| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 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 | |
| 11 | struct drm_i915_private; |
| 12 | |
| 13 | void i915_memcpy_init_early(struct drm_i915_private *i915); |
| 14 | bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len); |
| 15 | |
| 16 | /* The movntdqa instructions used for memcpy-from-wc require 16-byte alignment, |
| 17 | * as well as SSE4.1 support. i915_memcpy_from_wc() will report if it cannot |
| 18 | * perform the operation. To check beforehand, pass in the parameters to |
| 19 | * to i915_can_memcpy_from_wc() - since we only care about the low 4 bits, |
| 20 | * you only need to pass in the minor offsets, page-aligned pointers are |
| 21 | * always valid. |
| 22 | * |
| 23 | * For just checking for SSE4.1, in the foreknowledge that the future use |
| 24 | * will be correctly aligned, just use i915_has_memcpy_from_wc(). |
| 25 | */ |
| 26 | #define i915_can_memcpy_from_wc(dst, src, len) \ |
| 27 | i915_memcpy_from_wc((void *)((unsigned long)(dst) | (unsigned long)(src) | (len)), NULL, 0) |
| 28 | |
| 29 | #define i915_has_memcpy_from_wc() \ |
| 30 | i915_memcpy_from_wc(NULL, NULL, 0) |
| 31 | |
| 32 | #endif /* __I915_MEMCPY_H__ */ |