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/pagemap.h> 34 #include <linux/miscdevice.h> 35 #include <linux/pm.h> 36 #include <linux/agp_backend.h> 37 #include <linux/agpgart.h> 38 #include <linux/vmalloc.h> 39 #include <asm/io.h> 40 #include "agp.h" 41 42 /* Due to XFree86 brain-damage, we can't go to 1.0 until they 43 * fix some real stupidity. It's only by chance we can bump 44 * past 0.99 at all due to some boolean logic error. */ 45 #define AGPGART_VERSION_MAJOR 0 46 #define AGPGART_VERSION_MINOR 102 47 static const struct agp_version agp_current_version = 48 { 49 .major = AGPGART_VERSION_MAJOR, 50 .minor = AGPGART_VERSION_MINOR, 51 }; 52 53 struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) = 54 &agp_generic_find_bridge; 55 56 struct agp_bridge_data *agp_bridge; 57 LIST_HEAD(agp_bridges); 58 EXPORT_SYMBOL(agp_bridge); 59 EXPORT_SYMBOL(agp_bridges); 60 EXPORT_SYMBOL(agp_find_bridge); 61 62 /** 63 * agp_backend_acquire - attempt to acquire an agp backend. 64 * 65 */ 66 struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev) 67 { 68 struct agp_bridge_data *bridge; 69 70 bridge = agp_find_bridge(pdev); 71 72 if (!bridge) 73 return NULL; 74 75 if (atomic_read(&bridge->agp_in_use)) 76 return NULL; 77 atomic_inc(&bridge->agp_in_use); 78 return bridge; 79 } 80 EXPORT_SYMBOL(agp_backend_acquire); 81 82 83 /** 84 * agp_backend_release - release the lock on the agp backend. 85 * 86 * The caller must insure that the graphics aperture translation table 87 * is read for use by another entity. 88 * 89 * (Ensure that all memory it bound is unbound.) 90 */ 91 void agp_backend_release(struct agp_bridge_data *bridge) 92 { 93 94 if (bridge) 95 atomic_dec(&bridge->agp_in_use); 96 } 97 EXPORT_SYMBOL(agp_backend_release); 98 99 100 static const struct { int mem, agp; } maxes_table[] = { 101 {0, 0}, 102 {32, 4}, 103 {64, 28}, 104 {128, 96}, 105 {256, 204}, 106 {512, 440}, 107 {1024, 942}, 108 {2048, 1920}, 109 {4096, 3932} 110 }; 111 112 static int agp_find_max(void) 113 { 114 long memory, index, result; 115 116 #if PAGE_SHIFT < 20 117 memory = num_physpages >> (20 - PAGE_SHIFT); 118 #else 119 memory = num_physpages << (PAGE_SHIFT - 20); 120 #endif 121 index = 1; 122 123 while ((memory > maxes_table[index].mem) && (index < 8)) 124 index++; 125 126 result = maxes_table[index - 1].agp + 127 ( (memory - maxes_table[index - 1].mem) * 128 (maxes_table[index].agp - maxes_table[index - 1].agp)) / 129 (maxes_table[index].mem - maxes_table[index - 1].mem); 130 131 result = result << (20 - PAGE_SHIFT); 132 return result; 133 } 134 135 136 static int agp_backend_initialize(struct agp_bridge_data *bridge) 137 { 138 int size_value, rc, got_gatt=0, got_keylist=0; 139 140 bridge->max_memory_agp = agp_find_max(); 141 bridge->version = &agp_current_version; 142 143 if (bridge->driver->needs_scratch_page) { 144 void *addr = bridge->driver->agp_alloc_page(bridge); 145 146 if (!addr) { 147 printk(KERN_ERR PFX "unable to get memory for scratch page.\n"); 148 return -ENOMEM; 149 } 150 flush_agp_mappings(); 151 152 bridge->scratch_page_real = virt_to_gart(addr); 153 bridge->scratch_page = 154 bridge->driver->mask_memory(bridge, bridge->scratch_page_real, 0); 155 } 156 157 size_value = bridge->driver->fetch_size(); 158 if (size_value == 0) { 159 printk(KERN_ERR PFX "unable to determine aperture size.\n"); 160 rc = -EINVAL; 161 goto err_out; 162 } 163 if (bridge->driver->create_gatt_table(bridge)) { 164 printk(KERN_ERR PFX 165 "unable to get memory for graphics translation table.\n"); 166 rc = -ENOMEM; 167 goto err_out; 168 } 169 got_gatt = 1; 170 171 bridge->key_list = vmalloc(PAGE_SIZE * 4); 172 if (bridge->key_list == NULL) { 173 printk(KERN_ERR PFX "error allocating memory for key lists.\n"); 174 rc = -ENOMEM; 175 goto err_out; 176 } 177 got_keylist = 1; 178 179 /* FIXME vmalloc'd memory not guaranteed contiguous */ 180 memset(bridge->key_list, 0, PAGE_SIZE * 4); 181 182 if (bridge->driver->configure()) { 183 printk(KERN_ERR PFX "error configuring host chipset.\n"); 184 rc = -EINVAL; 185 goto err_out; 186 } 187 188 return 0; 189 190 err_out: 191 if (bridge->driver->needs_scratch_page) { 192 bridge->driver->agp_destroy_page( 193 gart_to_virt(bridge->scratch_page_real)); 194 flush_agp_mappings(); 195 } 196 if (got_gatt) 197 bridge->driver->free_gatt_table(bridge); 198 if (got_keylist) { 199 vfree(bridge->key_list); 200 bridge->key_list = NULL; 201 } 202 return rc; 203 } 204 205 /* cannot be __exit b/c as it could be called from __init code */ 206 static void agp_backend_cleanup(struct agp_bridge_data *bridge) 207 { 208 if (bridge->driver->cleanup) 209 bridge->driver->cleanup(); 210 if (bridge->driver->free_gatt_table) 211 bridge->driver->free_gatt_table(bridge); 212 213 vfree(bridge->key_list); 214 bridge->key_list = NULL; 215 216 if (bridge->driver->agp_destroy_page && 217 bridge->driver->needs_scratch_page) { 218 bridge->driver->agp_destroy_page( 219 gart_to_virt(bridge->scratch_page_real)); 220 flush_agp_mappings(); 221 } 222 } 223 224 /* When we remove the global variable agp_bridge from all drivers 225 * then agp_alloc_bridge and agp_generic_find_bridge need to be updated 226 */ 227 228 struct agp_bridge_data *agp_alloc_bridge(void) 229 { 230 struct agp_bridge_data *bridge; 231 232 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL); 233 if (!bridge) 234 return NULL; 235 236 atomic_set(&bridge->agp_in_use, 0); 237 atomic_set(&bridge->current_memory_agp, 0); 238 239 if (list_empty(&agp_bridges)) 240 agp_bridge = bridge; 241 242 return bridge; 243 } 244 EXPORT_SYMBOL(agp_alloc_bridge); 245 246 247 void agp_put_bridge(struct agp_bridge_data *bridge) 248 { 249 kfree(bridge); 250 251 if (list_empty(&agp_bridges)) 252 agp_bridge = NULL; 253 } 254 EXPORT_SYMBOL(agp_put_bridge); 255 256 257 int agp_add_bridge(struct agp_bridge_data *bridge) 258 { 259 int error; 260 261 if (agp_off) 262 return -ENODEV; 263 264 if (!bridge->dev) { 265 printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n"); 266 return -EINVAL; 267 } 268 269 /* Grab reference on the chipset driver. */ 270 if (!try_module_get(bridge->driver->owner)) { 271 printk (KERN_INFO PFX "Couldn't lock chipset driver.\n"); 272 return -EINVAL; 273 } 274 275 error = agp_backend_initialize(bridge); 276 if (error) { 277 printk (KERN_INFO PFX "agp_backend_initialize() failed.\n"); 278 goto err_out; 279 } 280 281 if (list_empty(&agp_bridges)) { 282 error = agp_frontend_initialize(); 283 if (error) { 284 printk (KERN_INFO PFX "agp_frontend_initialize() failed.\n"); 285 goto frontend_err; 286 } 287 288 printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n", 289 bridge->driver->fetch_size(), bridge->gart_bus_addr); 290 291 } 292 293 list_add(&bridge->list, &agp_bridges); 294 return 0; 295 296 frontend_err: 297 agp_backend_cleanup(bridge); 298 err_out: 299 module_put(bridge->driver->owner); 300 agp_put_bridge(bridge); 301 return error; 302 } 303 EXPORT_SYMBOL_GPL(agp_add_bridge); 304 305 306 void agp_remove_bridge(struct agp_bridge_data *bridge) 307 { 308 agp_backend_cleanup(bridge); 309 list_del(&bridge->list); 310 if (list_empty(&agp_bridges)) 311 agp_frontend_cleanup(); 312 module_put(bridge->driver->owner); 313 } 314 EXPORT_SYMBOL_GPL(agp_remove_bridge); 315 316 int agp_off; 317 int agp_try_unsupported_boot; 318 EXPORT_SYMBOL(agp_off); 319 EXPORT_SYMBOL(agp_try_unsupported_boot); 320 321 static int __init agp_init(void) 322 { 323 if (!agp_off) 324 printk(KERN_INFO "Linux agpgart interface v%d.%d\n", 325 AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR); 326 return 0; 327 } 328 329 static void __exit agp_exit(void) 330 { 331 } 332 333 #ifndef MODULE 334 static __init int agp_setup(char *s) 335 { 336 if (!strcmp(s,"off")) 337 agp_off = 1; 338 if (!strcmp(s,"try_unsupported")) 339 agp_try_unsupported_boot = 1; 340 return 1; 341 } 342 __setup("agp=", agp_setup); 343 #endif 344 345 MODULE_AUTHOR("Dave Jones <davej@codemonkey.org.uk>"); 346 MODULE_DESCRIPTION("AGP GART driver"); 347 MODULE_LICENSE("GPL and additional rights"); 348 MODULE_ALIAS_MISCDEV(AGPGART_MINOR); 349 350 module_init(agp_init); 351 module_exit(agp_exit); 352 353