arch/ia64/kernel/mca.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * File:        mca.c
   4  * Purpose:     Generic MCA handling layer
   5  *
   6  * Copyright (C) 2003 Hewlett-Packard Co
   7  *      David Mosberger-Tang <[email protected]>
   8  *
   9  * Copyright (C) 2002 Dell Inc.
  10  * Copyright (C) Matt Domsch <[email protected]>
  11  *
  12  * Copyright (C) 2002 Intel
  13  * Copyright (C) Jenna Hall <[email protected]>
  14  *
  15  * Copyright (C) 2001 Intel
  16  * Copyright (C) Fred Lewis <[email protected]>
  17  *
  18  * Copyright (C) 2000 Intel
  19  * Copyright (C) Chuck Fleckenstein <[email protected]>
  20  *
  21  * Copyright (C) 1999, 2004-2008 Silicon Graphics, Inc.
  22  * Copyright (C) Vijay Chander <[email protected]>
  23  *
  24  * Copyright (C) 2006 FUJITSU LIMITED
  25  * Copyright (C) Hidetoshi Seto <[email protected]>
  26  *
  27  * 2000-03-29 Chuck Fleckenstein <[email protected]>
  28  *            Fixed PAL/SAL update issues, began MCA bug fixes, logging issues,
  29  *            added min save state dump, added INIT handler.
  30  *
  31  * 2001-01-03 Fred Lewis <[email protected]>
  32  *            Added setup of CMCI and CPEI IRQs, logging of corrected platform
  33  *            errors, completed code for logging of corrected & uncorrected
  34  *            machine check errors, and updated for conformance with Nov. 2000
  35  *            revision of the SAL 3.0 spec.
  36  *
  37  * 2002-01-04 Jenna Hall <[email protected]>
  38  *            Aligned MCA stack to 16 bytes, added platform vs. CPU error flag,
  39  *            set SAL default return values, changed error record structure to
  40  *            linked list, added init call to sal_get_state_info_size().
  41  *
  42  * 2002-03-25 Matt Domsch <[email protected]>
  43  *            GUID cleanups.
  44  *
  45  * 2003-04-15 David Mosberger-Tang <[email protected]>
  46  *            Added INIT backtrace support.
  47  *
  48  * 2003-12-08 Keith Owens <[email protected]>
  49  *            smp_call_function() must not be called from interrupt context
  50  *            (can deadlock on tasklist_lock).
  51  *            Use keventd to call smp_call_function().
  52  *
  53  * 2004-02-01 Keith Owens <[email protected]>
  54  *            Avoid deadlock when using printk() for MCA and INIT records.
  55  *            Delete all record printing code, moved to salinfo_decode in user
  56  *            space.  Mark variables and functions static where possible.
  57  *            Delete dead variables and functions.  Reorder to remove the need
  58  *            for forward declarations and to consolidate related code.
  59  *
  60  * 2005-08-12 Keith Owens <[email protected]>
  61  *            Convert MCA/INIT handlers to use per event stacks and SAL/OS
  62  *            state.
  63  *
  64  * 2005-10-07 Keith Owens <[email protected]>
  65  *            Add notify_die() hooks.
  66  *
  67  * 2006-09-15 Hidetoshi Seto <[email protected]>
  68  *            Add printing support for MCA/INIT.
  69  *
  70  * 2007-04-27 Russ Anderson <[email protected]>
  71  *            Support multiple cpus going through OS_MCA in the same event.
  72  */
  73 #include <linux/jiffies.h>
  74 #include <linux/types.h>
  75 #include <linux/init.h>
  76 #include <linux/sched/signal.h>
  77 #include <linux/sched/debug.h>
  78 #include <linux/sched/task.h>
  79 #include <linux/interrupt.h>
  80 #include <linux/irq.h>
  81 #include <linux/memblock.h>
  82 #include <linux/acpi.h>
  83 #include <linux/timer.h>
  84 #include <linux/module.h>
  85 #include <linux/kernel.h>
  86 #include <linux/smp.h>
  87 #include <linux/workqueue.h>
  88 #include <linux/cpumask.h>
  89 #include <linux/kdebug.h>
  90 #include <linux/cpu.h>
  91 #include <linux/gfp.h>
  92
  93 #include <asm/delay.h>
  94 #include <asm/efi.h>
  95 #include <asm/meminit.h>
  96 #include <asm/page.h>
  97 #include <asm/ptrace.h>
  98 #include <asm/sal.h>
  99 #include <asm/mca.h>
 100 #include <asm/mca_asm.h>
 101 #include <asm/kexec.h>
 102
 103 #include <asm/irq.h>
 104 #include <asm/hw_irq.h>
 105 #include <asm/tlb.h>
 106
 107 #include "mca_drv.h"
 108 #include "entry.h"
 109 #include "irq.h"
 110
 111 #if defined(IA64_MCA_DEBUG_INFO)
 112 # define IA64_MCA_DEBUG(fmt...) printk(fmt)
 113 #else
 114 # define IA64_MCA_DEBUG(fmt...) do {} while (0)
 115 #endif
 116
 117 #define NOTIFY_INIT(event, regs, arg, spin)                             \
 118 do {                                                                    \
 119         if ((notify_die((event), "INIT", (regs), (arg), 0, 0)           \
 120                         == NOTIFY_STOP) && ((spin) == 1))               \
 121                 ia64_mca_spin(__func__);                                \
 122 } while (0)
 123
 124 #define NOTIFY_MCA(event, regs, arg, spin)                              \
 125 do {                                                                    \
 126         if ((notify_die((event), "MCA", (regs), (arg), 0, 0)            \
 127                         == NOTIFY_STOP) && ((spin) == 1))               \
 128                 ia64_mca_spin(__func__);                                \
 129 } while (0)
 130
 131 /* Used by mca_asm.S */
 132 DEFINE_PER_CPU(u64, ia64_mca_data); /* == __per_cpu_mca[smp_processor_id()] */
 133 DEFINE_PER_CPU(u64, ia64_mca_per_cpu_pte); /* PTE to map per-CPU area */
 134 DEFINE_PER_CPU(u64, ia64_mca_pal_pte);      /* PTE to map PAL code */
 135 DEFINE_PER_CPU(u64, ia64_mca_pal_base);    /* vaddr PAL code granule */
 136 DEFINE_PER_CPU(u64, ia64_mca_tr_reload);   /* Flag for TR reload */
 137
 138 unsigned long __per_cpu_mca[NR_CPUS];
 139
 140 /* In mca_asm.S */
 141 extern void                     ia64_os_init_dispatch_monarch (void);
 142 extern void                     ia64_os_init_dispatch_slave (void);
 143
 144 static int monarch_cpu = -1;
 145
 146 static ia64_mc_info_t           ia64_mc_info;
 147
 148 #define MAX_CPE_POLL_INTERVAL (15*60*HZ) /* 15 minutes */
 149 #define MIN_CPE_POLL_INTERVAL (2*60*HZ)  /* 2 minutes */
 150 #define CMC_POLL_INTERVAL     (1*60*HZ)  /* 1 minute */
 151 #define CPE_HISTORY_LENGTH    5
 152 #define CMC_HISTORY_LENGTH    5
 153
 154 static struct timer_list cpe_poll_timer;
 155 static struct timer_list cmc_poll_timer;
 156 /*
 157  * This variable tells whether we are currently in polling mode.
 158  * Start with this in the wrong state so we won't play w/ timers
 159  * before the system is ready.
 160  */
 161 static int cmc_polling_enabled = 1;
 162
 163 /*
 164  * Clearing this variable prevents CPE polling from getting activated
 165  * in mca_late_init.  Use it if your system doesn't provide a CPEI,
 166  * but encounters problems retrieving CPE logs.  This should only be
 167  * necessary for debugging.
 168  */
 169 static int cpe_poll_enabled = 1;
 170
 171 extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
 172
 173 static int mca_init __initdata;
 174
 175 /*
 176  * limited & delayed printing support for MCA/INIT handler
 177  */
 178
 179 #define mprintk(fmt...) ia64_mca_printk(fmt)
 180
 181 #define MLOGBUF_SIZE (512+256*NR_CPUS)
 182 #define MLOGBUF_MSGMAX 256
 183 static char mlogbuf[MLOGBUF_SIZE];
 184 static DEFINE_SPINLOCK(mlogbuf_wlock);  /* mca context only */
 185 static DEFINE_SPINLOCK(mlogbuf_rlock);  /* normal context only */
 186 static unsigned long mlogbuf_start;
 187 static unsigned long mlogbuf_end;
 188 static unsigned int mlogbuf_finished = 0;
 189 static unsigned long mlogbuf_timestamp = 0;
 190
 191 static int loglevel_save = -1;
 192 #define BREAK_LOGLEVEL(__console_loglevel)              \
 193         oops_in_progress = 1;                           \
 194         if (loglevel_save < 0)                          \
 195                 loglevel_save = __console_loglevel;     \
 196         __console_loglevel = 15;
 197
 198 #define RESTORE_LOGLEVEL(__console_loglevel)            \
 199         if (loglevel_save >= 0) {                       \
 200                 __console_loglevel = loglevel_save;     \
 201                 loglevel_save = -1;                     \
 202         }                                               \
 203         mlogbuf_finished = 0;                           \
 204         oops_in_progress = 0;
 205
 206 /*
 207  * Push messages into buffer, print them later if not urgent.
 208  */
 209 void ia64_mca_printk(const char *fmt, ...)
 210 {
 211         va_list args;
 212         int printed_len;
 213         char temp_buf[MLOGBUF_MSGMAX];
 214         char *p;
 215
 216         va_start(args, fmt);
 217         printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
 218         va_end(args);
 219
 220         /* Copy the output into mlogbuf */
 221         if (oops_in_progress) {
 222                 /* mlogbuf was abandoned, use printk directly instead. */
 223                 printk("%s", temp_buf);
 224         } else {
 225                 spin_lock(&mlogbuf_wlock);
 226                 for (p = temp_buf; *p; p++) {
 227                         unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
 228                         if (next != mlogbuf_start) {
 229                                 mlogbuf[mlogbuf_end] = *p;
 230                                 mlogbuf_end = next;
 231                         } else {
 232                                 /* buffer full */
 233                                 break;
 234                         }
 235                 }
 236                 mlogbuf[mlogbuf_end] = '\0';
 237                 spin_unlock(&mlogbuf_wlock);
 238         }
 239 }
 240 EXPORT_SYMBOL(ia64_mca_printk);
 241
 242 /*
 243  * Print buffered messages.
 244  *  NOTE: call this after returning normal context. (ex. from salinfod)
 245  */
 246 void ia64_mlogbuf_dump(void)
 247 {
 248         char temp_buf[MLOGBUF_MSGMAX];
 249         char *p;
 250         unsigned long index;
 251         unsigned long flags;
 252         unsigned int printed_len;
 253
 254         /* Get output from mlogbuf */
 255         while (mlogbuf_start != mlogbuf_end) {
 256                 temp_buf[0] = '\0';
 257                 p = temp_buf;
 258                 printed_len = 0;
 259
 260                 spin_lock_irqsave(&mlogbuf_rlock, flags);
 261
 262                 index = mlogbuf_start;
 263                 while (index != mlogbuf_end) {
 264                         *p = mlogbuf[index];
 265                         index = (index + 1) % MLOGBUF_SIZE;
 266                         if (!*p)
 267                                 break;
 268                         p++;
 269                         if (++printed_len >= MLOGBUF_MSGMAX - 1)
 270                                 break;
 271                 }
 272                 *p = '\0';
 273                 if (temp_buf[0])
 274                         printk("%s", temp_buf);
 275                 mlogbuf_start = index;
 276
 277                 mlogbuf_timestamp = 0;
 278                 spin_unlock_irqrestore(&mlogbuf_rlock, flags);
 279         }
 280 }
 281 EXPORT_SYMBOL(ia64_mlogbuf_dump);
 282
 283 /*
 284  * Call this if system is going to down or if immediate flushing messages to
 285  * console is required. (ex. recovery was failed, crash dump is going to be
 286  * invoked, long-wait rendezvous etc.)
 287  *  NOTE: this should be called from monarch.
 288  */
 289 static void ia64_mlogbuf_finish(int wait)
 290 {
 291         BREAK_LOGLEVEL(console_loglevel);
 292
 293         spin_lock_init(&mlogbuf_rlock);
 294         ia64_mlogbuf_dump();
 295         printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
 296                 "MCA/INIT might be dodgy or fail.\n");
 297
 298         if (!wait)
 299                 return;
 300
 301         /* wait for console */
 302         printk("Delaying for 5 seconds...\n");
 303         udelay(5*1000000);
 304
 305         mlogbuf_finished = 1;
 306 }
 307
 308 /*
 309  * Print buffered messages from INIT context.
 310  */
 311 static void ia64_mlogbuf_dump_from_init(void)
 312 {
 313         if (mlogbuf_finished)
 314                 return;
 315
 316         if (mlogbuf_timestamp &&
 317                         time_before(jiffies, mlogbuf_timestamp + 30 * HZ)) {
 318                 printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
 319                         " and the system seems to be messed up.\n");
 320                 ia64_mlogbuf_finish(0);
 321                 return;
 322         }
 323
 324         if (!spin_trylock(&mlogbuf_rlock)) {
 325                 printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
 326                         "Generated messages other than stack dump will be "
 327                         "buffered to mlogbuf and will be printed later.\n");
 328                 printk(KERN_ERR "INIT: If messages would not printed after "
 329                         "this INIT, wait 30sec and assert INIT again.\n");
 330                 if (!mlogbuf_timestamp)
 331                         mlogbuf_timestamp = jiffies;
 332                 return;
 333         }
 334         spin_unlock(&mlogbuf_rlock);
 335         ia64_mlogbuf_dump();
 336 }
 337
 338 static inline void
 339 ia64_mca_spin(const char *func)
 340 {
 341         if (monarch_cpu == smp_processor_id())
 342                 ia64_mlogbuf_finish(0);
 343         mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
 344         while (1)
 345                 cpu_relax();
 346 }
 347 /*
 348  * IA64_MCA log support
 349  */
 350 #define IA64_MAX_LOGS           2       /* Double-buffering for nested MCAs */
 351 #define IA64_MAX_LOG_TYPES      4   /* MCA, INIT, CMC, CPE */
 352
 353 typedef struct ia64_state_log_s
 354 {
 355         spinlock_t      isl_lock;
 356         int             isl_index;
 357         unsigned long   isl_count;
 358         ia64_err_rec_t  *isl_log[IA64_MAX_LOGS]; /* need space to store header + error log */
 359 } ia64_state_log_t;
 360
 361 static ia64_state_log_t ia64_state_log[IA64_MAX_LOG_TYPES];
 362
 363 #define IA64_LOG_LOCK_INIT(it) spin_lock_init(&ia64_state_log[it].isl_lock)
 364 #define IA64_LOG_LOCK(it)      spin_lock_irqsave(&ia64_state_log[it].isl_lock, s)
 365 #define IA64_LOG_UNLOCK(it)    spin_unlock_irqrestore(&ia64_state_log[it].isl_lock,s)
 366 #define IA64_LOG_NEXT_INDEX(it)    ia64_state_log[it].isl_index
 367 #define IA64_LOG_CURR_INDEX(it)    1 - ia64_state_log[it].isl_index
 368 #define IA64_LOG_INDEX_INC(it) \
 369     {ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index; \
 370     ia64_state_log[it].isl_count++;}
 371 #define IA64_LOG_INDEX_DEC(it) \
 372     ia64_state_log[it].isl_index = 1 - ia64_state_log[it].isl_index
 373 #define IA64_LOG_NEXT_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)]))
 374 #define IA64_LOG_CURR_BUFFER(it)   (void *)((ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)]))
 375 #define IA64_LOG_COUNT(it)         ia64_state_log[it].isl_count
 376
 377 static inline void ia64_log_allocate(int it, u64 size)
 378 {
 379         ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)] =
 380                 (ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
 381         if (!ia64_state_log[it].isl_log[IA64_LOG_CURR_INDEX(it)])
 382                 panic("%s: Failed to allocate %llu bytes\n", __func__, size);
 383
 384         ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)] =
 385                 (ia64_err_rec_t *)memblock_alloc(size, SMP_CACHE_BYTES);
 386         if (!ia64_state_log[it].isl_log[IA64_LOG_NEXT_INDEX(it)])
 387                 panic("%s: Failed to allocate %llu bytes\n", __func__, size);
 388 }
 389
 390 /*
 391  * ia64_log_init
 392  *      Reset the OS ia64 log buffer
 393  * Inputs   :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
 394  * Outputs      :       None
 395  */
 396 static void __init
 397 ia64_log_init(int sal_info_type)
 398 {
 399         u64     max_size = 0;
 400
 401         IA64_LOG_NEXT_INDEX(sal_info_type) = 0;
 402         IA64_LOG_LOCK_INIT(sal_info_type);
 403
 404         // SAL will tell us the maximum size of any error record of this type
 405         max_size = ia64_sal_get_state_info_size(sal_info_type);
 406         if (!max_size)
 407                 /* alloc_bootmem() doesn't like zero-sized allocations! */
 408                 return;
 409
 410         // set up OS data structures to hold error info
 411         ia64_log_allocate(sal_info_type, max_size);
 412 }
 413
 414 /*
 415  * ia64_log_get
 416  *
 417  *      Get the current MCA log from SAL and copy it into the OS log buffer.
 418  *
 419  *  Inputs  :   info_type   (SAL_INFO_TYPE_{MCA,INIT,CMC,CPE})
 420  *              irq_safe    whether you can use printk at this point
 421  *  Outputs :   size        (total record length)
 422  *              *buffer     (ptr to error record)
 423  *
 424  */
 425 static u64
 426 ia64_log_get(int sal_info_type, u8 **buffer, int irq_safe)
 427 {
 428         sal_log_record_header_t     *log_buffer;
 429         u64                         total_len = 0;
 430         unsigned long               s;
 431
 432         IA64_LOG_LOCK(sal_info_type);
 433
 434         /* Get the process state information */
 435         log_buffer = IA64_LOG_NEXT_BUFFER(sal_info_type);
 436
 437         total_len = ia64_sal_get_state_info(sal_info_type, (u64 *)log_buffer);
 438
 439         if (total_len) {
 440                 IA64_LOG_INDEX_INC(sal_info_type);
 441                 IA64_LOG_UNLOCK(sal_info_type);
 442                 if (irq_safe) {
 443                         IA64_MCA_DEBUG("%s: SAL error record type %d retrieved. Record length = %ld\n",
 444                                        __func__, sal_info_type, total_len);
 445                 }
 446                 *buffer = (u8 *) log_buffer;
 447                 return total_len;
 448         } else {
 449                 IA64_LOG_UNLOCK(sal_info_type);
 450                 return 0;
 451         }
 452 }
 453
 454 /*
 455  *  ia64_mca_log_sal_error_record
 456  *
 457  *  This function retrieves a specified error record type from SAL
 458  *  and wakes up any processes waiting for error records.
 459  *
 460  *  Inputs  :   sal_info_type   (Type of error record MCA/CMC/CPE)
 461  *              FIXME: remove MCA and irq_safe.
 462  */
 463 static void
 464 ia64_mca_log_sal_error_record(int sal_info_type)
 465 {
 466         u8 *buffer;
 467         sal_log_record_header_t *rh;
 468         u64 size;
 469         int irq_safe = sal_info_type != SAL_INFO_TYPE_MCA;
 470 #ifdef IA64_MCA_DEBUG_INFO
 471         static const char * const rec_name[] = { "MCA", "INIT", "CMC", "CPE" };
 472 #endif
 473
 474         size = ia64_log_get(sal_info_type, &buffer, irq_safe);
 475         if (!size)
 476                 return;
 477
 478         salinfo_log_wakeup(sal_info_type, buffer, size, irq_safe);
 479
 480         if (irq_safe)
 481                 IA64_MCA_DEBUG("CPU %d: SAL log contains %s error record\n",
 482                         smp_processor_id(),
 483                         sal_info_type < ARRAY_SIZE(rec_name) ? rec_name[sal_info_type] : "UNKNOWN");
 484
 485         /* Clear logs from corrected errors in case there's no user-level logger */
 486         rh = (sal_log_record_header_t *)buffer;
 487         if (rh->severity == sal_log_severity_corrected)
 488                 ia64_sal_clear_state_info(sal_info_type);
 489 }
 490
 491 /*
 492  * search_mca_table
 493  *  See if the MCA surfaced in an instruction range
 494  *  that has been tagged as recoverable.
 495  *
 496  *  Inputs
 497  *      first   First address range to check
 498  *      last    Last address range to check
 499  *      ip      Instruction pointer, address we are looking for
 500  *
 501  * Return value:
 502  *      1 on Success (in the table)/ 0 on Failure (not in the  table)
 503  */
 504 int
 505 search_mca_table (const struct mca_table_entry *first,
 506                 const struct mca_table_entry *last,
 507                 unsigned long ip)
 508 {
 509         const struct mca_table_entry *curr;
 510         u64 curr_start, curr_end;
 511
 512         curr = first;
 513         while (curr <= last) {
 514                 curr_start = (u64) &curr->start_addr + curr->start_addr;
 515                 curr_end = (u64) &curr->end_addr + curr->end_addr;
 516
 517                 if ((ip >= curr_start) && (ip <= curr_end)) {
 518                         return 1;
 519                 }
 520                 curr++;
 521         }
 522         return 0;
 523 }
 524
 525 /* Given an address, look for it in the mca tables. */
 526 int mca_recover_range(unsigned long addr)
 527 {
 528         extern struct mca_table_entry __start___mca_table[];
 529         extern struct mca_table_entry __stop___mca_table[];
 530
 531         return search_mca_table(__start___mca_table, __stop___mca_table-1, addr);
 532 }
 533 EXPORT_SYMBOL_GPL(mca_recover_range);
 534
 535 int cpe_vector = -1;
 536 int ia64_cpe_irq = -1;
 537
 538 static irqreturn_t
 539 ia64_mca_cpe_int_handler (int cpe_irq, void *arg)
 540 {
 541         static unsigned long    cpe_history[CPE_HISTORY_LENGTH];
 542         static int              index;
 543         static DEFINE_SPINLOCK(cpe_history_lock);
 544
 545         IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
 546                        __func__, cpe_irq, smp_processor_id());
 547
 548         /* SAL spec states this should run w/ interrupts enabled */
 549         local_irq_enable();
 550
 551         spin_lock(&cpe_history_lock);
 552         if (!cpe_poll_enabled && cpe_vector >= 0) {
 553
 554                 int i, count = 1; /* we know 1 happened now */
 555                 unsigned long now = jiffies;
 556
 557                 for (i = 0; i < CPE_HISTORY_LENGTH; i++) {
 558                         if (now - cpe_history[i] <= HZ)
 559                                 count++;
 560                 }
 561
 562                 IA64_MCA_DEBUG(KERN_INFO "CPE threshold %d/%d\n", count, CPE_HISTORY_LENGTH);
 563                 if (count >= CPE_HISTORY_LENGTH) {
 564
 565                         cpe_poll_enabled = 1;
 566                         spin_unlock(&cpe_history_lock);
 567                         disable_irq_nosync(local_vector_to_irq(IA64_CPE_VECTOR));
 568
 569                         /*
 570                          * Corrected errors will still be corrected, but
 571                          * make sure there's a log somewhere that indicates
 572                          * something is generating more than we can handle.
 573                          */
 574                         printk(KERN_WARNING "WARNING: Switching to polling CPE handler; error records may be lost\n");
 575
 576                         mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL);
 577
 578                         /* lock already released, get out now */
 579                         goto out;
 580                 } else {
 581                         cpe_history[index++] = now;
 582                         if (index == CPE_HISTORY_LENGTH)
 583                                 index = 0;
 584                 }
 585         }
 586         spin_unlock(&cpe_history_lock);
 587 out:
 588         /* Get the CPE error record and log it */
 589         ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE);
 590
 591         local_irq_disable();
 592
 593         return IRQ_HANDLED;
 594 }
 595
 596 /*
 597  * ia64_mca_register_cpev
 598  *
 599  *  Register the corrected platform error vector with SAL.
 600  *
 601  *  Inputs
 602  *      cpev        Corrected Platform Error Vector number
 603  *
 604  *  Outputs
 605  *      None
 606  */
 607 void
 608 ia64_mca_register_cpev (int cpev)
 609 {
 610         /* Register the CPE interrupt vector with SAL */
 611         struct ia64_sal_retval isrv;
 612
 613         isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_CPE_INT, SAL_MC_PARAM_MECHANISM_INT, cpev, 0, 0);
 614         if (isrv.status) {
 615                 printk(KERN_ERR "Failed to register Corrected Platform "
 616                        "Error interrupt vector with SAL (status %ld)\n", isrv.status);
 617                 return;
 618         }
 619
 620         IA64_MCA_DEBUG("%s: corrected platform error "
 621                        "vector %#x registered\n", __func__, cpev);
 622 }
 623
 624 /*
 625  * ia64_mca_cmc_vector_setup
 626  *
 627  *  Setup the corrected machine check vector register in the processor.
 628  *  (The interrupt is masked on boot. ia64_mca_late_init unmask this.)
 629  *  This function is invoked on a per-processor basis.
 630  *
 631  * Inputs
 632  *      None
 633  *
 634  * Outputs
 635  *      None
 636  */
 637 void
 638 ia64_mca_cmc_vector_setup (void)
 639 {
 640         cmcv_reg_t      cmcv;
 641
 642         cmcv.cmcv_regval        = 0;
 643         cmcv.cmcv_mask          = 1;        /* Mask/disable interrupt at first */
 644         cmcv.cmcv_vector        = IA64_CMC_VECTOR;
 645         ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
 646
 647         IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x registered.\n",
 648                        __func__, smp_processor_id(), IA64_CMC_VECTOR);
 649
 650         IA64_MCA_DEBUG("%s: CPU %d CMCV = %#016lx\n",
 651                        __func__, smp_processor_id(), ia64_getreg(_IA64_REG_CR_CMCV));
 652 }
 653
 654 /*
 655  * ia64_mca_cmc_vector_disable
 656  *
 657  *  Mask the corrected machine check vector register in the processor.
 658  *  This function is invoked on a per-processor basis.
 659  *
 660  * Inputs
 661  *      dummy(unused)
 662  *
 663  * Outputs
 664  *      None
 665  */
 666 static void
 667 ia64_mca_cmc_vector_disable (void *dummy)
 668 {
 669         cmcv_reg_t      cmcv;
 670
 671         cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
 672
 673         cmcv.cmcv_mask = 1; /* Mask/disable interrupt */
 674         ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
 675
 676         IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x disabled.\n",
 677                        __func__, smp_processor_id(), cmcv.cmcv_vector);
 678 }
 679
 680 /*
 681  * ia64_mca_cmc_vector_enable
 682  *
 683  *  Unmask the corrected machine check vector register in the processor.
 684  *  This function is invoked on a per-processor basis.
 685  *
 686  * Inputs
 687  *      dummy(unused)
 688  *
 689  * Outputs
 690  *      None
 691  */
 692 static void
 693 ia64_mca_cmc_vector_enable (void *dummy)
 694 {
 695         cmcv_reg_t      cmcv;
 696
 697         cmcv.cmcv_regval = ia64_getreg(_IA64_REG_CR_CMCV);
 698
 699         cmcv.cmcv_mask = 0; /* Unmask/enable interrupt */
 700         ia64_setreg(_IA64_REG_CR_CMCV, cmcv.cmcv_regval);
 701
 702         IA64_MCA_DEBUG("%s: CPU %d corrected machine check vector %#x enabled.\n",
 703                        __func__, smp_processor_id(), cmcv.cmcv_vector);
 704 }
 705
 706 /*
 707  * ia64_mca_cmc_vector_disable_keventd
 708  *
 709  * Called via keventd (smp_call_function() is not safe in interrupt context) to
 710  * disable the cmc interrupt vector.
 711  */
 712 static void
 713 ia64_mca_cmc_vector_disable_keventd(struct work_struct *unused)
 714 {
 715         on_each_cpu(ia64_mca_cmc_vector_disable, NULL, 0);
 716 }
 717
 718 /*
 719  * ia64_mca_cmc_vector_enable_keventd
 720  *
 721  * Called via keventd (smp_call_function() is not safe in interrupt context) to
 722  * enable the cmc interrupt vector.
 723  */
 724 static void
 725 ia64_mca_cmc_vector_enable_keventd(struct work_struct *unused)
 726 {
 727         on_each_cpu(ia64_mca_cmc_vector_enable, NULL, 0);
 728 }
 729
 730 /*
 731  * ia64_mca_wakeup
 732  *
 733  *      Send an inter-cpu interrupt to wake-up a particular cpu.
 734  *
 735  *  Inputs  :   cpuid
 736  *  Outputs :   None
 737  */
 738 static void
 739 ia64_mca_wakeup(int cpu)
 740 {
 741         ia64_send_ipi(cpu, IA64_MCA_WAKEUP_VECTOR, IA64_IPI_DM_INT, 0);
 742 }
 743
 744 /*
 745  * ia64_mca_wakeup_all
 746  *
 747  *      Wakeup all the slave cpus which have rendez'ed previously.
 748  *
 749  *  Inputs  :   None
 750  *  Outputs :   None
 751  */
 752 static void
 753 ia64_mca_wakeup_all(void)
 754 {
 755         int cpu;
 756
 757         /* Clear the Rendez checkin flag for all cpus */
 758         for_each_online_cpu(cpu) {
 759                 if (ia64_mc_info.imi_rendez_checkin[cpu] == IA64_MCA_RENDEZ_CHECKIN_DONE)
 760                         ia64_mca_wakeup(cpu);
 761         }
 762
 763 }
 764
 765 /*
 766  * ia64_mca_rendez_interrupt_handler
 767  *
 768  *      This is handler used to put slave processors into spinloop
 769  *      while the monarch processor does the mca handling and later
 770  *      wake each slave up once the monarch is done.  The state
 771  *      IA64_MCA_RENDEZ_CHECKIN_DONE indicates the cpu is rendez'ed
 772  *      in SAL.  The state IA64_MCA_RENDEZ_CHECKIN_NOTDONE indicates
 773  *      the cpu has come out of OS rendezvous.
 774  *
 775  *  Inputs  :   None
 776  *  Outputs :   None
 777  */
 778 static irqreturn_t
 779 ia64_mca_rendez_int_handler(int rendez_irq, void *arg)
 780 {
 781         unsigned long flags;
 782         int cpu = smp_processor_id();
 783         struct ia64_mca_notify_die nd =
 784                 { .sos = NULL, .monarch_cpu = &monarch_cpu };
 785
 786         /* Mask all interrupts */
 787         local_irq_save(flags);
 788
 789         NOTIFY_MCA(DIE_MCA_RENDZVOUS_ENTER, get_irq_regs(), (long)&nd, 1);
 790
 791         ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_DONE;
 792         /* Register with the SAL monarch that the slave has
 793          * reached SAL
 794          */
 795         ia64_sal_mc_rendez();
 796
 797         NOTIFY_MCA(DIE_MCA_RENDZVOUS_PROCESS, get_irq_regs(), (long)&nd, 1);
 798
 799         /* Wait for the monarch cpu to exit. */
 800         while (monarch_cpu != -1)
 801                cpu_relax();     /* spin until monarch leaves */
 802
 803         NOTIFY_MCA(DIE_MCA_RENDZVOUS_LEAVE, get_irq_regs(), (long)&nd, 1);
 804
 805         ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
 806         /* Enable all interrupts */
 807         local_irq_restore(flags);
 808         return IRQ_HANDLED;
 809 }
 810
 811 /*
 812  * ia64_mca_wakeup_int_handler
 813  *
 814  *      The interrupt handler for processing the inter-cpu interrupt to the
 815  *      slave cpu which was spinning in the rendez loop.
 816  *      Since this spinning is done by turning off the interrupts and
 817  *      polling on the wakeup-interrupt bit in the IRR, there is
 818  *      nothing useful to be done in the handler.
 819  *
 820  *  Inputs  :   wakeup_irq  (Wakeup-interrupt bit)
 821  *      arg             (Interrupt handler specific argument)
 822  *  Outputs :   None
 823  *
 824  */
 825 static irqreturn_t
 826 ia64_mca_wakeup_int_handler(int wakeup_irq, void *arg)
 827 {
 828         return IRQ_HANDLED;
 829 }
 830
 831 /* Function pointer for extra MCA recovery */
 832 int (*ia64_mca_ucmc_extension)
 833         (void*,struct ia64_sal_os_state*)
 834         = NULL;
 835
 836 int
 837 ia64_reg_MCA_extension(int (*fn)(void *, struct ia64_sal_os_state *))
 838 {
 839         if (ia64_mca_ucmc_extension)
 840                 return 1;
 841
 842         ia64_mca_ucmc_extension = fn;
 843         return 0;
 844 }
 845
 846 void
 847 ia64_unreg_MCA_extension(void)
 848 {
 849         if (ia64_mca_ucmc_extension)
 850                 ia64_mca_ucmc_extension = NULL;
 851 }
 852
 853 EXPORT_SYMBOL(ia64_reg_MCA_extension);
 854 EXPORT_SYMBOL(ia64_unreg_MCA_extension);
 855
 856
 857 static inline void
 858 copy_reg(const u64 *fr, u64 fnat, unsigned long *tr, unsigned long *tnat)
 859 {
 860         u64 fslot, tslot, nat;
 861         *tr = *fr;
 862         fslot = ((unsigned long)fr >> 3) & 63;
 863         tslot = ((unsigned long)tr >> 3) & 63;
 864         *tnat &= ~(1UL << tslot);
 865         nat = (fnat >> fslot) & 1;
 866         *tnat |= (nat << tslot);
 867 }
 868
 869 /* Change the comm field on the MCA/INT task to include the pid that
 870  * was interrupted, it makes for easier debugging.  If that pid was 0
 871  * (swapper or nested MCA/INIT) then use the start of the previous comm
 872  * field suffixed with its cpu.
 873  */
 874
 875 static void
 876 ia64_mca_modify_comm(const struct task_struct *previous_current)
 877 {
 878         char *p, comm[sizeof(current->comm)];
 879         if (previous_current->pid)
 880                 snprintf(comm, sizeof(comm), "%s %d",
 881                         current->comm, previous_current->pid);
 882         else {
 883                 int l;
 884                 if ((p = strchr(previous_current->comm, ' ')))
 885                         l = p - previous_current->comm;
 886                 else
 887                         l = strlen(previous_current->comm);
 888                 snprintf(comm, sizeof(comm), "%s %*s %d",
 889                         current->comm, l, previous_current->comm,
 890                         task_thread_info(previous_current)->cpu);
 891         }
 892         memcpy(current->comm, comm, sizeof(current->comm));
 893 }
 894
 895 static void
 896 finish_pt_regs(struct pt_regs *regs, struct ia64_sal_os_state *sos,
 897                 unsigned long *nat)
 898 {
 899         const struct pal_min_state_area *ms = sos->pal_min_state;
 900         const u64 *bank;
 901
 902         /* If ipsr.ic then use pmsa_{iip,ipsr,ifs}, else use
 903          * pmsa_{xip,xpsr,xfs}
 904          */
 905         if (ia64_psr(regs)->ic) {
 906                 regs->cr_iip = ms->pmsa_iip;
 907                 regs->cr_ipsr = ms->pmsa_ipsr;
 908                 regs->cr_ifs = ms->pmsa_ifs;
 909         } else {
 910                 regs->cr_iip = ms->pmsa_xip;
 911                 regs->cr_ipsr = ms->pmsa_xpsr;
 912                 regs->cr_ifs = ms->pmsa_xfs;
 913
 914                 sos->iip = ms->pmsa_iip;
 915                 sos->ipsr = ms->pmsa_ipsr;
 916                 sos->ifs = ms->pmsa_ifs;
 917         }
 918         regs->pr = ms->pmsa_pr;
 919         regs->b0 = ms->pmsa_br0;
 920         regs->ar_rsc = ms->pmsa_rsc;
 921         copy_reg(&ms->pmsa_gr[1-1], ms->pmsa_nat_bits, &regs->r1, nat);
 922         copy_reg(&ms->pmsa_gr[2-1], ms->pmsa_nat_bits, &regs->r2, nat);
 923         copy_reg(&ms->pmsa_gr[3-1], ms->pmsa_nat_bits, &regs->r3, nat);
 924         copy_reg(&ms->pmsa_gr[8-1], ms->pmsa_nat_bits, &regs->r8, nat);
 925         copy_reg(&ms->pmsa_gr[9-1], ms->pmsa_nat_bits, &regs->r9, nat);
 926         copy_reg(&ms->pmsa_gr[10-1], ms->pmsa_nat_bits, &regs->r10, nat);
 927         copy_reg(&ms->pmsa_gr[11-1], ms->pmsa_nat_bits, &regs->r11, nat);
 928         copy_reg(&ms->pmsa_gr[12-1], ms->pmsa_nat_bits, &regs->r12, nat);
 929         copy_reg(&ms->pmsa_gr[13-1], ms->pmsa_nat_bits, &regs->r13, nat);
 930         copy_reg(&ms->pmsa_gr[14-1], ms->pmsa_nat_bits, &regs->r14, nat);
 931         copy_reg(&ms->pmsa_gr[15-1], ms->pmsa_nat_bits, &regs->r15, nat);
 932         if (ia64_psr(regs)->bn)
 933                 bank = ms->pmsa_bank1_gr;
 934         else
 935                 bank = ms->pmsa_bank0_gr;
 936         copy_reg(&bank[16-16], ms->pmsa_nat_bits, &regs->r16, nat);
 937         copy_reg(&bank[17-16], ms->pmsa_nat_bits, &regs->r17, nat);
 938         copy_reg(&bank[18-16], ms->pmsa_nat_bits, &regs->r18, nat);
 939         copy_reg(&bank[19-16], ms->pmsa_nat_bits, &regs->r19, nat);
 940         copy_reg(&bank[20-16], ms->pmsa_nat_bits, &regs->r20, nat);
 941         copy_reg(&bank[21-16], ms->pmsa_nat_bits, &regs->r21, nat);
 942         copy_reg(&bank[22-16], ms->pmsa_nat_bits, &regs->r22, nat);
 943         copy_reg(&bank[23-16], ms->pmsa_nat_bits, &regs->r23, nat);
 944         copy_reg(&bank[24-16], ms->pmsa_nat_bits, &regs->r24, nat);
 945         copy_reg(&bank[25-16], ms->pmsa_nat_bits, &regs->r25, nat);
 946         copy_reg(&bank[26-16], ms->pmsa_nat_bits, &regs->r26, nat);
 947         copy_reg(&bank[27-16], ms->pmsa_nat_bits, &regs->r27, nat);
 948         copy_reg(&bank[28-16], ms->pmsa_nat_bits, &regs->r28, nat);
 949         copy_reg(&bank[29-16], ms->pmsa_nat_bits, &regs->r29, nat);
 950         copy_reg(&bank[30-16], ms->pmsa_nat_bits, &regs->r30, nat);
 951         copy_reg(&bank[31-16], ms->pmsa_nat_bits, &regs->r31, nat);
 952 }
 953
 954 /* On entry to this routine, we are running on the per cpu stack, see
 955  * mca_asm.h.  The original stack has not been touched by this event.  Some of
 956  * the original stack's registers will be in the RBS on this stack.  This stack
 957  * also contains a partial pt_regs and switch_stack, the rest of the data is in
 958  * PAL minstate.
 959  *
 960  * The first thing to do is modify the original stack to look like a blocked
 961  * task so we can run backtrace on the original task.  Also mark the per cpu
 962  * stack as current to ensure that we use the correct task state, it also means
 963  * that we can do backtrace on the MCA/INIT handler code itself.
 964  */
 965
 966 static struct task_struct *
 967 ia64_mca_modify_original_stack(struct pt_regs *regs,
 968                 const struct switch_stack *sw,
 969                 struct ia64_sal_os_state *sos,
 970                 const char *type)
 971 {
 972         char *p;
 973         ia64_va va;
 974         extern char ia64_leave_kernel[];        /* Need asm address, not function descriptor */
 975         const struct pal_min_state_area *ms = sos->pal_min_state;
 976         struct task_struct *previous_current;
 977         struct pt_regs *old_regs;
 978         struct switch_stack *old_sw;
 979         unsigned size = sizeof(struct pt_regs) +
 980                         sizeof(struct switch_stack) + 16;
 981         unsigned long *old_bspstore, *old_bsp;
 982         unsigned long *new_bspstore, *new_bsp;
 983         unsigned long old_unat, old_rnat, new_rnat, nat;
 984         u64 slots, loadrs = regs->loadrs;
 985         u64 r12 = ms->pmsa_gr[12-1], r13 = ms->pmsa_gr[13-1];
 986         u64 ar_bspstore = regs->ar_bspstore;
 987         u64 ar_bsp = regs->ar_bspstore + (loadrs >> 16);
 988         const char *msg;
 989         int cpu = smp_processor_id();
 990
 991         previous_current = curr_task(cpu);
 992         ia64_set_curr_task(cpu, current);
 993         if ((p = strchr(current->comm, ' ')))
 994                 *p = '\0';
 995
 996         /* Best effort attempt to cope with MCA/INIT delivered while in
 997          * physical mode.
 998          */
 999         regs->cr_ipsr = ms->pmsa_ipsr;
1000         if (ia64_psr(regs)->dt == 0) {
1001                 va.l = r12;
1002                 if (va.f.reg == 0) {
1003                         va.f.reg = 7;
1004                         r12 = va.l;
1005                 }
1006                 va.l = r13;
1007                 if (va.f.reg == 0) {
1008                         va.f.reg = 7;
1009                         r13 = va.l;
1010                 }
1011         }
1012         if (ia64_psr(regs)->rt == 0) {
1013                 va.l = ar_bspstore;
1014                 if (va.f.reg == 0) {
1015                         va.f.reg = 7;
1016                         ar_bspstore = va.l;
1017                 }
1018                 va.l = ar_bsp;
1019                 if (va.f.reg == 0) {
1020                         va.f.reg = 7;
1021                         ar_bsp = va.l;
1022                 }
1023         }
1024
1025         /* mca_asm.S ia64_old_stack() cannot assume that the dirty registers
1026          * have been copied to the old stack, the old stack may fail the
1027          * validation tests below.  So ia64_old_stack() must restore the dirty
1028          * registers from the new stack.  The old and new bspstore probably
1029          * have different alignments, so loadrs calculated on the old bsp
1030          * cannot be used to restore from the new bsp.  Calculate a suitable
1031          * loadrs for the new stack and save it in the new pt_regs, where
1032          * ia64_old_stack() can get it.
1033          */
1034         old_bspstore = (unsigned long *)ar_bspstore;
1035         old_bsp = (unsigned long *)ar_bsp;
1036         slots = ia64_rse_num_regs(old_bspstore, old_bsp);
1037         new_bspstore = (unsigned long *)((u64)current + IA64_RBS_OFFSET);
1038         new_bsp = ia64_rse_skip_regs(new_bspstore, slots);
1039         regs->loadrs = (new_bsp - new_bspstore) * 8 << 16;
1040
1041         /* Verify the previous stack state before we change it */
1042         if (user_mode(regs)) {
1043                 msg = "occurred in user space";
1044                 /* previous_current is guaranteed to be valid when the task was
1045                  * in user space, so ...
1046                  */
1047                 ia64_mca_modify_comm(previous_current);
1048                 goto no_mod;
1049         }
1050
1051         if (r13 != sos->prev_IA64_KR_CURRENT) {
1052                 msg = "inconsistent previous current and r13";
1053                 goto no_mod;
1054         }
1055
1056         if (!mca_recover_range(ms->pmsa_iip)) {
1057                 if ((r12 - r13) >= KERNEL_STACK_SIZE) {
1058                         msg = "inconsistent r12 and r13";
1059                         goto no_mod;
1060                 }
1061                 if ((ar_bspstore - r13) >= KERNEL_STACK_SIZE) {
1062                         msg = "inconsistent ar.bspstore and r13";
1063                         goto no_mod;
1064                 }
1065                 va.p = old_bspstore;
1066                 if (va.f.reg < 5) {
1067                         msg = "old_bspstore is in the wrong region";
1068                         goto no_mod;
1069                 }
1070                 if ((ar_bsp - r13) >= KERNEL_STACK_SIZE) {
1071                         msg = "inconsistent ar.bsp and r13";
1072                         goto no_mod;
1073                 }
1074                 size += (ia64_rse_skip_regs(old_bspstore, slots) - old_bspstore) * 8;
1075                 if (ar_bspstore + size > r12) {
1076                         msg = "no room for blocked state";
1077                         goto no_mod;
1078                 }
1079         }
1080
1081         ia64_mca_modify_comm(previous_current);
1082
1083         /* Make the original task look blocked.  First stack a struct pt_regs,
1084          * describing the state at the time of interrupt.  mca_asm.S built a
1085          * partial pt_regs, copy it and fill in the blanks using minstate.
1086          */
1087         p = (char *)r12 - sizeof(*regs);
1088         old_regs = (struct pt_regs *)p;
1089         memcpy(old_regs, regs, sizeof(*regs));
1090         old_regs->loadrs = loadrs;
1091         old_unat = old_regs->ar_unat;
1092         finish_pt_regs(old_regs, sos, &old_unat);
1093
1094         /* Next stack a struct switch_stack.  mca_asm.S built a partial
1095          * switch_stack, copy it and fill in the blanks using pt_regs and
1096          * minstate.
1097          *
1098          * In the synthesized switch_stack, b0 points to ia64_leave_kernel,
1099          * ar.pfs is set to 0.
1100          *
1101          * unwind.c::unw_unwind() does special processing for interrupt frames.
1102          * It checks if the PRED_NON_SYSCALL predicate is set, if the predicate
1103          * is clear then unw_unwind() does _not_ adjust bsp over pt_regs.  Not
1104          * that this is documented, of course.  Set PRED_NON_SYSCALL in the
1105          * switch_stack on the original stack so it will unwind correctly when
1106          * unwind.c reads pt_regs.
1107          *
1108          * thread.ksp is updated to point to the synthesized switch_stack.
1109          */
1110         p -= sizeof(struct switch_stack);
1111         old_sw = (struct switch_stack *)p;
1112         memcpy(old_sw, sw, sizeof(*sw));
1113         old_sw->caller_unat = old_unat;
1114         old_sw->ar_fpsr = old_regs->ar_fpsr;
1115         copy_reg(&ms->pmsa_gr[4-1], ms->pmsa_nat_bits, &old_sw->r4, &old_unat);
1116         copy_reg(&ms->pmsa_gr[5-1], ms->pmsa_nat_bits, &old_sw->r5, &old_unat);
1117         copy_reg(&ms->pmsa_gr[6-1], ms->pmsa_nat_bits, &old_sw->r6, &old_unat);
1118         copy_reg(&ms->pmsa_gr[7-1], ms->pmsa_nat_bits, &old_sw->r7, &old_unat);
1119         old_sw->b0 = (u64)ia64_leave_kernel;
1120         old_sw->b1 = ms->pmsa_br1;
1121         old_sw->ar_pfs = 0;
1122         old_sw->ar_unat = old_unat;
1123         old_sw->pr = old_regs->pr | (1UL << PRED_NON_SYSCALL);
1124         previous_current->thread.ksp = (u64)p - 16;
1125
1126         /* Finally copy the original stack's registers back to its RBS.
1127          * Registers from ar.bspstore through ar.bsp at the time of the event
1128          * are in the current RBS, copy them back to the original stack.  The
1129          * copy must be done register by register because the original bspstore
1130          * and the current one have different alignments, so the saved RNAT
1131          * data occurs at different places.
1132          *
1133          * mca_asm does cover, so the old_bsp already includes all registers at
1134          * the time of MCA/INIT.  It also does flushrs, so all registers before
1135          * this function have been written to backing store on the MCA/INIT
1136          * stack.
1137          */
1138         new_rnat = ia64_get_rnat(ia64_rse_rnat_addr(new_bspstore));
1139         old_rnat = regs->ar_rnat;
1140         while (slots--) {
1141                 if (ia64_rse_is_rnat_slot(new_bspstore)) {
1142                         new_rnat = ia64_get_rnat(new_bspstore++);
1143                 }
1144                 if (ia64_rse_is_rnat_slot(old_bspstore)) {
1145                         *old_bspstore++ = old_rnat;
1146                         old_rnat = 0;
1147                 }
1148                 nat = (new_rnat >> ia64_rse_slot_num(new_bspstore)) & 1UL;
1149                 old_rnat &= ~(1UL << ia64_rse_slot_num(old_bspstore));
1150                 old_rnat |= (nat << ia64_rse_slot_num(old_bspstore));
1151                 *old_bspstore++ = *new_bspstore++;
1152         }
1153         old_sw->ar_bspstore = (unsigned long)old_bspstore;
1154         old_sw->ar_rnat = old_rnat;
1155
1156         sos->prev_task = previous_current;
1157         return previous_current;
1158
1159 no_mod:
1160         mprintk(KERN_INFO "cpu %d, %s %s, original stack not modified\n",
1161                         smp_processor_id(), type, msg);
1162         old_unat = regs->ar_unat;
1163         finish_pt_regs(regs, sos, &old_unat);
1164         return previous_current;
1165 }
1166
1167 /* The monarch/slave interaction is based on monarch_cpu and requires that all
1168  * slaves have entered rendezvous before the monarch leaves.  If any cpu has
1169  * not entered rendezvous yet then wait a bit.  The assumption is that any
1170  * slave that has not rendezvoused after a reasonable time is never going to do
1171  * so.  In this context, slave includes cpus that respond to the MCA rendezvous
1172  * interrupt, as well as cpus that receive the INIT slave event.
1173  */
1174
1175 static void
1176 ia64_wait_for_slaves(int monarch, const char *type)
1177 {
1178         int c, i , wait;
1179
1180         /*
1181          * wait 5 seconds total for slaves (arbitrary)
1182          */
1183         for (i = 0; i < 5000; i++) {
1184                 wait = 0;
1185                 for_each_online_cpu(c) {
1186                         if (c == monarch)
1187                                 continue;
1188                         if (ia64_mc_info.imi_rendez_checkin[c]
1189                                         == IA64_MCA_RENDEZ_CHECKIN_NOTDONE) {
1190                                 udelay(1000);           /* short wait */
1191                                 wait = 1;
1192                                 break;
1193                         }
1194                 }
1195                 if (!wait)
1196                         goto all_in;
1197         }
1198
1199         /*
1200          * Maybe slave(s) dead. Print buffered messages immediately.
1201          */
1202         ia64_mlogbuf_finish(0);
1203         mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
1204         for_each_online_cpu(c) {
1205                 if (c == monarch)
1206                         continue;
1207                 if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
1208                         mprintk(" %d", c);
1209         }
1210         mprintk("\n");
1211         return;
1212
1213 all_in:
1214         mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
1215         return;
1216 }
1217
1218 /*  mca_insert_tr
1219  *
1220  *  Switch rid when TR reload and needed!
1221  *  iord: 1: itr, 2: itr;
1222  *
1223 */
1224 static void mca_insert_tr(u64 iord)
1225 {
1226
1227         int i;
1228         u64 old_rr;
1229         struct ia64_tr_entry *p;
1230         unsigned long psr;
1231         int cpu = smp_processor_id();
1232
1233         if (!ia64_idtrs[cpu])
1234                 return;
1235
1236         psr = ia64_clear_ic();
1237         for (i = IA64_TR_ALLOC_BASE; i < IA64_TR_ALLOC_MAX; i++) {
1238                 p = ia64_idtrs[cpu] + (iord - 1) * IA64_TR_ALLOC_MAX;
1239                 if (p->pte & 0x1) {
1240                         old_rr = ia64_get_rr(p->ifa);
1241                         if (old_rr != p->rr) {
1242                                 ia64_set_rr(p->ifa, p->rr);
1243                                 ia64_srlz_d();
1244                         }
1245                         ia64_ptr(iord, p->ifa, p->itir >> 2);
1246                         ia64_srlz_i();
1247                         if (iord & 0x1) {
1248                                 ia64_itr(0x1, i, p->ifa, p->pte, p->itir >> 2);
1249                                 ia64_srlz_i();
1250                         }
1251                         if (iord & 0x2) {
1252                                 ia64_itr(0x2, i, p->ifa, p->pte, p->itir >> 2);
1253                                 ia64_srlz_i();
1254                         }
1255                         if (old_rr != p->rr) {
1256                                 ia64_set_rr(p->ifa, old_rr);
1257                                 ia64_srlz_d();
1258                         }
1259                 }
1260         }
1261         ia64_set_psr(psr);
1262 }
1263
1264 /*
1265  * ia64_mca_handler
1266  *
1267  *      This is uncorrectable machine check handler called from OS_MCA
1268  *      dispatch code which is in turn called from SAL_CHECK().
1269  *      This is the place where the core of OS MCA handling is done.
1270  *      Right now the logs are extracted and displayed in a well-defined
1271  *      format. This handler code is supposed to be run only on the
1272  *      monarch processor. Once the monarch is done with MCA handling
1273  *      further MCA logging is enabled by clearing logs.
1274  *      Monarch also has the duty of sending wakeup-IPIs to pull the
1275  *      slave processors out of rendezvous spinloop.
1276  *
1277  *      If multiple processors call into OS_MCA, the first will become
1278  *      the monarch.  Subsequent cpus will be recorded in the mca_cpu
1279  *      bitmask.  After the first monarch has processed its MCA, it
1280  *      will wake up the next cpu in the mca_cpu bitmask and then go
1281  *      into the rendezvous loop.  When all processors have serviced
1282  *      their MCA, the last monarch frees up the rest of the processors.
1283  */
1284 void
1285 ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
1286                  struct ia64_sal_os_state *sos)
1287 {
1288         int recover, cpu = smp_processor_id();
1289         struct task_struct *previous_current;
1290         struct ia64_mca_notify_die nd =
1291                 { .sos = sos, .monarch_cpu = &monarch_cpu, .data = &recover };
1292         static atomic_t mca_count;
1293         static cpumask_t mca_cpu;
1294
1295         if (atomic_add_return(1, &mca_count) == 1) {
1296                 monarch_cpu = cpu;
1297                 sos->monarch = 1;
1298         } else {
1299                 cpumask_set_cpu(cpu, &mca_cpu);
1300                 sos->monarch = 0;
1301         }
1302         mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
1303                 "monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
1304
1305         previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
1306
1307         NOTIFY_MCA(DIE_MCA_MONARCH_ENTER, regs, (long)&nd, 1);
1308
1309         ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_CONCURRENT_MCA;
1310         if (sos->monarch) {
1311                 ia64_wait_for_slaves(cpu, "MCA");
1312
1313                 /* Wakeup all the processors which are spinning in the
1314                  * rendezvous loop.  They will leave SAL, then spin in the OS
1315                  * with interrupts disabled until this monarch cpu leaves the
1316                  * MCA handler.  That gets control back to the OS so we can
1317                  * backtrace the other cpus, backtrace when spinning in SAL
1318                  * does not work.
1319                  */
1320                 ia64_mca_wakeup_all();
1321         } else {
1322                 while (cpumask_test_cpu(cpu, &mca_cpu))
1323                         cpu_relax();    /* spin until monarch wakes us */
1324         }
1325
1326         NOTIFY_MCA(DIE_MCA_MONARCH_PROCESS, regs, (long)&nd, 1);
1327
1328         /* Get the MCA error record and log it */
1329         ia64_mca_log_sal_error_record(SAL_INFO_TYPE_MCA);
1330
1331         /* MCA error recovery */
1332         recover = (ia64_mca_ucmc_extension
1333                 && ia64_mca_ucmc_extension(
1334                         IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA),
1335                         sos));
1336
1337         if (recover) {
1338                 sal_log_record_header_t *rh = IA64_LOG_CURR_BUFFER(SAL_INFO_TYPE_MCA);
1339                 rh->severity = sal_log_severity_corrected;
1340                 ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
1341                 sos->os_status = IA64_MCA_CORRECTED;
1342         } else {
1343                 /* Dump buffered message to console */
1344                 ia64_mlogbuf_finish(1);
1345         }
1346
1347         if (__this_cpu_read(ia64_mca_tr_reload)) {
1348                 mca_insert_tr(0x1); /*Reload dynamic itrs*/
1349                 mca_insert_tr(0x2); /*Reload dynamic itrs*/
1350         }
1351
1352         NOTIFY_MCA(DIE_MCA_MONARCH_LEAVE, regs, (long)&nd, 1);
1353
1354         if (atomic_dec_return(&mca_count) > 0) {
1355                 int i;
1356
1357                 /* wake up the next monarch cpu,
1358                  * and put this cpu in the rendez loop.
1359                  */
1360                 for_each_online_cpu(i) {
1361                         if (cpumask_test_cpu(i, &mca_cpu)) {
1362                                 monarch_cpu = i;
1363                                 cpumask_clear_cpu(i, &mca_cpu); /* wake next cpu */
1364                                 while (monarch_cpu != -1)
1365                                         cpu_relax();    /* spin until last cpu leaves */
1366                                 ia64_set_curr_task(cpu, previous_current);
1367                                 ia64_mc_info.imi_rendez_checkin[cpu]
1368                                                 = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1369                                 return;
1370                         }
1371                 }
1372         }
1373         ia64_set_curr_task(cpu, previous_current);
1374         ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1375         monarch_cpu = -1;       /* This frees the slaves and previous monarchs */
1376 }
1377
1378 static DECLARE_WORK(cmc_disable_work, ia64_mca_cmc_vector_disable_keventd);
1379 static DECLARE_WORK(cmc_enable_work, ia64_mca_cmc_vector_enable_keventd);
1380
1381 /*
1382  * ia64_mca_cmc_int_handler
1383  *
1384  *  This is corrected machine check interrupt handler.
1385  *      Right now the logs are extracted and displayed in a well-defined
1386  *      format.
1387  *
1388  * Inputs
1389  *      interrupt number
1390  *      client data arg ptr
1391  *
1392  * Outputs
1393  *      None
1394  */
1395 static irqreturn_t
1396 ia64_mca_cmc_int_handler(int cmc_irq, void *arg)
1397 {
1398         static unsigned long    cmc_history[CMC_HISTORY_LENGTH];
1399         static int              index;
1400         static DEFINE_SPINLOCK(cmc_history_lock);
1401
1402         IA64_MCA_DEBUG("%s: received interrupt vector = %#x on CPU %d\n",
1403                        __func__, cmc_irq, smp_processor_id());
1404
1405         /* SAL spec states this should run w/ interrupts enabled */
1406         local_irq_enable();
1407
1408         spin_lock(&cmc_history_lock);
1409         if (!cmc_polling_enabled) {
1410                 int i, count = 1; /* we know 1 happened now */
1411                 unsigned long now = jiffies;
1412
1413                 for (i = 0; i < CMC_HISTORY_LENGTH; i++) {
1414                         if (now - cmc_history[i] <= HZ)
1415                                 count++;
1416                 }
1417
1418                 IA64_MCA_DEBUG(KERN_INFO "CMC threshold %d/%d\n", count, CMC_HISTORY_LENGTH);
1419                 if (count >= CMC_HISTORY_LENGTH) {
1420
1421                         cmc_polling_enabled = 1;
1422                         spin_unlock(&cmc_history_lock);
1423                         /* If we're being hit with CMC interrupts, we won't
1424                          * ever execute the schedule_work() below.  Need to
1425                          * disable CMC interrupts on this processor now.
1426                          */
1427                         ia64_mca_cmc_vector_disable(NULL);
1428                         schedule_work(&cmc_disable_work);
1429
1430                         /*
1431                          * Corrected errors will still be corrected, but
1432                          * make sure there's a log somewhere that indicates
1433                          * something is generating more than we can handle.
1434                          */
1435                         printk(KERN_WARNING "WARNING: Switching to polling CMC handler; error records may be lost\n");
1436
1437                         mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1438
1439                         /* lock already released, get out now */
1440                         goto out;
1441                 } else {
1442                         cmc_history[index++] = now;
1443                         if (index == CMC_HISTORY_LENGTH)
1444                                 index = 0;
1445                 }
1446         }
1447         spin_unlock(&cmc_history_lock);
1448 out:
1449         /* Get the CMC error record and log it */
1450         ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC);
1451
1452         local_irq_disable();
1453
1454         return IRQ_HANDLED;
1455 }
1456
1457 /*
1458  *  ia64_mca_cmc_int_caller
1459  *
1460  *      Triggered by sw interrupt from CMC polling routine.  Calls
1461  *      real interrupt handler and either triggers a sw interrupt
1462  *      on the next cpu or does cleanup at the end.
1463  *
1464  * Inputs
1465  *      interrupt number
1466  *      client data arg ptr
1467  * Outputs
1468  *      handled
1469  */
1470 static irqreturn_t
1471 ia64_mca_cmc_int_caller(int cmc_irq, void *arg)
1472 {
1473         static int start_count = -1;
1474         unsigned int cpuid;
1475
1476         cpuid = smp_processor_id();
1477
1478         /* If first cpu, update count */
1479         if (start_count == -1)
1480                 start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CMC);
1481
1482         ia64_mca_cmc_int_handler(cmc_irq, arg);
1483
1484         cpuid = cpumask_next(cpuid+1, cpu_online_mask);
1485
1486         if (cpuid < nr_cpu_ids) {
1487                 ia64_send_ipi(cpuid, IA64_CMCP_VECTOR, IA64_IPI_DM_INT, 0);
1488         } else {
1489                 /* If no log record, switch out of polling mode */
1490                 if (start_count == IA64_LOG_COUNT(SAL_INFO_TYPE_CMC)) {
1491
1492                         printk(KERN_WARNING "Returning to interrupt driven CMC handler\n");
1493                         schedule_work(&cmc_enable_work);
1494                         cmc_polling_enabled = 0;
1495
1496                 } else {
1497
1498                         mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL);
1499                 }
1500
1501                 start_count = -1;
1502         }
1503
1504         return IRQ_HANDLED;
1505 }
1506
1507 /*
1508  *  ia64_mca_cmc_poll
1509  *
1510  *      Poll for Corrected Machine Checks (CMCs)
1511  *
1512  * Inputs   :   dummy(unused)
1513  * Outputs  :   None
1514  *
1515  */
1516 static void
1517 ia64_mca_cmc_poll (struct timer_list *unused)
1518 {
1519         /* Trigger a CMC interrupt cascade  */
1520         ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CMCP_VECTOR,
1521                                                         IA64_IPI_DM_INT, 0);
1522 }
1523
1524 /*
1525  *  ia64_mca_cpe_int_caller
1526  *
1527  *      Triggered by sw interrupt from CPE polling routine.  Calls
1528  *      real interrupt handler and either triggers a sw interrupt
1529  *      on the next cpu or does cleanup at the end.
1530  *
1531  * Inputs
1532  *      interrupt number
1533  *      client data arg ptr
1534  * Outputs
1535  *      handled
1536  */
1537 static irqreturn_t
1538 ia64_mca_cpe_int_caller(int cpe_irq, void *arg)
1539 {
1540         static int start_count = -1;
1541         static int poll_time = MIN_CPE_POLL_INTERVAL;
1542         unsigned int cpuid;
1543
1544         cpuid = smp_processor_id();
1545
1546         /* If first cpu, update count */
1547         if (start_count == -1)
1548                 start_count = IA64_LOG_COUNT(SAL_INFO_TYPE_CPE);
1549
1550         ia64_mca_cpe_int_handler(cpe_irq, arg);
1551
1552         cpuid = cpumask_next(cpuid+1, cpu_online_mask);
1553
1554         if (cpuid < NR_CPUS) {
1555                 ia64_send_ipi(cpuid, IA64_CPEP_VECTOR, IA64_IPI_DM_INT, 0);
1556         } else {
1557                 /*
1558                  * If a log was recorded, increase our polling frequency,
1559                  * otherwise, backoff or return to interrupt mode.
1560                  */
1561                 if (start_count != IA64_LOG_COUNT(SAL_INFO_TYPE_CPE)) {
1562                         poll_time = max(MIN_CPE_POLL_INTERVAL, poll_time / 2);
1563                 } else if (cpe_vector < 0) {
1564                         poll_time = min(MAX_CPE_POLL_INTERVAL, poll_time * 2);
1565                 } else {
1566                         poll_time = MIN_CPE_POLL_INTERVAL;
1567
1568                         printk(KERN_WARNING "Returning to interrupt driven CPE handler\n");
1569                         enable_irq(local_vector_to_irq(IA64_CPE_VECTOR));
1570                         cpe_poll_enabled = 0;
1571                 }
1572
1573                 if (cpe_poll_enabled)
1574                         mod_timer(&cpe_poll_timer, jiffies + poll_time);
1575                 start_count = -1;
1576         }
1577
1578         return IRQ_HANDLED;
1579 }
1580
1581 /*
1582  *  ia64_mca_cpe_poll
1583  *
1584  *      Poll for Corrected Platform Errors (CPEs), trigger interrupt
1585  *      on first cpu, from there it will trickle through all the cpus.
1586  *
1587  * Inputs   :   dummy(unused)
1588  * Outputs  :   None
1589  *
1590  */
1591 static void
1592 ia64_mca_cpe_poll (struct timer_list *unused)
1593 {
1594         /* Trigger a CPE interrupt cascade  */
1595         ia64_send_ipi(cpumask_first(cpu_online_mask), IA64_CPEP_VECTOR,
1596                                                         IA64_IPI_DM_INT, 0);
1597 }
1598
1599 static int
1600 default_monarch_init_process(struct notifier_block *self, unsigned long val, void *data)
1601 {
1602         int c;
1603         struct task_struct *g, *t;
1604         if (val != DIE_INIT_MONARCH_PROCESS)
1605                 return NOTIFY_DONE;
1606 #ifdef CONFIG_KEXEC
1607         if (atomic_read(&kdump_in_progress))
1608                 return NOTIFY_DONE;
1609 #endif
1610
1611         /*
1612          * FIXME: mlogbuf will brim over with INIT stack dumps.
1613          * To enable show_stack from INIT, we use oops_in_progress which should
1614          * be used in real oops. This would cause something wrong after INIT.
1615          */
1616         BREAK_LOGLEVEL(console_loglevel);
1617         ia64_mlogbuf_dump_from_init();
1618
1619         printk(KERN_ERR "Processes interrupted by INIT -");
1620         for_each_online_cpu(c) {
1621                 struct ia64_sal_os_state *s;
1622                 t = __va(__per_cpu_mca[c] + IA64_MCA_CPU_INIT_STACK_OFFSET);
1623                 s = (struct ia64_sal_os_state *)((char *)t + MCA_SOS_OFFSET);
1624                 g = s->prev_task;
1625                 if (g) {
1626                         if (g->pid)
1627                                 printk(" %d", g->pid);
1628                         else
1629                                 printk(" %d (cpu %d task 0x%p)", g->pid, task_cpu(g), g);
1630                 }
1631         }
1632         printk("\n\n");
1633         if (read_trylock(&tasklist_lock)) {
1634                 do_each_thread (g, t) {
1635                         printk("\nBacktrace of pid %d (%s)\n", t->pid, t->comm);
1636                         show_stack(t, NULL, KERN_DEFAULT);
1637                 } while_each_thread (g, t);
1638                 read_unlock(&tasklist_lock);
1639         }
1640         /* FIXME: This will not restore zapped printk locks. */
1641         RESTORE_LOGLEVEL(console_loglevel);
1642         return NOTIFY_DONE;
1643 }
1644
1645 /*
1646  * C portion of the OS INIT handler
1647  *
1648  * Called from ia64_os_init_dispatch
1649  *
1650  * Inputs: pointer to pt_regs where processor info was saved.  SAL/OS state for
1651  * this event.  This code is used for both monarch and slave INIT events, see
1652  * sos->monarch.
1653  *
1654  * All INIT events switch to the INIT stack and change the previous process to
1655  * blocked status.  If one of the INIT events is the monarch then we are
1656  * probably processing the nmi button/command.  Use the monarch cpu to dump all
1657  * the processes.  The slave INIT events all spin until the monarch cpu
1658  * returns.  We can also get INIT slave events for MCA, in which case the MCA
1659  * process is the monarch.
1660  */
1661
1662 void
1663 ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
1664                   struct ia64_sal_os_state *sos)
1665 {
1666         static atomic_t slaves;
1667         static atomic_t monarchs;
1668         struct task_struct *previous_current;
1669         int cpu = smp_processor_id();
1670         struct ia64_mca_notify_die nd =
1671                 { .sos = sos, .monarch_cpu = &monarch_cpu };
1672
1673         NOTIFY_INIT(DIE_INIT_ENTER, regs, (long)&nd, 0);
1674
1675         mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
1676                 sos->proc_state_param, cpu, sos->monarch);
1677         salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
1678
1679         previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "INIT");
1680         sos->os_status = IA64_INIT_RESUME;
1681
1682         /* FIXME: Workaround for broken proms that drive all INIT events as
1683          * slaves.  The last slave that enters is promoted to be a monarch.
1684          * Remove this code in September 2006, that gives platforms a year to
1685          * fix their proms and get their customers updated.
1686          */
1687         if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
1688                 mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
1689                         __func__, cpu);
1690                 atomic_dec(&slaves);
1691                 sos->monarch = 1;
1692         }
1693
1694         /* FIXME: Workaround for broken proms that drive all INIT events as
1695          * monarchs.  Second and subsequent monarchs are demoted to slaves.
1696          * Remove this code in September 2006, that gives platforms a year to
1697          * fix their proms and get their customers updated.
1698          */
1699         if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
1700                 mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
1701                                __func__, cpu);
1702                 atomic_dec(&monarchs);
1703                 sos->monarch = 0;
1704         }
1705
1706         if (!sos->monarch) {
1707                 ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_INIT;
1708
1709 #ifdef CONFIG_KEXEC
1710                 while (monarch_cpu == -1 && !atomic_read(&kdump_in_progress))
1711                         udelay(1000);
1712 #else
1713                 while (monarch_cpu == -1)
1714                         cpu_relax();    /* spin until monarch enters */
1715 #endif
1716
1717                 NOTIFY_INIT(DIE_INIT_SLAVE_ENTER, regs, (long)&nd, 1);
1718                 NOTIFY_INIT(DIE_INIT_SLAVE_PROCESS, regs, (long)&nd, 1);
1719
1720 #ifdef CONFIG_KEXEC
1721                 while (monarch_cpu != -1 && !atomic_read(&kdump_in_progress))
1722                         udelay(1000);
1723 #else
1724                 while (monarch_cpu != -1)
1725                         cpu_relax();    /* spin until monarch leaves */
1726 #endif
1727
1728                 NOTIFY_INIT(DIE_INIT_SLAVE_LEAVE, regs, (long)&nd, 1);
1729
1730                 mprintk("Slave on cpu %d returning to normal service.\n", cpu);
1731                 ia64_set_curr_task(cpu, previous_current);
1732                 ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1733                 atomic_dec(&slaves);
1734                 return;
1735         }
1736
1737         monarch_cpu = cpu;
1738         NOTIFY_INIT(DIE_INIT_MONARCH_ENTER, regs, (long)&nd, 1);
1739
1740         /*
1741          * Wait for a bit.  On some machines (e.g., HP's zx2000 and zx6000, INIT can be
1742          * generated via the BMC's command-line interface, but since the console is on the
1743          * same serial line, the user will need some time to switch out of the BMC before
1744          * the dump begins.
1745          */
1746         mprintk("Delaying for 5 seconds...\n");
1747         udelay(5*1000000);
1748         ia64_wait_for_slaves(cpu, "INIT");
1749         /* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
1750          * to default_monarch_init_process() above and just print all the
1751          * tasks.
1752          */
1753         NOTIFY_INIT(DIE_INIT_MONARCH_PROCESS, regs, (long)&nd, 1);
1754         NOTIFY_INIT(DIE_INIT_MONARCH_LEAVE, regs, (long)&nd, 1);
1755
1756         mprintk("\nINIT dump complete.  Monarch on cpu %d returning to normal service.\n", cpu);
1757         atomic_dec(&monarchs);
1758         ia64_set_curr_task(cpu, previous_current);
1759         monarch_cpu = -1;
1760         return;
1761 }
1762
1763 static int __init
1764 ia64_mca_disable_cpe_polling(char *str)
1765 {
1766         cpe_poll_enabled = 0;
1767         return 1;
1768 }
1769
1770 __setup("disable_cpe_poll", ia64_mca_disable_cpe_polling);
1771
1772 /* Minimal format of the MCA/INIT stacks.  The pseudo processes that run on
1773  * these stacks can never sleep, they cannot return from the kernel to user
1774  * space, they do not appear in a normal ps listing.  So there is no need to
1775  * format most of the fields.
1776  */
1777
1778 static void
1779 format_mca_init_stack(void *mca_data, unsigned long offset,
1780                 const char *type, int cpu)
1781 {
1782         struct task_struct *p = (struct task_struct *)((char *)mca_data + offset);
1783         struct thread_info *ti;
1784         memset(p, 0, KERNEL_STACK_SIZE);
1785         ti = task_thread_info(p);
1786         ti->flags = _TIF_MCA_INIT;
1787         ti->preempt_count = 1;
1788         ti->task = p;
1789         ti->cpu = cpu;
1790         p->stack = ti;
1791         p->__state = TASK_UNINTERRUPTIBLE;
1792         cpumask_set_cpu(cpu, &p->cpus_mask);
1793         INIT_LIST_HEAD(&p->tasks);
1794         p->parent = p->real_parent = p->group_leader = p;
1795         INIT_LIST_HEAD(&p->children);
1796         INIT_LIST_HEAD(&p->sibling);
1797         strncpy(p->comm, type, sizeof(p->comm)-1);
1798 }
1799
1800 /* Caller prevents this from being called after init */
1801 static void * __ref mca_bootmem(void)
1802 {
1803         return memblock_alloc(sizeof(struct ia64_mca_cpu), KERNEL_STACK_SIZE);
1804 }
1805
1806 /* Do per-CPU MCA-related initialization.  */
1807 void
1808 ia64_mca_cpu_init(void *cpu_data)
1809 {
1810         void *pal_vaddr;
1811         void *data;
1812         long sz = sizeof(struct ia64_mca_cpu);
1813         int cpu = smp_processor_id();
1814         static int first_time = 1;
1815
1816         /*
1817          * Structure will already be allocated if cpu has been online,
1818          * then offlined.
1819          */
1820         if (__per_cpu_mca[cpu]) {
1821                 data = __va(__per_cpu_mca[cpu]);
1822         } else {
1823                 if (first_time) {
1824                         data = mca_bootmem();
1825                         first_time = 0;
1826                 } else
1827                         data = (void *)__get_free_pages(GFP_ATOMIC,
1828                                                         get_order(sz));
1829                 if (!data)
1830                         panic("Could not allocate MCA memory for cpu %d\n",
1831                                         cpu);
1832         }
1833         format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, mca_stack),
1834                 "MCA", cpu);
1835         format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, init_stack),
1836                 "INIT", cpu);
1837         __this_cpu_write(ia64_mca_data, (__per_cpu_mca[cpu] = __pa(data)));
1838
1839         /*
1840          * Stash away a copy of the PTE needed to map the per-CPU page.
1841          * We may need it during MCA recovery.
1842          */
1843         __this_cpu_write(ia64_mca_per_cpu_pte,
1844                 pte_val(mk_pte_phys(__pa(cpu_data), PAGE_KERNEL)));
1845
1846         /*
1847          * Also, stash away a copy of the PAL address and the PTE
1848          * needed to map it.
1849          */
1850         pal_vaddr = efi_get_pal_addr();
1851         if (!pal_vaddr)
1852                 return;
1853         __this_cpu_write(ia64_mca_pal_base,
1854                 GRANULEROUNDDOWN((unsigned long) pal_vaddr));
1855         __this_cpu_write(ia64_mca_pal_pte, pte_val(mk_pte_phys(__pa(pal_vaddr),
1856                                                               PAGE_KERNEL)));
1857 }
1858
1859 static int ia64_mca_cpu_online(unsigned int cpu)
1860 {
1861         unsigned long flags;
1862
1863         local_irq_save(flags);
1864         if (!cmc_polling_enabled)
1865                 ia64_mca_cmc_vector_enable(NULL);
1866         local_irq_restore(flags);
1867         return 0;
1868 }
1869
1870 /*
1871  * ia64_mca_init
1872  *
1873  *  Do all the system level mca specific initialization.
1874  *
1875  *      1. Register spinloop and wakeup request interrupt vectors
1876  *
1877  *      2. Register OS_MCA handler entry point
1878  *
1879  *      3. Register OS_INIT handler entry point
1880  *
1881  *  4. Initialize MCA/CMC/INIT related log buffers maintained by the OS.
1882  *
1883  *  Note that this initialization is done very early before some kernel
1884  *  services are available.
1885  *
1886  *  Inputs  :   None
1887  *
1888  *  Outputs :   None
1889  */
1890 void __init
1891 ia64_mca_init(void)
1892 {
1893         ia64_fptr_t *init_hldlr_ptr_monarch = (ia64_fptr_t *)ia64_os_init_dispatch_monarch;
1894         ia64_fptr_t *init_hldlr_ptr_slave = (ia64_fptr_t *)ia64_os_init_dispatch_slave;
1895         ia64_fptr_t *mca_hldlr_ptr = (ia64_fptr_t *)ia64_os_mca_dispatch;
1896         int i;
1897         long rc;
1898         struct ia64_sal_retval isrv;
1899         unsigned long timeout = IA64_MCA_RENDEZ_TIMEOUT; /* platform specific */
1900         static struct notifier_block default_init_monarch_nb = {
1901                 .notifier_call = default_monarch_init_process,
1902                 .priority = 0/* we need to notified last */
1903         };
1904
1905         IA64_MCA_DEBUG("%s: begin\n", __func__);
1906
1907         /* Clear the Rendez checkin flag for all cpus */
1908         for(i = 0 ; i < NR_CPUS; i++)
1909                 ia64_mc_info.imi_rendez_checkin[i] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
1910
1911         /*
1912          * Register the rendezvous spinloop and wakeup mechanism with SAL
1913          */
1914
1915         /* Register the rendezvous interrupt vector with SAL */
1916         while (1) {
1917                 isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_INT,
1918                                               SAL_MC_PARAM_MECHANISM_INT,
1919                                               IA64_MCA_RENDEZ_VECTOR,
1920                                               timeout,
1921                                               SAL_MC_PARAM_RZ_ALWAYS);
1922                 rc = isrv.status;
1923                 if (rc == 0)
1924                         break;
1925                 if (rc == -2) {
1926                         printk(KERN_INFO "Increasing MCA rendezvous timeout from "
1927                                 "%ld to %ld milliseconds\n", timeout, isrv.v0);
1928                         timeout = isrv.v0;
1929                         NOTIFY_MCA(DIE_MCA_NEW_TIMEOUT, NULL, timeout, 0);
1930                         continue;
1931                 }
1932                 printk(KERN_ERR "Failed to register rendezvous interrupt "
1933                        "with SAL (status %ld)\n", rc);
1934                 return;
1935         }
1936
1937         /* Register the wakeup interrupt vector with SAL */
1938         isrv = ia64_sal_mc_set_params(SAL_MC_PARAM_RENDEZ_WAKEUP,
1939                                       SAL_MC_PARAM_MECHANISM_INT,
1940                                       IA64_MCA_WAKEUP_VECTOR,
1941                                       0, 0);
1942         rc = isrv.status;
1943         if (rc) {
1944                 printk(KERN_ERR "Failed to register wakeup interrupt with SAL "
1945                        "(status %ld)\n", rc);
1946                 return;
1947         }
1948
1949         IA64_MCA_DEBUG("%s: registered MCA rendezvous spinloop and wakeup mech.\n", __func__);
1950
1951         ia64_mc_info.imi_mca_handler        = ia64_tpa(mca_hldlr_ptr->fp);
1952         /*
1953          * XXX - disable SAL checksum by setting size to 0; should be
1954          *      ia64_tpa(ia64_os_mca_dispatch_end) - ia64_tpa(ia64_os_mca_dispatch);
1955          */
1956         ia64_mc_info.imi_mca_handler_size       = 0;
1957
1958         /* Register the os mca handler with SAL */
1959         if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_MCA,
1960                                        ia64_mc_info.imi_mca_handler,
1961                                        ia64_tpa(mca_hldlr_ptr->gp),
1962                                        ia64_mc_info.imi_mca_handler_size,
1963                                        0, 0, 0)))
1964         {
1965                 printk(KERN_ERR "Failed to register OS MCA handler with SAL "
1966                        "(status %ld)\n", rc);
1967                 return;
1968         }
1969
1970         IA64_MCA_DEBUG("%s: registered OS MCA handler with SAL at 0x%lx, gp = 0x%lx\n", __func__,
1971                        ia64_mc_info.imi_mca_handler, ia64_tpa(mca_hldlr_ptr->gp));
1972
1973         /*
1974          * XXX - disable SAL checksum by setting size to 0, should be
1975          * size of the actual init handler in mca_asm.S.
1976          */
1977         ia64_mc_info.imi_monarch_init_handler           = ia64_tpa(init_hldlr_ptr_monarch->fp);
1978         ia64_mc_info.imi_monarch_init_handler_size      = 0;
1979         ia64_mc_info.imi_slave_init_handler             = ia64_tpa(init_hldlr_ptr_slave->fp);
1980         ia64_mc_info.imi_slave_init_handler_size        = 0;
1981
1982         IA64_MCA_DEBUG("%s: OS INIT handler at %lx\n", __func__,
1983                        ia64_mc_info.imi_monarch_init_handler);
1984
1985         /* Register the os init handler with SAL */
1986         if ((rc = ia64_sal_set_vectors(SAL_VECTOR_OS_INIT,
1987                                        ia64_mc_info.imi_monarch_init_handler,
1988                                        ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1989                                        ia64_mc_info.imi_monarch_init_handler_size,
1990                                        ia64_mc_info.imi_slave_init_handler,
1991                                        ia64_tpa(ia64_getreg(_IA64_REG_GP)),
1992                                        ia64_mc_info.imi_slave_init_handler_size)))
1993         {
1994                 printk(KERN_ERR "Failed to register m/s INIT handlers with SAL "
1995                        "(status %ld)\n", rc);
1996                 return;
1997         }
1998         if (register_die_notifier(&default_init_monarch_nb)) {
1999                 printk(KERN_ERR "Failed to register default monarch INIT process\n");
2000                 return;
2001         }
2002
2003         IA64_MCA_DEBUG("%s: registered OS INIT handler with SAL\n", __func__);
2004
2005         /* Initialize the areas set aside by the OS to buffer the
2006          * platform/processor error states for MCA/INIT/CMC
2007          * handling.
2008          */
2009         ia64_log_init(SAL_INFO_TYPE_MCA);
2010         ia64_log_init(SAL_INFO_TYPE_INIT);
2011         ia64_log_init(SAL_INFO_TYPE_CMC);
2012         ia64_log_init(SAL_INFO_TYPE_CPE);
2013
2014         mca_init = 1;
2015         printk(KERN_INFO "MCA related initialization done\n");
2016 }
2017
2018
2019 /*
2020  * These pieces cannot be done in ia64_mca_init() because it is called before
2021  * early_irq_init() which would wipe out our percpu irq registrations. But we
2022  * cannot leave them until ia64_mca_late_init() because by then all the other
2023  * processors have been brought online and have set their own CMC vectors to
2024  * point at a non-existant action. Called from arch_early_irq_init().
2025  */
2026 void __init ia64_mca_irq_init(void)
2027 {
2028         /*
2029          *  Configure the CMCI/P vector and handler. Interrupts for CMC are
2030          *  per-processor, so AP CMC interrupts are setup in smp_callin() (smpboot.c).
2031          */
2032         register_percpu_irq(IA64_CMC_VECTOR, ia64_mca_cmc_int_handler, 0,
2033                             "cmc_hndlr");
2034         register_percpu_irq(IA64_CMCP_VECTOR, ia64_mca_cmc_int_caller, 0,
2035                             "cmc_poll");
2036         ia64_mca_cmc_vector_setup();       /* Setup vector on BSP */
2037
2038         /* Setup the MCA rendezvous interrupt vector */
2039         register_percpu_irq(IA64_MCA_RENDEZ_VECTOR, ia64_mca_rendez_int_handler,
2040                             0, "mca_rdzv");
2041
2042         /* Setup the MCA wakeup interrupt vector */
2043         register_percpu_irq(IA64_MCA_WAKEUP_VECTOR, ia64_mca_wakeup_int_handler,
2044                             0, "mca_wkup");
2045
2046         /* Setup the CPEI/P handler */
2047         register_percpu_irq(IA64_CPEP_VECTOR, ia64_mca_cpe_int_caller, 0,
2048                             "cpe_poll");
2049 }
2050
2051 /*
2052  * ia64_mca_late_init
2053  *
2054  *      Opportunity to setup things that require initialization later
2055  *      than ia64_mca_init.  Setup a timer to poll for CPEs if the
2056  *      platform doesn't support an interrupt driven mechanism.
2057  *
2058  *  Inputs  :   None
2059  *  Outputs :   Status
2060  */
2061 static int __init
2062 ia64_mca_late_init(void)
2063 {
2064         if (!mca_init)
2065                 return 0;
2066
2067         /* Setup the CMCI/P vector and handler */
2068         timer_setup(&cmc_poll_timer, ia64_mca_cmc_poll, 0);
2069
2070         /* Unmask/enable the vector */
2071         cmc_polling_enabled = 0;
2072         cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/mca:online",
2073                           ia64_mca_cpu_online, NULL);
2074         IA64_MCA_DEBUG("%s: CMCI/P setup and enabled.\n", __func__);
2075
2076         /* Setup the CPEI/P vector and handler */
2077         cpe_vector = acpi_request_vector(ACPI_INTERRUPT_CPEI);
2078         timer_setup(&cpe_poll_timer, ia64_mca_cpe_poll, 0);
2079
2080         {
2081                 unsigned int irq;
2082
2083                 if (cpe_vector >= 0) {
2084                         /* If platform supports CPEI, enable the irq. */
2085                         irq = local_vector_to_irq(cpe_vector);
2086                         if (irq > 0) {
2087                                 cpe_poll_enabled = 0;
2088                                 irq_set_status_flags(irq, IRQ_PER_CPU);
2089                                 if (request_irq(irq, ia64_mca_cpe_int_handler,
2090                                                 0, "cpe_hndlr", NULL))
2091                                         pr_err("Failed to register cpe_hndlr interrupt\n");
2092                                 ia64_cpe_irq = irq;
2093                                 ia64_mca_register_cpev(cpe_vector);
2094                                 IA64_MCA_DEBUG("%s: CPEI/P setup and enabled.\n",
2095                                         __func__);
2096                                 return 0;
2097                         }
2098                         printk(KERN_ERR "%s: Failed to find irq for CPE "
2099                                         "interrupt handler, vector %d\n",
2100                                         __func__, cpe_vector);
2101                 }
2102                 /* If platform doesn't support CPEI, get the timer going. */
2103                 if (cpe_poll_enabled) {
2104                         ia64_mca_cpe_poll(0UL);
2105                         IA64_MCA_DEBUG("%s: CPEP setup and enabled.\n", __func__);
2106                 }
2107         }
2108
2109         return 0;
2110 }
2111
2112 device_initcall(ia64_mca_late_init);