arch/powerpc/platforms/powernv/opal.c

   1 /*
   2  * PowerNV OPAL high level interfaces
   3  *
   4  * Copyright 2011 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 #define pr_fmt(fmt)     "opal: " fmt
  13
  14 #include <linux/printk.h>
  15 #include <linux/types.h>
  16 #include <linux/of.h>
  17 #include <linux/of_fdt.h>
  18 #include <linux/of_platform.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/notifier.h>
  21 #include <linux/slab.h>
  22 #include <linux/sched.h>
  23 #include <linux/kobject.h>
  24 #include <linux/delay.h>
  25 #include <linux/memblock.h>
  26 #include <linux/kthread.h>
  27 #include <linux/freezer.h>
  28
  29 #include <asm/machdep.h>
  30 #include <asm/opal.h>
  31 #include <asm/firmware.h>
  32 #include <asm/mce.h>
  33
  34 #include "powernv.h"
  35
  36 /* /sys/firmware/opal */
  37 struct kobject *opal_kobj;
  38
  39 struct opal {
  40         u64 base;
  41         u64 entry;
  42         u64 size;
  43 } opal;
  44
  45 struct mcheck_recoverable_range {
  46         u64 start_addr;
  47         u64 end_addr;
  48         u64 recover_addr;
  49 };
  50
  51 static struct mcheck_recoverable_range *mc_recoverable_range;
  52 static int mc_recoverable_range_len;
  53
  54 struct device_node *opal_node;
  55 static DEFINE_SPINLOCK(opal_write_lock);
  56 static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX];
  57 static uint32_t opal_heartbeat;
  58
  59 static void opal_reinit_cores(void)
  60 {
  61         /* Do the actual re-init, This will clobber all FPRs, VRs, etc...
  62          *
  63          * It will preserve non volatile GPRs and HSPRG0/1. It will
  64          * also restore HIDs and other SPRs to their original value
  65          * but it might clobber a bunch.
  66          */
  67 #ifdef __BIG_ENDIAN__
  68         opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_BE);
  69 #else
  70         opal_reinit_cpus(OPAL_REINIT_CPUS_HILE_LE);
  71 #endif
  72 }
  73
  74 int __init early_init_dt_scan_opal(unsigned long node,
  75                                    const char *uname, int depth, void *data)
  76 {
  77         const void *basep, *entryp, *sizep;
  78         int basesz, entrysz, runtimesz;
  79
  80         if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
  81                 return 0;
  82
  83         basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
  84         entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
  85         sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz);
  86
  87         if (!basep || !entryp || !sizep)
  88                 return 1;
  89
  90         opal.base = of_read_number(basep, basesz/4);
  91         opal.entry = of_read_number(entryp, entrysz/4);
  92         opal.size = of_read_number(sizep, runtimesz/4);
  93
  94         pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%d)\n",
  95                  opal.base, basep, basesz);
  96         pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%d)\n",
  97                  opal.entry, entryp, entrysz);
  98         pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%d)\n",
  99                  opal.size, sizep, runtimesz);
 100
 101         powerpc_firmware_features |= FW_FEATURE_OPAL;
 102         if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
 103                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
 104                 powerpc_firmware_features |= FW_FEATURE_OPALv3;
 105                 pr_info("OPAL V3 detected !\n");
 106         } else if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
 107                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
 108                 pr_info("OPAL V2 detected !\n");
 109         } else {
 110                 pr_info("OPAL V1 detected !\n");
 111         }
 112
 113         /* Reinit all cores with the right endian */
 114         opal_reinit_cores();
 115
 116         /* Restore some bits */
 117         if (cur_cpu_spec->cpu_restore)
 118                 cur_cpu_spec->cpu_restore();
 119
 120         return 1;
 121 }
 122
 123 int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
 124                                    const char *uname, int depth, void *data)
 125 {
 126         int i, psize, size;
 127         const __be32 *prop;
 128
 129         if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
 130                 return 0;
 131
 132         prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &psize);
 133
 134         if (!prop)
 135                 return 1;
 136
 137         pr_debug("Found machine check recoverable ranges.\n");
 138
 139         /*
 140          * Calculate number of available entries.
 141          *
 142          * Each recoverable address range entry is (start address, len,
 143          * recovery address), 2 cells each for start and recovery address,
 144          * 1 cell for len, totalling 5 cells per entry.
 145          */
 146         mc_recoverable_range_len = psize / (sizeof(*prop) * 5);
 147
 148         /* Sanity check */
 149         if (!mc_recoverable_range_len)
 150                 return 1;
 151
 152         /* Size required to hold all the entries. */
 153         size = mc_recoverable_range_len *
 154                         sizeof(struct mcheck_recoverable_range);
 155
 156         /*
 157          * Allocate a buffer to hold the MC recoverable ranges. We would be
 158          * accessing them in real mode, hence it needs to be within
 159          * RMO region.
 160          */
 161         mc_recoverable_range =__va(memblock_alloc_base(size, __alignof__(u64),
 162                                                         ppc64_rma_size));
 163         memset(mc_recoverable_range, 0, size);
 164
 165         for (i = 0; i < mc_recoverable_range_len; i++) {
 166                 mc_recoverable_range[i].start_addr =
 167                                         of_read_number(prop + (i * 5) + 0, 2);
 168                 mc_recoverable_range[i].end_addr =
 169                                         mc_recoverable_range[i].start_addr +
 170                                         of_read_number(prop + (i * 5) + 2, 1);
 171                 mc_recoverable_range[i].recover_addr =
 172                                         of_read_number(prop + (i * 5) + 3, 2);
 173
 174                 pr_debug("Machine check recoverable range: %llx..%llx: %llx\n",
 175                                 mc_recoverable_range[i].start_addr,
 176                                 mc_recoverable_range[i].end_addr,
 177                                 mc_recoverable_range[i].recover_addr);
 178         }
 179         return 1;
 180 }
 181
 182 static int __init opal_register_exception_handlers(void)
 183 {
 184 #ifdef __BIG_ENDIAN__
 185         u64 glue;
 186
 187         if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
 188                 return -ENODEV;
 189
 190         /* Hookup some exception handlers except machine check. We use the
 191          * fwnmi area at 0x7000 to provide the glue space to OPAL
 192          */
 193         glue = 0x7000;
 194
 195         /*
 196          * Check if we are running on newer firmware that exports
 197          * OPAL_HANDLE_HMI token. If yes, then don't ask OPAL to patch
 198          * the HMI interrupt and we catch it directly in Linux.
 199          *
 200          * For older firmware (i.e currently released POWER8 System Firmware
 201          * as of today <= SV810_087), we fallback to old behavior and let OPAL
 202          * patch the HMI vector and handle it inside OPAL firmware.
 203          *
 204          * For newer firmware (in development/yet to be released) we will
 205          * start catching/handling HMI directly in Linux.
 206          */
 207         if (!opal_check_token(OPAL_HANDLE_HMI)) {
 208                 pr_info("Old firmware detected, OPAL handles HMIs.\n");
 209                 opal_register_exception_handler(
 210                                 OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
 211                                 0, glue);
 212                 glue += 128;
 213         }
 214
 215         opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
 216 #endif
 217
 218         return 0;
 219 }
 220 machine_early_initcall(powernv, opal_register_exception_handlers);
 221
 222 /*
 223  * Opal message notifier based on message type. Allow subscribers to get
 224  * notified for specific messgae type.
 225  */
 226 int opal_message_notifier_register(enum opal_msg_type msg_type,
 227                                         struct notifier_block *nb)
 228 {
 229         if (!nb || msg_type >= OPAL_MSG_TYPE_MAX) {
 230                 pr_warning("%s: Invalid arguments, msg_type:%d\n",
 231                            __func__, msg_type);
 232                 return -EINVAL;
 233         }
 234
 235         return atomic_notifier_chain_register(
 236                                 &opal_msg_notifier_head[msg_type], nb);
 237 }
 238 EXPORT_SYMBOL_GPL(opal_message_notifier_register);
 239
 240 int opal_message_notifier_unregister(enum opal_msg_type msg_type,
 241                                      struct notifier_block *nb)
 242 {
 243         return atomic_notifier_chain_unregister(
 244                         &opal_msg_notifier_head[msg_type], nb);
 245 }
 246 EXPORT_SYMBOL_GPL(opal_message_notifier_unregister);
 247
 248 static void opal_message_do_notify(uint32_t msg_type, void *msg)
 249 {
 250         /* notify subscribers */
 251         atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
 252                                         msg_type, msg);
 253 }
 254
 255 static void opal_handle_message(void)
 256 {
 257         s64 ret;
 258         /*
 259          * TODO: pre-allocate a message buffer depending on opal-msg-size
 260          * value in /proc/device-tree.
 261          */
 262         static struct opal_msg msg;
 263         u32 type;
 264
 265         ret = opal_get_msg(__pa(&msg), sizeof(msg));
 266         /* No opal message pending. */
 267         if (ret == OPAL_RESOURCE)
 268                 return;
 269
 270         /* check for errors. */
 271         if (ret) {
 272                 pr_warning("%s: Failed to retrieve opal message, err=%lld\n",
 273                                 __func__, ret);
 274                 return;
 275         }
 276
 277         type = be32_to_cpu(msg.msg_type);
 278
 279         /* Sanity check */
 280         if (type >= OPAL_MSG_TYPE_MAX) {
 281                 pr_warning("%s: Unknown message type: %u\n", __func__, type);
 282                 return;
 283         }
 284         opal_message_do_notify(type, (void *)&msg);
 285 }
 286
 287 static irqreturn_t opal_message_notify(int irq, void *data)
 288 {
 289         opal_handle_message();
 290         return IRQ_HANDLED;
 291 }
 292
 293 static int __init opal_message_init(void)
 294 {
 295         int ret, i, irq;
 296
 297         for (i = 0; i < OPAL_MSG_TYPE_MAX; i++)
 298                 ATOMIC_INIT_NOTIFIER_HEAD(&opal_msg_notifier_head[i]);
 299
 300         irq = opal_event_request(ilog2(OPAL_EVENT_MSG_PENDING));
 301         if (!irq) {
 302                 pr_err("%s: Can't register OPAL event irq (%d)\n",
 303                        __func__, irq);
 304                 return irq;
 305         }
 306
 307         ret = request_irq(irq, opal_message_notify,
 308                         IRQ_TYPE_LEVEL_HIGH, "opal-msg", NULL);
 309         if (ret) {
 310                 pr_err("%s: Can't request OPAL event irq (%d)\n",
 311                        __func__, ret);
 312                 return ret;
 313         }
 314
 315         return 0;
 316 }
 317
 318 int opal_get_chars(uint32_t vtermno, char *buf, int count)
 319 {
 320         s64 rc;
 321         __be64 evt, len;
 322
 323         if (!opal.entry)
 324                 return -ENODEV;
 325         opal_poll_events(&evt);
 326         if ((be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_INPUT) == 0)
 327                 return 0;
 328         len = cpu_to_be64(count);
 329         rc = opal_console_read(vtermno, &len, buf);
 330         if (rc == OPAL_SUCCESS)
 331                 return be64_to_cpu(len);
 332         return 0;
 333 }
 334
 335 int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
 336 {
 337         int written = 0;
 338         __be64 olen;
 339         s64 len, rc;
 340         unsigned long flags;
 341         __be64 evt;
 342
 343         if (!opal.entry)
 344                 return -ENODEV;
 345
 346         /* We want put_chars to be atomic to avoid mangling of hvsi
 347          * packets. To do that, we first test for room and return
 348          * -EAGAIN if there isn't enough.
 349          *
 350          * Unfortunately, opal_console_write_buffer_space() doesn't
 351          * appear to work on opal v1, so we just assume there is
 352          * enough room and be done with it
 353          */
 354         spin_lock_irqsave(&opal_write_lock, flags);
 355         if (firmware_has_feature(FW_FEATURE_OPALv2)) {
 356                 rc = opal_console_write_buffer_space(vtermno, &olen);
 357                 len = be64_to_cpu(olen);
 358                 if (rc || len < total_len) {
 359                         spin_unlock_irqrestore(&opal_write_lock, flags);
 360                         /* Closed -> drop characters */
 361                         if (rc)
 362                                 return total_len;
 363                         opal_poll_events(NULL);
 364                         return -EAGAIN;
 365                 }
 366         }
 367
 368         /* We still try to handle partial completions, though they
 369          * should no longer happen.
 370          */
 371         rc = OPAL_BUSY;
 372         while(total_len > 0 && (rc == OPAL_BUSY ||
 373                                 rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
 374                 olen = cpu_to_be64(total_len);
 375                 rc = opal_console_write(vtermno, &olen, data);
 376                 len = be64_to_cpu(olen);
 377
 378                 /* Closed or other error drop */
 379                 if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
 380                     rc != OPAL_BUSY_EVENT) {
 381                         written = total_len;
 382                         break;
 383                 }
 384                 if (rc == OPAL_SUCCESS) {
 385                         total_len -= len;
 386                         data += len;
 387                         written += len;
 388                 }
 389                 /* This is a bit nasty but we need that for the console to
 390                  * flush when there aren't any interrupts. We will clean
 391                  * things a bit later to limit that to synchronous path
 392                  * such as the kernel console and xmon/udbg
 393                  */
 394                 do
 395                         opal_poll_events(&evt);
 396                 while(rc == OPAL_SUCCESS &&
 397                         (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT));
 398         }
 399         spin_unlock_irqrestore(&opal_write_lock, flags);
 400         return written;
 401 }
 402
 403 static int opal_recover_mce(struct pt_regs *regs,
 404                                         struct machine_check_event *evt)
 405 {
 406         int recovered = 0;
 407         uint64_t ea = get_mce_fault_addr(evt);
 408
 409         if (!(regs->msr & MSR_RI)) {
 410                 /* If MSR_RI isn't set, we cannot recover */
 411                 recovered = 0;
 412         } else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
 413                 /* Platform corrected itself */
 414                 recovered = 1;
 415         } else if (ea && !is_kernel_addr(ea)) {
 416                 /*
 417                  * Faulting address is not in kernel text. We should be fine.
 418                  * We need to find which process uses this address.
 419                  * For now, kill the task if we have received exception when
 420                  * in userspace.
 421                  *
 422                  * TODO: Queue up this address for hwpoisioning later.
 423                  */
 424                 if (user_mode(regs) && !is_global_init(current)) {
 425                         _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
 426                         recovered = 1;
 427                 } else
 428                         recovered = 0;
 429         } else if (user_mode(regs) && !is_global_init(current) &&
 430                 evt->severity == MCE_SEV_ERROR_SYNC) {
 431                 /*
 432                  * If we have received a synchronous error when in userspace
 433                  * kill the task.
 434                  */
 435                 _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
 436                 recovered = 1;
 437         }
 438         return recovered;
 439 }
 440
 441 int opal_machine_check(struct pt_regs *regs)
 442 {
 443         struct machine_check_event evt;
 444         int ret;
 445
 446         if (!get_mce_event(&evt, MCE_EVENT_RELEASE))
 447                 return 0;
 448
 449         /* Print things out */
 450         if (evt.version != MCE_V1) {
 451                 pr_err("Machine Check Exception, Unknown event version %d !\n",
 452                        evt.version);
 453                 return 0;
 454         }
 455         machine_check_print_event_info(&evt);
 456
 457         if (opal_recover_mce(regs, &evt))
 458                 return 1;
 459
 460         /*
 461          * Unrecovered machine check, we are heading to panic path.
 462          *
 463          * We may have hit this MCE in very early stage of kernel
 464          * initialization even before opal-prd has started running. If
 465          * this is the case then this MCE error may go un-noticed or
 466          * un-analyzed if we go down panic path. We need to inform
 467          * BMC/OCC about this error so that they can collect relevant
 468          * data for error analysis before rebooting.
 469          * Use opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR) to do so.
 470          * This function may not return on BMC based system.
 471          */
 472         ret = opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR,
 473                         "Unrecoverable Machine Check exception");
 474         if (ret == OPAL_UNSUPPORTED) {
 475                 pr_emerg("Reboot type %d not supported\n",
 476                                         OPAL_REBOOT_PLATFORM_ERROR);
 477         }
 478
 479         /*
 480          * We reached here. There can be three possibilities:
 481          * 1. We are running on a firmware level that do not support
 482          *    opal_cec_reboot2()
 483          * 2. We are running on a firmware level that do not support
 484          *    OPAL_REBOOT_PLATFORM_ERROR reboot type.
 485          * 3. We are running on FSP based system that does not need opal
 486          *    to trigger checkstop explicitly for error analysis. The FSP
 487          *    PRD component would have already got notified about this
 488          *    error through other channels.
 489          *
 490          * If hardware marked this as an unrecoverable MCE, we are
 491          * going to panic anyway. Even if it didn't, it's not safe to
 492          * continue at this point, so we should explicitly panic.
 493          */
 494
 495         panic("PowerNV Unrecovered Machine Check");
 496         return 0;
 497 }
 498
 499 /* Early hmi handler called in real mode. */
 500 int opal_hmi_exception_early(struct pt_regs *regs)
 501 {
 502         s64 rc;
 503
 504         /*
 505          * call opal hmi handler. Pass paca address as token.
 506          * The return value OPAL_SUCCESS is an indication that there is
 507          * an HMI event generated waiting to pull by Linux.
 508          */
 509         rc = opal_handle_hmi();
 510         if (rc == OPAL_SUCCESS) {
 511                 local_paca->hmi_event_available = 1;
 512                 return 1;
 513         }
 514         return 0;
 515 }
 516
 517 /* HMI exception handler called in virtual mode during check_irq_replay. */
 518 int opal_handle_hmi_exception(struct pt_regs *regs)
 519 {
 520         s64 rc;
 521         __be64 evt = 0;
 522
 523         /*
 524          * Check if HMI event is available.
 525          * if Yes, then call opal_poll_events to pull opal messages and
 526          * process them.
 527          */
 528         if (!local_paca->hmi_event_available)
 529                 return 0;
 530
 531         local_paca->hmi_event_available = 0;
 532         rc = opal_poll_events(&evt);
 533         if (rc == OPAL_SUCCESS && evt)
 534                 opal_handle_events(be64_to_cpu(evt));
 535
 536         return 1;
 537 }
 538
 539 static uint64_t find_recovery_address(uint64_t nip)
 540 {
 541         int i;
 542
 543         for (i = 0; i < mc_recoverable_range_len; i++)
 544                 if ((nip >= mc_recoverable_range[i].start_addr) &&
 545                     (nip < mc_recoverable_range[i].end_addr))
 546                     return mc_recoverable_range[i].recover_addr;
 547         return 0;
 548 }
 549
 550 bool opal_mce_check_early_recovery(struct pt_regs *regs)
 551 {
 552         uint64_t recover_addr = 0;
 553
 554         if (!opal.base || !opal.size)
 555                 goto out;
 556
 557         if ((regs->nip >= opal.base) &&
 558                         (regs->nip <= (opal.base + opal.size)))
 559                 recover_addr = find_recovery_address(regs->nip);
 560
 561         /*
 562          * Setup regs->nip to rfi into fixup address.
 563          */
 564         if (recover_addr)
 565                 regs->nip = recover_addr;
 566
 567 out:
 568         return !!recover_addr;
 569 }
 570
 571 static int opal_sysfs_init(void)
 572 {
 573         opal_kobj = kobject_create_and_add("opal", firmware_kobj);
 574         if (!opal_kobj) {
 575                 pr_warn("kobject_create_and_add opal failed\n");
 576                 return -ENOMEM;
 577         }
 578
 579         return 0;
 580 }
 581
 582 static ssize_t symbol_map_read(struct file *fp, struct kobject *kobj,
 583                                struct bin_attribute *bin_attr,
 584                                char *buf, loff_t off, size_t count)
 585 {
 586         return memory_read_from_buffer(buf, count, &off, bin_attr->private,
 587                                        bin_attr->size);
 588 }
 589
 590 static BIN_ATTR_RO(symbol_map, 0);
 591
 592 static void opal_export_symmap(void)
 593 {
 594         const __be64 *syms;
 595         unsigned int size;
 596         struct device_node *fw;
 597         int rc;
 598
 599         fw = of_find_node_by_path("/ibm,opal/firmware");
 600         if (!fw)
 601                 return;
 602         syms = of_get_property(fw, "symbol-map", &size);
 603         if (!syms || size != 2 * sizeof(__be64))
 604                 return;
 605
 606         /* Setup attributes */
 607         bin_attr_symbol_map.private = __va(be64_to_cpu(syms[0]));
 608         bin_attr_symbol_map.size = be64_to_cpu(syms[1]);
 609
 610         rc = sysfs_create_bin_file(opal_kobj, &bin_attr_symbol_map);
 611         if (rc)
 612                 pr_warn("Error %d creating OPAL symbols file\n", rc);
 613 }
 614
 615 static void __init opal_dump_region_init(void)
 616 {
 617         void *addr;
 618         uint64_t size;
 619         int rc;
 620
 621         if (!opal_check_token(OPAL_REGISTER_DUMP_REGION))
 622                 return;
 623
 624         /* Register kernel log buffer */
 625         addr = log_buf_addr_get();
 626         if (addr == NULL)
 627                 return;
 628
 629         size = log_buf_len_get();
 630         if (size == 0)
 631                 return;
 632
 633         rc = opal_register_dump_region(OPAL_DUMP_REGION_LOG_BUF,
 634                                        __pa(addr), size);
 635         /* Don't warn if this is just an older OPAL that doesn't
 636          * know about that call
 637          */
 638         if (rc && rc != OPAL_UNSUPPORTED)
 639                 pr_warn("DUMP: Failed to register kernel log buffer. "
 640                         "rc = %d\n", rc);
 641 }
 642
 643 static void opal_pdev_init(struct device_node *opal_node,
 644                 const char *compatible)
 645 {
 646         struct device_node *np;
 647
 648         for_each_child_of_node(opal_node, np)
 649                 if (of_device_is_compatible(np, compatible))
 650                         of_platform_device_create(np, NULL, NULL);
 651 }
 652
 653 static void opal_i2c_create_devs(void)
 654 {
 655         struct device_node *np;
 656
 657         for_each_compatible_node(np, NULL, "ibm,opal-i2c")
 658                 of_platform_device_create(np, NULL, NULL);
 659 }
 660
 661 static int kopald(void *unused)
 662 {
 663         __be64 events;
 664
 665         set_freezable();
 666         do {
 667                 try_to_freeze();
 668                 opal_poll_events(&events);
 669                 opal_handle_events(be64_to_cpu(events));
 670                 msleep_interruptible(opal_heartbeat);
 671         } while (!kthread_should_stop());
 672
 673         return 0;
 674 }
 675
 676 static void opal_init_heartbeat(void)
 677 {
 678         /* Old firwmware, we assume the HVC heartbeat is sufficient */
 679         if (of_property_read_u32(opal_node, "ibm,heartbeat-ms",
 680                                  &opal_heartbeat) != 0)
 681                 opal_heartbeat = 0;
 682
 683         if (opal_heartbeat)
 684                 kthread_run(kopald, NULL, "kopald");
 685 }
 686
 687 static int __init opal_init(void)
 688 {
 689         struct device_node *np, *consoles, *leds;
 690         int rc;
 691
 692         opal_node = of_find_node_by_path("/ibm,opal");
 693         if (!opal_node) {
 694                 pr_warn("Device node not found\n");
 695                 return -ENODEV;
 696         }
 697
 698         /* Register OPAL consoles if any ports */
 699         if (firmware_has_feature(FW_FEATURE_OPALv2))
 700                 consoles = of_find_node_by_path("/ibm,opal/consoles");
 701         else
 702                 consoles = of_node_get(opal_node);
 703         if (consoles) {
 704                 for_each_child_of_node(consoles, np) {
 705                         if (strcmp(np->name, "serial"))
 706                                 continue;
 707                         of_platform_device_create(np, NULL, NULL);
 708                 }
 709                 of_node_put(consoles);
 710         }
 711
 712         /* Initialise OPAL messaging system */
 713         opal_message_init();
 714
 715         /* Initialise OPAL asynchronous completion interface */
 716         opal_async_comp_init();
 717
 718         /* Initialise OPAL sensor interface */
 719         opal_sensor_init();
 720
 721         /* Initialise OPAL hypervisor maintainence interrupt handling */
 722         opal_hmi_handler_init();
 723
 724         /* Create i2c platform devices */
 725         opal_i2c_create_devs();
 726
 727         /* Setup a heatbeat thread if requested by OPAL */
 728         opal_init_heartbeat();
 729
 730         /* Create leds platform devices */
 731         leds = of_find_node_by_path("/ibm,opal/leds");
 732         if (leds) {
 733                 of_platform_device_create(leds, "opal_leds", NULL);
 734                 of_node_put(leds);
 735         }
 736
 737         /* Create "opal" kobject under /sys/firmware */
 738         rc = opal_sysfs_init();
 739         if (rc == 0) {
 740                 /* Export symbol map to userspace */
 741                 opal_export_symmap();
 742                 /* Setup dump region interface */
 743                 opal_dump_region_init();
 744                 /* Setup error log interface */
 745                 rc = opal_elog_init();
 746                 /* Setup code update interface */
 747                 opal_flash_update_init();
 748                 /* Setup platform dump extract interface */
 749                 opal_platform_dump_init();
 750                 /* Setup system parameters interface */
 751                 opal_sys_param_init();
 752                 /* Setup message log interface. */
 753                 opal_msglog_init();
 754         }
 755
 756         /* Initialize platform devices: IPMI backend, PRD & flash interface */
 757         opal_pdev_init(opal_node, "ibm,opal-ipmi");
 758         opal_pdev_init(opal_node, "ibm,opal-flash");
 759         opal_pdev_init(opal_node, "ibm,opal-prd");
 760
 761         return 0;
 762 }
 763 machine_subsys_initcall(powernv, opal_init);
 764
 765 void opal_shutdown(void)
 766 {
 767         long rc = OPAL_BUSY;
 768
 769         opal_event_shutdown();
 770
 771         /*
 772          * Then sync with OPAL which ensure anything that can
 773          * potentially write to our memory has completed such
 774          * as an ongoing dump retrieval
 775          */
 776         while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
 777                 rc = opal_sync_host_reboot();
 778                 if (rc == OPAL_BUSY)
 779                         opal_poll_events(NULL);
 780                 else
 781                         mdelay(10);
 782         }
 783
 784         /* Unregister memory dump region */
 785         if (opal_check_token(OPAL_UNREGISTER_DUMP_REGION))
 786                 opal_unregister_dump_region(OPAL_DUMP_REGION_LOG_BUF);
 787 }
 788
 789 /* Export this so that test modules can use it */
 790 EXPORT_SYMBOL_GPL(opal_invalid_call);
 791 EXPORT_SYMBOL_GPL(opal_xscom_read);
 792 EXPORT_SYMBOL_GPL(opal_xscom_write);
 793 EXPORT_SYMBOL_GPL(opal_ipmi_send);
 794 EXPORT_SYMBOL_GPL(opal_ipmi_recv);
 795 EXPORT_SYMBOL_GPL(opal_flash_read);
 796 EXPORT_SYMBOL_GPL(opal_flash_write);
 797 EXPORT_SYMBOL_GPL(opal_flash_erase);
 798 EXPORT_SYMBOL_GPL(opal_prd_msg);
 799
 800 /* Convert a region of vmalloc memory to an opal sg list */
 801 struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
 802                                              unsigned long vmalloc_size)
 803 {
 804         struct opal_sg_list *sg, *first = NULL;
 805         unsigned long i = 0;
 806
 807         sg = kzalloc(PAGE_SIZE, GFP_KERNEL);
 808         if (!sg)
 809                 goto nomem;
 810
 811         first = sg;
 812
 813         while (vmalloc_size > 0) {
 814                 uint64_t data = vmalloc_to_pfn(vmalloc_addr) << PAGE_SHIFT;
 815                 uint64_t length = min(vmalloc_size, PAGE_SIZE);
 816
 817                 sg->entry[i].data = cpu_to_be64(data);
 818                 sg->entry[i].length = cpu_to_be64(length);
 819                 i++;
 820
 821                 if (i >= SG_ENTRIES_PER_NODE) {
 822                         struct opal_sg_list *next;
 823
 824                         next = kzalloc(PAGE_SIZE, GFP_KERNEL);
 825                         if (!next)
 826                                 goto nomem;
 827
 828                         sg->length = cpu_to_be64(
 829                                         i * sizeof(struct opal_sg_entry) + 16);
 830                         i = 0;
 831                         sg->next = cpu_to_be64(__pa(next));
 832                         sg = next;
 833                 }
 834
 835                 vmalloc_addr += length;
 836                 vmalloc_size -= length;
 837         }
 838
 839         sg->length = cpu_to_be64(i * sizeof(struct opal_sg_entry) + 16);
 840
 841         return first;
 842
 843 nomem:
 844         pr_err("%s : Failed to allocate memory\n", __func__);
 845         opal_free_sg_list(first);
 846         return NULL;
 847 }
 848
 849 void opal_free_sg_list(struct opal_sg_list *sg)
 850 {
 851         while (sg) {
 852                 uint64_t next = be64_to_cpu(sg->next);
 853
 854                 kfree(sg);
 855
 856                 if (next)
 857                         sg = __va(next);
 858                 else
 859                         sg = NULL;
 860         }
 861 }
 862
 863 int opal_error_code(int rc)
 864 {
 865         switch (rc) {
 866         case OPAL_SUCCESS:              return 0;
 867
 868         case OPAL_PARAMETER:            return -EINVAL;
 869         case OPAL_ASYNC_COMPLETION:     return -EINPROGRESS;
 870         case OPAL_BUSY_EVENT:           return -EBUSY;
 871         case OPAL_NO_MEM:               return -ENOMEM;
 872         case OPAL_PERMISSION:           return -EPERM;
 873
 874         case OPAL_UNSUPPORTED:          return -EIO;
 875         case OPAL_HARDWARE:             return -EIO;
 876         case OPAL_INTERNAL_ERROR:       return -EIO;
 877         default:
 878                 pr_err("%s: unexpected OPAL error %d\n", __func__, rc);
 879                 return -EIO;
 880         }
 881 }
 882
 883 EXPORT_SYMBOL_GPL(opal_poll_events);
 884 EXPORT_SYMBOL_GPL(opal_rtc_read);
 885 EXPORT_SYMBOL_GPL(opal_rtc_write);
 886 EXPORT_SYMBOL_GPL(opal_tpo_read);
 887 EXPORT_SYMBOL_GPL(opal_tpo_write);
 888 EXPORT_SYMBOL_GPL(opal_i2c_request);
 889 /* Export these symbols for PowerNV LED class driver */
 890 EXPORT_SYMBOL_GPL(opal_leds_get_ind);
 891 EXPORT_SYMBOL_GPL(opal_leds_set_ind);