1/* SPDX-License-Identifier: MIT */
2/*
3 * Copyright © 2019 Intel Corporation
4 */
5
6#ifndef __I915_MEMCPY_H__
7#define __I915_MEMCPY_H__
8
9#include <linux/types.h>
10
11struct drm_i915_private;
12
13void i915_memcpy_init_early(struct drm_i915_private *i915);
14
15bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len);
16void i915_unaligned_memcpy_from_wc(void *dst, const void *src, unsigned long len);
17
18/* The movntdqa instructions used for memcpy-from-wc require 16-byte alignment,
19 * as well as SSE4.1 support. i915_memcpy_from_wc() will report if it cannot
20 * perform the operation. To check beforehand, pass in the parameters to
21 * to i915_can_memcpy_from_wc() - since we only care about the low 4 bits,
22 * you only need to pass in the minor offsets, page-aligned pointers are
23 * always valid.
24 *
25 * For just checking for SSE4.1, in the foreknowledge that the future use
26 * will be correctly aligned, just use i915_has_memcpy_from_wc().
27 */
28#define i915_can_memcpy_from_wc(dst, src, len) \
29 i915_memcpy_from_wc((void *)((unsigned long)(dst) | (unsigned long)(src) | (len)), NULL, 0)
30
31#define i915_has_memcpy_from_wc() \
32 i915_memcpy_from_wc(NULL, NULL, 0)
33
34#endif /* __I915_MEMCPY_H__ */
35