1 /* 2 * Common ACPI functions for hot plug platforms 3 * 4 * Copyright (C) 2006 Intel Corporation 5 * 6 * All rights reserved. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or (at 11 * your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 16 * NON INFRINGEMENT. See the GNU General Public License for more 17 * details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 22 * 23 * Send feedback to <kristen.c.accardi@intel.com> 24 * 25 */ 26 27 #include <linux/module.h> 28 #include <linux/moduleparam.h> 29 #include <linux/kernel.h> 30 #include <linux/types.h> 31 #include <linux/pci.h> 32 #include <linux/pci_hotplug.h> 33 #include <linux/acpi.h> 34 #include <linux/pci-acpi.h> 35 36 #define MY_NAME "acpi_pcihp" 37 38 #define dbg(fmt, arg...) do { if (debug_acpi) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0) 39 #define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg) 40 #define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg) 41 #define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg) 42 43 #define METHOD_NAME__SUN "_SUN" 44 #define METHOD_NAME_OSHP "OSHP" 45 46 static int debug_acpi; 47 48 static acpi_status 49 decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx) 50 { 51 int i; 52 union acpi_object *fields = record->package.elements; 53 u32 revision = fields[1].integer.value; 54 55 switch (revision) { 56 case 1: 57 if (record->package.count != 6) 58 return AE_ERROR; 59 for (i = 2; i < 6; i++) 60 if (fields[i].type != ACPI_TYPE_INTEGER) 61 return AE_ERROR; 62 hpx->t0 = &hpx->type0_data; 63 hpx->t0->revision = revision; 64 hpx->t0->cache_line_size = fields[2].integer.value; 65 hpx->t0->latency_timer = fields[3].integer.value; 66 hpx->t0->enable_serr = fields[4].integer.value; 67 hpx->t0->enable_perr = fields[5].integer.value; 68 break; 69 default: 70 printk(KERN_WARNING 71 "%s: Type 0 Revision %d record not supported\n", 72 __func__, revision); 73 return AE_ERROR; 74 } 75 return AE_OK; 76 } 77 78 static acpi_status 79 decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx) 80 { 81 int i; 82 union acpi_object *fields = record->package.elements; 83 u32 revision = fields[1].integer.value; 84 85 switch (revision) { 86 case 1: 87 if (record->package.count != 5) 88 return AE_ERROR; 89 for (i = 2; i < 5; i++) 90 if (fields[i].type != ACPI_TYPE_INTEGER) 91 return AE_ERROR; 92 hpx->t1 = &hpx->type1_data; 93 hpx->t1->revision = revision; 94 hpx->t1->max_mem_read = fields[2].integer.value; 95 hpx->t1->avg_max_split = fields[3].integer.value; 96 hpx->t1->tot_max_split = fields[4].integer.value; 97 break; 98 default: 99 printk(KERN_WARNING 100 "%s: Type 1 Revision %d record not supported\n", 101 __func__, revision); 102 return AE_ERROR; 103 } 104 return AE_OK; 105 } 106 107 static acpi_status 108 decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx) 109 { 110 int i; 111 union acpi_object *fields = record->package.elements; 112 u32 revision = fields[1].integer.value; 113 114 switch (revision) { 115 case 1: 116 if (record->package.count != 18) 117 return AE_ERROR; 118 for (i = 2; i < 18; i++) 119 if (fields[i].type != ACPI_TYPE_INTEGER) 120 return AE_ERROR; 121 hpx->t2 = &hpx->type2_data; 122 hpx->t2->revision = revision; 123 hpx->t2->unc_err_mask_and = fields[2].integer.value; 124 hpx->t2->unc_err_mask_or = fields[3].integer.value; 125 hpx->t2->unc_err_sever_and = fields[4].integer.value; 126 hpx->t2->unc_err_sever_or = fields[5].integer.value; 127 hpx->t2->cor_err_mask_and = fields[6].integer.value; 128 hpx->t2->cor_err_mask_or = fields[7].integer.value; 129 hpx->t2->adv_err_cap_and = fields[8].integer.value; 130 hpx->t2->adv_err_cap_or = fields[9].integer.value; 131 hpx->t2->pci_exp_devctl_and = fields[10].integer.value; 132 hpx->t2->pci_exp_devctl_or = fields[11].integer.value; 133 hpx->t2->pci_exp_lnkctl_and = fields[12].integer.value; 134 hpx->t2->pci_exp_lnkctl_or = fields[13].integer.value; 135 hpx->t2->sec_unc_err_sever_and = fields[14].integer.value; 136 hpx->t2->sec_unc_err_sever_or = fields[15].integer.value; 137 hpx->t2->sec_unc_err_mask_and = fields[16].integer.value; 138 hpx->t2->sec_unc_err_mask_or = fields[17].integer.value; 139 break; 140 default: 141 printk(KERN_WARNING 142 "%s: Type 2 Revision %d record not supported\n", 143 __func__, revision); 144 return AE_ERROR; 145 } 146 return AE_OK; 147 } 148 149 static acpi_status 150 acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx) 151 { 152 acpi_status status; 153 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 154 union acpi_object *package, *record, *fields; 155 u32 type; 156 int i; 157 158 /* Clear the return buffer with zeros */ 159 memset(hpx, 0, sizeof(struct hotplug_params)); 160 161 status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer); 162 if (ACPI_FAILURE(status)) 163 return status; 164 165 package = (union acpi_object *)buffer.pointer; 166 if (package->type != ACPI_TYPE_PACKAGE) { 167 status = AE_ERROR; 168 goto exit; 169 } 170 171 for (i = 0; i < package->package.count; i++) { 172 record = &package->package.elements[i]; 173 if (record->type != ACPI_TYPE_PACKAGE) { 174 status = AE_ERROR; 175 goto exit; 176 } 177 178 fields = record->package.elements; 179 if (fields[0].type != ACPI_TYPE_INTEGER || 180 fields[1].type != ACPI_TYPE_INTEGER) { 181 status = AE_ERROR; 182 goto exit; 183 } 184 185 type = fields[0].integer.value; 186 switch (type) { 187 case 0: 188 status = decode_type0_hpx_record(record, hpx); 189 if (ACPI_FAILURE(status)) 190 goto exit; 191 break; 192 case 1: 193 status = decode_type1_hpx_record(record, hpx); 194 if (ACPI_FAILURE(status)) 195 goto exit; 196 break; 197 case 2: 198 status = decode_type2_hpx_record(record, hpx); 199 if (ACPI_FAILURE(status)) 200 goto exit; 201 break; 202 default: 203 printk(KERN_ERR "%s: Type %d record not supported\n", 204 __func__, type); 205 status = AE_ERROR; 206 goto exit; 207 } 208 } 209 exit: 210 kfree(buffer.pointer); 211 return status; 212 } 213 214 static acpi_status 215 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp) 216 { 217 acpi_status status; 218 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 219 union acpi_object *package, *fields; 220 int i; 221 222 memset(hpp, 0, sizeof(struct hotplug_params)); 223 224 status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer); 225 if (ACPI_FAILURE(status)) 226 return status; 227 228 package = (union acpi_object *) buffer.pointer; 229 if (package->type != ACPI_TYPE_PACKAGE || 230 package->package.count != 4) { 231 status = AE_ERROR; 232 goto exit; 233 } 234 235 fields = package->package.elements; 236 for (i = 0; i < 4; i++) { 237 if (fields[i].type != ACPI_TYPE_INTEGER) { 238 status = AE_ERROR; 239 goto exit; 240 } 241 } 242 243 hpp->t0 = &hpp->type0_data; 244 hpp->t0->revision = 1; 245 hpp->t0->cache_line_size = fields[0].integer.value; 246 hpp->t0->latency_timer = fields[1].integer.value; 247 hpp->t0->enable_serr = fields[2].integer.value; 248 hpp->t0->enable_perr = fields[3].integer.value; 249 250 exit: 251 kfree(buffer.pointer); 252 return status; 253 } 254 255 256 257 /* acpi_run_oshp - get control of hotplug from the firmware 258 * 259 * @handle - the handle of the hotplug controller. 260 */ 261 static acpi_status acpi_run_oshp(acpi_handle handle) 262 { 263 acpi_status status; 264 struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL }; 265 266 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string); 267 268 /* run OSHP */ 269 status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL); 270 if (ACPI_FAILURE(status)) 271 if (status != AE_NOT_FOUND) 272 printk(KERN_ERR "%s:%s OSHP fails=0x%x\n", 273 __func__, (char *)string.pointer, status); 274 else 275 dbg("%s:%s OSHP not found\n", 276 __func__, (char *)string.pointer); 277 else 278 pr_debug("%s:%s OSHP passes\n", __func__, 279 (char *)string.pointer); 280 281 kfree(string.pointer); 282 return status; 283 } 284 285 /* pci_get_hp_params 286 * 287 * @dev - the pci_dev for which we want parameters 288 * @hpp - allocated by the caller 289 */ 290 int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp) 291 { 292 acpi_status status; 293 acpi_handle handle, phandle; 294 struct pci_bus *pbus; 295 296 handle = NULL; 297 for (pbus = dev->bus; pbus; pbus = pbus->parent) { 298 handle = acpi_pci_get_bridge_handle(pbus); 299 if (handle) 300 break; 301 } 302 303 /* 304 * _HPP settings apply to all child buses, until another _HPP is 305 * encountered. If we don't find an _HPP for the input pci dev, 306 * look for it in the parent device scope since that would apply to 307 * this pci dev. 308 */ 309 while (handle) { 310 status = acpi_run_hpx(handle, hpp); 311 if (ACPI_SUCCESS(status)) 312 return 0; 313 status = acpi_run_hpp(handle, hpp); 314 if (ACPI_SUCCESS(status)) 315 return 0; 316 if (acpi_is_root_bridge(handle)) 317 break; 318 status = acpi_get_parent(handle, &phandle); 319 if (ACPI_FAILURE(status)) 320 break; 321 handle = phandle; 322 } 323 return -ENODEV; 324 } 325 EXPORT_SYMBOL_GPL(pci_get_hp_params); 326 327 /** 328 * acpi_get_hp_hw_control_from_firmware 329 * @dev: the pci_dev of the bridge that has a hotplug controller 330 * @flags: requested control bits for _OSC 331 * 332 * Attempt to take hotplug control from firmware. 333 */ 334 int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags) 335 { 336 acpi_status status; 337 acpi_handle chandle, handle; 338 struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL }; 339 340 flags &= (OSC_PCI_EXPRESS_NATIVE_HP_CONTROL | 341 OSC_SHPC_NATIVE_HP_CONTROL | 342 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL); 343 if (!flags) { 344 err("Invalid flags %u specified!\n", flags); 345 return -EINVAL; 346 } 347 348 /* 349 * Per PCI firmware specification, we should run the ACPI _OSC 350 * method to get control of hotplug hardware before using it. If 351 * an _OSC is missing, we look for an OSHP to do the same thing. 352 * To handle different BIOS behavior, we look for _OSC on a root 353 * bridge preferentially (according to PCI fw spec). Later for 354 * OSHP within the scope of the hotplug controller and its parents, 355 * upto the host bridge under which this controller exists. 356 */ 357 handle = acpi_find_root_bridge_handle(pdev); 358 if (handle) { 359 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string); 360 dbg("Trying to get hotplug control for %s\n", 361 (char *)string.pointer); 362 status = acpi_pci_osc_control_set(handle, flags); 363 if (ACPI_SUCCESS(status)) 364 goto got_one; 365 if (status == AE_SUPPORT) 366 goto no_control; 367 kfree(string.pointer); 368 string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL }; 369 } 370 371 handle = DEVICE_ACPI_HANDLE(&pdev->dev); 372 if (!handle) { 373 /* 374 * This hotplug controller was not listed in the ACPI name 375 * space at all. Try to get acpi handle of parent pci bus. 376 */ 377 struct pci_bus *pbus; 378 for (pbus = pdev->bus; pbus; pbus = pbus->parent) { 379 handle = acpi_pci_get_bridge_handle(pbus); 380 if (handle) 381 break; 382 } 383 } 384 385 while (handle) { 386 acpi_get_name(handle, ACPI_FULL_PATHNAME, &string); 387 dbg("Trying to get hotplug control for %s \n", 388 (char *)string.pointer); 389 status = acpi_run_oshp(handle); 390 if (ACPI_SUCCESS(status)) 391 goto got_one; 392 if (acpi_is_root_bridge(handle)) 393 break; 394 chandle = handle; 395 status = acpi_get_parent(chandle, &handle); 396 if (ACPI_FAILURE(status)) 397 break; 398 } 399 no_control: 400 dbg("Cannot get control of hotplug hardware for pci %s\n", 401 pci_name(pdev)); 402 kfree(string.pointer); 403 return -ENODEV; 404 got_one: 405 dbg("Gained control for hotplug HW for pci %s (%s)\n", 406 pci_name(pdev), (char *)string.pointer); 407 kfree(string.pointer); 408 return 0; 409 } 410 EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware); 411 412 static int is_ejectable(acpi_handle handle) 413 { 414 acpi_status status; 415 acpi_handle tmp; 416 unsigned long long removable; 417 status = acpi_get_handle(handle, "_ADR", &tmp); 418 if (ACPI_FAILURE(status)) 419 return 0; 420 status = acpi_get_handle(handle, "_EJ0", &tmp); 421 if (ACPI_SUCCESS(status)) 422 return 1; 423 status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable); 424 if (ACPI_SUCCESS(status) && removable) 425 return 1; 426 return 0; 427 } 428 429 /** 430 * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot 431 * @pbus: the PCI bus of the PCI slot corresponding to 'handle' 432 * @handle: ACPI handle to check 433 * 434 * Return 1 if handle is ejectable PCI slot, 0 otherwise. 435 */ 436 int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle) 437 { 438 acpi_handle bridge_handle, parent_handle; 439 440 if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus))) 441 return 0; 442 if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle)))) 443 return 0; 444 if (bridge_handle != parent_handle) 445 return 0; 446 return is_ejectable(handle); 447 } 448 EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable); 449 450 static acpi_status 451 check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv) 452 { 453 int *found = (int *)context; 454 if (is_ejectable(handle)) { 455 *found = 1; 456 return AE_CTRL_TERMINATE; 457 } 458 return AE_OK; 459 } 460 461 /** 462 * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots 463 * @handle - handle of the PCI bus to scan 464 * 465 * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise. 466 */ 467 int acpi_pci_detect_ejectable(acpi_handle handle) 468 { 469 int found = 0; 470 471 if (!handle) 472 return found; 473 474 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, 475 check_hotplug, NULL, (void *)&found, NULL); 476 return found; 477 } 478 EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable); 479 480 module_param(debug_acpi, bool, 0644); 481 MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not"); 482