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   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
  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         atomic_inc(&init_mm.mm_count);
 127         current->active_mm = &init_mm;
 128         BUG_ON(current->mm);
 129         enter_lazy_tlb(&init_mm, current);
 130 }
 131
 132 /*
 133  * condev= and conmode= setup parameter.
 134  */
 135
 136 static int __init condev_setup(char *str)
 137 {
 138         int vdev;
 139
 140         vdev = simple_strtoul(str, &str, 0);
 141         if (vdev >= 0 && vdev < 65536) {
 142                 console_devno = vdev;
 143                 console_irq = -1;
 144         }
 145         return 1;
 146 }
 147
 148 __setup("condev=", condev_setup);
 149
 150 static void __init set_preferred_console(void)
 151 {
 152         if (MACHINE_IS_KVM)
 153                 add_preferred_console("hvc", 0, NULL);
 154         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 155                 add_preferred_console("ttyS", 0, NULL);
 156         else if (CONSOLE_IS_3270)
 157                 add_preferred_console("tty3270", 0, NULL);
 158 }
 159
 160 static int __init conmode_setup(char *str)
 161 {
 162 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 163         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 164                 SET_CONSOLE_SCLP;
 165 #endif
 166 #if defined(CONFIG_TN3215_CONSOLE)
 167         if (strncmp(str, "3215", 5) == 0)
 168                 SET_CONSOLE_3215;
 169 #endif
 170 #if defined(CONFIG_TN3270_CONSOLE)
 171         if (strncmp(str, "3270", 5) == 0)
 172                 SET_CONSOLE_3270;
 173 #endif
 174         set_preferred_console();
 175         return 1;
 176 }
 177
 178 __setup("conmode=", conmode_setup);
 179
 180 static void __init conmode_default(void)
 181 {
 182         char query_buffer[1024];
 183         char *ptr;
 184
 185         if (MACHINE_IS_VM) {
 186                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 187                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 188                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 189                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 190                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 191                 ptr = strstr(query_buffer, "CONMODE");
 192                 /*
 193                  * Set the conmode to 3215 so that the device recognition
 194                  * will set the cu_type of the console to 3215. If the
 195                  * conmode is 3270 and we don't set it back then both
 196                  * 3215 and the 3270 driver will try to access the console
 197                  * device (3215 as console and 3270 as normal tty).
 198                  */
 199                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 200                 if (ptr == NULL) {
 201 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 202                         SET_CONSOLE_SCLP;
 203 #endif
 204                         return;
 205                 }
 206                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 207 #if defined(CONFIG_TN3270_CONSOLE)
 208                         SET_CONSOLE_3270;
 209 #elif defined(CONFIG_TN3215_CONSOLE)
 210                         SET_CONSOLE_3215;
 211 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 212                         SET_CONSOLE_SCLP;
 213 #endif
 214                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 215 #if defined(CONFIG_TN3215_CONSOLE)
 216                         SET_CONSOLE_3215;
 217 #elif defined(CONFIG_TN3270_CONSOLE)
 218                         SET_CONSOLE_3270;
 219 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 220                         SET_CONSOLE_SCLP;
 221 #endif
 222                 }
 223         } else {
 224 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 225                 SET_CONSOLE_SCLP;
 226 #endif
 227         }
 228 }
 229
 230 #ifdef CONFIG_ZFCPDUMP
 231 static void __init setup_zfcpdump(unsigned int console_devno)
 232 {
 233         static char str[41];
 234
 235         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 236                 return;
 237         if (console_devno != -1)
 238                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 239                         ipl_info.data.fcp.dev_id.devno, console_devno);
 240         else
 241                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 242                         ipl_info.data.fcp.dev_id.devno);
 243         strcat(boot_command_line, str);
 244         console_loglevel = 2;
 245 }
 246 #else
 247 static inline void setup_zfcpdump(unsigned int console_devno) {}
 248 #endif /* CONFIG_ZFCPDUMP */
 249
 250  /*
 251  * Reboot, halt and power_off stubs. They just call _machine_restart,
 252  * _machine_halt or _machine_power_off.
 253  */
 254
 255 void machine_restart(char *command)
 256 {
 257         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 258                 /*
 259                  * Only unblank the console if we are called in enabled
 260                  * context or a bust_spinlocks cleared the way for us.
 261                  */
 262                 console_unblank();
 263         _machine_restart(command);
 264 }
 265
 266 void machine_halt(void)
 267 {
 268         if (!in_interrupt() || oops_in_progress)
 269                 /*
 270                  * Only unblank the console if we are called in enabled
 271                  * context or a bust_spinlocks cleared the way for us.
 272                  */
 273                 console_unblank();
 274         _machine_halt();
 275 }
 276
 277 void machine_power_off(void)
 278 {
 279         if (!in_interrupt() || oops_in_progress)
 280                 /*
 281                  * Only unblank the console if we are called in enabled
 282                  * context or a bust_spinlocks cleared the way for us.
 283                  */
 284                 console_unblank();
 285         _machine_power_off();
 286 }
 287
 288 /*
 289  * Dummy power off function.
 290  */
 291 void (*pm_power_off)(void) = machine_power_off;
 292
 293 static int __init early_parse_mem(char *p)
 294 {
 295         memory_end = memparse(p, &p);
 296         memory_end_set = 1;
 297         return 0;
 298 }
 299 early_param("mem", early_parse_mem);
 300
 301 unsigned int user_mode = HOME_SPACE_MODE;
 302 EXPORT_SYMBOL_GPL(user_mode);
 303
 304 static int set_amode_and_uaccess(unsigned long user_amode,
 305                                  unsigned long user32_amode)
 306 {
 307         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 308                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 309                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 310 #ifdef CONFIG_COMPAT
 311         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 312                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 313                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 314         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 315                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 316                           PSW32_MASK_PSTATE;
 317 #endif
 318         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 319                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 320
 321         if (MACHINE_HAS_MVCOS) {
 322                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 323                 return 1;
 324         } else {
 325                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 326                 return 0;
 327         }
 328 }
 329
 330 /*
 331  * Switch kernel/user addressing modes?
 332  */
 333 static int __init early_parse_switch_amode(char *p)
 334 {
 335         if (user_mode != SECONDARY_SPACE_MODE)
 336                 user_mode = PRIMARY_SPACE_MODE;
 337         return 0;
 338 }
 339 early_param("switch_amode", early_parse_switch_amode);
 340
 341 static int __init early_parse_user_mode(char *p)
 342 {
 343         if (p && strcmp(p, "primary") == 0)
 344                 user_mode = PRIMARY_SPACE_MODE;
 345 #ifdef CONFIG_S390_EXEC_PROTECT
 346         else if (p && strcmp(p, "secondary") == 0)
 347                 user_mode = SECONDARY_SPACE_MODE;
 348 #endif
 349         else if (!p || strcmp(p, "home") == 0)
 350                 user_mode = HOME_SPACE_MODE;
 351         else
 352                 return 1;
 353         return 0;
 354 }
 355 early_param("user_mode", early_parse_user_mode);
 356
 357 #ifdef CONFIG_S390_EXEC_PROTECT
 358 /*
 359  * Enable execute protection?
 360  */
 361 static int __init early_parse_noexec(char *p)
 362 {
 363         if (!strncmp(p, "off", 3))
 364                 return 0;
 365         user_mode = SECONDARY_SPACE_MODE;
 366         return 0;
 367 }
 368 early_param("noexec", early_parse_noexec);
 369 #endif /* CONFIG_S390_EXEC_PROTECT */
 370
 371 static void setup_addressing_mode(void)
 372 {
 373         if (user_mode == SECONDARY_SPACE_MODE) {
 374                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
 375                                           PSW32_ASC_SECONDARY))
 376                         pr_info("Execute protection active, "
 377                                 "mvcos available\n");
 378                 else
 379                         pr_info("Execute protection active, "
 380                                 "mvcos not available\n");
 381         } else if (user_mode == PRIMARY_SPACE_MODE) {
 382                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 383                         pr_info("Address spaces switched, "
 384                                 "mvcos available\n");
 385                 else
 386                         pr_info("Address spaces switched, "
 387                                 "mvcos not available\n");
 388         }
 389 #ifdef CONFIG_TRACE_IRQFLAGS
 390         sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 391         io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 392 #endif
 393 }
 394
 395 static void __init
 396 setup_lowcore(void)
 397 {
 398         struct _lowcore *lc;
 399
 400         /*
 401          * Setup lowcore for boot cpu
 402          */
 403         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 404         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 405         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 406         lc->restart_psw.addr =
 407                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 408         if (user_mode != HOME_SPACE_MODE)
 409                 lc->restart_psw.mask |= PSW_ASC_HOME;
 410         lc->external_new_psw.mask = psw_kernel_bits;
 411         lc->external_new_psw.addr =
 412                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 413         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 414         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 415         lc->program_new_psw.mask = psw_kernel_bits;
 416         lc->program_new_psw.addr =
 417                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 418         lc->mcck_new_psw.mask =
 419                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 420         lc->mcck_new_psw.addr =
 421                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 422         lc->io_new_psw.mask = psw_kernel_bits;
 423         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 424         lc->clock_comparator = -1ULL;
 425         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 426         lc->async_stack = (unsigned long)
 427                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 428         lc->panic_stack = (unsigned long)
 429                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 430         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 431         lc->thread_info = (unsigned long) &init_thread_union;
 432         lc->machine_flags = S390_lowcore.machine_flags;
 433 #ifndef CONFIG_64BIT
 434         if (MACHINE_HAS_IEEE) {
 435                 lc->extended_save_area_addr = (__u32)
 436                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 437                 /* enable extended save area */
 438                 __ctl_set_bit(14, 29);
 439         }
 440 #else
 441         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 442 #endif
 443         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 444         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 445         lc->exit_timer = S390_lowcore.exit_timer;
 446         lc->user_timer = S390_lowcore.user_timer;
 447         lc->system_timer = S390_lowcore.system_timer;
 448         lc->steal_timer = S390_lowcore.steal_timer;
 449         lc->last_update_timer = S390_lowcore.last_update_timer;
 450         lc->last_update_clock = S390_lowcore.last_update_clock;
 451         lc->ftrace_func = S390_lowcore.ftrace_func;
 452         set_prefix((u32)(unsigned long) lc);
 453         lowcore_ptr[0] = lc;
 454 }
 455
 456 static void __init
 457 setup_resources(void)
 458 {
 459         struct resource *res, *sub_res;
 460         int i;
 461
 462         code_resource.start = (unsigned long) &_text;
 463         code_resource.end = (unsigned long) &_etext - 1;
 464         data_resource.start = (unsigned long) &_etext;
 465         data_resource.end = (unsigned long) &_edata - 1;
 466
 467         for (i = 0; i < MEMORY_CHUNKS; i++) {
 468                 if (!memory_chunk[i].size)
 469                         continue;
 470                 res = alloc_bootmem_low(sizeof(struct resource));
 471                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 472                 switch (memory_chunk[i].type) {
 473                 case CHUNK_READ_WRITE:
 474                         res->name = "System RAM";
 475                         break;
 476                 case CHUNK_READ_ONLY:
 477                         res->name = "System ROM";
 478                         res->flags |= IORESOURCE_READONLY;
 479                         break;
 480                 default:
 481                         res->name = "reserved";
 482                 }
 483                 res->start = memory_chunk[i].addr;
 484                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
 485                 request_resource(&iomem_resource, res);
 486
 487                 if (code_resource.start >= res->start  &&
 488                         code_resource.start <= res->end &&
 489                         code_resource.end > res->end) {
 490                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 491                         memcpy(sub_res, &code_resource,
 492                                 sizeof(struct resource));
 493                         sub_res->end = res->end;
 494                         code_resource.start = res->end + 1;
 495                         request_resource(res, sub_res);
 496                 }
 497
 498                 if (code_resource.start >= res->start &&
 499                         code_resource.start <= res->end &&
 500                         code_resource.end <= res->end)
 501                         request_resource(res, &code_resource);
 502
 503                 if (data_resource.start >= res->start &&
 504                         data_resource.start <= res->end &&
 505                         data_resource.end > res->end) {
 506                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 507                         memcpy(sub_res, &data_resource,
 508                                 sizeof(struct resource));
 509                         sub_res->end = res->end;
 510                         data_resource.start = res->end + 1;
 511                         request_resource(res, sub_res);
 512                 }
 513
 514                 if (data_resource.start >= res->start &&
 515                         data_resource.start <= res->end &&
 516                         data_resource.end <= res->end)
 517                         request_resource(res, &data_resource);
 518         }
 519 }
 520
 521 unsigned long real_memory_size;
 522 EXPORT_SYMBOL_GPL(real_memory_size);
 523
 524 static void __init setup_memory_end(void)
 525 {
 526         unsigned long memory_size;
 527         unsigned long max_mem;
 528         int i;
 529
 530 #ifdef CONFIG_ZFCPDUMP
 531         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
 532                 memory_end = ZFCPDUMP_HSA_SIZE;
 533                 memory_end_set = 1;
 534         }
 535 #endif
 536         memory_size = 0;
 537         memory_end &= PAGE_MASK;
 538
 539         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 540         memory_end = min(max_mem, memory_end);
 541
 542         /*
 543          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 544          * extra checks that HOLES_IN_ZONE would require.
 545          */
 546         for (i = 0; i < MEMORY_CHUNKS; i++) {
 547                 unsigned long start, end;
 548                 struct mem_chunk *chunk;
 549                 unsigned long align;
 550
 551                 chunk = &memory_chunk[i];
 552                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 553                 start = (chunk->addr + align - 1) & ~(align - 1);
 554                 end = (chunk->addr + chunk->size) & ~(align - 1);
 555                 if (start >= end)
 556                         memset(chunk, 0, sizeof(*chunk));
 557                 else {
 558                         chunk->addr = start;
 559                         chunk->size = end - start;
 560                 }
 561         }
 562
 563         for (i = 0; i < MEMORY_CHUNKS; i++) {
 564                 struct mem_chunk *chunk = &memory_chunk[i];
 565
 566                 real_memory_size = max(real_memory_size,
 567                                        chunk->addr + chunk->size);
 568                 if (chunk->addr >= max_mem) {
 569                         memset(chunk, 0, sizeof(*chunk));
 570                         continue;
 571                 }
 572                 if (chunk->addr + chunk->size > max_mem)
 573                         chunk->size = max_mem - chunk->addr;
 574                 memory_size = max(memory_size, chunk->addr + chunk->size);
 575         }
 576         if (!memory_end)
 577                 memory_end = memory_size;
 578 }
 579
 580 static void __init
 581 setup_memory(void)
 582 {
 583         unsigned long bootmap_size;
 584         unsigned long start_pfn, end_pfn;
 585         int i;
 586
 587         /*
 588          * partially used pages are not usable - thus
 589          * we are rounding upwards:
 590          */
 591         start_pfn = PFN_UP(__pa(&_end));
 592         end_pfn = max_pfn = PFN_DOWN(memory_end);
 593
 594 #ifdef CONFIG_BLK_DEV_INITRD
 595         /*
 596          * Move the initrd in case the bitmap of the bootmem allocater
 597          * would overwrite it.
 598          */
 599
 600         if (INITRD_START && INITRD_SIZE) {
 601                 unsigned long bmap_size;
 602                 unsigned long start;
 603
 604                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 605                 bmap_size = PFN_PHYS(bmap_size);
 606
 607                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 608                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 609
 610                         if (start + INITRD_SIZE > memory_end) {
 611                                 pr_err("initrd extends beyond end of "
 612                                        "memory (0x%08lx > 0x%08lx) "
 613                                        "disabling initrd\n",
 614                                        start + INITRD_SIZE, memory_end);
 615                                 INITRD_START = INITRD_SIZE = 0;
 616                         } else {
 617                                 pr_info("Moving initrd (0x%08lx -> "
 618                                         "0x%08lx, size: %ld)\n",
 619                                         INITRD_START, start, INITRD_SIZE);
 620                                 memmove((void *) start, (void *) INITRD_START,
 621                                         INITRD_SIZE);
 622                                 INITRD_START = start;
 623                         }
 624                 }
 625         }
 626 #endif
 627
 628         /*
 629          * Initialize the boot-time allocator
 630          */
 631         bootmap_size = init_bootmem(start_pfn, end_pfn);
 632
 633         /*
 634          * Register RAM areas with the bootmem allocator.
 635          */
 636
 637         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 638                 unsigned long start_chunk, end_chunk, pfn;
 639
 640                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 641                         continue;
 642                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 643                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 644                 end_chunk = min(end_chunk, end_pfn);
 645                 if (start_chunk >= end_chunk)
 646                         continue;
 647                 add_active_range(0, start_chunk, end_chunk);
 648                 pfn = max(start_chunk, start_pfn);
 649                 for (; pfn < end_chunk; pfn++)
 650                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
 651         }
 652
 653         psw_set_key(PAGE_DEFAULT_KEY);
 654
 655         free_bootmem_with_active_regions(0, max_pfn);
 656
 657         /*
 658          * Reserve memory used for lowcore/command line/kernel image.
 659          */
 660         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 661         reserve_bootmem((unsigned long)_stext,
 662                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 663                         BOOTMEM_DEFAULT);
 664         /*
 665          * Reserve the bootmem bitmap itself as well. We do this in two
 666          * steps (first step was init_bootmem()) because this catches
 667          * the (very unlikely) case of us accidentally initializing the
 668          * bootmem allocator with an invalid RAM area.
 669          */
 670         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 671                         BOOTMEM_DEFAULT);
 672
 673 #ifdef CONFIG_BLK_DEV_INITRD
 674         if (INITRD_START && INITRD_SIZE) {
 675                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 676                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 677                                         BOOTMEM_DEFAULT);
 678                         initrd_start = INITRD_START;
 679                         initrd_end = initrd_start + INITRD_SIZE;
 680                 } else {
 681                         pr_err("initrd extends beyond end of "
 682                                "memory (0x%08lx > 0x%08lx) "
 683                                "disabling initrd\n",
 684                                initrd_start + INITRD_SIZE, memory_end);
 685                         initrd_start = initrd_end = 0;
 686                 }
 687         }
 688 #endif
 689 }
 690
 691 /*
 692  * Setup hardware capabilities.
 693  */
 694 static void __init setup_hwcaps(void)
 695 {
 696         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 697         unsigned long long facility_list_extended;
 698         unsigned int facility_list;
 699         int i;
 700
 701         facility_list = stfl();
 702         /*
 703          * The store facility list bits numbers as found in the principles
 704          * of operation are numbered with bit 1UL<<31 as number 0 to
 705          * bit 1UL<<0 as number 31.
 706          *   Bit 0: instructions named N3, "backported" to esa-mode
 707          *   Bit 2: z/Architecture mode is active
 708          *   Bit 7: the store-facility-list-extended facility is installed
 709          *   Bit 17: the message-security assist is installed
 710          *   Bit 19: the long-displacement facility is installed
 711          *   Bit 21: the extended-immediate facility is installed
 712          *   Bit 22: extended-translation facility 3 is installed
 713          *   Bit 30: extended-translation facility 3 enhancement facility
 714          * These get translated to:
 715          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 716          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 717          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 718          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 719          */
 720         for (i = 0; i < 6; i++)
 721                 if (facility_list & (1UL << (31 - stfl_bits[i])))
 722                         elf_hwcap |= 1UL << i;
 723
 724         if ((facility_list & (1UL << (31 - 22)))
 725             && (facility_list & (1UL << (31 - 30))))
 726                 elf_hwcap |= HWCAP_S390_ETF3EH;
 727
 728         /*
 729          * Check for additional facilities with store-facility-list-extended.
 730          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 731          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 732          * as stored by stfl, bits 32-xxx contain additional facilities.
 733          * How many facility words are stored depends on the number of
 734          * doublewords passed to the instruction. The additional facilites
 735          * are:
 736          *   Bit 42: decimal floating point facility is installed
 737          *   Bit 44: perform floating point operation facility is installed
 738          * translated to:
 739          *   HWCAP_S390_DFP bit 6 (42 && 44).
 740          */
 741         if ((elf_hwcap & (1UL << 2)) &&
 742             __stfle(&facility_list_extended, 1) > 0) {
 743                 if ((facility_list_extended & (1ULL << (63 - 42)))
 744                     && (facility_list_extended & (1ULL << (63 - 44))))
 745                         elf_hwcap |= HWCAP_S390_DFP;
 746         }
 747
 748         /*
 749          * Huge page support HWCAP_S390_HPAGE is bit 7.
 750          */
 751         if (MACHINE_HAS_HPAGE)
 752                 elf_hwcap |= HWCAP_S390_HPAGE;
 753
 754         /*
 755          * 64-bit register support for 31-bit processes
 756          * HWCAP_S390_HIGH_GPRS is bit 9.
 757          */
 758         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 759
 760         switch (S390_lowcore.cpu_id.machine) {
 761         case 0x9672:
 762 #if !defined(CONFIG_64BIT)
 763         default:        /* Use "g5" as default for 31 bit kernels. */
 764 #endif
 765                 strcpy(elf_platform, "g5");
 766                 break;
 767         case 0x2064:
 768         case 0x2066:
 769 #if defined(CONFIG_64BIT)
 770         default:        /* Use "z900" as default for 64 bit kernels. */
 771 #endif
 772                 strcpy(elf_platform, "z900");
 773                 break;
 774         case 0x2084:
 775         case 0x2086:
 776                 strcpy(elf_platform, "z990");
 777                 break;
 778         case 0x2094:
 779         case 0x2096:
 780                 strcpy(elf_platform, "z9-109");
 781                 break;
 782         case 0x2097:
 783         case 0x2098:
 784                 strcpy(elf_platform, "z10");
 785                 break;
 786         }
 787 }
 788
 789 /*
 790  * Setup function called from init/main.c just after the banner
 791  * was printed.
 792  */
 793
 794 void __init
 795 setup_arch(char **cmdline_p)
 796 {
 797         /*
 798          * print what head.S has found out about the machine
 799          */
 800 #ifndef CONFIG_64BIT
 801         if (MACHINE_IS_VM)
 802                 pr_info("Linux is running as a z/VM "
 803                         "guest operating system in 31-bit mode\n");
 804         else if (MACHINE_IS_LPAR)
 805                 pr_info("Linux is running natively in 31-bit mode\n");
 806         if (MACHINE_HAS_IEEE)
 807                 pr_info("The hardware system has IEEE compatible "
 808                         "floating point units\n");
 809         else
 810                 pr_info("The hardware system has no IEEE compatible "
 811                         "floating point units\n");
 812 #else /* CONFIG_64BIT */
 813         if (MACHINE_IS_VM)
 814                 pr_info("Linux is running as a z/VM "
 815                         "guest operating system in 64-bit mode\n");
 816         else if (MACHINE_IS_KVM)
 817                 pr_info("Linux is running under KVM in 64-bit mode\n");
 818         else if (MACHINE_IS_LPAR)
 819                 pr_info("Linux is running natively in 64-bit mode\n");
 820 #endif /* CONFIG_64BIT */
 821
 822         /* Have one command line that is parsed and saved in /proc/cmdline */
 823         /* boot_command_line has been already set up in early.c */
 824         *cmdline_p = boot_command_line;
 825
 826         ROOT_DEV = Root_RAM0;
 827
 828         init_mm.start_code = PAGE_OFFSET;
 829         init_mm.end_code = (unsigned long) &_etext;
 830         init_mm.end_data = (unsigned long) &_edata;
 831         init_mm.brk = (unsigned long) &_end;
 832
 833         if (MACHINE_HAS_MVCOS)
 834                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
 835         else
 836                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 837
 838         parse_early_param();
 839
 840         setup_ipl();
 841         setup_memory_end();
 842         setup_addressing_mode();
 843         setup_memory();
 844         setup_resources();
 845         setup_lowcore();
 846
 847         cpu_init();
 848         s390_init_cpu_topology();
 849
 850         /*
 851          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
 852          */
 853         setup_hwcaps();
 854
 855         /*
 856          * Create kernel page tables and switch to virtual addressing.
 857          */
 858         paging_init();
 859
 860         /* Setup default console */
 861         conmode_default();
 862         set_preferred_console();
 863
 864         /* Setup zfcpdump support */
 865         setup_zfcpdump(console_devno);
 866 }