arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "arch/i386/kernel/setup.c"
  10  *    Copyright (C) 1995, Linus Torvalds
  11  */
  12
  13 /*
  14  * This file handles the architecture-dependent parts of initialization
  15  */
  16
  17 #include <linux/errno.h>
  18 #include <linux/module.h>
  19 #include <linux/sched.h>
  20 #include <linux/kernel.h>
  21 #include <linux/mm.h>
  22 #include <linux/stddef.h>
  23 #include <linux/unistd.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/slab.h>
  26 #include <linux/user.h>
  27 #include <linux/a.out.h>
  28 #include <linux/tty.h>
  29 #include <linux/ioport.h>
  30 #include <linux/delay.h>
  31 #include <linux/config.h>
  32 #include <linux/init.h>
  33 #include <linux/initrd.h>
  34 #include <linux/bootmem.h>
  35 #include <linux/root_dev.h>
  36 #include <linux/console.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/kernel_stat.h>
  39
  40 #include <asm/uaccess.h>
  41 #include <asm/system.h>
  42 #include <asm/smp.h>
  43 #include <asm/mmu_context.h>
  44 #include <asm/cpcmd.h>
  45 #include <asm/lowcore.h>
  46 #include <asm/irq.h>
  47
  48 /*
  49  * Machine setup..
  50  */
  51 unsigned int console_mode = 0;
  52 unsigned int console_device = -1;
  53 unsigned int console_irq = -1;
  54 unsigned long memory_size = 0;
  55 unsigned long machine_flags = 0;
  56 struct {
  57         unsigned long addr, size, type;
  58 } memory_chunk[MEMORY_CHUNKS] = { { 0 } };
  59 #define CHUNK_READ_WRITE 0
  60 #define CHUNK_READ_ONLY 1
  61 int cpus_initialized = 0;
  62 static cpumask_t cpu_initialized;
  63 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
  64
  65 /*
  66  * Setup options
  67  */
  68 extern int _text,_etext, _edata, _end;
  69
  70 /*
  71  * This is set up by the setup-routine at boot-time
  72  * for S390 need to find out, what we have to setup
  73  * using address 0x10400 ...
  74  */
  75
  76 #include <asm/setup.h>
  77
  78 static char command_line[COMMAND_LINE_SIZE] = { 0, };
  79        char saved_command_line[COMMAND_LINE_SIZE];
  80
  81 static struct resource code_resource = { "Kernel code", 0x100000, 0 };
  82 static struct resource data_resource = { "Kernel data", 0, 0 };
  83
  84 /*
  85  * cpu_init() initializes state that is per-CPU.
  86  */
  87 void __devinit cpu_init (void)
  88 {
  89         int nr = smp_processor_id();
  90         int addr = hard_smp_processor_id();
  91
  92         if (cpu_test_and_set(nr,cpu_initialized)) {
  93                 printk("CPU#%d ALREADY INITIALIZED!!!!!!!!!\n", nr);
  94                 for (;;) local_irq_enable();
  95         }
  96         cpus_initialized++;
  97
  98         /*
  99          * Store processor id in lowcore (used e.g. in timer_interrupt)
 100          */
 101         asm volatile ("stidp %0": "=m" (S390_lowcore.cpu_data.cpu_id));
 102         S390_lowcore.cpu_data.cpu_addr = addr;
 103
 104         /*
 105          * Force FPU initialization:
 106          */
 107         clear_thread_flag(TIF_USEDFPU);
 108         current->used_math = 0;
 109
 110         /* Setup active_mm for idle_task  */
 111         atomic_inc(&init_mm.mm_count);
 112         current->active_mm = &init_mm;
 113         if (current->mm)
 114                 BUG();
 115         enter_lazy_tlb(&init_mm, current);
 116 }
 117
 118 /*
 119  * VM halt and poweroff setup routines
 120  */
 121 char vmhalt_cmd[128] = "";
 122 char vmpoff_cmd[128] = "";
 123
 124 static inline void strncpy_skip_quote(char *dst, char *src, int n)
 125 {
 126         int sx, dx;
 127
 128         dx = 0;
 129         for (sx = 0; src[sx] != 0; sx++) {
 130                 if (src[sx] == '"') continue;
 131                 dst[dx++] = src[sx];
 132                 if (dx >= n) break;
 133         }
 134 }
 135
 136 static int __init vmhalt_setup(char *str)
 137 {
 138         strncpy_skip_quote(vmhalt_cmd, str, 127);
 139         vmhalt_cmd[127] = 0;
 140         return 1;
 141 }
 142
 143 __setup("vmhalt=", vmhalt_setup);
 144
 145 static int __init vmpoff_setup(char *str)
 146 {
 147         strncpy_skip_quote(vmpoff_cmd, str, 127);
 148         vmpoff_cmd[127] = 0;
 149         return 1;
 150 }
 151
 152 __setup("vmpoff=", vmpoff_setup);
 153
 154 /*
 155  * condev= and conmode= setup parameter.
 156  */
 157
 158 static int __init condev_setup(char *str)
 159 {
 160         int vdev;
 161
 162         vdev = simple_strtoul(str, &str, 0);
 163         if (vdev >= 0 && vdev < 65536) {
 164                 console_device = vdev;
 165                 console_irq = -1;
 166         }
 167         return 1;
 168 }
 169
 170 __setup("condev=", condev_setup);
 171
 172 static int __init conmode_setup(char *str)
 173 {
 174 #if defined(CONFIG_SCLP_CONSOLE)
 175         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 176                 SET_CONSOLE_SCLP;
 177 #endif
 178 #if defined(CONFIG_TN3215_CONSOLE)
 179         if (strncmp(str, "3215", 5) == 0)
 180                 SET_CONSOLE_3215;
 181 #endif
 182 #if defined(CONFIG_TN3270_CONSOLE)
 183         if (strncmp(str, "3270", 5) == 0)
 184                 SET_CONSOLE_3270;
 185 #endif
 186         return 1;
 187 }
 188
 189 __setup("conmode=", conmode_setup);
 190
 191 static void __init conmode_default(void)
 192 {
 193         char query_buffer[1024];
 194         char *ptr;
 195
 196         if (MACHINE_IS_VM) {
 197                 cpcmd("QUERY CONSOLE", query_buffer, 1024);
 198                 console_device = simple_strtoul(query_buffer + 5, NULL, 16);
 199                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 200                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 201                 cpcmd("QUERY TERM", query_buffer, 1024);
 202                 ptr = strstr(query_buffer, "CONMODE");
 203                 /*
 204                  * Set the conmode to 3215 so that the device recognition
 205                  * will set the cu_type of the console to 3215. If the
 206                  * conmode is 3270 and we don't set it back then both
 207                  * 3215 and the 3270 driver will try to access the console
 208                  * device (3215 as console and 3270 as normal tty).
 209                  */
 210                 cpcmd("TERM CONMODE 3215", NULL, 0);
 211                 if (ptr == NULL) {
 212 #if defined(CONFIG_SCLP_CONSOLE)
 213                         SET_CONSOLE_SCLP;
 214 #endif
 215                         return;
 216                 }
 217                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 218 #if defined(CONFIG_TN3270_CONSOLE)
 219                         SET_CONSOLE_3270;
 220 #elif defined(CONFIG_TN3215_CONSOLE)
 221                         SET_CONSOLE_3215;
 222 #elif defined(CONFIG_SCLP_CONSOLE)
 223                         SET_CONSOLE_SCLP;
 224 #endif
 225                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 226 #if defined(CONFIG_TN3215_CONSOLE)
 227                         SET_CONSOLE_3215;
 228 #elif defined(CONFIG_TN3270_CONSOLE)
 229                         SET_CONSOLE_3270;
 230 #elif defined(CONFIG_SCLP_CONSOLE)
 231                         SET_CONSOLE_SCLP;
 232 #endif
 233                 }
 234         } else if (MACHINE_IS_P390) {
 235 #if defined(CONFIG_TN3215_CONSOLE)
 236                 SET_CONSOLE_3215;
 237 #elif defined(CONFIG_TN3270_CONSOLE)
 238                 SET_CONSOLE_3270;
 239 #endif
 240         } else {
 241 #if defined(CONFIG_SCLP_CONSOLE)
 242                 SET_CONSOLE_SCLP;
 243 #endif
 244         }
 245 }
 246
 247 #ifdef CONFIG_SMP
 248 extern void machine_restart_smp(char *);
 249 extern void machine_halt_smp(void);
 250 extern void machine_power_off_smp(void);
 251
 252 void (*_machine_restart)(char *command) = machine_restart_smp;
 253 void (*_machine_halt)(void) = machine_halt_smp;
 254 void (*_machine_power_off)(void) = machine_power_off_smp;
 255 #else
 256 /*
 257  * Reboot, halt and power_off routines for non SMP.
 258  */
 259 extern void reipl(unsigned long devno);
 260 static void do_machine_restart_nonsmp(char * __unused)
 261 {
 262         if (MACHINE_IS_VM)
 263                 cpcmd ("IPL", NULL, 0);
 264         else
 265                 reipl (0x10000 | S390_lowcore.ipl_device);
 266 }
 267
 268 static void do_machine_halt_nonsmp(void)
 269 {
 270         if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
 271                 cpcmd(vmhalt_cmd, NULL, 0);
 272         signal_processor(smp_processor_id(), sigp_stop_and_store_status);
 273 }
 274
 275 static void do_machine_power_off_nonsmp(void)
 276 {
 277         if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
 278                 cpcmd(vmpoff_cmd, NULL, 0);
 279         signal_processor(smp_processor_id(), sigp_stop_and_store_status);
 280 }
 281
 282 void (*_machine_restart)(char *command) = do_machine_restart_nonsmp;
 283 void (*_machine_halt)(void) = do_machine_halt_nonsmp;
 284 void (*_machine_power_off)(void) = do_machine_power_off_nonsmp;
 285 #endif
 286
 287  /*
 288  * Reboot, halt and power_off stubs. They just call _machine_restart,
 289  * _machine_halt or _machine_power_off.
 290  */
 291
 292 void machine_restart(char *command)
 293 {
 294         console_unblank();
 295         _machine_restart(command);
 296 }
 297
 298 EXPORT_SYMBOL(machine_restart);
 299
 300 void machine_halt(void)
 301 {
 302         console_unblank();
 303         _machine_halt();
 304 }
 305
 306 EXPORT_SYMBOL(machine_halt);
 307
 308 void machine_power_off(void)
 309 {
 310         console_unblank();
 311         _machine_power_off();
 312 }
 313
 314 EXPORT_SYMBOL(machine_power_off);
 315
 316 /*
 317  * Setup function called from init/main.c just after the banner
 318  * was printed.
 319  */
 320 extern char _pstart, _pend, _stext;
 321
 322 void __init setup_arch(char **cmdline_p)
 323 {
 324         unsigned long bootmap_size;
 325         unsigned long memory_start, memory_end;
 326         char c = ' ', cn, *to = command_line, *from = COMMAND_LINE;
 327         struct resource *res;
 328         unsigned long start_pfn, end_pfn;
 329         static unsigned int smptrap=0;
 330         unsigned long delay = 0;
 331         struct _lowcore *lc;
 332         int i;
 333
 334         if (smptrap)
 335                 return;
 336         smptrap=1;
 337
 338         /*
 339          * print what head.S has found out about the machine
 340          */
 341 #ifndef CONFIG_ARCH_S390X
 342         printk((MACHINE_IS_VM) ?
 343                "We are running under VM (31 bit mode)\n" :
 344                "We are running native (31 bit mode)\n");
 345         printk((MACHINE_HAS_IEEE) ?
 346                "This machine has an IEEE fpu\n" :
 347                "This machine has no IEEE fpu\n");
 348 #else /* CONFIG_ARCH_S390X */
 349         printk((MACHINE_IS_VM) ?
 350                "We are running under VM (64 bit mode)\n" :
 351                "We are running native (64 bit mode)\n");
 352 #endif /* CONFIG_ARCH_S390X */
 353
 354         ROOT_DEV = Root_RAM0;
 355         memory_start = (unsigned long) &_end;    /* fixit if use $CODELO etc*/
 356 #ifndef CONFIG_ARCH_S390X
 357         memory_end = memory_size & ~0x400000UL;  /* align memory end to 4MB */
 358         /*
 359          * We need some free virtual space to be able to do vmalloc.
 360          * On a machine with 2GB memory we make sure that we have at
 361          * least 128 MB free space for vmalloc.
 362          */
 363         if (memory_end > 1920*1024*1024)
 364                 memory_end = 1920*1024*1024;
 365 #else /* CONFIG_ARCH_S390X */
 366         memory_end = memory_size & ~0x200000UL;  /* detected in head.s */
 367 #endif /* CONFIG_ARCH_S390X */
 368         init_mm.start_code = PAGE_OFFSET;
 369         init_mm.end_code = (unsigned long) &_etext;
 370         init_mm.end_data = (unsigned long) &_edata;
 371         init_mm.brk = (unsigned long) &_end;
 372
 373         code_resource.start = (unsigned long) &_text;
 374         code_resource.end = (unsigned long) &_etext - 1;
 375         data_resource.start = (unsigned long) &_etext;
 376         data_resource.end = (unsigned long) &_edata - 1;
 377
 378         /* Save unparsed command line copy for /proc/cmdline */
 379         memcpy(saved_command_line, COMMAND_LINE, COMMAND_LINE_SIZE);
 380         saved_command_line[COMMAND_LINE_SIZE-1] = '\0';
 381
 382         for (;;) {
 383                 /*
 384                  * "mem=XXX[kKmM]" sets memsize
 385                  */
 386                 if (c == ' ' && strncmp(from, "mem=", 4) == 0) {
 387                         memory_end = simple_strtoul(from+4, &from, 0);
 388                         if ( *from == 'K' || *from == 'k' ) {
 389                                 memory_end = memory_end << 10;
 390                                 from++;
 391                         } else if ( *from == 'M' || *from == 'm' ) {
 392                                 memory_end = memory_end << 20;
 393                                 from++;
 394                         }
 395                 }
 396                 /*
 397                  * "ipldelay=XXX[sm]" sets ipl delay in seconds or minutes
 398                  */
 399                 if (c == ' ' && strncmp(from, "ipldelay=", 9) == 0) {
 400                         delay = simple_strtoul(from+9, &from, 0);
 401                         if (*from == 's' || *from == 'S') {
 402                                 delay = delay*1000000;
 403                                 from++;
 404                         } else if (*from == 'm' || *from == 'M') {
 405                                 delay = delay*60*1000000;
 406                                 from++;
 407                         }
 408                         /* now wait for the requested amount of time */
 409                         udelay(delay);
 410                 }
 411                 cn = *(from++);
 412                 if (!cn)
 413                         break;
 414                 if (cn == '\n')
 415                         cn = ' ';  /* replace newlines with space */
 416                 if (cn == 0x0d)
 417                         cn = ' ';  /* replace 0x0d with space */
 418                 if (cn == ' ' && c == ' ')
 419                         continue;  /* remove additional spaces */
 420                 c = cn;
 421                 if (to - command_line >= COMMAND_LINE_SIZE)
 422                         break;
 423                 *(to++) = c;
 424         }
 425         if (c == ' ' && to > command_line) to--;
 426         *to = '\0';
 427         *cmdline_p = command_line;
 428
 429         /*
 430          * partially used pages are not usable - thus
 431          * we are rounding upwards:
 432          */
 433         start_pfn = (__pa(&_end) + PAGE_SIZE - 1) >> PAGE_SHIFT;
 434         end_pfn = max_pfn = memory_end >> PAGE_SHIFT;
 435
 436         /*
 437          * Initialize the boot-time allocator (with low memory only):
 438          */
 439         bootmap_size = init_bootmem(start_pfn, end_pfn);
 440
 441         /*
 442          * Register RAM areas with the bootmem allocator.
 443          */
 444         for (i = 0; i < 16 && memory_chunk[i].size > 0; i++) {
 445                 unsigned long start_chunk, end_chunk;
 446
 447                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 448                         continue;
 449                 start_chunk = (memory_chunk[i].addr + PAGE_SIZE - 1);
 450                 start_chunk >>= PAGE_SHIFT;
 451                 end_chunk = (memory_chunk[i].addr + memory_chunk[i].size);
 452                 end_chunk >>= PAGE_SHIFT;
 453                 if (start_chunk < start_pfn)
 454                         start_chunk = start_pfn;
 455                 if (end_chunk > end_pfn)
 456                         end_chunk = end_pfn;
 457                 if (start_chunk < end_chunk)
 458                         free_bootmem(start_chunk << PAGE_SHIFT,
 459                                      (end_chunk - start_chunk) << PAGE_SHIFT);
 460         }
 461
 462         /*
 463          * Reserve the bootmem bitmap itself as well. We do this in two
 464          * steps (first step was init_bootmem()) because this catches
 465          * the (very unlikely) case of us accidentally initializing the
 466          * bootmem allocator with an invalid RAM area.
 467          */
 468         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size);
 469
 470 #ifdef CONFIG_BLK_DEV_INITRD
 471         if (INITRD_START) {
 472                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 473                         reserve_bootmem(INITRD_START, INITRD_SIZE);
 474                         initrd_start = INITRD_START;
 475                         initrd_end = initrd_start + INITRD_SIZE;
 476                 } else {
 477                         printk("initrd extends beyond end of memory "
 478                                "(0x%08lx > 0x%08lx)\ndisabling initrd\n",
 479                                initrd_start + INITRD_SIZE, memory_end);
 480                         initrd_start = initrd_end = 0;
 481                 }
 482         }
 483 #endif
 484
 485         /*
 486          * Setup lowcore for boot cpu
 487          */
 488 #ifndef CONFIG_ARCH_S390X
 489         lc = (struct _lowcore *) __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
 490         memset(lc, 0, PAGE_SIZE);
 491 #else /* CONFIG_ARCH_S390X */
 492         lc = (struct _lowcore *) __alloc_bootmem(2*PAGE_SIZE, 2*PAGE_SIZE, 0);
 493         memset(lc, 0, 2*PAGE_SIZE);
 494 #endif /* CONFIG_ARCH_S390X */
 495         lc->restart_psw.mask = PSW_BASE_BITS;
 496         lc->restart_psw.addr =
 497                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 498         lc->external_new_psw.mask = PSW_KERNEL_BITS;
 499         lc->external_new_psw.addr =
 500                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 501         lc->svc_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
 502         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 503         lc->program_new_psw.mask = PSW_KERNEL_BITS;
 504         lc->program_new_psw.addr =
 505                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 506         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 507         lc->mcck_new_psw.addr =
 508                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 509         lc->io_new_psw.mask = PSW_KERNEL_BITS;
 510         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 511         lc->ipl_device = S390_lowcore.ipl_device;
 512         lc->jiffy_timer = -1LL;
 513         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 514         lc->async_stack = (unsigned long)
 515                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 516         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 517         lc->thread_info = (unsigned long) &init_thread_union;
 518 #ifdef CONFIG_ARCH_S390X
 519         if (MACHINE_HAS_DIAG44)
 520                 lc->diag44_opcode = 0x83000044;
 521         else
 522                 lc->diag44_opcode = 0x07000700;
 523 #endif /* CONFIG_ARCH_S390X */
 524         set_prefix((u32)(unsigned long) lc);
 525         cpu_init();
 526         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
 527
 528         /*
 529          * Create kernel page tables and switch to virtual addressing.
 530          */
 531         paging_init();
 532
 533         res = alloc_bootmem_low(sizeof(struct resource));
 534         res->start = 0;
 535         res->end = memory_end;
 536         res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 537         request_resource(&iomem_resource, res);
 538         request_resource(res, &code_resource);
 539         request_resource(res, &data_resource);
 540
 541         /* Setup default console */
 542         conmode_default();
 543 }
 544
 545 void print_cpu_info(struct cpuinfo_S390 *cpuinfo)
 546 {
 547    printk("cpu %d "
 548 #ifdef CONFIG_SMP
 549            "phys_idx=%d "
 550 #endif
 551            "vers=%02X ident=%06X machine=%04X unused=%04X\n",
 552            cpuinfo->cpu_nr,
 553 #ifdef CONFIG_SMP
 554            cpuinfo->cpu_addr,
 555 #endif
 556            cpuinfo->cpu_id.version,
 557            cpuinfo->cpu_id.ident,
 558            cpuinfo->cpu_id.machine,
 559            cpuinfo->cpu_id.unused);
 560 }
 561
 562 /*
 563  * show_cpuinfo - Get information on one CPU for use by procfs.
 564  */
 565
 566 static int show_cpuinfo(struct seq_file *m, void *v)
 567 {
 568         struct cpuinfo_S390 *cpuinfo;
 569         unsigned long n = (unsigned long) v - 1;
 570
 571         if (!n) {
 572                 seq_printf(m, "vendor_id       : IBM/S390\n"
 573                                "# processors    : %i\n"
 574                                "bogomips per cpu: %lu.%02lu\n",
 575                                num_online_cpus(), loops_per_jiffy/(500000/HZ),
 576                                (loops_per_jiffy/(5000/HZ))%100);
 577         }
 578         if (cpu_online(n)) {
 579 #ifdef CONFIG_SMP
 580                 if (smp_processor_id() == n)
 581                         cpuinfo = &S390_lowcore.cpu_data;
 582                 else
 583                         cpuinfo = &lowcore_ptr[n]->cpu_data;
 584 #else
 585                 cpuinfo = &S390_lowcore.cpu_data;
 586 #endif
 587                 seq_printf(m, "processor %li: "
 588                                "version = %02X,  "
 589                                "identification = %06X,  "
 590                                "machine = %04X\n",
 591                                n, cpuinfo->cpu_id.version,
 592                                cpuinfo->cpu_id.ident,
 593                                cpuinfo->cpu_id.machine);
 594         }
 595         return 0;
 596 }
 597
 598 static void *c_start(struct seq_file *m, loff_t *pos)
 599 {
 600         return *pos < NR_CPUS ? (void *)((unsigned long) *pos + 1) : NULL;
 601 }
 602 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 603 {
 604         ++*pos;
 605         return c_start(m, pos);
 606 }
 607 static void c_stop(struct seq_file *m, void *v)
 608 {
 609 }
 610 struct seq_operations cpuinfo_op = {
 611         .start  = c_start,
 612         .next   = c_next,
 613         .stop   = c_stop,
 614         .show   = show_cpuinfo,
 615 };
 616
 617 /*
 618  * show_interrupts is needed by /proc/interrupts.
 619  */
 620
 621 static const char *intrclass_names[] = {
 622         "EXT",
 623         "I/O",
 624 };
 625
 626 int show_interrupts(struct seq_file *p, void *v)
 627 {
 628         int i = *(loff_t *) v, j;
 629
 630         if (i == 0) {
 631                 seq_puts(p, "           ");
 632                 for (j=0; j<NR_CPUS; j++)
 633                         if (cpu_online(j))
 634                                 seq_printf(p, "CPU%d       ",j);
 635                 seq_putc(p, '\n');
 636         }
 637
 638         if (i < NR_IRQS) {
 639                 seq_printf(p, "%s: ", intrclass_names[i]);
 640 #ifndef CONFIG_SMP
 641                 seq_printf(p, "%10u ", kstat_irqs(i));
 642 #else
 643                 for (j = 0; j < NR_CPUS; j++)
 644                         if (cpu_online(j))
 645                                 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 646 #endif
 647                 seq_putc(p, '\n');
 648
 649         }
 650
 651         return 0;
 652 }