Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/panthor: Add an ioctl to query BO flags
This is useful when importing BOs, so we can know about cacheability
and flush the caches when needed.
We can also know when the buffer comes from a different subsystem and
take proper actions (avoid CPU mappings, or do kernel-based syncs
instead of userland cache flushes).
v2:
- New commit
v3:
- Add Steve's R-b
v4:
- No changes
v5:
- No changes
v6:
- No changes
v7:
- No changes
v8:
- No changes
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251208100841.730527-6-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
+81
+24
drivers/gpu/drm/panthor/panthor_drv.c
+24
drivers/gpu/drm/panthor/panthor_drv.c
···
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return ret;
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}
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+
static int panthor_ioctl_bo_query_info(struct drm_device *ddev, void *data,
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struct drm_file *file)
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{
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struct drm_panthor_bo_query_info *args = data;
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struct panthor_gem_object *bo;
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struct drm_gem_object *obj;
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+
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obj = drm_gem_object_lookup(file, args->handle);
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if (!obj)
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return -ENOENT;
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+
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bo = to_panthor_bo(obj);
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args->pad = 0;
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args->create_flags = bo->flags;
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+
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args->extra_flags = 0;
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if (drm_gem_is_imported(&bo->base.base))
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args->extra_flags |= DRM_PANTHOR_BO_IS_IMPORTED;
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+
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drm_gem_object_put(obj);
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return 0;
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}
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+
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static int
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panthor_open(struct drm_device *ddev, struct drm_file *file)
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{
···
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PANTHOR_IOCTL(BO_SET_LABEL, bo_set_label, DRM_RENDER_ALLOW),
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PANTHOR_IOCTL(SET_USER_MMIO_OFFSET, set_user_mmio_offset, DRM_RENDER_ALLOW),
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PANTHOR_IOCTL(BO_SYNC, bo_sync, DRM_RENDER_ALLOW),
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PANTHOR_IOCTL(BO_QUERY_INFO, bo_query_info, DRM_RENDER_ALLOW),
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};
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static int panthor_mmap(struct file *filp, struct vm_area_struct *vma)
+57
include/uapi/drm/panthor_drm.h
+57
include/uapi/drm/panthor_drm.h
···
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/** @DRM_PANTHOR_BO_SYNC: Sync BO data to/from the device */
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DRM_PANTHOR_BO_SYNC,
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+
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/**
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* @DRM_PANTHOR_BO_QUERY_INFO: Query information about a BO.
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*
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* This is useful for imported BOs.
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*/
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DRM_PANTHOR_BO_QUERY_INFO,
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};
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/**
···
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};
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/**
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* enum drm_panthor_bo_extra_flags - Set of flags returned on a BO_QUERY_INFO request
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*
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* Those are flags reflecting BO properties that are not directly coming from the flags
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* passed are creation time, or information on BOs that were imported from other drivers.
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*/
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enum drm_panthor_bo_extra_flags {
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/**
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* @DRM_PANTHOR_BO_IS_IMPORTED: BO has been imported from an external driver.
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*
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* Note that imported dma-buf handles are not flagged as imported if they
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* where exported by panthor. Only buffers that are coming from other drivers
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* (dma heaps, other GPUs, display controllers, V4L, ...).
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*
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* It's also important to note that all imported BOs are mapped cached and can't
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* be considered IO-coherent even if the GPU is. This means they require explicit
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* syncs that must go through the DRM_PANTHOR_BO_SYNC ioctl (userland cache
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* maintenance is not allowed in that case, because extra operations might be
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* needed to make changes visible to the CPU/device, like buffer migration when the
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* exporter is a GPU with its own VRAM).
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*/
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DRM_PANTHOR_BO_IS_IMPORTED = (1 << 0),
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};
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+
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/**
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* struct drm_panthor_bo_query_info - Query BO info
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*/
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struct drm_panthor_bo_query_info {
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/** @handle: Handle of the buffer object to query flags on. */
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__u32 handle;
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+
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/**
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* @extra_flags: Combination of enum drm_panthor_bo_extra_flags flags.
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*/
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__u32 extra_flags;
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+
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/**
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* @create_flags: Flags passed at creation time.
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*
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* Combination of enum drm_panthor_bo_flags flags.
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* Will be zero if the buffer comes from a different driver.
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*/
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__u32 create_flags;
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/** @pad: Will be zero on return. */
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__u32 pad;
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};
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/**
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* DRM_IOCTL_PANTHOR() - Build a Panthor IOCTL number
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* @__access: Access type. Must be R, W or RW.
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* @__id: One of the DRM_PANTHOR_xxx id.
···
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DRM_IOCTL_PANTHOR(WR, SET_USER_MMIO_OFFSET, set_user_mmio_offset),
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DRM_IOCTL_PANTHOR_BO_SYNC =
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DRM_IOCTL_PANTHOR(WR, BO_SYNC, bo_sync),
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DRM_IOCTL_PANTHOR_BO_QUERY_INFO =
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DRM_IOCTL_PANTHOR(WR, BO_QUERY_INFO, bo_query_info),
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};
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#if defined(__cplusplus)