This statenment became false here:

commit 4fc688ce
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Fri Nov 2 11:14:01 2012 -0700

    drm/i915: protect RPS/RC6 related accesses (including PCU) with a new mutex
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's unused, and nowadays specifying unknown parameters no longer
prevents modules from being loaded.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Not sure anyone cares about this information. I suppose most people
would just look at /proc/interrupts instead.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The eDP spec defines some points where after you do action A, you have
to wait some time before action B. The thing is that in our driver
action B does not happen exactly after action A, but we still use
msleep() calls directly. What this patch does is that we record the
timestamp of when action A happened, then, just before action B, we
look at how much time has passed and only sleep the remaining amount
needed.

With this change, I am able to save about 5-20ms (out of the total
200ms) of the backlight_off delay and completely skip the 1ms
backlight_on delay. The 600ms vdd_off delay doesn't happen during
normal usage anymore due to a previous patch.

v2: - Rename ironlake_wait_jiffies_delay to intel_wait_until_after and
      move it to intel_display.c
    - Fix the msleep call: diff is in jiffies
v3: - Use "tmp_jiffies" so we don't need to worry about the value of
      "jiffies" advancing while we're doing the math.
v4: - Rename function again.
    - Move function to i915_drv.h.
    - Store last_power_cycle at edp_panel_off too.
    - Use msecs_to_jiffies_timeout, then replace the msleep with an
      open-coded version that avoids the extra +1 jiffy.
    - Try to add units to every variable name so we don't confuse
      jiffies with milliseconds.
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>

My OCD just couldn't let this slide. Spotted while reviewing Ville's
patch to only flip planes when we have FBC.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We use this hook starting from ILK onwards, so change the prefix
accordingly. Also rename functions/struct names used from
haswell_update_wm that are relevant to ILK already.

No functional change.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We now have a very clear method of disabling LP1+ wartermarks,
and we can actually detect if we actually did disable them, or
if they were already disabled. Use that to clean up the
WaCxSRDisabledForSpriteScaling:ivb handling.

I was hoping to apply the workaround in a way that wouldn't
require a blocking wait, but sadly IVB really does appear to
require LP1+ watermarks to be off for an entire frame before
enabling sprite scaling. Simply disabling LP1+ watermarks
during the previous frame is not enough, no matter how early
in the frame we do it :(
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't actually do anything with the information yet, but parse and
log what's in the VBT.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that all the infrastructure is in place and all the tests from
pm_pc8 pass, we can finally enable the feature.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So we'll get a fault when someone tries to access the mmap, then we'll
wake up from D3.

v2: - Rebase
v3: - Use gtt active/inactive

Testcase: igt/pm_pc8/gem-mmap-gtt
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Add comment + WARN as discussed with Paulo on irc.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Don't touch DPFC_RECOMP_CTL on FBC2, use RMW to update
the FBC_CONTROL on FBC1 to make it easier for people to
experiment with different numbers. Also fix the interval
mask for FBC1.

v2: Rebased
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Rebased on latest code
Signed-off-by: NShobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: NYogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Reviewed-by: Jani Nikula<jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Every ring seems to have a BB_ADDR registers, so include them all in the
error state.

v2: Also include the _UDW on BDW
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This patch adds the initial infrastructure to allow a Runtime PM
implementation that sets the device to its D3 state. The patch just
adds the necessary callbacks and the initial infrastructure.

We still don't have any platform that actually uses this
infrastructure, we still don't call get/put in all the places we need
to, and we don't have any function to save/restore the state of the
registers. This is not a problem since no platform uses the code added
by this patch. We have a few people simultaneously working on runtime
PM, so this initial code could help everybody make their plans.

V2: - Move some functions to intel_pm.c
    - Remove useless pm_runtime_allow() call at init
    - Remove useless pm_runtime_mark_last_busy() call at get
    - Use pm_runtime_get_sync() instead of 2 calls
    - Add a WARN to check if we're really awake

V3: - Rebase.

V4: - Don't need to call pci_{save,restore}_state and
      pci_set_power_sate, since they're already called by the PCI
      layer
    - Remove wrong pm_runtime_enable() call at init_runtime_pm
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Shovel a bit more of the the code into the setup function, and call
it earlier. Otherwise lockdep is unhappy since we cancel the delayed
resume work before it's initialized.

While at it also shovel the pc8 setup code into the same functions.
I wanted to also ditch the header declaration of the hws pc8 functions,
but for unfathomable reasons that stuff is in intel_display.c instead
of intel_pm.c.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71980Tested-by: NGuo Jinxian <jinxianx.guo@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Atm we call intel_display_power_enabled() from
i915_capture_error_state() in IRQ context and then take a mutex. To fix
this add a new intel_display_power_enabled_sw() which returns the domain
state based on software tracking as opposed to reading the actual HW
state.

Since we use domain_use_count for this without locking on the reader
side make sure we increase the counter only after enabling all required
power wells and decrease it before disabling any of these power wells.

Regression introduced in
commit 1b02383464b4a915627ef3b8fd0ad7f07168c54c
Author: Imre Deak <imre.deak@intel.com>
Date:   Tue Sep 24 16:17:09 2013 +0300

    drm/i915: support for multiple power wells

Note that atm we depend on the value returned by
intel_display_power_enabled_sw() in i915_capture_error_state() to avoid
unclaimed register access reports. This was never guaranteed though,
since another thread can disable the power concurrently. If this is a
problem we need another explicit way to disable the reporting during
error captures.

v2:
- remove barriers as the caller can't depend on the value
  returned from i915_capture_error_state_sw() anyway (Ville)
- dump the state of pipe/transcoder power domain state (Daniel)
Reported-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Split vlv force wake routines to help individually control Media/Render
well based on the register access.

We've seen power savings in the lower sub-1W range on workloads that
only need on of the power wells, e.g. glbenchmark, media playback

Note: The same split isn't there for the forcewake queue, only the
forcwake domains are split.
Signed-off-by: NDeepak S <deepak.s@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Rebase on top of the removed forcewake hack in the ring irq
get/put code and add a note to add Deepak's answer to Chris question.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Added power well arguments to all the force wake routines
to help us individually control power well based on the
scenario.
Signed-off-by: NDeepak S <deepak.s@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Resolve conflict with the removed forcewake hack and drop one
spurious hunk Jesse noticed.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Add a debugfs entry showing the use-count for all power domains of each
power well.

v3: address comments from Paulo:
- simplify power_domain_str() by using a switch table
- move power_well::domain_count to power_domains
- WARN_ON decrementing a 0 refcount
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So far we distinguished platforms without a dynamic power well with
the HAS_POWER_WELL macro and for such platforms we didn't call any power
domain functions. Instead of doing this check we can add an always-on
power well for these platforms and call the power domain functions
unconditionally. For always-on power wells we only increase/decrease
their refcounts, otherwise they are nop.

This makes high level driver code more readable and as a bonus provides
some idea of the current power domains state for all platforms (once
the relevant debugfs entry is added).

v3: rename intel_power_wells to i9xx_always_on_power_well (Paulo)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Instead of using a separate function to check whether a power domain is
is always on, add an always-on power well covering all these power
domains and do the usual get/put on these unconditionally. Since we
don't assign a .set handler for these the get/put won't have any effect
besides the adjusted refcount.

This makes the code more readable and provides debug info also on the
use of always-on power wells (once the relevant debugfs entry is added.)

v3: make is_always_on to be bool instead of a bit field (Paulo)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

HW generations so far had only one always-on power well and optionally
one dynamic power well. Upcoming HW gens may have multiple dynamic power
wells, so add some infrastructure to support them.

The idea is to keep the existing power domain API used by the rest of
the driver and create a mapping between these power domains and the
underlying power wells. This mapping can differ from one HW to another
but high level driver code doesn't need to know about this. Through the
existing get/put API it would just ask for a given power domain and the
power domain framework would make sure the relevant power wells get
enabled in the right order.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This way the code is simpler and can also be used for other platforms
where the audio power domain->power well mapping is different.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If the hardware does not support package C8, then do not even schedule
work to enable it. Thereby we can eliminate a bunch of dangerous work.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This was forgotten in

commit 9d1cb914
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Fri Nov 1 13:32:08 2013 -0200

    drm/i915: avoid unclaimed registers when capturing the error state

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The backlight enable code now has the smarts to do the right thing. Only
do backlight register save/restore in UMS.

Some VLV specific code gets dropped as UMS is not supported on VLV.

v2: Move save/restore to UMS instead of removing completely (Daniel).
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No longer needed. We now have fully cached max backlight values.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The quirk was added as what I'd say was a stopgap measure in

commit e85843be
Author: Kamal Mostafa <kamal@canonical.com>
Date:   Fri Jul 19 15:02:01 2013 -0700

    drm/i915: quirk no PCH_PWM_ENABLE for Dell XPS13 backlight

without really digging into what was going on.

Also, as mentioned in the related bug [1], having the quirk regressed
some of the machines it was supposed to fix to begin with, and there
were patches posted to disable the quirk on such machines [2]!

The fact is, we do need the BLM_PCH_PWM_ENABLE bit set to have
backlight. With the quirk, we've relied on BIOS to have set it, and our
save/restore code to retain it. With the full backlight setup at enable,
we have no place for things that rely on previous state.

With the per platform hooks, we've also made a change in the PCH
platform enable order: setting the backlight duty cycle between CPU and
PCH PWM enable. Some experimenting and

commit 770c1231
Author: Takashi Iwai <tiwai@suse.de>
Date:   Sat Aug 11 08:56:42 2012 +0200

    drm/i915: Fix blank panel at reopening lid

indicate that we can't set the backlight before enabling CPU PWM; the
value just won't stick. But AFAICT we should do it before enabling the
PCH PWM.

Finally, any fallout we should fix properly, preferrably without quirks,
and absolutely without quirks that rely on existing state. With the per
platform hooks have much more flexibility to adjust the sequence as
required by platforms.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=47941
[2] http://lkml.kernel.org/r/1378229848-29113-1-git-send-email-kamal@canonical.comSigned-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For what we care about ULT and ULX are interchangeable. We know of 3
types of pciids for these cases. I am not sure if at some point we will
need to distinguish ULT and ULX.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The backlight code has grown rather hairy, not least because the
hardware registers and bits have repeatedly been shuffled around. And
this isn't expected to get any easier with new hardware. Make things
easier for our (read: my) poor brains, and split the code up into chip
specific functions.

There should be no functional changes.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move from dev_priv to connector->panel. We still don't allow multiple
sysfs interfaces, though.

There should be no functional changes, except for a slight reordering of
connector backlight and sysfs destroy calls. (This change happens now
that the backlight device is actually per-connector, even though the
destroy calls became per-connector earlier.)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This ioctl returns reset stats for specified context.

The struct returned contains context loss counters.

reset_count:    all resets across all contexts
batch_active:   active batches lost on resets
batch_pending:  pending batches lost on resets

v2: get rid of state tracking completely and deliver only counts. Idea
    from Chris Wilson.

v3: fix commit message

v4: default context handled inside i915_gem_context_get_hang_stats

v5: reset_count only for priviledged process

v6: ctx=0 needs CAP_SYS_ADMIN for batch_* counters (Chris Wilson)

v7: context hang stats never returns NULL

v8: rebased on top of reworked context hang stats
    DRM_RENDER_ALLOW for ioctl

v9: use DEFAULT_CONTEXT_ID. Improve comments for ioctl struct members
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Cc: Ian Romanick <idr@freedesktop.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NIan Romanick <ian.d.romanick@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

reset_counter will be incremented twice per successful
reset. Odd values mean reset is in progress and even values
mean that reset has completed.

Reset status ioctl introduced in following commit
needs to deliver global reset count to userspace so
use reset_counter to derive the actual reset count
for the gpu

Note that reset in progress is enough to increment
the counter.

v2: wedged equals reset in progress (Daniel Vetter)

v3: Fixed stale comments (Damien Lespiau)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

vlv_dpio_read/write should be describe more in PHY centric instead of
display controller centric.
Create a enum dpio_channel for channel index and enum dpio_phy for PHY
index.  This should better to gather for upcoming platform.

v2: Rebase the code based on
drm/i915/vlv: Fix typo in the DPIO register define.

v3: Rename vlv_phy to dpio_phy_iosf_port and define additional macro
DPIO_PHY, and remove unrelated change. (Ville)
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NChon Ming Lee <chon.ming.lee@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Broadwell PSR support is a superset of Haswell. With this simple
register base calculation, everything that worked on HSW for eDP PSR
should work on BDW.

Note that Broadwell provides additional PSR support. This is not
addressed at this time.

v2: Make the HAS_PSR include BDW

v3: Use the correct offset (I had incorrectly used one from my faulty
brain) (Art!)

v4: It helps if you git add

v5: Be explicit about not setting min link entry time for BDW. This
should be no functional change over v4 (Jani)
Reviewed-by: NArt Runyan <arthur.j.runyan@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Squash in fixup from Ben to synchronize the GT mailbox commands.

CC: Art Runyan <arthur.j.runyan@intel.com>
Reviewed-by: NArt Runyan <arthur.j.runyan@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just like Haswell, but with the small twist that the panel fitter for pipe A is
now also in the always-on power well.

v2: Use the new HAS_POWER_WELL macro.

v3: Rebase on top of intel_using_power_well patches.

v4: This time actually update the PFIT check correctly so that the
pipe A pfit is in the always-on domain.

v5: Rebase on top of the VGA power domain addition.

v6: Rebase on top of the new power domain infrastructure. Also pimp the commit
message a bit while at it.

v7: Use IS_BROADWELL instead of IS_GEN8 (Ville).

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> (v1)
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For now it's just equivalent to IS_GEN8, but in the future we might
want to change that (e.g., on Gen 7 we have IS_VALLEYVIEW,
IS_IVYBRIDGE and IS_HASWELL).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Aside from the potential size increase of the PPGTT, the primary
difference from previous hardware is the Page Directories are no longer
carved out of the Global GTT.

Note that the PDE allocation is done as a 8MB contiguous allocation,
this needs to be eventually fixed (since driver reloading will be a
pain otherwise). Also, this will be a no-go for real PPGTT support.

v2: Move vtable initialization

v3: Resolve conflicts due to patch series reordering.

v4: Rebase on top of the address space refactoring of the PPGTT
support. Drop Imre's r-b tag for v2, too outdated by now.

v5: Free the correct amount of memory, "get_order takes size not a page
count." (Imre)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The interrupt handling implementation remains the same as previous
generations with the 4 types of registers, status, identity, mask, and
enable. However the layout of where the bits go have changed entirely.
To address these changes, all of the interrupt vfuncs needed special
gen8 code.

The way it works is there is a top level status register now which
informs the interrupt service routine which unit caused the interrupt,
and therefore which interrupt registers to read to process the
interrupt. For display the division is quite logical, a set of interrupt
registers for each pipe, and in addition to those, a set each for "misc"
and port.

For GT the things get a bit hairy, as seen by the code. Each of the GT
units has it's own bits defined. They all look *very similar* and
resides in 16 bits of a GT register. As an example, RCS and BCS share
register 0. To compact the code a bit, at a slight expense to
complexity, this is exactly how the code works as well. 2 structures are
added to the ring buffer so that our ring buffer interrupt handling code
knows which ring shares the interrupt registers, and a shift value (ie.
the top or bottom 16 bits of the register).

The above allows us to kept the interrupt register caching scheme, the
per interrupt enables, and the code to mask and unmask interrupts
relatively clean (again at the cost of some more complexity).

Most of the GT units mentioned above are command streamers, and so the
symmetry should work quite well for even the yet to be implemented rings
which Broadwell adds.

v2: Fixes up a couple of bugs, and is more verbose about errors in the
Broadwell interrupt handler.

v3: fix DE_MISC IER offset

v4: Simplify interrupts:
I totally misread the docs the first time I implemented interrupts, and
so this should greatly simplify the mess. Unlike GEN6, we never touch
the regular mask registers in irq_get/put.

v5: Rebased on to of recent pch hotplug setup changes.

v6: Fixup on top of moving num_pipes to intel_info.

v7: Rebased on top of Egbert Eich's hpd irq handling rework. Also
wired up ibx_hpd_irq_setup for gen8.

v8: Rebase on top of Jani's asle handling rework.

v9: Rebase on top of Ben's VECS enabling for Haswell, where he
unfortunately went OCD on the gt irq #defines. Not that they're still
not yet fully consistent:
- Used the GT_RENDER_ #defines + bdw shifts.
- Dropped the shift from the L3_PARITY stuff, seemed clearer.
- s/irq_refcount/irq_refcount.gt/

v10: Squash in VECS enabling patches and the gen8_gt_irq_handler
refactoring from Zhao Yakui <yakui.zhao@intel.com>

v11: Rebase on top of the interrupt cleanups in upstream.

v12: Rebase on top of Ben's DPF changes in upstream.

v13: Drop bdw from the HAS_L3_DPF feature flag for now, it's unclear what
exactly needs to be done. Requested by Ben.

v14: Fix the patch.
- Drop the mask of reserved bits and assorted logic, it doesn't match
  the spec.
- Do the posting read inconditionally instead of commenting it out.
- Add a GEN8_MASTER_IRQ_CONTROL definition and use it.
- Fix up the GEN8_PIPE interrupt defines and give the GEN8_ prefixes -
  we actually will need to use them.
- Enclose macros in do {} while (0) (checkpatch).
- Clear DE_MISC interrupt bits only after having processed them.
- Fix whitespace fail (checkpatch).
- Fix overtly long lines where appropriate (checkpatch).
- Don't use typedef'ed private_t (maintainer-scripts).
- Align the function parameter list correctly.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net> (v4)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

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