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

The serial number tracking of engines happens at the backend of
request submission and was expecting to only be given physical
engines. However, in GuC submission mode, the decomposition of virtual
to physical engines does not happen in i915. Instead, requests are
submitted to their virtual engine mask all the way through to the
hardware (i.e. to GuC). This would mean that the heart beat code
thinks the physical engines are idle due to the serial number not
incrementing. Which in turns means hangcheck does not work for
GuC virtual engines.

This patch updates the tracking to decompose virtual engines into
their physical constituents and tracks the request against each. This
is not entirely accurate as the GuC will only be issuing the request
to one physical engine. However, it is the best that i915 can do given
that it has no knowledge of the GuC's scheduling decisions.

Downside of this is that all physical engines constituting a GuC
virtual engine will be periodically unparked (even during just a single
context executing) in order to be pinged with a heartbeat request.
However the power and performance cost of this is not expected to be
measurable (due low frequency of heartbeat pulses) and it is considered
an easier option than trying to make changes to GuC firmware.

v2:
 (Tvrtko)
  - Update commit message
  - Have default behavior if no vfunc present
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/20210727002348.97202-3-matthew.brost@intel.com

Implement GuC virtual engines. Rather simple implementation, basically
just allocate an engine, setup context enter / exit function to virtual
engine specific functions, set all other variables / functions to guc
versions, and set the engine mask to that of all the siblings.

v2: Update to work with proto-ctx
v3:
 (Daniele)
  - Drop include, add comment to intel_virtual_engine_has_heartbeat

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
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/20210727002348.97202-2-matthew.brost@intel.com

Add intel_context tracing. These trace points are particular helpful
when debugging the GuC firmware and can be enabled via
CONFIG_DRM_I915_LOW_LEVEL_TRACEPOINTS kernel config option.

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/20210721215101.139794-19-matthew.brost@intel.com

Add trace point for GuC submit. Extended existing request trace points
to include submit fence value,, guc_id, and ring tail value.

v2: Fix white space alignment in i915_request_add trace point
v3: Delete dep_from , dep_to (Tvrtko)

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/20210721215101.139794-18-matthew.brost@intel.com

Update GuC debugfs to support the new GuC structures.

v2:
 (John Harrison)
  - Remove intel_lrc_reg.h include from i915_debugfs.c
 (Michal)
  - Rename GuC debugfs functions
Signed-off-by: NJohn 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/20210721215101.139794-17-matthew.brost@intel.com

When running the GuC the GPU can't be considered idle if the GuC still
has contexts pinned. As such, a call has been added in
intel_gt_wait_for_idle to idle the UC and in turn the GuC by waiting for
the number of unpinned contexts to go to zero.

v2: rtimeout -> remaining_timeout
v3: Drop unnecessary includes, guc_submission_busy_loop ->
guc_submission_send_busy_loop, drop negatie timeout trick, move a
refactor of guc_context_unpin to earlier path (John H)
v4: Add stddef.h back into intel_gt_requests.h, sort circuit idle
function if not in GuC submission mode

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/20210721215101.139794-16-matthew.brost@intel.com

Ensure G2H response has space in the buffer before sending H2G CTB as
the GuC can't handle any backpressure on the G2H interface.

v2:
 (Matthew)
  - s/INTEL_GUC_SEND/INTEL_GUC_CT_SEND
v3:
 (Matthew)
  - Add G2H credit accounting to blocking path, add g2h_release_space
    helper
 (John H)
  - CTB_G2H_BUFFER_SIZE / 4 == G2H_ROOM_BUFFER_SIZE
Signed-off-by: NJohn 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/20210721215101.139794-15-matthew.brost@intel.com

Extend the deregistration context fence to fence whne a GuC context has
scheduling disable pending.

v2:
 (John H)
  - Update comment why we check the pin count within spin lock

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/20210721215101.139794-11-matthew.brost@intel.com

With GuC scheduling, it isn't safe to unpin a context while scheduling
is enabled for that context as the GuC may touch some of the pinned
state (e.g. LRC). To ensure scheduling isn't enabled when an unpin is
done, a call back is added to intel_context_unpin when pin count == 1
to disable scheduling for that context. When the response CTB is
received it is safe to do the final unpin.

Future patches may add a heuristic / delay to schedule the disable
call back to avoid thrashing on schedule enable / disable.

v2:
 (John H)
  - s/drm_dbg/drm_err
 (Daneiel)
  - Clean up sched state function

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/20210721215101.139794-9-matthew.brost@intel.com

Sometimes during context pinning a context with the same guc_id is
registered with the GuC. In this a case deregister must be done before
the context can be registered. A fence is inserted on all requests while
the deregister is in flight. Once the G2H is received indicating the
deregistration is complete the context is registered and the fence is
released.

v2:
 (John H)
  - Fix commit message

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/20210721215101.139794-8-matthew.brost@intel.com

Implement GuC context operations which includes GuC specific operations
alloc, pin, unpin, and destroy.

v2:
 (Daniel Vetter)
  - Use msleep_interruptible rather than cond_resched in busy loop
 (Michal)
  - Remove C++ style comment
v3:
 (Matthew Brost)
  - Drop GUC_ID_START
 (John Harrison)
  - Fix a bunch of typos
  - Use drm_err rather than drm_dbg for G2H errors
 (Daniele)
  - Fix ;; typo
  - Clean up sched state functions
  - Add lockdep for guc_id functions
  - Don't call __release_guc_id when guc_id is invalid
  - Use MISSING_CASE
  - Add comment in guc_context_pin
  - Use shorter path to rpm
 (Daniele / CI)
  - Don't call release_guc_id on an invalid guc_id in destroy
v4:
 (Daniel Vetter)
  - Add FIXME comment
Signed-off-by: NJohn 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/20210721215101.139794-7-matthew.brost@intel.com

Add bypass tasklet submission path to GuC. The tasklet is only used if H2G
channel has backpresure.
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/20210721215101.139794-6-matthew.brost@intel.com

Implement GuC submission tasklet for new interface. The new GuC
interface uses H2G to submit contexts to the GuC. Since H2G use a single
channel, a single tasklet is used for the submission path.

Also the per engine interrupt handler has been updated to disable the
rescheduling of the physical engine tasklet, when using GuC scheduling,
as the physical engine tasklet is no longer used.

In this patch the field, guc_id, has been added to intel_context and is
not assigned. Patches later in the series will assign this value.

v2:
 (John Harrison)
  - Clean up some comments
v3:
 (John Harrison)
  - More comment cleanups

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/20210721215101.139794-5-matthew.brost@intel.com

Add LRC descriptor context lookup array which can resolve the
intel_context from the LRC descriptor index. In addition to lookup, it
can determine if the LRC descriptor context is currently registered with
the GuC by checking if an entry for a descriptor index is present.
Future patches in the series will make use of this array.

v2:
 (Michal)
  - "linux/xarray.h" -> <linux/xarray.h>
  - s/lrc/LRC
 (John H)
  - Fix commit message

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/20210721215101.139794-4-matthew.brost@intel.com

Remove old GuC stage descriptor, add LRC descriptor which will be used
by the new GuC interface implemented in this patch series.

v2:
 (John Harrison)
  - s/lrc/LRC/g

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/20210721215101.139794-3-matthew.brost@intel.com

The submission tasklet operates on i915_sched_engine, thus it is the
correct place for it.

v3:
 (Jason Ekstrand)
  Change sched_engine->engine to a void* private data pointer
  Add kernel doc
v4:
 (Daniele)
  Update private_data comment
  Set queue_priority_hint in kick_execlists
v5:
 (CI)
  Rebase and fix build error
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-9-matthew.brost@intel.com

Rather passing around an intel_engine_cs in the scheduling code, pass
around a i915_sched_engine.

v3:
 (Jason Ekstrand)
  Add READ_ONCE around rq->engine in lock_sched_engine
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJason Ekstrand <jason@jlekstrand.net>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-8-matthew.brost@intel.com

The schedule function should be in the schedule object.

v3:
 (Jason Ekstrand)
  Add kernel doc
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-6-matthew.brost@intel.com

Move active request tracking and its lock to i915_sched_engine. This
lock is also the submission lock so having it in the i915_sched_engine
is the correct place.

v3:
 (Jason Ekstrand)
  Add kernel doc
v6:
  Rebase
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.comk>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-5-matthew.brost@intel.com

Rather than touching schedule state in the generic PM code, reset the
priolist allocation when empty in the submission code. Add a wrapper
function to do this and update the backends to call it in the correct
place.

v3:
 (Jason Ekstrand)
  Update patch commit message with a better description
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJason Ekstrand <jason@jlekstrand.net>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-4-matthew.brost@intel.com

Add wrapper function around RB tree to determine if i915_sched_engine is
empty.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NJason Ekstrand <jason@jlekstrand.net>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-3-matthew.brost@intel.com

Introduce i915_sched_engine object which is lower level data structure
that i915_scheduler / generic code can operate on without touching
execlist specific structures. This allows additional submission backends
to be added without breaking the layering. Currently the execlists
backend uses 1 of these object per each engine (physical or virtual) but
future backends like the GuC will point to less instances utilizing the
reference counting.

This is a bit of detour to integrating the i915 with the DRM scheduler
but this object will still exist when the DRM scheduler lands in the
i915. It will however look a bit different. It will encapsulate the
drm_gpu_scheduler object plus and common variables (to the backends)
related to scheduling. Regardless this is a step in the right direction.

This patch starts the aforementioned transition by moving the priolist
into the i915_sched_engine object.

v3:
 (Jason Ekstrand)
  Update comment next to intel_engine_cs.virtual
  Add kernel doc
 (Checkpatch)
  Fix double the in commit message
v4:
 (Daniele)
  Update comment message.
  Add comment about subclass field
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210618010638.98941-2-matthew.brost@intel.com

This was done by the following semantic patch:

	@@ expression i915; @@
	- INTEL_GEN(i915)
	+ GRAPHICS_VER(i915)

	@@ expression i915; expression E; @@
	- INTEL_GEN(i915) >= E
	+ GRAPHICS_VER(i915) >= E

	@@ expression dev_priv; expression E; @@
	- !IS_GEN(dev_priv, E)
	+ GRAPHICS_VER(dev_priv) != E

	@@ expression dev_priv; expression E; @@
	- IS_GEN(dev_priv, E)
	+ GRAPHICS_VER(dev_priv) == E

	@@
	expression dev_priv;
	expression from, until;
	@@
	- IS_GEN_RANGE(dev_priv, from, until)
	+ IS_GRAPHICS_VER(dev_priv, from, until)

	@def@
	expression E;
	identifier id =~ "^gen$";
	@@
	- id = GRAPHICS_VER(E)
	+ ver = GRAPHICS_VER(E)

	@@
	identifier def.id;
	@@
	- id
	+ ver

It also takes care of renaming the variable we assign to GRAPHICS_VER()
so to use "ver" rather than "gen".
Signed-off-by: NLucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210605155356.4183026-2-lucas.demarchi@intel.com

In GuC submission mode the CS is owned by the GuC FW, so all CS status
interrupts are handled by it. We only need the user interrupt as that
signals request completion.

Since we're now starting the engines directly in GuC submission mode
when selected, we can stop switching back and forth between the
execlists and the GuC programming and select directly the correct
interrupt mask.
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>
Cc: John Harrison <john.c.harrison@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603051630.2635-4-matthew.brost@intel.com

The different submission backends each have their own preferred
behaviour and interrupt setup. Let each handle their own interrupts.

This becomes more useful later as we to extract the use of auxiliary
state in the interrupt handler that is backend specific.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210521183215.65451-4-matthew.brost@intel.com

Since we setup the submission method for the engines once, it is easy to
assign an enum and use that instead of probing into the backends.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210521183215.65451-3-matthew.brost@intel.com

Now that we no longer switch back and forth between guc and execlists,
we no longer need to restore the backend's vfunc and can leave them set
after initialisation. The only catch is that we lose the submission on
wedging and still need to reset the submit_request vfunc on unwedging.
Signed-off-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NMatthew Brost <matthew.brost@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210521183215.65451-2-matthew.brost@intel.com

This converts the driver to use the new tasklet API introduced in
commit 12cc923f ("tasklet: Introduce new initialization API")

v2: Fix up selftests/execlists.
Signed-off-by: NEmil Renner Berthing <kernel@esmil.dk>
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/20210126150155.1617-1-kernel@esmil.dkSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since we are not using any internal priority levels, and in the next few
patches will introduce a new index for which the optimisation is not so
lear cut, discard the small table within the priolist.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210120121439.17600-1-chris@chris-wilson.co.ukSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Initialize all required entries from guc_set_default_submission, instead
of calling the execlists function. The previously inherited setup has
been copied over from the execlist code and simplified by removing the
execlists submission-specific parts.

v2: move setting of relative_mmio flag to engine_setup_common (Chris)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <john.c.harrison@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> #v1
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210113021236.8164-5-daniele.ceraolospurio@intel.com

Instead of starting the engine in execlists submission mode and then
switching to GuC, start directly in GuC submission mode. The initial
setup functions have been copied over from the execlists code
and simplified by removing the execlists submission-specific parts.

v2: remove unneeded unexpected starting state check (Chris)
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <john.c.harrison@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/20210113021236.8164-4-daniele.ceraolospurio@intel.com

Delete GuC code unused in future patches that rewrite the GuC interface
to work with the new firmware. Most of the code deleted relates to
workqueues or execlist port. The code is safe to remove because we still
don't allow GuC submission to be enabled, even when overriding the
modparam, so it currently can't be reached.

The defines + structs for the process descriptor and workqueue remain.
Although the new GuC interface does not require either of these for the
normal submission path multi-lrc submission does. The usage of the
process descriptor and workqueue for multi-lrc will be quite different
from the code that is deleted in this patch. A future patch will
implement multi-lrc submission.

v2: add a code in the commit message about the code being safe to
remove (Chris)
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: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210113021236.8164-2-daniele.ceraolospurio@intel.com

Split the definition, construction and updating of the Logical Ring
Context from the execlist submission interface. The LRC is used by the
HW, irrespective of our different submission backends.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201219020343.22681-1-chris@chris-wilson.co.uk

We want to separate the utility functions for controlling the logical
ring context from the execlists submission mechanism (which is an
overgrown scheduler).

This is similar to Daniele's work to split up the files, but being
selfish I wanted to base it after my own changes to intel_lrc.c petered
out.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201209233618.4287-2-chris@chris-wilson.co.uk

Start using device specific parameters instead of module parameters for
most things. The module parameters become the immutable initial values
for i915 parameters. The device specific parameters in i915->params
start life as a copy of i915_modparams. Any later changes are only
reflected in the debugfs.

The stragglers are:

* i915.force_probe and i915.modeset. Needed before dev_priv is
  available. This is fine because the parameters are read-only and never
  modified.

* i915.verbose_state_checks. Passing dev_priv to I915_STATE_WARN and
  I915_STATE_WARN_ON would result in massive and ugly churn. This is
  handled by not exposing the parameter via debugfs, and leaving the
  parameter writable in sysfs. This may be fixed up in follow-up work.

* i915.inject_probe_failure. Only makes sense in terms of the module,
  not the device. This is handled by not exposing the parameter via
  debugfs.

v2: Fix uc i915 lookup code (Michał Winiarski)

Cc: Juha-Pekka Heikkilä <juha-pekka.heikkila@intel.com>
Cc: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: NMichał Winiarski <michal.winiarski@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200618150402.14022-1-jani.nikula@intel.com

Upon waiting a request (when asked), we gave that request a small
priority boost, not enough for it to cause preemption, but enough for it
to be scheduled next before all equals. We also used that bit to give
new clients a small priority boost, similar to FQ_CODEL, such that we
favoured short interactive tasks ahead of long running streams.

However, this is causing lots of complications with timeslicing where we
both want to honour the boost and yet ignore it. Those complications
cause unexpected user behaviour (tasks not being timesliced and run
concurrently as epxected), and the easiest way to resolve that is to
remove the boost. Hopefully, we can find a compromise again if we need
to, but in theory timeslicing itself and future more advanced schedulers
should give us the interactivity boost we seek.

Testcase: igt/gem_exec_schedule/lateslice
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507152338.7452-3-chris@chris-wilson.co.uk

The bspec is confusing on the nature of the upper 32bits of the LRC
descriptor. Once upon a time, it said that it uses the upper 32b to
decide if it should perform a lite-restore, and so we must ensure that
each unique context submitted to HW is given a unique CCID [for the
duration of it being on the HW]. Currently, this is achieved by using
a small circular tag, and assigning every context submitted to HW a
new id. However, this tag is being cleared on repinning an inflight
context such that we end up re-using the 0 tag for multiple contexts.

To avoid accidentally clearing the CCID in the upper 32bits of the LRC
descriptor, split the descriptor into two dwords so we can update the
GGTT address separately from the CCID.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1796
Fixes: 2935ed53 ("drm/i915: Remove logical HW ID")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428184751.11257-1-chris@chris-wilson.co.uk
(cherry picked from commit 2632f174)
(cherry picked from commit a4b70fcc587860f4b972f68217d8ebebe295ec15)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>

The bspec is confusing on the nature of the upper 32bits of the LRC
descriptor. Once upon a time, it said that it uses the upper 32b to
decide if it should perform a lite-restore, and so we must ensure that
each unique context submitted to HW is given a unique CCID [for the
duration of it being on the HW]. Currently, this is achieved by using
a small circular tag, and assigning every context submitted to HW a
new id. However, this tag is being cleared on repinning an inflight
context such that we end up re-using the 0 tag for multiple contexts.

To avoid accidentally clearing the CCID in the upper 32bits of the LRC
descriptor, split the descriptor into two dwords so we can update the
GGTT address separately from the CCID.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1796
Fixes: 2935ed53 ("drm/i915: Remove logical HW ID")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428184751.11257-1-chris@chris-wilson.co.uk

Trying to use i915_request_skip() prior to i915_request_add() causes us
to try and fill the ring upto request->postfix, which has not yet been
set, and so may cause us to memset() past the end of the ring.

Instead of skipping the request immediately, just flag the error on the
request (only accepting the first fatal error we see) and then clear the
request upon submission.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200304121849.2448028-1-chris@chris-wilson.co.uk