Add the initial nova-drm driver skeleton.
nova-drm is connected to nova-core through the auxiliary bus and
implements the DRM parts of the nova driver stack.
For now, it implements the fundamental DRM abstractions, i.e. creates a
DRM device and registers it, exposing a three sample IOCTLs.
DRM_IOCTL_NOVA_GETPARAM
- provides the PCI bar size from the bar that maps the GPUs VRAM
from nova-core
DRM_IOCTL_NOVA_GEM_CREATE
- creates a new dummy DRM GEM object and returns a handle
DRM_IOCTL_NOVA_GEM_INFO
- provides metadata for the DRM GEM object behind a given handle
I implemented a small userspace test suite [1] that utilizes this
interface.
Link: https://gitlab.freedesktop.org/dakr/drm-test [1]
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Dave Airlie <airlied@redhat.com>
Link: https://lore.kernel.org/r/20250424160452.8070-3-dakr@kernel.org
[ Kconfig: depend on DRM=y rather than just DRM. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The doctest requires `CONFIG_PCI`:
error[E0432]: unresolved import `kernel::pci`
--> rust/doctests_kernel_generated.rs:2689:44
|
2689 | use kernel::{device::Core, devres::Devres, pci};
| ^^^ no `pci` in the root
|
note: found an item that was configured out
--> rust/kernel/lib.rs:96:9
note: the item is gated here
--> rust/kernel/lib.rs:95:1
Thus conditionally compile it (which still checks the syntax).
Fixes: f301cb978c ("rust: devres: implement Devres::access()")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250511182533.1016163-1-ojeda@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement a direct accessor for the data stored within the Devres for
cases where we can prove that we own a reference to a Device<Bound>
(i.e. a bound device) of the same device that was used to create the
corresponding Devres container.
Usually, when accessing the data stored within a Devres container, it is
not clear whether the data has been revoked already due to the device
being unbound and, hence, we have to try whether the access is possible
and subsequently keep holding the RCU read lock for the duration of the
access.
However, when we can prove that we hold a reference to Device<Bound>
matching the device the Devres container has been created with, we can
guarantee that the device is not unbound for the duration of the
lifetime of the Device<Bound> reference and, hence, it is not possible
for the data within the Devres container to be revoked.
Therefore, in this case, we can bypass the atomic check and the RCU read
lock, which is a great optimization and simplification for drivers.
Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Link: https://lore.kernel.org/r/20250428140137.468709-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
When `CONFIG_AUXILIARY_BUS` is disabled, `parent()` is still dead code:
error: method `parent` is never used
--> rust/kernel/device.rs:71:19
|
64 | impl<Ctx: DeviceContext> Device<Ctx> {
| ------------------------------------ method in this implementation
...
71 | pub(crate) fn parent(&self) -> Option<&Self> {
| ^^^^^^
|
= note: `-D dead-code` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(dead_code)]`
Thus reintroduce the `expect`, but now as a conditional one. Do so as
`dead_code` since that is narrower.
An `allow` would also be possible, but Danilo wants to catch new users
in the future [1].
Link: https://lore.kernel.org/rust-for-linux/aBE8qQrpXOfru_K3@pollux/ [1]
Fixes: ce735e73dd ("rust: auxiliary: add auxiliary device / driver abstractions")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250429210629.513521-1-ojeda@kernel.org
[ Adjust commit subject to "rust: device: conditionally expect
`dead_code` for `parent()`". - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
DRM GEM is the DRM memory management subsystem used by most modern
drivers; add a Rust abstraction for DRM GEM.
This includes the BaseObject trait, which contains operations shared by
all GEM object classes.
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-8-dakr@kernel.org
[ Rework of GEM object abstractions
* switch to the Opaque<T> type
* fix (mutable) references to struct drm_gem_object (which in this
context is UB)
* drop all custom reference types in favor of AlwaysRefCounted
* bunch of minor changes and simplifications (e.g. IntoGEMObject
trait)
* write and fix safety and invariant comments
* remove necessity for and convert 'as' casts
* original source archive: https://archive.is/dD5SL
- Danilo ]
[ Fix missing CONFIG_DRM guards in rust/helpers/drm.c. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
A DRM File is the DRM counterpart to a kernel file structure,
representing an open DRM file descriptor.
Add a Rust abstraction to allow drivers to implement their own File types
that implement the DriverFile trait.
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-7-dakr@kernel.org
[ Rework of drm::File
* switch to the Opaque<T> type
* fix (mutable) references to struct drm_file (which in this context
is UB)
* restructure and rename functions to align with common kernel
schemes
* write and fix safety and invariant comments
* remove necessity for and convert 'as' casts
* original source archive: https://archive.is/GH8oy
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement the DRM driver `Registration`.
The `Registration` structure is responsible to register and unregister a
DRM driver. It makes use of the `Devres` container in order to allow the
`Registration` to be owned by devres, such that it is automatically
dropped (and the DRM driver unregistered) once the parent device is
unbound.
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-6-dakr@kernel.org
[ Rework of drm::Registration
* move VTABLE to drm::Device to prevent use-after-free bugs; VTABLE
needs to be bound to the lifetime of drm::Device, not the
drm::Registration
* combine new() and register() to get rid of the registered boolean
* remove file_operations
* move struct drm_device creation to drm::Device
* introduce Devres
* original source archive: https://archive.is/Pl9ys
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement the DRM driver abstractions.
The `Driver` trait provides the interface to the actual driver to fill
in the driver specific data, such as the `DriverInfo`, driver features
and IOCTLs.
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-4-dakr@kernel.org
[ MISC changes
* remove unnecessary DRM features; make remaining ones crate private
* add #[expect(unused)] to avoid warnings
* add sealed trait
* remove shmem::Object references
* original source archive: https://archive.is/Pl9ys
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
DRM drivers need to be able to declare which driver-specific ioctls they
support. Add an abstraction implementing the required types and a helper
macro to generate the ioctl definition inside the DRM driver.
Note that this macro is not usable until further bits of the abstraction
are in place (but it will not fail to compile on its own, if not called).
Signed-off-by: Asahi Lina <lina@asahilina.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-3-dakr@kernel.org
[ MISC fixes
* wrap raw_data in Opaque to avoid UB when creating a reference
* fix IOCTL sample declaration
* fix safety comment of IOCTL argument
* original source archive: https://archive.is/LqHDQ
- Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
In the Rust DRM device abstraction we need to allocate a struct
drm_device.
Currently, there are two options, the deprecated drm_dev_alloc() (which
does not support subclassing) and devm_drm_dev_alloc(). The latter
supports subclassing, but also manages the initial reference through
devres for the parent device.
In Rust we want to conform with the subclassing pattern, but do not want
to get the initial reference managed for us, since Rust has its own,
idiomatic ways to properly deal with it.
There are two options to achieve this.
1) Allocate the memory ourselves with a KBox.
2) Implement __drm_dev_alloc(), which supports subclassing, but is
unmanged.
While (1) would be possible, it would be cumbersome, since it would
require exporting drm_dev_init() and drmm_add_final_kfree().
Hence, go with option (2) and implement __drm_dev_alloc().
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20250410235546.43736-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Revocable::try_access() returns a guard through which the wrapped object
can be accessed. Code that can sleep is not allowed while the guard is
held; thus, it is common for the caller to explicitly drop it before
running sleepable code, e.g:
let b = bar.try_access()?;
let reg = b.readl(...);
// Don't forget this or things could go wrong!
drop(b);
something_that_might_sleep();
let b = bar.try_access()?;
let reg2 = b.readl(...);
This is arguably error-prone. try_access_with() provides an arguably
safer alternative, by taking a closure that is run while the guard is
held, and by dropping the guard automatically after the closure
completes. This way, code can be organized more clearly around the
critical sections and the risk of forgetting to release the guard when
needed is considerably reduced:
let reg = bar.try_access_with(|b| b.readl(...))?;
something_that_might_sleep();
let reg2 = bar.try_access_with(|b| b.readl(...))?;
The closure can return nothing, or any value including a Result which is
then wrapped inside the Option returned by try_access_with. Error
management is driver-specific, so users are encouraged to create their
own macros that map and flatten the returned values to something
appropriate for the code they are working on.
Suggested-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250411-try_with-v4-1-f470ac79e2e2@nvidia.com
[ Link `None`, `Some`, `Option` in doc-comment. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Add a sample Rust auxiliary driver based on a PCI driver for QEMU's
"pci-testdev" device.
The PCI driver only registers an auxiliary device, in order to make the
corresponding auxiliary driver probe.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250414131934.28418-6-dakr@kernel.org
[ Use `ok_or()` when accessing auxiliary::Device::parent(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement the basic auxiliary abstractions required to implement a
driver matching an auxiliary device.
The design and implementation is analogous to PCI and platform and is
based on the generic device / driver abstractions.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-4-dakr@kernel.org
[ Fix typos, `let _ =` => `drop()`, use `kernel::ffi`. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement TryFrom<&device::Device> for &Device.
This allows us to get a &platform::Device from a generic &Device in a safe
way; the conversion fails if the device' bus type does not match with
the platform bus type.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250321214826.140946-4-dakr@kernel.org
[ Support device context types, use dev_is_platform() helper. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Implement TryFrom<&device::Device> for &Device.
This allows us to get a &pci::Device from a generic &Device in a safe
way; the conversion fails if the device' bus type does not match with
the PCI bus type.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250321214826.140946-3-dakr@kernel.org
[ Support device context types, use dev_is_pci() helper. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Introduce "Bound" device context
Introduce the "Bound" device context, such that it can be ensured to only
ever pass a bound device to APIs that require this precondition. [1]
This tag exists to share the patches from [1] between multiple trees.
[1] https://lore.kernel.org/lkml/20250413173758.12068-1-dakr@kernel.org/
The Bound device context indicates that a device is bound to a driver.
It must be used for APIs that require the device to be bound, such as
Devres or dma::CoherentAllocation.
Implement Bound and add the corresponding Deref hierarchy, as well as the
corresponding ARef conversion for this device context.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-7-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Pull soundwire fix from Vinod Koul:
- add missing config symbol CONFIG_SND_HDA_EXT_CORE required for asoc
driver CONFIG_SND_SOF_SOF_HDA_SDW_BPT
* tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire:
ASoC: SOF: Intel: Let SND_SOF_SOF_HDA_SDW_BPT select SND_HDA_EXT_CORE
Support up to 8192 processors
Add cpuidle governor debug telemetry, disabled by default
Update default output to exclude cpuidle invocation counts
Bug fixes
Signed-off-by: Len Brown <len.brown@intel.com>
Create "pct_idle" counter group, the sofware notion of residency
so it can now be singled out, independent of other counter groups.
Create "cpuidle" group, the cpuidle invocation counts.
Disable "cpuidle", by default.
Create "swidle" = "cpuidle" + "pct_idle".
Undocument "sysfs", the old name for "swidle", but keep it working
for backwards compatibilty.
Create "hwidle", all the HW idle counters
Modify "idle", enabled by default
"idle" = "hwidle" + "pct_idle" (and now excludes "cpuidle")
Signed-off-by: Len Brown <len.brown@intel.com>
Pull perf event fix from Ingo Molnar:
"Fix a perf events time accounting bug"
* tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix child_total_time_enabled accounting bug at task exit
Pull scheduler fixes from Ingo Molnar:
- Fix a nonsensical Kconfig combination
- Remove an unnecessary rseq-notification
* tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Eliminate useless task_work on execve
sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP
... and don't error out so hard on missing module descriptions.
Before commit 6c6c1fc09d ("modpost: require a MODULE_DESCRIPTION()")
we used to warn about missing module descriptions, but only when
building with extra warnigns (ie 'W=1').
After that commit the warning became an unconditional hard error.
And it turns out not all modules have been converted despite the claims
to the contrary. As reported by Damian Tometzki, the slub KUnit test
didn't have a module description, and apparently nobody ever really
noticed.
The reason nobody noticed seems to be that the slub KUnit tests get
disabled by SLUB_TINY, which also ends up disabling a lot of other code,
both in tests and in slub itself. And so anybody doing full build tests
didn't actually see this failre.
So let's disable SLUB_TINY for build-only tests, since it clearly ends
up limiting build coverage. Also turn the missing module descriptions
error back into a warning, but let's keep it around for non-'W=1'
builds.
Reported-by: Damian Tometzki <damian@riscv-rocks.de>
Link: https://lore.kernel.org/all/01070196099fd059-e8463438-7b1b-4ec8-816d-173874be9966-000000@eu-central-1.amazonses.com/
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Fixes: 6c6c1fc09d ("modpost: require a MODULE_DESCRIPTION()")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Probe cpuidle "sysfs" residency and counts separately,
since soon we will make one disabled on, and the
other disabled off.
Clarify that some BIC (build-in-counters) are actually "groups".
since we're about to re-name some of those groups.
no functional change.
Signed-off-by: Len Brown <len.brown@intel.com>
Do fflush() to discard the buffered data, before each read of the
graphics sysfs knobs.
Fixes: ba99a4fc8c ("tools/power turbostat: Remove unnecessary fflush() call")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Document that on Intel Granite Rapids Systems,
Uncore domains 0-2 are CPU domains, and
uncore domains 3-4 are IO domains.
Signed-off-by: Len Brown <len.brown@intel.com>
The CoreThr column displays total thermal throttling events
since boot time.
Change it to report events during the measurement interval.
This is more useful for showing a user the current conditions.
Total events since boot time are still available to the user via
/sys/devices/system/cpu/cpu*/thermal_throttle/*
Document CoreThr on turbostat.8
Fixes: eae97e053f ("turbostat: Support thermal throttle count print")
Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Chen Yu <yu.c.chen@intel.com>
On systems with >= 1024 cpus (in my case 1152), turbostat fails with the error output:
"turbostat: /sys/fs/cgroup/cpuset.cpus.effective: cpu str malformat 0-1151"
A similar error appears with the use of turbostat --cpu when the inputted cpu
range contains a cpu number >= 1024:
# turbostat -c 1100-1151
"--cpu 1100-1151" malformed
...
Both errors are caused by parse_cpu_str() reaching its limit of CPU_SUBSET_MAXCPUS.
It's a good idea to limit the maximum cpu number being parsed, but 1024 is too low.
For a small increase in compute and allocated memory, increasing CPU_SUBSET_MAXCPUS
brings support for parsing cpu numbers >= 1024.
Increase CPU_SUBSET_MAXCPUS to 8192, a common setting for CONFIG_NR_CPUS on x86_64.
Signed-off-by: Justin Ernst <justin.ernst@hpe.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Pull timer cleanups from Thomas Gleixner:
"A set of final cleanups for the timer subsystem:
- Convert all del_timer[_sync]() instances over to the new
timer_delete[_sync]() API and remove the legacy wrappers.
Conversion was done with coccinelle plus some manual fixups as
coccinelle chokes on scoped_guard().
- The final cleanup of the hrtimer_init() to hrtimer_setup()
conversion.
This has been delayed to the end of the merge window, so that all
patches which have been merged through other trees are in mainline
and all new users are catched.
Doing this right before rc1 ensures that new code which is merged post
rc1 is not introducing new instances of the original functionality"
* tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing/timers: Rename the hrtimer_init event to hrtimer_setup
hrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()
hrtimers: Rename debug_init() to debug_setup()
hrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()
hrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()
hrtimers: Make callback function pointer private
hrtimers: Merge __hrtimer_init() into __hrtimer_setup()
hrtimers: Switch to use __htimer_setup()
hrtimers: Delete hrtimer_init()
treewide: Convert new and leftover hrtimer_init() users
treewide: Switch/rename to timer_delete[_sync]()
