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1/* SPDX-License-Identifier: MIT */2/*3 * Copyright © 2019 Intel Corporation4 */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 cannot20 * perform the operation. To check beforehand, pass in the parameters to21 * 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 are23 * always valid.24 *25 * For just checking for SSE4.1, in the foreknowledge that the future use26 * 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