1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3 * Copyright 2020 Advanced Micro Devices, Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 *
23 * Authors: Christian König
24 */
25
26 #ifndef __AMDGPU_RES_CURSOR_H__
27 #define __AMDGPU_RES_CURSOR_H__
28
29 #include <drm/drm_mm.h>
30 #include <drm/ttm/ttm_resource.h>
31 #include <drm/ttm/ttm_range_manager.h>
32
33 /* state back for walking over vram_mgr and gtt_mgr allocations */
34 struct amdgpu_res_cursor {
35 uint64_t start;
36 uint64_t size;
37 uint64_t remaining;
38 struct drm_mm_node *node;
39 };
40
41 /**
42 * amdgpu_res_first - initialize a amdgpu_res_cursor
43 *
44 * @res: TTM resource object to walk
45 * @start: Start of the range
46 * @size: Size of the range
47 * @cur: cursor object to initialize
48 *
49 * Start walking over the range of allocations between @start and @size.
50 */
amdgpu_res_first(struct ttm_resource * res,uint64_t start,uint64_t size,struct amdgpu_res_cursor * cur)51 static inline void amdgpu_res_first(struct ttm_resource *res,
52 uint64_t start, uint64_t size,
53 struct amdgpu_res_cursor *cur)
54 {
55 struct drm_mm_node *node;
56
57 if (!res || res->mem_type == TTM_PL_SYSTEM) {
58 cur->start = start;
59 cur->size = size;
60 cur->remaining = size;
61 cur->node = NULL;
62 WARN_ON(res && start + size > res->num_pages << PAGE_SHIFT);
63 return;
64 }
65
66 BUG_ON(start + size > res->num_pages << PAGE_SHIFT);
67
68 node = to_ttm_range_mgr_node(res)->mm_nodes;
69 while (start >= node->size << PAGE_SHIFT)
70 start -= node++->size << PAGE_SHIFT;
71
72 cur->start = (node->start << PAGE_SHIFT) + start;
73 cur->size = min((node->size << PAGE_SHIFT) - start, size);
74 cur->remaining = size;
75 cur->node = node;
76 }
77
78 /**
79 * amdgpu_res_next - advance the cursor
80 *
81 * @cur: the cursor to advance
82 * @size: number of bytes to move forward
83 *
84 * Move the cursor @size bytes forwrad, walking to the next node if necessary.
85 */
amdgpu_res_next(struct amdgpu_res_cursor * cur,uint64_t size)86 static inline void amdgpu_res_next(struct amdgpu_res_cursor *cur, uint64_t size)
87 {
88 struct drm_mm_node *node = cur->node;
89
90 BUG_ON(size > cur->remaining);
91
92 cur->remaining -= size;
93 if (!cur->remaining)
94 return;
95
96 cur->size -= size;
97 if (cur->size) {
98 cur->start += size;
99 return;
100 }
101
102 cur->node = ++node;
103 cur->start = node->start << PAGE_SHIFT;
104 cur->size = min(node->size << PAGE_SHIFT, cur->remaining);
105 }
106
107 #endif
108