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_device.h>
36#include <drm/ttm/ttm_tt.h>
37#include <drm/ttm/ttm_resource.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
44struct ttm_agp_backend {
45 struct ttm_tt ttm;
46 struct agp_memory *mem;
47 struct agp_bridge_data *bridge;
48};
49
50int 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_glob.dummy_read_page;
54 struct agp_memory *mem;
55 int ret, cached = ttm->caching == ttm_cached;
56 unsigned i;
57
58 if (agp_be->mem)
59 return 0;
60
61 mem = agp_allocate_memory(agp_be->bridge, ttm->num_pages, AGP_USER_MEMORY);
62 if (unlikely(mem == NULL))
63 return -ENOMEM;
64
65 mem->page_count = 0;
66 for (i = 0; i < ttm->num_pages; i++) {
67 struct page *page = ttm->pages[i];
68
69 if (!page)
70 page = dummy_read_page;
71
72 mem->pages[mem->page_count++] = page;
73 }
74 agp_be->mem = mem;
75
76 mem->is_flushed = 1;
77 mem->type = (cached) ? AGP_USER_CACHED_MEMORY : AGP_USER_MEMORY;
78
79 ret = agp_bind_memory(mem, bo_mem->start);
80 if (ret)
81 pr_err("AGP Bind memory failed\n");
82
83 return ret;
84}
85EXPORT_SYMBOL(ttm_agp_bind);
86
87void ttm_agp_unbind(struct ttm_tt *ttm)
88{
89 struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
90
91 if (agp_be->mem) {
92 if (agp_be->mem->is_bound) {
93 agp_unbind_memory(agp_be->mem);
94 return;
95 }
96 agp_free_memory(agp_be->mem);
97 agp_be->mem = NULL;
98 }
99}
100EXPORT_SYMBOL(ttm_agp_unbind);
101
102bool ttm_agp_is_bound(struct ttm_tt *ttm)
103{
104 struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
105
106 if (!ttm)
107 return false;
108
109 return (agp_be->mem != NULL);
110}
111EXPORT_SYMBOL(ttm_agp_is_bound);
112
113void ttm_agp_destroy(struct ttm_tt *ttm)
114{
115 struct ttm_agp_backend *agp_be = container_of(ttm, struct ttm_agp_backend, ttm);
116
117 if (agp_be->mem)
118 ttm_agp_unbind(ttm);
119 ttm_tt_fini(ttm);
120 kfree(objp: agp_be);
121}
122EXPORT_SYMBOL(ttm_agp_destroy);
123
124struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
125 struct agp_bridge_data *bridge,
126 uint32_t page_flags)
127{
128 struct ttm_agp_backend *agp_be;
129
130 agp_be = kmalloc(size: sizeof(*agp_be), GFP_KERNEL);
131 if (!agp_be)
132 return NULL;
133
134 agp_be->mem = NULL;
135 agp_be->bridge = bridge;
136
137 if (ttm_tt_init(ttm: &agp_be->ttm, bo, page_flags, caching: ttm_write_combined, extra_pages: 0)) {
138 kfree(objp: agp_be);
139 return NULL;
140 }
141
142 return &agp_be->ttm;
143}
144EXPORT_SYMBOL(ttm_agp_tt_create);
145

source code of linux/drivers/gpu/drm/ttm/ttm_agp_backend.c