1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 /**************************************************************************
3  *
4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sub license, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the
16  * next paragraph) shall be included in all copies or substantial portions
17  * of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25  * USE OR OTHER DEALINGS IN THE SOFTWARE.
26  *
27  **************************************************************************/
28 /*
29  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30  *          Keith Packard.
31  */
32 
33 #define pr_fmt(fmt) "[TTM] " fmt
34 
35 #include <drm/ttm/ttm_module.h>
36 #include <drm/ttm/ttm_bo_driver.h>
37 #include <drm/ttm/ttm_placement.h>
38 #include <linux/agp_backend.h>
39 #include <linux/module.h>
40 #include <linux/slab.h>
41 #include <linux/io.h>
42 #include <asm/agp.h>
43 
44 struct ttm_agp_backend {
45 	struct ttm_tt ttm;
46 	struct agp_memory *mem;
47 	struct agp_bridge_data *bridge;
48 };
49 
50 int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_resource *bo_mem)
51 {
52 	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
53 	struct page *dummy_read_page = ttm_bo_glob.dummy_read_page;
54 	struct drm_mm_node *node = bo_mem->mm_node;
55 	struct agp_memory *mem;
56 	int ret, cached = ttm->caching == ttm_cached;
57 	unsigned i;
58 
59 	if (agp_be->mem)
60 		return 0;
61 
62 	mem = agp_allocate_memory(agp_be->bridge, ttm->num_pages, AGP_USER_MEMORY);
63 	if (unlikely(mem == NULL))
64 		return -ENOMEM;
65 
66 	mem->page_count = 0;
67 	for (i = 0; i < ttm->num_pages; i++) {
68 		struct page *page = ttm->pages[i];
69 
70 		if (!page)
71 			page = dummy_read_page;
72 
73 		mem->pages[mem->page_count++] = page;
74 	}
75 	agp_be->mem = mem;
76 
77 	mem->is_flushed = 1;
78 	mem->type = (cached) ? AGP_USER_CACHED_MEMORY : AGP_USER_MEMORY;
79 
80 	ret = agp_bind_memory(mem, node->start);
81 	if (ret)
82 		pr_err("AGP Bind memory failed\n");
83 
84 	return ret;
85 }
86 EXPORT_SYMBOL(ttm_agp_bind);
87 
88 void ttm_agp_unbind(struct ttm_tt *ttm)
89 {
90 	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
91 
92 	if (agp_be->mem) {
93 		if (agp_be->mem->is_bound) {
94 			agp_unbind_memory(agp_be->mem);
95 			return;
96 		}
97 		agp_free_memory(agp_be->mem);
98 		agp_be->mem = NULL;
99 	}
100 }
101 EXPORT_SYMBOL(ttm_agp_unbind);
102 
103 bool ttm_agp_is_bound(struct ttm_tt *ttm)
104 {
105 	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
106 
107 	if (!ttm)
108 		return false;
109 
110 	return (agp_be->mem != NULL);
111 }
112 EXPORT_SYMBOL(ttm_agp_is_bound);
113 
114 void ttm_agp_destroy(struct ttm_tt *ttm)
115 {
116 	struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
117 
118 	if (agp_be->mem)
119 		ttm_agp_unbind(ttm);
120 	ttm_tt_fini(ttm);
121 	kfree(agp_be);
122 }
123 EXPORT_SYMBOL(ttm_agp_destroy);
124 
125 struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
126 				 struct agp_bridge_data *bridge,
127 				 uint32_t page_flags)
128 {
129 	struct ttm_agp_backend *agp_be;
130 
131 	agp_be = kmalloc(sizeof(*agp_be), GFP_KERNEL);
132 	if (!agp_be)
133 		return NULL;
134 
135 	agp_be->mem = NULL;
136 	agp_be->bridge = bridge;
137 
138 	if (ttm_tt_init(&agp_be->ttm, bo, page_flags, ttm_write_combined)) {
139 		kfree(agp_be);
140 		return NULL;
141 	}
142 
143 	return &agp_be->ttm;
144 }
145 EXPORT_SYMBOL(ttm_agp_tt_create);
146