arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) IBM Corp. 1999,2010
   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 /*
 106  * condev= and conmode= setup parameter.
 107  */
 108
 109 static int __init condev_setup(char *str)
 110 {
 111         int vdev;
 112
 113         vdev = simple_strtoul(str, &str, 0);
 114         if (vdev >= 0 && vdev < 65536) {
 115                 console_devno = vdev;
 116                 console_irq = -1;
 117         }
 118         return 1;
 119 }
 120
 121 __setup("condev=", condev_setup);
 122
 123 static void __init set_preferred_console(void)
 124 {
 125         if (MACHINE_IS_KVM)
 126                 add_preferred_console("hvc", 0, NULL);
 127         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 128                 add_preferred_console("ttyS", 0, NULL);
 129         else if (CONSOLE_IS_3270)
 130                 add_preferred_console("tty3270", 0, NULL);
 131 }
 132
 133 static int __init conmode_setup(char *str)
 134 {
 135 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 136         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 137                 SET_CONSOLE_SCLP;
 138 #endif
 139 #if defined(CONFIG_TN3215_CONSOLE)
 140         if (strncmp(str, "3215", 5) == 0)
 141                 SET_CONSOLE_3215;
 142 #endif
 143 #if defined(CONFIG_TN3270_CONSOLE)
 144         if (strncmp(str, "3270", 5) == 0)
 145                 SET_CONSOLE_3270;
 146 #endif
 147         set_preferred_console();
 148         return 1;
 149 }
 150
 151 __setup("conmode=", conmode_setup);
 152
 153 static void __init conmode_default(void)
 154 {
 155         char query_buffer[1024];
 156         char *ptr;
 157
 158         if (MACHINE_IS_VM) {
 159                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 160                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 161                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 162                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 163                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 164                 ptr = strstr(query_buffer, "CONMODE");
 165                 /*
 166                  * Set the conmode to 3215 so that the device recognition
 167                  * will set the cu_type of the console to 3215. If the
 168                  * conmode is 3270 and we don't set it back then both
 169                  * 3215 and the 3270 driver will try to access the console
 170                  * device (3215 as console and 3270 as normal tty).
 171                  */
 172                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 173                 if (ptr == NULL) {
 174 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 175                         SET_CONSOLE_SCLP;
 176 #endif
 177                         return;
 178                 }
 179                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 180 #if defined(CONFIG_TN3270_CONSOLE)
 181                         SET_CONSOLE_3270;
 182 #elif defined(CONFIG_TN3215_CONSOLE)
 183                         SET_CONSOLE_3215;
 184 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 185                         SET_CONSOLE_SCLP;
 186 #endif
 187                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 188 #if defined(CONFIG_TN3215_CONSOLE)
 189                         SET_CONSOLE_3215;
 190 #elif defined(CONFIG_TN3270_CONSOLE)
 191                         SET_CONSOLE_3270;
 192 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 193                         SET_CONSOLE_SCLP;
 194 #endif
 195                 }
 196         } else {
 197 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 198                 SET_CONSOLE_SCLP;
 199 #endif
 200         }
 201 }
 202
 203 #ifdef CONFIG_ZFCPDUMP
 204 static void __init setup_zfcpdump(unsigned int console_devno)
 205 {
 206         static char str[41];
 207
 208         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 209                 return;
 210         if (console_devno != -1)
 211                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 212                         ipl_info.data.fcp.dev_id.devno, console_devno);
 213         else
 214                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 215                         ipl_info.data.fcp.dev_id.devno);
 216         strcat(boot_command_line, str);
 217         console_loglevel = 2;
 218 }
 219 #else
 220 static inline void setup_zfcpdump(unsigned int console_devno) {}
 221 #endif /* CONFIG_ZFCPDUMP */
 222
 223  /*
 224  * Reboot, halt and power_off stubs. They just call _machine_restart,
 225  * _machine_halt or _machine_power_off.
 226  */
 227
 228 void machine_restart(char *command)
 229 {
 230         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 231                 /*
 232                  * Only unblank the console if we are called in enabled
 233                  * context or a bust_spinlocks cleared the way for us.
 234                  */
 235                 console_unblank();
 236         _machine_restart(command);
 237 }
 238
 239 void machine_halt(void)
 240 {
 241         if (!in_interrupt() || oops_in_progress)
 242                 /*
 243                  * Only unblank the console if we are called in enabled
 244                  * context or a bust_spinlocks cleared the way for us.
 245                  */
 246                 console_unblank();
 247         _machine_halt();
 248 }
 249
 250 void machine_power_off(void)
 251 {
 252         if (!in_interrupt() || oops_in_progress)
 253                 /*
 254                  * Only unblank the console if we are called in enabled
 255                  * context or a bust_spinlocks cleared the way for us.
 256                  */
 257                 console_unblank();
 258         _machine_power_off();
 259 }
 260
 261 /*
 262  * Dummy power off function.
 263  */
 264 void (*pm_power_off)(void) = machine_power_off;
 265
 266 static int __init early_parse_mem(char *p)
 267 {
 268         memory_end = memparse(p, &p);
 269         memory_end_set = 1;
 270         return 0;
 271 }
 272 early_param("mem", early_parse_mem);
 273
 274 unsigned int user_mode = HOME_SPACE_MODE;
 275 EXPORT_SYMBOL_GPL(user_mode);
 276
 277 static int set_amode_and_uaccess(unsigned long user_amode,
 278                                  unsigned long user32_amode)
 279 {
 280         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 281                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 282                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 283 #ifdef CONFIG_COMPAT
 284         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 285                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 286                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 287         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 288                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 289                           PSW32_MASK_PSTATE;
 290 #endif
 291         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 292                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 293
 294         if (MACHINE_HAS_MVCOS) {
 295                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 296                 return 1;
 297         } else {
 298                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 299                 return 0;
 300         }
 301 }
 302
 303 /*
 304  * Switch kernel/user addressing modes?
 305  */
 306 static int __init early_parse_switch_amode(char *p)
 307 {
 308         user_mode = PRIMARY_SPACE_MODE;
 309         return 0;
 310 }
 311 early_param("switch_amode", early_parse_switch_amode);
 312
 313 static int __init early_parse_user_mode(char *p)
 314 {
 315         if (p && strcmp(p, "primary") == 0)
 316                 user_mode = PRIMARY_SPACE_MODE;
 317         else if (!p || strcmp(p, "home") == 0)
 318                 user_mode = HOME_SPACE_MODE;
 319         else
 320                 return 1;
 321         return 0;
 322 }
 323 early_param("user_mode", early_parse_user_mode);
 324
 325 static void setup_addressing_mode(void)
 326 {
 327         if (user_mode == PRIMARY_SPACE_MODE) {
 328                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 329                         pr_info("Address spaces switched, "
 330                                 "mvcos available\n");
 331                 else
 332                         pr_info("Address spaces switched, "
 333                                 "mvcos not available\n");
 334         }
 335 }
 336
 337 static void __init
 338 setup_lowcore(void)
 339 {
 340         struct _lowcore *lc;
 341
 342         /*
 343          * Setup lowcore for boot cpu
 344          */
 345         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 346         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 347         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 348         lc->restart_psw.addr =
 349                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 350         if (user_mode != HOME_SPACE_MODE)
 351                 lc->restart_psw.mask |= PSW_ASC_HOME;
 352         lc->external_new_psw.mask = psw_kernel_bits;
 353         lc->external_new_psw.addr =
 354                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 355         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 356         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 357         lc->program_new_psw.mask = psw_kernel_bits;
 358         lc->program_new_psw.addr =
 359                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 360         lc->mcck_new_psw.mask =
 361                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 362         lc->mcck_new_psw.addr =
 363                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 364         lc->io_new_psw.mask = psw_kernel_bits;
 365         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 366         lc->clock_comparator = -1ULL;
 367         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 368         lc->async_stack = (unsigned long)
 369                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 370         lc->panic_stack = (unsigned long)
 371                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 372         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 373         lc->thread_info = (unsigned long) &init_thread_union;
 374         lc->machine_flags = S390_lowcore.machine_flags;
 375         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 376         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 377                MAX_FACILITY_BIT/8);
 378 #ifndef CONFIG_64BIT
 379         if (MACHINE_HAS_IEEE) {
 380                 lc->extended_save_area_addr = (__u32)
 381                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 382                 /* enable extended save area */
 383                 __ctl_set_bit(14, 29);
 384         }
 385 #else
 386         lc->cmf_hpp = -1ULL;
 387         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 388 #endif
 389         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 390         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 391         lc->exit_timer = S390_lowcore.exit_timer;
 392         lc->user_timer = S390_lowcore.user_timer;
 393         lc->system_timer = S390_lowcore.system_timer;
 394         lc->steal_timer = S390_lowcore.steal_timer;
 395         lc->last_update_timer = S390_lowcore.last_update_timer;
 396         lc->last_update_clock = S390_lowcore.last_update_clock;
 397         lc->ftrace_func = S390_lowcore.ftrace_func;
 398         set_prefix((u32)(unsigned long) lc);
 399         lowcore_ptr[0] = lc;
 400 }
 401
 402 static struct resource code_resource = {
 403         .name  = "Kernel code",
 404         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 405 };
 406
 407 static struct resource data_resource = {
 408         .name = "Kernel data",
 409         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 410 };
 411
 412 static struct resource bss_resource = {
 413         .name = "Kernel bss",
 414         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 415 };
 416
 417 static struct resource __initdata *standard_resources[] = {
 418         &code_resource,
 419         &data_resource,
 420         &bss_resource,
 421 };
 422
 423 static void __init setup_resources(void)
 424 {
 425         struct resource *res, *std_res, *sub_res;
 426         int i, j;
 427
 428         code_resource.start = (unsigned long) &_text;
 429         code_resource.end = (unsigned long) &_etext - 1;
 430         data_resource.start = (unsigned long) &_etext;
 431         data_resource.end = (unsigned long) &_edata - 1;
 432         bss_resource.start = (unsigned long) &__bss_start;
 433         bss_resource.end = (unsigned long) &__bss_stop - 1;
 434
 435         for (i = 0; i < MEMORY_CHUNKS; i++) {
 436                 if (!memory_chunk[i].size)
 437                         continue;
 438                 res = alloc_bootmem_low(sizeof(*res));
 439                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 440                 switch (memory_chunk[i].type) {
 441                 case CHUNK_READ_WRITE:
 442                         res->name = "System RAM";
 443                         break;
 444                 case CHUNK_READ_ONLY:
 445                         res->name = "System ROM";
 446                         res->flags |= IORESOURCE_READONLY;
 447                         break;
 448                 default:
 449                         res->name = "reserved";
 450                 }
 451                 res->start = memory_chunk[i].addr;
 452                 res->end = res->start + memory_chunk[i].size - 1;
 453                 request_resource(&iomem_resource, res);
 454
 455                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 456                         std_res = standard_resources[j];
 457                         if (std_res->start < res->start ||
 458                             std_res->start > res->end)
 459                                 continue;
 460                         if (std_res->end > res->end) {
 461                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 462                                 *sub_res = *std_res;
 463                                 sub_res->end = res->end;
 464                                 std_res->start = res->end + 1;
 465                                 request_resource(res, sub_res);
 466                         } else {
 467                                 request_resource(res, std_res);
 468                         }
 469                 }
 470         }
 471 }
 472
 473 unsigned long real_memory_size;
 474 EXPORT_SYMBOL_GPL(real_memory_size);
 475
 476 static void __init setup_memory_end(void)
 477 {
 478         unsigned long memory_size;
 479         unsigned long max_mem;
 480         int i;
 481
 482 #ifdef CONFIG_ZFCPDUMP
 483         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
 484                 memory_end = ZFCPDUMP_HSA_SIZE;
 485                 memory_end_set = 1;
 486         }
 487 #endif
 488         memory_size = 0;
 489         memory_end &= PAGE_MASK;
 490
 491         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 492         memory_end = min(max_mem, memory_end);
 493
 494         /*
 495          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 496          * extra checks that HOLES_IN_ZONE would require.
 497          */
 498         for (i = 0; i < MEMORY_CHUNKS; i++) {
 499                 unsigned long start, end;
 500                 struct mem_chunk *chunk;
 501                 unsigned long align;
 502
 503                 chunk = &memory_chunk[i];
 504                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 505                 start = (chunk->addr + align - 1) & ~(align - 1);
 506                 end = (chunk->addr + chunk->size) & ~(align - 1);
 507                 if (start >= end)
 508                         memset(chunk, 0, sizeof(*chunk));
 509                 else {
 510                         chunk->addr = start;
 511                         chunk->size = end - start;
 512                 }
 513         }
 514
 515         for (i = 0; i < MEMORY_CHUNKS; i++) {
 516                 struct mem_chunk *chunk = &memory_chunk[i];
 517
 518                 real_memory_size = max(real_memory_size,
 519                                        chunk->addr + chunk->size);
 520                 if (chunk->addr >= max_mem) {
 521                         memset(chunk, 0, sizeof(*chunk));
 522                         continue;
 523                 }
 524                 if (chunk->addr + chunk->size > max_mem)
 525                         chunk->size = max_mem - chunk->addr;
 526                 memory_size = max(memory_size, chunk->addr + chunk->size);
 527         }
 528         if (!memory_end)
 529                 memory_end = memory_size;
 530 }
 531
 532 static void __init
 533 setup_memory(void)
 534 {
 535         unsigned long bootmap_size;
 536         unsigned long start_pfn, end_pfn;
 537         int i;
 538
 539         /*
 540          * partially used pages are not usable - thus
 541          * we are rounding upwards:
 542          */
 543         start_pfn = PFN_UP(__pa(&_end));
 544         end_pfn = max_pfn = PFN_DOWN(memory_end);
 545
 546 #ifdef CONFIG_BLK_DEV_INITRD
 547         /*
 548          * Move the initrd in case the bitmap of the bootmem allocater
 549          * would overwrite it.
 550          */
 551
 552         if (INITRD_START && INITRD_SIZE) {
 553                 unsigned long bmap_size;
 554                 unsigned long start;
 555
 556                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 557                 bmap_size = PFN_PHYS(bmap_size);
 558
 559                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 560                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 561
 562                         if (start + INITRD_SIZE > memory_end) {
 563                                 pr_err("initrd extends beyond end of "
 564                                        "memory (0x%08lx > 0x%08lx) "
 565                                        "disabling initrd\n",
 566                                        start + INITRD_SIZE, memory_end);
 567                                 INITRD_START = INITRD_SIZE = 0;
 568                         } else {
 569                                 pr_info("Moving initrd (0x%08lx -> "
 570                                         "0x%08lx, size: %ld)\n",
 571                                         INITRD_START, start, INITRD_SIZE);
 572                                 memmove((void *) start, (void *) INITRD_START,
 573                                         INITRD_SIZE);
 574                                 INITRD_START = start;
 575                         }
 576                 }
 577         }
 578 #endif
 579
 580         /*
 581          * Initialize the boot-time allocator
 582          */
 583         bootmap_size = init_bootmem(start_pfn, end_pfn);
 584
 585         /*
 586          * Register RAM areas with the bootmem allocator.
 587          */
 588
 589         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 590                 unsigned long start_chunk, end_chunk, pfn;
 591
 592                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 593                         continue;
 594                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 595                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 596                 end_chunk = min(end_chunk, end_pfn);
 597                 if (start_chunk >= end_chunk)
 598                         continue;
 599                 add_active_range(0, start_chunk, end_chunk);
 600                 pfn = max(start_chunk, start_pfn);
 601                 for (; pfn < end_chunk; pfn++)
 602                         page_set_storage_key(PFN_PHYS(pfn),
 603                                              PAGE_DEFAULT_KEY, 0);
 604         }
 605
 606         psw_set_key(PAGE_DEFAULT_KEY);
 607
 608         free_bootmem_with_active_regions(0, max_pfn);
 609
 610         /*
 611          * Reserve memory used for lowcore/command line/kernel image.
 612          */
 613         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 614         reserve_bootmem((unsigned long)_stext,
 615                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 616                         BOOTMEM_DEFAULT);
 617         /*
 618          * Reserve the bootmem bitmap itself as well. We do this in two
 619          * steps (first step was init_bootmem()) because this catches
 620          * the (very unlikely) case of us accidentally initializing the
 621          * bootmem allocator with an invalid RAM area.
 622          */
 623         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 624                         BOOTMEM_DEFAULT);
 625
 626 #ifdef CONFIG_BLK_DEV_INITRD
 627         if (INITRD_START && INITRD_SIZE) {
 628                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 629                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 630                                         BOOTMEM_DEFAULT);
 631                         initrd_start = INITRD_START;
 632                         initrd_end = initrd_start + INITRD_SIZE;
 633                 } else {
 634                         pr_err("initrd extends beyond end of "
 635                                "memory (0x%08lx > 0x%08lx) "
 636                                "disabling initrd\n",
 637                                initrd_start + INITRD_SIZE, memory_end);
 638                         initrd_start = initrd_end = 0;
 639                 }
 640         }
 641 #endif
 642 }
 643
 644 /*
 645  * Setup hardware capabilities.
 646  */
 647 static void __init setup_hwcaps(void)
 648 {
 649         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 650         struct cpuid cpu_id;
 651         int i;
 652
 653         /*
 654          * The store facility list bits numbers as found in the principles
 655          * of operation are numbered with bit 1UL<<31 as number 0 to
 656          * bit 1UL<<0 as number 31.
 657          *   Bit 0: instructions named N3, "backported" to esa-mode
 658          *   Bit 2: z/Architecture mode is active
 659          *   Bit 7: the store-facility-list-extended facility is installed
 660          *   Bit 17: the message-security assist is installed
 661          *   Bit 19: the long-displacement facility is installed
 662          *   Bit 21: the extended-immediate facility is installed
 663          *   Bit 22: extended-translation facility 3 is installed
 664          *   Bit 30: extended-translation facility 3 enhancement facility
 665          * These get translated to:
 666          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 667          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 668          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 669          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 670          */
 671         for (i = 0; i < 6; i++)
 672                 if (test_facility(stfl_bits[i]))
 673                         elf_hwcap |= 1UL << i;
 674
 675         if (test_facility(22) && test_facility(30))
 676                 elf_hwcap |= HWCAP_S390_ETF3EH;
 677
 678         /*
 679          * Check for additional facilities with store-facility-list-extended.
 680          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 681          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 682          * as stored by stfl, bits 32-xxx contain additional facilities.
 683          * How many facility words are stored depends on the number of
 684          * doublewords passed to the instruction. The additional facilities
 685          * are:
 686          *   Bit 42: decimal floating point facility is installed
 687          *   Bit 44: perform floating point operation facility is installed
 688          * translated to:
 689          *   HWCAP_S390_DFP bit 6 (42 && 44).
 690          */
 691         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 692                 elf_hwcap |= HWCAP_S390_DFP;
 693
 694         /*
 695          * Huge page support HWCAP_S390_HPAGE is bit 7.
 696          */
 697         if (MACHINE_HAS_HPAGE)
 698                 elf_hwcap |= HWCAP_S390_HPAGE;
 699
 700         /*
 701          * 64-bit register support for 31-bit processes
 702          * HWCAP_S390_HIGH_GPRS is bit 9.
 703          */
 704         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 705
 706         get_cpu_id(&cpu_id);
 707         switch (cpu_id.machine) {
 708         case 0x9672:
 709 #if !defined(CONFIG_64BIT)
 710         default:        /* Use "g5" as default for 31 bit kernels. */
 711 #endif
 712                 strcpy(elf_platform, "g5");
 713                 break;
 714         case 0x2064:
 715         case 0x2066:
 716 #if defined(CONFIG_64BIT)
 717         default:        /* Use "z900" as default for 64 bit kernels. */
 718 #endif
 719                 strcpy(elf_platform, "z900");
 720                 break;
 721         case 0x2084:
 722         case 0x2086:
 723                 strcpy(elf_platform, "z990");
 724                 break;
 725         case 0x2094:
 726         case 0x2096:
 727                 strcpy(elf_platform, "z9-109");
 728                 break;
 729         case 0x2097:
 730         case 0x2098:
 731                 strcpy(elf_platform, "z10");
 732                 break;
 733         case 0x2817:
 734                 strcpy(elf_platform, "z196");
 735                 break;
 736         }
 737 }
 738
 739 /*
 740  * Setup function called from init/main.c just after the banner
 741  * was printed.
 742  */
 743
 744 void __init
 745 setup_arch(char **cmdline_p)
 746 {
 747         /*
 748          * print what head.S has found out about the machine
 749          */
 750 #ifndef CONFIG_64BIT
 751         if (MACHINE_IS_VM)
 752                 pr_info("Linux is running as a z/VM "
 753                         "guest operating system in 31-bit mode\n");
 754         else if (MACHINE_IS_LPAR)
 755                 pr_info("Linux is running natively in 31-bit mode\n");
 756         if (MACHINE_HAS_IEEE)
 757                 pr_info("The hardware system has IEEE compatible "
 758                         "floating point units\n");
 759         else
 760                 pr_info("The hardware system has no IEEE compatible "
 761                         "floating point units\n");
 762 #else /* CONFIG_64BIT */
 763         if (MACHINE_IS_VM)
 764                 pr_info("Linux is running as a z/VM "
 765                         "guest operating system in 64-bit mode\n");
 766         else if (MACHINE_IS_KVM)
 767                 pr_info("Linux is running under KVM in 64-bit mode\n");
 768         else if (MACHINE_IS_LPAR)
 769                 pr_info("Linux is running natively in 64-bit mode\n");
 770 #endif /* CONFIG_64BIT */
 771
 772         /* Have one command line that is parsed and saved in /proc/cmdline */
 773         /* boot_command_line has been already set up in early.c */
 774         *cmdline_p = boot_command_line;
 775
 776         ROOT_DEV = Root_RAM0;
 777
 778         init_mm.start_code = PAGE_OFFSET;
 779         init_mm.end_code = (unsigned long) &_etext;
 780         init_mm.end_data = (unsigned long) &_edata;
 781         init_mm.brk = (unsigned long) &_end;
 782
 783         if (MACHINE_HAS_MVCOS)
 784                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
 785         else
 786                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 787
 788         parse_early_param();
 789
 790         setup_ipl();
 791         setup_memory_end();
 792         setup_addressing_mode();
 793         setup_memory();
 794         setup_resources();
 795         setup_lowcore();
 796
 797         cpu_init();
 798         s390_init_cpu_topology();
 799
 800         /*
 801          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
 802          */
 803         setup_hwcaps();
 804
 805         /*
 806          * Create kernel page tables and switch to virtual addressing.
 807          */
 808         paging_init();
 809
 810         /* Setup default console */
 811         conmode_default();
 812         set_preferred_console();
 813
 814         /* Setup zfcpdump support */
 815         setup_zfcpdump(console_devno);
 816 }