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 #include <linux/kmemleak.h>
  54
  55 #include <asm/boot_data.h>
  56 #include <asm/ipl.h>
  57 #include <asm/facility.h>
  58 #include <asm/smp.h>
  59 #include <asm/mmu_context.h>
  60 #include <asm/cpcmd.h>
  61 #include <asm/lowcore.h>
  62 #include <asm/nmi.h>
  63 #include <asm/irq.h>
  64 #include <asm/page.h>
  65 #include <asm/ptrace.h>
  66 #include <asm/sections.h>
  67 #include <asm/ebcdic.h>
  68 #include <asm/diag.h>
  69 #include <asm/os_info.h>
  70 #include <asm/sclp.h>
  71 #include <asm/stacktrace.h>
  72 #include <asm/sysinfo.h>
  73 #include <asm/numa.h>
  74 #include <asm/alternative.h>
  75 #include <asm/nospec-branch.h>
  76 #include <asm/mem_detect.h>
  77 #include <asm/uv.h>
  78 #include <asm/asm-offsets.h>
  79 #include "entry.h"
  80
  81 /*
  82  * Machine setup..
  83  */
  84 unsigned int console_mode = 0;
  85 EXPORT_SYMBOL(console_mode);
  86
  87 unsigned int console_devno = -1;
  88 EXPORT_SYMBOL(console_devno);
  89
  90 unsigned int console_irq = -1;
  91 EXPORT_SYMBOL(console_irq);
  92
  93 /*
  94  * Some code and data needs to stay below 2 GB, even when the kernel would be
  95  * relocated above 2 GB, because it has to use 31 bit addresses.
  96  * Such code and data is part of the .amode31 section.
  97  */
  98 unsigned long __amode31_ref __samode31 = __pa(&_samode31);
  99 unsigned long __amode31_ref __eamode31 = __pa(&_eamode31);
 100 unsigned long __amode31_ref __stext_amode31 = __pa(&_stext_amode31);
 101 unsigned long __amode31_ref __etext_amode31 = __pa(&_etext_amode31);
 102 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
 103 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
 104
 105 /*
 106  * Control registers CR2, CR5 and CR15 are initialized with addresses
 107  * of tables that must be placed below 2G which is handled by the AMODE31
 108  * sections.
 109  * Because the AMODE31 sections are relocated below 2G at startup,
 110  * the content of control registers CR2, CR5 and CR15 must be updated
 111  * with new addresses after the relocation. The initial initialization of
 112  * control registers occurs in head64.S and then gets updated again after AMODE31
 113  * relocation. We must access the relevant AMODE31 tables indirectly via
 114  * pointers placed in the .amode31.refs linker section. Those pointers get
 115  * updated automatically during AMODE31 relocation and always contain a valid
 116  * address within AMODE31 sections.
 117  */
 118
 119 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
 120
 121 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
 122         [1] = 0xffffffffffffffff
 123 };
 124
 125 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
 126         0x80000000, 0, 0, 0,
 127         0x80000000, 0, 0, 0,
 128         0x80000000, 0, 0, 0,
 129         0x80000000, 0, 0, 0,
 130         0x80000000, 0, 0, 0,
 131         0x80000000, 0, 0, 0,
 132         0x80000000, 0, 0, 0,
 133         0x80000000, 0, 0, 0
 134 };
 135
 136 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
 137         0, 0, 0x89000000, 0,
 138         0, 0, 0x8a000000, 0
 139 };
 140
 141 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
 142 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
 143 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
 144 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
 145
 146 int __bootdata(noexec_disabled);
 147 unsigned long __bootdata(ident_map_size);
 148 struct mem_detect_info __bootdata(mem_detect);
 149 struct initrd_data __bootdata(initrd_data);
 150
 151 unsigned long __bootdata_preserved(__kaslr_offset);
 152 unsigned int __bootdata_preserved(zlib_dfltcc_support);
 153 EXPORT_SYMBOL(zlib_dfltcc_support);
 154 u64 __bootdata_preserved(stfle_fac_list[16]);
 155 EXPORT_SYMBOL(stfle_fac_list);
 156 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 157 struct oldmem_data __bootdata_preserved(oldmem_data);
 158
 159 unsigned long VMALLOC_START;
 160 EXPORT_SYMBOL(VMALLOC_START);
 161
 162 unsigned long VMALLOC_END;
 163 EXPORT_SYMBOL(VMALLOC_END);
 164
 165 struct page *vmemmap;
 166 EXPORT_SYMBOL(vmemmap);
 167 unsigned long vmemmap_size;
 168
 169 unsigned long MODULES_VADDR;
 170 unsigned long MODULES_END;
 171
 172 /* An array with a pointer to the lowcore of every CPU. */
 173 struct lowcore *lowcore_ptr[NR_CPUS];
 174 EXPORT_SYMBOL(lowcore_ptr);
 175
 176 /*
 177  * The Write Back bit position in the physaddr is given by the SLPC PCI.
 178  * Leaving the mask zero always uses write through which is safe
 179  */
 180 unsigned long mio_wb_bit_mask __ro_after_init;
 181
 182 /*
 183  * This is set up by the setup-routine at boot-time
 184  * for S390 need to find out, what we have to setup
 185  * using address 0x10400 ...
 186  */
 187
 188 #include <asm/setup.h>
 189
 190 /*
 191  * condev= and conmode= setup parameter.
 192  */
 193
 194 static int __init condev_setup(char *str)
 195 {
 196         int vdev;
 197
 198         vdev = simple_strtoul(str, &str, 0);
 199         if (vdev >= 0 && vdev < 65536) {
 200                 console_devno = vdev;
 201                 console_irq = -1;
 202         }
 203         return 1;
 204 }
 205
 206 __setup("condev=", condev_setup);
 207
 208 static void __init set_preferred_console(void)
 209 {
 210         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 211                 add_preferred_console("ttyS", 0, NULL);
 212         else if (CONSOLE_IS_3270)
 213                 add_preferred_console("tty3270", 0, NULL);
 214         else if (CONSOLE_IS_VT220)
 215                 add_preferred_console("ttysclp", 0, NULL);
 216         else if (CONSOLE_IS_HVC)
 217                 add_preferred_console("hvc", 0, NULL);
 218 }
 219
 220 static int __init conmode_setup(char *str)
 221 {
 222 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 223         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 224                 SET_CONSOLE_SCLP;
 225 #endif
 226 #if defined(CONFIG_TN3215_CONSOLE)
 227         if (!strcmp(str, "3215"))
 228                 SET_CONSOLE_3215;
 229 #endif
 230 #if defined(CONFIG_TN3270_CONSOLE)
 231         if (!strcmp(str, "3270"))
 232                 SET_CONSOLE_3270;
 233 #endif
 234         set_preferred_console();
 235         return 1;
 236 }
 237
 238 __setup("conmode=", conmode_setup);
 239
 240 static void __init conmode_default(void)
 241 {
 242         char query_buffer[1024];
 243         char *ptr;
 244
 245         if (MACHINE_IS_VM) {
 246                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 247                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 248                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 249                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 250                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 251                 ptr = strstr(query_buffer, "CONMODE");
 252                 /*
 253                  * Set the conmode to 3215 so that the device recognition
 254                  * will set the cu_type of the console to 3215. If the
 255                  * conmode is 3270 and we don't set it back then both
 256                  * 3215 and the 3270 driver will try to access the console
 257                  * device (3215 as console and 3270 as normal tty).
 258                  */
 259                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 260                 if (ptr == NULL) {
 261 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 262                         SET_CONSOLE_SCLP;
 263 #endif
 264                         return;
 265                 }
 266                 if (str_has_prefix(ptr + 8, "3270")) {
 267 #if defined(CONFIG_TN3270_CONSOLE)
 268                         SET_CONSOLE_3270;
 269 #elif defined(CONFIG_TN3215_CONSOLE)
 270                         SET_CONSOLE_3215;
 271 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 272                         SET_CONSOLE_SCLP;
 273 #endif
 274                 } else if (str_has_prefix(ptr + 8, "3215")) {
 275 #if defined(CONFIG_TN3215_CONSOLE)
 276                         SET_CONSOLE_3215;
 277 #elif defined(CONFIG_TN3270_CONSOLE)
 278                         SET_CONSOLE_3270;
 279 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 280                         SET_CONSOLE_SCLP;
 281 #endif
 282                 }
 283         } else if (MACHINE_IS_KVM) {
 284                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 285                         SET_CONSOLE_VT220;
 286                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 287                         SET_CONSOLE_SCLP;
 288                 else
 289                         SET_CONSOLE_HVC;
 290         } else {
 291 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 292                 SET_CONSOLE_SCLP;
 293 #endif
 294         }
 295 }
 296
 297 #ifdef CONFIG_CRASH_DUMP
 298 static void __init setup_zfcpdump(void)
 299 {
 300         if (!is_ipl_type_dump())
 301                 return;
 302         if (oldmem_data.start)
 303                 return;
 304         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 305         console_loglevel = 2;
 306 }
 307 #else
 308 static inline void setup_zfcpdump(void) {}
 309 #endif /* CONFIG_CRASH_DUMP */
 310
 311  /*
 312  * Reboot, halt and power_off stubs. They just call _machine_restart,
 313  * _machine_halt or _machine_power_off.
 314  */
 315
 316 void machine_restart(char *command)
 317 {
 318         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 319                 /*
 320                  * Only unblank the console if we are called in enabled
 321                  * context or a bust_spinlocks cleared the way for us.
 322                  */
 323                 console_unblank();
 324         _machine_restart(command);
 325 }
 326
 327 void machine_halt(void)
 328 {
 329         if (!in_interrupt() || oops_in_progress)
 330                 /*
 331                  * Only unblank the console if we are called in enabled
 332                  * context or a bust_spinlocks cleared the way for us.
 333                  */
 334                 console_unblank();
 335         _machine_halt();
 336 }
 337
 338 void machine_power_off(void)
 339 {
 340         if (!in_interrupt() || oops_in_progress)
 341                 /*
 342                  * Only unblank the console if we are called in enabled
 343                  * context or a bust_spinlocks cleared the way for us.
 344                  */
 345                 console_unblank();
 346         _machine_power_off();
 347 }
 348
 349 /*
 350  * Dummy power off function.
 351  */
 352 void (*pm_power_off)(void) = machine_power_off;
 353 EXPORT_SYMBOL_GPL(pm_power_off);
 354
 355 void *restart_stack;
 356
 357 unsigned long stack_alloc(void)
 358 {
 359 #ifdef CONFIG_VMAP_STACK
 360         void *ret;
 361
 362         ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
 363                              NUMA_NO_NODE, __builtin_return_address(0));
 364         kmemleak_not_leak(ret);
 365         return (unsigned long)ret;
 366 #else
 367         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 368 #endif
 369 }
 370
 371 void stack_free(unsigned long stack)
 372 {
 373 #ifdef CONFIG_VMAP_STACK
 374         vfree((void *) stack);
 375 #else
 376         free_pages(stack, THREAD_SIZE_ORDER);
 377 #endif
 378 }
 379
 380 int __init arch_early_irq_init(void)
 381 {
 382         unsigned long stack;
 383
 384         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 385         if (!stack)
 386                 panic("Couldn't allocate async stack");
 387         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 388         return 0;
 389 }
 390
 391 void __init arch_call_rest_init(void)
 392 {
 393         unsigned long stack;
 394
 395         stack = stack_alloc();
 396         if (!stack)
 397                 panic("Couldn't allocate kernel stack");
 398         current->stack = (void *) stack;
 399 #ifdef CONFIG_VMAP_STACK
 400         current->stack_vm_area = (void *) stack;
 401 #endif
 402         set_task_stack_end_magic(current);
 403         stack += STACK_INIT_OFFSET;
 404         S390_lowcore.kernel_stack = stack;
 405         call_on_stack_noreturn(rest_init, stack);
 406 }
 407
 408 static void __init setup_lowcore_dat_off(void)
 409 {
 410         unsigned long int_psw_mask = PSW_KERNEL_BITS;
 411         unsigned long mcck_stack;
 412         struct lowcore *lc;
 413
 414         if (IS_ENABLED(CONFIG_KASAN))
 415                 int_psw_mask |= PSW_MASK_DAT;
 416
 417         /*
 418          * Setup lowcore for boot cpu
 419          */
 420         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 421         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 422         if (!lc)
 423                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 424                       __func__, sizeof(*lc), sizeof(*lc));
 425
 426         lc->restart_psw.mask = PSW_KERNEL_BITS;
 427         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 428         lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 429         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 430         lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 431         lc->svc_new_psw.addr = (unsigned long) system_call;
 432         lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 433         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 434         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 435         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 436         lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 437         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 438         lc->clock_comparator = clock_comparator_max;
 439         lc->nodat_stack = ((unsigned long) &init_thread_union)
 440                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 441         lc->current_task = (unsigned long)&init_task;
 442         lc->lpp = LPP_MAGIC;
 443         lc->machine_flags = S390_lowcore.machine_flags;
 444         lc->preempt_count = S390_lowcore.preempt_count;
 445         nmi_alloc_boot_cpu(lc);
 446         lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 447         lc->exit_timer = S390_lowcore.exit_timer;
 448         lc->user_timer = S390_lowcore.user_timer;
 449         lc->system_timer = S390_lowcore.system_timer;
 450         lc->steal_timer = S390_lowcore.steal_timer;
 451         lc->last_update_timer = S390_lowcore.last_update_timer;
 452         lc->last_update_clock = S390_lowcore.last_update_clock;
 453
 454         /*
 455          * Allocate the global restart stack which is the same for
 456          * all CPUs in cast *one* of them does a PSW restart.
 457          */
 458         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 459         if (!restart_stack)
 460                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 461                       __func__, THREAD_SIZE, THREAD_SIZE);
 462         restart_stack += STACK_INIT_OFFSET;
 463
 464         /*
 465          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 466          * restart data to the absolute zero lowcore. This is necessary if
 467          * PSW restart is done on an offline CPU that has lowcore zero.
 468          */
 469         lc->restart_stack = (unsigned long) restart_stack;
 470         lc->restart_fn = (unsigned long) do_restart;
 471         lc->restart_data = 0;
 472         lc->restart_source = -1U;
 473
 474         mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 475         if (!mcck_stack)
 476                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 477                       __func__, THREAD_SIZE, THREAD_SIZE);
 478         lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 479
 480         /* Setup absolute zero lowcore */
 481         mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
 482         mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
 483         mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
 484         mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
 485         mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 486
 487         lc->spinlock_lockval = arch_spin_lockval(0);
 488         lc->spinlock_index = 0;
 489         arch_spin_lock_setup(0);
 490         lc->br_r1_trampoline = 0x07f1;  /* br %r1 */
 491         lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 492         lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 493         lc->preempt_count = PREEMPT_DISABLED;
 494
 495         set_prefix((u32)(unsigned long) lc);
 496         lowcore_ptr[0] = lc;
 497 }
 498
 499 static void __init setup_lowcore_dat_on(void)
 500 {
 501         struct lowcore *lc = lowcore_ptr[0];
 502
 503         __ctl_clear_bit(0, 28);
 504         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 505         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 506         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 507         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 508         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 509         __ctl_set_bit(0, 28);
 510         mem_assign_absolute(S390_lowcore.restart_flags, RESTART_FLAG_CTLREGS);
 511         mem_assign_absolute(S390_lowcore.program_new_psw, lc->program_new_psw);
 512         memcpy_absolute(&S390_lowcore.cregs_save_area, lc->cregs_save_area,
 513                         sizeof(S390_lowcore.cregs_save_area));
 514 }
 515
 516 static struct resource code_resource = {
 517         .name  = "Kernel code",
 518         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 519 };
 520
 521 static struct resource data_resource = {
 522         .name = "Kernel data",
 523         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 524 };
 525
 526 static struct resource bss_resource = {
 527         .name = "Kernel bss",
 528         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 529 };
 530
 531 static struct resource __initdata *standard_resources[] = {
 532         &code_resource,
 533         &data_resource,
 534         &bss_resource,
 535 };
 536
 537 static void __init setup_resources(void)
 538 {
 539         struct resource *res, *std_res, *sub_res;
 540         phys_addr_t start, end;
 541         int j;
 542         u64 i;
 543
 544         code_resource.start = (unsigned long) _text;
 545         code_resource.end = (unsigned long) _etext - 1;
 546         data_resource.start = (unsigned long) _etext;
 547         data_resource.end = (unsigned long) _edata - 1;
 548         bss_resource.start = (unsigned long) __bss_start;
 549         bss_resource.end = (unsigned long) __bss_stop - 1;
 550
 551         for_each_mem_range(i, &start, &end) {
 552                 res = memblock_alloc(sizeof(*res), 8);
 553                 if (!res)
 554                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 555                               __func__, sizeof(*res), 8);
 556                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 557
 558                 res->name = "System RAM";
 559                 res->start = start;
 560                 /*
 561                  * In memblock, end points to the first byte after the
 562                  * range while in resourses, end points to the last byte in
 563                  * the range.
 564                  */
 565                 res->end = end - 1;
 566                 request_resource(&iomem_resource, res);
 567
 568                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 569                         std_res = standard_resources[j];
 570                         if (std_res->start < res->start ||
 571                             std_res->start > res->end)
 572                                 continue;
 573                         if (std_res->end > res->end) {
 574                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 575                                 if (!sub_res)
 576                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 577                                               __func__, sizeof(*sub_res), 8);
 578                                 *sub_res = *std_res;
 579                                 sub_res->end = res->end;
 580                                 std_res->start = res->end + 1;
 581                                 request_resource(res, sub_res);
 582                         } else {
 583                                 request_resource(res, std_res);
 584                         }
 585                 }
 586         }
 587 #ifdef CONFIG_CRASH_DUMP
 588         /*
 589          * Re-add removed crash kernel memory as reserved memory. This makes
 590          * sure it will be mapped with the identity mapping and struct pages
 591          * will be created, so it can be resized later on.
 592          * However add it later since the crash kernel resource should not be
 593          * part of the System RAM resource.
 594          */
 595         if (crashk_res.end) {
 596                 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
 597                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 598                 insert_resource(&iomem_resource, &crashk_res);
 599         }
 600 #endif
 601 }
 602
 603 static void __init setup_memory_end(void)
 604 {
 605         memblock_remove(ident_map_size, ULONG_MAX);
 606         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 607         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 608 }
 609
 610 #ifdef CONFIG_CRASH_DUMP
 611
 612 /*
 613  * When kdump is enabled, we have to ensure that no memory from the area
 614  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 615  * the crashkernel memory region when kdump is triggered. The crashkernel
 616  * memory region can never get offlined (pages are unmovable).
 617  */
 618 static int kdump_mem_notifier(struct notifier_block *nb,
 619                               unsigned long action, void *data)
 620 {
 621         struct memory_notify *arg = data;
 622
 623         if (action != MEM_GOING_OFFLINE)
 624                 return NOTIFY_OK;
 625         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 626                 return NOTIFY_BAD;
 627         return NOTIFY_OK;
 628 }
 629
 630 static struct notifier_block kdump_mem_nb = {
 631         .notifier_call = kdump_mem_notifier,
 632 };
 633
 634 #endif
 635
 636 /*
 637  * Make sure that the area above identity mapping is protected
 638  */
 639 static void __init reserve_above_ident_map(void)
 640 {
 641         memblock_reserve(ident_map_size, ULONG_MAX);
 642 }
 643
 644 /*
 645  * Reserve memory for kdump kernel to be loaded with kexec
 646  */
 647 static void __init reserve_crashkernel(void)
 648 {
 649 #ifdef CONFIG_CRASH_DUMP
 650         unsigned long long crash_base, crash_size;
 651         phys_addr_t low, high;
 652         int rc;
 653
 654         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 655                                &crash_base);
 656
 657         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 658         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 659         if (rc || crash_size == 0)
 660                 return;
 661
 662         if (memblock.memory.regions[0].size < crash_size) {
 663                 pr_info("crashkernel reservation failed: %s\n",
 664                         "first memory chunk must be at least crashkernel size");
 665                 return;
 666         }
 667
 668         low = crash_base ?: oldmem_data.start;
 669         high = low + crash_size;
 670         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 671                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 672                 crash_base = low;
 673         } else {
 674                 /* Find suitable area in free memory */
 675                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 676                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 677
 678                 if (crash_base && crash_base < low) {
 679                         pr_info("crashkernel reservation failed: %s\n",
 680                                 "crash_base too low");
 681                         return;
 682                 }
 683                 low = crash_base ?: low;
 684                 crash_base = memblock_phys_alloc_range(crash_size,
 685                                                        KEXEC_CRASH_MEM_ALIGN,
 686                                                        low, high);
 687         }
 688
 689         if (!crash_base) {
 690                 pr_info("crashkernel reservation failed: %s\n",
 691                         "no suitable area found");
 692                 return;
 693         }
 694
 695         if (register_memory_notifier(&kdump_mem_nb)) {
 696                 memblock_free(crash_base, crash_size);
 697                 return;
 698         }
 699
 700         if (!oldmem_data.start && MACHINE_IS_VM)
 701                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 702         crashk_res.start = crash_base;
 703         crashk_res.end = crash_base + crash_size - 1;
 704         memblock_remove(crash_base, crash_size);
 705         pr_info("Reserving %lluMB of memory at %lluMB "
 706                 "for crashkernel (System RAM: %luMB)\n",
 707                 crash_size >> 20, crash_base >> 20,
 708                 (unsigned long)memblock.memory.total_size >> 20);
 709         os_info_crashkernel_add(crash_base, crash_size);
 710 #endif
 711 }
 712
 713 /*
 714  * Reserve the initrd from being used by memblock
 715  */
 716 static void __init reserve_initrd(void)
 717 {
 718 #ifdef CONFIG_BLK_DEV_INITRD
 719         if (!initrd_data.start || !initrd_data.size)
 720                 return;
 721         initrd_start = initrd_data.start;
 722         initrd_end = initrd_start + initrd_data.size;
 723         memblock_reserve(initrd_data.start, initrd_data.size);
 724 #endif
 725 }
 726
 727 /*
 728  * Reserve the memory area used to pass the certificate lists
 729  */
 730 static void __init reserve_certificate_list(void)
 731 {
 732         if (ipl_cert_list_addr)
 733                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 734 }
 735
 736 static void __init reserve_mem_detect_info(void)
 737 {
 738         unsigned long start, size;
 739
 740         get_mem_detect_reserved(&start, &size);
 741         if (size)
 742                 memblock_reserve(start, size);
 743 }
 744
 745 static void __init free_mem_detect_info(void)
 746 {
 747         unsigned long start, size;
 748
 749         get_mem_detect_reserved(&start, &size);
 750         if (size)
 751                 memblock_free(start, size);
 752 }
 753
 754 static const char * __init get_mem_info_source(void)
 755 {
 756         switch (mem_detect.info_source) {
 757         case MEM_DETECT_SCLP_STOR_INFO:
 758                 return "sclp storage info";
 759         case MEM_DETECT_DIAG260:
 760                 return "diag260";
 761         case MEM_DETECT_SCLP_READ_INFO:
 762                 return "sclp read info";
 763         case MEM_DETECT_BIN_SEARCH:
 764                 return "binary search";
 765         }
 766         return "none";
 767 }
 768
 769 static void __init memblock_add_mem_detect_info(void)
 770 {
 771         unsigned long start, end;
 772         int i;
 773
 774         pr_debug("physmem info source: %s (%hhd)\n",
 775                  get_mem_info_source(), mem_detect.info_source);
 776         /* keep memblock lists close to the kernel */
 777         memblock_set_bottom_up(true);
 778         for_each_mem_detect_block(i, &start, &end) {
 779                 memblock_add(start, end - start);
 780                 memblock_physmem_add(start, end - start);
 781         }
 782         memblock_set_bottom_up(false);
 783         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 784         memblock_dump_all();
 785 }
 786
 787 /*
 788  * Check for initrd being in usable memory
 789  */
 790 static void __init check_initrd(void)
 791 {
 792 #ifdef CONFIG_BLK_DEV_INITRD
 793         if (initrd_data.start && initrd_data.size &&
 794             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 795                 pr_err("The initial RAM disk does not fit into the memory\n");
 796                 memblock_free(initrd_data.start, initrd_data.size);
 797                 initrd_start = initrd_end = 0;
 798         }
 799 #endif
 800 }
 801
 802 /*
 803  * Reserve memory used for lowcore/command line/kernel image.
 804  */
 805 static void __init reserve_kernel(void)
 806 {
 807         unsigned long start_pfn = PFN_UP(__pa(_end));
 808
 809         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 810         memblock_reserve((unsigned long)sclp_early_sccb, EXT_SCCB_READ_SCP);
 811         memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
 812                          - (unsigned long)_stext);
 813 }
 814
 815 static void __init setup_memory(void)
 816 {
 817         phys_addr_t start, end;
 818         u64 i;
 819
 820         /*
 821          * Init storage key for present memory
 822          */
 823         for_each_mem_range(i, &start, &end)
 824                 storage_key_init_range(start, end);
 825
 826         psw_set_key(PAGE_DEFAULT_KEY);
 827
 828         /* Only cosmetics */
 829         memblock_enforce_memory_limit(memblock_end_of_DRAM());
 830 }
 831
 832 static void __init relocate_amode31_section(void)
 833 {
 834         unsigned long amode31_addr, amode31_size;
 835         long amode31_offset;
 836         long *ptr;
 837
 838         /* Allocate a new AMODE31 capable memory region */
 839         amode31_size = __eamode31 - __samode31;
 840         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 841         amode31_addr = (unsigned long)memblock_alloc_low(amode31_size, PAGE_SIZE);
 842         if (!amode31_addr)
 843                 panic("Failed to allocate memory for AMODE31 section\n");
 844         amode31_offset = amode31_addr - __samode31;
 845
 846         /* Move original AMODE31 section to the new one */
 847         memmove((void *)amode31_addr, (void *)__samode31, amode31_size);
 848         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 849         memset((void *)__samode31, 0, amode31_size);
 850
 851         /* Update all AMODE31 region references */
 852         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 853                 *ptr += amode31_offset;
 854 }
 855
 856 /* This must be called after AMODE31 relocation */
 857 static void __init setup_cr(void)
 858 {
 859         union ctlreg2 cr2;
 860         union ctlreg5 cr5;
 861         union ctlreg15 cr15;
 862
 863         __ctl_duct[1] = (unsigned long)__ctl_aste;
 864         __ctl_duct[2] = (unsigned long)__ctl_aste;
 865         __ctl_duct[4] = (unsigned long)__ctl_duald;
 866
 867         /* Update control registers CR2, CR5 and CR15 */
 868         __ctl_store(cr2.val, 2, 2);
 869         __ctl_store(cr5.val, 5, 5);
 870         __ctl_store(cr15.val, 15, 15);
 871         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 872         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 873         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 874         __ctl_load(cr2.val, 2, 2);
 875         __ctl_load(cr5.val, 5, 5);
 876         __ctl_load(cr15.val, 15, 15);
 877 }
 878
 879 /*
 880  * Add system information as device randomness
 881  */
 882 static void __init setup_randomness(void)
 883 {
 884         struct sysinfo_3_2_2 *vmms;
 885
 886         vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
 887                                                             PAGE_SIZE);
 888         if (!vmms)
 889                 panic("Failed to allocate memory for sysinfo structure\n");
 890
 891         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 892                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 893         memblock_free((unsigned long) vmms, PAGE_SIZE);
 894 }
 895
 896 /*
 897  * Find the correct size for the task_struct. This depends on
 898  * the size of the struct fpu at the end of the thread_struct
 899  * which is embedded in the task_struct.
 900  */
 901 static void __init setup_task_size(void)
 902 {
 903         int task_size = sizeof(struct task_struct);
 904
 905         if (!MACHINE_HAS_VX) {
 906                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 907                 task_size += sizeof(freg_t) * __NUM_FPRS;
 908         }
 909         arch_task_struct_size = task_size;
 910 }
 911
 912 /*
 913  * Issue diagnose 318 to set the control program name and
 914  * version codes.
 915  */
 916 static void __init setup_control_program_code(void)
 917 {
 918         union diag318_info diag318_info = {
 919                 .cpnc = CPNC_LINUX,
 920                 .cpvc = 0,
 921         };
 922
 923         if (!sclp.has_diag318)
 924                 return;
 925
 926         diag_stat_inc(DIAG_STAT_X318);
 927         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 928 }
 929
 930 /*
 931  * Print the component list from the IPL report
 932  */
 933 static void __init log_component_list(void)
 934 {
 935         struct ipl_rb_component_entry *ptr, *end;
 936         char *str;
 937
 938         if (!early_ipl_comp_list_addr)
 939                 return;
 940         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 941                 pr_info("Linux is running with Secure-IPL enabled\n");
 942         else
 943                 pr_info("Linux is running with Secure-IPL disabled\n");
 944         ptr = (void *) early_ipl_comp_list_addr;
 945         end = (void *) ptr + early_ipl_comp_list_size;
 946         pr_info("The IPL report contains the following components:\n");
 947         while (ptr < end) {
 948                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 949                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 950                                 str = "signed, verified";
 951                         else
 952                                 str = "signed, verification failed";
 953                 } else {
 954                         str = "not signed";
 955                 }
 956                 pr_info("%016llx - %016llx (%s)\n",
 957                         ptr->addr, ptr->addr + ptr->len, str);
 958                 ptr++;
 959         }
 960 }
 961
 962 /*
 963  * Setup function called from init/main.c just after the banner
 964  * was printed.
 965  */
 966
 967 void __init setup_arch(char **cmdline_p)
 968 {
 969         /*
 970          * print what head.S has found out about the machine
 971          */
 972         if (MACHINE_IS_VM)
 973                 pr_info("Linux is running as a z/VM "
 974                         "guest operating system in 64-bit mode\n");
 975         else if (MACHINE_IS_KVM)
 976                 pr_info("Linux is running under KVM in 64-bit mode\n");
 977         else if (MACHINE_IS_LPAR)
 978                 pr_info("Linux is running natively in 64-bit mode\n");
 979         else
 980                 pr_info("Linux is running as a guest in 64-bit mode\n");
 981
 982         log_component_list();
 983
 984         /* Have one command line that is parsed and saved in /proc/cmdline */
 985         /* boot_command_line has been already set up in early.c */
 986         *cmdline_p = boot_command_line;
 987
 988         ROOT_DEV = Root_RAM0;
 989
 990         setup_initial_init_mm(_text, _etext, _edata, _end);
 991
 992         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 993                 nospec_auto_detect();
 994
 995         jump_label_init();
 996         parse_early_param();
 997 #ifdef CONFIG_CRASH_DUMP
 998         /* Deactivate elfcorehdr= kernel parameter */
 999         elfcorehdr_addr = ELFCORE_ADDR_MAX;
1000 #endif
1001
1002         os_info_init();
1003         setup_ipl();
1004         setup_task_size();
1005         setup_control_program_code();
1006
1007         /* Do some memory reservations *before* memory is added to memblock */
1008         reserve_above_ident_map();
1009         reserve_kernel();
1010         reserve_initrd();
1011         reserve_certificate_list();
1012         reserve_mem_detect_info();
1013         memblock_allow_resize();
1014
1015         /* Get information about *all* installed memory */
1016         memblock_add_mem_detect_info();
1017
1018         free_mem_detect_info();
1019
1020         relocate_amode31_section();
1021         setup_cr();
1022
1023         setup_uv();
1024         setup_memory_end();
1025         setup_memory();
1026         dma_contiguous_reserve(ident_map_size);
1027         vmcp_cma_reserve();
1028         if (MACHINE_HAS_EDAT2)
1029                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1030
1031         check_initrd();
1032         reserve_crashkernel();
1033 #ifdef CONFIG_CRASH_DUMP
1034         /*
1035          * Be aware that smp_save_dump_cpus() triggers a system reset.
1036          * Therefore CPU and device initialization should be done afterwards.
1037          */
1038         smp_save_dump_cpus();
1039 #endif
1040
1041         setup_resources();
1042         setup_lowcore_dat_off();
1043         smp_fill_possible_mask();
1044         cpu_detect_mhz_feature();
1045         cpu_init();
1046         numa_setup();
1047         smp_detect_cpus();
1048         topology_init_early();
1049
1050         /*
1051          * Create kernel page tables and switch to virtual addressing.
1052          */
1053         paging_init();
1054
1055         /*
1056          * After paging_init created the kernel page table, the new PSWs
1057          * in lowcore can now run with DAT enabled.
1058          */
1059         setup_lowcore_dat_on();
1060
1061         /* Setup default console */
1062         conmode_default();
1063         set_preferred_console();
1064
1065         apply_alternative_instructions();
1066         if (IS_ENABLED(CONFIG_EXPOLINE))
1067                 nospec_init_branches();
1068
1069         /* Setup zfcp/nvme dump support */
1070         setup_zfcpdump();
1071
1072         /* Add system specific data to the random pool */
1073         setup_randomness();
1074 }