[PATCH drm-next v6 04/13] drm/nouveau: new VM_BIND uapi interfaces

From: Danilo Krummrich
Date: Thu Jun 29 2023 - 18:29:05 EST

This commit provides the interfaces for the new UAPI motivated by the
Vulkan API. It allows user mode drivers (UMDs) to:

1) Initialize a GPU virtual address (VA) space via the new
DRM_IOCTL_NOUVEAU_VM_INIT ioctl. UMDs can provide a kernel reserved
VA area.

2) Bind and unbind GPU VA space mappings via the new
DRM_IOCTL_NOUVEAU_VM_BIND ioctl.

3) Execute push buffers with the new DRM_IOCTL_NOUVEAU_EXEC ioctl.

Both, DRM_IOCTL_NOUVEAU_VM_BIND and DRM_IOCTL_NOUVEAU_EXEC support
asynchronous processing with DRM syncobjs as synchronization mechanism.

The default DRM_IOCTL_NOUVEAU_VM_BIND is synchronous processing,
DRM_IOCTL_NOUVEAU_EXEC supports asynchronous processing only.

Co-authored-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
---
Documentation/gpu/driver-uapi.rst | 8 ++
include/uapi/drm/nouveau_drm.h | 209 ++++++++++++++++++++++++++++++
2 files changed, 217 insertions(+)

diff --git a/Documentation/gpu/driver-uapi.rst b/Documentation/gpu/driver-uapi.rst
index 4411e6919a3d..9c7ca6e33a68 100644
--- a/Documentation/gpu/driver-uapi.rst
+++ b/Documentation/gpu/driver-uapi.rst
@@ -6,3 +6,11 @@ drm/i915 uAPI
=============

.. kernel-doc:: include/uapi/drm/i915_drm.h
+
+drm/nouveau uAPI
+================
+
+VM_BIND / EXEC uAPI
+-------------------
+
+.. kernel-doc:: include/uapi/drm/nouveau_drm.h
diff --git a/include/uapi/drm/nouveau_drm.h b/include/uapi/drm/nouveau_drm.h
index 853a327433d3..4d3a70529637 100644
--- a/include/uapi/drm/nouveau_drm.h
+++ b/include/uapi/drm/nouveau_drm.h
@@ -126,6 +126,209 @@ struct drm_nouveau_gem_cpu_fini {
__u32 handle;
};

+/**
+ * struct drm_nouveau_sync - sync object
+ *
+ * This structure serves as synchronization mechanism for (potentially)
+ * asynchronous operations such as EXEC or VM_BIND.
+ */
+struct drm_nouveau_sync {
+ /**
+ * @flags: the flags for a sync object
+ *
+ * The first 8 bits are used to determine the type of the sync object.
+ */
+ __u32 flags;
+#define DRM_NOUVEAU_SYNC_SYNCOBJ 0x0
+#define DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ 0x1
+#define DRM_NOUVEAU_SYNC_TYPE_MASK 0xf
+ /**
+ * @handle: the handle of the sync object
+ */
+ __u32 handle;
+ /**
+ * @timeline_value:
+ *
+ * The timeline point of the sync object in case the syncobj is of
+ * type DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ.
+ */
+ __u64 timeline_value;
+};
+
+/**
+ * struct drm_nouveau_vm_init - GPU VA space init structure
+ *
+ * Used to initialize the GPU's VA space for a user client, telling the kernel
+ * which portion of the VA space is managed by the UMD and kernel respectively.
+ */
+struct drm_nouveau_vm_init {
+ /**
+ * @unmanaged_addr: start address of the kernel managed VA space region
+ */
+ __u64 unmanaged_addr;
+ /**
+ * @unmanaged_size: size of the kernel managed VA space region in bytes
+ */
+ __u64 unmanaged_size;
+};
+
+/**
+ * struct drm_nouveau_vm_bind_op - VM_BIND operation
+ *
+ * This structure represents a single VM_BIND operation. UMDs should pass
+ * an array of this structure via struct drm_nouveau_vm_bind's &op_ptr field.
+ */
+struct drm_nouveau_vm_bind_op {
+ /**
+ * @op: the operation type
+ */
+ __u32 op;
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_MAP:
+ *
+ * Map a GEM object to the GPU's VA space. Optionally, the
+ * &DRM_NOUVEAU_VM_BIND_SPARSE flag can be passed to instruct the kernel to
+ * create sparse mappings for the given range.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_MAP 0x0
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_UNMAP:
+ *
+ * Unmap an existing mapping in the GPU's VA space. If the region the mapping
+ * is located in is a sparse region, new sparse mappings are created where the
+ * unmapped (memory backed) mapping was mapped previously. To remove a sparse
+ * region the &DRM_NOUVEAU_VM_BIND_SPARSE must be set.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_UNMAP 0x1
+ /**
+ * @flags: the flags for a &drm_nouveau_vm_bind_op
+ */
+ __u32 flags;
+/**
+ * @DRM_NOUVEAU_VM_BIND_SPARSE:
+ *
+ * Indicates that an allocated VA space region should be sparse.
+ */
+#define DRM_NOUVEAU_VM_BIND_SPARSE (1 << 8)
+ /**
+ * @handle: the handle of the DRM GEM object to map
+ */
+ __u32 handle;
+ /**
+ * @pad: 32 bit padding, should be 0
+ */
+ __u32 pad;
+ /**
+ * @addr:
+ *
+ * the address the VA space region or (memory backed) mapping should be mapped to
+ */
+ __u64 addr;
+ /**
+ * @bo_offset: the offset within the BO backing the mapping
+ */
+ __u64 bo_offset;
+ /**
+ * @range: the size of the requested mapping in bytes
+ */
+ __u64 range;
+};
+
+/**
+ * struct drm_nouveau_vm_bind - structure for DRM_IOCTL_NOUVEAU_VM_BIND
+ */
+struct drm_nouveau_vm_bind {
+ /**
+ * @op_count: the number of &drm_nouveau_vm_bind_op
+ */
+ __u32 op_count;
+ /**
+ * @flags: the flags for a &drm_nouveau_vm_bind ioctl
+ */
+ __u32 flags;
+/**
+ * @DRM_NOUVEAU_VM_BIND_RUN_ASYNC:
+ *
+ * Indicates that the given VM_BIND operation should be executed asynchronously
+ * by the kernel.
+ *
+ * If this flag is not supplied the kernel executes the associated operations
+ * synchronously and doesn't accept any &drm_nouveau_sync objects.
+ */
+#define DRM_NOUVEAU_VM_BIND_RUN_ASYNC 0x1
+ /**
+ * @wait_count: the number of wait &drm_nouveau_syncs
+ */
+ __u32 wait_count;
+ /**
+ * @sig_count: the number of &drm_nouveau_syncs to signal when finished
+ */
+ __u32 sig_count;
+ /**
+ * @wait_ptr: pointer to &drm_nouveau_syncs to wait for
+ */
+ __u64 wait_ptr;
+ /**
+ * @sig_ptr: pointer to &drm_nouveau_syncs to signal when finished
+ */
+ __u64 sig_ptr;
+ /**
+ * @op_ptr: pointer to the &drm_nouveau_vm_bind_ops to execute
+ */
+ __u64 op_ptr;
+};
+
+/**
+ * struct drm_nouveau_exec_push - EXEC push operation
+ *
+ * This structure represents a single EXEC push operation. UMDs should pass an
+ * array of this structure via struct drm_nouveau_exec's &push_ptr field.
+ */
+struct drm_nouveau_exec_push {
+ /**
+ * @va: the virtual address of the push buffer mapping
+ */
+ __u64 va;
+ /**
+ * @va_len: the length of the push buffer mapping
+ */
+ __u64 va_len;
+};
+
+/**
+ * struct drm_nouveau_exec - structure for DRM_IOCTL_NOUVEAU_EXEC
+ */
+struct drm_nouveau_exec {
+ /**
+ * @channel: the channel to execute the push buffer in
+ */
+ __u32 channel;
+ /**
+ * @push_count: the number of &drm_nouveau_exec_push ops
+ */
+ __u32 push_count;
+ /**
+ * @wait_count: the number of wait &drm_nouveau_syncs
+ */
+ __u32 wait_count;
+ /**
+ * @sig_count: the number of &drm_nouveau_syncs to signal when finished
+ */
+ __u32 sig_count;
+ /**
+ * @wait_ptr: pointer to &drm_nouveau_syncs to wait for
+ */
+ __u64 wait_ptr;
+ /**
+ * @sig_ptr: pointer to &drm_nouveau_syncs to signal when finished
+ */
+ __u64 sig_ptr;
+ /**
+ * @push_ptr: pointer to &drm_nouveau_exec_push ops
+ */
+ __u64 push_ptr;
+};
+
#define DRM_NOUVEAU_GETPARAM 0x00 /* deprecated */
#define DRM_NOUVEAU_SETPARAM 0x01 /* deprecated */
#define DRM_NOUVEAU_CHANNEL_ALLOC 0x02 /* deprecated */
@@ -136,6 +339,9 @@ struct drm_nouveau_gem_cpu_fini {
#define DRM_NOUVEAU_NVIF 0x07
#define DRM_NOUVEAU_SVM_INIT 0x08
#define DRM_NOUVEAU_SVM_BIND 0x09
+#define DRM_NOUVEAU_VM_INIT 0x10
+#define DRM_NOUVEAU_VM_BIND 0x11
+#define DRM_NOUVEAU_EXEC 0x12
#define DRM_NOUVEAU_GEM_NEW 0x40
#define DRM_NOUVEAU_GEM_PUSHBUF 0x41
#define DRM_NOUVEAU_GEM_CPU_PREP 0x42
@@ -197,6 +403,9 @@ struct drm_nouveau_svm_bind {
#define DRM_IOCTL_NOUVEAU_GEM_CPU_FINI DRM_IOW (DRM_COMMAND_BASE + DRM_NOUVEAU_GEM_CPU_FINI, struct drm_nouveau_gem_cpu_fini)
#define DRM_IOCTL_NOUVEAU_GEM_INFO DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_GEM_INFO, struct drm_nouveau_gem_info)

+#define DRM_IOCTL_NOUVEAU_VM_INIT DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_VM_INIT, struct drm_nouveau_vm_init)
+#define DRM_IOCTL_NOUVEAU_VM_BIND DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_VM_BIND, struct drm_nouveau_vm_bind)
+#define DRM_IOCTL_NOUVEAU_EXEC DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_EXEC, struct drm_nouveau_exec)
#if defined(__cplusplus)
}
#endif
--
2.41.0