arch/s390/kernel/setup.c

   1 /*
   2  *  S390 version
   3  *    Copyright IBM Corp. 1999, 2012
   4  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   6  *
   7  *  Derived from "arch/i386/kernel/setup.c"
   8  *    Copyright (C) 1995, Linus Torvalds
   9  */
  10
  11 /*
  12  * This file handles the architecture-dependent parts of initialization
  13  */
  14
  15 #define KMSG_COMPONENT "setup"
  16 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  17
  18 #include <linux/errno.h>
  19 #include <linux/export.h>
  20 #include <linux/sched.h>
  21 #include <linux/kernel.h>
  22 #include <linux/memblock.h>
  23 #include <linux/mm.h>
  24 #include <linux/stddef.h>
  25 #include <linux/unistd.h>
  26 #include <linux/ptrace.h>
  27 #include <linux/user.h>
  28 #include <linux/tty.h>
  29 #include <linux/ioport.h>
  30 #include <linux/delay.h>
  31 #include <linux/init.h>
  32 #include <linux/initrd.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/root_dev.h>
  35 #include <linux/console.h>
  36 #include <linux/kernel_stat.h>
  37 #include <linux/device.h>
  38 #include <linux/notifier.h>
  39 #include <linux/pfn.h>
  40 #include <linux/ctype.h>
  41 #include <linux/reboot.h>
  42 #include <linux/topology.h>
  43 #include <linux/ftrace.h>
  44 #include <linux/kexec.h>
  45 #include <linux/crash_dump.h>
  46 #include <linux/memory.h>
  47 #include <linux/compat.h>
  48
  49 #include <asm/ipl.h>
  50 #include <asm/uaccess.h>
  51 #include <asm/facility.h>
  52 #include <asm/smp.h>
  53 #include <asm/mmu_context.h>
  54 #include <asm/cpcmd.h>
  55 #include <asm/lowcore.h>
  56 #include <asm/irq.h>
  57 #include <asm/page.h>
  58 #include <asm/ptrace.h>
  59 #include <asm/sections.h>
  60 #include <asm/ebcdic.h>
  61 #include <asm/kvm_virtio.h>
  62 #include <asm/diag.h>
  63 #include <asm/os_info.h>
  64 #include <asm/sclp.h>
  65 #include "entry.h"
  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 unsigned long VMALLOC_START;
  94 EXPORT_SYMBOL(VMALLOC_START);
  95
  96 unsigned long VMALLOC_END;
  97 EXPORT_SYMBOL(VMALLOC_END);
  98
  99 struct page *vmemmap;
 100 EXPORT_SYMBOL(vmemmap);
 101
 102 #ifdef CONFIG_64BIT
 103 unsigned long MODULES_VADDR;
 104 unsigned long MODULES_END;
 105 #endif
 106
 107 /* An array with a pointer to the lowcore of every CPU. */
 108 struct _lowcore *lowcore_ptr[NR_CPUS];
 109 EXPORT_SYMBOL(lowcore_ptr);
 110
 111 /*
 112  * This is set up by the setup-routine at boot-time
 113  * for S390 need to find out, what we have to setup
 114  * using address 0x10400 ...
 115  */
 116
 117 #include <asm/setup.h>
 118
 119 /*
 120  * condev= and conmode= setup parameter.
 121  */
 122
 123 static int __init condev_setup(char *str)
 124 {
 125         int vdev;
 126
 127         vdev = simple_strtoul(str, &str, 0);
 128         if (vdev >= 0 && vdev < 65536) {
 129                 console_devno = vdev;
 130                 console_irq = -1;
 131         }
 132         return 1;
 133 }
 134
 135 __setup("condev=", condev_setup);
 136
 137 static void __init set_preferred_console(void)
 138 {
 139         if (MACHINE_IS_KVM) {
 140                 if (sclp_has_vt220())
 141                         add_preferred_console("ttyS", 1, NULL);
 142                 else if (sclp_has_linemode())
 143                         add_preferred_console("ttyS", 0, NULL);
 144                 else
 145                         add_preferred_console("hvc", 0, NULL);
 146         } else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 147                 add_preferred_console("ttyS", 0, NULL);
 148         else if (CONSOLE_IS_3270)
 149                 add_preferred_console("tty3270", 0, NULL);
 150 }
 151
 152 static int __init conmode_setup(char *str)
 153 {
 154 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 155         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
 156                 SET_CONSOLE_SCLP;
 157 #endif
 158 #if defined(CONFIG_TN3215_CONSOLE)
 159         if (strncmp(str, "3215", 5) == 0)
 160                 SET_CONSOLE_3215;
 161 #endif
 162 #if defined(CONFIG_TN3270_CONSOLE)
 163         if (strncmp(str, "3270", 5) == 0)
 164                 SET_CONSOLE_3270;
 165 #endif
 166         set_preferred_console();
 167         return 1;
 168 }
 169
 170 __setup("conmode=", conmode_setup);
 171
 172 static void __init conmode_default(void)
 173 {
 174         char query_buffer[1024];
 175         char *ptr;
 176
 177         if (MACHINE_IS_VM) {
 178                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 179                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 180                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 181                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 182                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 183                 ptr = strstr(query_buffer, "CONMODE");
 184                 /*
 185                  * Set the conmode to 3215 so that the device recognition
 186                  * will set the cu_type of the console to 3215. If the
 187                  * conmode is 3270 and we don't set it back then both
 188                  * 3215 and the 3270 driver will try to access the console
 189                  * device (3215 as console and 3270 as normal tty).
 190                  */
 191                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 192                 if (ptr == NULL) {
 193 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 194                         SET_CONSOLE_SCLP;
 195 #endif
 196                         return;
 197                 }
 198                 if (strncmp(ptr + 8, "3270", 4) == 0) {
 199 #if defined(CONFIG_TN3270_CONSOLE)
 200                         SET_CONSOLE_3270;
 201 #elif defined(CONFIG_TN3215_CONSOLE)
 202                         SET_CONSOLE_3215;
 203 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 204                         SET_CONSOLE_SCLP;
 205 #endif
 206                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
 207 #if defined(CONFIG_TN3215_CONSOLE)
 208                         SET_CONSOLE_3215;
 209 #elif defined(CONFIG_TN3270_CONSOLE)
 210                         SET_CONSOLE_3270;
 211 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 212                         SET_CONSOLE_SCLP;
 213 #endif
 214                 }
 215         } else {
 216 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 217                 SET_CONSOLE_SCLP;
 218 #endif
 219         }
 220 }
 221
 222 #ifdef CONFIG_ZFCPDUMP
 223 static void __init setup_zfcpdump(void)
 224 {
 225         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 226                 return;
 227         if (OLDMEM_BASE)
 228                 return;
 229         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 230         console_loglevel = 2;
 231 }
 232 #else
 233 static inline void setup_zfcpdump(void) {}
 234 #endif /* CONFIG_ZFCPDUMP */
 235
 236  /*
 237  * Reboot, halt and power_off stubs. They just call _machine_restart,
 238  * _machine_halt or _machine_power_off.
 239  */
 240
 241 void machine_restart(char *command)
 242 {
 243         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 244                 /*
 245                  * Only unblank the console if we are called in enabled
 246                  * context or a bust_spinlocks cleared the way for us.
 247                  */
 248                 console_unblank();
 249         _machine_restart(command);
 250 }
 251
 252 void machine_halt(void)
 253 {
 254         if (!in_interrupt() || oops_in_progress)
 255                 /*
 256                  * Only unblank the console if we are called in enabled
 257                  * context or a bust_spinlocks cleared the way for us.
 258                  */
 259                 console_unblank();
 260         _machine_halt();
 261 }
 262
 263 void machine_power_off(void)
 264 {
 265         if (!in_interrupt() || oops_in_progress)
 266                 /*
 267                  * Only unblank the console if we are called in enabled
 268                  * context or a bust_spinlocks cleared the way for us.
 269                  */
 270                 console_unblank();
 271         _machine_power_off();
 272 }
 273
 274 /*
 275  * Dummy power off function.
 276  */
 277 void (*pm_power_off)(void) = machine_power_off;
 278 EXPORT_SYMBOL_GPL(pm_power_off);
 279
 280 static int __init early_parse_mem(char *p)
 281 {
 282         memory_end = memparse(p, &p);
 283         memory_end_set = 1;
 284         return 0;
 285 }
 286 early_param("mem", early_parse_mem);
 287
 288 static int __init parse_vmalloc(char *arg)
 289 {
 290         if (!arg)
 291                 return -EINVAL;
 292         VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
 293         return 0;
 294 }
 295 early_param("vmalloc", parse_vmalloc);
 296
 297 static int __init early_parse_user_mode(char *p)
 298 {
 299         if (!p || strcmp(p, "primary") == 0)
 300                 return 0;
 301         return 1;
 302 }
 303 early_param("user_mode", early_parse_user_mode);
 304
 305 void *restart_stack __attribute__((__section__(".data")));
 306
 307 static void __init setup_lowcore(void)
 308 {
 309         struct _lowcore *lc;
 310
 311         /*
 312          * Setup lowcore for boot cpu
 313          */
 314         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
 315         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
 316         lc->restart_psw.mask = PSW_KERNEL_BITS;
 317         lc->restart_psw.addr =
 318                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
 319         lc->external_new_psw.mask = PSW_KERNEL_BITS |
 320                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 321         lc->external_new_psw.addr =
 322                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
 323         lc->svc_new_psw.mask = PSW_KERNEL_BITS |
 324                 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 325         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
 326         lc->program_new_psw.mask = PSW_KERNEL_BITS |
 327                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 328         lc->program_new_psw.addr =
 329                 PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
 330         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 331         lc->mcck_new_psw.addr =
 332                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
 333         lc->io_new_psw.mask = PSW_KERNEL_BITS |
 334                 PSW_MASK_DAT | PSW_MASK_MCHECK;
 335         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
 336         lc->clock_comparator = -1ULL;
 337         lc->kernel_stack = ((unsigned long) &init_thread_union)
 338                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 339         lc->async_stack = (unsigned long)
 340                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0)
 341                 + ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 342         lc->panic_stack = (unsigned long)
 343                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0)
 344                 + PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 345         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
 346         lc->thread_info = (unsigned long) &init_thread_union;
 347         lc->machine_flags = S390_lowcore.machine_flags;
 348         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 349         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 350                MAX_FACILITY_BIT/8);
 351 #ifndef CONFIG_64BIT
 352         if (MACHINE_HAS_IEEE) {
 353                 lc->extended_save_area_addr = (__u32)
 354                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
 355                 /* enable extended save area */
 356                 __ctl_set_bit(14, 29);
 357         }
 358 #else
 359         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
 360 #endif
 361         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 362         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 363         lc->exit_timer = S390_lowcore.exit_timer;
 364         lc->user_timer = S390_lowcore.user_timer;
 365         lc->system_timer = S390_lowcore.system_timer;
 366         lc->steal_timer = S390_lowcore.steal_timer;
 367         lc->last_update_timer = S390_lowcore.last_update_timer;
 368         lc->last_update_clock = S390_lowcore.last_update_clock;
 369         lc->ftrace_func = S390_lowcore.ftrace_func;
 370
 371         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
 372         restart_stack += ASYNC_SIZE;
 373
 374         /*
 375          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 376          * restart data to the absolute zero lowcore. This is necessary if
 377          * PSW restart is done on an offline CPU that has lowcore zero.
 378          */
 379         lc->restart_stack = (unsigned long) restart_stack;
 380         lc->restart_fn = (unsigned long) do_restart;
 381         lc->restart_data = 0;
 382         lc->restart_source = -1UL;
 383
 384         /* Setup absolute zero lowcore */
 385         mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
 386         mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
 387         mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
 388         mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
 389         mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 390
 391         set_prefix((u32)(unsigned long) lc);
 392         lowcore_ptr[0] = lc;
 393 }
 394
 395 static struct resource code_resource = {
 396         .name  = "Kernel code",
 397         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 398 };
 399
 400 static struct resource data_resource = {
 401         .name = "Kernel data",
 402         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 403 };
 404
 405 static struct resource bss_resource = {
 406         .name = "Kernel bss",
 407         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
 408 };
 409
 410 static struct resource __initdata *standard_resources[] = {
 411         &code_resource,
 412         &data_resource,
 413         &bss_resource,
 414 };
 415
 416 static void __init setup_resources(void)
 417 {
 418         struct resource *res, *std_res, *sub_res;
 419         int i, j;
 420
 421         code_resource.start = (unsigned long) &_text;
 422         code_resource.end = (unsigned long) &_etext - 1;
 423         data_resource.start = (unsigned long) &_etext;
 424         data_resource.end = (unsigned long) &_edata - 1;
 425         bss_resource.start = (unsigned long) &__bss_start;
 426         bss_resource.end = (unsigned long) &__bss_stop - 1;
 427
 428         for (i = 0; i < MEMORY_CHUNKS; i++) {
 429                 if (!memory_chunk[i].size)
 430                         continue;
 431                 res = alloc_bootmem_low(sizeof(*res));
 432                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 433                 switch (memory_chunk[i].type) {
 434                 case CHUNK_READ_WRITE:
 435                         res->name = "System RAM";
 436                         break;
 437                 case CHUNK_READ_ONLY:
 438                         res->name = "System ROM";
 439                         res->flags |= IORESOURCE_READONLY;
 440                         break;
 441                 default:
 442                         res->name = "reserved";
 443                 }
 444                 res->start = memory_chunk[i].addr;
 445                 res->end = res->start + memory_chunk[i].size - 1;
 446                 request_resource(&iomem_resource, res);
 447
 448                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 449                         std_res = standard_resources[j];
 450                         if (std_res->start < res->start ||
 451                             std_res->start > res->end)
 452                                 continue;
 453                         if (std_res->end > res->end) {
 454                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
 455                                 *sub_res = *std_res;
 456                                 sub_res->end = res->end;
 457                                 std_res->start = res->end + 1;
 458                                 request_resource(res, sub_res);
 459                         } else {
 460                                 request_resource(res, std_res);
 461                         }
 462                 }
 463         }
 464 }
 465
 466 static void __init setup_memory_end(void)
 467 {
 468         unsigned long vmax, vmalloc_size, tmp;
 469         unsigned long real_memory_size = 0;
 470         int i;
 471
 472
 473 #ifdef CONFIG_ZFCPDUMP
 474         if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
 475             !OLDMEM_BASE && sclp_get_hsa_size()) {
 476                 memory_end = sclp_get_hsa_size();
 477                 memory_end_set = 1;
 478         }
 479 #endif
 480         memory_end &= PAGE_MASK;
 481
 482         /*
 483          * Make sure all chunks are MAX_ORDER aligned so we don't need the
 484          * extra checks that HOLES_IN_ZONE would require.
 485          */
 486         for (i = 0; i < MEMORY_CHUNKS; i++) {
 487                 unsigned long start, end;
 488                 struct mem_chunk *chunk;
 489                 unsigned long align;
 490
 491                 chunk = &memory_chunk[i];
 492                 if (!chunk->size)
 493                         continue;
 494                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
 495                 start = (chunk->addr + align - 1) & ~(align - 1);
 496                 end = (chunk->addr + chunk->size) & ~(align - 1);
 497                 if (start >= end)
 498                         memset(chunk, 0, sizeof(*chunk));
 499                 else {
 500                         chunk->addr = start;
 501                         chunk->size = end - start;
 502                 }
 503                 real_memory_size = max(real_memory_size,
 504                                        chunk->addr + chunk->size);
 505         }
 506
 507         /* Choose kernel address space layout: 2, 3, or 4 levels. */
 508 #ifdef CONFIG_64BIT
 509         vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
 510         tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
 511         tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
 512         if (tmp <= (1UL << 42))
 513                 vmax = 1UL << 42;       /* 3-level kernel page table */
 514         else
 515                 vmax = 1UL << 53;       /* 4-level kernel page table */
 516         /* module area is at the end of the kernel address space. */
 517         MODULES_END = vmax;
 518         MODULES_VADDR = MODULES_END - MODULES_LEN;
 519         VMALLOC_END = MODULES_VADDR;
 520 #else
 521         vmalloc_size = VMALLOC_END ?: 96UL << 20;
 522         vmax = 1UL << 31;               /* 2-level kernel page table */
 523         /* vmalloc area is at the end of the kernel address space. */
 524         VMALLOC_END = vmax;
 525 #endif
 526         VMALLOC_START = vmax - vmalloc_size;
 527
 528         /* Split remaining virtual space between 1:1 mapping & vmemmap array */
 529         tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
 530         /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
 531         tmp = SECTION_ALIGN_UP(tmp);
 532         tmp = VMALLOC_START - tmp * sizeof(struct page);
 533         tmp &= ~((vmax >> 11) - 1);     /* align to page table level */
 534         tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
 535         vmemmap = (struct page *) tmp;
 536
 537         /* Take care that memory_end is set and <= vmemmap */
 538         memory_end = min(memory_end ?: real_memory_size, tmp);
 539
 540         /* Fixup memory chunk array to fit into 0..memory_end */
 541         for (i = 0; i < MEMORY_CHUNKS; i++) {
 542                 struct mem_chunk *chunk = &memory_chunk[i];
 543
 544                 if (!chunk->size)
 545                         continue;
 546                 if (chunk->addr >= memory_end) {
 547                         memset(chunk, 0, sizeof(*chunk));
 548                         continue;
 549                 }
 550                 if (chunk->addr + chunk->size > memory_end)
 551                         chunk->size = memory_end - chunk->addr;
 552         }
 553 }
 554
 555 static void __init setup_vmcoreinfo(void)
 556 {
 557         mem_assign_absolute(S390_lowcore.vmcore_info, paddr_vmcoreinfo_note());
 558 }
 559
 560 #ifdef CONFIG_CRASH_DUMP
 561
 562 /*
 563  * Find suitable location for crashkernel memory
 564  */
 565 static unsigned long __init find_crash_base(unsigned long crash_size,
 566                                             char **msg)
 567 {
 568         unsigned long crash_base;
 569         struct mem_chunk *chunk;
 570         int i;
 571
 572         if (memory_chunk[0].size < crash_size) {
 573                 *msg = "first memory chunk must be at least crashkernel size";
 574                 return 0;
 575         }
 576         if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
 577                 return OLDMEM_BASE;
 578
 579         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
 580                 chunk = &memory_chunk[i];
 581                 if (chunk->size == 0)
 582                         continue;
 583                 if (chunk->type != CHUNK_READ_WRITE)
 584                         continue;
 585                 if (chunk->size < crash_size)
 586                         continue;
 587                 crash_base = (chunk->addr + chunk->size) - crash_size;
 588                 if (crash_base < crash_size)
 589                         continue;
 590                 if (crash_base < sclp_get_hsa_size())
 591                         continue;
 592                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
 593                         continue;
 594                 return crash_base;
 595         }
 596         *msg = "no suitable area found";
 597         return 0;
 598 }
 599
 600 /*
 601  * Check if crash_base and crash_size is valid
 602  */
 603 static int __init verify_crash_base(unsigned long crash_base,
 604                                     unsigned long crash_size,
 605                                     char **msg)
 606 {
 607         struct mem_chunk *chunk;
 608         int i;
 609
 610         /*
 611          * Because we do the swap to zero, we must have at least 'crash_size'
 612          * bytes free space before crash_base
 613          */
 614         if (crash_size > crash_base) {
 615                 *msg = "crashkernel offset must be greater than size";
 616                 return -EINVAL;
 617         }
 618
 619         /* First memory chunk must be at least crash_size */
 620         if (memory_chunk[0].size < crash_size) {
 621                 *msg = "first memory chunk must be at least crashkernel size";
 622                 return -EINVAL;
 623         }
 624         /* Check if we fit into the respective memory chunk */
 625         for (i = 0; i < MEMORY_CHUNKS; i++) {
 626                 chunk = &memory_chunk[i];
 627                 if (chunk->size == 0)
 628                         continue;
 629                 if (crash_base < chunk->addr)
 630                         continue;
 631                 if (crash_base >= chunk->addr + chunk->size)
 632                         continue;
 633                 /* we have found the memory chunk */
 634                 if (crash_base + crash_size > chunk->addr + chunk->size) {
 635                         *msg = "selected memory chunk is too small for "
 636                                 "crashkernel memory";
 637                         return -EINVAL;
 638                 }
 639                 return 0;
 640         }
 641         *msg = "invalid memory range specified";
 642         return -EINVAL;
 643 }
 644
 645 /*
 646  * When kdump is enabled, we have to ensure that no memory from
 647  * the area [0 - crashkernel memory size] and
 648  * [crashk_res.start - crashk_res.end] is set offline.
 649  */
 650 static int kdump_mem_notifier(struct notifier_block *nb,
 651                               unsigned long action, void *data)
 652 {
 653         struct memory_notify *arg = data;
 654
 655         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 656                 return NOTIFY_BAD;
 657         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 658                 return NOTIFY_OK;
 659         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 660                 return NOTIFY_OK;
 661         return NOTIFY_BAD;
 662 }
 663
 664 static struct notifier_block kdump_mem_nb = {
 665         .notifier_call = kdump_mem_notifier,
 666 };
 667
 668 #endif
 669
 670 /*
 671  * Make sure that oldmem, where the dump is stored, is protected
 672  */
 673 static void reserve_oldmem(void)
 674 {
 675 #ifdef CONFIG_CRASH_DUMP
 676         unsigned long real_size = 0;
 677         int i;
 678
 679         if (!OLDMEM_BASE)
 680                 return;
 681         for (i = 0; i < MEMORY_CHUNKS; i++) {
 682                 struct mem_chunk *chunk = &memory_chunk[i];
 683
 684                 real_size = max(real_size, chunk->addr + chunk->size);
 685         }
 686         create_mem_hole(memory_chunk, OLDMEM_BASE, OLDMEM_SIZE);
 687         create_mem_hole(memory_chunk, OLDMEM_SIZE, real_size - OLDMEM_SIZE);
 688 #endif
 689 }
 690
 691 /*
 692  * Reserve memory for kdump kernel to be loaded with kexec
 693  */
 694 static void __init reserve_crashkernel(void)
 695 {
 696 #ifdef CONFIG_CRASH_DUMP
 697         unsigned long long crash_base, crash_size;
 698         char *msg = NULL;
 699         int rc;
 700
 701         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 702                                &crash_base);
 703         if (rc || crash_size == 0)
 704                 return;
 705         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 706         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 707         if (register_memory_notifier(&kdump_mem_nb))
 708                 return;
 709         if (!crash_base)
 710                 crash_base = find_crash_base(crash_size, &msg);
 711         if (!crash_base) {
 712                 pr_info("crashkernel reservation failed: %s\n", msg);
 713                 unregister_memory_notifier(&kdump_mem_nb);
 714                 return;
 715         }
 716         if (verify_crash_base(crash_base, crash_size, &msg)) {
 717                 pr_info("crashkernel reservation failed: %s\n", msg);
 718                 unregister_memory_notifier(&kdump_mem_nb);
 719                 return;
 720         }
 721         if (!OLDMEM_BASE && MACHINE_IS_VM)
 722                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 723         crashk_res.start = crash_base;
 724         crashk_res.end = crash_base + crash_size - 1;
 725         insert_resource(&iomem_resource, &crashk_res);
 726         create_mem_hole(memory_chunk, crash_base, crash_size);
 727         pr_info("Reserving %lluMB of memory at %lluMB "
 728                 "for crashkernel (System RAM: %luMB)\n",
 729                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
 730         os_info_crashkernel_add(crash_base, crash_size);
 731 #endif
 732 }
 733
 734 static void __init setup_memory(void)
 735 {
 736         unsigned long bootmap_size;
 737         unsigned long start_pfn, end_pfn;
 738         int i;
 739
 740         /*
 741          * partially used pages are not usable - thus
 742          * we are rounding upwards:
 743          */
 744         start_pfn = PFN_UP(__pa(&_end));
 745         end_pfn = max_pfn = PFN_DOWN(memory_end);
 746
 747 #ifdef CONFIG_BLK_DEV_INITRD
 748         /*
 749          * Move the initrd in case the bitmap of the bootmem allocater
 750          * would overwrite it.
 751          */
 752
 753         if (INITRD_START && INITRD_SIZE) {
 754                 unsigned long bmap_size;
 755                 unsigned long start;
 756
 757                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
 758                 bmap_size = PFN_PHYS(bmap_size);
 759
 760                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
 761                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
 762
 763 #ifdef CONFIG_CRASH_DUMP
 764                         if (OLDMEM_BASE) {
 765                                 /* Move initrd behind kdump oldmem */
 766                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
 767                                     start < OLDMEM_BASE + OLDMEM_SIZE)
 768                                         start = OLDMEM_BASE + OLDMEM_SIZE;
 769                         }
 770 #endif
 771                         if (start + INITRD_SIZE > memory_end) {
 772                                 pr_err("initrd extends beyond end of "
 773                                        "memory (0x%08lx > 0x%08lx) "
 774                                        "disabling initrd\n",
 775                                        start + INITRD_SIZE, memory_end);
 776                                 INITRD_START = INITRD_SIZE = 0;
 777                         } else {
 778                                 pr_info("Moving initrd (0x%08lx -> "
 779                                         "0x%08lx, size: %ld)\n",
 780                                         INITRD_START, start, INITRD_SIZE);
 781                                 memmove((void *) start, (void *) INITRD_START,
 782                                         INITRD_SIZE);
 783                                 INITRD_START = start;
 784                         }
 785                 }
 786         }
 787 #endif
 788
 789         /*
 790          * Initialize the boot-time allocator
 791          */
 792         bootmap_size = init_bootmem(start_pfn, end_pfn);
 793
 794         /*
 795          * Register RAM areas with the bootmem allocator.
 796          */
 797
 798         for (i = 0; i < MEMORY_CHUNKS; i++) {
 799                 unsigned long start_chunk, end_chunk, pfn;
 800
 801                 if (!memory_chunk[i].size)
 802                         continue;
 803                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
 804                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
 805                 end_chunk = min(end_chunk, end_pfn);
 806                 if (start_chunk >= end_chunk)
 807                         continue;
 808                 memblock_add_node(PFN_PHYS(start_chunk),
 809                                   PFN_PHYS(end_chunk - start_chunk), 0);
 810                 pfn = max(start_chunk, start_pfn);
 811                 storage_key_init_range(PFN_PHYS(pfn), PFN_PHYS(end_chunk));
 812         }
 813
 814         psw_set_key(PAGE_DEFAULT_KEY);
 815
 816         free_bootmem_with_active_regions(0, max_pfn);
 817
 818         /*
 819          * Reserve memory used for lowcore/command line/kernel image.
 820          */
 821         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
 822         reserve_bootmem((unsigned long)_stext,
 823                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
 824                         BOOTMEM_DEFAULT);
 825         /*
 826          * Reserve the bootmem bitmap itself as well. We do this in two
 827          * steps (first step was init_bootmem()) because this catches
 828          * the (very unlikely) case of us accidentally initializing the
 829          * bootmem allocator with an invalid RAM area.
 830          */
 831         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
 832                         BOOTMEM_DEFAULT);
 833
 834 #ifdef CONFIG_CRASH_DUMP
 835         if (crashk_res.start)
 836                 reserve_bootmem(crashk_res.start,
 837                                 crashk_res.end - crashk_res.start + 1,
 838                                 BOOTMEM_DEFAULT);
 839         if (is_kdump_kernel())
 840                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
 841                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
 842 #endif
 843 #ifdef CONFIG_BLK_DEV_INITRD
 844         if (INITRD_START && INITRD_SIZE) {
 845                 if (INITRD_START + INITRD_SIZE <= memory_end) {
 846                         reserve_bootmem(INITRD_START, INITRD_SIZE,
 847                                         BOOTMEM_DEFAULT);
 848                         initrd_start = INITRD_START;
 849                         initrd_end = initrd_start + INITRD_SIZE;
 850                 } else {
 851                         pr_err("initrd extends beyond end of "
 852                                "memory (0x%08lx > 0x%08lx) "
 853                                "disabling initrd\n",
 854                                initrd_start + INITRD_SIZE, memory_end);
 855                         initrd_start = initrd_end = 0;
 856                 }
 857         }
 858 #endif
 859 }
 860
 861 /*
 862  * Setup hardware capabilities.
 863  */
 864 static void __init setup_hwcaps(void)
 865 {
 866         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 867         struct cpuid cpu_id;
 868         int i;
 869
 870         /*
 871          * The store facility list bits numbers as found in the principles
 872          * of operation are numbered with bit 1UL<<31 as number 0 to
 873          * bit 1UL<<0 as number 31.
 874          *   Bit 0: instructions named N3, "backported" to esa-mode
 875          *   Bit 2: z/Architecture mode is active
 876          *   Bit 7: the store-facility-list-extended facility is installed
 877          *   Bit 17: the message-security assist is installed
 878          *   Bit 19: the long-displacement facility is installed
 879          *   Bit 21: the extended-immediate facility is installed
 880          *   Bit 22: extended-translation facility 3 is installed
 881          *   Bit 30: extended-translation facility 3 enhancement facility
 882          * These get translated to:
 883          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 884          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 885          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 886          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 887          */
 888         for (i = 0; i < 6; i++)
 889                 if (test_facility(stfl_bits[i]))
 890                         elf_hwcap |= 1UL << i;
 891
 892         if (test_facility(22) && test_facility(30))
 893                 elf_hwcap |= HWCAP_S390_ETF3EH;
 894
 895         /*
 896          * Check for additional facilities with store-facility-list-extended.
 897          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 898          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 899          * as stored by stfl, bits 32-xxx contain additional facilities.
 900          * How many facility words are stored depends on the number of
 901          * doublewords passed to the instruction. The additional facilities
 902          * are:
 903          *   Bit 42: decimal floating point facility is installed
 904          *   Bit 44: perform floating point operation facility is installed
 905          * translated to:
 906          *   HWCAP_S390_DFP bit 6 (42 && 44).
 907          */
 908         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 909                 elf_hwcap |= HWCAP_S390_DFP;
 910
 911         /*
 912          * Huge page support HWCAP_S390_HPAGE is bit 7.
 913          */
 914         if (MACHINE_HAS_HPAGE)
 915                 elf_hwcap |= HWCAP_S390_HPAGE;
 916
 917 #if defined(CONFIG_64BIT)
 918         /*
 919          * 64-bit register support for 31-bit processes
 920          * HWCAP_S390_HIGH_GPRS is bit 9.
 921          */
 922         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 923
 924         /*
 925          * Transactional execution support HWCAP_S390_TE is bit 10.
 926          */
 927         if (test_facility(50) && test_facility(73))
 928                 elf_hwcap |= HWCAP_S390_TE;
 929 #endif
 930
 931         get_cpu_id(&cpu_id);
 932         switch (cpu_id.machine) {
 933         case 0x9672:
 934 #if !defined(CONFIG_64BIT)
 935         default:        /* Use "g5" as default for 31 bit kernels. */
 936 #endif
 937                 strcpy(elf_platform, "g5");
 938                 break;
 939         case 0x2064:
 940         case 0x2066:
 941 #if defined(CONFIG_64BIT)
 942         default:        /* Use "z900" as default for 64 bit kernels. */
 943 #endif
 944                 strcpy(elf_platform, "z900");
 945                 break;
 946         case 0x2084:
 947         case 0x2086:
 948                 strcpy(elf_platform, "z990");
 949                 break;
 950         case 0x2094:
 951         case 0x2096:
 952                 strcpy(elf_platform, "z9-109");
 953                 break;
 954         case 0x2097:
 955         case 0x2098:
 956                 strcpy(elf_platform, "z10");
 957                 break;
 958         case 0x2817:
 959         case 0x2818:
 960                 strcpy(elf_platform, "z196");
 961                 break;
 962         case 0x2827:
 963         case 0x2828:
 964                 strcpy(elf_platform, "zEC12");
 965                 break;
 966         }
 967 }
 968
 969 /*
 970  * Setup function called from init/main.c just after the banner
 971  * was printed.
 972  */
 973
 974 void __init setup_arch(char **cmdline_p)
 975 {
 976         /*
 977          * print what head.S has found out about the machine
 978          */
 979 #ifndef CONFIG_64BIT
 980         if (MACHINE_IS_VM)
 981                 pr_info("Linux is running as a z/VM "
 982                         "guest operating system in 31-bit mode\n");
 983         else if (MACHINE_IS_LPAR)
 984                 pr_info("Linux is running natively in 31-bit mode\n");
 985         if (MACHINE_HAS_IEEE)
 986                 pr_info("The hardware system has IEEE compatible "
 987                         "floating point units\n");
 988         else
 989                 pr_info("The hardware system has no IEEE compatible "
 990                         "floating point units\n");
 991 #else /* CONFIG_64BIT */
 992         if (MACHINE_IS_VM)
 993                 pr_info("Linux is running as a z/VM "
 994                         "guest operating system in 64-bit mode\n");
 995         else if (MACHINE_IS_KVM)
 996                 pr_info("Linux is running under KVM in 64-bit mode\n");
 997         else if (MACHINE_IS_LPAR)
 998                 pr_info("Linux is running natively in 64-bit mode\n");
 999 #endif /* CONFIG_64BIT */
1000
1001         /* Have one command line that is parsed and saved in /proc/cmdline */
1002         /* boot_command_line has been already set up in early.c */
1003         *cmdline_p = boot_command_line;
1004
1005         ROOT_DEV = Root_RAM0;
1006
1007         init_mm.start_code = PAGE_OFFSET;
1008         init_mm.end_code = (unsigned long) &_etext;
1009         init_mm.end_data = (unsigned long) &_edata;
1010         init_mm.brk = (unsigned long) &_end;
1011
1012         uaccess = MACHINE_HAS_MVCOS ? uaccess_mvcos : uaccess_pt;
1013
1014         parse_early_param();
1015         detect_memory_layout(memory_chunk, memory_end);
1016         os_info_init();
1017         setup_ipl();
1018         reserve_oldmem();
1019         setup_memory_end();
1020         reserve_crashkernel();
1021         setup_memory();
1022         setup_resources();
1023         setup_vmcoreinfo();
1024         setup_lowcore();
1025
1026         smp_fill_possible_mask();
1027         cpu_init();
1028         s390_init_cpu_topology();
1029
1030         /*
1031          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1032          */
1033         setup_hwcaps();
1034
1035         /*
1036          * Create kernel page tables and switch to virtual addressing.
1037          */
1038         paging_init();
1039
1040         /* Setup default console */
1041         conmode_default();
1042         set_preferred_console();
1043
1044         /* Setup zfcpdump support */
1045         setup_zfcpdump();
1046 }