arch/s390/kernel/setup.c

   1 /*
   2  *  arch/s390/kernel/setup.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "arch/i386/kernel/setup.c"
  10  *    Copyright (C) 1995, Linus Torvalds
  11  */
  12
  13 /*
  14  * This file handles the architecture-dependent parts of initialization
  15  */
  16
  17 #define KMSG_COMPONENT "setup"
  18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  19
  20 #include <linux/errno.h>
  21 #include <linux/module.h>
  22 #include <linux/sched.h>
  23 #include <linux/kernel.h>
  24 #include <linux/mm.h>
  25 #include <linux/stddef.h>
  26 #include <linux/unistd.h>
  27 #include <linux/ptrace.h>
  28 #include <linux/slab.h>
  29 #include <linux/user.h>
  30 #include <linux/tty.h>
  31 #include <linux/ioport.h>
  32 #include <linux/delay.h>
  33 #include <linux/init.h>
  34 #include <linux/initrd.h>
  35 #include <linux/bootmem.h>
  36 #include <linux/root_dev.h>
  37 #include <linux/console.h>
  38 #include <linux/kernel_stat.h>
  39 #include <linux/device.h>
  40 #include <linux/notifier.h>
  41 #include <linux/pfn.h>
  42 #include <linux/ctype.h>
  43 #include <linux/reboot.h>
  44 #include <linux/topology.h>
  45
  46 #include <asm/ipl.h>
  47 #include <asm/uaccess.h>
  48 #include <asm/system.h>
  49 #include <asm/smp.h>
  50 #include <asm/mmu_context.h>
  51 #include <asm/cpcmd.h>
  52 #include <asm/lowcore.h>
  53 #include <asm/irq.h>
  54 #include <asm/page.h>
  55 #include <asm/ptrace.h>
  56 #include <asm/sections.h>
  57 #include <asm/ebcdic.h>
  58 #include <asm/compat.h>
  59 #include <asm/kvm_virtio.h>
  60
  61 long psw_kernel_bits    = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
  62                            PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
  63 long psw_user_bits      = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
  64                            PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
  65                            PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
  66
  67 /*
  68  * User copy operations.
  69  */
  70 struct uaccess_ops uaccess;
  71 EXPORT_SYMBOL(uaccess);
  72
  73 /*
  74  * Machine setup..
  75  */
  76 unsigned int console_mode = 0;
  77 unsigned int console_devno = -1;
  78 unsigned int console_irq = -1;
  79 unsigned long machine_flags;
  80 unsigned long elf_hwcap = 0;
  81 char elf_platform[ELF_PLATFORM_SIZE];
  82
  83 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  84 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
  85 static unsigned long __initdata memory_end;
  86
  87 /*
  88  * This is set up by the setup-routine at boot-time
  89  * for S390 need to find out, what we have to setup
  90  * using address 0x10400 ...
  91  */
  92
  93 #include <asm/setup.h>
  94
  95 static struct resource code_resource = {
  96         .name  = "Kernel code",
  97         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
  98 };
  99
 100 static struct resource data_resource = {
 101         .name = "Kernel data",
 102         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 103 };
 104
 105 /*
 106  * cpu_init() initializes state that is per-CPU.
 107  */
 108 void __cpuinit cpu_init(void)
 109 {
 110         int addr = hard_smp_processor_id();
 111
 112         /*
 113          * Store processor id in lowcore (used e.g. in timer_interrupt)
 114          */
 115         get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
 116         S390_lowcore.cpu_data.cpu_addr = addr;
 117
 118         /*
 119          * Force FPU initialization:
 120          */
 121         clear_thread_flag(TIF_USEDFPU);
 122         clear_used_math();
 123
 124         atomic_inc(&init_mm.mm_count);
 125         current->active_mm = &init_mm;
 126         if (current->mm)
 127                 BUG();
 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 int __init conmode_setup(char *str)
 150 {
 151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 152         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 153                 SET_CONSOLE_SCLP;
 154 #endif
 155 #if defined(CONFIG_TN3215_CONSOLE)
 156         if (strncmp(str, "3215", 5) == 0)
 157                 SET_CONSOLE_3215;
 158 #endif
 159 #if defined(CONFIG_TN3270_CONSOLE)
 160         if (strncmp(str, "3270", 5) == 0)
 161                 SET_CONSOLE_3270;
 162 #endif
 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 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
 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 (console_devno != -1)
 226                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
 227                         ipl_info.data.fcp.dev_id.devno, console_devno);
 228         else
 229                 sprintf(str, " cio_ignore=all,!0.0.%04x",
 230                         ipl_info.data.fcp.dev_id.devno);
 231         strcat(boot_command_line, str);
 232         console_loglevel = 2;
 233 }
 234 #else
 235 static inline void setup_zfcpdump(unsigned int console_devno) {}
 236 #endif /* CONFIG_ZFCPDUMP */
 237
 238  /*
 239  * Reboot, halt and power_off stubs. They just call _machine_restart,
 240  * _machine_halt or _machine_power_off.
 241  */
 242
 243 void machine_restart(char *command)
 244 {
 245         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 246                 /*
 247                  * Only unblank the console if we are called in enabled
 248                  * context or a bust_spinlocks cleared the way for us.
 249                  */
 250                 console_unblank();
 251         _machine_restart(command);
 252 }
 253
 254 void machine_halt(void)
 255 {
 256         if (!in_interrupt() || 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_halt();
 263 }
 264
 265 void machine_power_off(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_power_off();
 274 }
 275
 276 /*
 277  * Dummy power off function.
 278  */
 279 void (*pm_power_off)(void) = machine_power_off;
 280
 281 static int __init early_parse_mem(char *p)
 282 {
 283         memory_end = memparse(p, &p);
 284         return 0;
 285 }
 286 early_param("mem", early_parse_mem);
 287
 288 #ifdef CONFIG_S390_SWITCH_AMODE
 289 #ifdef CONFIG_PGSTE
 290 unsigned int switch_amode = 1;
 291 #else
 292 unsigned int switch_amode = 0;
 293 #endif
 294 EXPORT_SYMBOL_GPL(switch_amode);
 295
 296 static int set_amode_and_uaccess(unsigned long user_amode,
 297                                  unsigned long user32_amode)
 298 {
 299         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
 300                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 301                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 302 #ifdef CONFIG_COMPAT
 303         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
 304                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
 305                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
 306         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
 307                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
 308                           PSW32_MASK_PSTATE;
 309 #endif
 310         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
 311                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
 312
 313         if (MACHINE_HAS_MVCOS) {
 314                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
 315                 return 1;
 316         } else {
 317                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
 318                 return 0;
 319         }
 320 }
 321
 322 /*
 323  * Switch kernel/user addressing modes?
 324  */
 325 static int __init early_parse_switch_amode(char *p)
 326 {
 327         switch_amode = 1;
 328         return 0;
 329 }
 330 early_param("switch_amode", early_parse_switch_amode);
 331
 332 #else /* CONFIG_S390_SWITCH_AMODE */
 333 static inline int set_amode_and_uaccess(unsigned long user_amode,
 334                                         unsigned long user32_amode)
 335 {
 336         return 0;
 337 }
 338 #endif /* CONFIG_S390_SWITCH_AMODE */
 339
 340 #ifdef CONFIG_S390_EXEC_PROTECT
 341 unsigned int s390_noexec = 0;
 342 EXPORT_SYMBOL_GPL(s390_noexec);
 343
 344 /*
 345  * Enable execute protection?
 346  */
 347 static int __init early_parse_noexec(char *p)
 348 {
 349         if (!strncmp(p, "off", 3))
 350                 return 0;
 351         switch_amode = 1;
 352         s390_noexec = 1;
 353         return 0;
 354 }
 355 early_param("noexec", early_parse_noexec);
 356 #endif /* CONFIG_S390_EXEC_PROTECT */
 357
 358 static void setup_addressing_mode(void)
 359 {
 360         if (s390_noexec) {
 361                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
 362                                           PSW32_ASC_SECONDARY))
 363                         pr_info("Execute protection active, "
 364                                 "mvcos available\n");
 365                 else
 366                         pr_info("Execute protection active, "
 367                                 "mvcos not available\n");
 368         } else if (switch_amode) {
 369                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
 370                         pr_info("Address spaces switched, "
 371                                 "mvcos available\n");
 372                 else
 373                         pr_info("Address spaces switched, "
 374                                 "mvcos not available\n");
 375         }
 376 #ifdef CONFIG_TRACE_IRQFLAGS
 377         sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 378         io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
 379 #endif
 380 }
 381
 382 static void __init
 383 setup_lowcore(void)
 384 {
 385         struct _lowcore *lc;
 386         int lc_pages;
 387
 388         /*
 389          * Setup lowcore for boot cpu
 390          */
 391         lc_pages = sizeof(void *) == 8 ? 2 : 1;
 392         lc = (struct _lowcore *)
 393                 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
 394         memset(lc, 0, lc_pages * PAGE_SIZE);
 395         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 396         lc->restart_psw.addr =
 397                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 398         if (switch_amode)
 399                 lc->restart_psw.mask |= PSW_ASC_HOME;
 400         lc->external_new_psw.mask = psw_kernel_bits;
 401         lc->external_new_psw.addr =
 402                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 403         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
 404         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 405         lc->program_new_psw.mask = psw_kernel_bits;
 406         lc->program_new_psw.addr =
 407                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
 408         lc->mcck_new_psw.mask =
 409                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
 410         lc->mcck_new_psw.addr =
 411                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 412         lc->io_new_psw.mask = psw_kernel_bits;
 413         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 414         lc->ipl_device = S390_lowcore.ipl_device;
 415         lc->clock_comparator = -1ULL;
 416         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
 417         lc->async_stack = (unsigned long)
 418                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
 419         lc->panic_stack = (unsigned long)
 420                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
 421         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 422         lc->thread_info = (unsigned long) &init_thread_union;
 423 #ifndef CONFIG_64BIT
 424         if (MACHINE_HAS_IEEE) {
 425                 lc->extended_save_area_addr = (__u32)
 426                         __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
 427                 /* enable extended save area */
 428                 __ctl_set_bit(14, 29);
 429         }
 430 #endif
 431         set_prefix((u32)(unsigned long) lc);
 432 }
 433
 434 static void __init
 435 setup_resources(void)
 436 {
 437         struct resource *res, *sub_res;
 438         int i;
 439
 440         code_resource.start = (unsigned long) &_text;
 441         code_resource.end = (unsigned long) &_etext - 1;
 442         data_resource.start = (unsigned long) &_etext;
 443         data_resource.end = (unsigned long) &_edata - 1;
 444
 445         for (i = 0; i < MEMORY_CHUNKS; i++) {
 446                 if (!memory_chunk[i].size)
 447                         continue;
 448                 res = alloc_bootmem_low(sizeof(struct resource));
 449                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 450                 switch (memory_chunk[i].type) {
 451                 case CHUNK_READ_WRITE:
 452                         res->name = "System RAM";
 453                         break;
 454                 case CHUNK_READ_ONLY:
 455                         res->name = "System ROM";
 456                         res->flags |= IORESOURCE_READONLY;
 457                         break;
 458                 default:
 459                         res->name = "reserved";
 460                 }
 461                 res->start = memory_chunk[i].addr;
 462                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
 463                 request_resource(&iomem_resource, res);
 464
 465                 if (code_resource.start >= res->start  &&
 466                         code_resource.start <= res->end &&
 467                         code_resource.end > res->end) {
 468                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 469                         memcpy(sub_res, &code_resource,
 470                                 sizeof(struct resource));
 471                         sub_res->end = res->end;
 472                         code_resource.start = res->end + 1;
 473                         request_resource(res, sub_res);
 474                 }
 475
 476                 if (code_resource.start >= res->start &&
 477                         code_resource.start <= res->end &&
 478                         code_resource.end <= res->end)
 479                         request_resource(res, &code_resource);
 480
 481                 if (data_resource.start >= res->start &&
 482                         data_resource.start <= res->end &&
 483                         data_resource.end > res->end) {
 484                         sub_res = alloc_bootmem_low(sizeof(struct resource));
 485                         memcpy(sub_res, &data_resource,
 486                                 sizeof(struct resource));
 487                         sub_res->end = res->end;
 488                         data_resource.start = res->end + 1;
 489                         request_resource(res, sub_res);
 490                 }
 491
 492                 if (data_resource.start >= res->start &&
 493                         data_resource.start <= res->end &&
 494                         data_resource.end <= res->end)
 495                         request_resource(res, &data_resource);
 496         }
 497 }
 498
 499 unsigned long real_memory_size;
 500 EXPORT_SYMBOL_GPL(real_memory_size);
 501
 502 static void __init setup_memory_end(void)
 503 {
 504         unsigned long memory_size;
 505         unsigned long max_mem;
 506         int i;
 507
 508 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
 509         if (ipl_info.type == IPL_TYPE_FCP_DUMP)
 510                 memory_end = ZFCPDUMP_HSA_SIZE;
 511 #endif
 512         memory_size = 0;
 513         memory_end &= PAGE_MASK;
 514
 515         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
 516         memory_end = min(max_mem, memory_end);
 517
 518         /*
 519          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 520          * extra checks that HOLES_IN_ZONE would require.
 521          */
 522         for (i = 0; i < MEMORY_CHUNKS; i++) {
 523                 unsigned long start, end;
 524                 struct mem_chunk *chunk;
 525                 unsigned long align;
 526
 527                 chunk = &memory_chunk[i];
 528                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 529                 start = (chunk->addr + align - 1) & ~(align - 1);
 530                 end = (chunk->addr + chunk->size) & ~(align - 1);
 531                 if (start >= end)
 532                         memset(chunk, 0, sizeof(*chunk));
 533                 else {
 534                         chunk->addr = start;
 535                         chunk->size = end - start;
 536                 }
 537         }
 538
 539         for (i = 0; i < MEMORY_CHUNKS; i++) {
 540                 struct mem_chunk *chunk = &memory_chunk[i];
 541
 542                 real_memory_size = max(real_memory_size,
 543                                        chunk->addr + chunk->size);
 544                 if (chunk->addr >= max_mem) {
 545                         memset(chunk, 0, sizeof(*chunk));
 546                         continue;
 547                 }
 548                 if (chunk->addr + chunk->size > max_mem)
 549                         chunk->size = max_mem - chunk->addr;
 550                 memory_size = max(memory_size, chunk->addr + chunk->size);
 551         }
 552         if (!memory_end)
 553                 memory_end = memory_size;
 554 }
 555
 556 static void __init
 557 setup_memory(void)
 558 {
 559         unsigned long bootmap_size;
 560         unsigned long start_pfn, end_pfn;
 561         int i;
 562
 563         /*
 564          * partially used pages are not usable - thus
 565          * we are rounding upwards:
 566          */
 567         start_pfn = PFN_UP(__pa(&_end));
 568         end_pfn = max_pfn = PFN_DOWN(memory_end);
 569
 570 #ifdef CONFIG_BLK_DEV_INITRD
 571         /*
 572          * Move the initrd in case the bitmap of the bootmem allocater
 573          * would overwrite it.
 574          */
 575
 576         if (INITRD_START && INITRD_SIZE) {
 577                 unsigned long bmap_size;
 578                 unsigned long start;
 579
 580                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 581                 bmap_size = PFN_PHYS(bmap_size);
 582
 583                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 584                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 585
 586                         if (start + INITRD_SIZE > memory_end) {
 587                                 pr_err("initrd extends beyond end of "
 588                                        "memory (0x%08lx > 0x%08lx) "
 589                                        "disabling initrd\n",
 590                                        start + INITRD_SIZE, memory_end);
 591                                 INITRD_START = INITRD_SIZE = 0;
 592                         } else {
 593                                 pr_info("Moving initrd (0x%08lx -> "
 594                                         "0x%08lx, size: %ld)\n",
 595                                         INITRD_START, start, INITRD_SIZE);
 596                                 memmove((void *) start, (void *) INITRD_START,
 597                                         INITRD_SIZE);
 598                                 INITRD_START = start;
 599                         }
 600                 }
 601         }
 602 #endif
 603
 604         /*
 605          * Initialize the boot-time allocator
 606          */
 607         bootmap_size = init_bootmem(start_pfn, end_pfn);
 608
 609         /*
 610          * Register RAM areas with the bootmem allocator.
 611          */
 612
 613         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
 614                 unsigned long start_chunk, end_chunk, pfn;
 615
 616                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
 617                         continue;
 618                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 619                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 620                 end_chunk = min(end_chunk, end_pfn);
 621                 if (start_chunk >= end_chunk)
 622                         continue;
 623                 add_active_range(0, start_chunk, end_chunk);
 624                 pfn = max(start_chunk, start_pfn);
 625                 for (; pfn < end_chunk; pfn++)
 626                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
 627         }
 628
 629         psw_set_key(PAGE_DEFAULT_KEY);
 630
 631         free_bootmem_with_active_regions(0, max_pfn);
 632
 633         /*
 634          * Reserve memory used for lowcore/command line/kernel image.
 635          */
 636         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 637         reserve_bootmem((unsigned long)_stext,
 638                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 639                         BOOTMEM_DEFAULT);
 640         /*
 641          * Reserve the bootmem bitmap itself as well. We do this in two
 642          * steps (first step was init_bootmem()) because this catches
 643          * the (very unlikely) case of us accidentally initializing the
 644          * bootmem allocator with an invalid RAM area.
 645          */
 646         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 647                         BOOTMEM_DEFAULT);
 648
 649 #ifdef CONFIG_BLK_DEV_INITRD
 650         if (INITRD_START && INITRD_SIZE) {
 651                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 652                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 653                                         BOOTMEM_DEFAULT);
 654                         initrd_start = INITRD_START;
 655                         initrd_end = initrd_start + INITRD_SIZE;
 656                 } else {
 657                         pr_err("initrd extends beyond end of "
 658                                "memory (0x%08lx > 0x%08lx) "
 659                                "disabling initrd\n",
 660                                initrd_start + INITRD_SIZE, memory_end);
 661                         initrd_start = initrd_end = 0;
 662                 }
 663         }
 664 #endif
 665 }
 666
 667 /*
 668  * Setup hardware capabilities.
 669  */
 670 static void __init setup_hwcaps(void)
 671 {
 672         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 673         struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
 674         unsigned long long facility_list_extended;
 675         unsigned int facility_list;
 676         int i;
 677
 678         facility_list = stfl();
 679         /*
 680          * The store facility list bits numbers as found in the principles
 681          * of operation are numbered with bit 1UL<<31 as number 0 to
 682          * bit 1UL<<0 as number 31.
 683          *   Bit 0: instructions named N3, "backported" to esa-mode
 684          *   Bit 2: z/Architecture mode is active
 685          *   Bit 7: the store-facility-list-extended facility is installed
 686          *   Bit 17: the message-security assist is installed
 687          *   Bit 19: the long-displacement facility is installed
 688          *   Bit 21: the extended-immediate facility is installed
 689          * These get translated to:
 690          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 691          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 692          *   HWCAP_S390_LDISP bit 4, and HWCAP_S390_EIMM bit 5.
 693          */
 694         for (i = 0; i < 6; i++)
 695                 if (facility_list & (1UL << (31 - stfl_bits[i])))
 696                         elf_hwcap |= 1UL << i;
 697
 698         /*
 699          * Check for additional facilities with store-facility-list-extended.
 700          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 701          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 702          * as stored by stfl, bits 32-xxx contain additional facilities.
 703          * How many facility words are stored depends on the number of
 704          * doublewords passed to the instruction. The additional facilites
 705          * are:
 706          *   Bit 43: decimal floating point facility is installed
 707          * translated to:
 708          *   HWCAP_S390_DFP bit 6.
 709          */
 710         if ((elf_hwcap & (1UL << 2)) &&
 711             __stfle(&facility_list_extended, 1) > 0) {
 712                 if (facility_list_extended & (1ULL << (64 - 43)))
 713                         elf_hwcap |= 1UL << 6;
 714         }
 715
 716         if (MACHINE_HAS_HPAGE)
 717                 elf_hwcap |= 1UL << 7;
 718
 719         switch (cpuinfo->cpu_id.machine) {
 720         case 0x9672:
 721 #if !defined(CONFIG_64BIT)
 722         default:        /* Use "g5" as default for 31 bit kernels. */
 723 #endif
 724                 strcpy(elf_platform, "g5");
 725                 break;
 726         case 0x2064:
 727         case 0x2066:
 728 #if defined(CONFIG_64BIT)
 729         default:        /* Use "z900" as default for 64 bit kernels. */
 730 #endif
 731                 strcpy(elf_platform, "z900");
 732                 break;
 733         case 0x2084:
 734         case 0x2086:
 735                 strcpy(elf_platform, "z990");
 736                 break;
 737         case 0x2094:
 738         case 0x2096:
 739                 strcpy(elf_platform, "z9-109");
 740                 break;
 741         case 0x2097:
 742         case 0x2098:
 743                 strcpy(elf_platform, "z10");
 744                 break;
 745         }
 746 }
 747
 748 /*
 749  * Setup function called from init/main.c just after the banner
 750  * was printed.
 751  */
 752
 753 void __init
 754 setup_arch(char **cmdline_p)
 755 {
 756         /* set up preferred console */
 757         add_preferred_console("ttyS", 0, NULL);
 758
 759         /*
 760          * print what head.S has found out about the machine
 761          */
 762 #ifndef CONFIG_64BIT
 763         if (MACHINE_IS_VM)
 764                 pr_info("Linux is running as a z/VM "
 765                         "guest operating system in 31-bit mode\n");
 766         else
 767                 pr_info("Linux is running natively in 31-bit mode\n");
 768         if (MACHINE_HAS_IEEE)
 769                 pr_info("The hardware system has IEEE compatible "
 770                         "floating point units\n");
 771         else
 772                 pr_info("The hardware system has no IEEE compatible "
 773                         "floating point units\n");
 774 #else /* CONFIG_64BIT */
 775         if (MACHINE_IS_VM)
 776                 pr_info("Linux is running as a z/VM "
 777                         "guest operating system in 64-bit mode\n");
 778         else if (MACHINE_IS_KVM) {
 779                 pr_info("Linux is running under KVM in 64-bit mode\n");
 780                 add_preferred_console("hvc", 0, NULL);
 781                 s390_virtio_console_init();
 782         } else
 783                 pr_info("Linux is running natively in 64-bit mode\n");
 784 #endif /* CONFIG_64BIT */
 785
 786         /* Have one command line that is parsed and saved in /proc/cmdline */
 787         /* boot_command_line has been already set up in early.c */
 788         *cmdline_p = boot_command_line;
 789
 790         ROOT_DEV = Root_RAM0;
 791
 792         init_mm.start_code = PAGE_OFFSET;
 793         init_mm.end_code = (unsigned long) &_etext;
 794         init_mm.end_data = (unsigned long) &_edata;
 795         init_mm.brk = (unsigned long) &_end;
 796
 797         if (MACHINE_HAS_MVCOS)
 798                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
 799         else
 800                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 801
 802         parse_early_param();
 803
 804         setup_ipl();
 805         setup_memory_end();
 806         setup_addressing_mode();
 807         setup_memory();
 808         setup_resources();
 809         setup_lowcore();
 810
 811         cpu_init();
 812         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
 813         s390_init_cpu_topology();
 814
 815         /*
 816          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
 817          */
 818         setup_hwcaps();
 819
 820         /*
 821          * Create kernel page tables and switch to virtual addressing.
 822          */
 823         paging_init();
 824
 825         /* Setup default console */
 826         conmode_default();
 827
 828         /* Setup zfcpdump support */
 829         setup_zfcpdump(console_devno);
 830 }