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#include "amdgpu_vram_mgr.h"
34
35/* state back for walking over vram_mgr and gtt_mgr allocations */
36struct amdgpu_res_cursor {
37 uint64_t start;
38 uint64_t size;
39 uint64_t remaining;
40 void *node;
41 uint32_t mem_type;
42};
43
44/**
45 * amdgpu_res_first - initialize a amdgpu_res_cursor
46 *
47 * @res: TTM resource object to walk
48 * @start: Start of the range
49 * @size: Size of the range
50 * @cur: cursor object to initialize
51 *
52 * Start walking over the range of allocations between @start and @size.
53 */
54static inline void amdgpu_res_first(struct ttm_resource *res,
55 uint64_t start, uint64_t size,
56 struct amdgpu_res_cursor *cur)
57{
58 struct drm_buddy_block *block;
59 struct list_head *head, *next;
60 struct drm_mm_node *node;
61
62 if (!res)
63 goto fallback;
64
65 BUG_ON(start + size > res->size);
66
67 cur->mem_type = res->mem_type;
68
69 switch (cur->mem_type) {
70 case TTM_PL_VRAM:
71 head = &to_amdgpu_vram_mgr_resource(res)->blocks;
72
73 block = list_first_entry_or_null(head,
74 struct drm_buddy_block,
75 link);
76 if (!block)
77 goto fallback;
78
79 while (start >= amdgpu_vram_mgr_block_size(block)) {
80 start -= amdgpu_vram_mgr_block_size(block);
81
82 next = block->link.next;
83 if (next != head)
84 block = list_entry(next, struct drm_buddy_block, link);
85 }
86
87 cur->start = amdgpu_vram_mgr_block_start(block) + start;
88 cur->size = min(amdgpu_vram_mgr_block_size(block) - start, size);
89 cur->remaining = size;
90 cur->node = block;
91 break;
92 case TTM_PL_TT:
93 case AMDGPU_PL_DOORBELL:
94 node = to_ttm_range_mgr_node(res)->mm_nodes;
95 while (start >= node->size << PAGE_SHIFT)
96 start -= node++->size << PAGE_SHIFT;
97
98 cur->start = (node->start << PAGE_SHIFT) + start;
99 cur->size = min((node->size << PAGE_SHIFT) - start, size);
100 cur->remaining = size;
101 cur->node = node;
102 break;
103 default:
104 goto fallback;
105 }
106
107 return;
108
109fallback:
110 cur->start = start;
111 cur->size = size;
112 cur->remaining = size;
113 cur->node = NULL;
114 WARN_ON(res && start + size > res->size);
115}
116
117/**
118 * amdgpu_res_next - advance the cursor
119 *
120 * @cur: the cursor to advance
121 * @size: number of bytes to move forward
122 *
123 * Move the cursor @size bytes forwrad, walking to the next node if necessary.
124 */
125static inline void amdgpu_res_next(struct amdgpu_res_cursor *cur, uint64_t size)
126{
127 struct drm_buddy_block *block;
128 struct drm_mm_node *node;
129 struct list_head *next;
130
131 BUG_ON(size > cur->remaining);
132
133 cur->remaining -= size;
134 if (!cur->remaining)
135 return;
136
137 cur->size -= size;
138 if (cur->size) {
139 cur->start += size;
140 return;
141 }
142
143 switch (cur->mem_type) {
144 case TTM_PL_VRAM:
145 block = cur->node;
146
147 next = block->link.next;
148 block = list_entry(next, struct drm_buddy_block, link);
149
150 cur->node = block;
151 cur->start = amdgpu_vram_mgr_block_start(block);
152 cur->size = min(amdgpu_vram_mgr_block_size(block), cur->remaining);
153 break;
154 case TTM_PL_TT:
155 case AMDGPU_PL_DOORBELL:
156 node = cur->node;
157
158 cur->node = ++node;
159 cur->start = node->start << PAGE_SHIFT;
160 cur->size = min(node->size << PAGE_SHIFT, cur->remaining);
161 break;
162 default:
163 return;
164 }
165}
166
167#endif
168

source code of linux/drivers/gpu/drm/amd/amdgpu/amdgpu_res_cursor.h