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, 0444, dump_id_show, NULL); 107 static struct dump_attribute type_attribute = 108 __ATTR(type, 0444, 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 if (rc) { 229 pr_warn("%s: Failed to get dump info (%d)\n", 230 __func__, rc); 231 return rc; 232 } 233 234 *dump_id = be32_to_cpu(id); 235 *dump_size = be32_to_cpu(size); 236 *dump_type = be32_to_cpu(type); 237 238 return rc; 239 } 240 241 static int64_t dump_read_data(struct dump_obj *dump) 242 { 243 struct opal_sg_list *list; 244 uint64_t addr; 245 int64_t rc; 246 247 /* Allocate memory */ 248 dump->buffer = vzalloc(PAGE_ALIGN(dump->size)); 249 if (!dump->buffer) { 250 pr_err("%s : Failed to allocate memory\n", __func__); 251 rc = -ENOMEM; 252 goto out; 253 } 254 255 /* Generate SG list */ 256 list = opal_vmalloc_to_sg_list(dump->buffer, dump->size); 257 if (!list) { 258 rc = -ENOMEM; 259 goto out; 260 } 261 262 /* First entry address */ 263 addr = __pa(list); 264 265 /* Fetch data */ 266 rc = OPAL_BUSY_EVENT; 267 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 268 rc = opal_dump_read(dump->id, addr); 269 if (rc == OPAL_BUSY_EVENT) { 270 opal_poll_events(NULL); 271 msleep(20); 272 } 273 } 274 275 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) 276 pr_warn("%s: Extract dump failed for ID 0x%x\n", 277 __func__, dump->id); 278 279 /* Free SG list */ 280 opal_free_sg_list(list); 281 282 out: 283 return rc; 284 } 285 286 static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj, 287 struct bin_attribute *bin_attr, 288 char *buffer, loff_t pos, size_t count) 289 { 290 ssize_t rc; 291 292 struct dump_obj *dump = to_dump_obj(kobj); 293 294 if (!dump->buffer) { 295 rc = dump_read_data(dump); 296 297 if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) { 298 vfree(dump->buffer); 299 dump->buffer = NULL; 300 301 return -EIO; 302 } 303 if (rc == OPAL_PARTIAL) { 304 /* On a partial read, we just return EIO 305 * and rely on userspace to ask us to try 306 * again. 307 */ 308 pr_info("%s: Platform dump partially read. ID = 0x%x\n", 309 __func__, dump->id); 310 return -EIO; 311 } 312 } 313 314 memcpy(buffer, dump->buffer + pos, count); 315 316 /* You may think we could free the dump buffer now and retrieve 317 * it again later if needed, but due to current firmware limitation, 318 * that's not the case. So, once read into userspace once, 319 * we keep the dump around until it's acknowledged by userspace. 320 */ 321 322 return count; 323 } 324 325 static struct dump_obj *create_dump_obj(uint32_t id, size_t size, 326 uint32_t type) 327 { 328 struct dump_obj *dump; 329 int rc; 330 331 dump = kzalloc(sizeof(*dump), GFP_KERNEL); 332 if (!dump) 333 return NULL; 334 335 dump->kobj.kset = dump_kset; 336 337 kobject_init(&dump->kobj, &dump_ktype); 338 339 sysfs_bin_attr_init(&dump->dump_attr); 340 341 dump->dump_attr.attr.name = "dump"; 342 dump->dump_attr.attr.mode = 0400; 343 dump->dump_attr.size = size; 344 dump->dump_attr.read = dump_attr_read; 345 346 dump->id = id; 347 dump->size = size; 348 dump->type = type; 349 350 rc = kobject_add(&dump->kobj, NULL, "0x%x-0x%x", type, id); 351 if (rc) { 352 kobject_put(&dump->kobj); 353 return NULL; 354 } 355 356 rc = sysfs_create_bin_file(&dump->kobj, &dump->dump_attr); 357 if (rc) { 358 kobject_put(&dump->kobj); 359 return NULL; 360 } 361 362 pr_info("%s: New platform dump. ID = 0x%x Size %u\n", 363 __func__, dump->id, dump->size); 364 365 kobject_uevent(&dump->kobj, KOBJ_ADD); 366 367 return dump; 368 } 369 370 static irqreturn_t process_dump(int irq, void *data) 371 { 372 int rc; 373 uint32_t dump_id, dump_size, dump_type; 374 char name[22]; 375 struct kobject *kobj; 376 377 rc = dump_read_info(&dump_id, &dump_size, &dump_type); 378 if (rc != OPAL_SUCCESS) 379 return IRQ_HANDLED; 380 381 sprintf(name, "0x%x-0x%x", dump_type, dump_id); 382 383 /* we may get notified twice, let's handle 384 * that gracefully and not create two conflicting 385 * entries. 386 */ 387 kobj = kset_find_obj(dump_kset, name); 388 if (kobj) { 389 /* Drop reference added by kset_find_obj() */ 390 kobject_put(kobj); 391 return IRQ_HANDLED; 392 } 393 394 create_dump_obj(dump_id, dump_size, dump_type); 395 396 return IRQ_HANDLED; 397 } 398 399 void __init opal_platform_dump_init(void) 400 { 401 int rc; 402 int dump_irq; 403 404 /* ELOG not supported by firmware */ 405 if (!opal_check_token(OPAL_DUMP_READ)) 406 return; 407 408 dump_kset = kset_create_and_add("dump", NULL, opal_kobj); 409 if (!dump_kset) { 410 pr_warn("%s: Failed to create dump kset\n", __func__); 411 return; 412 } 413 414 rc = sysfs_create_group(&dump_kset->kobj, &initiate_attr_group); 415 if (rc) { 416 pr_warn("%s: Failed to create initiate dump attr group\n", 417 __func__); 418 kobject_put(&dump_kset->kobj); 419 return; 420 } 421 422 dump_irq = opal_event_request(ilog2(OPAL_EVENT_DUMP_AVAIL)); 423 if (!dump_irq) { 424 pr_err("%s: Can't register OPAL event irq (%d)\n", 425 __func__, dump_irq); 426 return; 427 } 428 429 rc = request_threaded_irq(dump_irq, NULL, process_dump, 430 IRQF_TRIGGER_HIGH | IRQF_ONESHOT, 431 "opal-dump", NULL); 432 if (rc) { 433 pr_err("%s: Can't request OPAL event irq (%d)\n", 434 __func__, rc); 435 return; 436 } 437 438 if (opal_check_token(OPAL_DUMP_RESEND)) 439 opal_dump_resend_notification(); 440 } 441