Two code changes:
- Extract i915_gem_shrinker_init.
- Inline i915_gem_object_is_purgeable since we open-code it everywhere
  else too.

This already has the benefit of pulling all the shrinker code
together, next patch adds a bit of kerneldoc.
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use both up/down manual ei calcuations for symmetry and greater
flexibility for reclocking, instead of faking the down interrupt based
on a fixed integer number of up interrupts.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we idle, we set the GPU frequency to the hardware minimum (not user
minimum). We introduce a new variable to distinguish between the
different roles, and to allow easy tuning of the idle frequency without
impacting over aspects of RPS. Setting the minimum frequency should be a
safety blanket as the pcu on the GPU should be power gating itself
anyway. However, in order for us to do set the absolute minimum
frequency, we need to relax a few of our assertions that we do not
exceed the user limits.

v2: Add idle_freq
v3: Init idle_freq for vlv and add a bunch of WARNs
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

GGTT views are only applicable when dealing with GGTT. Change the code to
reject ggtt_view where it should not be used and require it when it should
be.

v2:
- Dropped _ppgtt_ infixes, allow both types to be passed
- Disregard other but normal views when no view is specified
- More checks that valid parameters are passed
- More readable error checking

v3:
- Prefer WARN_ONCE over BUG_ON when there is code path for failure
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
[danvet: Drop unecessary forward decl from earlier patch iterations.]
[danvet: Remove unused variable spotted by Tvrtko.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Same as

commit c883ef1b
Author: Mika Kuoppala <miku@iki.fi>
Date:   Tue Oct 28 17:32:30 2014 +0200

    drm/i915: Redefine WARN_ON to include the condition

but for WARN_ON_ONCE. Since the kernel WARN_ON_ONCE actually picks up
*our* version of WARN_ON, we end up with messages like

[  838.285319] WARN_ON(!__warned)

which are not that helpful.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For SKL, register definition for RPNSWREQ (A008), RPSTAT1(A01C)
have changed slightly. Also on SKL, frequency is specified in
units of 16.66 MHZ, compared to 50 MHZ for most of the earlier
platforms and the time values are expressed in units of 1.33 us,
compared to 1.28 us for earlier platforms.
Added new macros for the aforementioned changes.

v2: Renamed the GT_FREQ_FROM_PERIOD macro to GT_INTERVAL_FROM_US (Damien)

v3: Removed the implicit use of dev_priv in GT_INTERVAL_FROM_US macro (Chris)
Signed-off-by: NAkash Goel <akash.goel@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Assuming the PND deadline mechanism works reasonably we should do
memory requests as early as possible so that PND has schedule the
requests more intelligently. Currently we're still calculating
the watermarks as if VLV/CHV are identical to g4x, which isn't
the case.

The current code also seems to calculate insufficient watermarks
and hence we're seeing some underruns, especially on high resolution
displays.

To fix it just rip out the current code and replace is with something
that tries to utilize PND as efficiently as possible.

We now calculate the WM watermark to trigger when the FIFO still has
256us worth of data. 256us is the maximum deadline value supoorted by
PND, so issuing memory requests earlier would mean we probably couldn't
utilize the full FIFO as PND would attempt to return the data at
least in at least 256us. We also clamp the watermark to at least 8
cachelines as that's the magic watermark that enabling trickle feed
would also impose. I'm assuming it matches some burst size.

In theory we could just enable trickle feed and ignore the WM values,
except trickle feed doesn't work with max fifo mode anyway, so we'd
still need to calculate the SR watermarks. It seems cleaner to just
disable trickle feed and calculate all watermarks the same way. Also
trickle feed wouldn't account for the 256us max deadline value, thoguh
that may be a moot point in non-max fifo mode sicne the FIFOs are fairly
small.

On VLV max fifo mode can be used with either primary or sprite planes.
So the code now also checks all the planes (apart from the cursor)
when calculating the SR plane watermark.

We don't have to worry about the WM1 watermarks since we're using the
PND deadline scheme which means the hardware ignores WM1 values.

v2: Use plane->state->fb instead of plane->fb
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Introduce struct vlv_wm_values to house VLV watermark/drain latency
values. We start by using it when computing the drain latency values.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we have a single unclaimed register, we will have lots. A WARN for
each one makes the machine unusable and does not aid debugging. Convert
the i915.mmio_debug option to a counter for how many WARNs to fire
before shutting up. Even when i915.mmio_debug was disabled it would
continue to shout an *ERROR* for every interrupt, without any
information at all for debugging.

The massive verbiage was added in
commit 5978118c
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Wed Jul 16 17:49:29 2014 -0300

    drm/i915: reorganize the unclaimed register detection code

v2: Automatically enable invalid mmio reporting for the *next* invalid
access if mmio_debug is disabled by default. This should give us clearer
debug information without polluting the logs too much.
v3: Compile fixes, rebase.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Update modparam text per the thread.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Apparently, this has never worked reliably and is currently disabled. Also, the
gains are not particularly impressive. Thus rather than try to keep unused code
from decaying and having to update it for other driver changes, it was decided
to simply remove it.

For: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Kill the blt/render tracking we currently have and use the frontbuffer
tracking infrastructure.

Don't enable things by default yet.

v2: (Rodrigo) Fix small conflict on rebase and typo at subject.
v3: (Paulo) Rebase on RENDER_CS change.
v4: (Paulo) Rebase.
v5: (Paulo) Simplify: flushes don't have origin (Daniel).
            Also rebase due to patch order changes.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have similar macros for crtcs and encoders, and the pattern happens
often enough to justify the macro.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We want to port FBC to the frontbuffer tracking infrastructure, but
for that we need to know what caused the object invalidation so
we can react accordingly: CPU mmaps need manual, GTT mmaps and
flips don't need handling and ring rendering needs nukes.

v2: - s/ORIGIN_RENDER/ORIGIN_CS/ (Daniel, Rodrigo)
    - Fix copy/pasted wrong documentation
    - Rebase
v3: - Rebase
v4: - Don't pass the operation to flushes (Daniel).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Implicit usage of local variables in macros isn't exactly the greatest
thing in the world, especially when that variable is the drm device and
we want to move towards a broader use of the i915 device structure.

Let's make for_each_sprite() take dev_priv as its first argument then.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Chris Wilson <chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Implicit usage of local variables in macros isn't exactly the greatest
thing in the world, especially when that variable is the drm device and
we want to move towards a broader use of the i915 device structure.

Let's make for_each_plane() take dev_priv as its first argument then.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Chris Wilson <chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Lots of lines to remove!
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
[danvet: Fixup makefile.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In execlist mode, the ringbuf is a function of the ring and context whereas in
legacy mode, it is derived from the ring alone. Thus the calculation required to
determine the ringbuf pointer from the ring (and context) also needs to test
execlist mode or not. This is messy.

Further, the request structure holds a pointer to both the ring and the context
for which it was created. Thus, given a request, it is possible to derive the
ringbuf in either legacy or execlist mode. Hence it is necessary to pass just
the request in to all the low level functions rather than some combination of
request, ring, context and ringbuf. However, rather than recalculating it each
time, it is much simpler to just cache the ringbuf pointer in the request
structure itself.

Caching the pointer means the calculation is done once at request creation time
and all further code and simply read it directly from the request structure.

OTC-Jira: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
[danvet: Drop contentless comment in lrc alloc request entirely. And
spelling fix in the commit message.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Adding VBT version check for low_vswing field, and correcting parsing

v3: (Damien)
 - Restrain the scope of the 'vswing' variable
 - Use the more idiomatic "ev_priv->vbt.edp_low_vswing = vswing == 0;"
  instead of if (foo) var = true; else var = false;
 - Shorten edp_vswing_premph_setting to edp_vswing_premph to fit in 80 chars
 - Add the version from which the edp_vswing_premph field is valid in the
  struct definition

Reviewed-by: Satheeshakrishna M <satheeshakrishna.m@intel.com> (v2)
Signed-off-by: NSonika Jindal <sonika.jindal@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When converting from implicitly tracked execlist queue items to ref counted
requests, not all frees of requests were replaced with unrefs, and extraneous
refs/unrefs of contexts were added.
Correct the unbalanced refcount & replace the frees.
Remove a noisy warning when hitting the request creation path.

drm_i915_gem_request and intel_context are both kref reference counted
structures. Upon allocation, drm_i915_gem_request's ref count should be
bumped using kref_init. When a context is assigned to the request,
the context's reference count should be bumped using i915_gem_context_reference.
i915_gem_request_reference will reduce the context reference count when
the request is freed.

Problem introduced in
commit 6d3d8274
Author:     Nick Hoath <nicholas.hoath@intel.com>
AuthorDate: Thu Jan 15 13:10:39 2015 +0000

     drm/i915: Subsume intel_ctx_submit_request in to drm_i915_gem_request

v2: Added comments explaining how the ctx pointer and the request object should
be ref-counted. Removed noisy warning.

v3: Cleaned up the language used in the commit & the header
description (Thanks David Gordon)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88652Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NThomas Daniel <thomas.daniel@intel.com>
Reviewed-by: NDaniel Vetter <daniel@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

When one EU is disabled in a particular subslice, we can tune how the
work is spread between subslices to improve EU utilization.

v2: - Use a bitfield to record which subslice(s) has(have) 7 EUs. That
      will also make the machinery work if several sublices have 7 EUs.
      (Jeff Mcgee)
    - Only apply the different hashing algorithm if the slice is
      effectively unbalanced by checking there's a single subslice with
      7 EUs. (Jeff Mcgee)

v3: Fix typo in comment (Jeff Mcgee)

Issue: VIZ-3845
Cc: Jeff Mcgee <jeff.mcgee@intel.com>
Reviewed-by: NJeff Mcgee <jeff.mcgee@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Read fuse registers to determine the available slice total,
subslice total, subslice per slice, EU total, and EU per subslice
counts of the SKL device. The EU per subslice attribute is more
precisely defined as the maximum EU available on any one subslice,
since available EU counts may vary across subslices due to fusing.
Set flags indicating the SKL device's slice/subslice/EU (SSEU)
power gating capability. Make all values available via debugfs
entry 'i915_sseu_status'.

v2: Several small clean-ups suggested by Damien. Most notably,
    used smaller types for the new device info fields to reduce
    memory usage and improved the clarity/readability of the
    method used to extract attribute values from the fuse
    registers.
Signed-off-by: NJeff McGee <jeff.mcgee@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When reviewing patch that fixes VGA on BDW Halo Jani noticed that
we also had other ULT IDs that weren't listed there.

So this follow-up patch add these pci-ids as halo and fix comments
on i915_pciids.h

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We use the pid of the process which opened our device when
we track which was the culprit of the gpu hang. But as that
file descriptor might get inherited, we might blame the
wrong process when we record the error state.

Track process identifiers in requests to always find
the correct offender.

v2: Track only user processes (Chris)

Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
[danvet: drop NULL check before put_pid as suggested by Chris.]
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NNick Hoath <nicholas.hoath@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The last (only?) user of this was removed in:

  commit 2208d655
  Author: Daniel Vetter <daniel.vetter@ffwll.ch>
  Date:   Fri Nov 14 09:25:29 2014 +0100

    drm/i915: drop WaSetupGtModeTdRowDispatch:snb
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There have been quite a bit of development lately, leaving behing lonely
protypes. Time to bid them farewell.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Introduce a PV INFO structure, to facilitate the Intel GVT-g
technology, which is a GPU virtualization solution with mediated
pass-through. This page contains the shared information between
i915 driver and the host emulator. For now, this structure utilizes
an area of 4K bytes on HSW GPU's unused MMIO space. Future hardware
will have the reserved window architecturally defined, and layout
of the page will be added in future BSpec.

The i915 driver load routine detects if it is running in a VM by
reading the contents of this PV INFO page. Thereafter a flag,
vgpu.active is set, and intel_vgpu_active() is used by checking
this flag to conclude if GPU is virtualized with Intel GVT-g. By
now, intel_vgpu_active() will return true, only when the driver
is running as a guest in the Intel GVT-g enhanced environment on
HSW platform.

v2:
take Chris' comments:
        - call the i915_check_vgpu() in intel_uncore_init()
        - sanitize i915_check_vgpu() by adding BUILD_BUG_ON() and debug info
take Daniel's comments:
        - put the definition of PV INFO into a new header - i915_vgt_if.h
other changes:
        - access mmio regs by readq/readw in i915_check_vgpu()

v3:
take Daniel's comments:
        - move the i915/vgt interfaces into a new i915_vgpu.c
        - update makefile
        - add kerneldoc to functions which are non-static
        - add a DOC: section describing some of the high-level design
        - update drm docbook
other changes:
        - rename i915_vgt_if.h to i915_vgpu.h

v4:
take Tvrtko's comments:
        - fix a typo in commit message
        - add debug message when vgt version mismatches
        - rename low_gmadr/high_gmadr to mappable/non-mappable in PV INFO
          structure
Signed-off-by: NYu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: NJike Song <jike.song@intel.com>
Signed-off-by: NEddie Dong <eddie.dong@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To be used from the new addfb2 extension.

v2:
- Drop Intel-specific untiled modfier.
- Move to drm_fourcc.h.
- Document layouts a bit and denote them as platform-specific and not
  useable for cross-driver sharing.
- Add Y-tiling for completeness.
- Drop special docstring markers to avoid confusing kerneldoc.

v3: Give Y-tiling a unique idea, noticed by Tvrtko.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> (v1)
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since the mapping from CRTCs to planes is fixed, looking at the CRTC
is essentially the same as looking at the plane. Also, the next
patches wil start using the frontbuffer_bits macros, and they take the
pipe as the parameter instead of the plane, and this could differ on
gens 2 and 3.

Another nice thing is that we don't risk accidentally initializing
things to PLANE_A if we don't set the value before it is used for the
first time. But this shouldn't be a problem with the current code.

V2: Rebase.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> (v1)
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Add Skylake stepping Revision IDs definitions.

v1: Use existing revision id.
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Use magic __I915__ and bikeshed #defines as suggested by
Damien.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The check for previously reserved stolen space size for FBC in
i915_gem_stolen_setup_compression() did not take the compression
threshold into account. Fix this by storing and comparing to
uncompressed size instead.

The bug has been introduced in

commit 5e59f717
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date:   Mon Jun 30 10:41:24 2014 -0700

    drm/i915: Try harder to get FBC

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88975Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Replace the valleyview_set_rps() and gen6_set_rps() calls with
intel_set_rps() which itself does the IS_VALLEYVIEW() check. The
code becomes simpler since the callers don't have to do this check
themselves.

Most of the change was performe with the following semantic patch:
@@
expression E1, E2, E3;
@@
- if (IS_VALLEYVIEW(E1)) {
-  valleyview_set_rps(E2, E3);
- } else {
-  gen6_set_rps(E2, E3);
- }
+ intel_set_rps(E2, E3);

Adding intel_set_rps() and making valleyview_set_rps() and gen6_set_rps()
static was done manually. Also valleyview_set_rps() had to be moved a
bit avoid a forward declaration.

v2: Use a less greedy semantic patch

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now when we declare gpu errors only through our own dedicated
hangcheck workqueue there is no need to have a separate workqueue
for handling the resetting and waking up the clients as the deadlock
concerns are no more.

The only exception is i915_debugfs::i915_set_wedged, which triggers
error handling through process context. However as this is only used through
test harness it is responsibility for test harness not to introduce hangs
through both debug interface and through hangcheck mechanism at the same time.

Remove gpu_error.work and let the hangcheck work do the tasks it used to.

v2: Add a big warning sign into i915_debugfs::i915_set_wedged (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Mainly taking care of some register offsets, otherwise things are similar to
hsw. Also, programming ddi aux to use hardcoded values for psr data select.

v2: introduce  EDP_PSR_AUX_BASE macro (Chris)
v3: Moving to HW tracking for SKL+ platforms, so activating source psr during
psr_enabling and then avoiding psr entries and exits for each frontbuffer
updates.
v4: Using SKL DDI AUX regs instead of changing PSR_AUX regs definition (Rodrigo)
Signed-off-by: NSonika Jindal <sonika.jindal@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
[danvet: Drop the hunks to short-circuit sw tracking: We'd need to
push this down one level, and I don't fully trust the test coverage
yet to do so. So much prefer we pick a whitelist approach for the
cases we know work correctly.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When run as a timer, i915_hangcheck_elapsed() must adhere to all the
rules of running in a softirq context. This is advantageous to us as we
want to minimise the risk that a driver bug will prevent us from
detecting a hung GPU. However, that is irrelevant if the driver bug
prevents us from resetting and recovering. Still it is prudent not to
rely on mutexes inside the checker, but given the coarseness of
dev->struct_mutex doing so is extremely hard.

Give in and run from a work queue, i.e. outside of softirq.

v2: Use own workqueue to avoid deadlocks (Daniel)
    Cleanup commit msg and add comment to i915_queue_hangcheck() (Chris)

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Daniel Vetter <dnaiel.vetter@ffwll.chm>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
[danvet: Remove accidental kerneldoc comment starter, to appease the 0
day builder.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't have full atomic modeset support yet, but the "nuclear
pageflip" subset of functionality (i.e., plane operations only) should
be ready.  Allow the user to force atomic on for debug purposes, or for
fixed-purpose embedded devices that will only use atomic for plane
updates.

The term 'nuclear' is used here instead of 'atomic' to make it clear
that this doesn't allow full atomic modeset support, just a (very
useful) subset of the atomic functionality.

We'll drop the kernel parameter and unconditionally enable atomic in a
future patch once all of the necessary pieces are in.

v2:
 - Use module_param_named_unsafe() (Daniel)
 - Simplify comment on DRIVER_ATOMIC guard (Daniel)

v3:
 - Make the parameter "nuclear_pageflip" rather than just "nuclear"
   for clarity. (Ander)

v4:
 - Make the internal variable "nuclear_pageflip" as well as the
   command-line option. (Ander)
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NAnder Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>