1/*
2 * AGPGART driver backend routines.
3 * Copyright (C) 2004 Silicon Graphics, Inc.
4 * Copyright (C) 2002-2003 Dave Jones.
5 * Copyright (C) 1999 Jeff Hartmann.
6 * Copyright (C) 1999 Precision Insight, Inc.
7 * Copyright (C) 1999 Xi Graphics, Inc.
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the "Software"),
11 * to deal in the Software without restriction, including without limitation
12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13 * and/or sell copies of the Software, and to permit persons to whom the
14 * Software is furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice shall be included
17 * in all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22 * JEFF HARTMANN, DAVE JONES, OR ANY OTHER CONTRIBUTORS 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
25 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 * TODO:
28 * - Allocate more than order 0 pages to avoid too much linear map splitting.
29 */
30#include <linux/module.h>
31#include <linux/pci.h>
32#include <linux/init.h>
33#include <linux/slab.h>
34#include <linux/pagemap.h>
35#include <linux/miscdevice.h>
36#include <linux/pm.h>
37#include <linux/agp_backend.h>
38#include <linux/agpgart.h>
39#include <linux/vmalloc.h>
40#include <asm/io.h>
41#include "agp.h"
42
43/* Due to XFree86 brain-damage, we can't go to 1.0 until they
44 * fix some real stupidity. It's only by chance we can bump
45 * past 0.99 at all due to some boolean logic error. */
46#define AGPGART_VERSION_MAJOR 0
47#define AGPGART_VERSION_MINOR 103
48static const struct agp_version agp_current_version =
49{
50 .major = AGPGART_VERSION_MAJOR,
51 .minor = AGPGART_VERSION_MINOR,
52};
53
54struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) =
55 &agp_generic_find_bridge;
56
57struct agp_bridge_data *agp_bridge;
58LIST_HEAD(agp_bridges);
59EXPORT_SYMBOL(agp_bridge);
60EXPORT_SYMBOL(agp_bridges);
61EXPORT_SYMBOL(agp_find_bridge);
62
63/**
64 * agp_backend_acquire - attempt to acquire an agp backend.
65 * @pdev: the PCI device
66 *
67 */
68struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev)
69{
70 struct agp_bridge_data *bridge;
71
72 bridge = agp_find_bridge(pdev);
73
74 if (!bridge)
75 return NULL;
76
77 if (atomic_read(v: &bridge->agp_in_use))
78 return NULL;
79 atomic_inc(v: &bridge->agp_in_use);
80 return bridge;
81}
82EXPORT_SYMBOL(agp_backend_acquire);
83
84
85/**
86 * agp_backend_release - release the lock on the agp backend.
87 * @bridge: the AGP backend to release
88 *
89 * The caller must insure that the graphics aperture translation table
90 * is read for use by another entity.
91 *
92 * (Ensure that all memory it bound is unbound.)
93 */
94void agp_backend_release(struct agp_bridge_data *bridge)
95{
96
97 if (bridge)
98 atomic_dec(v: &bridge->agp_in_use);
99}
100EXPORT_SYMBOL(agp_backend_release);
101
102
103static const struct { int mem, agp; } maxes_table[] = {
104 {0, 0},
105 {.mem: 32, .agp: 4},
106 {.mem: 64, .agp: 28},
107 {.mem: 128, .agp: 96},
108 {.mem: 256, .agp: 204},
109 {.mem: 512, .agp: 440},
110 {.mem: 1024, .agp: 942},
111 {.mem: 2048, .agp: 1920},
112 {.mem: 4096, .agp: 3932}
113};
114
115static int agp_find_max(void)
116{
117 long memory, index, result;
118
119#if PAGE_SHIFT < 20
120 memory = totalram_pages() >> (20 - PAGE_SHIFT);
121#else
122 memory = totalram_pages() << (PAGE_SHIFT - 20);
123#endif
124 index = 1;
125
126 while ((memory > maxes_table[index].mem) && (index < 8))
127 index++;
128
129 result = maxes_table[index - 1].agp +
130 ( (memory - maxes_table[index - 1].mem) *
131 (maxes_table[index].agp - maxes_table[index - 1].agp)) /
132 (maxes_table[index].mem - maxes_table[index - 1].mem);
133
134 result = result << (20 - PAGE_SHIFT);
135 return result;
136}
137
138
139static int agp_backend_initialize(struct agp_bridge_data *bridge)
140{
141 int size_value, rc, got_gatt=0, got_keylist=0;
142
143 bridge->max_memory_agp = agp_find_max();
144 bridge->version = &agp_current_version;
145
146 if (bridge->driver->needs_scratch_page) {
147 struct page *page = bridge->driver->agp_alloc_page(bridge);
148
149 if (!page) {
150 dev_err(&bridge->dev->dev,
151 "can't get memory for scratch page\n");
152 return -ENOMEM;
153 }
154
155 bridge->scratch_page_page = page;
156 bridge->scratch_page_dma = page_to_phys(page);
157
158 bridge->scratch_page = bridge->driver->mask_memory(bridge,
159 bridge->scratch_page_dma, 0);
160 }
161
162 size_value = bridge->driver->fetch_size();
163 if (size_value == 0) {
164 dev_err(&bridge->dev->dev, "can't determine aperture size\n");
165 rc = -EINVAL;
166 goto err_out;
167 }
168 if (bridge->driver->create_gatt_table(bridge)) {
169 dev_err(&bridge->dev->dev,
170 "can't get memory for graphics translation table\n");
171 rc = -ENOMEM;
172 goto err_out;
173 }
174 got_gatt = 1;
175
176 bridge->key_list = vzalloc(PAGE_SIZE * 4);
177 if (bridge->key_list == NULL) {
178 dev_err(&bridge->dev->dev,
179 "can't allocate memory for key lists\n");
180 rc = -ENOMEM;
181 goto err_out;
182 }
183 got_keylist = 1;
184
185 /* FIXME vmalloc'd memory not guaranteed contiguous */
186
187 if (bridge->driver->configure()) {
188 dev_err(&bridge->dev->dev, "error configuring host chipset\n");
189 rc = -EINVAL;
190 goto err_out;
191 }
192 INIT_LIST_HEAD(list: &bridge->mapped_list);
193 spin_lock_init(&bridge->mapped_lock);
194
195 return 0;
196
197err_out:
198 if (bridge->driver->needs_scratch_page) {
199 struct page *page = bridge->scratch_page_page;
200
201 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
202 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
203 }
204 if (got_gatt)
205 bridge->driver->free_gatt_table(bridge);
206 if (got_keylist) {
207 vfree(addr: bridge->key_list);
208 bridge->key_list = NULL;
209 }
210 return rc;
211}
212
213/* cannot be __exit b/c as it could be called from __init code */
214static void agp_backend_cleanup(struct agp_bridge_data *bridge)
215{
216 if (bridge->driver->cleanup)
217 bridge->driver->cleanup();
218 if (bridge->driver->free_gatt_table)
219 bridge->driver->free_gatt_table(bridge);
220
221 vfree(addr: bridge->key_list);
222 bridge->key_list = NULL;
223
224 if (bridge->driver->agp_destroy_page &&
225 bridge->driver->needs_scratch_page) {
226 struct page *page = bridge->scratch_page_page;
227
228 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
229 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
230 }
231}
232
233/* When we remove the global variable agp_bridge from all drivers
234 * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
235 */
236
237struct agp_bridge_data *agp_alloc_bridge(void)
238{
239 struct agp_bridge_data *bridge;
240
241 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
242 if (!bridge)
243 return NULL;
244
245 atomic_set(v: &bridge->agp_in_use, i: 0);
246 atomic_set(v: &bridge->current_memory_agp, i: 0);
247
248 if (list_empty(head: &agp_bridges))
249 agp_bridge = bridge;
250
251 return bridge;
252}
253EXPORT_SYMBOL(agp_alloc_bridge);
254
255
256void agp_put_bridge(struct agp_bridge_data *bridge)
257{
258 kfree(objp: bridge);
259
260 if (list_empty(head: &agp_bridges))
261 agp_bridge = NULL;
262}
263EXPORT_SYMBOL(agp_put_bridge);
264
265
266int agp_add_bridge(struct agp_bridge_data *bridge)
267{
268 int error;
269
270 if (agp_off) {
271 error = -ENODEV;
272 goto err_put_bridge;
273 }
274
275 if (!bridge->dev) {
276 printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
277 error = -EINVAL;
278 goto err_put_bridge;
279 }
280
281 /* Grab reference on the chipset driver. */
282 if (!try_module_get(module: bridge->driver->owner)) {
283 dev_info(&bridge->dev->dev, "can't lock chipset driver\n");
284 error = -EINVAL;
285 goto err_put_bridge;
286 }
287
288 error = agp_backend_initialize(bridge);
289 if (error) {
290 dev_info(&bridge->dev->dev,
291 "agp_backend_initialize() failed\n");
292 goto err_out;
293 }
294
295 if (list_empty(head: &agp_bridges)) {
296 dev_info(&bridge->dev->dev, "AGP aperture is %dM @ 0x%lx\n",
297 bridge->driver->fetch_size(), bridge->gart_bus_addr);
298
299 }
300
301 list_add(new: &bridge->list, head: &agp_bridges);
302 return 0;
303
304err_out:
305 module_put(module: bridge->driver->owner);
306err_put_bridge:
307 agp_put_bridge(bridge);
308 return error;
309}
310EXPORT_SYMBOL_GPL(agp_add_bridge);
311
312
313void agp_remove_bridge(struct agp_bridge_data *bridge)
314{
315 agp_backend_cleanup(bridge);
316 list_del(entry: &bridge->list);
317 module_put(module: bridge->driver->owner);
318}
319EXPORT_SYMBOL_GPL(agp_remove_bridge);
320
321int agp_off;
322int agp_try_unsupported_boot;
323EXPORT_SYMBOL(agp_off);
324EXPORT_SYMBOL(agp_try_unsupported_boot);
325
326static int __init agp_init(void)
327{
328 if (!agp_off)
329 printk(KERN_INFO "Linux agpgart interface v%d.%d\n",
330 AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
331 return 0;
332}
333
334static void __exit agp_exit(void)
335{
336}
337
338#ifndef MODULE
339static __init int agp_setup(char *s)
340{
341 if (!strcmp(s,"off"))
342 agp_off = 1;
343 if (!strcmp(s,"try_unsupported"))
344 agp_try_unsupported_boot = 1;
345 return 1;
346}
347__setup("agp=", agp_setup);
348#endif
349
350MODULE_AUTHOR("Dave Jones, Jeff Hartmann");
351MODULE_DESCRIPTION("AGP GART driver");
352MODULE_LICENSE("GPL and additional rights");
353MODULE_ALIAS_MISCDEV(AGPGART_MINOR);
354
355module_init(agp_init);
356module_exit(agp_exit);
357
358