wait_for_timelines is essentially the same loop as retiring requests
(with an extra timeout), so merge the two into one routine.

v2: i915_retire_requests_timeout and keep VT'd w/a as !interruptible

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-10-chris@chris-wilson.co.uk

Nothing inside the idle worker now requires struct_mutex, so we can
remove the indirection of using our own worker.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-9-chris@chris-wilson.co.uk

We don't need to hold struct_mutex now for retiring requests, so drop it
from i915_retire_requests() and i915_gem_wait_for_idle(), finally
removing I915_WAIT_LOCKED for good.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-8-chris@chris-wilson.co.uk

Now that we now longer need to guarantee that the active callback is
under the struct_mutex, we can lift it out of the i915_gem_park() and
into the engine parking itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-7-chris@chris-wilson.co.uk

Forgo the struct_mutex serialisation for i915_active, and interpose its
own mutex handling for active/retire.

This is a multi-layered sleight-of-hand. First, we had to ensure that no
active/retire callbacks accidentally inverted the mutex ordering rules,
nor assumed that they were themselves serialised by struct_mutex. More
challenging though, is the rule over updating elements of the active
rbtree. Instead of the whole i915_active now being serialised by
struct_mutex, allocations/rotations of the tree are serialised by the
i915_active.mutex and individual nodes are serialised by the caller
using the i915_timeline.mutex (we need to use nested spinlocks to
interact with the dma_fence callback lists).

The pain point here is that instead of a single mutex around execbuf, we
now have to take a mutex for active tracker (one for each vma, context,
etc) and a couple of spinlocks for each fence update. The improvement in
fine grained locking allowing for multiple concurrent clients
(eventually!) should be worth it in typical loads.

v2: Add some comments that barely elucidate anything :(

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-6-chris@chris-wilson.co.uk

As we need to use a mutex to serialise i915_active activation
(because we want to allow the callback to sleep), we need to push the
i915_active.retire into a worker callback in case we get need to retire
from an atomic context.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-5-chris@chris-wilson.co.uk

Replace the struct_mutex requirement for pinning the i915_vma with the
local vm->mutex instead. Note that the vm->mutex is tainted by the
shrinker (we require unbinding from inside fs-reclaim) and so we cannot
allocate while holding that mutex. Instead we have to preallocate
workers to do allocate and apply the PTE updates after we have we
reserved their slot in the drm_mm (using fences to order the PTE writes
with the GPU work and with later unbind).

In adding the asynchronous vma binding, one subtle requirement is to
avoid coupling the binding fence into the backing object->resv. That is
the asynchronous binding only applies to the vma timeline itself and not
to the pages as that is a more global timeline (the binding of one vma
does not need to be ordered with another vma, nor does the implicit GEM
fencing depend on a vma, only on writes to the backing store). Keeping
the vma binding distinct from the backing store timelines is verified by
a number of async gem_exec_fence and gem_exec_schedule tests. The way we
do this is quite simple, we keep the fence for the vma binding separate
and only wait on it as required, and never add it to the obj->resv
itself.

Another consequence in reducing the locking around the vma is the
destruction of the vma is no longer globally serialised by struct_mutex.
A natural solution would be to add a kref to i915_vma, but that requires
decoupling the reference cycles, possibly by introducing a new
i915_mm_pages object that is own by both obj->mm and vma->pages.
However, we have not taken that route due to the overshadowing lmem/ttm
discussions, and instead play a series of complicated games with
trylocks to (hopefully) ensure that only one destruction path is called!

v2: Add some commentary, and some helpers to reduce patch churn.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-4-chris@chris-wilson.co.uk

Since we cannot allocate underneath the vm->mutex (it is used in the
direct-reclaim paths), we need to shift the allocations off into a
mutexless worker with fence recursion prevention. To know when we need
this protection, we mark up the address spaces that do allocate before
insertion. In the future, we may wish to extend the async bind scheme to
more than just allocations.

v2: s/vm->bind_alloc/vm->bind_async_flags/

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-3-chris@chris-wilson.co.uk

The premise here is to simply avoiding having to acquire the vm->mutex
inside vma create/destroy to update the vm->unbound_lists, to avoid some
nasty lock recursions later.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-2-chris@chris-wilson.co.uk

A subset of 71724f70 ("drm/mm: Use helpers for drm_mm_node booleans")
in order to prepare drm-intel-next-queued for subsequent patches before
we can backmerge 71724f70

 itself.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004142226.13711-1-chris@chris-wilson.co.uk

The L3 cache remapping is stored as u32 elements, and we should ensure
that the user only supplies complete slice information(u32).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004105958.1741-1-chris@chris-wilson.co.uk

The CDCLK>=2*BCLK constraint applies to all generations since gen10.
Extend the constraint logic in audio get/put_power().

Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003085531.30990-2-kai.vehmanen@linux.intel.com

On platfroms with gen10+ display, driver must set the enable bit of
AUDIO_PIN_BUF_CTL register before transactions with the HDA controller
can proceed. Add setting this bit to the audio power up sequence.

Failing to do this resulted in errors during display audio codec probe,
and failures during resume from suspend.

Note: We may also need to disable the bit afterwards, but there are
still unresolved issues with that.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111214
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003085531.30990-1-kai.vehmanen@linux.intel.com

Add aux_busy_last_status to intel_dp. Don't bother with initializing to
all ones; the only difference is potentially missing logging for one
error case if the readout is all zeros.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002144138.7917-1-jani.nikula@intel.com

If we unwind the active requests, and on resubmission discover that we
intend to preempt the active contexts with themselves, simply skip the
ELSP submission.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003210100.22250-1-chris@chris-wilson.co.uk

The Thunderbolt PLL divider values on TGL differ from the ICL ones,
update the PLL parameter calculation function accordingly.

Bspec: 49204

v2:
- Remove unused refclk config. (José)

Cc: Jose Souza <jose.souza@intel.com>
Cc: Clinton A Taylor <clinton.a.taylor@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Mika Westerberg <mika.westerberg@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jose Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002204108.32242-1-imre.deak@intel.com

Unify on current common usage to allow repurposing drm_dbg() later. Fix
newlines while at it.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002145405.27848-2-jani.nikula@intel.com

Unify on current common usage to allow repurposing drm_err() later. Fix
newlines while at it.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002145405.27848-1-jani.nikula@intel.com

If execlists's lite-restore is based on the common GEM context tag
rather than the per-intel_context LRCA, then a context switch between
two intel_contexts on the same engine derived from the same GEM context
will perform a lite-restore instead of a full context switch. We can
exploit this by poisoning the ringbuffer of the first context and trying
to trick a simple RING_TAIL update (i.e. lite-restore)

v2: Also check what happens if preempt ce[0] with ce[1] (both instances
on the same engine from the same parent context) [Tvrtko]

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002183459.26614-1-chris@chris-wilson.co.uk

All the MG registers is based on the tc_port not port, so
MG_PHY_PORT_LN() was subtracting port and PORT_C what is very
fragile.
So replacing port to tc_port in all MG register macros and users
like we have for DKL.

Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001193729.123736-1-jose.souza@intel.com

Use BIT(pipe) for better legibility when populating the crtc_mask
for encoders.

Also remove the redundant possible_crtcs setup for the TV encoder.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190708162048.4286-11-ville.syrjala@linux.intel.com

Don't advertize non-exisiting crtcs in the encoder possible_crtcs
bitmask.

Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190708162048.4286-9-ville.syrjala@linux.intel.com

We repeat obj->ops->flags in our object checks, so pull that into its
own little helper for clarity.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002123014.1545-1-chris@chris-wilson.co.uk

For selftests, we desire repeatability and so prefer using a prng with
known seed over true randomness. Extract random_offset() as a selftest
utility that can take the prng state.

Suggested-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191002122430.23205-1-chris@chris-wilson.co.uk

I forgot to update the g4x sprite scaling stride check when GTT
remapping was introduced. The stride of the original framebuffer
is irrelevant when remapping is used and instead we want to check
the stride of the remapped view.

Also drop the duplicate width_bytes check. We already check that
a few lines earlier.

Fixes: df79cf44

 ("drm/i915: Store the final plane stride in plane_state")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190930183045.662-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

Drop the tv_mode NULL check since intel_tv_mode_find() never
actually returns NULL, and flip the condition around so that
the MODE_OK case is at the end, which is customary to all
the other .mode_valid() implementations.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001154629.11063-2-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>

When adding the max plane size checks to the .mode_valid() hooks
I naturally forgot about MST. Take care of that one as well.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: 2d20411e

 ("drm/i915: Don't advertise modes that exceed the max plane size")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001154629.11063-1-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>

Split out the code related to vga client and vgaarb all over the place
into new intel_vga.[ch]. No functional changes.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001152506.7854-1-jani.nikula@intel.com

Daniel Vetter uncovered a nasty cycle in using the mmu-notifiers to
invalidate userptr objects which also happen to be pulled into GGTT
mmaps. That is when we unbind the userptr object (on mmu invalidation),
we revoke all CPU mmaps, which may then recurse into mmu invalidation.

We looked for ways of breaking the cycle, but the revocation on
invalidation is required and cannot be avoided. The only solution we
could see was to not allow such GGTT bindings of userptr objects in the
first place. In practice, no one really wants to use a GGTT mmapping of
a CPU pointer...

Just before Daniel's explosive lockdep patches land in v5.4-rc1, we got
a genuine blip from CI:

<4>[  246.793958] ======================================================
<4>[  246.793972] WARNING: possible circular locking dependency detected
<4>[  246.793989] 5.3.0-gbd6c56f50d15-drmtip_372+ #1 Tainted: G     U
<4>[  246.794003] ------------------------------------------------------
<4>[  246.794017] kswapd0/145 is trying to acquire lock:
<4>[  246.794030] 000000003f565be6 (&dev->struct_mutex/1){+.+.}, at: userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[  246.794250]
                  but task is already holding lock:
<4>[  246.794263] 000000001799cef9 (&anon_vma->rwsem){++++}, at: page_lock_anon_vma_read+0xe6/0x2a0
<4>[  246.794291]
                  which lock already depends on the new lock.

<4>[  246.794307]
                  the existing dependency chain (in reverse order) is:
<4>[  246.794322]
                  -> #3 (&anon_vma->rwsem){++++}:
<4>[  246.794344]        down_write+0x33/0x70
<4>[  246.794357]        __vma_adjust+0x3d9/0x7b0
<4>[  246.794370]        __split_vma+0x16a/0x180
<4>[  246.794385]        mprotect_fixup+0x2a5/0x320
<4>[  246.794399]        do_mprotect_pkey+0x208/0x2e0
<4>[  246.794413]        __x64_sys_mprotect+0x16/0x20
<4>[  246.794429]        do_syscall_64+0x55/0x1c0
<4>[  246.794443]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[  246.794456]
                  -> #2 (&mapping->i_mmap_rwsem){++++}:
<4>[  246.794478]        down_write+0x33/0x70
<4>[  246.794493]        unmap_mapping_pages+0x48/0x130
<4>[  246.794519]        i915_vma_revoke_mmap+0x81/0x1b0 [i915]
<4>[  246.794519]        i915_vma_unbind+0x11d/0x4a0 [i915]
<4>[  246.794519]        i915_vma_destroy+0x31/0x300 [i915]
<4>[  246.794519]        __i915_gem_free_objects+0xb8/0x4b0 [i915]
<4>[  246.794519]        drm_file_free.part.0+0x1e6/0x290
<4>[  246.794519]        drm_release+0xa6/0xe0
<4>[  246.794519]        __fput+0xc2/0x250
<4>[  246.794519]        task_work_run+0x82/0xb0
<4>[  246.794519]        do_exit+0x35b/0xdb0
<4>[  246.794519]        do_group_exit+0x34/0xb0
<4>[  246.794519]        __x64_sys_exit_group+0xf/0x10
<4>[  246.794519]        do_syscall_64+0x55/0x1c0
<4>[  246.794519]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[  246.794519]
                  -> #1 (&vm->mutex){+.+.}:
<4>[  246.794519]        i915_gem_shrinker_taints_mutex+0x6d/0xe0 [i915]
<4>[  246.794519]        i915_address_space_init+0x9f/0x160 [i915]
<4>[  246.794519]        i915_ggtt_init_hw+0x55/0x170 [i915]
<4>[  246.794519]        i915_driver_probe+0xc9f/0x1620 [i915]
<4>[  246.794519]        i915_pci_probe+0x43/0x1b0 [i915]
<4>[  246.794519]        pci_device_probe+0x9e/0x120
<4>[  246.794519]        really_probe+0xea/0x3d0
<4>[  246.794519]        driver_probe_device+0x10b/0x120
<4>[  246.794519]        device_driver_attach+0x4a/0x50
<4>[  246.794519]        __driver_attach+0x97/0x130
<4>[  246.794519]        bus_for_each_dev+0x74/0xc0
<4>[  246.794519]        bus_add_driver+0x13f/0x210
<4>[  246.794519]        driver_register+0x56/0xe0
<4>[  246.794519]        do_one_initcall+0x58/0x300
<4>[  246.794519]        do_init_module+0x56/0x1f6
<4>[  246.794519]        load_module+0x25bd/0x2a40
<4>[  246.794519]        __se_sys_finit_module+0xd3/0xf0
<4>[  246.794519]        do_syscall_64+0x55/0x1c0
<4>[  246.794519]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[  246.794519]
                  -> #0 (&dev->struct_mutex/1){+.+.}:
<4>[  246.794519]        __lock_acquire+0x15d8/0x1e90
<4>[  246.794519]        lock_acquire+0xa6/0x1c0
<4>[  246.794519]        __mutex_lock+0x9d/0x9b0
<4>[  246.794519]        userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[  246.794519]        __mmu_notifier_invalidate_range_start+0x85/0x110
<4>[  246.794519]        try_to_unmap_one+0x76b/0x860
<4>[  246.794519]        rmap_walk_anon+0x104/0x280
<4>[  246.794519]        try_to_unmap+0xc0/0xf0
<4>[  246.794519]        shrink_page_list+0x561/0xc10
<4>[  246.794519]        shrink_inactive_list+0x220/0x440
<4>[  246.794519]        shrink_node_memcg+0x36e/0x740
<4>[  246.794519]        shrink_node+0xcb/0x490
<4>[  246.794519]        balance_pgdat+0x241/0x580
<4>[  246.794519]        kswapd+0x16c/0x530
<4>[  246.794519]        kthread+0x119/0x130
<4>[  246.794519]        ret_from_fork+0x24/0x50
<4>[  246.794519]
                  other info that might help us debug this:

<4>[  246.794519] Chain exists of:
                    &dev->struct_mutex/1 --> &mapping->i_mmap_rwsem --> &anon_vma->rwsem

<4>[  246.794519]  Possible unsafe locking scenario:

<4>[  246.794519]        CPU0                    CPU1
<4>[  246.794519]        ----                    ----
<4>[  246.794519]   lock(&anon_vma->rwsem);
<4>[  246.794519]                                lock(&mapping->i_mmap_rwsem);
<4>[  246.794519]                                lock(&anon_vma->rwsem);
<4>[  246.794519]   lock(&dev->struct_mutex/1);
<4>[  246.794519]
                   *** DEADLOCK ***

v2: Say no to mmap_ioctl

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111744
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111870
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190928082546.3473-1-chris@chris-wilson.co.uk

This patch avoids DP MST payload error message in dmesg, as it is trying
to update the payload to the disconnected DP MST device. After DP MST
device is disconnected we should not be updating the payload and
hence remove the error.

v2: Removed the connector status check and converted from error to debug.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111632
Signed-off-by: Srinivasan S <srinivasan.s@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1569371742-109402-1-git-send-email-srinivasan.s@intel.com

With deferring the breadcrumb signalling to the virtual engine (thanks
preempt-to-busy) we need to make sure the lists and irq-worker are ready
to send a signal.

[41958.710544] BUG: kernel NULL pointer dereference, address: 0000000000000000
[41958.710553] #PF: supervisor write access in kernel mode
[41958.710556] #PF: error_code(0x0002) - not-present page
[41958.710558] PGD 0 P4D 0
[41958.710562] Oops: 0002 [#1] SMP
[41958.710565] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U            5.3.0+ #207
[41958.710568] Hardware name: Intel Corporation NUC7i5BNK/NUC7i5BNB, BIOS BNKBL357.86A.0052.2017.0918.1346 09/18/2017
[41958.710602] RIP: 0010:i915_request_enable_breadcrumb+0xe1/0x130 [i915]
[41958.710605] Code: 8b 44 24 30 48 89 41 08 48 89 08 48 8b 85 98 01 00 00 48 8d 8d 90 01 00 00 48 89 95 98 01 00 00 49 89 4c 24 28 49 89 44 24 30 <48> 89 10 f0 80 4b 30 10 c6 85 88 01 00 00 00 e9 1a ff ff ff 48 83
[41958.710609] RSP: 0018:ffffc90000003de0 EFLAGS: 00010046
[41958.710612] RAX: 0000000000000000 RBX: ffff888735424480 RCX: ffff8887cddb2190
[41958.710614] RDX: ffff8887cddb3570 RSI: ffff888850362190 RDI: ffff8887cddb2188
[41958.710617] RBP: ffff8887cddb2000 R08: ffff8888503624a8 R09: 0000000000000100
[41958.710619] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8887cddb3548
[41958.710622] R13: 0000000000000000 R14: 0000000000000046 R15: ffff888850362070
[41958.710625] FS:  0000000000000000(0000) GS:ffff88885ea00000(0000) knlGS:0000000000000000
[41958.710628] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[41958.710630] CR2: 0000000000000000 CR3: 0000000002c09002 CR4: 00000000001606f0
[41958.710633] Call Trace:
[41958.710636]  <IRQ>
[41958.710668]  __i915_request_submit+0x12b/0x160 [i915]
[41958.710693]  virtual_submit_request+0x67/0x120 [i915]
[41958.710720]  __unwind_incomplete_requests+0x131/0x170 [i915]
[41958.710744]  execlists_dequeue+0xb40/0xe00 [i915]
[41958.710771]  execlists_submission_tasklet+0x10f/0x150 [i915]
[41958.710776]  tasklet_action_common.isra.17+0x41/0xa0
[41958.710781]  __do_softirq+0xc8/0x221
[41958.710785]  irq_exit+0xa6/0xb0
[41958.710788]  smp_apic_timer_interrupt+0x4d/0x80
[41958.710791]  apic_timer_interrupt+0xf/0x20
[41958.710794]  </IRQ>

Fixes: cb2377a9

 ("drm/i915: Fixup preempt-to-busy vs reset of a virtual request")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191001103518.9113-1-chris@chris-wilson.co.uk

Unwedging the GPU requires a successful GPU reset before we restore the
default submission, or else we may see residual context switch events
that we were not expecting.

v2: Pull in the special-case reset_clobbers_display, and explain why it
should be safe in the context of unwedging.

v3: Just forget all about resets before unwedging if it will clobber the
display; risk it all.

Reported-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20190927160335.10622-1-chris@chris-wilson.co.uk

We currently test context switching on each engine as a basic stress
test (just verifying that nothing explodes if we execute 2 requests from
different contexts sequentially). What we have not tested is what
happens if we try and do so on all available engines simultaneously,
putting our SW and the HW under the maximal stress.

v2: Clone the set of engines from the first context into the secondary
contexts.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190930144919.27992-1-chris@chris-wilson.co.uk

For those mock tests that may wish to pretend triggering a GPU reset and
processing the cleanup.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927211749.2181-3-chris@chris-wilson.co.uk

On systems that have no runtime-pm, we mark the wakeref as being -1. We
therefore cannot use that value for the mock-gt indicator, so opt for
-ENODEV instead. The wakeref should never be an error value -- one
hopes!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927211749.2181-2-chris@chris-wilson.co.uk

As we execute GPU resets on a gt/ basis, and use the intel_gt as the
primary for all other reset functions, also use it for the has-reset?
predicates. Gradually simplifying the churn of pointers.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927211749.2181-1-chris@chris-wilson.co.uk

If we are mocking the device, skip trying to sanitize the pm HW state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927210646.29664-1-chris@chris-wilson.co.uk

i915_gem_init_early doesn't need to return anything.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927173409.31175-3-matthew.auld@intel.com

Explosions during early driver init on the error path. Make sure we fail
gracefully.

[ 9547.672258] BUG: kernel NULL pointer dereference, address: 000000000000007c
[ 9547.672288] #PF: supervisor read access in kernel mode
[ 9547.672292] #PF: error_code(0x0000) - not-present page
[ 9547.672296] PGD 8000000846b41067 P4D 8000000846b41067 PUD 797034067 PMD 0
[ 9547.672303] Oops: 0000 [#1] SMP PTI
[ 9547.672307] CPU: 1 PID: 25634 Comm: i915_selftest Tainted: G     U            5.3.0-rc8+ #73
[ 9547.672313] Hardware name:  /NUC6i7KYB, BIOS KYSKLi70.86A.0050.2017.0831.1924 08/31/2017
[ 9547.672395] RIP: 0010:intel_context_unpin+0x9/0x100 [i915]
[ 9547.672400] Code: 6b 60 00 e9 17 ff ff ff bd fc ff ff ff e9 7c ff ff ff 66 66 2e 0f 1f 84 00 00 00 00
 00 0f 1f 40 00 0f 1f 44 00 00 41 54 55 53 <8b> 47 7c 83 f8 01 74 26 8d 48 ff f0 0f b1 4f 7c 48 8d 57 7c
 75 05
[ 9547.672413] RSP: 0018:ffffae8ac24ff878 EFLAGS: 00010246
[ 9547.672417] RAX: ffff944a1b7842d0 RBX: ffff944a1b784000 RCX: ffff944a12dd6fa8
[ 9547.672422] RDX: ffff944a1b7842c0 RSI: ffff944a12dd5328 RDI: 0000000000000000
[ 9547.672428] RBP: 0000000000000000 R08: ffff944a11e5d840 R09: 0000000000000000
[ 9547.672433] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[ 9547.672438] R13: ffffffffc11aaf00 R14: 00000000ffffffe4 R15: ffff944a0e29bf38
[ 9547.672443] FS:  00007fc259b88ac0(0000) GS:ffff944a1f880000(0000) knlGS:0000000000000000
[ 9547.672449] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9547.672454] CR2: 000000000000007c CR3: 0000000853346003 CR4: 00000000003606e0
[ 9547.672459] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 9547.672464] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 9547.672469] Call Trace:
[ 9547.672518]  intel_engine_cleanup_common+0xe3/0x270 [i915]
[ 9547.672567]  execlists_destroy+0xe/0x30 [i915]
[ 9547.672669]  intel_engines_init+0x94/0xf0 [i915]
[ 9547.672749]  i915_gem_init+0x191/0x950 [i915]

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190927173409.31175-2-matthew.auld@intel.com

Now that TC support was added, initialize DDIs.

Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190926210659.56317-4-jose.souza@intel.com