Currently, we pick the MMIO offset based on the size of the pgoff_t
type seen by the process that manipulates the FD, such that a 32-bit
process can always map the user MMIO ranges. But this approach doesn't
work well for emulators like FEX, where the emulator is a 64-bit binary
which might be executing 32-bit code. In that case, the kernel thinks
it's the 64-bit process and assumes DRM_PANTHOR_USER_MMIO_OFFSET_64BIT
is in use, but the UMD library expects DRM_PANTHOR_USER_MMIO_OFFSET_32BIT,
because it can't mmap() anything above the pgoff_t size.
In order to solve that, we need a way to explicitly set the user MMIO
offset from the UMD, such that the kernel doesn't have to guess it
from the TIF_32BIT flag set on user thread. We keep the old behavior
if DRM_PANTHOR_SET_USER_MMIO_OFFSET is never called.
Changes in v2:
- Drop the lock/immutable fields and allow SET_USER_MMIO_OFFSET
requests to race with mmap() requests
- Don't do the is_user_mmio_offset test twice in panthor_mmap()
- Improve the uAPI docs
Changes in v3:
- Bump to version 1.5 instead of 1.4 after rebasing
- Add R-bs
- Fix/rephrase comment as suggested by Liviu
Reviewed-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://lore.kernel.org/r/20250606080932.4140010-3-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
drm_panthor_gpu_info::shader_present is currently automatically offset
by 4 byte to meet Arm's 32-bit/64-bit field alignment rules, but those
constraints don't stand on 32-bit x86 and cause a mismatch when running
an x86 binary in a user emulated environment like FEX. It's also
generally agreed that uAPIs should explicitly pad their struct fields,
which we originally intended to do, but a mistake slipped through during
the submission process, leading drm_panthor_gpu_info::shader_present to
be misaligned.
This uAPI change doesn't break any of the existing users of panthor
which are either arm32 or arm64 where the 64-bit alignment of
u64 fields is already enforced a the compiler level.
Changes in v2:
- Rename the garbage field into pad0 and adjust the comment accordingly
- Add Liviu's A-b
Changes in v3:
- Add R-bs
Fixes: 0f25e493a2 ("drm/panthor: Add uAPI")
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20250606080932.4140010-2-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Allow UM to label a BO for which it possesses a DRM handle.
Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20250423021238.1639175-3-adrian.larumbe@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Use an enum instead of #defines for panthor IOCTLs. This allows the
header to be used with Rust code as bindgen can't handle complex
defines.
Cc: Beata Michalska <beata.michalska@arm.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250204232824.3819437-1-robh@kernel.org
Groups can be killed during a reset even though they did nothing wrong.
That usually happens when the FW is put in a bad state by other groups,
resulting in group suspension failures when the reset happens.
If we end up in that situation, flag the group innocent and report
innocence through a new DRM_PANTHOR_GROUP_STATE flag.
Bump the minor driver version to reflect the uAPI change.
Changes in v4:
- Add an entry to the driver version changelog
- Add R-bs
Changes in v3:
- Actually report innocence to userspace
Changes in v2:
- New patch
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241211080500.2349505-1-boris.brezillon@collabora.com
Expose allowed group priorities with a new device query.
This new uAPI will be used in Mesa to properly report what priorities a
user can use for EGL_IMG_context_priority.
Since this extends the uAPI and because userland needs a way to
advertise priorities accordingly, this also bumps the driver minor
version.
v2:
- Remove drm_panthor_group_allow_priority_flags definition
- Document that allowed_mask is a bitmask of drm_panthor_group_priority
v3:
- Use BIT macro in panthor_query_group_priorities_info
- Add r-b from Steven Price and Boris Brezillon
Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240909064820.34982-4-mary.guillemard@collabora.com
This adds a new value to drm_panthor_group_priority exposing the
realtime priority to userspace.
This is required to implement NV_context_priority_realtime in Mesa.
v2:
- Add Steven Price r-b
v3:
- Add Boris Brezillon r-b
Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240909064820.34982-3-mary.guillemard@collabora.com
Expose timestamp information supported by the GPU with a new device
query.
Mali uses an external timer as GPU system time. On ARM, this is wired to
the generic arch timer so we wire cntfrq_el0 as device frequency.
This new uAPI will be used in Mesa to implement timestamp queries and
VK_KHR_calibrated_timestamps.
Since this extends the uAPI and because userland needs a way to advertise
those features conditionally, this also bumps the driver minor version.
v2:
- Rewrote to use GPU timestamp register
- Added timestamp_offset to drm_panthor_timestamp_info
- Add missing include for arch_timer_get_cntfrq
- Rework commit message
v3:
- Add panthor_gpu_read_64bit_counter
- Change panthor_gpu_read_timestamp to use
panthor_gpu_read_64bit_counter
v4:
- Fix multiple typos in uAPI documentation
- Mention behavior when the timestamp frequency is unknown
- Use u64 instead of unsigned long long
for panthor_gpu_read_timestamp
- Apply r-b from Mihail
Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Reviewed-by: Mihail Atanassov <mihail.atanassov@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240830080349.24736-2-mary.guillemard@collabora.com
We were allowing any users to create a high priority group without any
permission checks. As a result, this was allowing possible denial of
service.
We now only allow the DRM master or users with the CAP_SYS_NICE
capability to set higher priorities than PANTHOR_GROUP_PRIORITY_MEDIUM.
As the sole user of that uAPI lives in Mesa and hardcode a value of
MEDIUM [1], this should be safe to do.
Additionally, as those checks are performed at the ioctl level,
panthor_group_create now only check for priority level validity.
[1]f390835074/src/gallium/drivers/panfrost/pan_csf.c (L1038)
Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Fixes: de85488138 ("drm/panthor: Add the scheduler logical block")
Cc: stable@vger.kernel.org
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240903144955.144278-2-mary.guillemard@collabora.com
A sync-only job is meant to provide a synchronization point on a
queue, so we can't return a NULL fence there, we have to add a signal
operation to the command stream which executes after all other
previously submitted jobs are done.
v2:
- Fixed a UAF bug
- Added R-bs
Fixes: de85488138 ("drm/panthor: Add the scheduler logical block")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240703071640.231278-3-boris.brezillon@collabora.com
Make sure the user is aware that drm_panthor_tiler_heap_destroy::handle
must be a handle previously returned by
DRM_IOCTL_PANTHOR_TILER_HEAP_CREATE.
v4:
- Add Steve's R-b
v3:
- New patch
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-6-boris.brezillon@collabora.com
The field used to store the chunk size if 12 bits wide, and the encoding
is chunk_size = chunk_header.chunk_size << 12, which gives us a
theoretical [4k:8M] range. This range is further limited by
implementation constraints, and all known implementations seem to
impose a [128k:8M] range, so do the same here.
We also relax the power-of-two constraint, which doesn't seem to
exist on v10. This will allow userspace to fine-tune initial/max
tiler memory on memory-constrained devices.
v4:
- Actually fix the range in the kerneldoc
v3:
- Add R-bs
- Fix valid range in the kerneldoc
v2:
- Turn the power-of-two constraint into a page-aligned constraint to allow
fine-tune of the initial/max heap memory size
- Fix the panthor_heap_create() kerneldoc
Fixes: 9cca48fa4f ("drm/panthor: Add the heap logical block")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-4-boris.brezillon@collabora.com
It doesn't make sense to have a maximum number of chunks smaller than
the initial number of chunks attached to the context.
Fix the uAPI header to reflect the new constraint, and mention the
undocumented "initial_chunk_count > 0" constraint while at it.
v3:
- Add R-b
v2:
- Fix the check
Fixes: 9cca48fa4f ("drm/panthor: Add the heap logical block")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-3-boris.brezillon@collabora.com
Panthor follows the lead of other recently submitted drivers with
ioctls allowing us to support modern Vulkan features, like sparse memory
binding:
- Pretty standard GEM management ioctls (BO_CREATE and BO_MMAP_OFFSET),
with the 'exclusive-VM' bit to speed-up BO reservation on job submission
- VM management ioctls (VM_CREATE, VM_DESTROY and VM_BIND). The VM_BIND
ioctl is loosely based on the Xe model, and can handle both
asynchronous and synchronous requests
- GPU execution context creation/destruction, tiler heap context creation
and job submission. Those ioctls reflect how the hardware/scheduler
works and are thus driver specific.
We also have a way to expose IO regions, such that the usermode driver
can directly access specific/well-isolate registers, like the
LATEST_FLUSH register used to implement cache-flush reduction.
This uAPI intentionally keeps usermode queues out of the scope, which
explains why doorbell registers and command stream ring-buffers are not
directly exposed to userspace.
v6:
- Add Maxime's and Heiko's acks
v5:
- Fix typo
- Add Liviu's R-b
v4:
- Add a VM_GET_STATE ioctl
- Fix doc
- Expose the CORE_FEATURES register so we can deal with variants in the
UMD
- Add Steve's R-b
v3:
- Add the concept of sync-only VM operation
- Fix support for 32-bit userspace
- Rework drm_panthor_vm_create to pass the user VA size instead of
the kernel VA size (suggested by Robin Murphy)
- Typo fixes
- Explicitly cast enums with top bit set to avoid compiler warnings in
-pedantic mode.
- Drop property core_group_count as it can be easily calculated by the
number of bits set in l2_present.
Co-developed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20240229162230.2634044-2-boris.brezillon@collabora.com