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