arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) IBM Corp. 1999,2010
   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 #define KMSG_COMPONENT "setup"
  18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  19
  20 #include <linux/errno.h>
  21 #include <linux/module.h>
  22 #include <linux/sched.h>
  23 #include <linux/kernel.h>
  24 #include <linux/mm.h>
  25 #include <linux/stddef.h>
  26 #include <linux/unistd.h>
  27 #include <linux/ptrace.h>
  28 #include <linux/user.h>
  29 #include <linux/tty.h>
  30 #include <linux/ioport.h>
  31 #include <linux/delay.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/kernel_stat.h>
  38 #include <linux/device.h>
  39 #include <linux/notifier.h>
  40 #include <linux/pfn.h>
  41 #include <linux/ctype.h>
  42 #include <linux/reboot.h>
  43 #include <linux/topology.h>
  44 #include <linux/ftrace.h>
  45 #include <linux/kexec.h>
  46 #include <linux/crash_dump.h>
  47 #include <linux/memory.h>
  48
  49 #include <asm/ipl.h>
  50 #include <asm/uaccess.h>
  51 #include <asm/system.h>
  52 #include <asm/smp.h>
  53 #include <asm/mmu_context.h>
  54 #include <asm/cpcmd.h>
  55 #include <asm/lowcore.h>
  56 #include <asm/irq.h>
  57 #include <asm/page.h>
  58 #include <asm/ptrace.h>
  59 #include <asm/sections.h>
  60 #include <asm/ebcdic.h>
  61 #include <asm/compat.h>
  62 #include <asm/kvm_virtio.h>
  63 #include <asm/diag.h>
  64
  65 long psw_kernel_bits    = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
  66                            PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
  67 long psw_user_bits      = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
  68                            PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
  69                            PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
  70
  71 /*
  72  * User copy operations.
  73  */
  74 struct uaccess_ops uaccess;
  75 EXPORT_SYMBOL(uaccess);
  76
  77 /*
  78  * Machine setup..
  79  */
  80 unsigned int console_mode = 0;
  81 EXPORT_SYMBOL(console_mode);
  82
  83 unsigned int console_devno = -1;
  84 EXPORT_SYMBOL(console_devno);
  85
  86 unsigned int console_irq = -1;
  87 EXPORT_SYMBOL(console_irq);
  88
  89 unsigned long elf_hwcap = 0;
  90 char elf_platform[ELF_PLATFORM_SIZE];
  91
  92 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  93
  94 int __initdata memory_end_set;
  95 unsigned long __initdata memory_end;
  96
  97 /* An array with a pointer to the lowcore of every CPU. */
  98 struct _lowcore *lowcore_ptr[NR_CPUS];
  99 EXPORT_SYMBOL(lowcore_ptr);
 100
 101 /*
 102  * This is set up by the setup-routine at boot-time
 103  * for S390 need to find out, what we have to setup
 104  * using address 0x10400 ...
 105  */
 106
 107 #include <asm/setup.h>
 108
 109 /*
 110  * condev= and conmode= setup parameter.
 111  */
 112
 113 static int __init condev_setup(char *str)
 114 {
 115         int vdev;
 116
 117         vdev = simple_strtoul(str, &str, 0);
 118         if (vdev >= 0 && vdev < 65536) {
 119                 console_devno = vdev;
 120                 console_irq = -1;
 121         }
 122         return 1;
 123 }
 124
 125 __setup("condev=", condev_setup);
 126
 127 static void __init set_preferred_console(void)
 128 {
 129         if (MACHINE_IS_KVM)
 130                 add_preferred_console("hvc", 0, NULL);
 131         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 132                 add_preferred_console("ttyS", 0, NULL);
 133         else if (CONSOLE_IS_3270)
 134                 add_preferred_console("tty3270", 0, NULL);
 135 }
 136
 137 static int __init conmode_setup(char *str)
 138 {
 139 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 140         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 141                 SET_CONSOLE_SCLP;
 142 #endif
 143 #if defined(CONFIG_TN3215_CONSOLE)
 144         if (strncmp(str, "3215", 5) == 0)
 145                 SET_CONSOLE_3215;
 146 #endif
 147 #if defined(CONFIG_TN3270_CONSOLE)
 148         if (strncmp(str, "3270", 5) == 0)
 149                 SET_CONSOLE_3270;
 150 #endif
 151         set_preferred_console();
 152         return 1;
 153 }
 154
 155 __setup("conmode=", conmode_setup);
 156
 157 static void __init conmode_default(void)
 158 {
 159         char query_buffer[1024];
 160         char *ptr;
 161
 162         if (MACHINE_IS_VM) {
 163                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 164                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 165                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 166                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 167                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 168                 ptr = strstr(query_buffer, "CONMODE");
 169                 /*
 170                  * Set the conmode to 3215 so that the device recognition
 171                  * will set the cu_type of the console to 3215. If the
 172                  * conmode is 3270 and we don't set it back then both
 173                  * 3215 and the 3270 driver will try to access the console
 174                  * device (3215 as console and 3270 as normal tty).
 175                  */
 176                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 177                 if (ptr == NULL) {
 178 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 179                         SET_CONSOLE_SCLP;
 180 #endif
 181                         return;
 182                 }
 183                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 184 #if defined(CONFIG_TN3270_CONSOLE)
 185                         SET_CONSOLE_3270;
 186 #elif defined(CONFIG_TN3215_CONSOLE)
 187                         SET_CONSOLE_3215;
 188 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 189                         SET_CONSOLE_SCLP;
 190 #endif
 191                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 192 #if defined(CONFIG_TN3215_CONSOLE)
 193                         SET_CONSOLE_3215;
 194 #elif defined(CONFIG_TN3270_CONSOLE)
 195                         SET_CONSOLE_3270;
 196 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 197                         SET_CONSOLE_SCLP;
 198 #endif
 199                 }
 200         } else {
 201 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 202                 SET_CONSOLE_SCLP;
 203 #endif
 204         }
 205 }
 206
 207 #ifdef CONFIG_ZFCPDUMP
 208 static void __init setup_zfcpdump(unsigned int console_devno)
 209 {
 210         static char str[41];
 211
 212         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 213                 return;
 214         if (console_devno != -1)
 215                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 216                         ipl_info.data.fcp.dev_id.devno, console_devno);
 217         else
 218                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 219                         ipl_info.data.fcp.dev_id.devno);
 220         strcat(boot_command_line, str);
 221         console_loglevel = 2;
 222 }
 223 #else
 224 static inline void setup_zfcpdump(unsigned int console_devno) {}
 225 #endif /* CONFIG_ZFCPDUMP */
 226
 227  /*
 228  * Reboot, halt and power_off stubs. They just call _machine_restart,
 229  * _machine_halt or _machine_power_off.
 230  */
 231
 232 void machine_restart(char *command)
 233 {
 234         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 235                 /*
 236                  * Only unblank the console if we are called in enabled
 237                  * context or a bust_spinlocks cleared the way for us.
 238                  */
 239                 console_unblank();
 240         _machine_restart(command);
 241 }
 242
 243 void machine_halt(void)
 244 {
 245         if (!in_interrupt() || oops_in_progress)
 246                 /*
 247                  * Only unblank the console if we are called in enabled
 248                  * context or a bust_spinlocks cleared the way for us.
 249                  */
 250                 console_unblank();
 251         _machine_halt();
 252 }
 253
 254 void machine_power_off(void)
 255 {
 256         if (!in_interrupt() || oops_in_progress)
 257                 /*
 258                  * Only unblank the console if we are called in enabled
 259                  * context or a bust_spinlocks cleared the way for us.
 260                  */
 261                 console_unblank();
 262         _machine_power_off();
 263 }
 264
 265 /*
 266  * Dummy power off function.
 267  */
 268 void (*pm_power_off)(void) = machine_power_off;
 269
 270 static int __init early_parse_mem(char *p)
 271 {
 272         memory_end = memparse(p, &p);
 273         memory_end_set = 1;
 274         return 0;
 275 }
 276 early_param("mem", early_parse_mem);
 277
 278 unsigned int user_mode = HOME_SPACE_MODE;
 279 EXPORT_SYMBOL_GPL(user_mode);
 280
 281 static int set_amode_and_uaccess(unsigned long user_amode,
 282                                  unsigned long user32_amode)
 283 {
 284         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 285                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 286                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 287 #ifdef CONFIG_COMPAT
 288         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 289                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 290                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 291         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 292                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 293                           PSW32_MASK_PSTATE;
 294 #endif
 295         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 296                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 297
 298         if (MACHINE_HAS_MVCOS) {
 299                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 300                 return 1;
 301         } else {
 302                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 303                 return 0;
 304         }
 305 }
 306
 307 /*
 308  * Switch kernel/user addressing modes?
 309  */
 310 static int __init early_parse_switch_amode(char *p)
 311 {
 312         user_mode = PRIMARY_SPACE_MODE;
 313         return 0;
 314 }
 315 early_param("switch_amode", early_parse_switch_amode);
 316
 317 static int __init early_parse_user_mode(char *p)
 318 {
 319         if (p && strcmp(p, "primary") == 0)
 320                 user_mode = PRIMARY_SPACE_MODE;
 321         else if (!p || strcmp(p, "home") == 0)
 322                 user_mode = HOME_SPACE_MODE;
 323         else
 324                 return 1;
 325         return 0;
 326 }
 327 early_param("user_mode", early_parse_user_mode);
 328
 329 static void setup_addressing_mode(void)
 330 {
 331         if (user_mode == PRIMARY_SPACE_MODE) {
 332                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 333                         pr_info("Address spaces switched, "
 334                                 "mvcos available\n");
 335                 else
 336                         pr_info("Address spaces switched, "
 337                                 "mvcos not available\n");
 338         }
 339 }
 340
 341 static void __init
 342 setup_lowcore(void)
 343 {
 344         struct _lowcore *lc;
 345
 346         /*
 347          * Setup lowcore for boot cpu
 348          */
 349         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 350         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 351         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 352         lc->restart_psw.addr =
 353                 PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 354         if (user_mode != HOME_SPACE_MODE)
 355                 lc->restart_psw.mask |= PSW_ASC_HOME;
 356         lc->external_new_psw.mask = psw_kernel_bits;
 357         lc->external_new_psw.addr =
 358                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 359         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 360         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 361         lc->program_new_psw.mask = psw_kernel_bits;
 362         lc->program_new_psw.addr =
 363                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 364         lc->mcck_new_psw.mask =
 365                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 366         lc->mcck_new_psw.addr =
 367                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 368         lc->io_new_psw.mask = psw_kernel_bits;
 369         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 370         lc->clock_comparator = -1ULL;
 371         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 372         lc->async_stack = (unsigned long)
 373                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 374         lc->panic_stack = (unsigned long)
 375                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 376         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 377         lc->thread_info = (unsigned long) &init_thread_union;
 378         lc->machine_flags = S390_lowcore.machine_flags;
 379         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 380         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 381                MAX_FACILITY_BIT/8);
 382 #ifndef CONFIG_64BIT
 383         if (MACHINE_HAS_IEEE) {
 384                 lc->extended_save_area_addr = (__u32)
 385                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 386                 /* enable extended save area */
 387                 __ctl_set_bit(14, 29);
 388         }
 389 #else
 390         lc->cmf_hpp = -1ULL;
 391         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 392 #endif
 393         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 394         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 395         lc->exit_timer = S390_lowcore.exit_timer;
 396         lc->user_timer = S390_lowcore.user_timer;
 397         lc->system_timer = S390_lowcore.system_timer;
 398         lc->steal_timer = S390_lowcore.steal_timer;
 399         lc->last_update_timer = S390_lowcore.last_update_timer;
 400         lc->last_update_clock = S390_lowcore.last_update_clock;
 401         lc->ftrace_func = S390_lowcore.ftrace_func;
 402         set_prefix((u32)(unsigned long) lc);
 403         lowcore_ptr[0] = lc;
 404 }
 405
 406 static struct resource code_resource = {
 407         .name  = "Kernel code",
 408         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 409 };
 410
 411 static struct resource data_resource = {
 412         .name = "Kernel data",
 413         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 414 };
 415
 416 static struct resource bss_resource = {
 417         .name = "Kernel bss",
 418         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 419 };
 420
 421 static struct resource __initdata *standard_resources[] = {
 422         &code_resource,
 423         &data_resource,
 424         &bss_resource,
 425 };
 426
 427 static void __init setup_resources(void)
 428 {
 429         struct resource *res, *std_res, *sub_res;
 430         int i, j;
 431
 432         code_resource.start = (unsigned long) &_text;
 433         code_resource.end = (unsigned long) &_etext - 1;
 434         data_resource.start = (unsigned long) &_etext;
 435         data_resource.end = (unsigned long) &_edata - 1;
 436         bss_resource.start = (unsigned long) &__bss_start;
 437         bss_resource.end = (unsigned long) &__bss_stop - 1;
 438
 439         for (i = 0; i < MEMORY_CHUNKS; i++) {
 440                 if (!memory_chunk[i].size)
 441                         continue;
 442                 if (memory_chunk[i].type == CHUNK_OLDMEM ||
 443                     memory_chunk[i].type == CHUNK_CRASHK)
 444                         continue;
 445                 res = alloc_bootmem_low(sizeof(*res));
 446                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 447                 switch (memory_chunk[i].type) {
 448                 case CHUNK_READ_WRITE:
 449                         res->name = "System RAM";
 450                         break;
 451                 case CHUNK_READ_ONLY:
 452                         res->name = "System ROM";
 453                         res->flags |= IORESOURCE_READONLY;
 454                         break;
 455                 default:
 456                         res->name = "reserved";
 457                 }
 458                 res->start = memory_chunk[i].addr;
 459                 res->end = res->start + memory_chunk[i].size - 1;
 460                 request_resource(&iomem_resource, res);
 461
 462                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 463                         std_res = standard_resources[j];
 464                         if (std_res->start < res->start ||
 465                             std_res->start > res->end)
 466                                 continue;
 467                         if (std_res->end > res->end) {
 468                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 469                                 *sub_res = *std_res;
 470                                 sub_res->end = res->end;
 471                                 std_res->start = res->end + 1;
 472                                 request_resource(res, sub_res);
 473                         } else {
 474                                 request_resource(res, std_res);
 475                         }
 476                 }
 477         }
 478 }
 479
 480 unsigned long real_memory_size;
 481 EXPORT_SYMBOL_GPL(real_memory_size);
 482
 483 static void __init setup_memory_end(void)
 484 {
 485         unsigned long memory_size;
 486         unsigned long max_mem;
 487         int i;
 488
 489
 490 #ifdef CONFIG_ZFCPDUMP
 491         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
 492                 memory_end = ZFCPDUMP_HSA_SIZE;
 493                 memory_end_set = 1;
 494         }
 495 #endif
 496         memory_size = 0;
 497         memory_end &= PAGE_MASK;
 498
 499         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 500         memory_end = min(max_mem, memory_end);
 501
 502         /*
 503          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 504          * extra checks that HOLES_IN_ZONE would require.
 505          */
 506         for (i = 0; i < MEMORY_CHUNKS; i++) {
 507                 unsigned long start, end;
 508                 struct mem_chunk *chunk;
 509                 unsigned long align;
 510
 511                 chunk = &memory_chunk[i];
 512                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 513                 start = (chunk->addr + align - 1) & ~(align - 1);
 514                 end = (chunk->addr + chunk->size) & ~(align - 1);
 515                 if (start >= end)
 516                         memset(chunk, 0, sizeof(*chunk));
 517                 else {
 518                         chunk->addr = start;
 519                         chunk->size = end - start;
 520                 }
 521         }
 522
 523         for (i = 0; i < MEMORY_CHUNKS; i++) {
 524                 struct mem_chunk *chunk = &memory_chunk[i];
 525
 526                 real_memory_size = max(real_memory_size,
 527                                        chunk->addr + chunk->size);
 528                 if (chunk->addr >= max_mem) {
 529                         memset(chunk, 0, sizeof(*chunk));
 530                         continue;
 531                 }
 532                 if (chunk->addr + chunk->size > max_mem)
 533                         chunk->size = max_mem - chunk->addr;
 534                 memory_size = max(memory_size, chunk->addr + chunk->size);
 535         }
 536         if (!memory_end)
 537                 memory_end = memory_size;
 538 }
 539
 540 void *restart_stack __attribute__((__section__(".data")));
 541
 542 /*
 543  * Setup new PSW and allocate stack for PSW restart interrupt
 544  */
 545 static void __init setup_restart_psw(void)
 546 {
 547         psw_t psw;
 548
 549         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
 550         restart_stack += ASYNC_SIZE;
 551
 552         /*
 553          * Setup restart PSW for absolute zero lowcore. This is necesary
 554          * if PSW restart is done on an offline CPU that has lowcore zero
 555          */
 556         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 557         psw.addr = PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 558         copy_to_absolute_zero(&S390_lowcore.restart_psw, &psw, sizeof(psw));
 559 }
 560
 561 #ifdef CONFIG_CRASH_DUMP
 562
 563 /*
 564  * Find suitable location for crashkernel memory
 565  */
 566 static unsigned long __init find_crash_base(unsigned long crash_size,
 567                                             char **msg)
 568 {
 569         unsigned long crash_base;
 570         struct mem_chunk *chunk;
 571         int i;
 572
 573         if (memory_chunk[0].size < crash_size) {
 574                 *msg = "first memory chunk must be at least crashkernel size";
 575                 return 0;
 576         }
 577         if (is_kdump_kernel() && (crash_size == OLDMEM_SIZE))
 578                 return OLDMEM_BASE;
 579
 580         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
 581                 chunk = &memory_chunk[i];
 582                 if (chunk->size == 0)
 583                         continue;
 584                 if (chunk->type != CHUNK_READ_WRITE)
 585                         continue;
 586                 if (chunk->size < crash_size)
 587                         continue;
 588                 crash_base = (chunk->addr + chunk->size) - crash_size;
 589                 if (crash_base < crash_size)
 590                         continue;
 591                 if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
 592                         continue;
 593                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 594                         continue;
 595                 return crash_base;
 596         }
 597         *msg = "no suitable area found";
 598         return 0;
 599 }
 600
 601 /*
 602  * Check if crash_base and crash_size is valid
 603  */
 604 static int __init verify_crash_base(unsigned long crash_base,
 605                                     unsigned long crash_size,
 606                                     char **msg)
 607 {
 608         struct mem_chunk *chunk;
 609         int i;
 610
 611         /*
 612          * Because we do the swap to zero, we must have at least 'crash_size'
 613          * bytes free space before crash_base
 614          */
 615         if (crash_size > crash_base) {
 616                 *msg = "crashkernel offset must be greater than size";
 617                 return -EINVAL;
 618         }
 619
 620         /* First memory chunk must be at least crash_size */
 621         if (memory_chunk[0].size < crash_size) {
 622                 *msg = "first memory chunk must be at least crashkernel size";
 623                 return -EINVAL;
 624         }
 625         /* Check if we fit into the respective memory chunk */
 626         for (i = 0; i < MEMORY_CHUNKS; i++) {
 627                 chunk = &memory_chunk[i];
 628                 if (chunk->size == 0)
 629                         continue;
 630                 if (crash_base < chunk->addr)
 631                         continue;
 632                 if (crash_base >= chunk->addr + chunk->size)
 633                         continue;
 634                 /* we have found the memory chunk */
 635                 if (crash_base + crash_size > chunk->addr + chunk->size) {
 636                         *msg = "selected memory chunk is too small for "
 637                                 "crashkernel memory";
 638                         return -EINVAL;
 639                 }
 640                 return 0;
 641         }
 642         *msg = "invalid memory range specified";
 643         return -EINVAL;
 644 }
 645
 646 /*
 647  * Reserve kdump memory by creating a memory hole in the mem_chunk array
 648  */
 649 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
 650                                          int type)
 651 {
 652
 653         create_mem_hole(memory_chunk, addr, size, type);
 654 }
 655
 656 /*
 657  * When kdump is enabled, we have to ensure that no memory from
 658  * the area [0 - crashkernel memory size] and
 659  * [crashk_res.start - crashk_res.end] is set offline.
 660  */
 661 static int kdump_mem_notifier(struct notifier_block *nb,
 662                               unsigned long action, void *data)
 663 {
 664         struct memory_notify *arg = data;
 665
 666         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 667                 return NOTIFY_BAD;
 668         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 669                 return NOTIFY_OK;
 670         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 671                 return NOTIFY_OK;
 672         return NOTIFY_BAD;
 673 }
 674
 675 static struct notifier_block kdump_mem_nb = {
 676         .notifier_call = kdump_mem_notifier,
 677 };
 678
 679 #endif
 680
 681 /*
 682  * Make sure that oldmem, where the dump is stored, is protected
 683  */
 684 static void reserve_oldmem(void)
 685 {
 686 #ifdef CONFIG_CRASH_DUMP
 687         if (!OLDMEM_BASE)
 688                 return;
 689
 690         reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
 691         reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
 692                               CHUNK_OLDMEM);
 693         if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
 694                 saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
 695         else
 696                 saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
 697 #endif
 698 }
 699
 700 /*
 701  * Reserve memory for kdump kernel to be loaded with kexec
 702  */
 703 static void __init reserve_crashkernel(void)
 704 {
 705 #ifdef CONFIG_CRASH_DUMP
 706         unsigned long long crash_base, crash_size;
 707         char *msg;
 708         int rc;
 709
 710         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 711                                &crash_base);
 712         if (rc || crash_size == 0)
 713                 return;
 714         crash_base = PAGE_ALIGN(crash_base);
 715         crash_size = PAGE_ALIGN(crash_size);
 716         if (register_memory_notifier(&kdump_mem_nb))
 717                 return;
 718         if (!crash_base)
 719                 crash_base = find_crash_base(crash_size, &msg);
 720         if (!crash_base) {
 721                 pr_info("crashkernel reservation failed: %s\n", msg);
 722                 unregister_memory_notifier(&kdump_mem_nb);
 723                 return;
 724         }
 725         if (verify_crash_base(crash_base, crash_size, &msg)) {
 726                 pr_info("crashkernel reservation failed: %s\n", msg);
 727                 unregister_memory_notifier(&kdump_mem_nb);
 728                 return;
 729         }
 730         if (!OLDMEM_BASE && MACHINE_IS_VM)
 731                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 732         crashk_res.start = crash_base;
 733         crashk_res.end = crash_base + crash_size - 1;
 734         insert_resource(&iomem_resource, &crashk_res);
 735         reserve_kdump_bootmem(crash_base, crash_size, CHUNK_READ_WRITE);
 736         pr_info("Reserving %lluMB of memory at %lluMB "
 737                 "for crashkernel (System RAM: %luMB)\n",
 738                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
 739 #endif
 740 }
 741
 742 static void __init
 743 setup_memory(void)
 744 {
 745         unsigned long bootmap_size;
 746         unsigned long start_pfn, end_pfn;
 747         int i;
 748
 749         /*
 750          * partially used pages are not usable - thus
 751          * we are rounding upwards:
 752          */
 753         start_pfn = PFN_UP(__pa(&_end));
 754         end_pfn = max_pfn = PFN_DOWN(memory_end);
 755
 756 #ifdef CONFIG_BLK_DEV_INITRD
 757         /*
 758          * Move the initrd in case the bitmap of the bootmem allocater
 759          * would overwrite it.
 760          */
 761
 762         if (INITRD_START && INITRD_SIZE) {
 763                 unsigned long bmap_size;
 764                 unsigned long start;
 765
 766                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 767                 bmap_size = PFN_PHYS(bmap_size);
 768
 769                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 770                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 771
 772 #ifdef CONFIG_CRASH_DUMP
 773                         if (OLDMEM_BASE) {
 774                                 /* Move initrd behind kdump oldmem */
 775                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
 776                                     start < OLDMEM_BASE + OLDMEM_SIZE)
 777                                         start = OLDMEM_BASE + OLDMEM_SIZE;
 778                         }
 779 #endif
 780                         if (start + INITRD_SIZE > memory_end) {
 781                                 pr_err("initrd extends beyond end of "
 782                                        "memory (0x%08lx > 0x%08lx) "
 783                                        "disabling initrd\n",
 784                                        start + INITRD_SIZE, memory_end);
 785                                 INITRD_START = INITRD_SIZE = 0;
 786                         } else {
 787                                 pr_info("Moving initrd (0x%08lx -> "
 788                                         "0x%08lx, size: %ld)\n",
 789                                         INITRD_START, start, INITRD_SIZE);
 790                                 memmove((void *) start, (void *) INITRD_START,
 791                                         INITRD_SIZE);
 792                                 INITRD_START = start;
 793                         }
 794                 }
 795         }
 796 #endif
 797
 798         /*
 799          * Initialize the boot-time allocator
 800          */
 801         bootmap_size = init_bootmem(start_pfn, end_pfn);
 802
 803         /*
 804          * Register RAM areas with the bootmem allocator.
 805          */
 806
 807         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 808                 unsigned long start_chunk, end_chunk, pfn;
 809
 810                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 811                         continue;
 812                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 813                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 814                 end_chunk = min(end_chunk, end_pfn);
 815                 if (start_chunk >= end_chunk)
 816                         continue;
 817                 add_active_range(0, start_chunk, end_chunk);
 818                 pfn = max(start_chunk, start_pfn);
 819                 for (; pfn < end_chunk; pfn++)
 820                         page_set_storage_key(PFN_PHYS(pfn),
 821                                              PAGE_DEFAULT_KEY, 0);
 822         }
 823
 824         psw_set_key(PAGE_DEFAULT_KEY);
 825
 826         free_bootmem_with_active_regions(0, max_pfn);
 827
 828         /*
 829          * Reserve memory used for lowcore/command line/kernel image.
 830          */
 831         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 832         reserve_bootmem((unsigned long)_stext,
 833                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 834                         BOOTMEM_DEFAULT);
 835         /*
 836          * Reserve the bootmem bitmap itself as well. We do this in two
 837          * steps (first step was init_bootmem()) because this catches
 838          * the (very unlikely) case of us accidentally initializing the
 839          * bootmem allocator with an invalid RAM area.
 840          */
 841         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 842                         BOOTMEM_DEFAULT);
 843
 844 #ifdef CONFIG_CRASH_DUMP
 845         if (crashk_res.start)
 846                 reserve_bootmem(crashk_res.start,
 847                                 crashk_res.end - crashk_res.start + 1,
 848                                 BOOTMEM_DEFAULT);
 849         if (is_kdump_kernel())
 850                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
 851                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
 852 #endif
 853 #ifdef CONFIG_BLK_DEV_INITRD
 854         if (INITRD_START && INITRD_SIZE) {
 855                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 856                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 857                                         BOOTMEM_DEFAULT);
 858                         initrd_start = INITRD_START;
 859                         initrd_end = initrd_start + INITRD_SIZE;
 860                 } else {
 861                         pr_err("initrd extends beyond end of "
 862                                "memory (0x%08lx > 0x%08lx) "
 863                                "disabling initrd\n",
 864                                initrd_start + INITRD_SIZE, memory_end);
 865                         initrd_start = initrd_end = 0;
 866                 }
 867         }
 868 #endif
 869 }
 870
 871 /*
 872  * Setup hardware capabilities.
 873  */
 874 static void __init setup_hwcaps(void)
 875 {
 876         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 877         struct cpuid cpu_id;
 878         int i;
 879
 880         /*
 881          * The store facility list bits numbers as found in the principles
 882          * of operation are numbered with bit 1UL<<31 as number 0 to
 883          * bit 1UL<<0 as number 31.
 884          *   Bit 0: instructions named N3, "backported" to esa-mode
 885          *   Bit 2: z/Architecture mode is active
 886          *   Bit 7: the store-facility-list-extended facility is installed
 887          *   Bit 17: the message-security assist is installed
 888          *   Bit 19: the long-displacement facility is installed
 889          *   Bit 21: the extended-immediate facility is installed
 890          *   Bit 22: extended-translation facility 3 is installed
 891          *   Bit 30: extended-translation facility 3 enhancement facility
 892          * These get translated to:
 893          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 894          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 895          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 896          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 897          */
 898         for (i = 0; i < 6; i++)
 899                 if (test_facility(stfl_bits[i]))
 900                         elf_hwcap |= 1UL << i;
 901
 902         if (test_facility(22) && test_facility(30))
 903                 elf_hwcap |= HWCAP_S390_ETF3EH;
 904
 905         /*
 906          * Check for additional facilities with store-facility-list-extended.
 907          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 908          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 909          * as stored by stfl, bits 32-xxx contain additional facilities.
 910          * How many facility words are stored depends on the number of
 911          * doublewords passed to the instruction. The additional facilities
 912          * are:
 913          *   Bit 42: decimal floating point facility is installed
 914          *   Bit 44: perform floating point operation facility is installed
 915          * translated to:
 916          *   HWCAP_S390_DFP bit 6 (42 && 44).
 917          */
 918         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 919                 elf_hwcap |= HWCAP_S390_DFP;
 920
 921         /*
 922          * Huge page support HWCAP_S390_HPAGE is bit 7.
 923          */
 924         if (MACHINE_HAS_HPAGE)
 925                 elf_hwcap |= HWCAP_S390_HPAGE;
 926
 927         /*
 928          * 64-bit register support for 31-bit processes
 929          * HWCAP_S390_HIGH_GPRS is bit 9.
 930          */
 931         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 932
 933         get_cpu_id(&cpu_id);
 934         switch (cpu_id.machine) {
 935         case 0x9672:
 936 #if !defined(CONFIG_64BIT)
 937         default:        /* Use "g5" as default for 31 bit kernels. */
 938 #endif
 939                 strcpy(elf_platform, "g5");
 940                 break;
 941         case 0x2064:
 942         case 0x2066:
 943 #if defined(CONFIG_64BIT)
 944         default:        /* Use "z900" as default for 64 bit kernels. */
 945 #endif
 946                 strcpy(elf_platform, "z900");
 947                 break;
 948         case 0x2084:
 949         case 0x2086:
 950                 strcpy(elf_platform, "z990");
 951                 break;
 952         case 0x2094:
 953         case 0x2096:
 954                 strcpy(elf_platform, "z9-109");
 955                 break;
 956         case 0x2097:
 957         case 0x2098:
 958                 strcpy(elf_platform, "z10");
 959                 break;
 960         case 0x2817:
 961         case 0x2818:
 962                 strcpy(elf_platform, "z196");
 963                 break;
 964         }
 965 }
 966
 967 /*
 968  * Setup function called from init/main.c just after the banner
 969  * was printed.
 970  */
 971
 972 void __init
 973 setup_arch(char **cmdline_p)
 974 {
 975         /*
 976          * print what head.S has found out about the machine
 977          */
 978 #ifndef CONFIG_64BIT
 979         if (MACHINE_IS_VM)
 980                 pr_info("Linux is running as a z/VM "
 981                         "guest operating system in 31-bit mode\n");
 982         else if (MACHINE_IS_LPAR)
 983                 pr_info("Linux is running natively in 31-bit mode\n");
 984         if (MACHINE_HAS_IEEE)
 985                 pr_info("The hardware system has IEEE compatible "
 986                         "floating point units\n");
 987         else
 988                 pr_info("The hardware system has no IEEE compatible "
 989                         "floating point units\n");
 990 #else /* CONFIG_64BIT */
 991         if (MACHINE_IS_VM)
 992                 pr_info("Linux is running as a z/VM "
 993                         "guest operating system in 64-bit mode\n");
 994         else if (MACHINE_IS_KVM)
 995                 pr_info("Linux is running under KVM in 64-bit mode\n");
 996         else if (MACHINE_IS_LPAR)
 997                 pr_info("Linux is running natively in 64-bit mode\n");
 998 #endif /* CONFIG_64BIT */
 999
1000         /* Have one command line that is parsed and saved in /proc/cmdline */
1001         /* boot_command_line has been already set up in early.c */
1002         *cmdline_p = boot_command_line;
1003
1004         ROOT_DEV = Root_RAM0;
1005
1006         init_mm.start_code = PAGE_OFFSET;
1007         init_mm.end_code = (unsigned long) &_etext;
1008         init_mm.end_data = (unsigned long) &_edata;
1009         init_mm.brk = (unsigned long) &_end;
1010
1011         if (MACHINE_HAS_MVCOS)
1012                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1013         else
1014                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1015
1016         parse_early_param();
1017
1018         setup_ipl();
1019         setup_memory_end();
1020         setup_addressing_mode();
1021         reserve_oldmem();
1022         reserve_crashkernel();
1023         setup_memory();
1024         setup_resources();
1025         setup_restart_psw();
1026         setup_lowcore();
1027
1028         cpu_init();
1029         s390_init_cpu_topology();
1030
1031         /*
1032          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1033          */
1034         setup_hwcaps();
1035
1036         /*
1037          * Create kernel page tables and switch to virtual addressing.
1038          */
1039         paging_init();
1040
1041         /* Setup default console */
1042         conmode_default();
1043         set_preferred_console();
1044
1045         /* Setup zfcpdump support */
1046         setup_zfcpdump(console_devno);
1047 }