arch/s390/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  S390 version
   4  *    Copyright IBM Corp. 1999, 2012
   5  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7  *
   8  *  Derived from "arch/i386/kernel/setup.c"
   9  *    Copyright (C) 1995, Linus Torvalds
  10  */
  11
  12 /*
  13  * This file handles the architecture-dependent parts of initialization
  14  */
  15
  16 #define KMSG_COMPONENT "setup"
  17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  18
  19 #include <linux/errno.h>
  20 #include <linux/export.h>
  21 #include <linux/sched.h>
  22 #include <linux/sched/task.h>
  23 #include <linux/cpu.h>
  24 #include <linux/kernel.h>
  25 #include <linux/memblock.h>
  26 #include <linux/mm.h>
  27 #include <linux/stddef.h>
  28 #include <linux/unistd.h>
  29 #include <linux/ptrace.h>
  30 #include <linux/random.h>
  31 #include <linux/user.h>
  32 #include <linux/tty.h>
  33 #include <linux/ioport.h>
  34 #include <linux/delay.h>
  35 #include <linux/init.h>
  36 #include <linux/initrd.h>
  37 #include <linux/root_dev.h>
  38 #include <linux/console.h>
  39 #include <linux/kernel_stat.h>
  40 #include <linux/dma-map-ops.h>
  41 #include <linux/device.h>
  42 #include <linux/notifier.h>
  43 #include <linux/pfn.h>
  44 #include <linux/ctype.h>
  45 #include <linux/reboot.h>
  46 #include <linux/topology.h>
  47 #include <linux/kexec.h>
  48 #include <linux/crash_dump.h>
  49 #include <linux/memory.h>
  50 #include <linux/compat.h>
  51 #include <linux/start_kernel.h>
  52 #include <linux/hugetlb.h>
  53
  54 #include <asm/boot_data.h>
  55 #include <asm/ipl.h>
  56 #include <asm/facility.h>
  57 #include <asm/smp.h>
  58 #include <asm/mmu_context.h>
  59 #include <asm/cpcmd.h>
  60 #include <asm/lowcore.h>
  61 #include <asm/nmi.h>
  62 #include <asm/irq.h>
  63 #include <asm/page.h>
  64 #include <asm/ptrace.h>
  65 #include <asm/sections.h>
  66 #include <asm/ebcdic.h>
  67 #include <asm/diag.h>
  68 #include <asm/os_info.h>
  69 #include <asm/sclp.h>
  70 #include <asm/stacktrace.h>
  71 #include <asm/sysinfo.h>
  72 #include <asm/numa.h>
  73 #include <asm/alternative.h>
  74 #include <asm/nospec-branch.h>
  75 #include <asm/mem_detect.h>
  76 #include <asm/uv.h>
  77 #include <asm/asm-offsets.h>
  78 #include "entry.h"
  79
  80 /*
  81  * Machine setup..
  82  */
  83 unsigned int console_mode = 0;
  84 EXPORT_SYMBOL(console_mode);
  85
  86 unsigned int console_devno = -1;
  87 EXPORT_SYMBOL(console_devno);
  88
  89 unsigned int console_irq = -1;
  90 EXPORT_SYMBOL(console_irq);
  91
  92 unsigned long elf_hwcap __read_mostly = 0;
  93 char elf_platform[ELF_PLATFORM_SIZE];
  94
  95 unsigned long int_hwcap = 0;
  96
  97 int __bootdata(noexec_disabled);
  98 unsigned long __bootdata(ident_map_size);
  99 struct mem_detect_info __bootdata(mem_detect);
 100
 101 struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
 102 struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
 103 unsigned long __bootdata_preserved(__stext_dma);
 104 unsigned long __bootdata_preserved(__etext_dma);
 105 unsigned long __bootdata_preserved(__sdma);
 106 unsigned long __bootdata_preserved(__edma);
 107 unsigned long __bootdata_preserved(__kaslr_offset);
 108 unsigned int __bootdata_preserved(zlib_dfltcc_support);
 109 EXPORT_SYMBOL(zlib_dfltcc_support);
 110 u64 __bootdata_preserved(stfle_fac_list[16]);
 111 EXPORT_SYMBOL(stfle_fac_list);
 112 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 113
 114 unsigned long VMALLOC_START;
 115 EXPORT_SYMBOL(VMALLOC_START);
 116
 117 unsigned long VMALLOC_END;
 118 EXPORT_SYMBOL(VMALLOC_END);
 119
 120 struct page *vmemmap;
 121 EXPORT_SYMBOL(vmemmap);
 122 unsigned long vmemmap_size;
 123
 124 unsigned long MODULES_VADDR;
 125 unsigned long MODULES_END;
 126
 127 /* An array with a pointer to the lowcore of every CPU. */
 128 struct lowcore *lowcore_ptr[NR_CPUS];
 129 EXPORT_SYMBOL(lowcore_ptr);
 130
 131 /*
 132  * The Write Back bit position in the physaddr is given by the SLPC PCI.
 133  * Leaving the mask zero always uses write through which is safe
 134  */
 135 unsigned long mio_wb_bit_mask __ro_after_init;
 136
 137 /*
 138  * This is set up by the setup-routine at boot-time
 139  * for S390 need to find out, what we have to setup
 140  * using address 0x10400 ...
 141  */
 142
 143 #include <asm/setup.h>
 144
 145 /*
 146  * condev= and conmode= setup parameter.
 147  */
 148
 149 static int __init condev_setup(char *str)
 150 {
 151         int vdev;
 152
 153         vdev = simple_strtoul(str, &str, 0);
 154         if (vdev >= 0 && vdev < 65536) {
 155                 console_devno = vdev;
 156                 console_irq = -1;
 157         }
 158         return 1;
 159 }
 160
 161 __setup("condev=", condev_setup);
 162
 163 static void __init set_preferred_console(void)
 164 {
 165         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 166                 add_preferred_console("ttyS", 0, NULL);
 167         else if (CONSOLE_IS_3270)
 168                 add_preferred_console("tty3270", 0, NULL);
 169         else if (CONSOLE_IS_VT220)
 170                 add_preferred_console("ttysclp", 0, NULL);
 171         else if (CONSOLE_IS_HVC)
 172                 add_preferred_console("hvc", 0, NULL);
 173 }
 174
 175 static int __init conmode_setup(char *str)
 176 {
 177 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 178         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 179                 SET_CONSOLE_SCLP;
 180 #endif
 181 #if defined(CONFIG_TN3215_CONSOLE)
 182         if (!strcmp(str, "3215"))
 183                 SET_CONSOLE_3215;
 184 #endif
 185 #if defined(CONFIG_TN3270_CONSOLE)
 186         if (!strcmp(str, "3270"))
 187                 SET_CONSOLE_3270;
 188 #endif
 189         set_preferred_console();
 190         return 1;
 191 }
 192
 193 __setup("conmode=", conmode_setup);
 194
 195 static void __init conmode_default(void)
 196 {
 197         char query_buffer[1024];
 198         char *ptr;
 199
 200         if (MACHINE_IS_VM) {
 201                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 202                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 203                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 204                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 205                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 206                 ptr = strstr(query_buffer, "CONMODE");
 207                 /*
 208                  * Set the conmode to 3215 so that the device recognition
 209                  * will set the cu_type of the console to 3215. If the
 210                  * conmode is 3270 and we don't set it back then both
 211                  * 3215 and the 3270 driver will try to access the console
 212                  * device (3215 as console and 3270 as normal tty).
 213                  */
 214                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 215                 if (ptr == NULL) {
 216 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 217                         SET_CONSOLE_SCLP;
 218 #endif
 219                         return;
 220                 }
 221                 if (str_has_prefix(ptr + 8, "3270")) {
 222 #if defined(CONFIG_TN3270_CONSOLE)
 223                         SET_CONSOLE_3270;
 224 #elif defined(CONFIG_TN3215_CONSOLE)
 225                         SET_CONSOLE_3215;
 226 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 227                         SET_CONSOLE_SCLP;
 228 #endif
 229                 } else if (str_has_prefix(ptr + 8, "3215")) {
 230 #if defined(CONFIG_TN3215_CONSOLE)
 231                         SET_CONSOLE_3215;
 232 #elif defined(CONFIG_TN3270_CONSOLE)
 233                         SET_CONSOLE_3270;
 234 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 235                         SET_CONSOLE_SCLP;
 236 #endif
 237                 }
 238         } else if (MACHINE_IS_KVM) {
 239                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 240                         SET_CONSOLE_VT220;
 241                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 242                         SET_CONSOLE_SCLP;
 243                 else
 244                         SET_CONSOLE_HVC;
 245         } else {
 246 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 247                 SET_CONSOLE_SCLP;
 248 #endif
 249         }
 250 }
 251
 252 #ifdef CONFIG_CRASH_DUMP
 253 static void __init setup_zfcpdump(void)
 254 {
 255         if (!is_ipl_type_dump())
 256                 return;
 257         if (OLDMEM_BASE)
 258                 return;
 259         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 260         console_loglevel = 2;
 261 }
 262 #else
 263 static inline void setup_zfcpdump(void) {}
 264 #endif /* CONFIG_CRASH_DUMP */
 265
 266  /*
 267  * Reboot, halt and power_off stubs. They just call _machine_restart,
 268  * _machine_halt or _machine_power_off.
 269  */
 270
 271 void machine_restart(char *command)
 272 {
 273         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 274                 /*
 275                  * Only unblank the console if we are called in enabled
 276                  * context or a bust_spinlocks cleared the way for us.
 277                  */
 278                 console_unblank();
 279         _machine_restart(command);
 280 }
 281
 282 void machine_halt(void)
 283 {
 284         if (!in_interrupt() || oops_in_progress)
 285                 /*
 286                  * Only unblank the console if we are called in enabled
 287                  * context or a bust_spinlocks cleared the way for us.
 288                  */
 289                 console_unblank();
 290         _machine_halt();
 291 }
 292
 293 void machine_power_off(void)
 294 {
 295         if (!in_interrupt() || oops_in_progress)
 296                 /*
 297                  * Only unblank the console if we are called in enabled
 298                  * context or a bust_spinlocks cleared the way for us.
 299                  */
 300                 console_unblank();
 301         _machine_power_off();
 302 }
 303
 304 /*
 305  * Dummy power off function.
 306  */
 307 void (*pm_power_off)(void) = machine_power_off;
 308 EXPORT_SYMBOL_GPL(pm_power_off);
 309
 310 void *restart_stack;
 311
 312 unsigned long stack_alloc(void)
 313 {
 314 #ifdef CONFIG_VMAP_STACK
 315         return (unsigned long)__vmalloc_node(THREAD_SIZE, THREAD_SIZE,
 316                         THREADINFO_GFP, NUMA_NO_NODE,
 317                         __builtin_return_address(0));
 318 #else
 319         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 320 #endif
 321 }
 322
 323 void stack_free(unsigned long stack)
 324 {
 325 #ifdef CONFIG_VMAP_STACK
 326         vfree((void *) stack);
 327 #else
 328         free_pages(stack, THREAD_SIZE_ORDER);
 329 #endif
 330 }
 331
 332 int __init arch_early_irq_init(void)
 333 {
 334         unsigned long stack;
 335
 336         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 337         if (!stack)
 338                 panic("Couldn't allocate async stack");
 339         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 340         return 0;
 341 }
 342
 343 void __init arch_call_rest_init(void)
 344 {
 345         unsigned long stack;
 346
 347         stack = stack_alloc();
 348         if (!stack)
 349                 panic("Couldn't allocate kernel stack");
 350         current->stack = (void *) stack;
 351 #ifdef CONFIG_VMAP_STACK
 352         current->stack_vm_area = (void *) stack;
 353 #endif
 354         set_task_stack_end_magic(current);
 355         stack += STACK_INIT_OFFSET;
 356         S390_lowcore.kernel_stack = stack;
 357         CALL_ON_STACK_NORETURN(rest_init, stack);
 358 }
 359
 360 static void __init setup_lowcore_dat_off(void)
 361 {
 362         unsigned long int_psw_mask = PSW_KERNEL_BITS;
 363         unsigned long mcck_stack;
 364         struct lowcore *lc;
 365
 366         if (IS_ENABLED(CONFIG_KASAN))
 367                 int_psw_mask |= PSW_MASK_DAT;
 368
 369         /*
 370          * Setup lowcore for boot cpu
 371          */
 372         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 373         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 374         if (!lc)
 375                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 376                       __func__, sizeof(*lc), sizeof(*lc));
 377
 378         lc->restart_psw.mask = PSW_KERNEL_BITS;
 379         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 380         lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 381         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 382         lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 383         lc->svc_new_psw.addr = (unsigned long) system_call;
 384         lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 385         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 386         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 387         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 388         lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 389         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 390         lc->clock_comparator = clock_comparator_max;
 391         lc->nodat_stack = ((unsigned long) &init_thread_union)
 392                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 393         lc->current_task = (unsigned long)&init_task;
 394         lc->lpp = LPP_MAGIC;
 395         lc->machine_flags = S390_lowcore.machine_flags;
 396         lc->preempt_count = S390_lowcore.preempt_count;
 397         nmi_alloc_boot_cpu(lc);
 398         lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 399         lc->exit_timer = S390_lowcore.exit_timer;
 400         lc->user_timer = S390_lowcore.user_timer;
 401         lc->system_timer = S390_lowcore.system_timer;
 402         lc->steal_timer = S390_lowcore.steal_timer;
 403         lc->last_update_timer = S390_lowcore.last_update_timer;
 404         lc->last_update_clock = S390_lowcore.last_update_clock;
 405
 406         /*
 407          * Allocate the global restart stack which is the same for
 408          * all CPUs in cast *one* of them does a PSW restart.
 409          */
 410         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 411         if (!restart_stack)
 412                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 413                       __func__, THREAD_SIZE, THREAD_SIZE);
 414         restart_stack += STACK_INIT_OFFSET;
 415
 416         /*
 417          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 418          * restart data to the absolute zero lowcore. This is necessary if
 419          * PSW restart is done on an offline CPU that has lowcore zero.
 420          */
 421         lc->restart_stack = (unsigned long) restart_stack;
 422         lc->restart_fn = (unsigned long) do_restart;
 423         lc->restart_data = 0;
 424         lc->restart_source = -1UL;
 425
 426         mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 427         if (!mcck_stack)
 428                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 429                       __func__, THREAD_SIZE, THREAD_SIZE);
 430         lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 431
 432         /* Setup absolute zero lowcore */
 433         mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
 434         mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
 435         mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
 436         mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
 437         mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 438
 439         lc->spinlock_lockval = arch_spin_lockval(0);
 440         lc->spinlock_index = 0;
 441         arch_spin_lock_setup(0);
 442         lc->br_r1_trampoline = 0x07f1;  /* br %r1 */
 443         lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 444         lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 445
 446         set_prefix((u32)(unsigned long) lc);
 447         lowcore_ptr[0] = lc;
 448 }
 449
 450 static void __init setup_lowcore_dat_on(void)
 451 {
 452         __ctl_clear_bit(0, 28);
 453         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 454         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 455         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 456         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 457         __ctl_set_bit(0, 28);
 458 }
 459
 460 static struct resource code_resource = {
 461         .name  = "Kernel code",
 462         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 463 };
 464
 465 static struct resource data_resource = {
 466         .name = "Kernel data",
 467         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 468 };
 469
 470 static struct resource bss_resource = {
 471         .name = "Kernel bss",
 472         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 473 };
 474
 475 static struct resource __initdata *standard_resources[] = {
 476         &code_resource,
 477         &data_resource,
 478         &bss_resource,
 479 };
 480
 481 static void __init setup_resources(void)
 482 {
 483         struct resource *res, *std_res, *sub_res;
 484         phys_addr_t start, end;
 485         int j;
 486         u64 i;
 487
 488         code_resource.start = (unsigned long) _text;
 489         code_resource.end = (unsigned long) _etext - 1;
 490         data_resource.start = (unsigned long) _etext;
 491         data_resource.end = (unsigned long) _edata - 1;
 492         bss_resource.start = (unsigned long) __bss_start;
 493         bss_resource.end = (unsigned long) __bss_stop - 1;
 494
 495         for_each_mem_range(i, &start, &end) {
 496                 res = memblock_alloc(sizeof(*res), 8);
 497                 if (!res)
 498                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 499                               __func__, sizeof(*res), 8);
 500                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 501
 502                 res->name = "System RAM";
 503                 res->start = start;
 504                 /*
 505                  * In memblock, end points to the first byte after the
 506                  * range while in resourses, end points to the last byte in
 507                  * the range.
 508                  */
 509                 res->end = end - 1;
 510                 request_resource(&iomem_resource, res);
 511
 512                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 513                         std_res = standard_resources[j];
 514                         if (std_res->start < res->start ||
 515                             std_res->start > res->end)
 516                                 continue;
 517                         if (std_res->end > res->end) {
 518                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 519                                 if (!sub_res)
 520                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 521                                               __func__, sizeof(*sub_res), 8);
 522                                 *sub_res = *std_res;
 523                                 sub_res->end = res->end;
 524                                 std_res->start = res->end + 1;
 525                                 request_resource(res, sub_res);
 526                         } else {
 527                                 request_resource(res, std_res);
 528                         }
 529                 }
 530         }
 531 #ifdef CONFIG_CRASH_DUMP
 532         /*
 533          * Re-add removed crash kernel memory as reserved memory. This makes
 534          * sure it will be mapped with the identity mapping and struct pages
 535          * will be created, so it can be resized later on.
 536          * However add it later since the crash kernel resource should not be
 537          * part of the System RAM resource.
 538          */
 539         if (crashk_res.end) {
 540                 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
 541                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 542                 insert_resource(&iomem_resource, &crashk_res);
 543         }
 544 #endif
 545 }
 546
 547 static void __init setup_memory_end(void)
 548 {
 549         memblock_remove(ident_map_size, ULONG_MAX);
 550         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 551         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 552 }
 553
 554 #ifdef CONFIG_CRASH_DUMP
 555
 556 /*
 557  * When kdump is enabled, we have to ensure that no memory from the area
 558  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 559  * the crashkernel memory region when kdump is triggered. The crashkernel
 560  * memory region can never get offlined (pages are unmovable).
 561  */
 562 static int kdump_mem_notifier(struct notifier_block *nb,
 563                               unsigned long action, void *data)
 564 {
 565         struct memory_notify *arg = data;
 566
 567         if (action != MEM_GOING_OFFLINE)
 568                 return NOTIFY_OK;
 569         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 570                 return NOTIFY_BAD;
 571         return NOTIFY_OK;
 572 }
 573
 574 static struct notifier_block kdump_mem_nb = {
 575         .notifier_call = kdump_mem_notifier,
 576 };
 577
 578 #endif
 579
 580 /*
 581  * Make sure that the area above identity mapping is protected
 582  */
 583 static void __init reserve_above_ident_map(void)
 584 {
 585         memblock_reserve(ident_map_size, ULONG_MAX);
 586 }
 587
 588 /*
 589  * Reserve memory for kdump kernel to be loaded with kexec
 590  */
 591 static void __init reserve_crashkernel(void)
 592 {
 593 #ifdef CONFIG_CRASH_DUMP
 594         unsigned long long crash_base, crash_size;
 595         phys_addr_t low, high;
 596         int rc;
 597
 598         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 599                                &crash_base);
 600
 601         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 602         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 603         if (rc || crash_size == 0)
 604                 return;
 605
 606         if (memblock.memory.regions[0].size < crash_size) {
 607                 pr_info("crashkernel reservation failed: %s\n",
 608                         "first memory chunk must be at least crashkernel size");
 609                 return;
 610         }
 611
 612         low = crash_base ?: OLDMEM_BASE;
 613         high = low + crash_size;
 614         if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
 615                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 616                 crash_base = low;
 617         } else {
 618                 /* Find suitable area in free memory */
 619                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 620                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 621
 622                 if (crash_base && crash_base < low) {
 623                         pr_info("crashkernel reservation failed: %s\n",
 624                                 "crash_base too low");
 625                         return;
 626                 }
 627                 low = crash_base ?: low;
 628                 crash_base = memblock_find_in_range(low, high, crash_size,
 629                                                     KEXEC_CRASH_MEM_ALIGN);
 630         }
 631
 632         if (!crash_base) {
 633                 pr_info("crashkernel reservation failed: %s\n",
 634                         "no suitable area found");
 635                 return;
 636         }
 637
 638         if (register_memory_notifier(&kdump_mem_nb))
 639                 return;
 640
 641         if (!OLDMEM_BASE && MACHINE_IS_VM)
 642                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 643         crashk_res.start = crash_base;
 644         crashk_res.end = crash_base + crash_size - 1;
 645         memblock_remove(crash_base, crash_size);
 646         pr_info("Reserving %lluMB of memory at %lluMB "
 647                 "for crashkernel (System RAM: %luMB)\n",
 648                 crash_size >> 20, crash_base >> 20,
 649                 (unsigned long)memblock.memory.total_size >> 20);
 650         os_info_crashkernel_add(crash_base, crash_size);
 651 #endif
 652 }
 653
 654 /*
 655  * Reserve the initrd from being used by memblock
 656  */
 657 static void __init reserve_initrd(void)
 658 {
 659 #ifdef CONFIG_BLK_DEV_INITRD
 660         if (!INITRD_START || !INITRD_SIZE)
 661                 return;
 662         initrd_start = INITRD_START;
 663         initrd_end = initrd_start + INITRD_SIZE;
 664         memblock_reserve(INITRD_START, INITRD_SIZE);
 665 #endif
 666 }
 667
 668 /*
 669  * Reserve the memory area used to pass the certificate lists
 670  */
 671 static void __init reserve_certificate_list(void)
 672 {
 673         if (ipl_cert_list_addr)
 674                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 675 }
 676
 677 static void __init reserve_mem_detect_info(void)
 678 {
 679         unsigned long start, size;
 680
 681         get_mem_detect_reserved(&start, &size);
 682         if (size)
 683                 memblock_reserve(start, size);
 684 }
 685
 686 static void __init free_mem_detect_info(void)
 687 {
 688         unsigned long start, size;
 689
 690         get_mem_detect_reserved(&start, &size);
 691         if (size)
 692                 memblock_free(start, size);
 693 }
 694
 695 static const char * __init get_mem_info_source(void)
 696 {
 697         switch (mem_detect.info_source) {
 698         case MEM_DETECT_SCLP_STOR_INFO:
 699                 return "sclp storage info";
 700         case MEM_DETECT_DIAG260:
 701                 return "diag260";
 702         case MEM_DETECT_SCLP_READ_INFO:
 703                 return "sclp read info";
 704         case MEM_DETECT_BIN_SEARCH:
 705                 return "binary search";
 706         }
 707         return "none";
 708 }
 709
 710 static void __init memblock_add_mem_detect_info(void)
 711 {
 712         unsigned long start, end;
 713         int i;
 714
 715         pr_debug("physmem info source: %s (%hhd)\n",
 716                  get_mem_info_source(), mem_detect.info_source);
 717         /* keep memblock lists close to the kernel */
 718         memblock_set_bottom_up(true);
 719         for_each_mem_detect_block(i, &start, &end) {
 720                 memblock_add(start, end - start);
 721                 memblock_physmem_add(start, end - start);
 722         }
 723         memblock_set_bottom_up(false);
 724         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 725         memblock_dump_all();
 726 }
 727
 728 /*
 729  * Check for initrd being in usable memory
 730  */
 731 static void __init check_initrd(void)
 732 {
 733 #ifdef CONFIG_BLK_DEV_INITRD
 734         if (INITRD_START && INITRD_SIZE &&
 735             !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
 736                 pr_err("The initial RAM disk does not fit into the memory\n");
 737                 memblock_free(INITRD_START, INITRD_SIZE);
 738                 initrd_start = initrd_end = 0;
 739         }
 740 #endif
 741 }
 742
 743 /*
 744  * Reserve memory used for lowcore/command line/kernel image.
 745  */
 746 static void __init reserve_kernel(void)
 747 {
 748         unsigned long start_pfn = PFN_UP(__pa(_end));
 749
 750         memblock_reserve(0, HEAD_END);
 751         memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
 752                          - (unsigned long)_stext);
 753         memblock_reserve(__sdma, __edma - __sdma);
 754 }
 755
 756 static void __init setup_memory(void)
 757 {
 758         phys_addr_t start, end;
 759         u64 i;
 760
 761         /*
 762          * Init storage key for present memory
 763          */
 764         for_each_mem_range(i, &start, &end)
 765                 storage_key_init_range(start, end);
 766
 767         psw_set_key(PAGE_DEFAULT_KEY);
 768
 769         /* Only cosmetics */
 770         memblock_enforce_memory_limit(memblock_end_of_DRAM());
 771 }
 772
 773 /*
 774  * Setup hardware capabilities.
 775  */
 776 static int __init setup_hwcaps(void)
 777 {
 778         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 779         struct cpuid cpu_id;
 780         int i;
 781
 782         /*
 783          * The store facility list bits numbers as found in the principles
 784          * of operation are numbered with bit 1UL<<31 as number 0 to
 785          * bit 1UL<<0 as number 31.
 786          *   Bit 0: instructions named N3, "backported" to esa-mode
 787          *   Bit 2: z/Architecture mode is active
 788          *   Bit 7: the store-facility-list-extended facility is installed
 789          *   Bit 17: the message-security assist is installed
 790          *   Bit 19: the long-displacement facility is installed
 791          *   Bit 21: the extended-immediate facility is installed
 792          *   Bit 22: extended-translation facility 3 is installed
 793          *   Bit 30: extended-translation facility 3 enhancement facility
 794          * These get translated to:
 795          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 796          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 797          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 798          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 799          */
 800         for (i = 0; i < 6; i++)
 801                 if (test_facility(stfl_bits[i]))
 802                         elf_hwcap |= 1UL << i;
 803
 804         if (test_facility(22) && test_facility(30))
 805                 elf_hwcap |= HWCAP_S390_ETF3EH;
 806
 807         /*
 808          * Check for additional facilities with store-facility-list-extended.
 809          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 810          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 811          * as stored by stfl, bits 32-xxx contain additional facilities.
 812          * How many facility words are stored depends on the number of
 813          * doublewords passed to the instruction. The additional facilities
 814          * are:
 815          *   Bit 42: decimal floating point facility is installed
 816          *   Bit 44: perform floating point operation facility is installed
 817          * translated to:
 818          *   HWCAP_S390_DFP bit 6 (42 && 44).
 819          */
 820         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 821                 elf_hwcap |= HWCAP_S390_DFP;
 822
 823         /*
 824          * Huge page support HWCAP_S390_HPAGE is bit 7.
 825          */
 826         if (MACHINE_HAS_EDAT1)
 827                 elf_hwcap |= HWCAP_S390_HPAGE;
 828
 829         /*
 830          * 64-bit register support for 31-bit processes
 831          * HWCAP_S390_HIGH_GPRS is bit 9.
 832          */
 833         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 834
 835         /*
 836          * Transactional execution support HWCAP_S390_TE is bit 10.
 837          */
 838         if (MACHINE_HAS_TE)
 839                 elf_hwcap |= HWCAP_S390_TE;
 840
 841         /*
 842          * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
 843          * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
 844          * instead of facility bit 129.
 845          */
 846         if (MACHINE_HAS_VX) {
 847                 elf_hwcap |= HWCAP_S390_VXRS;
 848                 if (test_facility(134))
 849                         elf_hwcap |= HWCAP_S390_VXRS_BCD;
 850                 if (test_facility(135))
 851                         elf_hwcap |= HWCAP_S390_VXRS_EXT;
 852                 if (test_facility(148))
 853                         elf_hwcap |= HWCAP_S390_VXRS_EXT2;
 854                 if (test_facility(152))
 855                         elf_hwcap |= HWCAP_S390_VXRS_PDE;
 856         }
 857         if (test_facility(150))
 858                 elf_hwcap |= HWCAP_S390_SORT;
 859         if (test_facility(151))
 860                 elf_hwcap |= HWCAP_S390_DFLT;
 861
 862         /*
 863          * Guarded storage support HWCAP_S390_GS is bit 12.
 864          */
 865         if (MACHINE_HAS_GS)
 866                 elf_hwcap |= HWCAP_S390_GS;
 867
 868         get_cpu_id(&cpu_id);
 869         add_device_randomness(&cpu_id, sizeof(cpu_id));
 870         switch (cpu_id.machine) {
 871         case 0x2064:
 872         case 0x2066:
 873         default:        /* Use "z900" as default for 64 bit kernels. */
 874                 strcpy(elf_platform, "z900");
 875                 break;
 876         case 0x2084:
 877         case 0x2086:
 878                 strcpy(elf_platform, "z990");
 879                 break;
 880         case 0x2094:
 881         case 0x2096:
 882                 strcpy(elf_platform, "z9-109");
 883                 break;
 884         case 0x2097:
 885         case 0x2098:
 886                 strcpy(elf_platform, "z10");
 887                 break;
 888         case 0x2817:
 889         case 0x2818:
 890                 strcpy(elf_platform, "z196");
 891                 break;
 892         case 0x2827:
 893         case 0x2828:
 894                 strcpy(elf_platform, "zEC12");
 895                 break;
 896         case 0x2964:
 897         case 0x2965:
 898                 strcpy(elf_platform, "z13");
 899                 break;
 900         case 0x3906:
 901         case 0x3907:
 902                 strcpy(elf_platform, "z14");
 903                 break;
 904         case 0x8561:
 905         case 0x8562:
 906                 strcpy(elf_platform, "z15");
 907                 break;
 908         }
 909
 910         /*
 911          * Virtualization support HWCAP_INT_SIE is bit 0.
 912          */
 913         if (sclp.has_sief2)
 914                 int_hwcap |= HWCAP_INT_SIE;
 915
 916         return 0;
 917 }
 918 arch_initcall(setup_hwcaps);
 919
 920 /*
 921  * Add system information as device randomness
 922  */
 923 static void __init setup_randomness(void)
 924 {
 925         struct sysinfo_3_2_2 *vmms;
 926
 927         vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
 928                                                             PAGE_SIZE);
 929         if (!vmms)
 930                 panic("Failed to allocate memory for sysinfo structure\n");
 931
 932         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 933                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 934         memblock_free((unsigned long) vmms, PAGE_SIZE);
 935 }
 936
 937 /*
 938  * Find the correct size for the task_struct. This depends on
 939  * the size of the struct fpu at the end of the thread_struct
 940  * which is embedded in the task_struct.
 941  */
 942 static void __init setup_task_size(void)
 943 {
 944         int task_size = sizeof(struct task_struct);
 945
 946         if (!MACHINE_HAS_VX) {
 947                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 948                 task_size += sizeof(freg_t) * __NUM_FPRS;
 949         }
 950         arch_task_struct_size = task_size;
 951 }
 952
 953 /*
 954  * Issue diagnose 318 to set the control program name and
 955  * version codes.
 956  */
 957 static void __init setup_control_program_code(void)
 958 {
 959         union diag318_info diag318_info = {
 960                 .cpnc = CPNC_LINUX,
 961                 .cpvc = 0,
 962         };
 963
 964         if (!sclp.has_diag318)
 965                 return;
 966
 967         diag_stat_inc(DIAG_STAT_X318);
 968         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 969 }
 970
 971 /*
 972  * Print the component list from the IPL report
 973  */
 974 static void __init log_component_list(void)
 975 {
 976         struct ipl_rb_component_entry *ptr, *end;
 977         char *str;
 978
 979         if (!early_ipl_comp_list_addr)
 980                 return;
 981         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 982                 pr_info("Linux is running with Secure-IPL enabled\n");
 983         else
 984                 pr_info("Linux is running with Secure-IPL disabled\n");
 985         ptr = (void *) early_ipl_comp_list_addr;
 986         end = (void *) ptr + early_ipl_comp_list_size;
 987         pr_info("The IPL report contains the following components:\n");
 988         while (ptr < end) {
 989                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 990                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 991                                 str = "signed, verified";
 992                         else
 993                                 str = "signed, verification failed";
 994                 } else {
 995                         str = "not signed";
 996                 }
 997                 pr_info("%016llx - %016llx (%s)\n",
 998                         ptr->addr, ptr->addr + ptr->len, str);
 999                 ptr++;
1000         }
1001 }
1002
1003 /*
1004  * Setup function called from init/main.c just after the banner
1005  * was printed.
1006  */
1007
1008 void __init setup_arch(char **cmdline_p)
1009 {
1010         /*
1011          * print what head.S has found out about the machine
1012          */
1013         if (MACHINE_IS_VM)
1014                 pr_info("Linux is running as a z/VM "
1015                         "guest operating system in 64-bit mode\n");
1016         else if (MACHINE_IS_KVM)
1017                 pr_info("Linux is running under KVM in 64-bit mode\n");
1018         else if (MACHINE_IS_LPAR)
1019                 pr_info("Linux is running natively in 64-bit mode\n");
1020         else
1021                 pr_info("Linux is running as a guest in 64-bit mode\n");
1022
1023         log_component_list();
1024
1025         /* Have one command line that is parsed and saved in /proc/cmdline */
1026         /* boot_command_line has been already set up in early.c */
1027         *cmdline_p = boot_command_line;
1028
1029         ROOT_DEV = Root_RAM0;
1030
1031         setup_initial_init_mm(_text, _etext, _edata, _end);
1032
1033         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1034                 nospec_auto_detect();
1035
1036         jump_label_init();
1037         parse_early_param();
1038 #ifdef CONFIG_CRASH_DUMP
1039         /* Deactivate elfcorehdr= kernel parameter */
1040         elfcorehdr_addr = ELFCORE_ADDR_MAX;
1041 #endif
1042
1043         os_info_init();
1044         setup_ipl();
1045         setup_task_size();
1046         setup_control_program_code();
1047
1048         /* Do some memory reservations *before* memory is added to memblock */
1049         reserve_above_ident_map();
1050         reserve_kernel();
1051         reserve_initrd();
1052         reserve_certificate_list();
1053         reserve_mem_detect_info();
1054         memblock_allow_resize();
1055
1056         /* Get information about *all* installed memory */
1057         memblock_add_mem_detect_info();
1058
1059         free_mem_detect_info();
1060
1061         setup_uv();
1062         setup_memory_end();
1063         setup_memory();
1064         dma_contiguous_reserve(ident_map_size);
1065         vmcp_cma_reserve();
1066         if (MACHINE_HAS_EDAT2)
1067                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1068
1069         check_initrd();
1070         reserve_crashkernel();
1071 #ifdef CONFIG_CRASH_DUMP
1072         /*
1073          * Be aware that smp_save_dump_cpus() triggers a system reset.
1074          * Therefore CPU and device initialization should be done afterwards.
1075          */
1076         smp_save_dump_cpus();
1077 #endif
1078
1079         setup_resources();
1080         setup_lowcore_dat_off();
1081         smp_fill_possible_mask();
1082         cpu_detect_mhz_feature();
1083         cpu_init();
1084         numa_setup();
1085         smp_detect_cpus();
1086         topology_init_early();
1087
1088         /*
1089          * Create kernel page tables and switch to virtual addressing.
1090          */
1091         paging_init();
1092
1093         /*
1094          * After paging_init created the kernel page table, the new PSWs
1095          * in lowcore can now run with DAT enabled.
1096          */
1097         setup_lowcore_dat_on();
1098
1099         /* Setup default console */
1100         conmode_default();
1101         set_preferred_console();
1102
1103         apply_alternative_instructions();
1104         if (IS_ENABLED(CONFIG_EXPOLINE))
1105                 nospec_init_branches();
1106
1107         /* Setup zfcp/nvme dump support */
1108         setup_zfcpdump();
1109
1110         /* Add system specific data to the random pool */
1111         setup_randomness();
1112 }