arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) IBM Corp. 1999,2012
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "arch/i386/kernel/setup.c"
  10  *    Copyright (C) 1995, Linus Torvalds
  11  */
  12
  13 /*
  14  * This file handles the architecture-dependent parts of initialization
  15  */
  16
  17 #define KMSG_COMPONENT "setup"
  18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  19
  20 #include <linux/errno.h>
  21 #include <linux/module.h>
  22 #include <linux/sched.h>
  23 #include <linux/kernel.h>
  24 #include <linux/memblock.h>
  25 #include <linux/mm.h>
  26 #include <linux/stddef.h>
  27 #include <linux/unistd.h>
  28 #include <linux/ptrace.h>
  29 #include <linux/user.h>
  30 #include <linux/tty.h>
  31 #include <linux/ioport.h>
  32 #include <linux/delay.h>
  33 #include <linux/init.h>
  34 #include <linux/initrd.h>
  35 #include <linux/bootmem.h>
  36 #include <linux/root_dev.h>
  37 #include <linux/console.h>
  38 #include <linux/kernel_stat.h>
  39 #include <linux/device.h>
  40 #include <linux/notifier.h>
  41 #include <linux/pfn.h>
  42 #include <linux/ctype.h>
  43 #include <linux/reboot.h>
  44 #include <linux/topology.h>
  45 #include <linux/ftrace.h>
  46 #include <linux/kexec.h>
  47 #include <linux/crash_dump.h>
  48 #include <linux/memory.h>
  49 #include <linux/compat.h>
  50
  51 #include <asm/ipl.h>
  52 #include <asm/uaccess.h>
  53 #include <asm/smp.h>
  54 #include <asm/mmu_context.h>
  55 #include <asm/cpcmd.h>
  56 #include <asm/lowcore.h>
  57 #include <asm/irq.h>
  58 #include <asm/page.h>
  59 #include <asm/ptrace.h>
  60 #include <asm/sections.h>
  61 #include <asm/ebcdic.h>
  62 #include <asm/kvm_virtio.h>
  63 #include <asm/diag.h>
  64 #include <asm/os_info.h>
  65 #include "entry.h"
  66
  67 long psw_kernel_bits    = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
  68                           PSW_MASK_EA | PSW_MASK_BA;
  69 long psw_user_bits      = PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
  70                           PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
  71                           PSW_MASK_PSTATE | PSW_ASC_HOME;
  72
  73 /*
  74  * User copy operations.
  75  */
  76 struct uaccess_ops uaccess;
  77 EXPORT_SYMBOL(uaccess);
  78
  79 /*
  80  * Machine setup..
  81  */
  82 unsigned int console_mode = 0;
  83 EXPORT_SYMBOL(console_mode);
  84
  85 unsigned int console_devno = -1;
  86 EXPORT_SYMBOL(console_devno);
  87
  88 unsigned int console_irq = -1;
  89 EXPORT_SYMBOL(console_irq);
  90
  91 unsigned long elf_hwcap = 0;
  92 char elf_platform[ELF_PLATFORM_SIZE];
  93
  94 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  95
  96 int __initdata memory_end_set;
  97 unsigned long __initdata memory_end;
  98
  99 unsigned long VMALLOC_START;
 100 EXPORT_SYMBOL(VMALLOC_START);
 101
 102 unsigned long VMALLOC_END;
 103 EXPORT_SYMBOL(VMALLOC_END);
 104
 105 struct page *vmemmap;
 106 EXPORT_SYMBOL(vmemmap);
 107
 108 /* An array with a pointer to the lowcore of every CPU. */
 109 struct _lowcore *lowcore_ptr[NR_CPUS];
 110 EXPORT_SYMBOL(lowcore_ptr);
 111
 112 /*
 113  * This is set up by the setup-routine at boot-time
 114  * for S390 need to find out, what we have to setup
 115  * using address 0x10400 ...
 116  */
 117
 118 #include <asm/setup.h>
 119
 120 /*
 121  * condev= and conmode= setup parameter.
 122  */
 123
 124 static int __init condev_setup(char *str)
 125 {
 126         int vdev;
 127
 128         vdev = simple_strtoul(str, &str, 0);
 129         if (vdev >= 0 && vdev < 65536) {
 130                 console_devno = vdev;
 131                 console_irq = -1;
 132         }
 133         return 1;
 134 }
 135
 136 __setup("condev=", condev_setup);
 137
 138 static void __init set_preferred_console(void)
 139 {
 140         if (MACHINE_IS_KVM)
 141                 add_preferred_console("hvc", 0, NULL);
 142         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 143                 add_preferred_console("ttyS", 0, NULL);
 144         else if (CONSOLE_IS_3270)
 145                 add_preferred_console("tty3270", 0, NULL);
 146 }
 147
 148 static int __init conmode_setup(char *str)
 149 {
 150 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 151         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 152                 SET_CONSOLE_SCLP;
 153 #endif
 154 #if defined(CONFIG_TN3215_CONSOLE)
 155         if (strncmp(str, "3215", 5) == 0)
 156                 SET_CONSOLE_3215;
 157 #endif
 158 #if defined(CONFIG_TN3270_CONSOLE)
 159         if (strncmp(str, "3270", 5) == 0)
 160                 SET_CONSOLE_3270;
 161 #endif
 162         set_preferred_console();
 163         return 1;
 164 }
 165
 166 __setup("conmode=", conmode_setup);
 167
 168 static void __init conmode_default(void)
 169 {
 170         char query_buffer[1024];
 171         char *ptr;
 172
 173         if (MACHINE_IS_VM) {
 174                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 175                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 176                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 177                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 178                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 179                 ptr = strstr(query_buffer, "CONMODE");
 180                 /*
 181                  * Set the conmode to 3215 so that the device recognition
 182                  * will set the cu_type of the console to 3215. If the
 183                  * conmode is 3270 and we don't set it back then both
 184                  * 3215 and the 3270 driver will try to access the console
 185                  * device (3215 as console and 3270 as normal tty).
 186                  */
 187                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 188                 if (ptr == NULL) {
 189 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 190                         SET_CONSOLE_SCLP;
 191 #endif
 192                         return;
 193                 }
 194                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 195 #if defined(CONFIG_TN3270_CONSOLE)
 196                         SET_CONSOLE_3270;
 197 #elif defined(CONFIG_TN3215_CONSOLE)
 198                         SET_CONSOLE_3215;
 199 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 200                         SET_CONSOLE_SCLP;
 201 #endif
 202                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 203 #if defined(CONFIG_TN3215_CONSOLE)
 204                         SET_CONSOLE_3215;
 205 #elif defined(CONFIG_TN3270_CONSOLE)
 206                         SET_CONSOLE_3270;
 207 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 208                         SET_CONSOLE_SCLP;
 209 #endif
 210                 }
 211         } else {
 212 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 213                 SET_CONSOLE_SCLP;
 214 #endif
 215         }
 216 }
 217
 218 #ifdef CONFIG_ZFCPDUMP
 219 static void __init setup_zfcpdump(unsigned int console_devno)
 220 {
 221         static char str[41];
 222
 223         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 224                 return;
 225         if (OLDMEM_BASE)
 226                 return;
 227         if (console_devno != -1)
 228                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 229                         ipl_info.data.fcp.dev_id.devno, console_devno);
 230         else
 231                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 232                         ipl_info.data.fcp.dev_id.devno);
 233         strcat(boot_command_line, str);
 234         console_loglevel = 2;
 235 }
 236 #else
 237 static inline void setup_zfcpdump(unsigned int console_devno) {}
 238 #endif /* CONFIG_ZFCPDUMP */
 239
 240  /*
 241  * Reboot, halt and power_off stubs. They just call _machine_restart,
 242  * _machine_halt or _machine_power_off.
 243  */
 244
 245 void machine_restart(char *command)
 246 {
 247         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 248                 /*
 249                  * Only unblank the console if we are called in enabled
 250                  * context or a bust_spinlocks cleared the way for us.
 251                  */
 252                 console_unblank();
 253         _machine_restart(command);
 254 }
 255
 256 void machine_halt(void)
 257 {
 258         if (!in_interrupt() || oops_in_progress)
 259                 /*
 260                  * Only unblank the console if we are called in enabled
 261                  * context or a bust_spinlocks cleared the way for us.
 262                  */
 263                 console_unblank();
 264         _machine_halt();
 265 }
 266
 267 void machine_power_off(void)
 268 {
 269         if (!in_interrupt() || oops_in_progress)
 270                 /*
 271                  * Only unblank the console if we are called in enabled
 272                  * context or a bust_spinlocks cleared the way for us.
 273                  */
 274                 console_unblank();
 275         _machine_power_off();
 276 }
 277
 278 /*
 279  * Dummy power off function.
 280  */
 281 void (*pm_power_off)(void) = machine_power_off;
 282
 283 static int __init early_parse_mem(char *p)
 284 {
 285         memory_end = memparse(p, &p);
 286         memory_end_set = 1;
 287         return 0;
 288 }
 289 early_param("mem", early_parse_mem);
 290
 291 static int __init parse_vmalloc(char *arg)
 292 {
 293         if (!arg)
 294                 return -EINVAL;
 295         VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
 296         return 0;
 297 }
 298 early_param("vmalloc", parse_vmalloc);
 299
 300 unsigned int user_mode = HOME_SPACE_MODE;
 301 EXPORT_SYMBOL_GPL(user_mode);
 302
 303 static int set_amode_primary(void)
 304 {
 305         psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
 306         psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
 307 #ifdef CONFIG_COMPAT
 308         psw32_user_bits =
 309                 (psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
 310 #endif
 311
 312         if (MACHINE_HAS_MVCOS) {
 313                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 314                 return 1;
 315         } else {
 316                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 317                 return 0;
 318         }
 319 }
 320
 321 /*
 322  * Switch kernel/user addressing modes?
 323  */
 324 static int __init early_parse_switch_amode(char *p)
 325 {
 326         user_mode = PRIMARY_SPACE_MODE;
 327         return 0;
 328 }
 329 early_param("switch_amode", early_parse_switch_amode);
 330
 331 static int __init early_parse_user_mode(char *p)
 332 {
 333         if (p && strcmp(p, "primary") == 0)
 334                 user_mode = PRIMARY_SPACE_MODE;
 335         else if (!p || strcmp(p, "home") == 0)
 336                 user_mode = HOME_SPACE_MODE;
 337         else
 338                 return 1;
 339         return 0;
 340 }
 341 early_param("user_mode", early_parse_user_mode);
 342
 343 static void setup_addressing_mode(void)
 344 {
 345         if (user_mode == PRIMARY_SPACE_MODE) {
 346                 if (set_amode_primary())
 347                         pr_info("Address spaces switched, "
 348                                 "mvcos available\n");
 349                 else
 350                         pr_info("Address spaces switched, "
 351                                 "mvcos not available\n");
 352         }
 353 }
 354
 355 void *restart_stack __attribute__((__section__(".data")));
 356
 357 static void __init setup_lowcore(void)
 358 {
 359         struct _lowcore *lc;
 360
 361         /*
 362          * Setup lowcore for boot cpu
 363          */
 364         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 365         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 366         lc->restart_psw.mask = psw_kernel_bits;
 367         lc->restart_psw.addr =
 368                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 369         lc->external_new_psw.mask = psw_kernel_bits |
 370                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 371         lc->external_new_psw.addr =
 372                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 373         lc->svc_new_psw.mask = psw_kernel_bits |
 374                 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 375         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 376         lc->program_new_psw.mask = psw_kernel_bits |
 377                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 378         lc->program_new_psw.addr =
 379                 PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
 380         lc->mcck_new_psw.mask = psw_kernel_bits;
 381         lc->mcck_new_psw.addr =
 382                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 383         lc->io_new_psw.mask = psw_kernel_bits |
 384                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 385         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 386         lc->clock_comparator = -1ULL;
 387         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 388         lc->async_stack = (unsigned long)
 389                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 390         lc->panic_stack = (unsigned long)
 391                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 392         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 393         lc->thread_info = (unsigned long) &init_thread_union;
 394         lc->machine_flags = S390_lowcore.machine_flags;
 395         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 396         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 397                MAX_FACILITY_BIT/8);
 398 #ifndef CONFIG_64BIT
 399         if (MACHINE_HAS_IEEE) {
 400                 lc->extended_save_area_addr = (__u32)
 401                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 402                 /* enable extended save area */
 403                 __ctl_set_bit(14, 29);
 404         }
 405 #else
 406         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 407 #endif
 408         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 409         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 410         lc->exit_timer = S390_lowcore.exit_timer;
 411         lc->user_timer = S390_lowcore.user_timer;
 412         lc->system_timer = S390_lowcore.system_timer;
 413         lc->steal_timer = S390_lowcore.steal_timer;
 414         lc->last_update_timer = S390_lowcore.last_update_timer;
 415         lc->last_update_clock = S390_lowcore.last_update_clock;
 416         lc->ftrace_func = S390_lowcore.ftrace_func;
 417
 418         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
 419         restart_stack += ASYNC_SIZE;
 420
 421         /*
 422          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 423          * restart data to the absolute zero lowcore. This is necesary if
 424          * PSW restart is done on an offline CPU that has lowcore zero.
 425          */
 426         lc->restart_stack = (unsigned long) restart_stack;
 427         lc->restart_fn = (unsigned long) do_restart;
 428         lc->restart_data = 0;
 429         lc->restart_source = -1UL;
 430         memcpy(&S390_lowcore.restart_stack, &lc->restart_stack,
 431                4*sizeof(unsigned long));
 432         copy_to_absolute_zero(&S390_lowcore.restart_psw,
 433                               &lc->restart_psw, sizeof(psw_t));
 434
 435         set_prefix((u32)(unsigned long) lc);
 436         lowcore_ptr[0] = lc;
 437 }
 438
 439 static struct resource code_resource = {
 440         .name  = "Kernel code",
 441         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 442 };
 443
 444 static struct resource data_resource = {
 445         .name = "Kernel data",
 446         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 447 };
 448
 449 static struct resource bss_resource = {
 450         .name = "Kernel bss",
 451         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 452 };
 453
 454 static struct resource __initdata *standard_resources[] = {
 455         &code_resource,
 456         &data_resource,
 457         &bss_resource,
 458 };
 459
 460 static void __init setup_resources(void)
 461 {
 462         struct resource *res, *std_res, *sub_res;
 463         int i, j;
 464
 465         code_resource.start = (unsigned long) &_text;
 466         code_resource.end = (unsigned long) &_etext - 1;
 467         data_resource.start = (unsigned long) &_etext;
 468         data_resource.end = (unsigned long) &_edata - 1;
 469         bss_resource.start = (unsigned long) &__bss_start;
 470         bss_resource.end = (unsigned long) &__bss_stop - 1;
 471
 472         for (i = 0; i < MEMORY_CHUNKS; i++) {
 473                 if (!memory_chunk[i].size)
 474                         continue;
 475                 if (memory_chunk[i].type == CHUNK_OLDMEM ||
 476                     memory_chunk[i].type == CHUNK_CRASHK)
 477                         continue;
 478                 res = alloc_bootmem_low(sizeof(*res));
 479                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 480                 switch (memory_chunk[i].type) {
 481                 case CHUNK_READ_WRITE:
 482                 case CHUNK_CRASHK:
 483                         res->name = "System RAM";
 484                         break;
 485                 case CHUNK_READ_ONLY:
 486                         res->name = "System ROM";
 487                         res->flags |= IORESOURCE_READONLY;
 488                         break;
 489                 default:
 490                         res->name = "reserved";
 491                 }
 492                 res->start = memory_chunk[i].addr;
 493                 res->end = res->start + memory_chunk[i].size - 1;
 494                 request_resource(&iomem_resource, res);
 495
 496                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 497                         std_res = standard_resources[j];
 498                         if (std_res->start < res->start ||
 499                             std_res->start > res->end)
 500                                 continue;
 501                         if (std_res->end > res->end) {
 502                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 503                                 *sub_res = *std_res;
 504                                 sub_res->end = res->end;
 505                                 std_res->start = res->end + 1;
 506                                 request_resource(res, sub_res);
 507                         } else {
 508                                 request_resource(res, std_res);
 509                         }
 510                 }
 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 vmax, vmalloc_size, tmp;
 520         int i;
 521
 522
 523 #ifdef CONFIG_ZFCPDUMP
 524         if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
 525                 memory_end = ZFCPDUMP_HSA_SIZE;
 526                 memory_end_set = 1;
 527         }
 528 #endif
 529         real_memory_size = 0;
 530         memory_end &= PAGE_MASK;
 531
 532         /*
 533          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 534          * extra checks that HOLES_IN_ZONE would require.
 535          */
 536         for (i = 0; i < MEMORY_CHUNKS; i++) {
 537                 unsigned long start, end;
 538                 struct mem_chunk *chunk;
 539                 unsigned long align;
 540
 541                 chunk = &memory_chunk[i];
 542                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 543                 start = (chunk->addr + align - 1) & ~(align - 1);
 544                 end = (chunk->addr + chunk->size) & ~(align - 1);
 545                 if (start >= end)
 546                         memset(chunk, 0, sizeof(*chunk));
 547                 else {
 548                         chunk->addr = start;
 549                         chunk->size = end - start;
 550                 }
 551                 real_memory_size = max(real_memory_size,
 552                                        chunk->addr + chunk->size);
 553         }
 554
 555         /* Choose kernel address space layout: 2, 3, or 4 levels. */
 556 #ifdef CONFIG_64BIT
 557         vmalloc_size = VMALLOC_END ?: 128UL << 30;
 558         tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
 559         tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
 560         if (tmp <= (1UL << 42))
 561                 vmax = 1UL << 42;       /* 3-level kernel page table */
 562         else
 563                 vmax = 1UL << 53;       /* 4-level kernel page table */
 564 #else
 565         vmalloc_size = VMALLOC_END ?: 96UL << 20;
 566         vmax = 1UL << 31;               /* 2-level kernel page table */
 567 #endif
 568         /* vmalloc area is at the end of the kernel address space. */
 569         VMALLOC_END = vmax;
 570         VMALLOC_START = vmax - vmalloc_size;
 571
 572         /* Split remaining virtual space between 1:1 mapping & vmemmap array */
 573         tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
 574         tmp = VMALLOC_START - tmp * sizeof(struct page);
 575         tmp &= ~((vmax >> 11) - 1);     /* align to page table level */
 576         tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
 577         vmemmap = (struct page *) tmp;
 578
 579         /* Take care that memory_end is set and <= vmemmap */
 580         memory_end = min(memory_end ?: real_memory_size, tmp);
 581
 582         /* Fixup memory chunk array to fit into 0..memory_end */
 583         for (i = 0; i < MEMORY_CHUNKS; i++) {
 584                 struct mem_chunk *chunk = &memory_chunk[i];
 585
 586                 if (chunk->addr >= memory_end) {
 587                         memset(chunk, 0, sizeof(*chunk));
 588                         continue;
 589                 }
 590                 if (chunk->addr + chunk->size > memory_end)
 591                         chunk->size = memory_end - chunk->addr;
 592         }
 593 }
 594
 595 static void __init setup_vmcoreinfo(void)
 596 {
 597 #ifdef CONFIG_KEXEC
 598         unsigned long ptr = paddr_vmcoreinfo_note();
 599
 600         copy_to_absolute_zero(&S390_lowcore.vmcore_info, &ptr, sizeof(ptr));
 601 #endif
 602 }
 603
 604 #ifdef CONFIG_CRASH_DUMP
 605
 606 /*
 607  * Find suitable location for crashkernel memory
 608  */
 609 static unsigned long __init find_crash_base(unsigned long crash_size,
 610                                             char **msg)
 611 {
 612         unsigned long crash_base;
 613         struct mem_chunk *chunk;
 614         int i;
 615
 616         if (memory_chunk[0].size < crash_size) {
 617                 *msg = "first memory chunk must be at least crashkernel size";
 618                 return 0;
 619         }
 620         if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
 621                 return OLDMEM_BASE;
 622
 623         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
 624                 chunk = &memory_chunk[i];
 625                 if (chunk->size == 0)
 626                         continue;
 627                 if (chunk->type != CHUNK_READ_WRITE)
 628                         continue;
 629                 if (chunk->size < crash_size)
 630                         continue;
 631                 crash_base = (chunk->addr + chunk->size) - crash_size;
 632                 if (crash_base < crash_size)
 633                         continue;
 634                 if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
 635                         continue;
 636                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 637                         continue;
 638                 return crash_base;
 639         }
 640         *msg = "no suitable area found";
 641         return 0;
 642 }
 643
 644 /*
 645  * Check if crash_base and crash_size is valid
 646  */
 647 static int __init verify_crash_base(unsigned long crash_base,
 648                                     unsigned long crash_size,
 649                                     char **msg)
 650 {
 651         struct mem_chunk *chunk;
 652         int i;
 653
 654         /*
 655          * Because we do the swap to zero, we must have at least 'crash_size'
 656          * bytes free space before crash_base
 657          */
 658         if (crash_size > crash_base) {
 659                 *msg = "crashkernel offset must be greater than size";
 660                 return -EINVAL;
 661         }
 662
 663         /* First memory chunk must be at least crash_size */
 664         if (memory_chunk[0].size < crash_size) {
 665                 *msg = "first memory chunk must be at least crashkernel size";
 666                 return -EINVAL;
 667         }
 668         /* Check if we fit into the respective memory chunk */
 669         for (i = 0; i < MEMORY_CHUNKS; i++) {
 670                 chunk = &memory_chunk[i];
 671                 if (chunk->size == 0)
 672                         continue;
 673                 if (crash_base < chunk->addr)
 674                         continue;
 675                 if (crash_base >= chunk->addr + chunk->size)
 676                         continue;
 677                 /* we have found the memory chunk */
 678                 if (crash_base + crash_size > chunk->addr + chunk->size) {
 679                         *msg = "selected memory chunk is too small for "
 680                                 "crashkernel memory";
 681                         return -EINVAL;
 682                 }
 683                 return 0;
 684         }
 685         *msg = "invalid memory range specified";
 686         return -EINVAL;
 687 }
 688
 689 /*
 690  * Reserve kdump memory by creating a memory hole in the mem_chunk array
 691  */
 692 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
 693                                          int type)
 694 {
 695         create_mem_hole(memory_chunk, addr, size, type);
 696 }
 697
 698 /*
 699  * When kdump is enabled, we have to ensure that no memory from
 700  * the area [0 - crashkernel memory size] and
 701  * [crashk_res.start - crashk_res.end] is set offline.
 702  */
 703 static int kdump_mem_notifier(struct notifier_block *nb,
 704                               unsigned long action, void *data)
 705 {
 706         struct memory_notify *arg = data;
 707
 708         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 709                 return NOTIFY_BAD;
 710         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 711                 return NOTIFY_OK;
 712         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 713                 return NOTIFY_OK;
 714         return NOTIFY_BAD;
 715 }
 716
 717 static struct notifier_block kdump_mem_nb = {
 718         .notifier_call = kdump_mem_notifier,
 719 };
 720
 721 #endif
 722
 723 /*
 724  * Make sure that oldmem, where the dump is stored, is protected
 725  */
 726 static void reserve_oldmem(void)
 727 {
 728 #ifdef CONFIG_CRASH_DUMP
 729         if (!OLDMEM_BASE)
 730                 return;
 731
 732         reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
 733         reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
 734                               CHUNK_OLDMEM);
 735         if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
 736                 saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
 737         else
 738                 saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
 739 #endif
 740 }
 741
 742 /*
 743  * Reserve memory for kdump kernel to be loaded with kexec
 744  */
 745 static void __init reserve_crashkernel(void)
 746 {
 747 #ifdef CONFIG_CRASH_DUMP
 748         unsigned long long crash_base, crash_size;
 749         char *msg = NULL;
 750         int rc;
 751
 752         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 753                                &crash_base);
 754         if (rc || crash_size == 0)
 755                 return;
 756         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 757         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 758         if (register_memory_notifier(&kdump_mem_nb))
 759                 return;
 760         if (!crash_base)
 761                 crash_base = find_crash_base(crash_size, &msg);
 762         if (!crash_base) {
 763                 pr_info("crashkernel reservation failed: %s\n", msg);
 764                 unregister_memory_notifier(&kdump_mem_nb);
 765                 return;
 766         }
 767         if (verify_crash_base(crash_base, crash_size, &msg)) {
 768                 pr_info("crashkernel reservation failed: %s\n", msg);
 769                 unregister_memory_notifier(&kdump_mem_nb);
 770                 return;
 771         }
 772         if (!OLDMEM_BASE && MACHINE_IS_VM)
 773                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 774         crashk_res.start = crash_base;
 775         crashk_res.end = crash_base + crash_size - 1;
 776         insert_resource(&iomem_resource, &crashk_res);
 777         reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
 778         pr_info("Reserving %lluMB of memory at %lluMB "
 779                 "for crashkernel (System RAM: %luMB)\n",
 780                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
 781         os_info_crashkernel_add(crash_base, crash_size);
 782 #endif
 783 }
 784
 785 static void __init setup_memory(void)
 786 {
 787         unsigned long bootmap_size;
 788         unsigned long start_pfn, end_pfn;
 789         int i;
 790
 791         /*
 792          * partially used pages are not usable - thus
 793          * we are rounding upwards:
 794          */
 795         start_pfn = PFN_UP(__pa(&_end));
 796         end_pfn = max_pfn = PFN_DOWN(memory_end);
 797
 798 #ifdef CONFIG_BLK_DEV_INITRD
 799         /*
 800          * Move the initrd in case the bitmap of the bootmem allocater
 801          * would overwrite it.
 802          */
 803
 804         if (INITRD_START && INITRD_SIZE) {
 805                 unsigned long bmap_size;
 806                 unsigned long start;
 807
 808                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 809                 bmap_size = PFN_PHYS(bmap_size);
 810
 811                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 812                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 813
 814 #ifdef CONFIG_CRASH_DUMP
 815                         if (OLDMEM_BASE) {
 816                                 /* Move initrd behind kdump oldmem */
 817                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
 818                                     start < OLDMEM_BASE + OLDMEM_SIZE)
 819                                         start = OLDMEM_BASE + OLDMEM_SIZE;
 820                         }
 821 #endif
 822                         if (start + INITRD_SIZE > memory_end) {
 823                                 pr_err("initrd extends beyond end of "
 824                                        "memory (0x%08lx > 0x%08lx) "
 825                                        "disabling initrd\n",
 826                                        start + INITRD_SIZE, memory_end);
 827                                 INITRD_START = INITRD_SIZE = 0;
 828                         } else {
 829                                 pr_info("Moving initrd (0x%08lx -> "
 830                                         "0x%08lx, size: %ld)\n",
 831                                         INITRD_START, start, INITRD_SIZE);
 832                                 memmove((void *) start, (void *) INITRD_START,
 833                                         INITRD_SIZE);
 834                                 INITRD_START = start;
 835                         }
 836                 }
 837         }
 838 #endif
 839
 840         /*
 841          * Initialize the boot-time allocator
 842          */
 843         bootmap_size = init_bootmem(start_pfn, end_pfn);
 844
 845         /*
 846          * Register RAM areas with the bootmem allocator.
 847          */
 848
 849         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 850                 unsigned long start_chunk, end_chunk, pfn;
 851
 852                 if (memory_chunk[i].type != CHUNK_READ_WRITE &&
 853                     memory_chunk[i].type != CHUNK_CRASHK)
 854                         continue;
 855                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 856                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 857                 end_chunk = min(end_chunk, end_pfn);
 858                 if (start_chunk >= end_chunk)
 859                         continue;
 860                 memblock_add_node(PFN_PHYS(start_chunk),
 861                                   PFN_PHYS(end_chunk - start_chunk), 0);
 862                 pfn = max(start_chunk, start_pfn);
 863                 for (; pfn < end_chunk; pfn++)
 864                         page_set_storage_key(PFN_PHYS(pfn),
 865                                              PAGE_DEFAULT_KEY, 0);
 866         }
 867
 868         psw_set_key(PAGE_DEFAULT_KEY);
 869
 870         free_bootmem_with_active_regions(0, max_pfn);
 871
 872         /*
 873          * Reserve memory used for lowcore/command line/kernel image.
 874          */
 875         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 876         reserve_bootmem((unsigned long)_stext,
 877                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 878                         BOOTMEM_DEFAULT);
 879         /*
 880          * Reserve the bootmem bitmap itself as well. We do this in two
 881          * steps (first step was init_bootmem()) because this catches
 882          * the (very unlikely) case of us accidentally initializing the
 883          * bootmem allocator with an invalid RAM area.
 884          */
 885         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 886                         BOOTMEM_DEFAULT);
 887
 888 #ifdef CONFIG_CRASH_DUMP
 889         if (crashk_res.start)
 890                 reserve_bootmem(crashk_res.start,
 891                                 crashk_res.end - crashk_res.start + 1,
 892                                 BOOTMEM_DEFAULT);
 893         if (is_kdump_kernel())
 894                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
 895                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
 896 #endif
 897 #ifdef CONFIG_BLK_DEV_INITRD
 898         if (INITRD_START && INITRD_SIZE) {
 899                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 900                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 901                                         BOOTMEM_DEFAULT);
 902                         initrd_start = INITRD_START;
 903                         initrd_end = initrd_start + INITRD_SIZE;
 904                 } else {
 905                         pr_err("initrd extends beyond end of "
 906                                "memory (0x%08lx > 0x%08lx) "
 907                                "disabling initrd\n",
 908                                initrd_start + INITRD_SIZE, memory_end);
 909                         initrd_start = initrd_end = 0;
 910                 }
 911         }
 912 #endif
 913 }
 914
 915 /*
 916  * Setup hardware capabilities.
 917  */
 918 static void __init setup_hwcaps(void)
 919 {
 920         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 921         struct cpuid cpu_id;
 922         int i;
 923
 924         /*
 925          * The store facility list bits numbers as found in the principles
 926          * of operation are numbered with bit 1UL<<31 as number 0 to
 927          * bit 1UL<<0 as number 31.
 928          *   Bit 0: instructions named N3, "backported" to esa-mode
 929          *   Bit 2: z/Architecture mode is active
 930          *   Bit 7: the store-facility-list-extended facility is installed
 931          *   Bit 17: the message-security assist is installed
 932          *   Bit 19: the long-displacement facility is installed
 933          *   Bit 21: the extended-immediate facility is installed
 934          *   Bit 22: extended-translation facility 3 is installed
 935          *   Bit 30: extended-translation facility 3 enhancement facility
 936          * These get translated to:
 937          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 938          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 939          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 940          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 941          */
 942         for (i = 0; i < 6; i++)
 943                 if (test_facility(stfl_bits[i]))
 944                         elf_hwcap |= 1UL << i;
 945
 946         if (test_facility(22) && test_facility(30))
 947                 elf_hwcap |= HWCAP_S390_ETF3EH;
 948
 949         /*
 950          * Check for additional facilities with store-facility-list-extended.
 951          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 952          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 953          * as stored by stfl, bits 32-xxx contain additional facilities.
 954          * How many facility words are stored depends on the number of
 955          * doublewords passed to the instruction. The additional facilities
 956          * are:
 957          *   Bit 42: decimal floating point facility is installed
 958          *   Bit 44: perform floating point operation facility is installed
 959          * translated to:
 960          *   HWCAP_S390_DFP bit 6 (42 && 44).
 961          */
 962         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 963                 elf_hwcap |= HWCAP_S390_DFP;
 964
 965         /*
 966          * Huge page support HWCAP_S390_HPAGE is bit 7.
 967          */
 968         if (MACHINE_HAS_HPAGE)
 969                 elf_hwcap |= HWCAP_S390_HPAGE;
 970
 971         /*
 972          * 64-bit register support for 31-bit processes
 973          * HWCAP_S390_HIGH_GPRS is bit 9.
 974          */
 975         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 976
 977         get_cpu_id(&cpu_id);
 978         switch (cpu_id.machine) {
 979         case 0x9672:
 980 #if !defined(CONFIG_64BIT)
 981         default:        /* Use "g5" as default for 31 bit kernels. */
 982 #endif
 983                 strcpy(elf_platform, "g5");
 984                 break;
 985         case 0x2064:
 986         case 0x2066:
 987 #if defined(CONFIG_64BIT)
 988         default:        /* Use "z900" as default for 64 bit kernels. */
 989 #endif
 990                 strcpy(elf_platform, "z900");
 991                 break;
 992         case 0x2084:
 993         case 0x2086:
 994                 strcpy(elf_platform, "z990");
 995                 break;
 996         case 0x2094:
 997         case 0x2096:
 998                 strcpy(elf_platform, "z9-109");
 999                 break;
1000         case 0x2097:
1001         case 0x2098:
1002                 strcpy(elf_platform, "z10");
1003                 break;
1004         case 0x2817:
1005         case 0x2818:
1006                 strcpy(elf_platform, "z196");
1007                 break;
1008         }
1009 }
1010
1011 /*
1012  * Setup function called from init/main.c just after the banner
1013  * was printed.
1014  */
1015
1016 void __init setup_arch(char **cmdline_p)
1017 {
1018         /*
1019          * print what head.S has found out about the machine
1020          */
1021 #ifndef CONFIG_64BIT
1022         if (MACHINE_IS_VM)
1023                 pr_info("Linux is running as a z/VM "
1024                         "guest operating system in 31-bit mode\n");
1025         else if (MACHINE_IS_LPAR)
1026                 pr_info("Linux is running natively in 31-bit mode\n");
1027         if (MACHINE_HAS_IEEE)
1028                 pr_info("The hardware system has IEEE compatible "
1029                         "floating point units\n");
1030         else
1031                 pr_info("The hardware system has no IEEE compatible "
1032                         "floating point units\n");
1033 #else /* CONFIG_64BIT */
1034         if (MACHINE_IS_VM)
1035                 pr_info("Linux is running as a z/VM "
1036                         "guest operating system in 64-bit mode\n");
1037         else if (MACHINE_IS_KVM)
1038                 pr_info("Linux is running under KVM in 64-bit mode\n");
1039         else if (MACHINE_IS_LPAR)
1040                 pr_info("Linux is running natively in 64-bit mode\n");
1041 #endif /* CONFIG_64BIT */
1042
1043         /* Have one command line that is parsed and saved in /proc/cmdline */
1044         /* boot_command_line has been already set up in early.c */
1045         *cmdline_p = boot_command_line;
1046
1047         ROOT_DEV = Root_RAM0;
1048
1049         init_mm.start_code = PAGE_OFFSET;
1050         init_mm.end_code = (unsigned long) &_etext;
1051         init_mm.end_data = (unsigned long) &_edata;
1052         init_mm.brk = (unsigned long) &_end;
1053
1054         if (MACHINE_HAS_MVCOS)
1055                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1056         else
1057                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1058
1059         parse_early_param();
1060
1061         os_info_init();
1062         setup_ipl();
1063         setup_memory_end();
1064         setup_addressing_mode();
1065         reserve_oldmem();
1066         reserve_crashkernel();
1067         setup_memory();
1068         setup_resources();
1069         setup_vmcoreinfo();
1070         setup_lowcore();
1071
1072         cpu_init();
1073         s390_init_cpu_topology();
1074
1075         /*
1076          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1077          */
1078         setup_hwcaps();
1079
1080         /*
1081          * Create kernel page tables and switch to virtual addressing.
1082          */
1083         paging_init();
1084
1085         /* Setup default console */
1086         conmode_default();
1087         set_preferred_console();
1088
1089         /* Setup zfcpdump support */
1090         setup_zfcpdump(console_devno);
1091 }