1 /*
2  * Copyright 2016 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Christian König
23  */
24 
25 #include <drm/drmP.h>
26 #include "amdgpu.h"
27 
28 struct amdgpu_vram_mgr {
29 	struct drm_mm mm;
30 	spinlock_t lock;
31 };
32 
33 /**
34  * amdgpu_vram_mgr_init - init VRAM manager and DRM MM
35  *
36  * @man: TTM memory type manager
37  * @p_size: maximum size of VRAM
38  *
39  * Allocate and initialize the VRAM manager.
40  */
41 static int amdgpu_vram_mgr_init(struct ttm_mem_type_manager *man,
42 				unsigned long p_size)
43 {
44 	struct amdgpu_vram_mgr *mgr;
45 
46 	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
47 	if (!mgr)
48 		return -ENOMEM;
49 
50 	drm_mm_init(&mgr->mm, 0, p_size);
51 	spin_lock_init(&mgr->lock);
52 	man->priv = mgr;
53 	return 0;
54 }
55 
56 /**
57  * amdgpu_vram_mgr_fini - free and destroy VRAM manager
58  *
59  * @man: TTM memory type manager
60  *
61  * Destroy and free the VRAM manager, returns -EBUSY if ranges are still
62  * allocated inside it.
63  */
64 static int amdgpu_vram_mgr_fini(struct ttm_mem_type_manager *man)
65 {
66 	struct amdgpu_vram_mgr *mgr = man->priv;
67 
68 	spin_lock(&mgr->lock);
69 	if (!drm_mm_clean(&mgr->mm)) {
70 		spin_unlock(&mgr->lock);
71 		return -EBUSY;
72 	}
73 
74 	drm_mm_takedown(&mgr->mm);
75 	spin_unlock(&mgr->lock);
76 	kfree(mgr);
77 	man->priv = NULL;
78 	return 0;
79 }
80 
81 /**
82  * amdgpu_vram_mgr_new - allocate new ranges
83  *
84  * @man: TTM memory type manager
85  * @tbo: TTM BO we need this range for
86  * @place: placement flags and restrictions
87  * @mem: the resulting mem object
88  *
89  * Allocate VRAM for the given BO.
90  */
91 static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
92 			       struct ttm_buffer_object *tbo,
93 			       const struct ttm_place *place,
94 			       struct ttm_mem_reg *mem)
95 {
96 	struct amdgpu_bo *bo = container_of(tbo, struct amdgpu_bo, tbo);
97 	struct amdgpu_vram_mgr *mgr = man->priv;
98 	struct drm_mm *mm = &mgr->mm;
99 	struct drm_mm_node *nodes;
100 	enum drm_mm_search_flags sflags = DRM_MM_SEARCH_DEFAULT;
101 	enum drm_mm_allocator_flags aflags = DRM_MM_CREATE_DEFAULT;
102 	unsigned long lpfn, num_nodes, pages_per_node, pages_left;
103 	unsigned i;
104 	int r;
105 
106 	lpfn = place->lpfn;
107 	if (!lpfn)
108 		lpfn = man->size;
109 
110 	if (bo->flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS ||
111 	    amdgpu_vram_page_split == -1) {
112 		pages_per_node = ~0ul;
113 		num_nodes = 1;
114 	} else {
115 		pages_per_node = max((uint32_t)amdgpu_vram_page_split,
116 				     mem->page_alignment);
117 		num_nodes = DIV_ROUND_UP(mem->num_pages, pages_per_node);
118 	}
119 
120 	nodes = kcalloc(num_nodes, sizeof(*nodes), GFP_KERNEL);
121 	if (!nodes)
122 		return -ENOMEM;
123 
124 	if (place->flags & TTM_PL_FLAG_TOPDOWN) {
125 		sflags = DRM_MM_SEARCH_BELOW;
126 		aflags = DRM_MM_CREATE_TOP;
127 	}
128 
129 	pages_left = mem->num_pages;
130 
131 	spin_lock(&mgr->lock);
132 	for (i = 0; i < num_nodes; ++i) {
133 		unsigned long pages = min(pages_left, pages_per_node);
134 		uint32_t alignment = mem->page_alignment;
135 
136 		if (pages == pages_per_node)
137 			alignment = pages_per_node;
138 		else
139 			sflags |= DRM_MM_SEARCH_BEST;
140 
141 		r = drm_mm_insert_node_in_range_generic(mm, &nodes[i], pages,
142 							alignment, 0,
143 							place->fpfn, lpfn,
144 							sflags, aflags);
145 		if (unlikely(r))
146 			goto error;
147 
148 		pages_left -= pages;
149 	}
150 	spin_unlock(&mgr->lock);
151 
152 	mem->start = num_nodes == 1 ? nodes[0].start : AMDGPU_BO_INVALID_OFFSET;
153 	mem->mm_node = nodes;
154 
155 	return 0;
156 
157 error:
158 	while (i--)
159 		drm_mm_remove_node(&nodes[i]);
160 	spin_unlock(&mgr->lock);
161 
162 	kfree(nodes);
163 	return r == -ENOSPC ? 0 : r;
164 }
165 
166 /**
167  * amdgpu_vram_mgr_del - free ranges
168  *
169  * @man: TTM memory type manager
170  * @tbo: TTM BO we need this range for
171  * @place: placement flags and restrictions
172  * @mem: TTM memory object
173  *
174  * Free the allocated VRAM again.
175  */
176 static void amdgpu_vram_mgr_del(struct ttm_mem_type_manager *man,
177 				struct ttm_mem_reg *mem)
178 {
179 	struct amdgpu_vram_mgr *mgr = man->priv;
180 	struct drm_mm_node *nodes = mem->mm_node;
181 	unsigned pages = mem->num_pages;
182 
183 	if (!mem->mm_node)
184 		return;
185 
186 	spin_lock(&mgr->lock);
187 	while (pages) {
188 		pages -= nodes->size;
189 		drm_mm_remove_node(nodes);
190 		++nodes;
191 	}
192 	spin_unlock(&mgr->lock);
193 
194 	kfree(mem->mm_node);
195 	mem->mm_node = NULL;
196 }
197 
198 /**
199  * amdgpu_vram_mgr_debug - dump VRAM table
200  *
201  * @man: TTM memory type manager
202  * @prefix: text prefix
203  *
204  * Dump the table content using printk.
205  */
206 static void amdgpu_vram_mgr_debug(struct ttm_mem_type_manager *man,
207 				  const char *prefix)
208 {
209 	struct amdgpu_vram_mgr *mgr = man->priv;
210 
211 	spin_lock(&mgr->lock);
212 	drm_mm_debug_table(&mgr->mm, prefix);
213 	spin_unlock(&mgr->lock);
214 }
215 
216 const struct ttm_mem_type_manager_func amdgpu_vram_mgr_func = {
217 	amdgpu_vram_mgr_init,
218 	amdgpu_vram_mgr_fini,
219 	amdgpu_vram_mgr_new,
220 	amdgpu_vram_mgr_del,
221 	amdgpu_vram_mgr_debug
222 };
223