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