arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "arch/i386/kernel/setup.c"
  10  *    Copyright (C) 1995, Linus Torvalds
  11  */
  12
  13 /*
  14  * This file handles the architecture-dependent parts of initialization
  15  */
  16
  17 #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/slab.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
  47 #include <asm/ipl.h>
  48 #include <asm/uaccess.h>
  49 #include <asm/system.h>
  50 #include <asm/smp.h>
  51 #include <asm/mmu_context.h>
  52 #include <asm/cpcmd.h>
  53 #include <asm/lowcore.h>
  54 #include <asm/irq.h>
  55 #include <asm/page.h>
  56 #include <asm/ptrace.h>
  57 #include <asm/sections.h>
  58 #include <asm/ebcdic.h>
  59 #include <asm/compat.h>
  60 #include <asm/kvm_virtio.h>
  61
  62 long psw_kernel_bits    = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
  63                            PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
  64 long psw_user_bits      = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
  65                            PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
  66                            PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
  67
  68 /*
  69  * User copy operations.
  70  */
  71 struct uaccess_ops uaccess;
  72 EXPORT_SYMBOL(uaccess);
  73
  74 /*
  75  * Machine setup..
  76  */
  77 unsigned int console_mode = 0;
  78 EXPORT_SYMBOL(console_mode);
  79
  80 unsigned int console_devno = -1;
  81 EXPORT_SYMBOL(console_devno);
  82
  83 unsigned int console_irq = -1;
  84 EXPORT_SYMBOL(console_irq);
  85
  86 unsigned long elf_hwcap = 0;
  87 char elf_platform[ELF_PLATFORM_SIZE];
  88
  89 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  90 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
  91
  92 int __initdata memory_end_set;
  93 unsigned long __initdata memory_end;
  94
  95 /* An array with a pointer to the lowcore of every CPU. */
  96 struct _lowcore *lowcore_ptr[NR_CPUS];
  97 EXPORT_SYMBOL(lowcore_ptr);
  98
  99 /*
 100  * This is set up by the setup-routine at boot-time
 101  * for S390 need to find out, what we have to setup
 102  * using address 0x10400 ...
 103  */
 104
 105 #include <asm/setup.h>
 106
 107 static struct resource code_resource = {
 108         .name  = "Kernel code",
 109         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 110 };
 111
 112 static struct resource data_resource = {
 113         .name = "Kernel data",
 114         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 115 };
 116
 117 /*
 118  * cpu_init() initializes state that is per-CPU.
 119  */
 120 void __cpuinit cpu_init(void)
 121 {
 122         /*
 123          * Store processor id in lowcore (used e.g. in timer_interrupt)
 124          */
 125         get_cpu_id(&S390_lowcore.cpu_id);
 126
 127         /*
 128          * Force FPU initialization:
 129          */
 130         clear_thread_flag(TIF_USEDFPU);
 131         clear_used_math();
 132
 133         atomic_inc(&init_mm.mm_count);
 134         current->active_mm = &init_mm;
 135         BUG_ON(current->mm);
 136         enter_lazy_tlb(&init_mm, current);
 137 }
 138
 139 /*
 140  * condev= and conmode= setup parameter.
 141  */
 142
 143 static int __init condev_setup(char *str)
 144 {
 145         int vdev;
 146
 147         vdev = simple_strtoul(str, &str, 0);
 148         if (vdev >= 0 && vdev < 65536) {
 149                 console_devno = vdev;
 150                 console_irq = -1;
 151         }
 152         return 1;
 153 }
 154
 155 __setup("condev=", condev_setup);
 156
 157 static int __init conmode_setup(char *str)
 158 {
 159 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 160         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 161                 SET_CONSOLE_SCLP;
 162 #endif
 163 #if defined(CONFIG_TN3215_CONSOLE)
 164         if (strncmp(str, "3215", 5) == 0)
 165                 SET_CONSOLE_3215;
 166 #endif
 167 #if defined(CONFIG_TN3270_CONSOLE)
 168         if (strncmp(str, "3270", 5) == 0)
 169                 SET_CONSOLE_3270;
 170 #endif
 171         return 1;
 172 }
 173
 174 __setup("conmode=", conmode_setup);
 175
 176 static void __init conmode_default(void)
 177 {
 178         char query_buffer[1024];
 179         char *ptr;
 180
 181         if (MACHINE_IS_VM) {
 182                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 183                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 184                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 185                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 186                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 187                 ptr = strstr(query_buffer, "CONMODE");
 188                 /*
 189                  * Set the conmode to 3215 so that the device recognition
 190                  * will set the cu_type of the console to 3215. If the
 191                  * conmode is 3270 and we don't set it back then both
 192                  * 3215 and the 3270 driver will try to access the console
 193                  * device (3215 as console and 3270 as normal tty).
 194                  */
 195                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 196                 if (ptr == NULL) {
 197 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 198                         SET_CONSOLE_SCLP;
 199 #endif
 200                         return;
 201                 }
 202                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 203 #if defined(CONFIG_TN3270_CONSOLE)
 204                         SET_CONSOLE_3270;
 205 #elif defined(CONFIG_TN3215_CONSOLE)
 206                         SET_CONSOLE_3215;
 207 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 208                         SET_CONSOLE_SCLP;
 209 #endif
 210                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 211 #if defined(CONFIG_TN3215_CONSOLE)
 212                         SET_CONSOLE_3215;
 213 #elif defined(CONFIG_TN3270_CONSOLE)
 214                         SET_CONSOLE_3270;
 215 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 216                         SET_CONSOLE_SCLP;
 217 #endif
 218                 }
 219         } else {
 220 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 221                 SET_CONSOLE_SCLP;
 222 #endif
 223         }
 224 }
 225
 226 #ifdef CONFIG_ZFCPDUMP
 227 static void __init setup_zfcpdump(unsigned int console_devno)
 228 {
 229         static char str[41];
 230
 231         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 232                 return;
 233         if (console_devno != -1)
 234                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 235                         ipl_info.data.fcp.dev_id.devno, console_devno);
 236         else
 237                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 238                         ipl_info.data.fcp.dev_id.devno);
 239         strcat(boot_command_line, str);
 240         console_loglevel = 2;
 241 }
 242 #else
 243 static inline void setup_zfcpdump(unsigned int console_devno) {}
 244 #endif /* CONFIG_ZFCPDUMP */
 245
 246  /*
 247  * Reboot, halt and power_off stubs. They just call _machine_restart,
 248  * _machine_halt or _machine_power_off.
 249  */
 250
 251 void machine_restart(char *command)
 252 {
 253         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 254                 /*
 255                  * Only unblank the console if we are called in enabled
 256                  * context or a bust_spinlocks cleared the way for us.
 257                  */
 258                 console_unblank();
 259         _machine_restart(command);
 260 }
 261
 262 void machine_halt(void)
 263 {
 264         if (!in_interrupt() || oops_in_progress)
 265                 /*
 266                  * Only unblank the console if we are called in enabled
 267                  * context or a bust_spinlocks cleared the way for us.
 268                  */
 269                 console_unblank();
 270         _machine_halt();
 271 }
 272
 273 void machine_power_off(void)
 274 {
 275         if (!in_interrupt() || oops_in_progress)
 276                 /*
 277                  * Only unblank the console if we are called in enabled
 278                  * context or a bust_spinlocks cleared the way for us.
 279                  */
 280                 console_unblank();
 281         _machine_power_off();
 282 }
 283
 284 /*
 285  * Dummy power off function.
 286  */
 287 void (*pm_power_off)(void) = machine_power_off;
 288
 289 static int __init early_parse_mem(char *p)
 290 {
 291         memory_end = memparse(p, &p);
 292         memory_end_set = 1;
 293         return 0;
 294 }
 295 early_param("mem", early_parse_mem);
 296
 297 #ifdef CONFIG_S390_SWITCH_AMODE
 298 unsigned int switch_amode = 0;
 299 EXPORT_SYMBOL_GPL(switch_amode);
 300
 301 static int set_amode_and_uaccess(unsigned long user_amode,
 302                                  unsigned long user32_amode)
 303 {
 304         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 305                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 306                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 307 #ifdef CONFIG_COMPAT
 308         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 309                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 310                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 311         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 312                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 313                           PSW32_MASK_PSTATE;
 314 #endif
 315         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 316                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 317
 318         if (MACHINE_HAS_MVCOS) {
 319                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 320                 return 1;
 321         } else {
 322                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 323                 return 0;
 324         }
 325 }
 326
 327 /*
 328  * Switch kernel/user addressing modes?
 329  */
 330 static int __init early_parse_switch_amode(char *p)
 331 {
 332         switch_amode = 1;
 333         return 0;
 334 }
 335 early_param("switch_amode", early_parse_switch_amode);
 336
 337 #else /* CONFIG_S390_SWITCH_AMODE */
 338 static inline int set_amode_and_uaccess(unsigned long user_amode,
 339                                         unsigned long user32_amode)
 340 {
 341         return 0;
 342 }
 343 #endif /* CONFIG_S390_SWITCH_AMODE */
 344
 345 #ifdef CONFIG_S390_EXEC_PROTECT
 346 unsigned int s390_noexec = 0;
 347 EXPORT_SYMBOL_GPL(s390_noexec);
 348
 349 /*
 350  * Enable execute protection?
 351  */
 352 static int __init early_parse_noexec(char *p)
 353 {
 354         if (!strncmp(p, "off", 3))
 355                 return 0;
 356         switch_amode = 1;
 357         s390_noexec = 1;
 358         return 0;
 359 }
 360 early_param("noexec", early_parse_noexec);
 361 #endif /* CONFIG_S390_EXEC_PROTECT */
 362
 363 static void setup_addressing_mode(void)
 364 {
 365         if (s390_noexec) {
 366                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
 367                                           PSW32_ASC_SECONDARY))
 368                         pr_info("Execute protection active, "
 369                                 "mvcos available\n");
 370                 else
 371                         pr_info("Execute protection active, "
 372                                 "mvcos not available\n");
 373         } else if (switch_amode) {
 374                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 375                         pr_info("Address spaces switched, "
 376                                 "mvcos available\n");
 377                 else
 378                         pr_info("Address spaces switched, "
 379                                 "mvcos not available\n");
 380         }
 381 #ifdef CONFIG_TRACE_IRQFLAGS
 382         sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 383         io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 384 #endif
 385 }
 386
 387 static void __init
 388 setup_lowcore(void)
 389 {
 390         struct _lowcore *lc;
 391         int lc_pages;
 392
 393         /*
 394          * Setup lowcore for boot cpu
 395          */
 396         lc_pages = sizeof(void *) == 8 ? 2 : 1;
 397         lc = (struct _lowcore *)
 398                 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
 399         memset(lc, 0, lc_pages * PAGE_SIZE);
 400         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 401         lc->restart_psw.addr =
 402                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 403         if (switch_amode)
 404                 lc->restart_psw.mask |= PSW_ASC_HOME;
 405         lc->external_new_psw.mask = psw_kernel_bits;
 406         lc->external_new_psw.addr =
 407                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 408         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 409         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 410         lc->program_new_psw.mask = psw_kernel_bits;
 411         lc->program_new_psw.addr =
 412                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 413         lc->mcck_new_psw.mask =
 414                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 415         lc->mcck_new_psw.addr =
 416                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 417         lc->io_new_psw.mask = psw_kernel_bits;
 418         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 419         lc->clock_comparator = -1ULL;
 420         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 421         lc->async_stack = (unsigned long)
 422                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 423         lc->panic_stack = (unsigned long)
 424                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 425         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 426         lc->thread_info = (unsigned long) &init_thread_union;
 427         lc->machine_flags = S390_lowcore.machine_flags;
 428 #ifndef CONFIG_64BIT
 429         if (MACHINE_HAS_IEEE) {
 430                 lc->extended_save_area_addr = (__u32)
 431                         __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
 432                 /* enable extended save area */
 433                 __ctl_set_bit(14, 29);
 434         }
 435 #else
 436         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 437 #endif
 438         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 439         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 440         lc->exit_timer = S390_lowcore.exit_timer;
 441         lc->user_timer = S390_lowcore.user_timer;
 442         lc->system_timer = S390_lowcore.system_timer;
 443         lc->steal_timer = S390_lowcore.steal_timer;
 444         lc->last_update_timer = S390_lowcore.last_update_timer;
 445         lc->last_update_clock = S390_lowcore.last_update_clock;
 446         lc->ftrace_func = S390_lowcore.ftrace_func;
 447         set_prefix((u32)(unsigned long) lc);
 448         lowcore_ptr[0] = lc;
 449 }
 450
 451 static void __init
 452 setup_resources(void)
 453 {
 454         struct resource *res, *sub_res;
 455         int i;
 456
 457         code_resource.start = (unsigned long) &_text;
 458         code_resource.end = (unsigned long) &_etext - 1;
 459         data_resource.start = (unsigned long) &_etext;
 460         data_resource.end = (unsigned long) &_edata - 1;
 461
 462         for (i = 0; i < MEMORY_CHUNKS; i++) {
 463                 if (!memory_chunk[i].size)
 464                         continue;
 465                 res = alloc_bootmem_low(sizeof(struct resource));
 466                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 467                 switch (memory_chunk[i].type) {
 468                 case CHUNK_READ_WRITE:
 469                         res->name = "System RAM";
 470                         break;
 471                 case CHUNK_READ_ONLY:
 472                         res->name = "System ROM";
 473                         res->flags |= IORESOURCE_READONLY;
 474                         break;
 475                 default:
 476                         res->name = "reserved";
 477                 }
 478                 res->start = memory_chunk[i].addr;
 479                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
 480                 request_resource(&iomem_resource, res);
 481
 482                 if (code_resource.start >= res->start  &&
 483                         code_resource.start <= res->end &&
 484                         code_resource.end > res->end) {
 485                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 486                         memcpy(sub_res, &code_resource,
 487                                 sizeof(struct resource));
 488                         sub_res->end = res->end;
 489                         code_resource.start = res->end + 1;
 490                         request_resource(res, sub_res);
 491                 }
 492
 493                 if (code_resource.start >= res->start &&
 494                         code_resource.start <= res->end &&
 495                         code_resource.end <= res->end)
 496                         request_resource(res, &code_resource);
 497
 498                 if (data_resource.start >= res->start &&
 499                         data_resource.start <= res->end &&
 500                         data_resource.end > res->end) {
 501                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 502                         memcpy(sub_res, &data_resource,
 503                                 sizeof(struct resource));
 504                         sub_res->end = res->end;
 505                         data_resource.start = res->end + 1;
 506                         request_resource(res, sub_res);
 507                 }
 508
 509                 if (data_resource.start >= res->start &&
 510                         data_resource.start <= res->end &&
 511                         data_resource.end <= res->end)
 512                         request_resource(res, &data_resource);
 513         }
 514 }
 515
 516 unsigned long real_memory_size;
 517 EXPORT_SYMBOL_GPL(real_memory_size);
 518
 519 static void __init setup_memory_end(void)
 520 {
 521         unsigned long memory_size;
 522         unsigned long max_mem;
 523         int i;
 524
 525 #ifdef CONFIG_ZFCPDUMP
 526         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
 527                 memory_end = ZFCPDUMP_HSA_SIZE;
 528                 memory_end_set = 1;
 529         }
 530 #endif
 531         memory_size = 0;
 532         memory_end &= PAGE_MASK;
 533
 534         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 535         memory_end = min(max_mem, memory_end);
 536
 537         /*
 538          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 539          * extra checks that HOLES_IN_ZONE would require.
 540          */
 541         for (i = 0; i < MEMORY_CHUNKS; i++) {
 542                 unsigned long start, end;
 543                 struct mem_chunk *chunk;
 544                 unsigned long align;
 545
 546                 chunk = &memory_chunk[i];
 547                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 548                 start = (chunk->addr + align - 1) & ~(align - 1);
 549                 end = (chunk->addr + chunk->size) & ~(align - 1);
 550                 if (start >= end)
 551                         memset(chunk, 0, sizeof(*chunk));
 552                 else {
 553                         chunk->addr = start;
 554                         chunk->size = end - start;
 555                 }
 556         }
 557
 558         for (i = 0; i < MEMORY_CHUNKS; i++) {
 559                 struct mem_chunk *chunk = &memory_chunk[i];
 560
 561                 real_memory_size = max(real_memory_size,
 562                                        chunk->addr + chunk->size);
 563                 if (chunk->addr >= max_mem) {
 564                         memset(chunk, 0, sizeof(*chunk));
 565                         continue;
 566                 }
 567                 if (chunk->addr + chunk->size > max_mem)
 568                         chunk->size = max_mem - chunk->addr;
 569                 memory_size = max(memory_size, chunk->addr + chunk->size);
 570         }
 571         if (!memory_end)
 572                 memory_end = memory_size;
 573 }
 574
 575 static void __init
 576 setup_memory(void)
 577 {
 578         unsigned long bootmap_size;
 579         unsigned long start_pfn, end_pfn;
 580         int i;
 581
 582         /*
 583          * partially used pages are not usable - thus
 584          * we are rounding upwards:
 585          */
 586         start_pfn = PFN_UP(__pa(&_end));
 587         end_pfn = max_pfn = PFN_DOWN(memory_end);
 588
 589 #ifdef CONFIG_BLK_DEV_INITRD
 590         /*
 591          * Move the initrd in case the bitmap of the bootmem allocater
 592          * would overwrite it.
 593          */
 594
 595         if (INITRD_START && INITRD_SIZE) {
 596                 unsigned long bmap_size;
 597                 unsigned long start;
 598
 599                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 600                 bmap_size = PFN_PHYS(bmap_size);
 601
 602                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 603                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 604
 605                         if (start + INITRD_SIZE > memory_end) {
 606                                 pr_err("initrd extends beyond end of "
 607                                        "memory (0x%08lx > 0x%08lx) "
 608                                        "disabling initrd\n",
 609                                        start + INITRD_SIZE, memory_end);
 610                                 INITRD_START = INITRD_SIZE = 0;
 611                         } else {
 612                                 pr_info("Moving initrd (0x%08lx -> "
 613                                         "0x%08lx, size: %ld)\n",
 614                                         INITRD_START, start, INITRD_SIZE);
 615                                 memmove((void *) start, (void *) INITRD_START,
 616                                         INITRD_SIZE);
 617                                 INITRD_START = start;
 618                         }
 619                 }
 620         }
 621 #endif
 622
 623         /*
 624          * Initialize the boot-time allocator
 625          */
 626         bootmap_size = init_bootmem(start_pfn, end_pfn);
 627
 628         /*
 629          * Register RAM areas with the bootmem allocator.
 630          */
 631
 632         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 633                 unsigned long start_chunk, end_chunk, pfn;
 634
 635                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 636                         continue;
 637                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 638                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 639                 end_chunk = min(end_chunk, end_pfn);
 640                 if (start_chunk >= end_chunk)
 641                         continue;
 642                 add_active_range(0, start_chunk, end_chunk);
 643                 pfn = max(start_chunk, start_pfn);
 644                 for (; pfn < end_chunk; pfn++)
 645                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
 646         }
 647
 648         psw_set_key(PAGE_DEFAULT_KEY);
 649
 650         free_bootmem_with_active_regions(0, max_pfn);
 651
 652         /*
 653          * Reserve memory used for lowcore/command line/kernel image.
 654          */
 655         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 656         reserve_bootmem((unsigned long)_stext,
 657                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 658                         BOOTMEM_DEFAULT);
 659         /*
 660          * Reserve the bootmem bitmap itself as well. We do this in two
 661          * steps (first step was init_bootmem()) because this catches
 662          * the (very unlikely) case of us accidentally initializing the
 663          * bootmem allocator with an invalid RAM area.
 664          */
 665         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 666                         BOOTMEM_DEFAULT);
 667
 668 #ifdef CONFIG_BLK_DEV_INITRD
 669         if (INITRD_START && INITRD_SIZE) {
 670                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 671                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 672                                         BOOTMEM_DEFAULT);
 673                         initrd_start = INITRD_START;
 674                         initrd_end = initrd_start + INITRD_SIZE;
 675                 } else {
 676                         pr_err("initrd extends beyond end of "
 677                                "memory (0x%08lx > 0x%08lx) "
 678                                "disabling initrd\n",
 679                                initrd_start + INITRD_SIZE, memory_end);
 680                         initrd_start = initrd_end = 0;
 681                 }
 682         }
 683 #endif
 684 }
 685
 686 /*
 687  * Setup hardware capabilities.
 688  */
 689 static void __init setup_hwcaps(void)
 690 {
 691         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 692         unsigned long long facility_list_extended;
 693         unsigned int facility_list;
 694         int i;
 695
 696         facility_list = stfl();
 697         /*
 698          * The store facility list bits numbers as found in the principles
 699          * of operation are numbered with bit 1UL<<31 as number 0 to
 700          * bit 1UL<<0 as number 31.
 701          *   Bit 0: instructions named N3, "backported" to esa-mode
 702          *   Bit 2: z/Architecture mode is active
 703          *   Bit 7: the store-facility-list-extended facility is installed
 704          *   Bit 17: the message-security assist is installed
 705          *   Bit 19: the long-displacement facility is installed
 706          *   Bit 21: the extended-immediate facility is installed
 707          *   Bit 22: extended-translation facility 3 is installed
 708          *   Bit 30: extended-translation facility 3 enhancement facility
 709          * These get translated to:
 710          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 711          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 712          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 713          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 714          */
 715         for (i = 0; i < 6; i++)
 716                 if (facility_list & (1UL << (31 - stfl_bits[i])))
 717                         elf_hwcap |= 1UL << i;
 718
 719         if ((facility_list & (1UL << (31 - 22)))
 720             && (facility_list & (1UL << (31 - 30))))
 721                 elf_hwcap |= 1UL << 8;
 722
 723         /*
 724          * Check for additional facilities with store-facility-list-extended.
 725          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 726          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 727          * as stored by stfl, bits 32-xxx contain additional facilities.
 728          * How many facility words are stored depends on the number of
 729          * doublewords passed to the instruction. The additional facilites
 730          * are:
 731          *   Bit 42: decimal floating point facility is installed
 732          *   Bit 44: perform floating point operation facility is installed
 733          * translated to:
 734          *   HWCAP_S390_DFP bit 6 (42 && 44).
 735          */
 736         if ((elf_hwcap & (1UL << 2)) &&
 737             __stfle(&facility_list_extended, 1) > 0) {
 738                 if ((facility_list_extended & (1ULL << (63 - 42)))
 739                     && (facility_list_extended & (1ULL << (63 - 44))))
 740                         elf_hwcap |= 1UL << 6;
 741         }
 742
 743         if (MACHINE_HAS_HPAGE)
 744                 elf_hwcap |= 1UL << 7;
 745
 746         switch (S390_lowcore.cpu_id.machine) {
 747         case 0x9672:
 748 #if !defined(CONFIG_64BIT)
 749         default:        /* Use "g5" as default for 31 bit kernels. */
 750 #endif
 751                 strcpy(elf_platform, "g5");
 752                 break;
 753         case 0x2064:
 754         case 0x2066:
 755 #if defined(CONFIG_64BIT)
 756         default:        /* Use "z900" as default for 64 bit kernels. */
 757 #endif
 758                 strcpy(elf_platform, "z900");
 759                 break;
 760         case 0x2084:
 761         case 0x2086:
 762                 strcpy(elf_platform, "z990");
 763                 break;
 764         case 0x2094:
 765         case 0x2096:
 766                 strcpy(elf_platform, "z9-109");
 767                 break;
 768         case 0x2097:
 769         case 0x2098:
 770                 strcpy(elf_platform, "z10");
 771                 break;
 772         }
 773 }
 774
 775 /*
 776  * Setup function called from init/main.c just after the banner
 777  * was printed.
 778  */
 779
 780 void __init
 781 setup_arch(char **cmdline_p)
 782 {
 783         /* set up preferred console */
 784         add_preferred_console("ttyS", 0, NULL);
 785
 786         /*
 787          * print what head.S has found out about the machine
 788          */
 789 #ifndef CONFIG_64BIT
 790         if (MACHINE_IS_VM)
 791                 pr_info("Linux is running as a z/VM "
 792                         "guest operating system in 31-bit mode\n");
 793         else
 794                 pr_info("Linux is running natively in 31-bit mode\n");
 795         if (MACHINE_HAS_IEEE)
 796                 pr_info("The hardware system has IEEE compatible "
 797                         "floating point units\n");
 798         else
 799                 pr_info("The hardware system has no IEEE compatible "
 800                         "floating point units\n");
 801 #else /* CONFIG_64BIT */
 802         if (MACHINE_IS_VM)
 803                 pr_info("Linux is running as a z/VM "
 804                         "guest operating system in 64-bit mode\n");
 805         else if (MACHINE_IS_KVM) {
 806                 pr_info("Linux is running under KVM in 64-bit mode\n");
 807                 add_preferred_console("hvc", 0, NULL);
 808                 s390_virtio_console_init();
 809         } else
 810                 pr_info("Linux is running natively in 64-bit mode\n");
 811 #endif /* CONFIG_64BIT */
 812
 813         /* Have one command line that is parsed and saved in /proc/cmdline */
 814         /* boot_command_line has been already set up in early.c */
 815         *cmdline_p = boot_command_line;
 816
 817         ROOT_DEV = Root_RAM0;
 818
 819         init_mm.start_code = PAGE_OFFSET;
 820         init_mm.end_code = (unsigned long) &_etext;
 821         init_mm.end_data = (unsigned long) &_edata;
 822         init_mm.brk = (unsigned long) &_end;
 823
 824         if (MACHINE_HAS_MVCOS)
 825                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
 826         else
 827                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 828
 829         parse_early_param();
 830
 831         setup_ipl();
 832         setup_memory_end();
 833         setup_addressing_mode();
 834         setup_memory();
 835         setup_resources();
 836         setup_lowcore();
 837
 838         cpu_init();
 839         __cpu_logical_map[0] = stap();
 840         s390_init_cpu_topology();
 841
 842         /*
 843          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
 844          */
 845         setup_hwcaps();
 846
 847         /*
 848          * Create kernel page tables and switch to virtual addressing.
 849          */
 850         paging_init();
 851
 852         /* Setup default console */
 853         conmode_default();
 854
 855         /* Setup zfcpdump support */
 856         setup_zfcpdump(console_devno);
 857 }