kernel/linux.git/include/uapi/drm/panthor_drm.h, branch v6.12.80

drm/panthor: Add missing explicit padding in drm_panthor_gpu_info

2025-08-15T10:13:39+00:00

[ Upstream commit 95cbab48782bf62e4093837dc15ac6133902c12f ] 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: 0f25e493a246 ("drm/panthor: Add uAPI") Acked-by: Liviu Dudau Reviewed-by: Adrián Larumbe Reviewed-by: Steven Price Link: https://lore.kernel.org/r/20250606080932.4140010-2-boris.brezillon@collabora.com Signed-off-by: Boris Brezillon Signed-off-by: Sasha Levin

drm/panthor: Restrict high priorities on group_create

2024-09-05T07:33:33+00:00

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]https://gitlab.freedesktop.org/mesa/mesa/-/blob/f390835074bdf162a63deb0311d1a6de527f9f89/src/gallium/drivers/panfrost/pan_csf.c#L1038 Signed-off-by: Mary Guillemard Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") Cc: stable@vger.kernel.org Reviewed-by: Boris Brezillon Signed-off-by: Boris Brezillon Link: https://patchwork.freedesktop.org/patch/msgid/20240903144955.144278-2-mary.guillemard@collabora.com

drm/panthor: Fix sync-only jobs

2024-07-03T07:45:36+00:00

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: de8548813824 ("drm/panthor: Add the scheduler logical block") Signed-off-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20240703071640.231278-3-boris.brezillon@collabora.com

drm/panthor: Document drm_panthor_tiler_heap_destroy::handle validity constraints

2024-05-13T07:49:25+00:00

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 Reviewed-by: Steven Price Reviewed-by: Liviu Dudau Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-6-boris.brezillon@collabora.com

drm/panthor: Relax the constraints on the tiler chunk size

2024-05-13T07:49:19+00:00

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: 9cca48fa4f89 ("drm/panthor: Add the heap logical block") Signed-off-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-4-boris.brezillon@collabora.com

drm/panthor: Make sure the tiler initial/max chunks are consistent

2024-05-13T07:49:15+00:00

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: 9cca48fa4f89 ("drm/panthor: Add the heap logical block") Signed-off-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20240502165158.1458959-3-boris.brezillon@collabora.com

drm/panthor: Fix wrong kernel-doc format in the uAPI header

2024-03-26T10:57:39+00:00

The kernel doc prefix is /** not /*. Reported-by: Stephen Rothwell Signed-off-by: Boris Brezillon Acked-by: Liviu Dudau Link: https://patchwork.freedesktop.org/patch/msgid/20240326093055.411932-1-boris.brezillon@collabora.com

drm/panthor: Add uAPI

2024-03-01T09:03:59+00:00

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 Signed-off-by: Steven Price Signed-off-by: Boris Brezillon Reviewed-by: Steven Price Reviewed-by: Liviu Dudau Acked-by: Maxime Ripard Acked-by: Heiko Stuebner Link: https://patchwork.freedesktop.org/patch/msgid/20240229162230.2634044-2-boris.brezillon@collabora.com