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/memblock.h>
  25 #include <linux/mm.h>
  26 #include <linux/stddef.h>
  27 #include <linux/unistd.h>
  28 #include <linux/ptrace.h>
  29 #include <linux/user.h>
  30 #include <linux/tty.h>
  31 #include <linux/ioport.h>
  32 #include <linux/delay.h>
  33 #include <linux/init.h>
  34 #include <linux/initrd.h>
  35 #include <linux/bootmem.h>
  36 #include <linux/root_dev.h>
  37 #include <linux/console.h>
  38 #include <linux/kernel_stat.h>
  39 #include <linux/device.h>
  40 #include <linux/notifier.h>
  41 #include <linux/pfn.h>
  42 #include <linux/ctype.h>
  43 #include <linux/reboot.h>
  44 #include <linux/topology.h>
  45 #include <linux/ftrace.h>
  46 #include <linux/kexec.h>
  47 #include <linux/crash_dump.h>
  48 #include <linux/memory.h>
  49
  50 #include <asm/ipl.h>
  51 #include <asm/uaccess.h>
  52 #include <asm/system.h>
  53 #include <asm/smp.h>
  54 #include <asm/mmu_context.h>
  55 #include <asm/cpcmd.h>
  56 #include <asm/lowcore.h>
  57 #include <asm/irq.h>
  58 #include <asm/page.h>
  59 #include <asm/ptrace.h>
  60 #include <asm/sections.h>
  61 #include <asm/ebcdic.h>
  62 #include <asm/compat.h>
  63 #include <asm/kvm_virtio.h>
  64 #include <asm/diag.h>
  65
  66 long psw_kernel_bits    = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
  67                           PSW_MASK_EA | PSW_MASK_BA;
  68 long psw_user_bits      = PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
  69                           PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
  70                           PSW_MASK_PSTATE | PSW_ASC_HOME;
  71
  72 /*
  73  * User copy operations.
  74  */
  75 struct uaccess_ops uaccess;
  76 EXPORT_SYMBOL(uaccess);
  77
  78 /*
  79  * Machine setup..
  80  */
  81 unsigned int console_mode = 0;
  82 EXPORT_SYMBOL(console_mode);
  83
  84 unsigned int console_devno = -1;
  85 EXPORT_SYMBOL(console_devno);
  86
  87 unsigned int console_irq = -1;
  88 EXPORT_SYMBOL(console_irq);
  89
  90 unsigned long elf_hwcap = 0;
  91 char elf_platform[ELF_PLATFORM_SIZE];
  92
  93 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  94
  95 int __initdata memory_end_set;
  96 unsigned long __initdata memory_end;
  97
  98 /* An array with a pointer to the lowcore of every CPU. */
  99 struct _lowcore *lowcore_ptr[NR_CPUS];
 100 EXPORT_SYMBOL(lowcore_ptr);
 101
 102 /*
 103  * This is set up by the setup-routine at boot-time
 104  * for S390 need to find out, what we have to setup
 105  * using address 0x10400 ...
 106  */
 107
 108 #include <asm/setup.h>
 109
 110 /*
 111  * condev= and conmode= setup parameter.
 112  */
 113
 114 static int __init condev_setup(char *str)
 115 {
 116         int vdev;
 117
 118         vdev = simple_strtoul(str, &str, 0);
 119         if (vdev >= 0 && vdev < 65536) {
 120                 console_devno = vdev;
 121                 console_irq = -1;
 122         }
 123         return 1;
 124 }
 125
 126 __setup("condev=", condev_setup);
 127
 128 static void __init set_preferred_console(void)
 129 {
 130         if (MACHINE_IS_KVM)
 131                 add_preferred_console("hvc", 0, NULL);
 132         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 133                 add_preferred_console("ttyS", 0, NULL);
 134         else if (CONSOLE_IS_3270)
 135                 add_preferred_console("tty3270", 0, NULL);
 136 }
 137
 138 static int __init conmode_setup(char *str)
 139 {
 140 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 141         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 142                 SET_CONSOLE_SCLP;
 143 #endif
 144 #if defined(CONFIG_TN3215_CONSOLE)
 145         if (strncmp(str, "3215", 5) == 0)
 146                 SET_CONSOLE_3215;
 147 #endif
 148 #if defined(CONFIG_TN3270_CONSOLE)
 149         if (strncmp(str, "3270", 5) == 0)
 150                 SET_CONSOLE_3270;
 151 #endif
 152         set_preferred_console();
 153         return 1;
 154 }
 155
 156 __setup("conmode=", conmode_setup);
 157
 158 static void __init conmode_default(void)
 159 {
 160         char query_buffer[1024];
 161         char *ptr;
 162
 163         if (MACHINE_IS_VM) {
 164                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 165                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 166                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 167                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 168                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 169                 ptr = strstr(query_buffer, "CONMODE");
 170                 /*
 171                  * Set the conmode to 3215 so that the device recognition
 172                  * will set the cu_type of the console to 3215. If the
 173                  * conmode is 3270 and we don't set it back then both
 174                  * 3215 and the 3270 driver will try to access the console
 175                  * device (3215 as console and 3270 as normal tty).
 176                  */
 177                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 178                 if (ptr == NULL) {
 179 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 180                         SET_CONSOLE_SCLP;
 181 #endif
 182                         return;
 183                 }
 184                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 185 #if defined(CONFIG_TN3270_CONSOLE)
 186                         SET_CONSOLE_3270;
 187 #elif defined(CONFIG_TN3215_CONSOLE)
 188                         SET_CONSOLE_3215;
 189 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 190                         SET_CONSOLE_SCLP;
 191 #endif
 192                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 193 #if defined(CONFIG_TN3215_CONSOLE)
 194                         SET_CONSOLE_3215;
 195 #elif defined(CONFIG_TN3270_CONSOLE)
 196                         SET_CONSOLE_3270;
 197 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 198                         SET_CONSOLE_SCLP;
 199 #endif
 200                 }
 201         } else {
 202 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 203                 SET_CONSOLE_SCLP;
 204 #endif
 205         }
 206 }
 207
 208 #ifdef CONFIG_ZFCPDUMP
 209 static void __init setup_zfcpdump(unsigned int console_devno)
 210 {
 211         static char str[41];
 212
 213         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 214                 return;
 215         if (OLDMEM_BASE)
 216                 return;
 217         if (console_devno != -1)
 218                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 219                         ipl_info.data.fcp.dev_id.devno, console_devno);
 220         else
 221                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 222                         ipl_info.data.fcp.dev_id.devno);
 223         strcat(boot_command_line, str);
 224         console_loglevel = 2;
 225 }
 226 #else
 227 static inline void setup_zfcpdump(unsigned int console_devno) {}
 228 #endif /* CONFIG_ZFCPDUMP */
 229
 230  /*
 231  * Reboot, halt and power_off stubs. They just call _machine_restart,
 232  * _machine_halt or _machine_power_off.
 233  */
 234
 235 void machine_restart(char *command)
 236 {
 237         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 238                 /*
 239                  * Only unblank the console if we are called in enabled
 240                  * context or a bust_spinlocks cleared the way for us.
 241                  */
 242                 console_unblank();
 243         _machine_restart(command);
 244 }
 245
 246 void machine_halt(void)
 247 {
 248         if (!in_interrupt() || oops_in_progress)
 249                 /*
 250                  * Only unblank the console if we are called in enabled
 251                  * context or a bust_spinlocks cleared the way for us.
 252                  */
 253                 console_unblank();
 254         _machine_halt();
 255 }
 256
 257 void machine_power_off(void)
 258 {
 259         if (!in_interrupt() || oops_in_progress)
 260                 /*
 261                  * Only unblank the console if we are called in enabled
 262                  * context or a bust_spinlocks cleared the way for us.
 263                  */
 264                 console_unblank();
 265         _machine_power_off();
 266 }
 267
 268 /*
 269  * Dummy power off function.
 270  */
 271 void (*pm_power_off)(void) = machine_power_off;
 272
 273 static int __init early_parse_mem(char *p)
 274 {
 275         memory_end = memparse(p, &p);
 276         memory_end_set = 1;
 277         return 0;
 278 }
 279 early_param("mem", early_parse_mem);
 280
 281 unsigned int user_mode = HOME_SPACE_MODE;
 282 EXPORT_SYMBOL_GPL(user_mode);
 283
 284 static int set_amode_primary(void)
 285 {
 286         psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
 287         psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
 288 #ifdef CONFIG_COMPAT
 289         psw32_user_bits =
 290                 (psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
 291 #endif
 292
 293         if (MACHINE_HAS_MVCOS) {
 294                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 295                 return 1;
 296         } else {
 297                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 298                 return 0;
 299         }
 300 }
 301
 302 /*
 303  * Switch kernel/user addressing modes?
 304  */
 305 static int __init early_parse_switch_amode(char *p)
 306 {
 307         user_mode = PRIMARY_SPACE_MODE;
 308         return 0;
 309 }
 310 early_param("switch_amode", early_parse_switch_amode);
 311
 312 static int __init early_parse_user_mode(char *p)
 313 {
 314         if (p && strcmp(p, "primary") == 0)
 315                 user_mode = PRIMARY_SPACE_MODE;
 316         else if (!p || strcmp(p, "home") == 0)
 317                 user_mode = HOME_SPACE_MODE;
 318         else
 319                 return 1;
 320         return 0;
 321 }
 322 early_param("user_mode", early_parse_user_mode);
 323
 324 static void setup_addressing_mode(void)
 325 {
 326         if (user_mode == PRIMARY_SPACE_MODE) {
 327                 if (set_amode_primary())
 328                         pr_info("Address spaces switched, "
 329                                 "mvcos available\n");
 330                 else
 331                         pr_info("Address spaces switched, "
 332                                 "mvcos not available\n");
 333         }
 334 }
 335
 336 static void __init
 337 setup_lowcore(void)
 338 {
 339         struct _lowcore *lc;
 340
 341         /*
 342          * Setup lowcore for boot cpu
 343          */
 344         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 345         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 346         lc->restart_psw.mask = psw_kernel_bits;
 347         lc->restart_psw.addr =
 348                 PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 349         lc->external_new_psw.mask = psw_kernel_bits |
 350                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 351         lc->external_new_psw.addr =
 352                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 353         lc->svc_new_psw.mask = psw_kernel_bits |
 354                 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 355         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 356         lc->program_new_psw.mask = psw_kernel_bits |
 357                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 358         lc->program_new_psw.addr =
 359                 PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
 360         lc->mcck_new_psw.mask = psw_kernel_bits;
 361         lc->mcck_new_psw.addr =
 362                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 363         lc->io_new_psw.mask = psw_kernel_bits |
 364                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 365         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 366         lc->clock_comparator = -1ULL;
 367         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 368         lc->async_stack = (unsigned long)
 369                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 370         lc->panic_stack = (unsigned long)
 371                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 372         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 373         lc->thread_info = (unsigned long) &init_thread_union;
 374         lc->machine_flags = S390_lowcore.machine_flags;
 375         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 376         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 377                MAX_FACILITY_BIT/8);
 378 #ifndef CONFIG_64BIT
 379         if (MACHINE_HAS_IEEE) {
 380                 lc->extended_save_area_addr = (__u32)
 381                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 382                 /* enable extended save area */
 383                 __ctl_set_bit(14, 29);
 384         }
 385 #else
 386         lc->cmf_hpp = -1ULL;
 387         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 388 #endif
 389         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 390         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 391         lc->exit_timer = S390_lowcore.exit_timer;
 392         lc->user_timer = S390_lowcore.user_timer;
 393         lc->system_timer = S390_lowcore.system_timer;
 394         lc->steal_timer = S390_lowcore.steal_timer;
 395         lc->last_update_timer = S390_lowcore.last_update_timer;
 396         lc->last_update_clock = S390_lowcore.last_update_clock;
 397         lc->ftrace_func = S390_lowcore.ftrace_func;
 398         set_prefix((u32)(unsigned long) lc);
 399         lowcore_ptr[0] = lc;
 400 }
 401
 402 static struct resource code_resource = {
 403         .name  = "Kernel code",
 404         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 405 };
 406
 407 static struct resource data_resource = {
 408         .name = "Kernel data",
 409         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 410 };
 411
 412 static struct resource bss_resource = {
 413         .name = "Kernel bss",
 414         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 415 };
 416
 417 static struct resource __initdata *standard_resources[] = {
 418         &code_resource,
 419         &data_resource,
 420         &bss_resource,
 421 };
 422
 423 static void __init setup_resources(void)
 424 {
 425         struct resource *res, *std_res, *sub_res;
 426         int i, j;
 427
 428         code_resource.start = (unsigned long) &_text;
 429         code_resource.end = (unsigned long) &_etext - 1;
 430         data_resource.start = (unsigned long) &_etext;
 431         data_resource.end = (unsigned long) &_edata - 1;
 432         bss_resource.start = (unsigned long) &__bss_start;
 433         bss_resource.end = (unsigned long) &__bss_stop - 1;
 434
 435         for (i = 0; i < MEMORY_CHUNKS; i++) {
 436                 if (!memory_chunk[i].size)
 437                         continue;
 438                 if (memory_chunk[i].type == CHUNK_OLDMEM ||
 439                     memory_chunk[i].type == CHUNK_CRASHK)
 440                         continue;
 441                 res = alloc_bootmem_low(sizeof(*res));
 442                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 443                 switch (memory_chunk[i].type) {
 444                 case CHUNK_READ_WRITE:
 445                 case CHUNK_CRASHK:
 446                         res->name = "System RAM";
 447                         break;
 448                 case CHUNK_READ_ONLY:
 449                         res->name = "System ROM";
 450                         res->flags |= IORESOURCE_READONLY;
 451                         break;
 452                 default:
 453                         res->name = "reserved";
 454                 }
 455                 res->start = memory_chunk[i].addr;
 456                 res->end = res->start + memory_chunk[i].size - 1;
 457                 request_resource(&iomem_resource, res);
 458
 459                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 460                         std_res = standard_resources[j];
 461                         if (std_res->start < res->start ||
 462                             std_res->start > res->end)
 463                                 continue;
 464                         if (std_res->end > res->end) {
 465                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 466                                 *sub_res = *std_res;
 467                                 sub_res->end = res->end;
 468                                 std_res->start = res->end + 1;
 469                                 request_resource(res, sub_res);
 470                         } else {
 471                                 request_resource(res, std_res);
 472                         }
 473                 }
 474         }
 475 }
 476
 477 unsigned long real_memory_size;
 478 EXPORT_SYMBOL_GPL(real_memory_size);
 479
 480 static void __init setup_memory_end(void)
 481 {
 482         unsigned long memory_size;
 483         unsigned long max_mem;
 484         int i;
 485
 486
 487 #ifdef CONFIG_ZFCPDUMP
 488         if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
 489                 memory_end = ZFCPDUMP_HSA_SIZE;
 490                 memory_end_set = 1;
 491         }
 492 #endif
 493         memory_size = 0;
 494         memory_end &= PAGE_MASK;
 495
 496         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 497         memory_end = min(max_mem, memory_end);
 498
 499         /*
 500          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 501          * extra checks that HOLES_IN_ZONE would require.
 502          */
 503         for (i = 0; i < MEMORY_CHUNKS; i++) {
 504                 unsigned long start, end;
 505                 struct mem_chunk *chunk;
 506                 unsigned long align;
 507
 508                 chunk = &memory_chunk[i];
 509                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 510                 start = (chunk->addr + align - 1) & ~(align - 1);
 511                 end = (chunk->addr + chunk->size) & ~(align - 1);
 512                 if (start >= end)
 513                         memset(chunk, 0, sizeof(*chunk));
 514                 else {
 515                         chunk->addr = start;
 516                         chunk->size = end - start;
 517                 }
 518         }
 519
 520         for (i = 0; i < MEMORY_CHUNKS; i++) {
 521                 struct mem_chunk *chunk = &memory_chunk[i];
 522
 523                 real_memory_size = max(real_memory_size,
 524                                        chunk->addr + chunk->size);
 525                 if (chunk->addr >= max_mem) {
 526                         memset(chunk, 0, sizeof(*chunk));
 527                         continue;
 528                 }
 529                 if (chunk->addr + chunk->size > max_mem)
 530                         chunk->size = max_mem - chunk->addr;
 531                 memory_size = max(memory_size, chunk->addr + chunk->size);
 532         }
 533         if (!memory_end)
 534                 memory_end = memory_size;
 535 }
 536
 537 void *restart_stack __attribute__((__section__(".data")));
 538
 539 /*
 540  * Setup new PSW and allocate stack for PSW restart interrupt
 541  */
 542 static void __init setup_restart_psw(void)
 543 {
 544         psw_t psw;
 545
 546         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
 547         restart_stack += ASYNC_SIZE;
 548
 549         /*
 550          * Setup restart PSW for absolute zero lowcore. This is necesary
 551          * if PSW restart is done on an offline CPU that has lowcore zero
 552          */
 553         psw.mask = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA;
 554         psw.addr = PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
 555         copy_to_absolute_zero(&S390_lowcore.restart_psw, &psw, sizeof(psw));
 556 }
 557
 558 static void __init setup_vmcoreinfo(void)
 559 {
 560 #ifdef CONFIG_KEXEC
 561         unsigned long ptr = paddr_vmcoreinfo_note();
 562
 563         copy_to_absolute_zero(&S390_lowcore.vmcore_info, &ptr, sizeof(ptr));
 564 #endif
 565 }
 566
 567 #ifdef CONFIG_CRASH_DUMP
 568
 569 /*
 570  * Find suitable location for crashkernel memory
 571  */
 572 static unsigned long __init find_crash_base(unsigned long crash_size,
 573                                             char **msg)
 574 {
 575         unsigned long crash_base;
 576         struct mem_chunk *chunk;
 577         int i;
 578
 579         if (memory_chunk[0].size < crash_size) {
 580                 *msg = "first memory chunk must be at least crashkernel size";
 581                 return 0;
 582         }
 583         if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
 584                 return OLDMEM_BASE;
 585
 586         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
 587                 chunk = &memory_chunk[i];
 588                 if (chunk->size == 0)
 589                         continue;
 590                 if (chunk->type != CHUNK_READ_WRITE)
 591                         continue;
 592                 if (chunk->size < crash_size)
 593                         continue;
 594                 crash_base = (chunk->addr + chunk->size) - crash_size;
 595                 if (crash_base < crash_size)
 596                         continue;
 597                 if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
 598                         continue;
 599                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 600                         continue;
 601                 return crash_base;
 602         }
 603         *msg = "no suitable area found";
 604         return 0;
 605 }
 606
 607 /*
 608  * Check if crash_base and crash_size is valid
 609  */
 610 static int __init verify_crash_base(unsigned long crash_base,
 611                                     unsigned long crash_size,
 612                                     char **msg)
 613 {
 614         struct mem_chunk *chunk;
 615         int i;
 616
 617         /*
 618          * Because we do the swap to zero, we must have at least 'crash_size'
 619          * bytes free space before crash_base
 620          */
 621         if (crash_size > crash_base) {
 622                 *msg = "crashkernel offset must be greater than size";
 623                 return -EINVAL;
 624         }
 625
 626         /* First memory chunk must be at least crash_size */
 627         if (memory_chunk[0].size < crash_size) {
 628                 *msg = "first memory chunk must be at least crashkernel size";
 629                 return -EINVAL;
 630         }
 631         /* Check if we fit into the respective memory chunk */
 632         for (i = 0; i < MEMORY_CHUNKS; i++) {
 633                 chunk = &memory_chunk[i];
 634                 if (chunk->size == 0)
 635                         continue;
 636                 if (crash_base < chunk->addr)
 637                         continue;
 638                 if (crash_base >= chunk->addr + chunk->size)
 639                         continue;
 640                 /* we have found the memory chunk */
 641                 if (crash_base + crash_size > chunk->addr + chunk->size) {
 642                         *msg = "selected memory chunk is too small for "
 643                                 "crashkernel memory";
 644                         return -EINVAL;
 645                 }
 646                 return 0;
 647         }
 648         *msg = "invalid memory range specified";
 649         return -EINVAL;
 650 }
 651
 652 /*
 653  * Reserve kdump memory by creating a memory hole in the mem_chunk array
 654  */
 655 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
 656                                          int type)
 657 {
 658
 659         create_mem_hole(memory_chunk, addr, size, type);
 660 }
 661
 662 /*
 663  * When kdump is enabled, we have to ensure that no memory from
 664  * the area [0 - crashkernel memory size] and
 665  * [crashk_res.start - crashk_res.end] is set offline.
 666  */
 667 static int kdump_mem_notifier(struct notifier_block *nb,
 668                               unsigned long action, void *data)
 669 {
 670         struct memory_notify *arg = data;
 671
 672         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 673                 return NOTIFY_BAD;
 674         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 675                 return NOTIFY_OK;
 676         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 677                 return NOTIFY_OK;
 678         return NOTIFY_BAD;
 679 }
 680
 681 static struct notifier_block kdump_mem_nb = {
 682         .notifier_call = kdump_mem_notifier,
 683 };
 684
 685 #endif
 686
 687 /*
 688  * Make sure that oldmem, where the dump is stored, is protected
 689  */
 690 static void reserve_oldmem(void)
 691 {
 692 #ifdef CONFIG_CRASH_DUMP
 693         if (!OLDMEM_BASE)
 694                 return;
 695
 696         reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
 697         reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
 698                               CHUNK_OLDMEM);
 699         if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
 700                 saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
 701         else
 702                 saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
 703 #endif
 704 }
 705
 706 /*
 707  * Reserve memory for kdump kernel to be loaded with kexec
 708  */
 709 static void __init reserve_crashkernel(void)
 710 {
 711 #ifdef CONFIG_CRASH_DUMP
 712         unsigned long long crash_base, crash_size;
 713         char *msg;
 714         int rc;
 715
 716         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 717                                &crash_base);
 718         if (rc || crash_size == 0)
 719                 return;
 720         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 721         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 722         if (register_memory_notifier(&kdump_mem_nb))
 723                 return;
 724         if (!crash_base)
 725                 crash_base = find_crash_base(crash_size, &msg);
 726         if (!crash_base) {
 727                 pr_info("crashkernel reservation failed: %s\n", msg);
 728                 unregister_memory_notifier(&kdump_mem_nb);
 729                 return;
 730         }
 731         if (verify_crash_base(crash_base, crash_size, &msg)) {
 732                 pr_info("crashkernel reservation failed: %s\n", msg);
 733                 unregister_memory_notifier(&kdump_mem_nb);
 734                 return;
 735         }
 736         if (!OLDMEM_BASE && MACHINE_IS_VM)
 737                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 738         crashk_res.start = crash_base;
 739         crashk_res.end = crash_base + crash_size - 1;
 740         insert_resource(&iomem_resource, &crashk_res);
 741         reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
 742         pr_info("Reserving %lluMB of memory at %lluMB "
 743                 "for crashkernel (System RAM: %luMB)\n",
 744                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
 745 #endif
 746 }
 747
 748 static void __init
 749 setup_memory(void)
 750 {
 751         unsigned long bootmap_size;
 752         unsigned long start_pfn, end_pfn;
 753         int i;
 754
 755         /*
 756          * partially used pages are not usable - thus
 757          * we are rounding upwards:
 758          */
 759         start_pfn = PFN_UP(__pa(&_end));
 760         end_pfn = max_pfn = PFN_DOWN(memory_end);
 761
 762 #ifdef CONFIG_BLK_DEV_INITRD
 763         /*
 764          * Move the initrd in case the bitmap of the bootmem allocater
 765          * would overwrite it.
 766          */
 767
 768         if (INITRD_START && INITRD_SIZE) {
 769                 unsigned long bmap_size;
 770                 unsigned long start;
 771
 772                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 773                 bmap_size = PFN_PHYS(bmap_size);
 774
 775                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 776                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 777
 778 #ifdef CONFIG_CRASH_DUMP
 779                         if (OLDMEM_BASE) {
 780                                 /* Move initrd behind kdump oldmem */
 781                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
 782                                     start < OLDMEM_BASE + OLDMEM_SIZE)
 783                                         start = OLDMEM_BASE + OLDMEM_SIZE;
 784                         }
 785 #endif
 786                         if (start + INITRD_SIZE > memory_end) {
 787                                 pr_err("initrd extends beyond end of "
 788                                        "memory (0x%08lx > 0x%08lx) "
 789                                        "disabling initrd\n",
 790                                        start + INITRD_SIZE, memory_end);
 791                                 INITRD_START = INITRD_SIZE = 0;
 792                         } else {
 793                                 pr_info("Moving initrd (0x%08lx -> "
 794                                         "0x%08lx, size: %ld)\n",
 795                                         INITRD_START, start, INITRD_SIZE);
 796                                 memmove((void *) start, (void *) INITRD_START,
 797                                         INITRD_SIZE);
 798                                 INITRD_START = start;
 799                         }
 800                 }
 801         }
 802 #endif
 803
 804         /*
 805          * Initialize the boot-time allocator
 806          */
 807         bootmap_size = init_bootmem(start_pfn, end_pfn);
 808
 809         /*
 810          * Register RAM areas with the bootmem allocator.
 811          */
 812
 813         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 814                 unsigned long start_chunk, end_chunk, pfn;
 815
 816                 if (memory_chunk[i].type != CHUNK_READ_WRITE &&
 817                     memory_chunk[i].type != CHUNK_CRASHK)
 818                         continue;
 819                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 820                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 821                 end_chunk = min(end_chunk, end_pfn);
 822                 if (start_chunk >= end_chunk)
 823                         continue;
 824                 memblock_add_node(PFN_PHYS(start_chunk),
 825                                   PFN_PHYS(end_chunk - start_chunk), 0);
 826                 pfn = max(start_chunk, start_pfn);
 827                 for (; pfn < end_chunk; pfn++)
 828                         page_set_storage_key(PFN_PHYS(pfn),
 829                                              PAGE_DEFAULT_KEY, 0);
 830         }
 831
 832         psw_set_key(PAGE_DEFAULT_KEY);
 833
 834         free_bootmem_with_active_regions(0, max_pfn);
 835
 836         /*
 837          * Reserve memory used for lowcore/command line/kernel image.
 838          */
 839         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 840         reserve_bootmem((unsigned long)_stext,
 841                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 842                         BOOTMEM_DEFAULT);
 843         /*
 844          * Reserve the bootmem bitmap itself as well. We do this in two
 845          * steps (first step was init_bootmem()) because this catches
 846          * the (very unlikely) case of us accidentally initializing the
 847          * bootmem allocator with an invalid RAM area.
 848          */
 849         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 850                         BOOTMEM_DEFAULT);
 851
 852 #ifdef CONFIG_CRASH_DUMP
 853         if (crashk_res.start)
 854                 reserve_bootmem(crashk_res.start,
 855                                 crashk_res.end - crashk_res.start + 1,
 856                                 BOOTMEM_DEFAULT);
 857         if (is_kdump_kernel())
 858                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
 859                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
 860 #endif
 861 #ifdef CONFIG_BLK_DEV_INITRD
 862         if (INITRD_START && INITRD_SIZE) {
 863                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 864                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 865                                         BOOTMEM_DEFAULT);
 866                         initrd_start = INITRD_START;
 867                         initrd_end = initrd_start + INITRD_SIZE;
 868                 } else {
 869                         pr_err("initrd extends beyond end of "
 870                                "memory (0x%08lx > 0x%08lx) "
 871                                "disabling initrd\n",
 872                                initrd_start + INITRD_SIZE, memory_end);
 873                         initrd_start = initrd_end = 0;
 874                 }
 875         }
 876 #endif
 877 }
 878
 879 /*
 880  * Setup hardware capabilities.
 881  */
 882 static void __init setup_hwcaps(void)
 883 {
 884         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 885         struct cpuid cpu_id;
 886         int i;
 887
 888         /*
 889          * The store facility list bits numbers as found in the principles
 890          * of operation are numbered with bit 1UL<<31 as number 0 to
 891          * bit 1UL<<0 as number 31.
 892          *   Bit 0: instructions named N3, "backported" to esa-mode
 893          *   Bit 2: z/Architecture mode is active
 894          *   Bit 7: the store-facility-list-extended facility is installed
 895          *   Bit 17: the message-security assist is installed
 896          *   Bit 19: the long-displacement facility is installed
 897          *   Bit 21: the extended-immediate facility is installed
 898          *   Bit 22: extended-translation facility 3 is installed
 899          *   Bit 30: extended-translation facility 3 enhancement facility
 900          * These get translated to:
 901          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 902          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 903          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 904          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 905          */
 906         for (i = 0; i < 6; i++)
 907                 if (test_facility(stfl_bits[i]))
 908                         elf_hwcap |= 1UL << i;
 909
 910         if (test_facility(22) && test_facility(30))
 911                 elf_hwcap |= HWCAP_S390_ETF3EH;
 912
 913         /*
 914          * Check for additional facilities with store-facility-list-extended.
 915          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 916          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 917          * as stored by stfl, bits 32-xxx contain additional facilities.
 918          * How many facility words are stored depends on the number of
 919          * doublewords passed to the instruction. The additional facilities
 920          * are:
 921          *   Bit 42: decimal floating point facility is installed
 922          *   Bit 44: perform floating point operation facility is installed
 923          * translated to:
 924          *   HWCAP_S390_DFP bit 6 (42 && 44).
 925          */
 926         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 927                 elf_hwcap |= HWCAP_S390_DFP;
 928
 929         /*
 930          * Huge page support HWCAP_S390_HPAGE is bit 7.
 931          */
 932         if (MACHINE_HAS_HPAGE)
 933                 elf_hwcap |= HWCAP_S390_HPAGE;
 934
 935         /*
 936          * 64-bit register support for 31-bit processes
 937          * HWCAP_S390_HIGH_GPRS is bit 9.
 938          */
 939         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 940
 941         get_cpu_id(&cpu_id);
 942         switch (cpu_id.machine) {
 943         case 0x9672:
 944 #if !defined(CONFIG_64BIT)
 945         default:        /* Use "g5" as default for 31 bit kernels. */
 946 #endif
 947                 strcpy(elf_platform, "g5");
 948                 break;
 949         case 0x2064:
 950         case 0x2066:
 951 #if defined(CONFIG_64BIT)
 952         default:        /* Use "z900" as default for 64 bit kernels. */
 953 #endif
 954                 strcpy(elf_platform, "z900");
 955                 break;
 956         case 0x2084:
 957         case 0x2086:
 958                 strcpy(elf_platform, "z990");
 959                 break;
 960         case 0x2094:
 961         case 0x2096:
 962                 strcpy(elf_platform, "z9-109");
 963                 break;
 964         case 0x2097:
 965         case 0x2098:
 966                 strcpy(elf_platform, "z10");
 967                 break;
 968         case 0x2817:
 969         case 0x2818:
 970                 strcpy(elf_platform, "z196");
 971                 break;
 972         }
 973 }
 974
 975 /*
 976  * Setup function called from init/main.c just after the banner
 977  * was printed.
 978  */
 979
 980 void __init
 981 setup_arch(char **cmdline_p)
 982 {
 983         /*
 984          * print what head.S has found out about the machine
 985          */
 986 #ifndef CONFIG_64BIT
 987         if (MACHINE_IS_VM)
 988                 pr_info("Linux is running as a z/VM "
 989                         "guest operating system in 31-bit mode\n");
 990         else if (MACHINE_IS_LPAR)
 991                 pr_info("Linux is running natively in 31-bit mode\n");
 992         if (MACHINE_HAS_IEEE)
 993                 pr_info("The hardware system has IEEE compatible "
 994                         "floating point units\n");
 995         else
 996                 pr_info("The hardware system has no IEEE compatible "
 997                         "floating point units\n");
 998 #else /* CONFIG_64BIT */
 999         if (MACHINE_IS_VM)
1000                 pr_info("Linux is running as a z/VM "
1001                         "guest operating system in 64-bit mode\n");
1002         else if (MACHINE_IS_KVM)
1003                 pr_info("Linux is running under KVM in 64-bit mode\n");
1004         else if (MACHINE_IS_LPAR)
1005                 pr_info("Linux is running natively in 64-bit mode\n");
1006 #endif /* CONFIG_64BIT */
1007
1008         /* Have one command line that is parsed and saved in /proc/cmdline */
1009         /* boot_command_line has been already set up in early.c */
1010         *cmdline_p = boot_command_line;
1011
1012         ROOT_DEV = Root_RAM0;
1013
1014         init_mm.start_code = PAGE_OFFSET;
1015         init_mm.end_code = (unsigned long) &_etext;
1016         init_mm.end_data = (unsigned long) &_edata;
1017         init_mm.brk = (unsigned long) &_end;
1018
1019         if (MACHINE_HAS_MVCOS)
1020                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1021         else
1022                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1023
1024         parse_early_param();
1025
1026         setup_ipl();
1027         setup_memory_end();
1028         setup_addressing_mode();
1029         reserve_oldmem();
1030         reserve_crashkernel();
1031         setup_memory();
1032         setup_resources();
1033         setup_vmcoreinfo();
1034         setup_restart_psw();
1035         setup_lowcore();
1036
1037         cpu_init();
1038         s390_init_cpu_topology();
1039
1040         /*
1041          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1042          */
1043         setup_hwcaps();
1044
1045         /*
1046          * Create kernel page tables and switch to virtual addressing.
1047          */
1048         paging_init();
1049
1050         /* Setup default console */
1051         conmode_default();
1052         set_preferred_console();
1053
1054         /* Setup zfcpdump support */
1055         setup_zfcpdump(console_devno);
1056 }