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
48 static const struct agp_version agp_current_version =
49 {
50 .major = AGPGART_VERSION_MAJOR,
51 .minor = AGPGART_VERSION_MINOR,
52 };
53
54 struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) =
55 &agp_generic_find_bridge;
56
57 struct agp_bridge_data *agp_bridge;
58 LIST_HEAD(agp_bridges);
59 EXPORT_SYMBOL(agp_bridge);
60 EXPORT_SYMBOL(agp_bridges);
61 EXPORT_SYMBOL(agp_find_bridge);
62
63 /**
64 * agp_backend_acquire - attempt to acquire an agp backend.
65 *
66 */
agp_backend_acquire(struct pci_dev * pdev)67 struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev)
68 {
69 struct agp_bridge_data *bridge;
70
71 bridge = agp_find_bridge(pdev);
72
73 if (!bridge)
74 return NULL;
75
76 if (atomic_read(&bridge->agp_in_use))
77 return NULL;
78 atomic_inc(&bridge->agp_in_use);
79 return bridge;
80 }
81 EXPORT_SYMBOL(agp_backend_acquire);
82
83
84 /**
85 * agp_backend_release - release the lock on the agp backend.
86 *
87 * The caller must insure that the graphics aperture translation table
88 * is read for use by another entity.
89 *
90 * (Ensure that all memory it bound is unbound.)
91 */
agp_backend_release(struct agp_bridge_data * bridge)92 void agp_backend_release(struct agp_bridge_data *bridge)
93 {
94
95 if (bridge)
96 atomic_dec(&bridge->agp_in_use);
97 }
98 EXPORT_SYMBOL(agp_backend_release);
99
100
101 static const struct { int mem, agp; } maxes_table[] = {
102 {0, 0},
103 {32, 4},
104 {64, 28},
105 {128, 96},
106 {256, 204},
107 {512, 440},
108 {1024, 942},
109 {2048, 1920},
110 {4096, 3932}
111 };
112
agp_find_max(void)113 static int agp_find_max(void)
114 {
115 long memory, index, result;
116
117 #if PAGE_SHIFT < 20
118 memory = totalram_pages >> (20 - PAGE_SHIFT);
119 #else
120 memory = totalram_pages << (PAGE_SHIFT - 20);
121 #endif
122 index = 1;
123
124 while ((memory > maxes_table[index].mem) && (index < 8))
125 index++;
126
127 result = maxes_table[index - 1].agp +
128 ( (memory - maxes_table[index - 1].mem) *
129 (maxes_table[index].agp - maxes_table[index - 1].agp)) /
130 (maxes_table[index].mem - maxes_table[index - 1].mem);
131
132 result = result << (20 - PAGE_SHIFT);
133 return result;
134 }
135
136
agp_backend_initialize(struct agp_bridge_data * bridge)137 static int agp_backend_initialize(struct agp_bridge_data *bridge)
138 {
139 int size_value, rc, got_gatt=0, got_keylist=0;
140
141 bridge->max_memory_agp = agp_find_max();
142 bridge->version = &agp_current_version;
143
144 if (bridge->driver->needs_scratch_page) {
145 struct page *page = bridge->driver->agp_alloc_page(bridge);
146
147 if (!page) {
148 dev_err(&bridge->dev->dev,
149 "can't get memory for scratch page\n");
150 return -ENOMEM;
151 }
152
153 bridge->scratch_page_page = page;
154 bridge->scratch_page_dma = page_to_phys(page);
155
156 bridge->scratch_page = bridge->driver->mask_memory(bridge,
157 bridge->scratch_page_dma, 0);
158 }
159
160 size_value = bridge->driver->fetch_size();
161 if (size_value == 0) {
162 dev_err(&bridge->dev->dev, "can't determine aperture size\n");
163 rc = -EINVAL;
164 goto err_out;
165 }
166 if (bridge->driver->create_gatt_table(bridge)) {
167 dev_err(&bridge->dev->dev,
168 "can't get memory for graphics translation table\n");
169 rc = -ENOMEM;
170 goto err_out;
171 }
172 got_gatt = 1;
173
174 bridge->key_list = vzalloc(PAGE_SIZE * 4);
175 if (bridge->key_list == NULL) {
176 dev_err(&bridge->dev->dev,
177 "can't allocate memory for key lists\n");
178 rc = -ENOMEM;
179 goto err_out;
180 }
181 got_keylist = 1;
182
183 /* FIXME vmalloc'd memory not guaranteed contiguous */
184
185 if (bridge->driver->configure()) {
186 dev_err(&bridge->dev->dev, "error configuring host chipset\n");
187 rc = -EINVAL;
188 goto err_out;
189 }
190 INIT_LIST_HEAD(&bridge->mapped_list);
191 spin_lock_init(&bridge->mapped_lock);
192
193 return 0;
194
195 err_out:
196 if (bridge->driver->needs_scratch_page) {
197 struct page *page = bridge->scratch_page_page;
198
199 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
200 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
201 }
202 if (got_gatt)
203 bridge->driver->free_gatt_table(bridge);
204 if (got_keylist) {
205 vfree(bridge->key_list);
206 bridge->key_list = NULL;
207 }
208 return rc;
209 }
210
211 /* cannot be __exit b/c as it could be called from __init code */
agp_backend_cleanup(struct agp_bridge_data * bridge)212 static void agp_backend_cleanup(struct agp_bridge_data *bridge)
213 {
214 if (bridge->driver->cleanup)
215 bridge->driver->cleanup();
216 if (bridge->driver->free_gatt_table)
217 bridge->driver->free_gatt_table(bridge);
218
219 vfree(bridge->key_list);
220 bridge->key_list = NULL;
221
222 if (bridge->driver->agp_destroy_page &&
223 bridge->driver->needs_scratch_page) {
224 struct page *page = bridge->scratch_page_page;
225
226 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_UNMAP);
227 bridge->driver->agp_destroy_page(page, AGP_PAGE_DESTROY_FREE);
228 }
229 }
230
231 /* When we remove the global variable agp_bridge from all drivers
232 * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
233 */
234
agp_alloc_bridge(void)235 struct agp_bridge_data *agp_alloc_bridge(void)
236 {
237 struct agp_bridge_data *bridge;
238
239 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
240 if (!bridge)
241 return NULL;
242
243 atomic_set(&bridge->agp_in_use, 0);
244 atomic_set(&bridge->current_memory_agp, 0);
245
246 if (list_empty(&agp_bridges))
247 agp_bridge = bridge;
248
249 return bridge;
250 }
251 EXPORT_SYMBOL(agp_alloc_bridge);
252
253
agp_put_bridge(struct agp_bridge_data * bridge)254 void agp_put_bridge(struct agp_bridge_data *bridge)
255 {
256 kfree(bridge);
257
258 if (list_empty(&agp_bridges))
259 agp_bridge = NULL;
260 }
261 EXPORT_SYMBOL(agp_put_bridge);
262
263
agp_add_bridge(struct agp_bridge_data * bridge)264 int agp_add_bridge(struct agp_bridge_data *bridge)
265 {
266 int error;
267
268 if (agp_off) {
269 error = -ENODEV;
270 goto err_put_bridge;
271 }
272
273 if (!bridge->dev) {
274 printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");
275 error = -EINVAL;
276 goto err_put_bridge;
277 }
278
279 /* Grab reference on the chipset driver. */
280 if (!try_module_get(bridge->driver->owner)) {
281 dev_info(&bridge->dev->dev, "can't lock chipset driver\n");
282 error = -EINVAL;
283 goto err_put_bridge;
284 }
285
286 error = agp_backend_initialize(bridge);
287 if (error) {
288 dev_info(&bridge->dev->dev,
289 "agp_backend_initialize() failed\n");
290 goto err_out;
291 }
292
293 if (list_empty(&agp_bridges)) {
294 error = agp_frontend_initialize();
295 if (error) {
296 dev_info(&bridge->dev->dev,
297 "agp_frontend_initialize() failed\n");
298 goto frontend_err;
299 }
300
301 dev_info(&bridge->dev->dev, "AGP aperture is %dM @ 0x%lx\n",
302 bridge->driver->fetch_size(), bridge->gart_bus_addr);
303
304 }
305
306 list_add(&bridge->list, &agp_bridges);
307 return 0;
308
309 frontend_err:
310 agp_backend_cleanup(bridge);
311 err_out:
312 module_put(bridge->driver->owner);
313 err_put_bridge:
314 agp_put_bridge(bridge);
315 return error;
316 }
317 EXPORT_SYMBOL_GPL(agp_add_bridge);
318
319
agp_remove_bridge(struct agp_bridge_data * bridge)320 void agp_remove_bridge(struct agp_bridge_data *bridge)
321 {
322 agp_backend_cleanup(bridge);
323 list_del(&bridge->list);
324 if (list_empty(&agp_bridges))
325 agp_frontend_cleanup();
326 module_put(bridge->driver->owner);
327 }
328 EXPORT_SYMBOL_GPL(agp_remove_bridge);
329
330 int agp_off;
331 int agp_try_unsupported_boot;
332 EXPORT_SYMBOL(agp_off);
333 EXPORT_SYMBOL(agp_try_unsupported_boot);
334
agp_init(void)335 static int __init agp_init(void)
336 {
337 if (!agp_off)
338 printk(KERN_INFO "Linux agpgart interface v%d.%d\n",
339 AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
340 return 0;
341 }
342
agp_exit(void)343 static void __exit agp_exit(void)
344 {
345 }
346
347 #ifndef MODULE
agp_setup(char * s)348 static __init int agp_setup(char *s)
349 {
350 if (!strcmp(s,"off"))
351 agp_off = 1;
352 if (!strcmp(s,"try_unsupported"))
353 agp_try_unsupported_boot = 1;
354 return 1;
355 }
356 __setup("agp=", agp_setup);
357 #endif
358
359 MODULE_AUTHOR("Dave Jones, Jeff Hartmann");
360 MODULE_DESCRIPTION("AGP GART driver");
361 MODULE_LICENSE("GPL and additional rights");
362 MODULE_ALIAS_MISCDEV(AGPGART_MINOR);
363
364 module_init(agp_init);
365 module_exit(agp_exit);
366
367