Upon unregistering the user interface, we mark the GPU as wedged to
ensure we push no new work to the GPU, and to flush all current work
from the GPU. Move this call to the GT backend.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200221235135.2883006-1-chris@chris-wilson.co.uk

We are quite trigger happy in cleaning up the firmware blobs, as we do
so from several error/fini paths in GuC/HuC/uC code. We do have the
__uc_cleanup_firmwares cleanup function, which unwinds
__uc_fetch_firmwares and is already called both from the error path of
gem_init and from gem_driver_release, so let's stop cleaning up from
all the other paths.

The fact that we're not cleaning the firmware immediately means that
we can't consider firmware availability as an indication of
initialization success. A "LOADABLE" status has been added to
indicate that the initialization was successful, to be used to
selectively load HuC only if HuC init has completed (HuC init failure
is not considered a fatal error).

v2: s/ready_to_load/loadable (Michal), only run guc/huc_fini if the
    fw is in loadable state
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com> #v1
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-9-daniele.ceraolospurio@intel.com

Now that we can differentiate wants vs uses GuC/HuC, intel_uc_init is
restricted to running only if we have successfully fetched the required
blob(s) and are committed to using the microcontroller(s).
The only remaining thing that can go wrong in uc_init is the allocation
of GuC/HuC related objects; if we get such a failure better to bail out
immediately instead of wedging later, like we do for e.g.
intel_engines_init, since without objects we can't use the HW, including
not being able to attempt the firmware load.

While at it, remove the unneeded fw_cleanup call (this is handled
outside of gt_init) and add a probe failure injection point for testing.
Also, update the logs for <g/h>uc_init failures to probe_failure() since
they will cause the driver load to fail.
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: NFernando Pacheco <fernando.pacheco@intel.com>
Reviewed-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-8-daniele.ceraolospurio@intel.com

To be able to differentiate the before and after of our commitment to
GuC submission, which will be used in follow-up patches to early set-up
the submission structures.

v2: move functions to guc_submission.h (Michal)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-7-daniele.ceraolospurio@intel.com

To be able to setup GuC submission functions during engine init we need
to commit to using GuC as soon as possible.
Currently, the only thing that can stop us from using the
microcontrollers once we've fetched the blobs is a fundamental
error (e.g. OOM); given that if we hit such an error we can't really
fall-back to anything, we can "officialize" the FW fetching completion
as the moment at which we're committing to using GuC.

To better differentiate this case, the uses_guc check, which indicates
that GuC is supported and was selected in modparam, is renamed to
wants_guc and a new uses_guc is introduced to represent the case were
we're committed to using the GuC. Note that uses_guc does still not imply
that the blob is actually loaded on the HW (is_running is the check for
that). Also, since we need to have attempted the fetch for the result
of uses_guc to be meaningful, we need to make sure we've moved away
from INTEL_UC_FIRMWARE_SELECTED.

All the GuC changes have been mirrored on the HuC for coherency.

v2: split fetch return changes and new macros to their own patches,
    support HuC only if GuC is wanted, improve "used" state
    description (Michal)

v3: s/wants_huc/uses_huc in uc_init_wopcm
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Fernando Pacheco <fernando.pacheco@intel.com> #v1
Reviewed-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-6-daniele.ceraolospurio@intel.com

We want to map uC-level checks to GuC/HuC-level ones. The mapping from
the uC state to the GuC/HuC one follows the same pattern for all the
functions:

 uc_xxx_guc() -> guc_is_yyy()

So we can easily use a macro to autogenerate the functions via macros by
passing in the 2 mapped states.

v2: Split this change to its own patch (Michal)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-5-daniele.ceraolospurio@intel.com

In a follow up patch we will rely on the fact that the status always
moves away from "SELECTED" after the fetch is attempted to decide what
to do with the GuC.

v2: Split this change to its own patch (Michal)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-4-daniele.ceraolospurio@intel.com

use intel_uc_uses_guc_submission() directly instead, to be consistent in
the way we check what we want to do with the GuC.

v2: do not go through ctx->vm->gt, use i915->gt instead
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com> #v1
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-3-daniele.ceraolospurio@intel.com

use intel_uc_uses_guc() directly instead, to be consistent in the way we
check what we want to do with the GuC.

v2: split guc_log_info changes to their own patch (Michal)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218223327.11058-2-daniele.ceraolospurio@intel.com

While we know that the waiters cannot disappear as we walk our list
(only that they might be added), the same cannot be said for our
signalers as they may be completed by the HW and retired as we process
this request. Ergo we need to use rcu to protect the list iteration and
remember to mark up the list_del_rcu.

v2: Mark the deps as safe-for-rcu

Fixes: 793c2261 ("drm/i915/gt: Protect execlists_hold/unhold from new waiters")
Fixes: 32ff621f ("drm/i915/gt: Allow temporary suspension of inflight requests")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200220075025.1539375-1-chris@chris-wilson.co.uk

For dgfx, we do not need to reconfigure the IA/ring frequencies of the
main processors as they are distinct devices.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219130119.1457693-1-chris@chris-wilson.co.uk

Currently, we check that a new context has a clear set of general
purpose registers. Add a little bit of hostility by preempting our new
context and re-poisoning the GPR to ensure that there is no context
leakage from preemption.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NRamalingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219123418.1447428-1-chris@chris-wilson.co.uk

Check that the CTX_TIMESTAMP is monotonic across context save/restore
and upon preemption.

References: https://gitlab.freedesktop.org/drm/intel/issues/1233Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NRamalingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219112004.1412791-1-chris@chris-wilson.co.uk

On dgfx, we only use l3cc and not mocs, but we share the table
containing both register definitions with Tigerlake. This confuses our
selftest that verifies that both sets of registers do contain the values
in our tables after various events (idling, reset, activity etc).

When constructing the table of register definitions, also include the
flags for which registers are valid so that information is computed
centrally and available to all callers.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Brian Welty <brian.welty@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218162150.1300405-10-chris@chris-wilson.co.uk

As we have the total runtime known to us, show it when dumping the
engine state for debug.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218162150.1300405-2-chris@chris-wilson.co.uk

Always flush the tasklet if we have pending submissions in
wait_for_submit(), so that even if we see the HW has started before we
process its ack, when we return the execlists state is well defined.

Fixes: 06289949 ("drm/i915/selftests: Check for any sign of request starting in wait_for_submit()")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218211215.1336341-1-chris@chris-wilson.co.uk

Just missed setting err along an interruptible error path for the
intel_engine_pulse().
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218162150.1300405-4-chris@chris-wilson.co.uk

We only want to wait until the request has been submitted at least once;
that is it is either in flight, or has been.

References: fcf7df7a ("drm/i915/selftests: Check for the error interrupt before we wait!")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218141305.1258394-1-chris@chris-wilson.co.uk

It's not clear whether this workaround is final yet, but the BSpec
indicates that userspace needs to set bit 9 of this register on demand:

   "To avoid sporadic corruptions “Set 0x7010[9] when Depth Buffer
   Surface Format is D16_UNORM , surface type is not NULL & 1X_MSAA"

Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2501Signed-off-by: NRafael Antognolli <rafael.antognolli@intel.com>
[mattrope: Tweaked comment while applying]
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200212191728.25227-1-rafael.antognolli@intel.com

The ringbuffer's vma is expected to be in the GGTT and that is now being
checked, so make sure the mocked ring declares it so.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200215205927.4170144-1-chris@chris-wilson.co.uk

Without selftests enabled, I915_SELFTEST_ONLY becomes a dummy,
generating a bare '0'. This causes the compiler to complain about a
useless line, and while we could use I915_SELFTEST_DECLARE instead, it
is a bit messier. Move the selftest-only code to a helper and make that
conditional on having selftests enabled.
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200217095835.599827-1-chris@chris-wilson.co.uk

GPU saves accumulated context runtime (in CS timestamp units) in PPHWSP
which will be useful for us in cases when we are not able to track context
busyness ourselves (like with GuC). Keep a copy of this in struct
intel_context from where it can be easily read even if the context is not
pinned.

v2:
 (Chris)
 * Do not store pphwsp address in intel_context.
 * Log CS wrap-around.
 * Simplify calculation by relying on integer wraparound.
v3:
 * Include total/avg in traces and error state for debugging
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200216133620.394962-1-chris@chris-wilson.co.uk

Sometimes the error interrupt can fire even before we have seen the
request go active -- in which case, we end up waiting until the timeout
as the request is already completed. Double check for this case!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200214120659.3888735-1-chris@chris-wilson.co.uk

Originally, I did not expect having to rewind a context upon
timeslicing: the point was to replace the executing context with a
non-executing one! However, given a second context that depends on
requests from the first, we may have to split the requests along the
first context to execute the second, causing us to partially replay the
first context and so have to rewind its RING_TAIL.

References: 5ba32c7b ("drm/i915/execlists: Always force a context reload when rewinding RING_TAIL")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200213140150.3639027-1-chris@chris-wilson.co.uk

With debugging turned off, we have to tell the compiler not to warn
about the unused debug locals.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200213081217.3107410-1-chris@chris-wilson.co.uk

This is in mcr range of register, thus we can only verify
it through mmio. Use engine wa list with mcr range verification
skip.

Fixes: 0db1a5f8 ("drm/i915: Implement Wa_1607090982")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200212165707.11143-1-mika.kuoppala@linux.intel.com

Show the ring/request/context state if we see what we believe is an
early CS completion.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211230944.1203098-1-chris@chris-wilson.co.uk

Apply vast quantities of poison and not tell anyone to see if we fall
for the trap of using a stale RING_HEAD.

References: 42827350 ("drm/i915/gt: Avoid resetting ring->head outside of its timeline mutex")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211205615.1190127-2-chris@chris-wilson.co.uk

Currently on execlists, we use a local hwsp for the kernel_context,
rather than the engine's HWSP, as this is the default for execlists.
However, seqno wrap requires allocating a new HWSP cacheline, and may
require pinning a new HWSP page in the GGTT. This operation requiring
pinning in the GGTT is not allowed within the kernel_context timeline,
as doing so may require re-entering the kernel_context in order to evict
from the GGTT. As we want to avoid requiring a new HWSP for the
kernel_context, we can use the permanently pinned engine's HWSP instead.
However to do so we must prevent the use of semaphores reading the
kernel_context's HWSP, as the use of semaphores do not support rollover
onto the same cacheline. Fortunately, the kernel_context is mostly
isolated, so unlikely to give benefit to semaphores.
Reported-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200210205722.794180-5-chris@chris-wilson.co.uk

We can not require that the system process a tasklet in reasonable time
(thanks be to ksoftirqd), but we can insist that having waited
sufficiently for the error interrupt to have been raised and having
kicked the tasklet, the reset has begun and the request will be marked
as in error (if not already completed).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200210205722.794180-3-chris@chris-wilson.co.uk

We manipulate ring->head while active in i915_request_retire underneath
the timeline manipulation. We cannot rely on a stable ring->head outside
of the timeline->mutex, in particular while setting up the context for
resume and reset.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/1126
Fixes: 08819549 ("drm/i915: Introduce intel_context.pin_mutex for pin management")
Fixes: e5dadff4 ("drm/i915: Protect request retirement with timeline->mutex")
References: f3c0efc9 ("drm/i915/execlists: Leave resetting ring to intel_ring")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211120131.958949-1-chris@chris-wilson.co.uk

live_preempt_hang's use of hang injection has been superseded by
live_preempt_reset's use of an non-preemptible spinner. The latter does
not require intrusive hacks into the code.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200209230838.361154-2-chris@chris-wilson.co.uk

On an allocation error path for live_hwsp_alternate, we dropped the
engine wakeref before we had even acquired it.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200209131922.180287-4-chris@chris-wilson.co.uk

Recording the frequent inspection of CSB head/tail when there is
expected to be no update adds noise to the debug trace. (Not entirely
useless, but since we know the sequence of function calls, we can
surmise the function was called -- so redundant.)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200209131922.180287-2-chris@chris-wilson.co.uk

In eliminating the recursion from walking the tree of signalers/waiters
for processing the hold/unhold operations, a crucial error crept in
where we looked at the parent request and not the list element when
processing the list.

Brown paper bag, much?

Closes: https://gitlab.freedesktop.org/drm/intel/issues/1166
Fixes: 32ff621f ("drm/i915/gt: Allow temporary suspension of inflight requests")
Fixes: 74831738 ("drm/i915/execlists: Offline error capture")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200209131922.180287-1-chris@chris-wilson.co.uk

We have switched from tail manipulation to forced context restore
to implement WaIdleLiteRestore. Remove the old defines and comments.

Note: we still do emit the WA tail, and use it as our first attempt to
avoid forcing a full-restore instead of a lite-restore, we just have a
much stronger backup mechanism for repeated preemptions.

References: f26a9e95 ("drm/i915/gt: Detect if we miss WaIdleLiteRestore")
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200203163312.15475-1-mika.kuoppala@linux.intel.com

If we rewind the RING_TAIL on a context, due to a preemption event, we
must force the context restore for the RING_TAIL update to be properly
handled. Rather than note which preemption events may cause us to rewind
the tail, compare the new request's tail with the previously submitted
RING_TAIL, as it turns out that timeslicing was causing unexpected
rewinds.

   <idle>-0       0d.s2 1280851190us : __execlists_submission_tasklet: 0000:00:02.0 rcs0: expired last=130:4698, prio=3, hint=3
   <idle>-0       0d.s2 1280851192us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 66:119966, current 119964
   <idle>-0       0d.s2 1280851195us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4698, current 4695
   <idle>-0       0d.s2 1280851198us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
^----  Note we unwind 2 requests from the same context

   <idle>-0       0d.s2 1280851208us : __i915_request_submit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
   <idle>-0       0d.s2 1280851213us : __i915_request_submit: 0000:00:02.0 rcs0: fence 134:1508, current 1506
^---- But to apply the new timeslice, we have to replay the first request
      before the new client can start -- the unexpected RING_TAIL rewind

   <idle>-0       0d.s2 1280851219us : trace_ports: 0000:00:02.0 rcs0: submit { 130:4696*, 134:1508 }
 synmark2-5425    2..s. 1280851239us : process_csb: 0000:00:02.0 rcs0: cs-irq head=5, tail=0
 synmark2-5425    2..s. 1280851240us : process_csb: 0000:00:02.0 rcs0: csb[0]: status=0x00008002:0x00000000
^---- Preemption event for the ELSP update; note the lite-restore

 synmark2-5425    2..s. 1280851243us : trace_ports: 0000:00:02.0 rcs0: preempted { 130:4698, 66:119966 }
 synmark2-5425    2..s. 1280851246us : trace_ports: 0000:00:02.0 rcs0: promote { 130:4696*, 134:1508 }
 synmark2-5425    2.... 1280851462us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4700, current 4695
 synmark2-5425    2.... 1280852111us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4702, current 4695
 synmark2-5425    2.Ns1 1280852296us : process_csb: 0000:00:02.0 rcs0: cs-irq head=0, tail=2
 synmark2-5425    2.Ns1 1280852297us : process_csb: 0000:00:02.0 rcs0: csb[1]: status=0x00000814:0x00000000
 synmark2-5425    2.Ns1 1280852299us : trace_ports: 0000:00:02.0 rcs0: completed { 130:4696!, 134:1508 }
 synmark2-5425    2.Ns1 1280852301us : process_csb: 0000:00:02.0 rcs0: csb[2]: status=0x00000818:0x00000040
 synmark2-5425    2.Ns1 1280852302us : trace_ports: 0000:00:02.0 rcs0: completed { 134:1508, 0:0 }
 synmark2-5425    2.Ns1 1280852313us : process_csb: process_csb:2336 GEM_BUG_ON(!i915_request_completed(*execlists->active) && !reset_in_progress(execlists))

Fixes: 8ee36e04 ("drm/i915/execlists: Minimalistic timeslicing")
Referenecs: 82c69bf5 ("drm/i915/gt: Detect if we miss WaIdleLiteRestore")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.4+
Link: https://patchwork.freedesktop.org/patch/msgid/20200207211452.2860634-1-chris@chris-wilson.co.uk

If a request is being re-run after an innocent reset, it is marked as
-EAGAIN. So only skip an engine reset if the request is marked as -EIO.

Testcase: igt/gem_ctx_exec/basic-nohangcheck
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200207161602.2838218-1-chris@chris-wilson.co.uk

SIMD16 with Src0 scalar might conflict between Src1/Src2 and cause
GRF read issue. Workaround this issue by setting bit 14 in 0xe4f4
which will disable early read/src swap of Src0.
Signed-off-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200207155138.30978-2-mika.kuoppala@linux.intel.com

Disable TEDOP clock gating flow by programming 0x20A0[19] = 1

References: HSDES#1407928979
Signed-off-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200207155138.30978-1-mika.kuoppala@linux.intel.com