.

But once this is cleaned up we shouldn't call the encoder's disable
function unconditionally any more, because then we know that we'll
only call it if the encoder is actually enabled. Also note that we
then need to be careful about which crtc we're filtering the encoder
list on: We want to filter on the crtc of the _current_ mode, not the
one we're about to set up.

For the enabling side we need to do the same trick. And again, we
should be able to simplify this quite a bit when things have settled
into place.

Also note that this simply does not take cloning into account, so dpms
needs to be handled specially for the few outputs where we even bother
with it.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just impendance matching with the the crtc helper stuff.

... and somehow the design of this all ended up in this commit here,
too ;-)

The big plan is that this new set of crtc display_funcs take full
responsibility of modeset operations for the entire display output
pipeline (by calling down into object-specific callbacks and
functions). The platform-specific callbacks simply know best what the
proper order is.

This has the drawback that we can't do minimal change-overs any more
if a modeset just disables one encoder in a cloned configuration
(because we will only expose a disable/enable action that takes
down/sets up the entire crtc including all encoders). Imo that's the
only sane way to do it though:
- The use-case for this is pretty minimal, even when presenting (at
  least sane people) should use a dual-screen output so that you can
  see your notes on your panel. Clone mode is imo BS.
- With all the clone mode constrains, shared resources, and special
  ordering requirements (which differ even on the same platform
  sometimes for different outputs) there's no way we'd get this right
  for all cases. Especially since this is a under-used feature.
- And to top it off: On haswell even dp link re-training requires us
  to take down the entire display pipe - otherwise the chip dies.

So the only sane way is to do a full modeset on every crtc where the
output config changes in any way.

To support global modeset (i.e. set the configuration for all crtcs at
once) we'd then add one more function to allocate global and shared
objects in the best ways (e.g. fdi links, pch plls, ...). The crtc
functions would then simply use the pre-allocated stuff (and shouldn't
be able to fail, ever). We could even do all the object pinning in
there (and maybe try to defragment the global gtt if we fail)!
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because that's what we're essentially calling. This is the first step
in untangling the crtc_helper induced dpms handling mess we have - at
the crtc level we only have 2 states and the magic is just in
selecting which one (and atm there isn't even much magic, but on
recent platforms where not even the crt output has more than 2 states
we could do better).
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Added new haswell_write_eld() to initialize Haswell HDMI audio registers
to generate an unsolicited response to the audio controller driver to
indicate that the controller sequence should start.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NWang Xingchao <xingchao.wang@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In order for udl vmap to work properly, we need to push the object
into the CPU domain before we start copying the data to the USB device.

This along with the udl change avoids userspace explicit mapping to
be used.

v2: add a flag for userspace to query to know if Intel kernel driver can
deal with the vmap flushing properly. In theory udl would need a flag also,
but I intend to push the patches very close to each other and other drivers
should do the right thing from the start.

I've added a test to my intel-gpu-tools prime branch, however testing
this is a bit messy since the only way to get udl to vmap is to rendering
something. I've tested this with real code as well to make sure it works.
Signed-off-by: NDave Airlie <airlied@redhat.com>
[danvet: resolved conflict, which required reallocating the PARAM
number to 21.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is left over from the old PLL sharing code and isn't useful now
that PLLs are shared when possible.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

New-ish devices have 3 pipes, so let's not just hardcode 2 but use the
for_each_pipe() macro and make struct intel_display_error_state is big
enough.

V2: Also add the number of pipes emitted (Chris Wilson)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use _PIPE macro to get correct register definition for IBX/CPT, discard
old variable "i" way.
Signed-off-by: NWang Xingchao <xingchao.wang@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
[danvet: Added the DIP_PORT_SEL #define from a preceeding patch in the
series that needs more work.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

HDMI audio related registers will be configured in write_eld callback.
Signed-off-by: NWang Xingchao <xingchao.wang@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Add hsw audio registers definition
Signed-off-by: NWang Xingchao <xingchao.wang@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Simply to make the ilk+ crtc disable path clearer and more symmetric
with the enable function.

Also switch to intel_crtc for the enable function.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

... and move a few others only used by i915_dma.c into the dri1
dungeon.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since it's redundant - we can get the attached encoder in the
functions themselves.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

A few things need adjustement:
- Change the dpms state by calling the dpms connector function and
  not some crtc helper internal callbacks. Otherwise this will break
  once we switch to our own dpms handling.
- Instead of tracking and restoring intel_crtc->dpms_mode use the
  connector's dpms variable - the former relies on the dpms compuation
  rules used by the crtc helper. And it would break when the encoder
  is cloned and the other output has a different dpms state. But luckily
  no one is crazy enough for that.
- Properly clear the connector -> encoder -> crtc linking, even when
  failing (note that the crtc helper removes the encoder -> crtc link
  in disabled_unused_functions for us).
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that all affected i830M systems have the pipe A quirk set,
we don't need to do any special dances in the overlay code any
longer. And reading through the code I'm rather dubios that it
actually does what it claims to do ...

As a nice benefit this rips out a users of the crtc helper dpms
callback.

v2: As suggested by Chris Wilson, replace the code by an appropriate
WARN to ensure that the pipe A is indeed running.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With the pipe A quirk properly fixed up for i830M, this shouldn't be
required any longer.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For some odd reason we've missed i830 and a i855 variant. Also
kill the two now redundant i830 entries.

v2: Don't add the missing 855 id to the pipe A quirk list, we seem to
lack justification for it.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Wrong order of parameters passed-in when calling hdmi/adpa
/lvds_pipe_enabled(), 2nd and 3rd parameters are reversed.

This bug was indroduced by

commit 1519b995
Author: Keith Packard <keithp@keithp.com>
Date:   Sat Aug 6 10:35:34 2011 -0700

    drm/i915: Fix PCH port pipe select in CPT disable paths

The reachable tag for this commit is v3.1-rc1-3-g1519b995Signed-off-by: NAnhua Xu <anhua.xu@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When invalidating the TLBs it is documentated as requiring a post-sync
write. Failure to do so seems to result in a GPU hang.

Exposure to this hang on IVB seems to be a result of removing the extra
stalls required for SNB pipecontrol workarounds:

commit 6c6cf5aa
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Jul 20 18:02:28 2012 +0100

    drm/i915: Only apply the SNB pipe control w/a to gen6

Note: Manually switch the pipe_control cmd to 4 dwords to avoid a
(silent) functional conflict with -next. This way will get a loud (but
conflict with next (since the scratch_addr has been deleted there).

Reported-and-tested-by: yex.tian@intel.com
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=53322Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: added note about merge conflict with -next.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

eDP is tons of fun. It turns out that at least the new MacBook Air 5,1
model absolutely doesn't like the new force vdd dance we've introduced
in

commit 6cb49835
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sun May 20 17:14:50 2012 +0200

    drm/i915: enable vdd when switching off the eDP panel

But that patch also tried to fix some neat edp sequence issue with the
force_vdd timings. Closer inspection reveals that we've raised
force_vdd only to do the aux channel communication dp_sink_dpms. If we
move the edp_panel_off below that, we don't need any force_vdd for the
disable sequence, which makes the Air happy.

Unfortunately the reporter of the original bug that the above commit
fixed is travelling, so we can't test whether this regresses things.
But my theory is that since we don't check for any power-off ->
force_vdd-on delays in edp_panel_vdd_on, this was the actual
root-cause of this failure. With that force_vdd dance completely
eliminated, I'm hopeful the original bug stays fixed, too.

For reference the old bug, which hopefully doesn't get broken by this:

https://bugzilla.kernel.org/show_bug.cgi?id=43163

In any case, regression fixers win over plain bugfixes, so this needs
to go in asap.

v2: The crucial pieces seems to be to clear the force_vdd flag
uncoditionally, too, in edp_panel_off. Looks like this is left behind
by the firmware somehow.

v3: The Apple firmware seems to switch off the panel on it's own, hence
we still need to keep force_vdd on, but properly clear it when switching
the panel off.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45671Tested-by: NRoberto Romer <sildurin@gmail.com>
Tested-by: NDaniel Wagner <wagi@monom.org>
Tested-by: NKeith Packard <keithp@keithp.com>
Cc: stable@vger.kernel.org
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

i2c_add_adapter() may do i2c transfers on the bus to detect supported
devices. Therefore the adapter needs to be all set before adding it. This
was not the case for the bit-banging fallback, resulting in an oops if the
device detection GMBUS transfers timed out. Fix the issue by calling
i2c_add_adapter() only after intel_gpio_setup().

LKML-Reference: <5021F00B.7000503@ionic.de>
Tested-by: NMihai Moldovan <ionic@ionic.de>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since forcewake is now protected by a spinlock, we don't need to grab
dev->struct_mutex any more. This way we can also get rid of a stale
comment, noticed by Ben Widawsky while reviewing some locking changes.

v2: Kill the unused variable ret, noticed by Fengguang Wu.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This has originally been introduced to not oversubscribe the dp links
in

commit 885a5fb5
Author: Zhenyu Wang <zhenyuw@linux.intel.com>
Date:   Tue Jan 12 05:38:31 2010 +0800

    drm/i915: fix pixel color depth setting on eDP

Since then we've fixed up the dp link bandwidth calculation code and
should now automatically fall back to 6bpc dithering. So this is
unnecessary.

Furthermore it seems to break the new MacbookPro with retina display,
hence let's just rip this out.
Reported-by: NBenoit Gschwind <gschwind@gnu-log.net>
Cc: Benoit Gschwind <gschwind@gnu-log.net>
Cc: Francois Rigaut <frigaut@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Tested-by: NBenoit Gschwind <gschwind@gnu-log.net>
Tested-by: Bernhard Froemel <froemel at vmars tuwien.ac.at>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

--

Testing feedback highgly welcome, and thanks for Benoit for finding
out that the bpc computations are busted.
-Daniel

When you reopen the lid on a laptop with PCH, the panel suddenly goes
blank sometimes.  It seems because BLC_PWM_CPU_CTL register is cleared
to zero when BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1 registers are
enabled.

This patch fixes the problem by moving the call of the function setting
BLC_PWM_CPU_CTL after enabling other two registers.
Reported-and-tested-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we don't find the exact refresh rate, go with the next one. This
makes some modes work for me. They won't have the best settings, but
will at least have something. Just returning from this function when
we don't find the perfect settings does not help us at all.

Version 2:
  - Remove duplicate lines on the clock table.
  - Add back debug message with refresh, p, n2 and r2.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

  - intel_encoder->type is INTEL_OUTPUT_SOMETHING
  - drm_encoder->encoder_type is DRM_MODE_ENCODER_SOMETHING

Here we're using intel_encoder, so compare the oranges against
oranges. While at it, rename the variable to "intel_encoder" so we
keep our naming standards used everywhere.

Luckily this was not a bug because both DRM_MODE_ENCODER_DAC and
INTEL_OUTPUT_ANALOG are defined as 1. This is the only case where the
drm definition matches the intel definition.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Avoid the forcewake overhead when simply retiring requests, as often the
last seen seqno is good enough to satisfy the retirment process and will
be promptly re-run in any case. Only ensure that we force the coherent
seqno read when we are explicitly waiting upon a completion event to be
sure that none go missing, and also for when we are reporting seqno
values in case of error or debugging.

This greatly reduces the load for userspace using the busy-ioctl to
track active buffers, for instance halving the CPU used by X in pushing
the pixels from a software render (flash). The effect will be even more
magnified with userptr and so providing a zero-copy upload path in that
instance, or in similar instances where X is simply compositing DRI
buffers.

v2: Reverse the polarity of the tachyon stream. Daniel suggested that
'force' was too generic for the parameter name and that 'lazy_coherency'
better encapsulated the semantics of it being an optimization and its
purpose. Also notice that gen6_get_seqno() is only used by gen6/7
chipsets and so the test for IS_GEN6 || IS_GEN7 is redundant in that
function.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I have the faint hope that the total absence of any locking for the
rps code wasn't too good an idea and could very well have caused some
rc6 related regressions.

Unfortunately we've never managed to reproduce these issues on any of
our own machines, so the only way to go about this is to enable it and
see what happens.

While at it, kill some stale comments and improve the logging.
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We change the drps/ips sw/hw state from different callers: Our own irq
handler, the external intel-ips module and from process context. Most
of these callers don't take any lock at all.

Protect everything by making the mchdev_lock irqsave and grabbing it in
all relevant callsites. Note that we have to convert a few sleeps in the
drps enable/disable code to delays, but alas, I'm not volunteering to
restructure the code around a few work items.

For paranoia add a spin_locked assert to ironlake_set_drps, too.

v2: Move one access inside the lock protection. Caught by the
dev_priv->ips mass-rename ...

v3: Resolve rebase conflict.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Like all the other drps/ips stuff. Hence add the corresponding check,
give the function a preciser prefix and move the single reg clearing into
the rps handling function, too.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's only ever a pointer to the global mchdev_lock, and we don't use
it at all.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>