[Intel-gfx] [RFC 2/2] drm/doc/rfc: VM_BIND uapi definition

[Niranjana Vishwanathapura]

VM_BIND and GEM_WAIT_USER_FENCE uapi document

Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura at intel.com>
---
 Documentation/gpu/rfc/i915_vm_bind.h   | 113 +++++++++++++++++++++++++
 Documentation/gpu/rfc/i915_vm_bind.rst |   6 ++
 2 files changed, 119 insertions(+)
 create mode 100644 Documentation/gpu/rfc/i915_vm_bind.h

diff --git a/Documentation/gpu/rfc/i915_vm_bind.h b/Documentation/gpu/rfc/i915_vm_bind.h
new file mode 100644
index 000000000000..3aaf66e62aa0
--- /dev/null
+++ b/Documentation/gpu/rfc/i915_vm_bind.h
@@ -0,0 +1,113 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2021 Intel Corporation
+ */
+
+/* VM_BIND feature availability through drm_i915_getparam */
+#define I915_PARAM_HAS_VM_BIND          59
+
+/**
+ * struct drm_i915_gem_vm_bind - VA to object/buffer mapping to [un]bind.
+ */
+struct drm_i915_gem_vm_bind {
+	/** vm to [un]bind **/
+	__u32 vm_id;
+
+	/** BO handle or file descriptor. 'fd' to -1 for system pages (SVM) **/
+	union {
+		__u32 handle;
+		__s32 fd;
+	}
+
+	/** VA start to [un]bind **/
+	__u64 start;
+
+	/** Offset in object to [un]bind **/
+	__u64 offset;
+
+	/** VA length to [un]bind **/
+	__u64 length;
+
+	/** Flags **/
+	__u64 flags;
+	/** Bind the mapping immediately instead of during next submission */
+#define I915_GEM_VM_BIND_IMMEDIATE   (1 << 0)
+	/** Read-only mapping */
+#define I915_GEM_VM_BIND_READONLY    (1 << 1)
+	/** Capture this mapping in the dump upon GPU error */
+#define I915_GEM_VM_BIND_CAPTURE     (1 << 2)
+
+	/**
+	 * Zero-terminated chain of extensions.
+	 *
+	 * No current extensions defined; mbz.
+	 */
+	__u64 extensions;
+};
+
+/**
+ * struct drm_i915_vm_bind_ext_sync_fence - Bind completion signaling extension.
+ */
+struct drm_i915_vm_bind_ext_sync_fence {
+#define I915_VM_BIND_EXT_SYNC_FENCE     0
+	/** @base: Extension link. See struct i915_user_extension. */
+	struct i915_user_extension base;
+
+	/** User/Memory fence address */
+	__u64 addr;
+
+	/** User/Memory fence value to be written after bind completion */
+	__u64 val;
+};
+
+/**
+ * struct drm_i915_gem_wait_user_fence
+ *
+ * Wait on user/memory fence. User/Memory fence can be woken up either by,
+ *    1. GPU context indicated by 'ctx_id', or,
+ *    2. Kerrnel driver async worker upon I915_UFENCE_WAIT_SOFT.
+ *       'ctx_id' is ignored when this flag is set.
+ *
+ * Wakeup when below condition is true.
+ * (*addr & MASK) OP (VALUE & MASK)
+ *
+ */
+struct drm_i915_gem_wait_user_fence {
+	/** @base: Extension link. See struct i915_user_extension. */
+	__u64 extensions;
+
+	/** User/Memory fence address */
+	__u64 addr;
+
+	/** Id of the Context which will signal the fence. */
+	__u32 ctx_id;
+
+	/** Wakeup condition operator */
+	__u16 op;
+#define I915_UFENCE_WAIT_EQ      0
+#define I915_UFENCE_WAIT_NEQ     1
+#define I915_UFENCE_WAIT_GT      2
+#define I915_UFENCE_WAIT_GTE     3
+#define I915_UFENCE_WAIT_LT      4
+#define I915_UFENCE_WAIT_LTE     5
+#define I915_UFENCE_WAIT_BEFORE  6
+#define I915_UFENCE_WAIT_AFTER   7
+
+	/** Flags */
+	__u16 flags;
+#define I915_UFENCE_WAIT_SOFT    0x1
+#define I915_UFENCE_WAIT_ABSTIME 0x2
+
+	/** Wakeup value */
+	__u64 value;
+
+	/** Wakeup mask */
+	__u64 mask;
+#define I915_UFENCE_WAIT_U8     0xffu
+#define I915_UFENCE_WAIT_U16    0xffffu
+#define I915_UFENCE_WAIT_U32    0xfffffffful
+#define I915_UFENCE_WAIT_U64    0xffffffffffffffffull
+
+	/** Timeout */
+	__s64 timeout;
+};
diff --git a/Documentation/gpu/rfc/i915_vm_bind.rst b/Documentation/gpu/rfc/i915_vm_bind.rst
index dbc35262a554..dc843e32a1cd 100644
--- a/Documentation/gpu/rfc/i915_vm_bind.rst
+++ b/Documentation/gpu/rfc/i915_vm_bind.rst
@@ -117,6 +117,12 @@ VM_BIND interface can be used to map system memory directly (without gem BO
 abstraction) using the HMM interface.
 
 
+UAPI
+=====
+Uapi definiton can be found here:
+.. kernel-doc:: Documentation/gpu/rfc/i915_vm_bind.h
+
+
 Links:
 ======
 - Reference WIP VM_BIND implementation can be found here.
-- 
2.21.0.rc0.32.g243a4c7e27