arch/powerpc/kernel/rtasd.c

   1 /*
   2  * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  *
   9  * Communication to userspace based on kernel/printk.c
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/errno.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/poll.h>
  17 #include <linux/proc_fs.h>
  18 #include <linux/init.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/cpu.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/slab.h>
  24
  25 #include <linux/uaccess.h>
  26 #include <asm/io.h>
  27 #include <asm/rtas.h>
  28 #include <asm/prom.h>
  29 #include <asm/nvram.h>
  30 #include <linux/atomic.h>
  31 #include <asm/machdep.h>
  32 #include <asm/topology.h>
  33
  34
  35 static DEFINE_SPINLOCK(rtasd_log_lock);
  36
  37 static DECLARE_WAIT_QUEUE_HEAD(rtas_log_wait);
  38
  39 static char *rtas_log_buf;
  40 static unsigned long rtas_log_start;
  41 static unsigned long rtas_log_size;
  42
  43 static int surveillance_timeout = -1;
  44
  45 static unsigned int rtas_error_log_max;
  46 static unsigned int rtas_error_log_buffer_max;
  47
  48 /* RTAS service tokens */
  49 static unsigned int event_scan;
  50 static unsigned int rtas_event_scan_rate;
  51
  52 static bool full_rtas_msgs;
  53
  54 /* Stop logging to nvram after first fatal error */
  55 static int logging_enabled; /* Until we initialize everything,
  56                              * make sure we don't try logging
  57                              * anything */
  58 static int error_log_cnt;
  59
  60 /*
  61  * Since we use 32 bit RTAS, the physical address of this must be below
  62  * 4G or else bad things happen. Allocate this in the kernel data and
  63  * make it big enough.
  64  */
  65 static unsigned char logdata[RTAS_ERROR_LOG_MAX];
  66
  67 static char *rtas_type[] = {
  68         "Unknown", "Retry", "TCE Error", "Internal Device Failure",
  69         "Timeout", "Data Parity", "Address Parity", "Cache Parity",
  70         "Address Invalid", "ECC Uncorrected", "ECC Corrupted",
  71 };
  72
  73 static char *rtas_event_type(int type)
  74 {
  75         if ((type > 0) && (type < 11))
  76                 return rtas_type[type];
  77
  78         switch (type) {
  79                 case RTAS_TYPE_EPOW:
  80                         return "EPOW";
  81                 case RTAS_TYPE_PLATFORM:
  82                         return "Platform Error";
  83                 case RTAS_TYPE_IO:
  84                         return "I/O Event";
  85                 case RTAS_TYPE_INFO:
  86                         return "Platform Information Event";
  87                 case RTAS_TYPE_DEALLOC:
  88                         return "Resource Deallocation Event";
  89                 case RTAS_TYPE_DUMP:
  90                         return "Dump Notification Event";
  91                 case RTAS_TYPE_PRRN:
  92                         return "Platform Resource Reassignment Event";
  93         }
  94
  95         return rtas_type[0];
  96 }
  97
  98 /* To see this info, grep RTAS /var/log/messages and each entry
  99  * will be collected together with obvious begin/end.
 100  * There will be a unique identifier on the begin and end lines.
 101  * This will persist across reboots.
 102  *
 103  * format of error logs returned from RTAS:
 104  * bytes        (size)  : contents
 105  * --------------------------------------------------------
 106  * 0-7          (8)     : rtas_error_log
 107  * 8-47         (40)    : extended info
 108  * 48-51        (4)     : vendor id
 109  * 52-1023 (vendor specific) : location code and debug data
 110  */
 111 static void printk_log_rtas(char *buf, int len)
 112 {
 113
 114         int i,j,n = 0;
 115         int perline = 16;
 116         char buffer[64];
 117         char * str = "RTAS event";
 118
 119         if (full_rtas_msgs) {
 120                 printk(RTAS_DEBUG "%d -------- %s begin --------\n",
 121                        error_log_cnt, str);
 122
 123                 /*
 124                  * Print perline bytes on each line, each line will start
 125                  * with RTAS and a changing number, so syslogd will
 126                  * print lines that are otherwise the same.  Separate every
 127                  * 4 bytes with a space.
 128                  */
 129                 for (i = 0; i < len; i++) {
 130                         j = i % perline;
 131                         if (j == 0) {
 132                                 memset(buffer, 0, sizeof(buffer));
 133                                 n = sprintf(buffer, "RTAS %d:", i/perline);
 134                         }
 135
 136                         if ((i % 4) == 0)
 137                                 n += sprintf(buffer+n, " ");
 138
 139                         n += sprintf(buffer+n, "%02x", (unsigned char)buf[i]);
 140
 141                         if (j == (perline-1))
 142                                 printk(KERN_DEBUG "%s\n", buffer);
 143                 }
 144                 if ((i % perline) != 0)
 145                         printk(KERN_DEBUG "%s\n", buffer);
 146
 147                 printk(RTAS_DEBUG "%d -------- %s end ----------\n",
 148                        error_log_cnt, str);
 149         } else {
 150                 struct rtas_error_log *errlog = (struct rtas_error_log *)buf;
 151
 152                 printk(RTAS_DEBUG "event: %d, Type: %s, Severity: %d\n",
 153                        error_log_cnt, rtas_event_type(rtas_error_type(errlog)),
 154                        rtas_error_severity(errlog));
 155         }
 156 }
 157
 158 static int log_rtas_len(char * buf)
 159 {
 160         int len;
 161         struct rtas_error_log *err;
 162         uint32_t extended_log_length;
 163
 164         /* rtas fixed header */
 165         len = 8;
 166         err = (struct rtas_error_log *)buf;
 167         extended_log_length = rtas_error_extended_log_length(err);
 168         if (rtas_error_extended(err) && extended_log_length) {
 169
 170                 /* extended header */
 171                 len += extended_log_length;
 172         }
 173
 174         if (rtas_error_log_max == 0)
 175                 rtas_error_log_max = rtas_get_error_log_max();
 176
 177         if (len > rtas_error_log_max)
 178                 len = rtas_error_log_max;
 179
 180         return len;
 181 }
 182
 183 /*
 184  * First write to nvram, if fatal error, that is the only
 185  * place we log the info.  The error will be picked up
 186  * on the next reboot by rtasd.  If not fatal, run the
 187  * method for the type of error.  Currently, only RTAS
 188  * errors have methods implemented, but in the future
 189  * there might be a need to store data in nvram before a
 190  * call to panic().
 191  *
 192  * XXX We write to nvram periodically, to indicate error has
 193  * been written and sync'd, but there is a possibility
 194  * that if we don't shutdown correctly, a duplicate error
 195  * record will be created on next reboot.
 196  */
 197 void pSeries_log_error(char *buf, unsigned int err_type, int fatal)
 198 {
 199         unsigned long offset;
 200         unsigned long s;
 201         int len = 0;
 202
 203         pr_debug("rtasd: logging event\n");
 204         if (buf == NULL)
 205                 return;
 206
 207         spin_lock_irqsave(&rtasd_log_lock, s);
 208
 209         /* get length and increase count */
 210         switch (err_type & ERR_TYPE_MASK) {
 211         case ERR_TYPE_RTAS_LOG:
 212                 len = log_rtas_len(buf);
 213                 if (!(err_type & ERR_FLAG_BOOT))
 214                         error_log_cnt++;
 215                 break;
 216         case ERR_TYPE_KERNEL_PANIC:
 217         default:
 218                 WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
 219                 spin_unlock_irqrestore(&rtasd_log_lock, s);
 220                 return;
 221         }
 222
 223 #ifdef CONFIG_PPC64
 224         /* Write error to NVRAM */
 225         if (logging_enabled && !(err_type & ERR_FLAG_BOOT))
 226                 nvram_write_error_log(buf, len, err_type, error_log_cnt);
 227 #endif /* CONFIG_PPC64 */
 228
 229         /*
 230          * rtas errors can occur during boot, and we do want to capture
 231          * those somewhere, even if nvram isn't ready (why not?), and even
 232          * if rtasd isn't ready. Put them into the boot log, at least.
 233          */
 234         if ((err_type & ERR_TYPE_MASK) == ERR_TYPE_RTAS_LOG)
 235                 printk_log_rtas(buf, len);
 236
 237         /* Check to see if we need to or have stopped logging */
 238         if (fatal || !logging_enabled) {
 239                 logging_enabled = 0;
 240                 WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
 241                 spin_unlock_irqrestore(&rtasd_log_lock, s);
 242                 return;
 243         }
 244
 245         /* call type specific method for error */
 246         switch (err_type & ERR_TYPE_MASK) {
 247         case ERR_TYPE_RTAS_LOG:
 248                 offset = rtas_error_log_buffer_max *
 249                         ((rtas_log_start+rtas_log_size) & LOG_NUMBER_MASK);
 250
 251                 /* First copy over sequence number */
 252                 memcpy(&rtas_log_buf[offset], (void *) &error_log_cnt, sizeof(int));
 253
 254                 /* Second copy over error log data */
 255                 offset += sizeof(int);
 256                 memcpy(&rtas_log_buf[offset], buf, len);
 257
 258                 if (rtas_log_size < LOG_NUMBER)
 259                         rtas_log_size += 1;
 260                 else
 261                         rtas_log_start += 1;
 262
 263                 WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
 264                 spin_unlock_irqrestore(&rtasd_log_lock, s);
 265                 wake_up_interruptible(&rtas_log_wait);
 266                 break;
 267         case ERR_TYPE_KERNEL_PANIC:
 268         default:
 269                 WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
 270                 spin_unlock_irqrestore(&rtasd_log_lock, s);
 271                 return;
 272         }
 273 }
 274
 275 #ifdef CONFIG_PPC_PSERIES
 276 static s32 prrn_update_scope;
 277
 278 static void prrn_work_fn(struct work_struct *work)
 279 {
 280         /*
 281          * For PRRN, we must pass the negative of the scope value in
 282          * the RTAS event.
 283          */
 284         pseries_devicetree_update(-prrn_update_scope);
 285 }
 286
 287 static DECLARE_WORK(prrn_work, prrn_work_fn);
 288
 289 static void prrn_schedule_update(u32 scope)
 290 {
 291         flush_work(&prrn_work);
 292         prrn_update_scope = scope;
 293         schedule_work(&prrn_work);
 294 }
 295
 296 static void handle_rtas_event(const struct rtas_error_log *log)
 297 {
 298         if (rtas_error_type(log) != RTAS_TYPE_PRRN || !prrn_is_enabled())
 299                 return;
 300
 301         /* For PRRN Events the extended log length is used to denote
 302          * the scope for calling rtas update-nodes.
 303          */
 304         prrn_schedule_update(rtas_error_extended_log_length(log));
 305 }
 306
 307 #else
 308
 309 static void handle_rtas_event(const struct rtas_error_log *log)
 310 {
 311         return;
 312 }
 313
 314 #endif
 315
 316 static int rtas_log_open(struct inode * inode, struct file * file)
 317 {
 318         return 0;
 319 }
 320
 321 static int rtas_log_release(struct inode * inode, struct file * file)
 322 {
 323         return 0;
 324 }
 325
 326 /* This will check if all events are logged, if they are then, we
 327  * know that we can safely clear the events in NVRAM.
 328  * Next we'll sit and wait for something else to log.
 329  */
 330 static ssize_t rtas_log_read(struct file * file, char __user * buf,
 331                          size_t count, loff_t *ppos)
 332 {
 333         int error;
 334         char *tmp;
 335         unsigned long s;
 336         unsigned long offset;
 337
 338         if (!buf || count < rtas_error_log_buffer_max)
 339                 return -EINVAL;
 340
 341         count = rtas_error_log_buffer_max;
 342
 343         if (!access_ok(VERIFY_WRITE, buf, count))
 344                 return -EFAULT;
 345
 346         tmp = kmalloc(count, GFP_KERNEL);
 347         if (!tmp)
 348                 return -ENOMEM;
 349
 350         spin_lock_irqsave(&rtasd_log_lock, s);
 351
 352         /* if it's 0, then we know we got the last one (the one in NVRAM) */
 353         while (rtas_log_size == 0) {
 354                 if (file->f_flags & O_NONBLOCK) {
 355                         spin_unlock_irqrestore(&rtasd_log_lock, s);
 356                         error = -EAGAIN;
 357                         goto out;
 358                 }
 359
 360                 if (!logging_enabled) {
 361                         spin_unlock_irqrestore(&rtasd_log_lock, s);
 362                         error = -ENODATA;
 363                         goto out;
 364                 }
 365 #ifdef CONFIG_PPC64
 366                 nvram_clear_error_log();
 367 #endif /* CONFIG_PPC64 */
 368
 369                 spin_unlock_irqrestore(&rtasd_log_lock, s);
 370                 error = wait_event_interruptible(rtas_log_wait, rtas_log_size);
 371                 if (error)
 372                         goto out;
 373                 spin_lock_irqsave(&rtasd_log_lock, s);
 374         }
 375
 376         offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK);
 377         memcpy(tmp, &rtas_log_buf[offset], count);
 378
 379         rtas_log_start += 1;
 380         rtas_log_size -= 1;
 381         spin_unlock_irqrestore(&rtasd_log_lock, s);
 382
 383         error = copy_to_user(buf, tmp, count) ? -EFAULT : count;
 384 out:
 385         kfree(tmp);
 386         return error;
 387 }
 388
 389 static unsigned int rtas_log_poll(struct file *file, poll_table * wait)
 390 {
 391         poll_wait(file, &rtas_log_wait, wait);
 392         if (rtas_log_size)
 393                 return POLLIN | POLLRDNORM;
 394         return 0;
 395 }
 396
 397 static const struct file_operations proc_rtas_log_operations = {
 398         .read =         rtas_log_read,
 399         .poll =         rtas_log_poll,
 400         .open =         rtas_log_open,
 401         .release =      rtas_log_release,
 402         .llseek =       noop_llseek,
 403 };
 404
 405 static int enable_surveillance(int timeout)
 406 {
 407         int error;
 408
 409         error = rtas_set_indicator(SURVEILLANCE_TOKEN, 0, timeout);
 410
 411         if (error == 0)
 412                 return 0;
 413
 414         if (error == -EINVAL) {
 415                 printk(KERN_DEBUG "rtasd: surveillance not supported\n");
 416                 return 0;
 417         }
 418
 419         printk(KERN_ERR "rtasd: could not update surveillance\n");
 420         return -1;
 421 }
 422
 423 static void do_event_scan(void)
 424 {
 425         int error;
 426         do {
 427                 memset(logdata, 0, rtas_error_log_max);
 428                 error = rtas_call(event_scan, 4, 1, NULL,
 429                                   RTAS_EVENT_SCAN_ALL_EVENTS, 0,
 430                                   __pa(logdata), rtas_error_log_max);
 431                 if (error == -1) {
 432                         printk(KERN_ERR "event-scan failed\n");
 433                         break;
 434                 }
 435
 436                 if (error == 0) {
 437                         pSeries_log_error(logdata, ERR_TYPE_RTAS_LOG, 0);
 438                         handle_rtas_event((struct rtas_error_log *)logdata);
 439                 }
 440
 441         } while(error == 0);
 442 }
 443
 444 static void rtas_event_scan(struct work_struct *w);
 445 static DECLARE_DELAYED_WORK(event_scan_work, rtas_event_scan);
 446
 447 /*
 448  * Delay should be at least one second since some machines have problems if
 449  * we call event-scan too quickly.
 450  */
 451 static unsigned long event_scan_delay = 1*HZ;
 452 static int first_pass = 1;
 453
 454 static void rtas_event_scan(struct work_struct *w)
 455 {
 456         unsigned int cpu;
 457
 458         do_event_scan();
 459
 460         get_online_cpus();
 461
 462         /* raw_ OK because just using CPU as starting point. */
 463         cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
 464         if (cpu >= nr_cpu_ids) {
 465                 cpu = cpumask_first(cpu_online_mask);
 466
 467                 if (first_pass) {
 468                         first_pass = 0;
 469                         event_scan_delay = 30*HZ/rtas_event_scan_rate;
 470
 471                         if (surveillance_timeout != -1) {
 472                                 pr_debug("rtasd: enabling surveillance\n");
 473                                 enable_surveillance(surveillance_timeout);
 474                                 pr_debug("rtasd: surveillance enabled\n");
 475                         }
 476                 }
 477         }
 478
 479         schedule_delayed_work_on(cpu, &event_scan_work,
 480                 __round_jiffies_relative(event_scan_delay, cpu));
 481
 482         put_online_cpus();
 483 }
 484
 485 #ifdef CONFIG_PPC64
 486 static void retrieve_nvram_error_log(void)
 487 {
 488         unsigned int err_type ;
 489         int rc ;
 490
 491         /* See if we have any error stored in NVRAM */
 492         memset(logdata, 0, rtas_error_log_max);
 493         rc = nvram_read_error_log(logdata, rtas_error_log_max,
 494                                   &err_type, &error_log_cnt);
 495         /* We can use rtas_log_buf now */
 496         logging_enabled = 1;
 497         if (!rc) {
 498                 if (err_type != ERR_FLAG_ALREADY_LOGGED) {
 499                         pSeries_log_error(logdata, err_type | ERR_FLAG_BOOT, 0);
 500                 }
 501         }
 502 }
 503 #else /* CONFIG_PPC64 */
 504 static void retrieve_nvram_error_log(void)
 505 {
 506 }
 507 #endif /* CONFIG_PPC64 */
 508
 509 static void start_event_scan(void)
 510 {
 511         printk(KERN_DEBUG "RTAS daemon started\n");
 512         pr_debug("rtasd: will sleep for %d milliseconds\n",
 513                  (30000 / rtas_event_scan_rate));
 514
 515         /* Retrieve errors from nvram if any */
 516         retrieve_nvram_error_log();
 517
 518         schedule_delayed_work_on(cpumask_first(cpu_online_mask),
 519                                  &event_scan_work, event_scan_delay);
 520 }
 521
 522 /* Cancel the rtas event scan work */
 523 void rtas_cancel_event_scan(void)
 524 {
 525         cancel_delayed_work_sync(&event_scan_work);
 526 }
 527 EXPORT_SYMBOL_GPL(rtas_cancel_event_scan);
 528
 529 static int __init rtas_event_scan_init(void)
 530 {
 531         if (!machine_is(pseries) && !machine_is(chrp))
 532                 return 0;
 533
 534         /* No RTAS */
 535         event_scan = rtas_token("event-scan");
 536         if (event_scan == RTAS_UNKNOWN_SERVICE) {
 537                 printk(KERN_INFO "rtasd: No event-scan on system\n");
 538                 return -ENODEV;
 539         }
 540
 541         rtas_event_scan_rate = rtas_token("rtas-event-scan-rate");
 542         if (rtas_event_scan_rate == RTAS_UNKNOWN_SERVICE) {
 543                 printk(KERN_ERR "rtasd: no rtas-event-scan-rate on system\n");
 544                 return -ENODEV;
 545         }
 546
 547         if (!rtas_event_scan_rate) {
 548                 /* Broken firmware: take a rate of zero to mean don't scan */
 549                 printk(KERN_DEBUG "rtasd: scan rate is 0, not scanning\n");
 550                 return 0;
 551         }
 552
 553         /* Make room for the sequence number */
 554         rtas_error_log_max = rtas_get_error_log_max();
 555         rtas_error_log_buffer_max = rtas_error_log_max + sizeof(int);
 556
 557         rtas_log_buf = vmalloc(rtas_error_log_buffer_max*LOG_NUMBER);
 558         if (!rtas_log_buf) {
 559                 printk(KERN_ERR "rtasd: no memory\n");
 560                 return -ENOMEM;
 561         }
 562
 563         start_event_scan();
 564
 565         return 0;
 566 }
 567 arch_initcall(rtas_event_scan_init);
 568
 569 static int __init rtas_init(void)
 570 {
 571         struct proc_dir_entry *entry;
 572
 573         if (!machine_is(pseries) && !machine_is(chrp))
 574                 return 0;
 575
 576         if (!rtas_log_buf)
 577                 return -ENODEV;
 578
 579         entry = proc_create("powerpc/rtas/error_log", S_IRUSR, NULL,
 580                             &proc_rtas_log_operations);
 581         if (!entry)
 582                 printk(KERN_ERR "Failed to create error_log proc entry\n");
 583
 584         return 0;
 585 }
 586 __initcall(rtas_init);
 587
 588 static int __init surveillance_setup(char *str)
 589 {
 590         int i;
 591
 592         /* We only do surveillance on pseries */
 593         if (!machine_is(pseries))
 594                 return 0;
 595
 596         if (get_option(&str,&i)) {
 597                 if (i >= 0 && i <= 255)
 598                         surveillance_timeout = i;
 599         }
 600
 601         return 1;
 602 }
 603 __setup("surveillance=", surveillance_setup);
 604
 605 static int __init rtasmsgs_setup(char *str)
 606 {
 607         return (kstrtobool(str, &full_rtas_msgs) == 0);
 608 }
 609 __setup("rtasmsgs=", rtasmsgs_setup);