Taking a PM reference to prevent intel_gt_wait_for_idle from short
circuiting while any user context has scheduling enabled. Returning GT
idle when it is not can cause all sorts of issues throughout the stack.

v2:
 (Daniel Vetter)
  - Add might_lock annotations to pin / unpin function
v3:
 (CI)
  - Drop intel_engine_pm_might_put from unpin path as an async put is
    used
v4:
 (John Harrison)
  - Make intel_engine_pm_might_get/put work with GuC virtual engines
  - Update commit message
v5:
  - Update commit message again
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-4-matthew.brost@intel.com

Taking a PM reference to prevent intel_gt_wait_for_idle from short
circuiting while a deregister context H2G is in flight. To do this must
issue the deregister H2G from a worker as context can be destroyed from
an atomic context and taking GT PM ref blows up. Previously we took a
runtime PM from this atomic context which worked but will stop working
once runtime pm autosuspend in enabled.

So this patch is two fold, stop intel_gt_wait_for_idle from short
circuting and fix runtime pm autosuspend.

v2:
 (John Harrison)
  - Split structure changes out in different patch
 (Tvrtko)
  - Don't drop lock in deregister_destroyed_contexts
v3:
 (John Harrison)
  - Flush destroyed contexts before destroying context reg pool
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-3-matthew.brost@intel.com

Move guc_id allocation under submission state sub-struct as a future
patch will reuse the spin lock as a global submission state lock. Moving
this into sub-struct makes ownership of fields / lock clear.

v2:
 (Docs)
  - Add comment for submission_state sub-structure
v3:
 (John Harrison)
  - Fixup a few comments
v4:
 (John Harrison)
  - Fix typo
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-2-matthew.brost@intel.com

Pinned contexts, like the migrate contexts need reset after resume
since their context image may have been lost. Also the GuC needs to
register pinned contexts.

Add a list to struct intel_engine_cs where we add all pinned contexts on
creation, and traverse that list at resume time to reset the pinned
contexts.

This fixes the kms_pipe_crc_basic@suspend-read-crc-pipe-a selftest for now,
but proper LMEM backup / restore is needed for full suspend functionality.
However, note that even with full LMEM backup / restore it may be
desirable to keep the reset since backing up the migrate context images
must happen using memcpy() after the migrate context has become inactive,
and for performance- and other reasons we want to avoid memcpy() from
LMEM.

Also traverse the list at guc_init_lrc_mapping() calling
guc_kernel_context_pin() for the pinned contexts, like is already done
for the kernel context.

v2:
- Don't reset the contexts on each __engine_unpark() but rather at
  resume time (Chris Wilson).
v3:
- Reset contexts in the engine sanitize callback. (Chris Wilson)

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Brost Matthew <matthew.brost@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NThomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210922062527.865433-6-thomas.hellstrom@linux.intel.com

Add GuC kernel doc for all structures added thus far for GuC submission
and update the main GuC submission section with the new interface
details.

v2:
 - Drop guc_active.lock DOC
v3:
 - Fixup a few kernel doc comments (Daniele)
v4 (Daniele):
 - Implement doc suggestions from John
 - Add kerneldoc for all members of the GuC structure and pull the file
   in i915.rst
v5 (Daniele):
 - Implement new doc suggestions from John
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-24-matthew.brost@intel.com

Now that we have locking hierarchy of sched_engine->lock ->
ce->guc_state everything from guc_active can be moved into guc_state and
protected the guc_state.lock.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-23-matthew.brost@intel.com

To make ownership of locking clear move fields (guc_id, guc_id_ref,
guc_id_link) to sub structure guc_id in intel_context.
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-22-matthew.brost@intel.com

Move GuC management fields in context under guc_active struct as this is
where the lock that protects theses fields lives. Also only set guc_prio
field once during context init.

v2:
 (Daniele)
  - set CONTEXT_SET_INIT
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-21-matthew.brost@intel.com

Drop pin count check trick between a sched_disable and re-pin, now rely
on the lock and counter of the number of committed requests to determine
if scheduling should be disabled on the context.
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-20-matthew.brost@intel.com

Lock the xarray and take ref to the context if needed.

v2:
 (Checkpatch)
  - Add new line after declaration
 (Daniel Vetter)
  - Correct put / get accounting in xa_for_loops
v3:
 (Checkpatch)
  - Extra new line
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-19-matthew.brost@intel.com

Rework and simplify the locking with GuC subission. Drop
sched_state_no_lock and move all fields under the guc_state.sched_state
and protect all these fields with guc_state.lock . This requires
changing the locking hierarchy from guc_state.lock -> sched_engine.lock
to sched_engine.lock -> guc_state.lock.

v2:
 (Daniele)
  - Don't check fields outside of lock during sched disable, check less
    fields within lock as some of the outside are no longer needed
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-18-matthew.brost@intel.com

Move guc_blocked fence to struct guc_state as the lock which protects
the fence lives there.

s/ce->guc_blocked/ce->guc_state.blocked/g

v2:
 (Daniele)
  - s/blocked_fence/blocked/g
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-17-matthew.brost@intel.com

A subsequent patch will flip the locking hierarchy from
ce->guc_state.lock -> sched_engine->lock to sched_engine->lock ->
ce->guc_state.lock. As such we need to release the submit fence for a
request from an IRQ to break a lock inversion - i.e. the fence must be
release went holding ce->guc_state.lock and the releasing of the can
acquire sched_engine->lock.

v2:
 (Daniele)
  - Delete request from list before calling irq_work_queue
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-16-matthew.brost@intel.com

Reset LRC descriptor if a context register returns -ENODEV as this means
we are mid-reset.

Fixes: eb5e7da7 ("drm/i915/guc: Reset implementation for new GuC interface")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-15-matthew.brost@intel.com

Before we did some clever tricks to not use the a lock when touching
guc_state.sched_state in certain cases. Don't do that, enforce the use
of the lock.

v2:
 (kernel test robo )
  - Add __maybe_unused to sched_state_is_init()

v3: rebase after the unused code path removal has been moved to an
earlier patch.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reported-by: Nkernel test robot <lkp@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-14-matthew.brost@intel.com

A context can get destroyed after cancelling a request, if a context or
GT reset occurs, so take a reference to context when cancelling a
request.

Fixes: 62eaf0ae ("drm/i915/guc: Support request cancellation")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-13-matthew.brost@intel.com

While debugging an issue with full GT resets I went down a rabbit hole
thinking the scrubbing of lost G2H wasn't working correctly. This proved
to be incorrect as this was working just fine but this chase inspired me
to write a selftest to prove that this works. This simple selftest
injects errors dropping various G2H and then issues a full GT reset
proving that the scrubbing of these G2H doesn't blow up.

v2:
 (Daniel Vetter)
  - Use ifdef instead of macros for selftests
v3:
 (Checkpatch)
  - A space after 'switch' statement
v4:
 (Daniele)
  - A comment saying GT won't idle if G2H are lost
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-12-matthew.brost@intel.com

When unblocking a context, do not enable scheduling if the context is
banned, guc_id invalid, or not registered.

v2:
 (Daniele)
  - Add helper for unblock

Fixes: 62eaf0ae ("drm/i915/guc: Support request cancellation")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-10-matthew.brost@intel.com

Kick tasklet after queuing a request so it submitted in a timely manner.

Fixes: 3a4cdf19 ("drm/i915/guc: Implement GuC context operations for new inteface")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-9-matthew.brost@intel.com

If the context is reset as a result of the request cancellation the
context reset G2H is received after schedule disable done G2H which is
the wrong order. The schedule disable done G2H release the waiting
request cancellation code which resubmits the context. This races
with the context reset G2H which also wants to resubmit the context but
in this case it really should be a NOP as request cancellation code owns
the resubmit. Use some clever tricks of checking the context state to
seal this race until the GuC firmware is fixed.

v2:
 (Checkpatch)
  - Fix typos
v3:
 (Daniele)
  - State that is a bug in the GuC firmware

Fixes: 62eaf0ae ("drm/i915/guc: Support request cancellation")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-7-matthew.brost@intel.com

Don't drop ce->guc_active.lock when unwinding a context after reset.
At one point we had to drop this because of a lock inversion but that is
no longer the case. It is much safer to hold the lock so let's do that.

Fixes: eb5e7da7 ("drm/i915/guc: Reset implementation for new GuC interface")
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-5-matthew.brost@intel.com

When unwinding requests on a reset context, if other requests in the
context are in the priority list the requests could be resubmitted out
of seqno order. Traverse the list of active requests in reverse and
append to the head of the priority list to fix this.

Fixes: eb5e7da7 ("drm/i915/guc: Reset implementation for new GuC interface")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-4-matthew.brost@intel.com

A small race that could result in incorrect accounting of the number
of outstanding G2H. Basically prior to this patch we did not increment
the number of outstanding G2H if we encoutered a GT reset while sending
a H2G. This was incorrect as the context state had already been updated
to anticipate a G2H response thus the counter should be incremented.

As part of this change we remove a legacy (now unused) path that was the
last caller requiring a G2H response that was not guaranteed to loop.
This allows us to simplify the accounting as we don't need to handle the
case where the send fails due to the channel being busy.

Also always use helper when decrementing this value.

v2 (Daniele): update GEM_BUG_ON check, pull in dead code removal from
later patch, remove loop param from context_deregister.

Fixes: f4eb1f3f ("drm/i915/guc: Ensure G2H response has space in buffer")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-3-matthew.brost@intel.com

Prior to this patch the blocked context counter was cleared on
init_sched_state (used during registering a context & resets) which is
incorrect. This state needs to be persistent or the counter can read the
incorrect value resulting in scheduling never getting enabled again.

Fixes: 62eaf0ae ("drm/i915/guc: Support request cancellation")
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-2-matthew.brost@intel.com

The assumption when it was added was that GT would not be
holding any gt_pm references. However, uc_init is called
from gt_init_hw, which holds a forcewake ref. If SLPC
enable fails, we will still be holding this ref, which will
result in the BUG_ON.
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NVinay Belgaumkar <vinay.belgaumkar@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730202119.23810-7-vinay.belgaumkar@intel.com

Unblock GuC submission on Gen11+ platforms.

v2:
 (Martin Peres / John H)
  - Delete debug message when GuC is disabled by default on certain
    platforms
Signed-off-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-34-matthew.brost@intel.com

Implement a simple static mapping algorithm of the i915 priority levels
(int, -1k to 1k exposed to user) to the 4 GuC levels. Mapping is as
follows:

i915 level < 0          -> GuC low level     (3)
i915 level == 0         -> GuC normal level  (2)
i915 level < INT_MAX    -> GuC high level    (1)
i915 level == INT_MAX   -> GuC highest level (0)

We believe this mapping should cover the UMD use cases (3 distinct user
levels + 1 kernel level).

In addition to static mapping, a simple counter system is attached to
each context tracking the number of requests inflight on the context at
each level. This is needed as the GuC levels are per context while in
the i915 levels are per request.

v2:
 (Daniele)
  - Add BUILD_BUG_ON to enforce ordering of priority levels
  - Add missing lockdep to guc_prio_fini
  - Check for return before setting context registered flag
  - Map DISPLAY priority or higher to highest guc prio
  - Update comment for guc_prio
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-33-matthew.brost@intel.com

When GuC submission is enabled, the GuC controls engine resets. Rather
than explicitly triggering a reset, the driver must submit a hanging
context to GuC and wait for the reset to occur.
Signed-off-by: NRahul Kumar Singh <rahul.kumar.singh@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-28-matthew.brost@intel.com

This adds GuC backend support for i915_request_cancel(), which in turn
makes CONFIG_DRM_I915_REQUEST_TIMEOUT work.

This implementation makes use of fence while there are likely simplier
options. A fence was chosen because of another feature coming soon
which requires a user to block on a context until scheduling is
disabled. In that case we return the fence to the user and the user can
wait on that fence.

v2:
 (Daniele)
  - A comment about locking the blocked incr / decr
  - A comments about the use of the fence
  - Update commit message explaining why fence
  - Delete redundant check blocked count in unblock function
  - Ring buffer implementation
  - Comment about blocked in submission path
  - Shorter rpm path
v3:
 (Checkpatch)
  - Fix typos in commit message
 (Daniel)
  - Rework to simplier locking structure in guc_context_block / unblock
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-26-matthew.brost@intel.com

When using GuC submission, if a context gets banned disable scheduling
and mark all inflight requests as complete.

Cc: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-25-matthew.brost@intel.com

Use the official driver default scheduling policies for configuring
the GuC scheduler rather than a bunch of hardcoded values.

v2:
 (Matthew Brost)
  - Move I915_ENGINE_WANT_FORCED_PREEMPTION to later patch
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Cc: Jose Souza <jose.souza@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-21-matthew.brost@intel.com

In the case of a full GPU reset (e.g. because GuC has died or because
GuC's hang detection has been disabled), the driver can't rely on GuC
reporting the guilty context. Instead, the driver needs to scan all
active contexts and find one that is currently executing, as per the
execlist mode behaviour. In GuC mode, this scan is different to
execlist mode as the active request list is handled very differently.

Similarly, the request state dump in debugfs needs to be handled
differently when in GuC submission mode.

Also refactured some of the request scanning code to avoid duplication
across the multiple code paths that are now replicating it.
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-20-matthew.brost@intel.com

We receive notification of an engine reset from GuC at its
completion. Meaning GuC has potentially cleared any HW state
we may have been interested in capturing. GuC resumes scheduling
on the engine post-reset, as the resets are meant to be transparent,
further muddling our error state.

There is ongoing work to define an API for a GuC debug state dump. The
suggestion for now is to manually disable FW initiated resets in cases
where debug state is needed.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-19-matthew.brost@intel.com

GuC will notify the driver, via G2H, if it fails to
reset an engine. We recover by resorting to a full GPU
reset.

v2:
 (John Harrison):
  - s/drm_dbg/drm_err
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NFernando Pacheco <fernando.pacheco@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-14-matthew.brost@intel.com

GuC will issue a reset on detecting an engine hang and will notify
the driver via a G2H message. The driver will service the notification
by resetting the guilty context to a simple state or banning it
completely.

v2:
 (John Harrison)
  - Move msg[0] lookup after length check
v3:
 (John Harrison)
  - s/drm_dbg/drm_err

Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-13-matthew.brost@intel.com

The new GuC interface introduces an MMIO H2G command,
INTEL_GUC_ACTION_RESET_CLIENT, which is used to implement suspend. This
MMIO tears down any active contexts generating a context reset G2H CTB
for each. Once that step completes the GuC tears down the CTB
channels. It is safe to suspend once this MMIO H2G command completes
and all G2H CTBs have been processed. In practice the i915 will likely
never receive a G2H as suspend should only be called after the GPU is
idle.

Resume is implemented in the same manner as before - simply reload the
GuC firmware and reinitialize everything (e.g. CTB channels, contexts,
etc..).

v2:
 (Michel / John H)
  - INTEL_GUC_ACTION_RESET_CLIENT 0x5B01 -> 0x5507

Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-12-matthew.brost@intel.com

If submission is disabled by the backend for any reason, reset the GPU
immediately in the heartbeat code as the backend can't be reenabled
until the GPU is reset.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-10-matthew.brost@intel.com

Reset implementation for new GuC interface. This is the legacy reset
implementation which is called when the i915 owns the engine hang check.
Future patches will offload the engine hang check to GuC but we will
continue to maintain this legacy path as a fallback and this code path
is also required if the GuC dies.

With the new GuC interface it is not possible to reset individual
engines - it is only possible to reset the GPU entirely. This patch
forces an entire chip reset if any engine hangs.

v2:
 (Michal)
  - Check for -EPIPE rather than -EIO (CT deadlock/corrupt check)
v3:
 (John H)
  - Split into a series of smaller patches
v4:
 (John H)
  - Fix typo
  - Add braces around if statements in reset code
v5:
 (Checkpatch)
  - Fix warnings

Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <john.c.harrison@intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-9-matthew.brost@intel.com

Move active request tracking to a backend vfunc rather than assuming all
backends want to do this in the manner. In the of case execlists /
ring submission the tracking is on the physical engine while with GuC
submission it is on the context.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-8-matthew.brost@intel.com

With GuC virtual engines the physical engine which a request executes
and completes on isn't known to the i915. Therefore we can't attach a
request to a physical engines breadcrumbs. To work around this we create
a single breadcrumbs per engine class when using GuC submission and
direct all physical engine interrupts to this breadcrumbs.

v2:
 (John H)
  - Rework header file structure so intel_engine_mask_t can be in
    intel_engine_types.h
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
CC: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-6-matthew.brost@intel.com