release/src-rt-6.x.4708/linux/linux-2.6.36/arch/ia64/kernel/mca_drv.c

   1 /*
   2  * File:        mca_drv.c
   3  * Purpose:     Generic MCA handling layer
   4  *
   5  * Copyright (C) 2004 FUJITSU LIMITED
   6  * Copyright (C) 2004 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
   7  * Copyright (C) 2005 Silicon Graphics, Inc
   8  * Copyright (C) 2005 Keith Owens <kaos@sgi.com>
   9  * Copyright (C) 2006 Russ Anderson <rja@sgi.com>
  10  */
  11 #include <linux/types.h>
  12 #include <linux/init.h>
  13 #include <linux/sched.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/irq.h>
  16 #include <linux/kallsyms.h>
  17 #include <linux/bootmem.h>
  18 #include <linux/acpi.h>
  19 #include <linux/timer.h>
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/smp.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/mm.h>
  25 #include <linux/slab.h>
  26
  27 #include <asm/delay.h>
  28 #include <asm/machvec.h>
  29 #include <asm/page.h>
  30 #include <asm/ptrace.h>
  31 #include <asm/system.h>
  32 #include <asm/sal.h>
  33 #include <asm/mca.h>
  34
  35 #include <asm/irq.h>
  36 #include <asm/hw_irq.h>
  37
  38 #include "mca_drv.h"
  39
  40 /* max size of SAL error record (default) */
  41 static int sal_rec_max = 10000;
  42
  43 /* from mca_drv_asm.S */
  44 extern void *mca_handler_bhhook(void);
  45
  46 static DEFINE_SPINLOCK(mca_bh_lock);
  47
  48 typedef enum {
  49         MCA_IS_LOCAL  = 0,
  50         MCA_IS_GLOBAL = 1
  51 } mca_type_t;
  52
  53 #define MAX_PAGE_ISOLATE 1024
  54
  55 static struct page *page_isolate[MAX_PAGE_ISOLATE];
  56 static int num_page_isolate = 0;
  57
  58 typedef enum {
  59         ISOLATE_NG,
  60         ISOLATE_OK,
  61         ISOLATE_NONE
  62 } isolate_status_t;
  63
  64 typedef enum {
  65         MCA_NOT_RECOVERED = 0,
  66         MCA_RECOVERED     = 1
  67 } recovery_status_t;
  68
  69 /*
  70  *  This pool keeps pointers to the section part of SAL error record
  71  */
  72 static struct {
  73         slidx_list_t *buffer; /* section pointer list pool */
  74         int          cur_idx; /* Current index of section pointer list pool */
  75         int          max_idx; /* Maximum index of section pointer list pool */
  76 } slidx_pool;
  77
  78 static int
  79 fatal_mca(const char *fmt, ...)
  80 {
  81         va_list args;
  82         char buf[256];
  83
  84         va_start(args, fmt);
  85         vsnprintf(buf, sizeof(buf), fmt, args);
  86         va_end(args);
  87         ia64_mca_printk(KERN_ALERT "MCA: %s\n", buf);
  88
  89         return MCA_NOT_RECOVERED;
  90 }
  91
  92 static int
  93 mca_recovered(const char *fmt, ...)
  94 {
  95         va_list args;
  96         char buf[256];
  97
  98         va_start(args, fmt);
  99         vsnprintf(buf, sizeof(buf), fmt, args);
 100         va_end(args);
 101         ia64_mca_printk(KERN_INFO "MCA: %s\n", buf);
 102
 103         return MCA_RECOVERED;
 104 }
 105
 106 /**
 107  * mca_page_isolate - isolate a poisoned page in order not to use it later
 108  * @paddr:      poisoned memory location
 109  *
 110  * Return value:
 111  *      one of isolate_status_t, ISOLATE_OK/NG/NONE.
 112  */
 113
 114 static isolate_status_t
 115 mca_page_isolate(unsigned long paddr)
 116 {
 117         int i;
 118         struct page *p;
 119
 120         /* whether physical address is valid or not */
 121         if (!ia64_phys_addr_valid(paddr))
 122                 return ISOLATE_NONE;
 123
 124         if (!pfn_valid(paddr >> PAGE_SHIFT))
 125                 return ISOLATE_NONE;
 126
 127         /* convert physical address to physical page number */
 128         p = pfn_to_page(paddr>>PAGE_SHIFT);
 129
 130         /* check whether a page number have been already registered or not */
 131         for (i = 0; i < num_page_isolate; i++)
 132                 if (page_isolate[i] == p)
 133                         return ISOLATE_OK; /* already listed */
 134
 135         /* limitation check */
 136         if (num_page_isolate == MAX_PAGE_ISOLATE)
 137                 return ISOLATE_NG;
 138
 139         /* kick pages having attribute 'SLAB' or 'Reserved' */
 140         if (PageSlab(p) || PageReserved(p))
 141                 return ISOLATE_NG;
 142
 143         /* add attribute 'Reserved' and register the page */
 144         get_page(p);
 145         SetPageReserved(p);
 146         page_isolate[num_page_isolate++] = p;
 147
 148         return ISOLATE_OK;
 149 }
 150
 151 /**
 152  * mca_hanlder_bh - Kill the process which occurred memory read error
 153  * @paddr:      poisoned address received from MCA Handler
 154  */
 155
 156 void
 157 mca_handler_bh(unsigned long paddr, void *iip, unsigned long ipsr)
 158 {
 159         ia64_mlogbuf_dump();
 160         printk(KERN_ERR "OS_MCA: process [cpu %d, pid: %d, uid: %d, "
 161                 "iip: %p, psr: 0x%lx,paddr: 0x%lx](%s) encounters MCA.\n",
 162                raw_smp_processor_id(), current->pid, current_uid(),
 163                 iip, ipsr, paddr, current->comm);
 164
 165         spin_lock(&mca_bh_lock);
 166         switch (mca_page_isolate(paddr)) {
 167         case ISOLATE_OK:
 168                 printk(KERN_DEBUG "Page isolation: ( %lx ) success.\n", paddr);
 169                 break;
 170         case ISOLATE_NG:
 171                 printk(KERN_CRIT "Page isolation: ( %lx ) failure.\n", paddr);
 172                 break;
 173         default:
 174                 break;
 175         }
 176         spin_unlock(&mca_bh_lock);
 177
 178         /* This process is about to be killed itself */
 179         do_exit(SIGKILL);
 180 }
 181
 182 /**
 183  * mca_make_peidx - Make index of processor error section
 184  * @slpi:       pointer to record of processor error section
 185  * @peidx:      pointer to index of processor error section
 186  */
 187
 188 static void
 189 mca_make_peidx(sal_log_processor_info_t *slpi, peidx_table_t *peidx)
 190 {
 191         /*
 192          * calculate the start address of
 193          *   "struct cpuid_info" and "sal_processor_static_info_t".
 194          */
 195         u64 total_check_num = slpi->valid.num_cache_check
 196                                 + slpi->valid.num_tlb_check
 197                                 + slpi->valid.num_bus_check
 198                                 + slpi->valid.num_reg_file_check
 199                                 + slpi->valid.num_ms_check;
 200         u64 head_size = sizeof(sal_log_mod_error_info_t) * total_check_num
 201                         + sizeof(sal_log_processor_info_t);
 202         u64 mid_size  = slpi->valid.cpuid_info * sizeof(struct sal_cpuid_info);
 203
 204         peidx_head(peidx)   = slpi;
 205         peidx_mid(peidx)    = (struct sal_cpuid_info *)
 206                 (slpi->valid.cpuid_info ? ((char*)slpi + head_size) : NULL);
 207         peidx_bottom(peidx) = (sal_processor_static_info_t *)
 208                 (slpi->valid.psi_static_struct ?
 209                         ((char*)slpi + head_size + mid_size) : NULL);
 210 }
 211
 212 /**
 213  * mca_make_slidx -  Make index of SAL error record
 214  * @buffer:     pointer to SAL error record
 215  * @slidx:      pointer to index of SAL error record
 216  *
 217  * Return value:
 218  *      1 if record has platform error / 0 if not
 219  */
 220 #define LOG_INDEX_ADD_SECT_PTR(sect, ptr) \
 221         {slidx_list_t *hl = &slidx_pool.buffer[slidx_pool.cur_idx]; \
 222         hl->hdr = ptr; \
 223         list_add(&hl->list, &(sect)); \
 224         slidx_pool.cur_idx = (slidx_pool.cur_idx + 1)%slidx_pool.max_idx; }
 225
 226 static int
 227 mca_make_slidx(void *buffer, slidx_table_t *slidx)
 228 {
 229         int platform_err = 0;
 230         int record_len = ((sal_log_record_header_t*)buffer)->len;
 231         u32 ercd_pos;
 232         int sects;
 233         sal_log_section_hdr_t *sp;
 234
 235         /*
 236          * Initialize index referring current record
 237          */
 238         INIT_LIST_HEAD(&(slidx->proc_err));
 239         INIT_LIST_HEAD(&(slidx->mem_dev_err));
 240         INIT_LIST_HEAD(&(slidx->sel_dev_err));
 241         INIT_LIST_HEAD(&(slidx->pci_bus_err));
 242         INIT_LIST_HEAD(&(slidx->smbios_dev_err));
 243         INIT_LIST_HEAD(&(slidx->pci_comp_err));
 244         INIT_LIST_HEAD(&(slidx->plat_specific_err));
 245         INIT_LIST_HEAD(&(slidx->host_ctlr_err));
 246         INIT_LIST_HEAD(&(slidx->plat_bus_err));
 247         INIT_LIST_HEAD(&(slidx->unsupported));
 248
 249         /*
 250          * Extract a Record Header
 251          */
 252         slidx->header = buffer;
 253
 254         /*
 255          * Extract each section records
 256          * (arranged from "int ia64_log_platform_info_print()")
 257          */
 258         for (ercd_pos = sizeof(sal_log_record_header_t), sects = 0;
 259                 ercd_pos < record_len; ercd_pos += sp->len, sects++) {
 260                 sp = (sal_log_section_hdr_t *)((char*)buffer + ercd_pos);
 261                 if (!efi_guidcmp(sp->guid, SAL_PROC_DEV_ERR_SECT_GUID)) {
 262                         LOG_INDEX_ADD_SECT_PTR(slidx->proc_err, sp);
 263                 } else if (!efi_guidcmp(sp->guid,
 264                                 SAL_PLAT_MEM_DEV_ERR_SECT_GUID)) {
 265                         platform_err = 1;
 266                         LOG_INDEX_ADD_SECT_PTR(slidx->mem_dev_err, sp);
 267                 } else if (!efi_guidcmp(sp->guid,
 268                                 SAL_PLAT_SEL_DEV_ERR_SECT_GUID)) {
 269                         platform_err = 1;
 270                         LOG_INDEX_ADD_SECT_PTR(slidx->sel_dev_err, sp);
 271                 } else if (!efi_guidcmp(sp->guid,
 272                                 SAL_PLAT_PCI_BUS_ERR_SECT_GUID)) {
 273                         platform_err = 1;
 274                         LOG_INDEX_ADD_SECT_PTR(slidx->pci_bus_err, sp);
 275                 } else if (!efi_guidcmp(sp->guid,
 276                                 SAL_PLAT_SMBIOS_DEV_ERR_SECT_GUID)) {
 277                         platform_err = 1;
 278                         LOG_INDEX_ADD_SECT_PTR(slidx->smbios_dev_err, sp);
 279                 } else if (!efi_guidcmp(sp->guid,
 280                                 SAL_PLAT_PCI_COMP_ERR_SECT_GUID)) {
 281                         platform_err = 1;
 282                         LOG_INDEX_ADD_SECT_PTR(slidx->pci_comp_err, sp);
 283                 } else if (!efi_guidcmp(sp->guid,
 284                                 SAL_PLAT_SPECIFIC_ERR_SECT_GUID)) {
 285                         platform_err = 1;
 286                         LOG_INDEX_ADD_SECT_PTR(slidx->plat_specific_err, sp);
 287                 } else if (!efi_guidcmp(sp->guid,
 288                                 SAL_PLAT_HOST_CTLR_ERR_SECT_GUID)) {
 289                         platform_err = 1;
 290                         LOG_INDEX_ADD_SECT_PTR(slidx->host_ctlr_err, sp);
 291                 } else if (!efi_guidcmp(sp->guid,
 292                                 SAL_PLAT_BUS_ERR_SECT_GUID)) {
 293                         platform_err = 1;
 294                         LOG_INDEX_ADD_SECT_PTR(slidx->plat_bus_err, sp);
 295                 } else {
 296                         LOG_INDEX_ADD_SECT_PTR(slidx->unsupported, sp);
 297                 }
 298         }
 299         slidx->n_sections = sects;
 300
 301         return platform_err;
 302 }
 303
 304 /**
 305  * init_record_index_pools - Initialize pool of lists for SAL record index
 306  *
 307  * Return value:
 308  *      0 on Success / -ENOMEM on Failure
 309  */
 310 static int
 311 init_record_index_pools(void)
 312 {
 313         int i;
 314         int rec_max_size;  /* Maximum size of SAL error records */
 315         int sect_min_size; /* Minimum size of SAL error sections */
 316         /* minimum size table of each section */
 317         static int sal_log_sect_min_sizes[] = {
 318                 sizeof(sal_log_processor_info_t)
 319                 + sizeof(sal_processor_static_info_t),
 320                 sizeof(sal_log_mem_dev_err_info_t),
 321                 sizeof(sal_log_sel_dev_err_info_t),
 322                 sizeof(sal_log_pci_bus_err_info_t),
 323                 sizeof(sal_log_smbios_dev_err_info_t),
 324                 sizeof(sal_log_pci_comp_err_info_t),
 325                 sizeof(sal_log_plat_specific_err_info_t),
 326                 sizeof(sal_log_host_ctlr_err_info_t),
 327                 sizeof(sal_log_plat_bus_err_info_t),
 328         };
 329
 330         /*
 331          * MCA handler cannot allocate new memory on flight,
 332          * so we preallocate enough memory to handle a SAL record.
 333          *
 334          * Initialize a handling set of slidx_pool:
 335          *   1. Pick up the max size of SAL error records
 336          *   2. Pick up the min size of SAL error sections
 337          *   3. Allocate the pool as enough to 2 SAL records
 338          *     (now we can estimate the maxinum of section in a record.)
 339          */
 340
 341         /* - 1 - */
 342         rec_max_size = sal_rec_max;
 343
 344         /* - 2 - */
 345         sect_min_size = sal_log_sect_min_sizes[0];
 346         for (i = 1; i < sizeof sal_log_sect_min_sizes/sizeof(size_t); i++)
 347                 if (sect_min_size > sal_log_sect_min_sizes[i])
 348                         sect_min_size = sal_log_sect_min_sizes[i];
 349
 350         /* - 3 - */
 351         slidx_pool.max_idx = (rec_max_size/sect_min_size) * 2 + 1;
 352         slidx_pool.buffer = (slidx_list_t *)
 353                 kmalloc(slidx_pool.max_idx * sizeof(slidx_list_t), GFP_KERNEL);
 354
 355         return slidx_pool.buffer ? 0 : -ENOMEM;
 356 }
 357
 358
 359 /*****************************************************************************
 360  * Recovery functions                                                        *
 361  *****************************************************************************/
 362
 363 /**
 364  * is_mca_global - Check whether this MCA is global or not
 365  * @peidx:      pointer of index of processor error section
 366  * @pbci:       pointer to pal_bus_check_info_t
 367  * @sos:        pointer to hand off struct between SAL and OS
 368  *
 369  * Return value:
 370  *      MCA_IS_LOCAL / MCA_IS_GLOBAL
 371  */
 372
 373 static mca_type_t
 374 is_mca_global(peidx_table_t *peidx, pal_bus_check_info_t *pbci,
 375               struct ia64_sal_os_state *sos)
 376 {
 377         pal_processor_state_info_t *psp =
 378                 (pal_processor_state_info_t*)peidx_psp(peidx);
 379
 380         /*
 381          * PAL can request a rendezvous, if the MCA has a global scope.
 382          * If "rz_always" flag is set, SAL requests MCA rendezvous
 383          * in spite of global MCA.
 384          * Therefore it is local MCA when rendezvous has not been requested.
 385          * Failed to rendezvous, the system must be down.
 386          */
 387         switch (sos->rv_rc) {
 388                 case -1: /* SAL rendezvous unsuccessful */
 389                         return MCA_IS_GLOBAL;
 390                 case  0: /* SAL rendezvous not required */
 391                         return MCA_IS_LOCAL;
 392                 case  1: /* SAL rendezvous successful int */
 393                 case  2: /* SAL rendezvous successful int with init */
 394                 default:
 395                         break;
 396         }
 397
 398         /*
 399          * If One or more Cache/TLB/Reg_File/Uarch_Check is here,
 400          * it would be a local MCA. (i.e. processor internal error)
 401          */
 402         if (psp->tc || psp->cc || psp->rc || psp->uc)
 403                 return MCA_IS_LOCAL;
 404
 405         /*
 406          * Bus_Check structure with Bus_Check.ib (internal bus error) flag set
 407          * would be a global MCA. (e.g. a system bus address parity error)
 408          */
 409         if (!pbci || pbci->ib)
 410                 return MCA_IS_GLOBAL;
 411
 412         if (pbci->eb)
 413                 switch (pbci->bsi) {
 414                         case 0:
 415                                 /* e.g. a load from poisoned memory */
 416                                 return MCA_IS_LOCAL;
 417                         case 1:
 418                         case 2:
 419                         case 3:
 420                                 return MCA_IS_GLOBAL;
 421                 }
 422
 423         return MCA_IS_GLOBAL;
 424 }
 425
 426 /**
 427  * get_target_identifier - Get the valid Cache or Bus check target identifier.
 428  * @peidx:      pointer of index of processor error section
 429  *
 430  * Return value:
 431  *      target address on Success / 0 on Failure
 432  */
 433 static u64
 434 get_target_identifier(peidx_table_t *peidx)
 435 {
 436         u64 target_address = 0;
 437         sal_log_mod_error_info_t *smei;
 438         pal_cache_check_info_t *pcci;
 439         int i, level = 9;
 440
 441         /*
 442          * Look through the cache checks for a valid target identifier
 443          * If more than one valid target identifier, return the one
 444          * with the lowest cache level.
 445          */
 446         for (i = 0; i < peidx_cache_check_num(peidx); i++) {
 447                 smei = (sal_log_mod_error_info_t *)peidx_cache_check(peidx, i);
 448                 if (smei->valid.target_identifier && smei->target_identifier) {
 449                         pcci = (pal_cache_check_info_t *)&(smei->check_info);
 450                         if (!target_address || (pcci->level < level)) {
 451                                 target_address = smei->target_identifier;
 452                                 level = pcci->level;
 453                                 continue;
 454                         }
 455                 }
 456         }
 457         if (target_address)
 458                 return target_address;
 459
 460         /*
 461          * Look at the bus check for a valid target identifier
 462          */
 463         smei = peidx_bus_check(peidx, 0);
 464         if (smei && smei->valid.target_identifier)
 465                 return smei->target_identifier;
 466
 467         return 0;
 468 }
 469
 470 /**
 471  * recover_from_read_error - Try to recover the errors which type are "read"s.
 472  * @slidx:      pointer of index of SAL error record
 473  * @peidx:      pointer of index of processor error section
 474  * @pbci:       pointer of pal_bus_check_info
 475  * @sos:        pointer to hand off struct between SAL and OS
 476  *
 477  * Return value:
 478  *      1 on Success / 0 on Failure
 479  */
 480
 481 static int
 482 recover_from_read_error(slidx_table_t *slidx,
 483                         peidx_table_t *peidx, pal_bus_check_info_t *pbci,
 484                         struct ia64_sal_os_state *sos)
 485 {
 486         u64 target_identifier;
 487         pal_min_state_area_t *pmsa;
 488         struct ia64_psr *psr1, *psr2;
 489         ia64_fptr_t *mca_hdlr_bh = (ia64_fptr_t*)mca_handler_bhhook;
 490
 491         /* Is target address valid? */
 492         target_identifier = get_target_identifier(peidx);
 493         if (!target_identifier)
 494                 return fatal_mca("target address not valid");
 495
 496         /*
 497          * cpu read or memory-mapped io read
 498          *
 499          *    offending process  affected process  OS MCA do
 500          *     kernel mode        kernel mode       down system
 501          *     kernel mode        user   mode       kill the process
 502          *     user   mode        kernel mode       down system (*)
 503          *     user   mode        user   mode       kill the process
 504          *
 505          * (*) You could terminate offending user-mode process
 506          *    if (pbci->pv && pbci->pl != 0) *and* if you sure
 507          *    the process not have any locks of kernel.
 508          */
 509
 510         /* Is minstate valid? */
 511         if (!peidx_bottom(peidx) || !(peidx_bottom(peidx)->valid.minstate))
 512                 return fatal_mca("minstate not valid");
 513         psr1 =(struct ia64_psr *)&(peidx_minstate_area(peidx)->pmsa_ipsr);
 514         psr2 =(struct ia64_psr *)&(peidx_minstate_area(peidx)->pmsa_xpsr);
 515
 516         /*
 517          *  Check the privilege level of interrupted context.
 518          *   If it is user-mode, then terminate affected process.
 519          */
 520
 521         pmsa = sos->pal_min_state;
 522         if (psr1->cpl != 0 ||
 523            ((psr2->cpl != 0) && mca_recover_range(pmsa->pmsa_iip))) {
 524                 /*
 525                  *  setup for resume to bottom half of MCA,
 526                  * "mca_handler_bhhook"
 527                  */
 528                 /* pass to bhhook as argument (gr8, ...) */
 529                 pmsa->pmsa_gr[8-1] = target_identifier;
 530                 pmsa->pmsa_gr[9-1] = pmsa->pmsa_iip;
 531                 pmsa->pmsa_gr[10-1] = pmsa->pmsa_ipsr;
 532                 /* set interrupted return address (but no use) */
 533                 pmsa->pmsa_br0 = pmsa->pmsa_iip;
 534                 /* change resume address to bottom half */
 535                 pmsa->pmsa_iip = mca_hdlr_bh->fp;
 536                 pmsa->pmsa_gr[1-1] = mca_hdlr_bh->gp;
 537                 /* set cpl with kernel mode */
 538                 psr2 = (struct ia64_psr *)&pmsa->pmsa_ipsr;
 539                 psr2->cpl = 0;
 540                 psr2->ri  = 0;
 541                 psr2->bn  = 1;
 542                 psr2->i  = 0;
 543
 544                 return mca_recovered("user memory corruption. "
 545                                 "kill affected process - recovered.");
 546         }
 547
 548         return fatal_mca("kernel context not recovered, iip 0x%lx\n",
 549                          pmsa->pmsa_iip);
 550 }
 551
 552 /**
 553  * recover_from_platform_error - Recover from platform error.
 554  * @slidx:      pointer of index of SAL error record
 555  * @peidx:      pointer of index of processor error section
 556  * @pbci:       pointer of pal_bus_check_info
 557  * @sos:        pointer to hand off struct between SAL and OS
 558  *
 559  * Return value:
 560  *      1 on Success / 0 on Failure
 561  */
 562
 563 static int
 564 recover_from_platform_error(slidx_table_t *slidx, peidx_table_t *peidx,
 565                             pal_bus_check_info_t *pbci,
 566                             struct ia64_sal_os_state *sos)
 567 {
 568         int status = 0;
 569         pal_processor_state_info_t *psp =
 570                 (pal_processor_state_info_t*)peidx_psp(peidx);
 571
 572         if (psp->bc && pbci->eb && pbci->bsi == 0) {
 573                 switch(pbci->type) {
 574                 case 1: /* partial read */
 575                 case 3: /* full line(cpu) read */
 576                 case 9: /* I/O space read */
 577                         status = recover_from_read_error(slidx, peidx, pbci,
 578                                                          sos);
 579                         break;
 580                 case 0: /* unknown */
 581                 case 2: /* partial write */
 582                 case 4: /* full line write */
 583                 case 5: /* implicit or explicit write-back operation */
 584                 case 6: /* snoop probe */
 585                 case 7: /* incoming or outgoing ptc.g */
 586                 case 8: /* write coalescing transactions */
 587                 case 10: /* I/O space write */
 588                 case 11: /* inter-processor interrupt message(IPI) */
 589                 case 12: /* interrupt acknowledge or
 590                                 external task priority cycle */
 591                 default:
 592                         break;
 593                 }
 594         } else if (psp->cc && !psp->bc) {       /* Cache error */
 595                 status = recover_from_read_error(slidx, peidx, pbci, sos);
 596         }
 597
 598         return status;
 599 }
 600
 601 /*
 602  * recover_from_tlb_check
 603  * @peidx:      pointer of index of processor error section
 604  *
 605  * Return value:
 606  *      1 on Success / 0 on Failure
 607  */
 608 static int
 609 recover_from_tlb_check(peidx_table_t *peidx)
 610 {
 611         sal_log_mod_error_info_t *smei;
 612         pal_tlb_check_info_t *ptci;
 613
 614         smei = (sal_log_mod_error_info_t *)peidx_tlb_check(peidx, 0);
 615         ptci = (pal_tlb_check_info_t *)&(smei->check_info);
 616
 617         /*
 618          * Look for signature of a duplicate TLB DTC entry, which is
 619          * a SW bug and always fatal.
 620          */
 621         if (ptci->op == PAL_TLB_CHECK_OP_PURGE
 622             && !(ptci->itr || ptci->dtc || ptci->itc))
 623                 return fatal_mca("Duplicate TLB entry");
 624
 625         return mca_recovered("TLB check recovered");
 626 }
 627
 628 /**
 629  * recover_from_processor_error
 630  * @platform:   whether there are some platform error section or not
 631  * @slidx:      pointer of index of SAL error record
 632  * @peidx:      pointer of index of processor error section
 633  * @pbci:       pointer of pal_bus_check_info
 634  * @sos:        pointer to hand off struct between SAL and OS
 635  *
 636  * Return value:
 637  *      1 on Success / 0 on Failure
 638  */
 639
 640 static int
 641 recover_from_processor_error(int platform, slidx_table_t *slidx,
 642                              peidx_table_t *peidx, pal_bus_check_info_t *pbci,
 643                              struct ia64_sal_os_state *sos)
 644 {
 645         pal_processor_state_info_t *psp =
 646                 (pal_processor_state_info_t*)peidx_psp(peidx);
 647
 648         /*
 649          * Processor recovery status must key off of the PAL recovery
 650          * status in the Processor State Parameter.
 651          */
 652
 653         /*
 654          * The machine check is corrected.
 655          */
 656         if (psp->cm == 1)
 657                 return mca_recovered("machine check is already corrected.");
 658
 659         /*
 660          * The error was not contained.  Software must be reset.
 661          */
 662         if (psp->us || psp->ci == 0)
 663                 return fatal_mca("error not contained");
 664
 665         /*
 666          * Look for recoverable TLB check
 667          */
 668         if (psp->tc && !(psp->cc || psp->bc || psp->rc || psp->uc))
 669                 return recover_from_tlb_check(peidx);
 670
 671         /*
 672          * The cache check and bus check bits have four possible states
 673          *   cc bc
 674          *    1  1      Memory error, attempt recovery
 675          *    1  0      Cache error, attempt recovery
 676          *    0  1      I/O error, attempt recovery
 677          *    0  0      Other error type, not recovered
 678          */
 679         if (psp->cc == 0 && (psp->bc == 0 || pbci == NULL))
 680                 return fatal_mca("No cache or bus check");
 681
 682         /*
 683          * Cannot handle more than one bus check.
 684          */
 685         if (peidx_bus_check_num(peidx) > 1)
 686                 return fatal_mca("Too many bus checks");
 687
 688         if (pbci->ib)
 689                 return fatal_mca("Internal Bus error");
 690         if (pbci->eb && pbci->bsi > 0)
 691                 return fatal_mca("External bus check fatal status");
 692
 693         /*
 694          * This is a local MCA and estimated as a recoverable error.
 695          */
 696         if (platform)
 697                 return recover_from_platform_error(slidx, peidx, pbci, sos);
 698
 699         /*
 700          * On account of strange SAL error record, we cannot recover.
 701          */
 702         return fatal_mca("Strange SAL record");
 703 }
 704
 705 /**
 706  * mca_try_to_recover - Try to recover from MCA
 707  * @rec:        pointer to a SAL error record
 708  * @sos:        pointer to hand off struct between SAL and OS
 709  *
 710  * Return value:
 711  *      1 on Success / 0 on Failure
 712  */
 713
 714 static int
 715 mca_try_to_recover(void *rec, struct ia64_sal_os_state *sos)
 716 {
 717         int platform_err;
 718         int n_proc_err;
 719         slidx_table_t slidx;
 720         peidx_table_t peidx;
 721         pal_bus_check_info_t pbci;
 722
 723         /* Make index of SAL error record */
 724         platform_err = mca_make_slidx(rec, &slidx);
 725
 726         /* Count processor error sections */
 727         n_proc_err = slidx_count(&slidx, proc_err);
 728
 729          /* Now, OS can recover when there is one processor error section */
 730         if (n_proc_err > 1)
 731                 return fatal_mca("Too Many Errors");
 732         else if (n_proc_err == 0)
 733                 /* Weird SAL record ... We can't do anything */
 734                 return fatal_mca("Weird SAL record");
 735
 736         /* Make index of processor error section */
 737         mca_make_peidx((sal_log_processor_info_t*)
 738                 slidx_first_entry(&slidx.proc_err)->hdr, &peidx);
 739
 740         /* Extract Processor BUS_CHECK[0] */
 741         *((u64*)&pbci) = peidx_check_info(&peidx, bus_check, 0);
 742
 743         /* Check whether MCA is global or not */
 744         if (is_mca_global(&peidx, &pbci, sos))
 745                 return fatal_mca("global MCA");
 746
 747         /* Try to recover a processor error */
 748         return recover_from_processor_error(platform_err, &slidx, &peidx,
 749                                             &pbci, sos);
 750 }
 751
 752 /*
 753  * =============================================================================
 754  */
 755
 756 int __init mca_external_handler_init(void)
 757 {
 758         if (init_record_index_pools())
 759                 return -ENOMEM;
 760
 761         /* register external mca handlers */
 762         if (ia64_reg_MCA_extension(mca_try_to_recover)) {
 763                 printk(KERN_ERR "ia64_reg_MCA_extension failed.\n");
 764                 kfree(slidx_pool.buffer);
 765                 return -EFAULT;
 766         }
 767         return 0;
 768 }
 769
 770 void __exit mca_external_handler_exit(void)
 771 {
 772         /* unregister external mca handlers */
 773         ia64_unreg_MCA_extension();
 774         kfree(slidx_pool.buffer);
 775 }
 776
 777 module_init(mca_external_handler_init);
 778 module_exit(mca_external_handler_exit);
 779
 780 module_param(sal_rec_max, int, 0644);
 781 MODULE_PARM_DESC(sal_rec_max, "Max size of SAL error record");
 782
 783 MODULE_DESCRIPTION("ia64 platform dependent mca handler driver");
 784 MODULE_LICENSE("GPL");