nouveau: offload fence uevents work to workqueue

This should break the deadlock between the fctx lock and the irq lock.

This offloads the processing off the work from the irq into a workqueue.

Cc: linux-stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/576237/

Revert "nouveau: push event block/allowing out of the fence context"

This reverts commit eacabb5462717a52fccbbbba458365a4f5e61f35.

This commit causes some regressions in desktop usage, this will
reintroduce the original deadlock in DRI_PRIME situations, I've
got an idea to fix it by offloading to a workqueue in a different
spot, however this code has a race condition where we sometimes
miss interrupts so I'd like to fix that as well.

Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

nouveau: push event block/allowing out of the fence context

There is a deadlock between the irq and fctx locks,
the irq handling takes irq then fctx lock
the fence signalling takes fctx then irq lock

This splits the fence signalling path so the code that hits
the irq lock is done in a separate work queue.

This seems to fix crashes/hangs when using nouveau gsp with
i915 primary GPU.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231222043308.3090089-11-airlied@gmail.com

drm/nouveau: fence: fix undefined fence state after emit

nouveau_fence_emit() can fail before and after initializing the
dma-fence and hence before and after initializing the dma-fence' kref.

In order to avoid nouveau_fence_emit() potentially failing before
dma-fence initialization pass the channel to nouveau_fence_new() already
and perform the required check before even allocating the fence.

While at it, restore the original behavior of nouveau_fence_new() and
add nouveau_fence_create() for separate (pre-)allocation instead. Always
splitting up allocation end emit wasn't a good idea in the first place.
Hence, limit it to the places where we actually need to pre-allocate.

Fixes: 7f2a0b50b2b2 ("drm/nouveau: fence: separate fence alloc and emit")
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829223847.4406-1-dakr@redhat.com

drm/nouveau: fence: fail to emit when fence context is killed

The new VM_BIND UAPI implementation introduced in subsequent commits
will allow asynchronous jobs processing push buffers and emitting
fences.

If a fence context is killed, e.g. due to a channel fault, jobs which
are already queued for execution might still emit new fences. In such a
case a job would hang forever.

To fix that, fail to emit a new fence on a killed fence context with
-ENODEV to unblock the job.

Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230804182406.5222-9-dakr@redhat.com

drm/nouveau: fence: separate fence alloc and emit

The new (VM_BIND) UAPI exports DMA fences through DRM syncobjs. Hence,
in order to emit fences within DMA fence signalling critical sections
(e.g. as typically done in the DRM GPU schedulers run_job() callback) we
need to separate fence allocation and fence emitting.

Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230804182406.5222-8-dakr@redhat.com

drm/nouveau/fifo: expose non-stall intr in host channel event class

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drm/nouveau: signal pending fences when channel has been killed

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: fix bogus GPL-2 license header

The bulk SPDX addition made all these files into GPL-2.0 licensed files.
However the remainder of the project is MIT-licensed, these files
(primarily header files) were simply missing the boiler plate and got
caught up in the global update.

Fixes: b24413180f5 (License cleanup: add SPDX GPL-2.0 license identifier to files with no license)
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Acked-by: Emil Velikov <emil.l.velikov@gmail.com>
Acked-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/kms/nv04-nv4x: move a bunch of pre-nv50 page flip code to dispnv04

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fifo: support channel count query

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/nouveau: remove unused nouveau_fence_work()

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: separate constant-va tracking from nvkm vma structure

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: remove unused sysmem fence code

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence/g84-: protect against concurrent access to semaphore buffers

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/kms/nv50: remove code to support non-atomic page flips

Made completely unreachable (and broken) by atomic commits.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

dma-buf: Rename struct fence to dma_fence

I plan to usurp the short name of struct fence for a core kernel struct,
and so I need to rename the specialised fence/timeline for DMA
operations to make room.

A consensus was reached in
https://lists.freedesktop.org/archives/dri-devel/2016-July/113083.html
that making clear this fence applies to DMA operations was a good thing.
Since then the patch has grown a bit as usage increases, so hopefully it
remains a good thing!

(v2...: rebase, rerun spatch)
v3: Compile on msm, spotted a manual fixup that I broke.
v4: Try again for msm, sorry Daniel

coccinelle script:
@@

@@
- struct fence
+ struct dma_fence
@@

@@
- struct fence_ops
+ struct dma_fence_ops
@@

@@
- struct fence_cb
+ struct dma_fence_cb
@@

@@
- struct fence_array
+ struct dma_fence_array
@@

@@
- enum fence_flag_bits
+ enum dma_fence_flag_bits
@@

@@
(
- fence_init
+ dma_fence_init
|
- fence_release
+ dma_fence_release
|
- fence_free
+ dma_fence_free
|
- fence_get
+ dma_fence_get
|
- fence_get_rcu
+ dma_fence_get_rcu
|
- fence_put
+ dma_fence_put
|
- fence_signal
+ dma_fence_signal
|
- fence_signal_locked
+ dma_fence_signal_locked
|
- fence_default_wait
+ dma_fence_default_wait
|
- fence_add_callback
+ dma_fence_add_callback
|
- fence_remove_callback
+ dma_fence_remove_callback
|
- fence_enable_sw_signaling
+ dma_fence_enable_sw_signaling
|
- fence_is_signaled_locked
+ dma_fence_is_signaled_locked
|
- fence_is_signaled
+ dma_fence_is_signaled
|
- fence_is_later
+ dma_fence_is_later
|
- fence_later
+ dma_fence_later
|
- fence_wait_timeout
+ dma_fence_wait_timeout
|
- fence_wait_any_timeout
+ dma_fence_wait_any_timeout
|
- fence_wait
+ dma_fence_wait
|
- fence_context_alloc
+ dma_fence_context_alloc
|
- fence_array_create
+ dma_fence_array_create
|
- to_fence_array
+ to_dma_fence_array
|
- fence_is_array
+ dma_fence_is_array
|
- trace_fence_emit
+ trace_dma_fence_emit
|
- FENCE_TRACE
+ DMA_FENCE_TRACE
|
- FENCE_WARN
+ DMA_FENCE_WARN
|
- FENCE_ERR
+ DMA_FENCE_ERR
)
(
...
)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161025120045.28839-1-chris@chris-wilson.co.uk

dma-buf/fence: make fence context 64 bit v2

Fence contexts are created on the fly (for example) by the GPU scheduler used
in the amdgpu driver as a result of an userspace request. Because of this
userspace could in theory force a wrap around of the 32bit context number
if it doesn't behave well.

Avoid this by increasing the context number to 64bits. This way even when
userspace manages to allocate a billion contexts per second it takes more
than 500 years for the context number to wrap around.

v2: fix printf formats as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1464786612-5010-2-git-send-email-deathsimple@vodafone.de

drm/nouveau/sw: turn flip completion into an event

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: finalise nvkm namespace switch (no binary change)

The namespace of NVKM is being changed to nvkm_ instead of nouveau_,
which will be used for the DRM part of the driver. This is being
done in order to make it very clear as to what part of the driver a
given symbol belongs to, and as a minor step towards splitting the
DRM driver out to be able to stand on its own (for virt).

Because there's already a large amount of churn here anyway, this is
as good a time as any to also switch to NVIDIA's device and chipset
naming to ease collaboration with them.

A comparison of objdump disassemblies proves no code changes.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: prevent stale fence->channel pointers, and protect with rcu

Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: assign fence_chan->name correctly

Make nouveau_fence_chan refcounted, to make trace_fence_destroy
always return the correct name without a race condition.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>

drm/nouveau: specify if interruptible wait is desired in nouveau_fence_sync

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>

drm/nouveau: use shared fences for readable objects

nouveau keeps track in userspace whether a buffer is being
written to or being read, but it doesn't use that information.

Change this to allow multiple readers on the same bo.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>

drm/ttm: flip the switch, and convert to dma_fence

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>

drm/nouveau: rework to new fence interface

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: delay busy bo vma removal until fence signals

As opposed to an explicit wait. Allows userspace to not stall waiting
on buffer deletion.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nv84-/fence: prepare for emit/sync support of sysram sequences

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence: make internal hooks part of the context

A step towards being able to provide fences from other engines not
connected to PFIFO.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nv17/fence: split from nv10 code

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nv84-/fence: abstract class emit/sync functions to virt+sequence

Now can be used to operate on any buffer mapped into the GPU virtual
address and not just the main inter-channel sync buffer.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nv84/fence: access fences with full virtual address, not offset

Allows most of the code to be shared between nv84/nvc0 implementations,
and paves the way for doing emit/sync on non-VRAM buffers (multi-gpu,
dma-buf).

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence/nv84-: put processes to sleep while waiting on fences

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nv17-50: restore fence buffer on resume

Since commit 5e120f6e4b3f35b741c5445dfc755f50128c3c44 "drm/nouveau/fence:
convert to exec engine, and improve channel sync" nouveau fence sync
implementation for nv17-50 and nvc0+ started to rely on state of fence buffer
left by previous sync operation. But as pinned bo's (where fence state is
stored) are not saved+restored across suspend/resume, we need to do it
manually.

nvc0+ was fixed by commit d6ba6d215a538a58f0f0026f0961b0b9125e8042
"drm/nvc0/fence: restore pre-suspend fence buffer context on resume".

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=50121

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

drm/nouveau: port all engines to new engine module format

This is a HUGE commit, but it's not nearly as bad as it looks - any problems
can be isolated to a particular chipset and engine combination. It was
simply too difficult to port each one at a time, the compat layers are
*already* ridiculous.

Most of the changes here are simply to the glue, the process for each of the
engine modules was to start with a standard skeleton and copy+paste the old
code into the appropriate places, fixing up variable names etc as needed.

v2: Marcin Slusarz <marcin.slusarz@gmail.com>
- fix find/replace bug in license header

v3: Ben Skeggs <bskeggs@redhat.com>
- bump indirect pushbuf size to 8KiB, 4KiB barely enough for userspace and
left no space for kernel's requirements during GEM pushbuf submission.
- fix duplicate assignments noticed by clang

v4: Marcin Slusarz <marcin.slusarz@gmail.com>
- add sparse annotations to nv04_fifo_pause/nv04_fifo_start
- use ioread32_native/iowrite32_native for fifo control registers

v5: Ben Skeggs <bskeggs@redhat.com>
- rebase on v3.6-rc4, modified to keep copy engine fix intact
- nv10/fence: unmap fence bo before destroying
- fixed fermi regression when using nvidia gr fuc
- fixed typo in supported dma_mask checking

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pageflip: kick flip handling out of engsw and into fence

This is all very much a policy thing, and hence will not belong in SW
after the rework.

engsw now only handles receiving the event to say "can flip now" and makes
a callback to perform the actual work.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence: un-port from nouveau_exec_engine interfaces

Still the same code, but not an "engine" anymore. The fence code is more of
a policy decision rather than exposing mechanisms, so it's not appropriate
to port it to the new engine subsystem.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence: fix a race where fence->channel can disappear

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence: convert to exec engine, and improve channel sync

Now have a somewhat simpler semaphore sync implementation for nv17:nv84,
and a switched to using semaphores as fences on nv84+ and making use of
the hardware's >= acquire operation.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/fence: minor api changes for an upcoming rework

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>