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