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/* SPDX-License-Identifier: MIT */
/*
* Copyright © 2019 Intel Corporation
*/
#ifndef __I915_MEMCPY_H__
#define __I915_MEMCPY_H__
#include <linux/types.h>
struct drm_i915_private;
void i915_memcpy_init_early(struct drm_i915_private *i915);
bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len);
/* The movntdqa instructions used for memcpy-from-wc require 16-byte alignment,
* as well as SSE4.1 support. i915_memcpy_from_wc() will report if it cannot
* perform the operation. To check beforehand, pass in the parameters to
* to i915_can_memcpy_from_wc() - since we only care about the low 4 bits,
* you only need to pass in the minor offsets, page-aligned pointers are
* always valid.
*
* For just checking for SSE4.1, in the foreknowledge that the future use
* will be correctly aligned, just use i915_has_memcpy_from_wc().
*/
#define i915_can_memcpy_from_wc(dst, src, len) \
i915_memcpy_from_wc((void *)((unsigned long)(dst) | (unsigned long)(src) | (len)), NULL, 0)
#define i915_has_memcpy_from_wc() \
i915_memcpy_from_wc(NULL, NULL, 0)
#endif /* __I915_MEMCPY_H__ */
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