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/user.h>
  29 #include <linux/tty.h>
  30 #include <linux/ioport.h>
  31 #include <linux/delay.h>
  32 #include <linux/init.h>
  33 #include <linux/initrd.h>
  34 #include <linux/bootmem.h>
  35 #include <linux/root_dev.h>
  36 #include <linux/console.h>
  37 #include <linux/kernel_stat.h>
  38 #include <linux/device.h>
  39 #include <linux/notifier.h>
  40 #include <linux/pfn.h>
  41 #include <linux/ctype.h>
  42 #include <linux/reboot.h>
  43 #include <linux/topology.h>
  44 #include <linux/ftrace.h>
  45
  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
  90 int __initdata memory_end_set;
  91 unsigned long __initdata memory_end;
  92
  93 /* An array with a pointer to the lowcore of every CPU. */
  94 struct _lowcore *lowcore_ptr[NR_CPUS];
  95 EXPORT_SYMBOL(lowcore_ptr);
  96
  97 /*
  98  * This is set up by the setup-routine at boot-time
  99  * for S390 need to find out, what we have to setup
 100  * using address 0x10400 ...
 101  */
 102
 103 #include <asm/setup.h>
 104
 105 static struct resource code_resource = {
 106         .name  = "Kernel code",
 107         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 108 };
 109
 110 static struct resource data_resource = {
 111         .name = "Kernel data",
 112         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 113 };
 114
 115 /*
 116  * cpu_init() initializes state that is per-CPU.
 117  */
 118 void __cpuinit cpu_init(void)
 119 {
 120         /*
 121          * Store processor id in lowcore (used e.g. in timer_interrupt)
 122          */
 123         get_cpu_id(&S390_lowcore.cpu_id);
 124
 125         atomic_inc(&init_mm.mm_count);
 126         current->active_mm = &init_mm;
 127         BUG_ON(current->mm);
 128         enter_lazy_tlb(&init_mm, current);
 129 }
 130
 131 /*
 132  * condev= and conmode= setup parameter.
 133  */
 134
 135 static int __init condev_setup(char *str)
 136 {
 137         int vdev;
 138
 139         vdev = simple_strtoul(str, &str, 0);
 140         if (vdev >= 0 && vdev < 65536) {
 141                 console_devno = vdev;
 142                 console_irq = -1;
 143         }
 144         return 1;
 145 }
 146
 147 __setup("condev=", condev_setup);
 148
 149 static void __init set_preferred_console(void)
 150 {
 151         if (MACHINE_IS_KVM)
 152                 add_preferred_console("hvc", 0, NULL);
 153         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 154                 add_preferred_console("ttyS", 0, NULL);
 155         else if (CONSOLE_IS_3270)
 156                 add_preferred_console("tty3270", 0, NULL);
 157 }
 158
 159 static int __init conmode_setup(char *str)
 160 {
 161 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 162         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 163                 SET_CONSOLE_SCLP;
 164 #endif
 165 #if defined(CONFIG_TN3215_CONSOLE)
 166         if (strncmp(str, "3215", 5) == 0)
 167                 SET_CONSOLE_3215;
 168 #endif
 169 #if defined(CONFIG_TN3270_CONSOLE)
 170         if (strncmp(str, "3270", 5) == 0)
 171                 SET_CONSOLE_3270;
 172 #endif
 173         set_preferred_console();
 174         return 1;
 175 }
 176
 177 __setup("conmode=", conmode_setup);
 178
 179 static void __init conmode_default(void)
 180 {
 181         char query_buffer[1024];
 182         char *ptr;
 183
 184         if (MACHINE_IS_VM) {
 185                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 186                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 187                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 188                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 189                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 190                 ptr = strstr(query_buffer, "CONMODE");
 191                 /*
 192                  * Set the conmode to 3215 so that the device recognition
 193                  * will set the cu_type of the console to 3215. If the
 194                  * conmode is 3270 and we don't set it back then both
 195                  * 3215 and the 3270 driver will try to access the console
 196                  * device (3215 as console and 3270 as normal tty).
 197                  */
 198                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 199                 if (ptr == NULL) {
 200 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 201                         SET_CONSOLE_SCLP;
 202 #endif
 203                         return;
 204                 }
 205                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 206 #if defined(CONFIG_TN3270_CONSOLE)
 207                         SET_CONSOLE_3270;
 208 #elif defined(CONFIG_TN3215_CONSOLE)
 209                         SET_CONSOLE_3215;
 210 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 211                         SET_CONSOLE_SCLP;
 212 #endif
 213                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 214 #if defined(CONFIG_TN3215_CONSOLE)
 215                         SET_CONSOLE_3215;
 216 #elif defined(CONFIG_TN3270_CONSOLE)
 217                         SET_CONSOLE_3270;
 218 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 219                         SET_CONSOLE_SCLP;
 220 #endif
 221                 }
 222         } else {
 223 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 224                 SET_CONSOLE_SCLP;
 225 #endif
 226         }
 227 }
 228
 229 #ifdef CONFIG_ZFCPDUMP
 230 static void __init setup_zfcpdump(unsigned int console_devno)
 231 {
 232         static char str[41];
 233
 234         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 235                 return;
 236         if (console_devno != -1)
 237                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 238                         ipl_info.data.fcp.dev_id.devno, console_devno);
 239         else
 240                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 241                         ipl_info.data.fcp.dev_id.devno);
 242         strcat(boot_command_line, str);
 243         console_loglevel = 2;
 244 }
 245 #else
 246 static inline void setup_zfcpdump(unsigned int console_devno) {}
 247 #endif /* CONFIG_ZFCPDUMP */
 248
 249  /*
 250  * Reboot, halt and power_off stubs. They just call _machine_restart,
 251  * _machine_halt or _machine_power_off.
 252  */
 253
 254 void machine_restart(char *command)
 255 {
 256         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 257                 /*
 258                  * Only unblank the console if we are called in enabled
 259                  * context or a bust_spinlocks cleared the way for us.
 260                  */
 261                 console_unblank();
 262         _machine_restart(command);
 263 }
 264
 265 void machine_halt(void)
 266 {
 267         if (!in_interrupt() || oops_in_progress)
 268                 /*
 269                  * Only unblank the console if we are called in enabled
 270                  * context or a bust_spinlocks cleared the way for us.
 271                  */
 272                 console_unblank();
 273         _machine_halt();
 274 }
 275
 276 void machine_power_off(void)
 277 {
 278         if (!in_interrupt() || oops_in_progress)
 279                 /*
 280                  * Only unblank the console if we are called in enabled
 281                  * context or a bust_spinlocks cleared the way for us.
 282                  */
 283                 console_unblank();
 284         _machine_power_off();
 285 }
 286
 287 /*
 288  * Dummy power off function.
 289  */
 290 void (*pm_power_off)(void) = machine_power_off;
 291
 292 static int __init early_parse_mem(char *p)
 293 {
 294         memory_end = memparse(p, &p);
 295         memory_end_set = 1;
 296         return 0;
 297 }
 298 early_param("mem", early_parse_mem);
 299
 300 unsigned int user_mode = HOME_SPACE_MODE;
 301 EXPORT_SYMBOL_GPL(user_mode);
 302
 303 static int set_amode_and_uaccess(unsigned long user_amode,
 304                                  unsigned long user32_amode)
 305 {
 306         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 307                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 308                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 309 #ifdef CONFIG_COMPAT
 310         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 311                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 312                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 313         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 314                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 315                           PSW32_MASK_PSTATE;
 316 #endif
 317         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 318                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 319
 320         if (MACHINE_HAS_MVCOS) {
 321                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 322                 return 1;
 323         } else {
 324                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 325                 return 0;
 326         }
 327 }
 328
 329 /*
 330  * Switch kernel/user addressing modes?
 331  */
 332 static int __init early_parse_switch_amode(char *p)
 333 {
 334         if (user_mode != SECONDARY_SPACE_MODE)
 335                 user_mode = PRIMARY_SPACE_MODE;
 336         return 0;
 337 }
 338 early_param("switch_amode", early_parse_switch_amode);
 339
 340 static int __init early_parse_user_mode(char *p)
 341 {
 342         if (p && strcmp(p, "primary") == 0)
 343                 user_mode = PRIMARY_SPACE_MODE;
 344 #ifdef CONFIG_S390_EXEC_PROTECT
 345         else if (p && strcmp(p, "secondary") == 0)
 346                 user_mode = SECONDARY_SPACE_MODE;
 347 #endif
 348         else if (!p || strcmp(p, "home") == 0)
 349                 user_mode = HOME_SPACE_MODE;
 350         else
 351                 return 1;
 352         return 0;
 353 }
 354 early_param("user_mode", early_parse_user_mode);
 355
 356 #ifdef CONFIG_S390_EXEC_PROTECT
 357 /*
 358  * Enable execute protection?
 359  */
 360 static int __init early_parse_noexec(char *p)
 361 {
 362         if (!strncmp(p, "off", 3))
 363                 return 0;
 364         user_mode = SECONDARY_SPACE_MODE;
 365         return 0;
 366 }
 367 early_param("noexec", early_parse_noexec);
 368 #endif /* CONFIG_S390_EXEC_PROTECT */
 369
 370 static void setup_addressing_mode(void)
 371 {
 372         if (user_mode == SECONDARY_SPACE_MODE) {
 373                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
 374                                           PSW32_ASC_SECONDARY))
 375                         pr_info("Execute protection active, "
 376                                 "mvcos available\n");
 377                 else
 378                         pr_info("Execute protection active, "
 379                                 "mvcos not available\n");
 380         } else if (user_mode == PRIMARY_SPACE_MODE) {
 381                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 382                         pr_info("Address spaces switched, "
 383                                 "mvcos available\n");
 384                 else
 385                         pr_info("Address spaces switched, "
 386                                 "mvcos not available\n");
 387         }
 388 #ifdef CONFIG_TRACE_IRQFLAGS
 389         sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 390         io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 391 #endif
 392 }
 393
 394 static void __init
 395 setup_lowcore(void)
 396 {
 397         struct _lowcore *lc;
 398
 399         /*
 400          * Setup lowcore for boot cpu
 401          */
 402         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 403         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 404         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 405         lc->restart_psw.addr =
 406                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 407         if (user_mode != HOME_SPACE_MODE)
 408                 lc->restart_psw.mask |= PSW_ASC_HOME;
 409         lc->external_new_psw.mask = psw_kernel_bits;
 410         lc->external_new_psw.addr =
 411                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 412         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 413         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 414         lc->program_new_psw.mask = psw_kernel_bits;
 415         lc->program_new_psw.addr =
 416                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 417         lc->mcck_new_psw.mask =
 418                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 419         lc->mcck_new_psw.addr =
 420                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 421         lc->io_new_psw.mask = psw_kernel_bits;
 422         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 423         lc->clock_comparator = -1ULL;
 424         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 425         lc->async_stack = (unsigned long)
 426                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 427         lc->panic_stack = (unsigned long)
 428                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 429         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 430         lc->thread_info = (unsigned long) &init_thread_union;
 431         lc->machine_flags = S390_lowcore.machine_flags;
 432 #ifndef CONFIG_64BIT
 433         if (MACHINE_HAS_IEEE) {
 434                 lc->extended_save_area_addr = (__u32)
 435                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 436                 /* enable extended save area */
 437                 __ctl_set_bit(14, 29);
 438         }
 439 #else
 440         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 441 #endif
 442         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 443         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 444         lc->exit_timer = S390_lowcore.exit_timer;
 445         lc->user_timer = S390_lowcore.user_timer;
 446         lc->system_timer = S390_lowcore.system_timer;
 447         lc->steal_timer = S390_lowcore.steal_timer;
 448         lc->last_update_timer = S390_lowcore.last_update_timer;
 449         lc->last_update_clock = S390_lowcore.last_update_clock;
 450         lc->ftrace_func = S390_lowcore.ftrace_func;
 451         set_prefix((u32)(unsigned long) lc);
 452         lowcore_ptr[0] = lc;
 453 }
 454
 455 static void __init
 456 setup_resources(void)
 457 {
 458         struct resource *res, *sub_res;
 459         int i;
 460
 461         code_resource.start = (unsigned long) &_text;
 462         code_resource.end = (unsigned long) &_etext - 1;
 463         data_resource.start = (unsigned long) &_etext;
 464         data_resource.end = (unsigned long) &_edata - 1;
 465
 466         for (i = 0; i < MEMORY_CHUNKS; i++) {
 467                 if (!memory_chunk[i].size)
 468                         continue;
 469                 res = alloc_bootmem_low(sizeof(struct resource));
 470                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 471                 switch (memory_chunk[i].type) {
 472                 case CHUNK_READ_WRITE:
 473                         res->name = "System RAM";
 474                         break;
 475                 case CHUNK_READ_ONLY:
 476                         res->name = "System ROM";
 477                         res->flags |= IORESOURCE_READONLY;
 478                         break;
 479                 default:
 480                         res->name = "reserved";
 481                 }
 482                 res->start = memory_chunk[i].addr;
 483                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
 484                 request_resource(&iomem_resource, res);
 485
 486                 if (code_resource.start >= res->start  &&
 487                         code_resource.start <= res->end &&
 488                         code_resource.end > res->end) {
 489                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 490                         memcpy(sub_res, &code_resource,
 491                                 sizeof(struct resource));
 492                         sub_res->end = res->end;
 493                         code_resource.start = res->end + 1;
 494                         request_resource(res, sub_res);
 495                 }
 496
 497                 if (code_resource.start >= res->start &&
 498                         code_resource.start <= res->end &&
 499                         code_resource.end <= res->end)
 500                         request_resource(res, &code_resource);
 501
 502                 if (data_resource.start >= res->start &&
 503                         data_resource.start <= res->end &&
 504                         data_resource.end > res->end) {
 505                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 506                         memcpy(sub_res, &data_resource,
 507                                 sizeof(struct resource));
 508                         sub_res->end = res->end;
 509                         data_resource.start = res->end + 1;
 510                         request_resource(res, sub_res);
 511                 }
 512
 513                 if (data_resource.start >= res->start &&
 514                         data_resource.start <= res->end &&
 515                         data_resource.end <= res->end)
 516                         request_resource(res, &data_resource);
 517         }
 518 }
 519
 520 unsigned long real_memory_size;
 521 EXPORT_SYMBOL_GPL(real_memory_size);
 522
 523 static void __init setup_memory_end(void)
 524 {
 525         unsigned long memory_size;
 526         unsigned long max_mem;
 527         int i;
 528
 529 #ifdef CONFIG_ZFCPDUMP
 530         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
 531                 memory_end = ZFCPDUMP_HSA_SIZE;
 532                 memory_end_set = 1;
 533         }
 534 #endif
 535         memory_size = 0;
 536         memory_end &= PAGE_MASK;
 537
 538         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 539         memory_end = min(max_mem, memory_end);
 540
 541         /*
 542          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 543          * extra checks that HOLES_IN_ZONE would require.
 544          */
 545         for (i = 0; i < MEMORY_CHUNKS; i++) {
 546                 unsigned long start, end;
 547                 struct mem_chunk *chunk;
 548                 unsigned long align;
 549
 550                 chunk = &memory_chunk[i];
 551                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 552                 start = (chunk->addr + align - 1) & ~(align - 1);
 553                 end = (chunk->addr + chunk->size) & ~(align - 1);
 554                 if (start >= end)
 555                         memset(chunk, 0, sizeof(*chunk));
 556                 else {
 557                         chunk->addr = start;
 558                         chunk->size = end - start;
 559                 }
 560         }
 561
 562         for (i = 0; i < MEMORY_CHUNKS; i++) {
 563                 struct mem_chunk *chunk = &memory_chunk[i];
 564
 565                 real_memory_size = max(real_memory_size,
 566                                        chunk->addr + chunk->size);
 567                 if (chunk->addr >= max_mem) {
 568                         memset(chunk, 0, sizeof(*chunk));
 569                         continue;
 570                 }
 571                 if (chunk->addr + chunk->size > max_mem)
 572                         chunk->size = max_mem - chunk->addr;
 573                 memory_size = max(memory_size, chunk->addr + chunk->size);
 574         }
 575         if (!memory_end)
 576                 memory_end = memory_size;
 577 }
 578
 579 static void __init
 580 setup_memory(void)
 581 {
 582         unsigned long bootmap_size;
 583         unsigned long start_pfn, end_pfn;
 584         int i;
 585
 586         /*
 587          * partially used pages are not usable - thus
 588          * we are rounding upwards:
 589          */
 590         start_pfn = PFN_UP(__pa(&_end));
 591         end_pfn = max_pfn = PFN_DOWN(memory_end);
 592
 593 #ifdef CONFIG_BLK_DEV_INITRD
 594         /*
 595          * Move the initrd in case the bitmap of the bootmem allocater
 596          * would overwrite it.
 597          */
 598
 599         if (INITRD_START && INITRD_SIZE) {
 600                 unsigned long bmap_size;
 601                 unsigned long start;
 602
 603                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 604                 bmap_size = PFN_PHYS(bmap_size);
 605
 606                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 607                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 608
 609                         if (start + INITRD_SIZE > memory_end) {
 610                                 pr_err("initrd extends beyond end of "
 611                                        "memory (0x%08lx > 0x%08lx) "
 612                                        "disabling initrd\n",
 613                                        start + INITRD_SIZE, memory_end);
 614                                 INITRD_START = INITRD_SIZE = 0;
 615                         } else {
 616                                 pr_info("Moving initrd (0x%08lx -> "
 617                                         "0x%08lx, size: %ld)\n",
 618                                         INITRD_START, start, INITRD_SIZE);
 619                                 memmove((void *) start, (void *) INITRD_START,
 620                                         INITRD_SIZE);
 621                                 INITRD_START = start;
 622                         }
 623                 }
 624         }
 625 #endif
 626
 627         /*
 628          * Initialize the boot-time allocator
 629          */
 630         bootmap_size = init_bootmem(start_pfn, end_pfn);
 631
 632         /*
 633          * Register RAM areas with the bootmem allocator.
 634          */
 635
 636         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 637                 unsigned long start_chunk, end_chunk, pfn;
 638
 639                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 640                         continue;
 641                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 642                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 643                 end_chunk = min(end_chunk, end_pfn);
 644                 if (start_chunk >= end_chunk)
 645                         continue;
 646                 add_active_range(0, start_chunk, end_chunk);
 647                 pfn = max(start_chunk, start_pfn);
 648                 for (; pfn < end_chunk; pfn++)
 649                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
 650         }
 651
 652         psw_set_key(PAGE_DEFAULT_KEY);
 653
 654         free_bootmem_with_active_regions(0, max_pfn);
 655
 656         /*
 657          * Reserve memory used for lowcore/command line/kernel image.
 658          */
 659         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 660         reserve_bootmem((unsigned long)_stext,
 661                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 662                         BOOTMEM_DEFAULT);
 663         /*
 664          * Reserve the bootmem bitmap itself as well. We do this in two
 665          * steps (first step was init_bootmem()) because this catches
 666          * the (very unlikely) case of us accidentally initializing the
 667          * bootmem allocator with an invalid RAM area.
 668          */
 669         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 670                         BOOTMEM_DEFAULT);
 671
 672 #ifdef CONFIG_BLK_DEV_INITRD
 673         if (INITRD_START && INITRD_SIZE) {
 674                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 675                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 676                                         BOOTMEM_DEFAULT);
 677                         initrd_start = INITRD_START;
 678                         initrd_end = initrd_start + INITRD_SIZE;
 679                 } else {
 680                         pr_err("initrd extends beyond end of "
 681                                "memory (0x%08lx > 0x%08lx) "
 682                                "disabling initrd\n",
 683                                initrd_start + INITRD_SIZE, memory_end);
 684                         initrd_start = initrd_end = 0;
 685                 }
 686         }
 687 #endif
 688 }
 689
 690 /*
 691  * Setup hardware capabilities.
 692  */
 693 static void __init setup_hwcaps(void)
 694 {
 695         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 696         unsigned long long facility_list_extended;
 697         unsigned int facility_list;
 698         int i;
 699
 700         facility_list = stfl();
 701         /*
 702          * The store facility list bits numbers as found in the principles
 703          * of operation are numbered with bit 1UL<<31 as number 0 to
 704          * bit 1UL<<0 as number 31.
 705          *   Bit 0: instructions named N3, "backported" to esa-mode
 706          *   Bit 2: z/Architecture mode is active
 707          *   Bit 7: the store-facility-list-extended facility is installed
 708          *   Bit 17: the message-security assist is installed
 709          *   Bit 19: the long-displacement facility is installed
 710          *   Bit 21: the extended-immediate facility is installed
 711          *   Bit 22: extended-translation facility 3 is installed
 712          *   Bit 30: extended-translation facility 3 enhancement facility
 713          * These get translated to:
 714          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 715          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 716          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 717          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 718          */
 719         for (i = 0; i < 6; i++)
 720                 if (facility_list & (1UL << (31 - stfl_bits[i])))
 721                         elf_hwcap |= 1UL << i;
 722
 723         if ((facility_list & (1UL << (31 - 22)))
 724             && (facility_list & (1UL << (31 - 30))))
 725                 elf_hwcap |= HWCAP_S390_ETF3EH;
 726
 727         /*
 728          * Check for additional facilities with store-facility-list-extended.
 729          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 730          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 731          * as stored by stfl, bits 32-xxx contain additional facilities.
 732          * How many facility words are stored depends on the number of
 733          * doublewords passed to the instruction. The additional facilites
 734          * are:
 735          *   Bit 42: decimal floating point facility is installed
 736          *   Bit 44: perform floating point operation facility is installed
 737          * translated to:
 738          *   HWCAP_S390_DFP bit 6 (42 && 44).
 739          */
 740         if ((elf_hwcap & (1UL << 2)) &&
 741             __stfle(&facility_list_extended, 1) > 0) {
 742                 if ((facility_list_extended & (1ULL << (63 - 42)))
 743                     && (facility_list_extended & (1ULL << (63 - 44))))
 744                         elf_hwcap |= HWCAP_S390_DFP;
 745         }
 746
 747         /*
 748          * Huge page support HWCAP_S390_HPAGE is bit 7.
 749          */
 750         if (MACHINE_HAS_HPAGE)
 751                 elf_hwcap |= HWCAP_S390_HPAGE;
 752
 753         /*
 754          * 64-bit register support for 31-bit processes
 755          * HWCAP_S390_HIGH_GPRS is bit 9.
 756          */
 757         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 758
 759         switch (S390_lowcore.cpu_id.machine) {
 760         case 0x9672:
 761 #if !defined(CONFIG_64BIT)
 762         default:        /* Use "g5" as default for 31 bit kernels. */
 763 #endif
 764                 strcpy(elf_platform, "g5");
 765                 break;
 766         case 0x2064:
 767         case 0x2066:
 768 #if defined(CONFIG_64BIT)
 769         default:        /* Use "z900" as default for 64 bit kernels. */
 770 #endif
 771                 strcpy(elf_platform, "z900");
 772                 break;
 773         case 0x2084:
 774         case 0x2086:
 775                 strcpy(elf_platform, "z990");
 776                 break;
 777         case 0x2094:
 778         case 0x2096:
 779                 strcpy(elf_platform, "z9-109");
 780                 break;
 781         case 0x2097:
 782         case 0x2098:
 783                 strcpy(elf_platform, "z10");
 784                 break;
 785         }
 786 }
 787
 788 /*
 789  * Setup function called from init/main.c just after the banner
 790  * was printed.
 791  */
 792
 793 void __init
 794 setup_arch(char **cmdline_p)
 795 {
 796         /*
 797          * print what head.S has found out about the machine
 798          */
 799 #ifndef CONFIG_64BIT
 800         if (MACHINE_IS_VM)
 801                 pr_info("Linux is running as a z/VM "
 802                         "guest operating system in 31-bit mode\n");
 803         else if (MACHINE_IS_LPAR)
 804                 pr_info("Linux is running natively in 31-bit mode\n");
 805         if (MACHINE_HAS_IEEE)
 806                 pr_info("The hardware system has IEEE compatible "
 807                         "floating point units\n");
 808         else
 809                 pr_info("The hardware system has no IEEE compatible "
 810                         "floating point units\n");
 811 #else /* CONFIG_64BIT */
 812         if (MACHINE_IS_VM)
 813                 pr_info("Linux is running as a z/VM "
 814                         "guest operating system in 64-bit mode\n");
 815         else if (MACHINE_IS_KVM)
 816                 pr_info("Linux is running under KVM in 64-bit mode\n");
 817         else if (MACHINE_IS_LPAR)
 818                 pr_info("Linux is running natively in 64-bit mode\n");
 819 #endif /* CONFIG_64BIT */
 820
 821         /* Have one command line that is parsed and saved in /proc/cmdline */
 822         /* boot_command_line has been already set up in early.c */
 823         *cmdline_p = boot_command_line;
 824
 825         ROOT_DEV = Root_RAM0;
 826
 827         init_mm.start_code = PAGE_OFFSET;
 828         init_mm.end_code = (unsigned long) &_etext;
 829         init_mm.end_data = (unsigned long) &_edata;
 830         init_mm.brk = (unsigned long) &_end;
 831
 832         if (MACHINE_HAS_MVCOS)
 833                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
 834         else
 835                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 836
 837         parse_early_param();
 838
 839         setup_ipl();
 840         setup_memory_end();
 841         setup_addressing_mode();
 842         setup_memory();
 843         setup_resources();
 844         setup_lowcore();
 845
 846         cpu_init();
 847         s390_init_cpu_topology();
 848
 849         /*
 850          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
 851          */
 852         setup_hwcaps();
 853
 854         /*
 855          * Create kernel page tables and switch to virtual addressing.
 856          */
 857         paging_init();
 858
 859         /* Setup default console */
 860         conmode_default();
 861         set_preferred_console();
 862
 863         /* Setup zfcpdump support */
 864         setup_zfcpdump(console_devno);
 865 }