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 #include <linux/interrupt.h> 19 20 #include <asm/opal.h> 21 22 #define DUMP_TYPE_FSP 0x01 23 24 struct dump_obj { 25 struct kobject kobj; 26 struct bin_attribute dump_attr; 27 uint32_t id; /* becomes object name */ 28 uint32_t type; 29 uint32_t size; 30 char *buffer; 31 }; 32 #define to_dump_obj(x) container_of(x, struct dump_obj, kobj) 33 34 struct dump_attribute { 35 struct attribute attr; 36 ssize_t (*show)(struct dump_obj *dump, struct dump_attribute *attr, 37 char *buf); 38 ssize_t (*store)(struct dump_obj *dump, struct dump_attribute *attr, 39 const char *buf, size_t count); 40 }; 41 #define to_dump_attr(x) container_of(x, struct dump_attribute, attr) 42 43 static ssize_t dump_id_show(struct dump_obj *dump_obj, 44 struct dump_attribute *attr, 45 char *buf) 46 { 47 return sprintf(buf, "0x%x\n", dump_obj->id); 48 } 49 50 static const char* dump_type_to_string(uint32_t type) 51 { 52 switch (type) { 53 case 0x01: return "SP Dump"; 54 case 0x02: return "System/Platform Dump"; 55 case 0x03: return "SMA Dump"; 56 default: return "unknown"; 57 } 58 } 59 60 static ssize_t dump_type_show(struct dump_obj *dump_obj, 61 struct dump_attribute *attr, 62 char *buf) 63 { 64 65 return sprintf(buf, "0x%x %s\n", dump_obj->type, 66 dump_type_to_string(dump_obj->type)); 67 } 68 69 static ssize_t dump_ack_show(struct dump_obj *dump_obj, 70 struct dump_attribute *attr, 71 char *buf) 72 { 73 return sprintf(buf, "ack - acknowledge dump\n"); 74 } 75 76 /* 77 * Send acknowledgement to OPAL 78 */ 79 static int64_t dump_send_ack(uint32_t dump_id) 80 { 81 int rc; 82 83 rc = opal_dump_ack(dump_id); 84 if (rc) 85 pr_warn("%s: Failed to send ack to Dump ID 0x%x (%d)\n", 86 __func__, dump_id, rc); 87 return rc; 88 } 89 90 static ssize_t dump_ack_store(struct dump_obj *dump_obj, 91 struct dump_attribute *attr, 92 const char *buf, 93 size_t count) 94 { 95 dump_send_ack(dump_obj->id); 96 sysfs_remove_file_self(&dump_obj->kobj, &attr->attr); 97 kobject_put(&dump_obj->kobj); 98 return count; 99 } 100 101 /* Attributes of a dump 102 * The binary attribute of the dump itself is dynamic 103 * due to the dynamic size of the dump 104 */ 105 static struct dump_attribute id_attribute = 106 __ATTR(id, S_IRUGO, dump_id_show, NULL); 107 static struct dump_attribute type_attribute = 108 __ATTR(type, S_IRUGO, dump_type_show, NULL); 109 static struct dump_attribute ack_attribute = 110 __ATTR(acknowledge, 0660, dump_ack_show, dump_ack_store); 111 112 static ssize_t init_dump_show(struct dump_obj *dump_obj, 113 struct dump_attribute *attr, 114 char *buf) 115 { 116 return sprintf(buf, "1 - initiate Service Processor(FSP) dump\n"); 117 } 118 119 static int64_t dump_fips_init(uint8_t type) 120 { 121 int rc; 122 123 rc = opal_dump_init(type); 124 if (rc) 125 pr_warn("%s: Failed to initiate FSP dump (%d)\n", 126 __func__, rc); 127 return rc; 128 } 129 130 static ssize_t init_dump_store(struct dump_obj *dump_obj, 131 struct dump_attribute *attr, 132 const char *buf, 133 size_t count) 134 { 135 int rc; 136 137 rc = dump_fips_init(DUMP_TYPE_FSP); 138 if (rc == OPAL_SUCCESS) 139 pr_info("%s: Initiated FSP dump\n", __func__); 140 141 return count; 142 } 143 144 static struct dump_attribute initiate_attribute = 145 __ATTR(initiate_dump, 0600, init_dump_show, init_dump_store); 146 147 static struct attribute *initiate_attrs[] = { 148 &initiate_attribute.attr, 149 NULL, 150 }; 151 152 static struct attribute_group initiate_attr_group = { 153 .attrs = initiate_attrs, 154 }; 155 156 static struct kset *dump_kset; 157 158 static ssize_t dump_attr_show(struct kobject *kobj, 159 struct attribute *attr, 160 char *buf) 161 { 162 struct dump_attribute *attribute; 163 struct dump_obj *dump; 164 165 attribute = to_dump_attr(attr); 166 dump = to_dump_obj(kobj); 167 168 if (!attribute->show) 169 return -EIO; 170 171 return attribute->show(dump, attribute, buf); 172 } 173 174 static ssize_t dump_attr_store(struct kobject *kobj, 175 struct attribute *attr, 176 const char *buf, size_t len) 177 { 178 struct dump_attribute *attribute; 179 struct dump_obj *dump; 180 181 attribute = to_dump_attr(attr); 182 dump = to_dump_obj(kobj); 183 184 if (!attribute->store) 185 return -EIO; 186 187 return attribute->store(dump, attribute, buf, len); 188 } 189 190 static const struct sysfs_ops dump_sysfs_ops = { 191 .show = dump_attr_show, 192 .store = dump_attr_store, 193 }; 194 195 static void dump_release(struct kobject *kobj) 196 { 197 struct dump_obj *dump; 198 199 dump = to_dump_obj(kobj); 200 vfree(dump->buffer); 201 kfree(dump); 202 } 203 204 static struct attribute *dump_default_attrs[] = { 205 &id_attribute.attr, 206 &type_attribute.attr, 207 &ack_attribute.attr, 208 NULL, 209 }; 210 211 static struct kobj_type dump_ktype = { 212 .sysfs_ops = &dump_sysfs_ops, 213 .release = &dump_release, 214 .default_attrs = dump_default_attrs, 215 }; 216 217 static int64_t dump_read_info(uint32_t *dump_id, uint32_t *dump_size, uint32_t *dump_type) 218 { 219 __be32 id, size, type; 220 int rc; 221 222 type = cpu_to_be32(0xffffffff); 223 224 rc = opal_dump_info2(&id, &size, &type); 225 if (rc == OPAL_PARAMETER) 226 rc = opal_dump_info(&id, &size); 227 228 *dump_id = be32_to_cpu(id); 229 *dump_size = be32_to_cpu(size); 230 *dump_type = be32_to_cpu(type); 231 232 if (rc) 233 pr_warn("%s: Failed to get dump info (%d)\n", 234 __func__, rc); 235 return rc; 236 } 237 238 static int64_t dump_read_data(struct dump_obj *dump) 239 { 240 struct opal_sg_list *list; 241 uint64_t addr; 242 int64_t rc; 243 244 /* Allocate memory */ 245 dump->buffer = vzalloc(PAGE_ALIGN(dump->size)); 246 if (!dump->buffer) { 247 pr_err("%s : Failed to allocate memory\n", __func__); 248 rc = -ENOMEM; 249 goto out; 250 } 251 252 /* Generate SG list */ 253 list = opal_vmalloc_to_sg_list(dump->buffer, dump->size); 254 if (!list) { 255 rc = -ENOMEM; 256 goto out; 257 } 258 259 /* First entry address */ 260 addr = __pa(list); 261 262 /* Fetch data */ 263 rc = OPAL_BUSY_EVENT; 264 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 265 rc = opal_dump_read(dump->id, addr); 266 if (rc == OPAL_BUSY_EVENT) { 267 opal_poll_events(NULL); 268 msleep(20); 269 } 270 } 271 272 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) 273 pr_warn("%s: Extract dump failed for ID 0x%x\n", 274 __func__, dump->id); 275 276 /* Free SG list */ 277 opal_free_sg_list(list); 278 279 out: 280 return rc; 281 } 282 283 static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj, 284 struct bin_attribute *bin_attr, 285 char *buffer, loff_t pos, size_t count) 286 { 287 ssize_t rc; 288 289 struct dump_obj *dump = to_dump_obj(kobj); 290 291 if (!dump->buffer) { 292 rc = dump_read_data(dump); 293 294 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) { 295 vfree(dump->buffer); 296 dump->buffer = NULL; 297 298 return -EIO; 299 } 300 if (rc == OPAL_PARTIAL) { 301 /* On a partial read, we just return EIO 302 * and rely on userspace to ask us to try 303 * again. 304 */ 305 pr_info("%s: Platform dump partially read. ID = 0x%x\n", 306 __func__, dump->id); 307 return -EIO; 308 } 309 } 310 311 memcpy(buffer, dump->buffer + pos, count); 312 313 /* You may think we could free the dump buffer now and retrieve 314 * it again later if needed, but due to current firmware limitation, 315 * that's not the case. So, once read into userspace once, 316 * we keep the dump around until it's acknowledged by userspace. 317 */ 318 319 return count; 320 } 321 322 static struct dump_obj *create_dump_obj(uint32_t id, size_t size, 323 uint32_t type) 324 { 325 struct dump_obj *dump; 326 int rc; 327 328 dump = kzalloc(sizeof(*dump), GFP_KERNEL); 329 if (!dump) 330 return NULL; 331 332 dump->kobj.kset = dump_kset; 333 334 kobject_init(&dump->kobj, &dump_ktype); 335 336 sysfs_bin_attr_init(&dump->dump_attr); 337 338 dump->dump_attr.attr.name = "dump"; 339 dump->dump_attr.attr.mode = 0400; 340 dump->dump_attr.size = size; 341 dump->dump_attr.read = dump_attr_read; 342 343 dump->id = id; 344 dump->size = size; 345 dump->type = type; 346 347 rc = kobject_add(&dump->kobj, NULL, "0x%x-0x%x", type, id); 348 if (rc) { 349 kobject_put(&dump->kobj); 350 return NULL; 351 } 352 353 rc = sysfs_create_bin_file(&dump->kobj, &dump->dump_attr); 354 if (rc) { 355 kobject_put(&dump->kobj); 356 return NULL; 357 } 358 359 pr_info("%s: New platform dump. ID = 0x%x Size %u\n", 360 __func__, dump->id, dump->size); 361 362 kobject_uevent(&dump->kobj, KOBJ_ADD); 363 364 return dump; 365 } 366 367 static irqreturn_t process_dump(int irq, void *data) 368 { 369 int rc; 370 uint32_t dump_id, dump_size, dump_type; 371 struct dump_obj *dump; 372 char name[22]; 373 374 rc = dump_read_info(&dump_id, &dump_size, &dump_type); 375 if (rc != OPAL_SUCCESS) 376 return rc; 377 378 sprintf(name, "0x%x-0x%x", dump_type, dump_id); 379 380 /* we may get notified twice, let's handle 381 * that gracefully and not create two conflicting 382 * entries. 383 */ 384 if (kset_find_obj(dump_kset, name)) 385 return 0; 386 387 dump = create_dump_obj(dump_id, dump_size, dump_type); 388 if (!dump) 389 return -1; 390 391 return IRQ_HANDLED; 392 } 393 394 void __init opal_platform_dump_init(void) 395 { 396 int rc; 397 int dump_irq; 398 399 /* ELOG not supported by firmware */ 400 if (!opal_check_token(OPAL_DUMP_READ)) 401 return; 402 403 dump_kset = kset_create_and_add("dump", NULL, opal_kobj); 404 if (!dump_kset) { 405 pr_warn("%s: Failed to create dump kset\n", __func__); 406 return; 407 } 408 409 rc = sysfs_create_group(&dump_kset->kobj, &initiate_attr_group); 410 if (rc) { 411 pr_warn("%s: Failed to create initiate dump attr group\n", 412 __func__); 413 kobject_put(&dump_kset->kobj); 414 return; 415 } 416 417 dump_irq = opal_event_request(ilog2(OPAL_EVENT_DUMP_AVAIL)); 418 if (!dump_irq) { 419 pr_err("%s: Can't register OPAL event irq (%d)\n", 420 __func__, dump_irq); 421 return; 422 } 423 424 rc = request_threaded_irq(dump_irq, NULL, process_dump, 425 IRQF_TRIGGER_HIGH | IRQF_ONESHOT, 426 "opal-dump", NULL); 427 if (rc) { 428 pr_err("%s: Can't request OPAL event irq (%d)\n", 429 __func__, rc); 430 return; 431 } 432 433 if (opal_check_token(OPAL_DUMP_RESEND)) 434 opal_dump_resend_notification(); 435 } 436