Fixed the stepping check on WaDisableDgMirrorFixInHalfSliceChicken5
to be for the correct SOC (Skylake)
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In DRM/KMS we are lacking a good way to deal with tiled/compressed
formats.  Especially in the case of dmabuf/prime buffer sharing, where
we cannot always rely on under-the-hood flags passed to driver specific
gem-create ioctl to pass around these extra flags.

The proposal is to add a per-plane format modifier.  This allows to, if
necessary, use different tiling patters for sub-sampled planes, etc.
The format modifiers are added at the end of the ioctl struct, so for
legacy userspace it will be zero padded.

v1: original
v1.5: increase modifier to 64b

v2: Incorporate review comments from the big thread, plus a few more.

- Add a getcap so that userspace doesn't have to jump through hoops.
- Allow modifiers only when a flag is set. That way drivers know when
  they're dealing with old userspace and need to fish out e.g. tiling
  from other information.
- After rolling out checks for ->modifier to all drivers I've decided
  that this is way too fragile and needs an explicit opt-in flag. So
  do that instead.
- Add a define (just for documentation really) for the "NONE"
  modifier. Imo we don't need to add mask #defines since drivers
  really should only do exact matches against values defined with
  fourcc_mod_code.
- Drop the Samsung tiling modifier on Rob's request since he's not yet
  sure whether that one is accurate.

v3:
- Also add a new ->modifier[] array to struct drm_framebuffer and fill
  it in drm_helper_mode_fill_fb_struct. Requested by Tvrkto Uruslin.
- Remove TODO in comment and add code comment that modifiers should be
  properly documented, requested by Rob.

Cc: Rob Clark <robdclark@gmail.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Daniel Stone <daniel@fooishbar.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Michel Dänzer <michel@daenzer.net>
Signed-off-by: Rob Clark <robdclark@gmail.com> (v1.5)
Reviewed-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NDaniel Stone <daniels@collabora.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The current code will both potentially print a WARN, and setup part of
the PPGTT structure. Neither of these harm the current code, it is
simply for clarity, and to perhaps prevent later bugs, or weird
debug messages.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In gen8, 32b PPGTT has always had one "pdp" (it doesn't actually have
one, but it resembles having one). The #define was confusing as is, and
using "PDPE" is a much better description.

sed -i 's/GEN8_LEGACY_PDPS/GEN8_LEGACY_PDPES/' drivers/gpu/drm/i915/*.[ch]

It also matches the x86 pagetable terminology:
PTE  = Page Table Entry - pagetable level 1 page
PDE  = Page Directory Entry - pagetable level 2 page
PDPE = Page Directory Pointer Entry - pagetable level 3 page

And in the near future (for 48b addressing):
PML4E = Page Map Level 4 Entry

v2: Expanded information about Page Directory/Table nomenclature.

Cc: Daniel Vetter <daniel@ffwll.ch>
CC: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Don't add WaHdcDisableFetchWhenMasked. Add stepping check for
WaForceEnableNonCoherent
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move Wa4x4STCOptimizationDisable to gen9_init_workarounds

v2: rebase
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move WaEnableYV12BugFixInHalfSliceChicken7 to gen9_init_workarounds

v2: Add stepping check.
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Add stepping check for WaDisableSDEUnitClockGating.
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Rebase.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This one doesn't have one of these nice cryptic names unfortunately.

v2: Added missing register bitmap
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move WaDisableDgMirrorFixInHalfSliceChicken5 to gen9_init_workarounds

v2: Added stepping check

v3: Removed unused register bitmap
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
[danvet: Bikesheds.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Dont add WaDisableThreadStallDopClockGating as not SKL WA. (Found
by Damien Lespiau)
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Bikeshed commit message a bit as per Damien's suggestions.]
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>

Add framework for gen 9 HW WAs

v1: Changed SOC specific WA function to gen 9 common function (Req: Damien Lespiau)
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't want to end up in a state where we track that the pipe has its
primary plane enabled when primary plane registers are programmed with
values that look possible but the plane actually disabled.

Refuse to read out the fb state when the primary plane isn't enabled.
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Right now, we get a warning when taking over the firmware fb:

  [drm:drm_atomic_plane_check] FB set but no CRTC

with the following backtrace:

  [<ffffffffa010339d>] drm_atomic_check_only+0x35d/0x510 [drm]
  [<ffffffffa0103567>] drm_atomic_commit+0x17/0x60 [drm]
  [<ffffffffa00a6ccd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
  [<ffffffffa00f1fed>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
  [<ffffffffa00a8a1b>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
  [<ffffffffa00aa969>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
  [<ffffffffa00aa9e2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
  [<ffffffffa050a71a>] intel_fbdev_set_par+0x1a/0x60 [i915]
  [<ffffffff813ad444>] fbcon_init+0x4f4/0x580

That's because we update the plane state with the fb from the firmware, but we
never associate the plane to that CRTC.

We don't quite have the full DRM take over from HW state just yet, so
fake enough of the plane atomic state to pass the checks.

v2: Fix the state on which we set the CRTC in the case we're sharing the
    initial fb with another pipe. (Matt)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

At the moment we use crtc->base.primary->fb to hold the initial
framebuffer allocation, disregarding if it's valid or not.

This lead to believe we were actually updating the fb at this point, but
it's not true and we haven't even called drm_framebuffer_init() on this
fb.

Instead, let's store the state in struct intel_initial_plane_config
until we know we can reuse that framebuffer.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Tvrtko noticed a new warning on boot:

  WARNING: CPU: 1 PID: 353 at include/linux/kref.h:47 drm_framebuffer_reference+0x6c/0x80 [drm]()
  Call Trace:
  [<ffffffff8161f10c>] dump_stack+0x4f/0x7b
  [<ffffffff81052caa>] warn_slowpath_common+0xaa/0xd0
  [<ffffffff81052d8a>] warn_slowpath_null+0x1a/0x20
  [<ffffffffa00d035c>] drm_framebuffer_reference+0x6c/0x80 [drm]
  [<ffffffffa01c0df7>] update_state_fb.isra.54+0x47/0x50 [i915]
  [<ffffffffa01ccd5c>] skylake_get_initial_plane_config+0x93c/0x950 [i915]
  [<ffffffffa01e8721>] intel_modeset_init+0x1551/0x17c0 [i915]
  [<ffffffffa02476e0>] i915_driver_load+0xed0/0x11e0 [i915]
  [<ffffffff81627aa1>] ? _raw_spin_unlock_irqrestore+0x51/0x70
  [<ffffffffa00ca8b7>] drm_dev_register+0x77/0x110 [drm]
  [<ffffffffa00cda3b>] drm_get_pci_dev+0x11b/0x1f0 [drm]
  [<ffffffff81098e3d>] ? trace_hardirqs_on+0xd/0x10
  [<ffffffff81627aa1>] ? _raw_spin_unlock_irqrestore+0x51/0x70
  [<ffffffffa0145276>] i915_pci_probe+0x56/0x60 [i915]
  [<ffffffff813ad59c>] pci_device_probe+0x7c/0x100
  [<ffffffff81466aad>] driver_probe_device+0x16d/0x380

We cannot take a reference at this point, not before
intel_framebuffer_init() and the underlying drm_framebuffer_init().

Introduced in:

  commit 706dc7b549175e47f23e913b7f1e52874a7d0f56
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Feb 3 13:10:04 2015 -0800

      drm/i915: Ensure plane->state->fb stays in sync with plane->fb

v2: Don't move update_state_fb(). It was moved around because I
    originally put update_state_fb() in intel_alloc_plane_obj() before
    finding a better place. (Matt)
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Reported-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The code look slightly better this way and will ease the next commit,
changing where we take the fb pointer from.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

update_state_fb() at the end of intel_find_plane_obj() is misleading as
it leads us to believe the update is done for all code path.

A successful call to intel_alloc_plane_obj() will return and
update_state_fb() is then only needed when we share a fb from another
CRTC. Put the update() function there then.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
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>

v2: leave intel_skylake_info alone (Rodrigo, Daniel)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This patch implements core logic of SKL display power well.

v2: Addressed Imre's comments
	- Added respective DDIs under power well #1 and #2
	- Simplified repetitive code in power well programming

v3: Implemented Imre's comments
	- Further simplified power well programming
	- Made sure that PW 1 is enabled prior to PW 2

v4: Fix minor conflict with the the cherryview support (Damien)

v5: Add the PLL power domain to the always on power well (Damien)

v6: Disable BIOS power well (Imre)
    Use power well data for comparison (Imre)
    Put the PLL power domain into PW1 as its needed for CDCLK (Satheesh,
    Damien)

v7: Addressed Imre's comments
  - Lowered the time out to 1ms
  - Added parantheses in macro
  - Moved debug message and fixed wait_for interval

v8:
  - Add a WARN() when swiching on an unknown power well (Imre, done by Damien)
  - Whitespace fixes (spaces instead of tabs) (Damien)

v9: (Imre, done by Damien)
  - Merge the register definitions with this patch
  - Merge the MISC IO power well in this patch

v10: (Imre, done by Damien)

  - Define the Misc I/O power domains to be the power well 1 ones as Misc I/O
    needs to be enabled with PW1
  - Added Transcoder A and VGA domains to PW 2
  - Remove the MISC_IO power domains as well in the the always on
    domains definition
  - Move Misc I/O power well at the top of the power well list so it's turned
    on right after PW1.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: Satheeshakrishna M <satheeshakrishna.m@intel.com> (v3,v6,v7)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

plane->state->fb and plane->fb should always reference the same FB so
that atomic and legacy codepaths have the same view of display state.
In commit

        commit db068420560511de80ac59222644f2bdf278c3d5
        Author: Matt Roper <matthew.d.roper@intel.com>
        Date:   Fri Jan 30 16:22:36 2015 -0800

            drm/i915: Keep plane->state updated on pageflip

we already fixed one case where these two pointers could get out of
sync.  However it turns out there are a few other places (mainly dealing
with initial FB setup at boot) that directly set plane->fb and neglect
to update plane->state->fb.  If we never do a successful update through
the atomic pipeline, the RmFB cleanup code will look at the
plane->state->fb pointer, which has never actually been set to a
legitimate value, and try to clean it up, leading to BUG's.

Add a quick helper function to synchronize plane->state->fb with
plane->fb (and update reference counts accordingly) and call it
everywhere the driver tries to manually set plane->fb outside of the
atomic pipeline.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88909Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We already track this in the intel_info struct.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
[danvet: Make the commit message a bit less terse.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This isuue got introduced in -

commit 24ee0e64
Author: Gaurav K Singh <gaurav.k.singh@intel.com>
Date:   Fri Dec 5 14:24:21 2014 +0530

    drm/i915: Update the DSI enable path to support dual
Signed-off-by: NShobhit Kumar <shobhit.kumar@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
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>

Daniel Vetter spotted a bug while reviewing some of my refactoring in this
are of the code. I'll quote:

"""
> @@ -9764,6 +9768,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
>  	work->event = event;
>  	work->crtc = crtc;
>  	work->old_fb_obj = intel_fb_obj(old_fb);
> +	work->old_tiling_mode = to_intel_framebuffer(old_fb)->tiling_mode;

Hm, that's actually an interesting bugfix - currently userspace could be
sneaky and destroy the old fb immediately after the flip completes and the
change the tiling of the underlying object before the unpin work had a
chance to run (needs some fudgin with rt prios to starve workers to make
this work though).

Imo the right fix is to hold a reference onto the fb and not the
underlying gem object. With that tiling is guaranteed not to change.
"""

This patch tries to implement the above proposed change.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There are two sets of helper functions provided by the DRM core that can
implement the .update_plane() and .disable_plane() hooks in terms of a
driver's atomic entrypoints.  The transitional helpers (which we have
been using so far) create a plane state and then use the plane's atomic
entrypoints to perform the atomic begin/check/prepare/commit/finish
sequence on that single plane only.  The full atomic helpers create a
top-level atomic state (which is capable of holding multiple object
states for planes, crtc's, and/or connectors) and then passes the
top-level atomic state through the full "atomic modeset" pipeline.

Switching from the transitional to full helpers here shouldn't result in
any functional change, but will enable us to exercise/test more of the
internal atomic pipeline with the legacy API's used by existing
applications.
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Until all drivers have transitioned to atomic, the framebuffer
associated with a plane is tracked in both plane->fb (for legacy) and
plane->state->fb (for all the new atomic codeflow).  All of our modeset
and plane updates use drm_plane->update_plane(), so in theory plane->fb
and plane->state->fb should always stay in sync and point at the same
thing for i915.  However we forgot about the pageflip ioctl case, which
currently only updates plane->fb and leaves plane->state->fb at a stale
value.

Surprisingly, this doesn't cause any real problems at the moment since
internally we use the plane->fb pointer in most of the places that
matter, and on the next .update_plane() call, we use plane->fb to figure
out which framebuffer to cleanup.  However when we switch to the full
atomic helpers for update_plane()/disable_plane(), those helpers use
plane->state->fb to figure out which framebuffer to cleanup, so not
having updated the plane->state->fb pointer causes things to blow up
following a pageflip ioctl.

The fix here is to just make sure we update plane->state->fb at the same
time we update plane->fb in the pageflip ioctl.
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

You can _never_ assert that a lock is not held, except in some very
restricted corner cases where it's guranteed that your code is running
single-threade (e.g. driver load before you've published any pointers
leading to that lock).

In addition the early return breaks a bunch of testcases since with
highly concurrent hangcheck stress tests the reset fails to work and
the test doesn't recover and time out.

This regression has been introduced in

commit b8d24a06
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Wed Jan 28 17:03:14 2015 +0200

    drm/i915: Remove nested work in gpu error handling

Aside: It is possible to check whether a given task doesn't hold a
lock, but only when lockdep is enabled, using the lockdep_assert_held
stuff.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88908Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

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

The get_config() functions for ddi and dp_mst, used to read the value
of cpu_transcoder from the crtc->config instead of the state passed as
an argument. On the hardware state readout path, that happens to work
since the proper value is written to it before encoder->get_config() is
called. However, in the check_crtc() path, the state will be read from
the cpu_transcoder in the software tracking, instead of the one just
read out from hw. Using the field in the supplied intel_crtc_state
should do the right thing in both cases.

v2: Fix intel_ddi_get_config() too. (Ander)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Remove request from list before unreferencing it, in case it's actually
the only reference. (Found by Tvrtko Ursulin)

This issue has been most likely introduced in

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

    drm/i915: Subsume intel_ctx_submit_request in to drm_i915_gem_request
Signed-off-by: NNick Hoath <nicholas.hoath@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This simplifies __intel_set_mode() a little.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The checking for ack and also any subsequent mmio access
will serialize with setting the forcewake bit. Drop the
posting read as superfluous.

Note that in the put side we still want to keep the posting read
as it will ensure that the hw sees our forcewake release in a
timely manner and doesn't keep the hw powered up.

Comment from Chris:

On Wed, Jan 28, 2015 at 05:54:14PM +0200, Mika Kuoppala wrote:
> Ville Syrjälä <ville.syrjala@linux.intel.com> writes:
> > IIRC the posting read from same cache line actually fixed real bugs. So
> > I'm a bit worried about dropping them. But I suppose it's possible only
> > the _put side was important for those bugs.
>
> I found these:
>
> commit 6af2d180
> Author: Daniel Vetter <daniel.vetter@ffwll.ch>
> Date:   Thu Jul 26 16:24:50 2012 +0200
>
>     drm/i915: fix forcewake related hangs on snb
>
> commit 8dee3eea
> Author: Ben Widawsky <ben@bwidawsk.net>
> Date:   Sat Sep 1 22:59:50 2012 -0700
>
>     drm/i915: Never read FORCEWAKE
>
> https://bugs.freedesktop.org/show_bug.cgi?id=51738
> https://bugs.freedesktop.org/show_bug.cgi?id=52424
>
> The snb here seems to survive gem_dummy_reloc_loop and
> gem_ring_sync_loop in here with the get side posting removed.

Note that we kept the once associated with #52424, but judging by my
comments in #51738 the posting read is just a band aid anyway as a full
mb() itself was not adequate.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: paste relevant review discussion in.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intel_uncore_early_sanitize() will reset the forcewake registers. When
forcewake domains were introduced, the domain init was done after the
sanitization of the forcewake registers. And as the resetting of
registers use the domain accessors, we tried to reset the forcewake
registers with unitialized forcewake domains and failed.

Fix this by sanitizing after all the domains have been initialized. Do
per domain clearing of forcewake register on domain init so that
IVB can do early access to ECOBUS do determine the final configuration.

This regression was introduced in

commit 05a2fb15
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Mon Jan 19 16:20:43 2015 +0200

    drm/i915: Consolidate forcewake code

v2: Carve out ellc detect, fw_domain_reset for ivb/ecobus (Chris)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88805
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: NOlof Johansson <olof@lixom.net>
Tested-by: Darren Hart <dvhart@linux.intel.com> (v1)
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>

Move the CHV check into vlv_set_rps_idle() to simplify the caller a bit.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
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>