1 /* 2 * PowerNV OPAL Dump Interface 3 * 4 * Copyright 2013,2014 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/kobject.h> 13 #include <linux/mm.h> 14 #include <linux/slab.h> 15 #include <linux/vmalloc.h> 16 #include <linux/pagemap.h> 17 #include <linux/delay.h> 18 19 #include <asm/opal.h> 20 21 #define DUMP_TYPE_FSP 0x01 22 23 struct dump_obj { 24 struct kobject kobj; 25 struct bin_attribute dump_attr; 26 uint32_t id; /* becomes object name */ 27 uint32_t type; 28 uint32_t size; 29 char *buffer; 30 }; 31 #define to_dump_obj(x) container_of(x, struct dump_obj, kobj) 32 33 struct dump_attribute { 34 struct attribute attr; 35 ssize_t (*show)(struct dump_obj *dump, struct dump_attribute *attr, 36 char *buf); 37 ssize_t (*store)(struct dump_obj *dump, struct dump_attribute *attr, 38 const char *buf, size_t count); 39 }; 40 #define to_dump_attr(x) container_of(x, struct dump_attribute, attr) 41 42 static ssize_t dump_id_show(struct dump_obj *dump_obj, 43 struct dump_attribute *attr, 44 char *buf) 45 { 46 return sprintf(buf, "0x%x\n", dump_obj->id); 47 } 48 49 static const char* dump_type_to_string(uint32_t type) 50 { 51 switch (type) { 52 case 0x01: return "SP Dump"; 53 case 0x02: return "System/Platform Dump"; 54 case 0x03: return "SMA Dump"; 55 default: return "unknown"; 56 } 57 } 58 59 static ssize_t dump_type_show(struct dump_obj *dump_obj, 60 struct dump_attribute *attr, 61 char *buf) 62 { 63 64 return sprintf(buf, "0x%x %s\n", dump_obj->type, 65 dump_type_to_string(dump_obj->type)); 66 } 67 68 static ssize_t dump_ack_show(struct dump_obj *dump_obj, 69 struct dump_attribute *attr, 70 char *buf) 71 { 72 return sprintf(buf, "ack - acknowledge dump\n"); 73 } 74 75 /* 76 * Send acknowledgement to OPAL 77 */ 78 static int64_t dump_send_ack(uint32_t dump_id) 79 { 80 int rc; 81 82 rc = opal_dump_ack(dump_id); 83 if (rc) 84 pr_warn("%s: Failed to send ack to Dump ID 0x%x (%d)\n", 85 __func__, dump_id, rc); 86 return rc; 87 } 88 89 static ssize_t dump_ack_store(struct dump_obj *dump_obj, 90 struct dump_attribute *attr, 91 const char *buf, 92 size_t count) 93 { 94 dump_send_ack(dump_obj->id); 95 sysfs_remove_file_self(&dump_obj->kobj, &attr->attr); 96 kobject_put(&dump_obj->kobj); 97 return count; 98 } 99 100 /* Attributes of a dump 101 * The binary attribute of the dump itself is dynamic 102 * due to the dynamic size of the dump 103 */ 104 static struct dump_attribute id_attribute = 105 __ATTR(id, 0666, dump_id_show, NULL); 106 static struct dump_attribute type_attribute = 107 __ATTR(type, 0666, dump_type_show, NULL); 108 static struct dump_attribute ack_attribute = 109 __ATTR(acknowledge, 0660, dump_ack_show, dump_ack_store); 110 111 static ssize_t init_dump_show(struct dump_obj *dump_obj, 112 struct dump_attribute *attr, 113 char *buf) 114 { 115 return sprintf(buf, "1 - initiate dump\n"); 116 } 117 118 static int64_t dump_fips_init(uint8_t type) 119 { 120 int rc; 121 122 rc = opal_dump_init(type); 123 if (rc) 124 pr_warn("%s: Failed to initiate FipS dump (%d)\n", 125 __func__, rc); 126 return rc; 127 } 128 129 static ssize_t init_dump_store(struct dump_obj *dump_obj, 130 struct dump_attribute *attr, 131 const char *buf, 132 size_t count) 133 { 134 dump_fips_init(DUMP_TYPE_FSP); 135 pr_info("%s: Initiated FSP dump\n", __func__); 136 return count; 137 } 138 139 static struct dump_attribute initiate_attribute = 140 __ATTR(initiate_dump, 0600, init_dump_show, init_dump_store); 141 142 static struct attribute *initiate_attrs[] = { 143 &initiate_attribute.attr, 144 NULL, 145 }; 146 147 static struct attribute_group initiate_attr_group = { 148 .attrs = initiate_attrs, 149 }; 150 151 static struct kset *dump_kset; 152 153 static ssize_t dump_attr_show(struct kobject *kobj, 154 struct attribute *attr, 155 char *buf) 156 { 157 struct dump_attribute *attribute; 158 struct dump_obj *dump; 159 160 attribute = to_dump_attr(attr); 161 dump = to_dump_obj(kobj); 162 163 if (!attribute->show) 164 return -EIO; 165 166 return attribute->show(dump, attribute, buf); 167 } 168 169 static ssize_t dump_attr_store(struct kobject *kobj, 170 struct attribute *attr, 171 const char *buf, size_t len) 172 { 173 struct dump_attribute *attribute; 174 struct dump_obj *dump; 175 176 attribute = to_dump_attr(attr); 177 dump = to_dump_obj(kobj); 178 179 if (!attribute->store) 180 return -EIO; 181 182 return attribute->store(dump, attribute, buf, len); 183 } 184 185 static const struct sysfs_ops dump_sysfs_ops = { 186 .show = dump_attr_show, 187 .store = dump_attr_store, 188 }; 189 190 static void dump_release(struct kobject *kobj) 191 { 192 struct dump_obj *dump; 193 194 dump = to_dump_obj(kobj); 195 vfree(dump->buffer); 196 kfree(dump); 197 } 198 199 static struct attribute *dump_default_attrs[] = { 200 &id_attribute.attr, 201 &type_attribute.attr, 202 &ack_attribute.attr, 203 NULL, 204 }; 205 206 static struct kobj_type dump_ktype = { 207 .sysfs_ops = &dump_sysfs_ops, 208 .release = &dump_release, 209 .default_attrs = dump_default_attrs, 210 }; 211 212 static int64_t dump_read_info(uint32_t *id, uint32_t *size, uint32_t *type) 213 { 214 int rc; 215 *type = 0xffffffff; 216 217 rc = opal_dump_info2(id, size, type); 218 219 if (rc == OPAL_PARAMETER) 220 rc = opal_dump_info(id, size); 221 222 if (rc) 223 pr_warn("%s: Failed to get dump info (%d)\n", 224 __func__, rc); 225 return rc; 226 } 227 228 static int64_t dump_read_data(struct dump_obj *dump) 229 { 230 struct opal_sg_list *list; 231 uint64_t addr; 232 int64_t rc; 233 234 /* Allocate memory */ 235 dump->buffer = vzalloc(PAGE_ALIGN(dump->size)); 236 if (!dump->buffer) { 237 pr_err("%s : Failed to allocate memory\n", __func__); 238 rc = -ENOMEM; 239 goto out; 240 } 241 242 /* Generate SG list */ 243 list = opal_vmalloc_to_sg_list(dump->buffer, dump->size); 244 if (!list) { 245 rc = -ENOMEM; 246 goto out; 247 } 248 249 /* First entry address */ 250 addr = __pa(list); 251 252 /* Fetch data */ 253 rc = OPAL_BUSY_EVENT; 254 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 255 rc = opal_dump_read(dump->id, addr); 256 if (rc == OPAL_BUSY_EVENT) { 257 opal_poll_events(NULL); 258 msleep(20); 259 } 260 } 261 262 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) 263 pr_warn("%s: Extract dump failed for ID 0x%x\n", 264 __func__, dump->id); 265 266 /* Free SG list */ 267 opal_free_sg_list(list); 268 269 out: 270 return rc; 271 } 272 273 static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj, 274 struct bin_attribute *bin_attr, 275 char *buffer, loff_t pos, size_t count) 276 { 277 ssize_t rc; 278 279 struct dump_obj *dump = to_dump_obj(kobj); 280 281 if (!dump->buffer) { 282 rc = dump_read_data(dump); 283 284 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) { 285 vfree(dump->buffer); 286 dump->buffer = NULL; 287 288 return -EIO; 289 } 290 if (rc == OPAL_PARTIAL) { 291 /* On a partial read, we just return EIO 292 * and rely on userspace to ask us to try 293 * again. 294 */ 295 pr_info("%s: Platform dump partially read.ID = 0x%x\n", 296 __func__, dump->id); 297 return -EIO; 298 } 299 } 300 301 memcpy(buffer, dump->buffer + pos, count); 302 303 /* You may think we could free the dump buffer now and retrieve 304 * it again later if needed, but due to current firmware limitation, 305 * that's not the case. So, once read into userspace once, 306 * we keep the dump around until it's acknowledged by userspace. 307 */ 308 309 return count; 310 } 311 312 static struct dump_obj *create_dump_obj(uint32_t id, size_t size, 313 uint32_t type) 314 { 315 struct dump_obj *dump; 316 int rc; 317 318 dump = kzalloc(sizeof(*dump), GFP_KERNEL); 319 if (!dump) 320 return NULL; 321 322 dump->kobj.kset = dump_kset; 323 324 kobject_init(&dump->kobj, &dump_ktype); 325 326 sysfs_bin_attr_init(&dump->dump_attr); 327 328 dump->dump_attr.attr.name = "dump"; 329 dump->dump_attr.attr.mode = 0400; 330 dump->dump_attr.size = size; 331 dump->dump_attr.read = dump_attr_read; 332 333 dump->id = id; 334 dump->size = size; 335 dump->type = type; 336 337 rc = kobject_add(&dump->kobj, NULL, "0x%x-0x%x", type, id); 338 if (rc) { 339 kobject_put(&dump->kobj); 340 return NULL; 341 } 342 343 rc = sysfs_create_bin_file(&dump->kobj, &dump->dump_attr); 344 if (rc) { 345 kobject_put(&dump->kobj); 346 return NULL; 347 } 348 349 pr_info("%s: New platform dump. ID = 0x%x Size %u\n", 350 __func__, dump->id, dump->size); 351 352 kobject_uevent(&dump->kobj, KOBJ_ADD); 353 354 return dump; 355 } 356 357 static int process_dump(void) 358 { 359 int rc; 360 uint32_t dump_id, dump_size, dump_type; 361 struct dump_obj *dump; 362 char name[22]; 363 364 rc = dump_read_info(&dump_id, &dump_size, &dump_type); 365 if (rc != OPAL_SUCCESS) 366 return rc; 367 368 sprintf(name, "0x%x-0x%x", dump_type, dump_id); 369 370 /* we may get notified twice, let's handle 371 * that gracefully and not create two conflicting 372 * entries. 373 */ 374 if (kset_find_obj(dump_kset, name)) 375 return 0; 376 377 dump = create_dump_obj(dump_id, dump_size, dump_type); 378 if (!dump) 379 return -1; 380 381 return 0; 382 } 383 384 static void dump_work_fn(struct work_struct *work) 385 { 386 process_dump(); 387 } 388 389 static DECLARE_WORK(dump_work, dump_work_fn); 390 391 static void schedule_process_dump(void) 392 { 393 schedule_work(&dump_work); 394 } 395 396 /* 397 * New dump available notification 398 * 399 * Once we get notification, we add sysfs entries for it. 400 * We only fetch the dump on demand, and create sysfs asynchronously. 401 */ 402 static int dump_event(struct notifier_block *nb, 403 unsigned long events, void *change) 404 { 405 if (events & OPAL_EVENT_DUMP_AVAIL) 406 schedule_process_dump(); 407 408 return 0; 409 } 410 411 static struct notifier_block dump_nb = { 412 .notifier_call = dump_event, 413 .next = NULL, 414 .priority = 0 415 }; 416 417 void __init opal_platform_dump_init(void) 418 { 419 int rc; 420 421 dump_kset = kset_create_and_add("dump", NULL, opal_kobj); 422 if (!dump_kset) { 423 pr_warn("%s: Failed to create dump kset\n", __func__); 424 return; 425 } 426 427 rc = sysfs_create_group(&dump_kset->kobj, &initiate_attr_group); 428 if (rc) { 429 pr_warn("%s: Failed to create initiate dump attr group\n", 430 __func__); 431 kobject_put(&dump_kset->kobj); 432 return; 433 } 434 435 rc = opal_notifier_register(&dump_nb); 436 if (rc) { 437 pr_warn("%s: Can't register OPAL event notifier (%d)\n", 438 __func__, rc); 439 return; 440 } 441 442 opal_dump_resend_notification(); 443 } 444