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_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
  66                           PSW_MASK_EA | PSW_MASK_BA;
  67 long psw_user_bits      = PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
  68                           PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
  69                           PSW_MASK_PSTATE | PSW_ASC_HOME;
  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 (OLDMEM_BASE)
 215                 return;
 216         if (console_devno != -1)
 217                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 218                         ipl_info.data.fcp.dev_id.devno, console_devno);
 219         else
 220                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 221                         ipl_info.data.fcp.dev_id.devno);
 222         strcat(boot_command_line, str);
 223         console_loglevel = 2;
 224 }
 225 #else
 226 static inline void setup_zfcpdump(unsigned int console_devno) {}
 227 #endif /* CONFIG_ZFCPDUMP */
 228
 229  /*
 230  * Reboot, halt and power_off stubs. They just call _machine_restart,
 231  * _machine_halt or _machine_power_off.
 232  */
 233
 234 void machine_restart(char *command)
 235 {
 236         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 237                 /*
 238                  * Only unblank the console if we are called in enabled
 239                  * context or a bust_spinlocks cleared the way for us.
 240                  */
 241                 console_unblank();
 242         _machine_restart(command);
 243 }
 244
 245 void machine_halt(void)
 246 {
 247         if (!in_interrupt() || oops_in_progress)
 248                 /*
 249                  * Only unblank the console if we are called in enabled
 250                  * context or a bust_spinlocks cleared the way for us.
 251                  */
 252                 console_unblank();
 253         _machine_halt();
 254 }
 255
 256 void machine_power_off(void)
 257 {
 258         if (!in_interrupt() || oops_in_progress)
 259                 /*
 260                  * Only unblank the console if we are called in enabled
 261                  * context or a bust_spinlocks cleared the way for us.
 262                  */
 263                 console_unblank();
 264         _machine_power_off();
 265 }
 266
 267 /*
 268  * Dummy power off function.
 269  */
 270 void (*pm_power_off)(void) = machine_power_off;
 271
 272 static int __init early_parse_mem(char *p)
 273 {
 274         memory_end = memparse(p, &p);
 275         memory_end_set = 1;
 276         return 0;
 277 }
 278 early_param("mem", early_parse_mem);
 279
 280 unsigned int user_mode = HOME_SPACE_MODE;
 281 EXPORT_SYMBOL_GPL(user_mode);
 282
 283 static int set_amode_primary(void)
 284 {
 285         psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
 286         psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
 287 #ifdef CONFIG_COMPAT
 288         psw32_user_bits =
 289                 (psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
 290 #endif
 291
 292         if (MACHINE_HAS_MVCOS) {
 293                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 294                 return 1;
 295         } else {
 296                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 297                 return 0;
 298         }
 299 }
 300
 301 /*
 302  * Switch kernel/user addressing modes?
 303  */
 304 static int __init early_parse_switch_amode(char *p)
 305 {
 306         user_mode = PRIMARY_SPACE_MODE;
 307         return 0;
 308 }
 309 early_param("switch_amode", early_parse_switch_amode);
 310
 311 static int __init early_parse_user_mode(char *p)
 312 {
 313         if (p && strcmp(p, "primary") == 0)
 314                 user_mode = PRIMARY_SPACE_MODE;
 315         else if (!p || strcmp(p, "home") == 0)
 316                 user_mode = HOME_SPACE_MODE;
 317         else
 318                 return 1;
 319         return 0;
 320 }
 321 early_param("user_mode", early_parse_user_mode);
 322
 323 static void setup_addressing_mode(void)
 324 {
 325         if (user_mode == PRIMARY_SPACE_MODE) {
 326                 if (set_amode_primary())
 327                         pr_info("Address spaces switched, "
 328                                 "mvcos available\n");
 329                 else
 330                         pr_info("Address spaces switched, "
 331                                 "mvcos not available\n");
 332         }
 333 }
 334
 335 static void __init
 336 setup_lowcore(void)
 337 {
 338         struct _lowcore *lc;
 339
 340         /*
 341          * Setup lowcore for boot cpu
 342          */
 343         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 344         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 345         lc->restart_psw.mask = psw_kernel_bits;
 346         lc->restart_psw.addr =
 347                 PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 348         lc->external_new_psw.mask = psw_kernel_bits |
 349                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 350         lc->external_new_psw.addr =
 351                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 352         lc->svc_new_psw.mask = psw_kernel_bits |
 353                 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 354         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 355         lc->program_new_psw.mask = psw_kernel_bits |
 356                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 357         lc->program_new_psw.addr =
 358                 PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
 359         lc->mcck_new_psw.mask = psw_kernel_bits;
 360         lc->mcck_new_psw.addr =
 361                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 362         lc->io_new_psw.mask = psw_kernel_bits |
 363                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 364         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 365         lc->clock_comparator = -1ULL;
 366         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 367         lc->async_stack = (unsigned long)
 368                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 369         lc->panic_stack = (unsigned long)
 370                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 371         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 372         lc->thread_info = (unsigned long) &init_thread_union;
 373         lc->machine_flags = S390_lowcore.machine_flags;
 374         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 375         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 376                MAX_FACILITY_BIT/8);
 377 #ifndef CONFIG_64BIT
 378         if (MACHINE_HAS_IEEE) {
 379                 lc->extended_save_area_addr = (__u32)
 380                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 381                 /* enable extended save area */
 382                 __ctl_set_bit(14, 29);
 383         }
 384 #else
 385         lc->cmf_hpp = -1ULL;
 386         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 387 #endif
 388         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 389         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 390         lc->exit_timer = S390_lowcore.exit_timer;
 391         lc->user_timer = S390_lowcore.user_timer;
 392         lc->system_timer = S390_lowcore.system_timer;
 393         lc->steal_timer = S390_lowcore.steal_timer;
 394         lc->last_update_timer = S390_lowcore.last_update_timer;
 395         lc->last_update_clock = S390_lowcore.last_update_clock;
 396         lc->ftrace_func = S390_lowcore.ftrace_func;
 397         set_prefix((u32)(unsigned long) lc);
 398         lowcore_ptr[0] = lc;
 399 }
 400
 401 static struct resource code_resource = {
 402         .name  = "Kernel code",
 403         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 404 };
 405
 406 static struct resource data_resource = {
 407         .name = "Kernel data",
 408         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 409 };
 410
 411 static struct resource bss_resource = {
 412         .name = "Kernel bss",
 413         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 414 };
 415
 416 static struct resource __initdata *standard_resources[] = {
 417         &code_resource,
 418         &data_resource,
 419         &bss_resource,
 420 };
 421
 422 static void __init setup_resources(void)
 423 {
 424         struct resource *res, *std_res, *sub_res;
 425         int i, j;
 426
 427         code_resource.start = (unsigned long) &_text;
 428         code_resource.end = (unsigned long) &_etext - 1;
 429         data_resource.start = (unsigned long) &_etext;
 430         data_resource.end = (unsigned long) &_edata - 1;
 431         bss_resource.start = (unsigned long) &__bss_start;
 432         bss_resource.end = (unsigned long) &__bss_stop - 1;
 433
 434         for (i = 0; i < MEMORY_CHUNKS; i++) {
 435                 if (!memory_chunk[i].size)
 436                         continue;
 437                 if (memory_chunk[i].type == CHUNK_OLDMEM ||
 438                     memory_chunk[i].type == CHUNK_CRASHK)
 439                         continue;
 440                 res = alloc_bootmem_low(sizeof(*res));
 441                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 442                 switch (memory_chunk[i].type) {
 443                 case CHUNK_READ_WRITE:
 444                 case CHUNK_CRASHK:
 445                         res->name = "System RAM";
 446                         break;
 447                 case CHUNK_READ_ONLY:
 448                         res->name = "System ROM";
 449                         res->flags |= IORESOURCE_READONLY;
 450                         break;
 451                 default:
 452                         res->name = "reserved";
 453                 }
 454                 res->start = memory_chunk[i].addr;
 455                 res->end = res->start + memory_chunk[i].size - 1;
 456                 request_resource(&iomem_resource, res);
 457
 458                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 459                         std_res = standard_resources[j];
 460                         if (std_res->start < res->start ||
 461                             std_res->start > res->end)
 462                                 continue;
 463                         if (std_res->end > res->end) {
 464                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 465                                 *sub_res = *std_res;
 466                                 sub_res->end = res->end;
 467                                 std_res->start = res->end + 1;
 468                                 request_resource(res, sub_res);
 469                         } else {
 470                                 request_resource(res, std_res);
 471                         }
 472                 }
 473         }
 474 }
 475
 476 unsigned long real_memory_size;
 477 EXPORT_SYMBOL_GPL(real_memory_size);
 478
 479 static void __init setup_memory_end(void)
 480 {
 481         unsigned long memory_size;
 482         unsigned long max_mem;
 483         int i;
 484
 485
 486 #ifdef CONFIG_ZFCPDUMP
 487         if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
 488                 memory_end = ZFCPDUMP_HSA_SIZE;
 489                 memory_end_set = 1;
 490         }
 491 #endif
 492         memory_size = 0;
 493         memory_end &= PAGE_MASK;
 494
 495         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 496         memory_end = min(max_mem, memory_end);
 497
 498         /*
 499          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 500          * extra checks that HOLES_IN_ZONE would require.
 501          */
 502         for (i = 0; i < MEMORY_CHUNKS; i++) {
 503                 unsigned long start, end;
 504                 struct mem_chunk *chunk;
 505                 unsigned long align;
 506
 507                 chunk = &memory_chunk[i];
 508                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 509                 start = (chunk->addr + align - 1) & ~(align - 1);
 510                 end = (chunk->addr + chunk->size) & ~(align - 1);
 511                 if (start >= end)
 512                         memset(chunk, 0, sizeof(*chunk));
 513                 else {
 514                         chunk->addr = start;
 515                         chunk->size = end - start;
 516                 }
 517         }
 518
 519         for (i = 0; i < MEMORY_CHUNKS; i++) {
 520                 struct mem_chunk *chunk = &memory_chunk[i];
 521
 522                 real_memory_size = max(real_memory_size,
 523                                        chunk->addr + chunk->size);
 524                 if (chunk->addr >= max_mem) {
 525                         memset(chunk, 0, sizeof(*chunk));
 526                         continue;
 527                 }
 528                 if (chunk->addr + chunk->size > max_mem)
 529                         chunk->size = max_mem - chunk->addr;
 530                 memory_size = max(memory_size, chunk->addr + chunk->size);
 531         }
 532         if (!memory_end)
 533                 memory_end = memory_size;
 534 }
 535
 536 void *restart_stack __attribute__((__section__(".data")));
 537
 538 /*
 539  * Setup new PSW and allocate stack for PSW restart interrupt
 540  */
 541 static void __init setup_restart_psw(void)
 542 {
 543         psw_t psw;
 544
 545         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
 546         restart_stack += ASYNC_SIZE;
 547
 548         /*
 549          * Setup restart PSW for absolute zero lowcore. This is necesary
 550          * if PSW restart is done on an offline CPU that has lowcore zero
 551          */
 552         psw.mask = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA;
 553         psw.addr = PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 554         copy_to_absolute_zero(&S390_lowcore.restart_psw, &psw, sizeof(psw));
 555 }
 556
 557 static void __init setup_vmcoreinfo(void)
 558 {
 559 #ifdef CONFIG_KEXEC
 560         unsigned long ptr = paddr_vmcoreinfo_note();
 561
 562         copy_to_absolute_zero(&S390_lowcore.vmcore_info, &ptr, sizeof(ptr));
 563 #endif
 564 }
 565
 566 #ifdef CONFIG_CRASH_DUMP
 567
 568 /*
 569  * Find suitable location for crashkernel memory
 570  */
 571 static unsigned long __init find_crash_base(unsigned long crash_size,
 572                                             char **msg)
 573 {
 574         unsigned long crash_base;
 575         struct mem_chunk *chunk;
 576         int i;
 577
 578         if (memory_chunk[0].size < crash_size) {
 579                 *msg = "first memory chunk must be at least crashkernel size";
 580                 return 0;
 581         }
 582         if (is_kdump_kernel() && (crash_size == OLDMEM_SIZE))
 583                 return OLDMEM_BASE;
 584
 585         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
 586                 chunk = &memory_chunk[i];
 587                 if (chunk->size == 0)
 588                         continue;
 589                 if (chunk->type != CHUNK_READ_WRITE)
 590                         continue;
 591                 if (chunk->size < crash_size)
 592                         continue;
 593                 crash_base = (chunk->addr + chunk->size) - crash_size;
 594                 if (crash_base < crash_size)
 595                         continue;
 596                 if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
 597                         continue;
 598                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 599                         continue;
 600                 return crash_base;
 601         }
 602         *msg = "no suitable area found";
 603         return 0;
 604 }
 605
 606 /*
 607  * Check if crash_base and crash_size is valid
 608  */
 609 static int __init verify_crash_base(unsigned long crash_base,
 610                                     unsigned long crash_size,
 611                                     char **msg)
 612 {
 613         struct mem_chunk *chunk;
 614         int i;
 615
 616         /*
 617          * Because we do the swap to zero, we must have at least 'crash_size'
 618          * bytes free space before crash_base
 619          */
 620         if (crash_size > crash_base) {
 621                 *msg = "crashkernel offset must be greater than size";
 622                 return -EINVAL;
 623         }
 624
 625         /* First memory chunk must be at least crash_size */
 626         if (memory_chunk[0].size < crash_size) {
 627                 *msg = "first memory chunk must be at least crashkernel size";
 628                 return -EINVAL;
 629         }
 630         /* Check if we fit into the respective memory chunk */
 631         for (i = 0; i < MEMORY_CHUNKS; i++) {
 632                 chunk = &memory_chunk[i];
 633                 if (chunk->size == 0)
 634                         continue;
 635                 if (crash_base < chunk->addr)
 636                         continue;
 637                 if (crash_base >= chunk->addr + chunk->size)
 638                         continue;
 639                 /* we have found the memory chunk */
 640                 if (crash_base + crash_size > chunk->addr + chunk->size) {
 641                         *msg = "selected memory chunk is too small for "
 642                                 "crashkernel memory";
 643                         return -EINVAL;
 644                 }
 645                 return 0;
 646         }
 647         *msg = "invalid memory range specified";
 648         return -EINVAL;
 649 }
 650
 651 /*
 652  * Reserve kdump memory by creating a memory hole in the mem_chunk array
 653  */
 654 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
 655                                          int type)
 656 {
 657
 658         create_mem_hole(memory_chunk, addr, size, type);
 659 }
 660
 661 /*
 662  * When kdump is enabled, we have to ensure that no memory from
 663  * the area [0 - crashkernel memory size] and
 664  * [crashk_res.start - crashk_res.end] is set offline.
 665  */
 666 static int kdump_mem_notifier(struct notifier_block *nb,
 667                               unsigned long action, void *data)
 668 {
 669         struct memory_notify *arg = data;
 670
 671         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 672                 return NOTIFY_BAD;
 673         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 674                 return NOTIFY_OK;
 675         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 676                 return NOTIFY_OK;
 677         return NOTIFY_BAD;
 678 }
 679
 680 static struct notifier_block kdump_mem_nb = {
 681         .notifier_call = kdump_mem_notifier,
 682 };
 683
 684 #endif
 685
 686 /*
 687  * Make sure that oldmem, where the dump is stored, is protected
 688  */
 689 static void reserve_oldmem(void)
 690 {
 691 #ifdef CONFIG_CRASH_DUMP
 692         if (!OLDMEM_BASE)
 693                 return;
 694
 695         reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
 696         reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
 697                               CHUNK_OLDMEM);
 698         if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
 699                 saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
 700         else
 701                 saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
 702 #endif
 703 }
 704
 705 /*
 706  * Reserve memory for kdump kernel to be loaded with kexec
 707  */
 708 static void __init reserve_crashkernel(void)
 709 {
 710 #ifdef CONFIG_CRASH_DUMP
 711         unsigned long long crash_base, crash_size;
 712         char *msg;
 713         int rc;
 714
 715         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 716                                &crash_base);
 717         if (rc || crash_size == 0)
 718                 return;
 719         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 720         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 721         if (register_memory_notifier(&kdump_mem_nb))
 722                 return;
 723         if (!crash_base)
 724                 crash_base = find_crash_base(crash_size, &msg);
 725         if (!crash_base) {
 726                 pr_info("crashkernel reservation failed: %s\n", msg);
 727                 unregister_memory_notifier(&kdump_mem_nb);
 728                 return;
 729         }
 730         if (verify_crash_base(crash_base, crash_size, &msg)) {
 731                 pr_info("crashkernel reservation failed: %s\n", msg);
 732                 unregister_memory_notifier(&kdump_mem_nb);
 733                 return;
 734         }
 735         if (!OLDMEM_BASE && MACHINE_IS_VM)
 736                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 737         crashk_res.start = crash_base;
 738         crashk_res.end = crash_base + crash_size - 1;
 739         insert_resource(&iomem_resource, &crashk_res);
 740         reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
 741         pr_info("Reserving %lluMB of memory at %lluMB "
 742                 "for crashkernel (System RAM: %luMB)\n",
 743                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
 744 #endif
 745 }
 746
 747 static void __init
 748 setup_memory(void)
 749 {
 750         unsigned long bootmap_size;
 751         unsigned long start_pfn, end_pfn;
 752         int i;
 753
 754         /*
 755          * partially used pages are not usable - thus
 756          * we are rounding upwards:
 757          */
 758         start_pfn = PFN_UP(__pa(&_end));
 759         end_pfn = max_pfn = PFN_DOWN(memory_end);
 760
 761 #ifdef CONFIG_BLK_DEV_INITRD
 762         /*
 763          * Move the initrd in case the bitmap of the bootmem allocater
 764          * would overwrite it.
 765          */
 766
 767         if (INITRD_START && INITRD_SIZE) {
 768                 unsigned long bmap_size;
 769                 unsigned long start;
 770
 771                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 772                 bmap_size = PFN_PHYS(bmap_size);
 773
 774                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 775                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 776
 777 #ifdef CONFIG_CRASH_DUMP
 778                         if (OLDMEM_BASE) {
 779                                 /* Move initrd behind kdump oldmem */
 780                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
 781                                     start < OLDMEM_BASE + OLDMEM_SIZE)
 782                                         start = OLDMEM_BASE + OLDMEM_SIZE;
 783                         }
 784 #endif
 785                         if (start + INITRD_SIZE > memory_end) {
 786                                 pr_err("initrd extends beyond end of "
 787                                        "memory (0x%08lx > 0x%08lx) "
 788                                        "disabling initrd\n",
 789                                        start + INITRD_SIZE, memory_end);
 790                                 INITRD_START = INITRD_SIZE = 0;
 791                         } else {
 792                                 pr_info("Moving initrd (0x%08lx -> "
 793                                         "0x%08lx, size: %ld)\n",
 794                                         INITRD_START, start, INITRD_SIZE);
 795                                 memmove((void *) start, (void *) INITRD_START,
 796                                         INITRD_SIZE);
 797                                 INITRD_START = start;
 798                         }
 799                 }
 800         }
 801 #endif
 802
 803         /*
 804          * Initialize the boot-time allocator
 805          */
 806         bootmap_size = init_bootmem(start_pfn, end_pfn);
 807
 808         /*
 809          * Register RAM areas with the bootmem allocator.
 810          */
 811
 812         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 813                 unsigned long start_chunk, end_chunk, pfn;
 814
 815                 if (memory_chunk[i].type != CHUNK_READ_WRITE &&
 816                     memory_chunk[i].type != CHUNK_CRASHK)
 817                         continue;
 818                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 819                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 820                 end_chunk = min(end_chunk, end_pfn);
 821                 if (start_chunk >= end_chunk)
 822                         continue;
 823                 add_active_range(0, start_chunk, end_chunk);
 824                 pfn = max(start_chunk, start_pfn);
 825                 for (; pfn < end_chunk; pfn++)
 826                         page_set_storage_key(PFN_PHYS(pfn),
 827                                              PAGE_DEFAULT_KEY, 0);
 828         }
 829
 830         psw_set_key(PAGE_DEFAULT_KEY);
 831
 832         free_bootmem_with_active_regions(0, max_pfn);
 833
 834         /*
 835          * Reserve memory used for lowcore/command line/kernel image.
 836          */
 837         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 838         reserve_bootmem((unsigned long)_stext,
 839                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 840                         BOOTMEM_DEFAULT);
 841         /*
 842          * Reserve the bootmem bitmap itself as well. We do this in two
 843          * steps (first step was init_bootmem()) because this catches
 844          * the (very unlikely) case of us accidentally initializing the
 845          * bootmem allocator with an invalid RAM area.
 846          */
 847         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 848                         BOOTMEM_DEFAULT);
 849
 850 #ifdef CONFIG_CRASH_DUMP
 851         if (crashk_res.start)
 852                 reserve_bootmem(crashk_res.start,
 853                                 crashk_res.end - crashk_res.start + 1,
 854                                 BOOTMEM_DEFAULT);
 855         if (is_kdump_kernel())
 856                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
 857                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
 858 #endif
 859 #ifdef CONFIG_BLK_DEV_INITRD
 860         if (INITRD_START && INITRD_SIZE) {
 861                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 862                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 863                                         BOOTMEM_DEFAULT);
 864                         initrd_start = INITRD_START;
 865                         initrd_end = initrd_start + INITRD_SIZE;
 866                 } else {
 867                         pr_err("initrd extends beyond end of "
 868                                "memory (0x%08lx > 0x%08lx) "
 869                                "disabling initrd\n",
 870                                initrd_start + INITRD_SIZE, memory_end);
 871                         initrd_start = initrd_end = 0;
 872                 }
 873         }
 874 #endif
 875 }
 876
 877 /*
 878  * Setup hardware capabilities.
 879  */
 880 static void __init setup_hwcaps(void)
 881 {
 882         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 883         struct cpuid cpu_id;
 884         int i;
 885
 886         /*
 887          * The store facility list bits numbers as found in the principles
 888          * of operation are numbered with bit 1UL<<31 as number 0 to
 889          * bit 1UL<<0 as number 31.
 890          *   Bit 0: instructions named N3, "backported" to esa-mode
 891          *   Bit 2: z/Architecture mode is active
 892          *   Bit 7: the store-facility-list-extended facility is installed
 893          *   Bit 17: the message-security assist is installed
 894          *   Bit 19: the long-displacement facility is installed
 895          *   Bit 21: the extended-immediate facility is installed
 896          *   Bit 22: extended-translation facility 3 is installed
 897          *   Bit 30: extended-translation facility 3 enhancement facility
 898          * These get translated to:
 899          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 900          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 901          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 902          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 903          */
 904         for (i = 0; i < 6; i++)
 905                 if (test_facility(stfl_bits[i]))
 906                         elf_hwcap |= 1UL << i;
 907
 908         if (test_facility(22) && test_facility(30))
 909                 elf_hwcap |= HWCAP_S390_ETF3EH;
 910
 911         /*
 912          * Check for additional facilities with store-facility-list-extended.
 913          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 914          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 915          * as stored by stfl, bits 32-xxx contain additional facilities.
 916          * How many facility words are stored depends on the number of
 917          * doublewords passed to the instruction. The additional facilities
 918          * are:
 919          *   Bit 42: decimal floating point facility is installed
 920          *   Bit 44: perform floating point operation facility is installed
 921          * translated to:
 922          *   HWCAP_S390_DFP bit 6 (42 && 44).
 923          */
 924         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 925                 elf_hwcap |= HWCAP_S390_DFP;
 926
 927         /*
 928          * Huge page support HWCAP_S390_HPAGE is bit 7.
 929          */
 930         if (MACHINE_HAS_HPAGE)
 931                 elf_hwcap |= HWCAP_S390_HPAGE;
 932
 933         /*
 934          * 64-bit register support for 31-bit processes
 935          * HWCAP_S390_HIGH_GPRS is bit 9.
 936          */
 937         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 938
 939         get_cpu_id(&cpu_id);
 940         switch (cpu_id.machine) {
 941         case 0x9672:
 942 #if !defined(CONFIG_64BIT)
 943         default:        /* Use "g5" as default for 31 bit kernels. */
 944 #endif
 945                 strcpy(elf_platform, "g5");
 946                 break;
 947         case 0x2064:
 948         case 0x2066:
 949 #if defined(CONFIG_64BIT)
 950         default:        /* Use "z900" as default for 64 bit kernels. */
 951 #endif
 952                 strcpy(elf_platform, "z900");
 953                 break;
 954         case 0x2084:
 955         case 0x2086:
 956                 strcpy(elf_platform, "z990");
 957                 break;
 958         case 0x2094:
 959         case 0x2096:
 960                 strcpy(elf_platform, "z9-109");
 961                 break;
 962         case 0x2097:
 963         case 0x2098:
 964                 strcpy(elf_platform, "z10");
 965                 break;
 966         case 0x2817:
 967         case 0x2818:
 968                 strcpy(elf_platform, "z196");
 969                 break;
 970         }
 971 }
 972
 973 /*
 974  * Setup function called from init/main.c just after the banner
 975  * was printed.
 976  */
 977
 978 void __init
 979 setup_arch(char **cmdline_p)
 980 {
 981         /*
 982          * print what head.S has found out about the machine
 983          */
 984 #ifndef CONFIG_64BIT
 985         if (MACHINE_IS_VM)
 986                 pr_info("Linux is running as a z/VM "
 987                         "guest operating system in 31-bit mode\n");
 988         else if (MACHINE_IS_LPAR)
 989                 pr_info("Linux is running natively in 31-bit mode\n");
 990         if (MACHINE_HAS_IEEE)
 991                 pr_info("The hardware system has IEEE compatible "
 992                         "floating point units\n");
 993         else
 994                 pr_info("The hardware system has no IEEE compatible "
 995                         "floating point units\n");
 996 #else /* CONFIG_64BIT */
 997         if (MACHINE_IS_VM)
 998                 pr_info("Linux is running as a z/VM "
 999                         "guest operating system in 64-bit mode\n");
1000         else if (MACHINE_IS_KVM)
1001                 pr_info("Linux is running under KVM in 64-bit mode\n");
1002         else if (MACHINE_IS_LPAR)
1003                 pr_info("Linux is running natively in 64-bit mode\n");
1004 #endif /* CONFIG_64BIT */
1005
1006         /* Have one command line that is parsed and saved in /proc/cmdline */
1007         /* boot_command_line has been already set up in early.c */
1008         *cmdline_p = boot_command_line;
1009
1010         ROOT_DEV = Root_RAM0;
1011
1012         init_mm.start_code = PAGE_OFFSET;
1013         init_mm.end_code = (unsigned long) &_etext;
1014         init_mm.end_data = (unsigned long) &_edata;
1015         init_mm.brk = (unsigned long) &_end;
1016
1017         if (MACHINE_HAS_MVCOS)
1018                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1019         else
1020                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1021
1022         parse_early_param();
1023
1024         setup_ipl();
1025         setup_memory_end();
1026         setup_addressing_mode();
1027         reserve_oldmem();
1028         reserve_crashkernel();
1029         setup_memory();
1030         setup_resources();
1031         setup_vmcoreinfo();
1032         setup_restart_psw();
1033         setup_lowcore();
1034
1035         cpu_init();
1036         s390_init_cpu_topology();
1037
1038         /*
1039          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1040          */
1041         setup_hwcaps();
1042
1043         /*
1044          * Create kernel page tables and switch to virtual addressing.
1045          */
1046         paging_init();
1047
1048         /* Setup default console */
1049         conmode_default();
1050         set_preferred_console();
1051
1052         /* Setup zfcpdump support */
1053         setup_zfcpdump(console_devno);
1054 }