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