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 = (unsigned long)&_samode31;
  99 unsigned long __amode31_ref __eamode31 = (unsigned long)&_eamode31;
 100 unsigned long __amode31_ref __stext_amode31 = (unsigned long)&_stext_amode31;
 101 unsigned long __amode31_ref __etext_amode31 = (unsigned long)&_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 long __bootdata(__amode31_base);
 153 unsigned int __bootdata_preserved(zlib_dfltcc_support);
 154 EXPORT_SYMBOL(zlib_dfltcc_support);
 155 u64 __bootdata_preserved(stfle_fac_list[16]);
 156 EXPORT_SYMBOL(stfle_fac_list);
 157 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 158 struct oldmem_data __bootdata_preserved(oldmem_data);
 159
 160 unsigned long VMALLOC_START;
 161 EXPORT_SYMBOL(VMALLOC_START);
 162
 163 unsigned long VMALLOC_END;
 164 EXPORT_SYMBOL(VMALLOC_END);
 165
 166 struct page *vmemmap;
 167 EXPORT_SYMBOL(vmemmap);
 168 unsigned long vmemmap_size;
 169
 170 unsigned long MODULES_VADDR;
 171 unsigned long MODULES_END;
 172
 173 /* An array with a pointer to the lowcore of every CPU. */
 174 struct lowcore *lowcore_ptr[NR_CPUS];
 175 EXPORT_SYMBOL(lowcore_ptr);
 176
 177 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
 178
 179 /*
 180  * The Write Back bit position in the physaddr is given by the SLPC PCI.
 181  * Leaving the mask zero always uses write through which is safe
 182  */
 183 unsigned long mio_wb_bit_mask __ro_after_init;
 184
 185 /*
 186  * This is set up by the setup-routine at boot-time
 187  * for S390 need to find out, what we have to setup
 188  * using address 0x10400 ...
 189  */
 190
 191 #include <asm/setup.h>
 192
 193 /*
 194  * condev= and conmode= setup parameter.
 195  */
 196
 197 static int __init condev_setup(char *str)
 198 {
 199         int vdev;
 200
 201         vdev = simple_strtoul(str, &str, 0);
 202         if (vdev >= 0 && vdev < 65536) {
 203                 console_devno = vdev;
 204                 console_irq = -1;
 205         }
 206         return 1;
 207 }
 208
 209 __setup("condev=", condev_setup);
 210
 211 static void __init set_preferred_console(void)
 212 {
 213         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 214                 add_preferred_console("ttyS", 0, NULL);
 215         else if (CONSOLE_IS_3270)
 216                 add_preferred_console("tty3270", 0, NULL);
 217         else if (CONSOLE_IS_VT220)
 218                 add_preferred_console("ttysclp", 0, NULL);
 219         else if (CONSOLE_IS_HVC)
 220                 add_preferred_console("hvc", 0, NULL);
 221 }
 222
 223 static int __init conmode_setup(char *str)
 224 {
 225 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 226         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 227                 SET_CONSOLE_SCLP;
 228 #endif
 229 #if defined(CONFIG_TN3215_CONSOLE)
 230         if (!strcmp(str, "3215"))
 231                 SET_CONSOLE_3215;
 232 #endif
 233 #if defined(CONFIG_TN3270_CONSOLE)
 234         if (!strcmp(str, "3270"))
 235                 SET_CONSOLE_3270;
 236 #endif
 237         set_preferred_console();
 238         return 1;
 239 }
 240
 241 __setup("conmode=", conmode_setup);
 242
 243 static void __init conmode_default(void)
 244 {
 245         char query_buffer[1024];
 246         char *ptr;
 247
 248         if (MACHINE_IS_VM) {
 249                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 250                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 251                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 252                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 253                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 254                 ptr = strstr(query_buffer, "CONMODE");
 255                 /*
 256                  * Set the conmode to 3215 so that the device recognition
 257                  * will set the cu_type of the console to 3215. If the
 258                  * conmode is 3270 and we don't set it back then both
 259                  * 3215 and the 3270 driver will try to access the console
 260                  * device (3215 as console and 3270 as normal tty).
 261                  */
 262                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 263                 if (ptr == NULL) {
 264 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 265                         SET_CONSOLE_SCLP;
 266 #endif
 267                         return;
 268                 }
 269                 if (str_has_prefix(ptr + 8, "3270")) {
 270 #if defined(CONFIG_TN3270_CONSOLE)
 271                         SET_CONSOLE_3270;
 272 #elif defined(CONFIG_TN3215_CONSOLE)
 273                         SET_CONSOLE_3215;
 274 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 275                         SET_CONSOLE_SCLP;
 276 #endif
 277                 } else if (str_has_prefix(ptr + 8, "3215")) {
 278 #if defined(CONFIG_TN3215_CONSOLE)
 279                         SET_CONSOLE_3215;
 280 #elif defined(CONFIG_TN3270_CONSOLE)
 281                         SET_CONSOLE_3270;
 282 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 283                         SET_CONSOLE_SCLP;
 284 #endif
 285                 }
 286         } else if (MACHINE_IS_KVM) {
 287                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 288                         SET_CONSOLE_VT220;
 289                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 290                         SET_CONSOLE_SCLP;
 291                 else
 292                         SET_CONSOLE_HVC;
 293         } else {
 294 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 295                 SET_CONSOLE_SCLP;
 296 #endif
 297         }
 298 }
 299
 300 #ifdef CONFIG_CRASH_DUMP
 301 static void __init setup_zfcpdump(void)
 302 {
 303         if (!is_ipl_type_dump())
 304                 return;
 305         if (oldmem_data.start)
 306                 return;
 307         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 308         console_loglevel = 2;
 309 }
 310 #else
 311 static inline void setup_zfcpdump(void) {}
 312 #endif /* CONFIG_CRASH_DUMP */
 313
 314  /*
 315  * Reboot, halt and power_off stubs. They just call _machine_restart,
 316  * _machine_halt or _machine_power_off.
 317  */
 318
 319 void machine_restart(char *command)
 320 {
 321         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 322                 /*
 323                  * Only unblank the console if we are called in enabled
 324                  * context or a bust_spinlocks cleared the way for us.
 325                  */
 326                 console_unblank();
 327         _machine_restart(command);
 328 }
 329
 330 void machine_halt(void)
 331 {
 332         if (!in_interrupt() || oops_in_progress)
 333                 /*
 334                  * Only unblank the console if we are called in enabled
 335                  * context or a bust_spinlocks cleared the way for us.
 336                  */
 337                 console_unblank();
 338         _machine_halt();
 339 }
 340
 341 void machine_power_off(void)
 342 {
 343         if (!in_interrupt() || oops_in_progress)
 344                 /*
 345                  * Only unblank the console if we are called in enabled
 346                  * context or a bust_spinlocks cleared the way for us.
 347                  */
 348                 console_unblank();
 349         _machine_power_off();
 350 }
 351
 352 /*
 353  * Dummy power off function.
 354  */
 355 void (*pm_power_off)(void) = machine_power_off;
 356 EXPORT_SYMBOL_GPL(pm_power_off);
 357
 358 void *restart_stack;
 359
 360 unsigned long stack_alloc(void)
 361 {
 362 #ifdef CONFIG_VMAP_STACK
 363         void *ret;
 364
 365         ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
 366                              NUMA_NO_NODE, __builtin_return_address(0));
 367         kmemleak_not_leak(ret);
 368         return (unsigned long)ret;
 369 #else
 370         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 371 #endif
 372 }
 373
 374 void stack_free(unsigned long stack)
 375 {
 376 #ifdef CONFIG_VMAP_STACK
 377         vfree((void *) stack);
 378 #else
 379         free_pages(stack, THREAD_SIZE_ORDER);
 380 #endif
 381 }
 382
 383 int __init arch_early_irq_init(void)
 384 {
 385         unsigned long stack;
 386
 387         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 388         if (!stack)
 389                 panic("Couldn't allocate async stack");
 390         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 391         return 0;
 392 }
 393
 394 void __init arch_call_rest_init(void)
 395 {
 396         unsigned long stack;
 397
 398         stack = stack_alloc();
 399         if (!stack)
 400                 panic("Couldn't allocate kernel stack");
 401         current->stack = (void *) stack;
 402 #ifdef CONFIG_VMAP_STACK
 403         current->stack_vm_area = (void *) stack;
 404 #endif
 405         set_task_stack_end_magic(current);
 406         stack += STACK_INIT_OFFSET;
 407         S390_lowcore.kernel_stack = stack;
 408         call_on_stack_noreturn(rest_init, stack);
 409 }
 410
 411 static void __init setup_lowcore_dat_off(void)
 412 {
 413         unsigned long int_psw_mask = PSW_KERNEL_BITS;
 414         unsigned long mcck_stack;
 415         struct lowcore *lc;
 416
 417         if (IS_ENABLED(CONFIG_KASAN))
 418                 int_psw_mask |= PSW_MASK_DAT;
 419
 420         /*
 421          * Setup lowcore for boot cpu
 422          */
 423         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 424         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 425         if (!lc)
 426                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 427                       __func__, sizeof(*lc), sizeof(*lc));
 428
 429         lc->restart_psw.mask = PSW_KERNEL_BITS;
 430         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 431         lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 432         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 433         lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 434         lc->svc_new_psw.addr = (unsigned long) system_call;
 435         lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 436         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 437         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 438         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 439         lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 440         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 441         lc->clock_comparator = clock_comparator_max;
 442         lc->nodat_stack = ((unsigned long) &init_thread_union)
 443                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 444         lc->current_task = (unsigned long)&init_task;
 445         lc->lpp = LPP_MAGIC;
 446         lc->machine_flags = S390_lowcore.machine_flags;
 447         lc->preempt_count = S390_lowcore.preempt_count;
 448         nmi_alloc_mcesa_early(&lc->mcesad);
 449         lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 450         lc->exit_timer = S390_lowcore.exit_timer;
 451         lc->user_timer = S390_lowcore.user_timer;
 452         lc->system_timer = S390_lowcore.system_timer;
 453         lc->steal_timer = S390_lowcore.steal_timer;
 454         lc->last_update_timer = S390_lowcore.last_update_timer;
 455         lc->last_update_clock = S390_lowcore.last_update_clock;
 456
 457         /*
 458          * Allocate the global restart stack which is the same for
 459          * all CPUs in cast *one* of them does a PSW restart.
 460          */
 461         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 462         if (!restart_stack)
 463                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 464                       __func__, THREAD_SIZE, THREAD_SIZE);
 465         restart_stack += STACK_INIT_OFFSET;
 466
 467         /*
 468          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 469          * restart data to the absolute zero lowcore. This is necessary if
 470          * PSW restart is done on an offline CPU that has lowcore zero.
 471          */
 472         lc->restart_stack = (unsigned long) restart_stack;
 473         lc->restart_fn = (unsigned long) do_restart;
 474         lc->restart_data = 0;
 475         lc->restart_source = -1U;
 476
 477         mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 478         if (!mcck_stack)
 479                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 480                       __func__, THREAD_SIZE, THREAD_SIZE);
 481         lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 482
 483         /* Setup absolute zero lowcore */
 484         mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
 485         mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
 486         mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
 487         mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
 488         mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 489
 490         lc->spinlock_lockval = arch_spin_lockval(0);
 491         lc->spinlock_index = 0;
 492         arch_spin_lock_setup(0);
 493         lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 494         lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 495         lc->preempt_count = PREEMPT_DISABLED;
 496
 497         set_prefix((u32)(unsigned long) lc);
 498         lowcore_ptr[0] = lc;
 499 }
 500
 501 static void __init setup_lowcore_dat_on(void)
 502 {
 503         struct lowcore *lc = lowcore_ptr[0];
 504
 505         __ctl_clear_bit(0, 28);
 506         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 507         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 508         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 509         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 510         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 511         __ctl_set_bit(0, 28);
 512         mem_assign_absolute(S390_lowcore.restart_flags, RESTART_FLAG_CTLREGS);
 513         mem_assign_absolute(S390_lowcore.program_new_psw, lc->program_new_psw);
 514         memcpy_absolute(&S390_lowcore.cregs_save_area, lc->cregs_save_area,
 515                         sizeof(S390_lowcore.cregs_save_area));
 516 }
 517
 518 static struct resource code_resource = {
 519         .name  = "Kernel code",
 520         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 521 };
 522
 523 static struct resource data_resource = {
 524         .name = "Kernel data",
 525         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 526 };
 527
 528 static struct resource bss_resource = {
 529         .name = "Kernel bss",
 530         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 531 };
 532
 533 static struct resource __initdata *standard_resources[] = {
 534         &code_resource,
 535         &data_resource,
 536         &bss_resource,
 537 };
 538
 539 static void __init setup_resources(void)
 540 {
 541         struct resource *res, *std_res, *sub_res;
 542         phys_addr_t start, end;
 543         int j;
 544         u64 i;
 545
 546         code_resource.start = (unsigned long) _text;
 547         code_resource.end = (unsigned long) _etext - 1;
 548         data_resource.start = (unsigned long) _etext;
 549         data_resource.end = (unsigned long) _edata - 1;
 550         bss_resource.start = (unsigned long) __bss_start;
 551         bss_resource.end = (unsigned long) __bss_stop - 1;
 552
 553         for_each_mem_range(i, &start, &end) {
 554                 res = memblock_alloc(sizeof(*res), 8);
 555                 if (!res)
 556                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 557                               __func__, sizeof(*res), 8);
 558                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 559
 560                 res->name = "System RAM";
 561                 res->start = start;
 562                 /*
 563                  * In memblock, end points to the first byte after the
 564                  * range while in resourses, end points to the last byte in
 565                  * the range.
 566                  */
 567                 res->end = end - 1;
 568                 request_resource(&iomem_resource, res);
 569
 570                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 571                         std_res = standard_resources[j];
 572                         if (std_res->start < res->start ||
 573                             std_res->start > res->end)
 574                                 continue;
 575                         if (std_res->end > res->end) {
 576                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 577                                 if (!sub_res)
 578                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 579                                               __func__, sizeof(*sub_res), 8);
 580                                 *sub_res = *std_res;
 581                                 sub_res->end = res->end;
 582                                 std_res->start = res->end + 1;
 583                                 request_resource(res, sub_res);
 584                         } else {
 585                                 request_resource(res, std_res);
 586                         }
 587                 }
 588         }
 589 #ifdef CONFIG_CRASH_DUMP
 590         /*
 591          * Re-add removed crash kernel memory as reserved memory. This makes
 592          * sure it will be mapped with the identity mapping and struct pages
 593          * will be created, so it can be resized later on.
 594          * However add it later since the crash kernel resource should not be
 595          * part of the System RAM resource.
 596          */
 597         if (crashk_res.end) {
 598                 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 599                                   0, MEMBLOCK_NONE);
 600                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 601                 insert_resource(&iomem_resource, &crashk_res);
 602         }
 603 #endif
 604 }
 605
 606 static void __init setup_memory_end(void)
 607 {
 608         memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 609         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 610         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 611 }
 612
 613 #ifdef CONFIG_CRASH_DUMP
 614
 615 /*
 616  * When kdump is enabled, we have to ensure that no memory from the area
 617  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 618  * the crashkernel memory region when kdump is triggered. The crashkernel
 619  * memory region can never get offlined (pages are unmovable).
 620  */
 621 static int kdump_mem_notifier(struct notifier_block *nb,
 622                               unsigned long action, void *data)
 623 {
 624         struct memory_notify *arg = data;
 625
 626         if (action != MEM_GOING_OFFLINE)
 627                 return NOTIFY_OK;
 628         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 629                 return NOTIFY_BAD;
 630         return NOTIFY_OK;
 631 }
 632
 633 static struct notifier_block kdump_mem_nb = {
 634         .notifier_call = kdump_mem_notifier,
 635 };
 636
 637 #endif
 638
 639 /*
 640  * Reserve memory for kdump kernel to be loaded with kexec
 641  */
 642 static void __init reserve_crashkernel(void)
 643 {
 644 #ifdef CONFIG_CRASH_DUMP
 645         unsigned long long crash_base, crash_size;
 646         phys_addr_t low, high;
 647         int rc;
 648
 649         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 650                                &crash_base);
 651
 652         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 653         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 654         if (rc || crash_size == 0)
 655                 return;
 656
 657         if (memblock.memory.regions[0].size < crash_size) {
 658                 pr_info("crashkernel reservation failed: %s\n",
 659                         "first memory chunk must be at least crashkernel size");
 660                 return;
 661         }
 662
 663         low = crash_base ?: oldmem_data.start;
 664         high = low + crash_size;
 665         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 666                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 667                 crash_base = low;
 668         } else {
 669                 /* Find suitable area in free memory */
 670                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 671                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 672
 673                 if (crash_base && crash_base < low) {
 674                         pr_info("crashkernel reservation failed: %s\n",
 675                                 "crash_base too low");
 676                         return;
 677                 }
 678                 low = crash_base ?: low;
 679                 crash_base = memblock_phys_alloc_range(crash_size,
 680                                                        KEXEC_CRASH_MEM_ALIGN,
 681                                                        low, high);
 682         }
 683
 684         if (!crash_base) {
 685                 pr_info("crashkernel reservation failed: %s\n",
 686                         "no suitable area found");
 687                 return;
 688         }
 689
 690         if (register_memory_notifier(&kdump_mem_nb)) {
 691                 memblock_phys_free(crash_base, crash_size);
 692                 return;
 693         }
 694
 695         if (!oldmem_data.start && MACHINE_IS_VM)
 696                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 697         crashk_res.start = crash_base;
 698         crashk_res.end = crash_base + crash_size - 1;
 699         memblock_remove(crash_base, crash_size);
 700         pr_info("Reserving %lluMB of memory at %lluMB "
 701                 "for crashkernel (System RAM: %luMB)\n",
 702                 crash_size >> 20, crash_base >> 20,
 703                 (unsigned long)memblock.memory.total_size >> 20);
 704         os_info_crashkernel_add(crash_base, crash_size);
 705 #endif
 706 }
 707
 708 /*
 709  * Reserve the initrd from being used by memblock
 710  */
 711 static void __init reserve_initrd(void)
 712 {
 713 #ifdef CONFIG_BLK_DEV_INITRD
 714         if (!initrd_data.start || !initrd_data.size)
 715                 return;
 716         initrd_start = (unsigned long)__va(initrd_data.start);
 717         initrd_end = initrd_start + initrd_data.size;
 718         memblock_reserve(initrd_data.start, initrd_data.size);
 719 #endif
 720 }
 721
 722 /*
 723  * Reserve the memory area used to pass the certificate lists
 724  */
 725 static void __init reserve_certificate_list(void)
 726 {
 727         if (ipl_cert_list_addr)
 728                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 729 }
 730
 731 static void __init reserve_mem_detect_info(void)
 732 {
 733         unsigned long start, size;
 734
 735         get_mem_detect_reserved(&start, &size);
 736         if (size)
 737                 memblock_reserve(start, size);
 738 }
 739
 740 static void __init free_mem_detect_info(void)
 741 {
 742         unsigned long start, size;
 743
 744         get_mem_detect_reserved(&start, &size);
 745         if (size)
 746                 memblock_phys_free(start, size);
 747 }
 748
 749 static const char * __init get_mem_info_source(void)
 750 {
 751         switch (mem_detect.info_source) {
 752         case MEM_DETECT_SCLP_STOR_INFO:
 753                 return "sclp storage info";
 754         case MEM_DETECT_DIAG260:
 755                 return "diag260";
 756         case MEM_DETECT_SCLP_READ_INFO:
 757                 return "sclp read info";
 758         case MEM_DETECT_BIN_SEARCH:
 759                 return "binary search";
 760         }
 761         return "none";
 762 }
 763
 764 static void __init memblock_add_mem_detect_info(void)
 765 {
 766         unsigned long start, end;
 767         int i;
 768
 769         pr_debug("physmem info source: %s (%hhd)\n",
 770                  get_mem_info_source(), mem_detect.info_source);
 771         /* keep memblock lists close to the kernel */
 772         memblock_set_bottom_up(true);
 773         for_each_mem_detect_block(i, &start, &end) {
 774                 memblock_add(start, end - start);
 775                 memblock_physmem_add(start, end - start);
 776         }
 777         memblock_set_bottom_up(false);
 778         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 779 }
 780
 781 /*
 782  * Check for initrd being in usable memory
 783  */
 784 static void __init check_initrd(void)
 785 {
 786 #ifdef CONFIG_BLK_DEV_INITRD
 787         if (initrd_data.start && initrd_data.size &&
 788             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 789                 pr_err("The initial RAM disk does not fit into the memory\n");
 790                 memblock_phys_free(initrd_data.start, initrd_data.size);
 791                 initrd_start = initrd_end = 0;
 792         }
 793 #endif
 794 }
 795
 796 /*
 797  * Reserve memory used for lowcore/command line/kernel image.
 798  */
 799 static void __init reserve_kernel(void)
 800 {
 801         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 802         memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 803         memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 804         memblock_reserve(__amode31_base, __eamode31 - __samode31);
 805         memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 806         memblock_reserve(__pa(_stext), _end - _stext);
 807 }
 808
 809 static void __init setup_memory(void)
 810 {
 811         phys_addr_t start, end;
 812         u64 i;
 813
 814         /*
 815          * Init storage key for present memory
 816          */
 817         for_each_mem_range(i, &start, &end)
 818                 storage_key_init_range(start, end);
 819
 820         psw_set_key(PAGE_DEFAULT_KEY);
 821 }
 822
 823 static void __init relocate_amode31_section(void)
 824 {
 825         unsigned long amode31_size = __eamode31 - __samode31;
 826         long amode31_offset = __amode31_base - __samode31;
 827         long *ptr;
 828
 829         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 830
 831         /* Move original AMODE31 section to the new one */
 832         memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 833         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 834         memset((void *)__samode31, 0, amode31_size);
 835
 836         /* Update all AMODE31 region references */
 837         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 838                 *ptr += amode31_offset;
 839 }
 840
 841 /* This must be called after AMODE31 relocation */
 842 static void __init setup_cr(void)
 843 {
 844         union ctlreg2 cr2;
 845         union ctlreg5 cr5;
 846         union ctlreg15 cr15;
 847
 848         __ctl_duct[1] = (unsigned long)__ctl_aste;
 849         __ctl_duct[2] = (unsigned long)__ctl_aste;
 850         __ctl_duct[4] = (unsigned long)__ctl_duald;
 851
 852         /* Update control registers CR2, CR5 and CR15 */
 853         __ctl_store(cr2.val, 2, 2);
 854         __ctl_store(cr5.val, 5, 5);
 855         __ctl_store(cr15.val, 15, 15);
 856         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 857         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 858         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 859         __ctl_load(cr2.val, 2, 2);
 860         __ctl_load(cr5.val, 5, 5);
 861         __ctl_load(cr15.val, 15, 15);
 862 }
 863
 864 /*
 865  * Add system information as device randomness
 866  */
 867 static void __init setup_randomness(void)
 868 {
 869         struct sysinfo_3_2_2 *vmms;
 870
 871         vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 872         if (!vmms)
 873                 panic("Failed to allocate memory for sysinfo structure\n");
 874         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 875                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 876         memblock_free(vmms, PAGE_SIZE);
 877 }
 878
 879 /*
 880  * Find the correct size for the task_struct. This depends on
 881  * the size of the struct fpu at the end of the thread_struct
 882  * which is embedded in the task_struct.
 883  */
 884 static void __init setup_task_size(void)
 885 {
 886         int task_size = sizeof(struct task_struct);
 887
 888         if (!MACHINE_HAS_VX) {
 889                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 890                 task_size += sizeof(freg_t) * __NUM_FPRS;
 891         }
 892         arch_task_struct_size = task_size;
 893 }
 894
 895 /*
 896  * Issue diagnose 318 to set the control program name and
 897  * version codes.
 898  */
 899 static void __init setup_control_program_code(void)
 900 {
 901         union diag318_info diag318_info = {
 902                 .cpnc = CPNC_LINUX,
 903                 .cpvc = 0,
 904         };
 905
 906         if (!sclp.has_diag318)
 907                 return;
 908
 909         diag_stat_inc(DIAG_STAT_X318);
 910         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 911 }
 912
 913 /*
 914  * Print the component list from the IPL report
 915  */
 916 static void __init log_component_list(void)
 917 {
 918         struct ipl_rb_component_entry *ptr, *end;
 919         char *str;
 920
 921         if (!early_ipl_comp_list_addr)
 922                 return;
 923         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 924                 pr_info("Linux is running with Secure-IPL enabled\n");
 925         else
 926                 pr_info("Linux is running with Secure-IPL disabled\n");
 927         ptr = (void *) early_ipl_comp_list_addr;
 928         end = (void *) ptr + early_ipl_comp_list_size;
 929         pr_info("The IPL report contains the following components:\n");
 930         while (ptr < end) {
 931                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 932                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 933                                 str = "signed, verified";
 934                         else
 935                                 str = "signed, verification failed";
 936                 } else {
 937                         str = "not signed";
 938                 }
 939                 pr_info("%016llx - %016llx (%s)\n",
 940                         ptr->addr, ptr->addr + ptr->len, str);
 941                 ptr++;
 942         }
 943 }
 944
 945 /*
 946  * Setup function called from init/main.c just after the banner
 947  * was printed.
 948  */
 949
 950 void __init setup_arch(char **cmdline_p)
 951 {
 952         /*
 953          * print what head.S has found out about the machine
 954          */
 955         if (MACHINE_IS_VM)
 956                 pr_info("Linux is running as a z/VM "
 957                         "guest operating system in 64-bit mode\n");
 958         else if (MACHINE_IS_KVM)
 959                 pr_info("Linux is running under KVM in 64-bit mode\n");
 960         else if (MACHINE_IS_LPAR)
 961                 pr_info("Linux is running natively in 64-bit mode\n");
 962         else
 963                 pr_info("Linux is running as a guest in 64-bit mode\n");
 964
 965         log_component_list();
 966
 967         /* Have one command line that is parsed and saved in /proc/cmdline */
 968         /* boot_command_line has been already set up in early.c */
 969         *cmdline_p = boot_command_line;
 970
 971         ROOT_DEV = Root_RAM0;
 972
 973         setup_initial_init_mm(_text, _etext, _edata, _end);
 974
 975         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 976                 nospec_auto_detect();
 977
 978         jump_label_init();
 979         parse_early_param();
 980 #ifdef CONFIG_CRASH_DUMP
 981         /* Deactivate elfcorehdr= kernel parameter */
 982         elfcorehdr_addr = ELFCORE_ADDR_MAX;
 983 #endif
 984
 985         os_info_init();
 986         setup_ipl();
 987         setup_task_size();
 988         setup_control_program_code();
 989
 990         /* Do some memory reservations *before* memory is added to memblock */
 991         reserve_kernel();
 992         reserve_initrd();
 993         reserve_certificate_list();
 994         reserve_mem_detect_info();
 995         memblock_set_current_limit(ident_map_size);
 996         memblock_allow_resize();
 997
 998         /* Get information about *all* installed memory */
 999         memblock_add_mem_detect_info();
1000
1001         free_mem_detect_info();
1002         setup_memory_end();
1003         memblock_dump_all();
1004         setup_memory();
1005
1006         relocate_amode31_section();
1007         setup_cr();
1008         setup_uv();
1009         dma_contiguous_reserve(ident_map_size);
1010         vmcp_cma_reserve();
1011         if (MACHINE_HAS_EDAT2)
1012                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1013
1014         check_initrd();
1015         reserve_crashkernel();
1016 #ifdef CONFIG_CRASH_DUMP
1017         /*
1018          * Be aware that smp_save_dump_cpus() triggers a system reset.
1019          * Therefore CPU and device initialization should be done afterwards.
1020          */
1021         smp_save_dump_cpus();
1022 #endif
1023
1024         setup_resources();
1025         setup_lowcore_dat_off();
1026         smp_fill_possible_mask();
1027         cpu_detect_mhz_feature();
1028         cpu_init();
1029         numa_setup();
1030         smp_detect_cpus();
1031         topology_init_early();
1032
1033         if (test_facility(193))
1034                 static_branch_enable(&cpu_has_bear);
1035
1036         /*
1037          * Create kernel page tables and switch to virtual addressing.
1038          */
1039         paging_init();
1040
1041         /*
1042          * After paging_init created the kernel page table, the new PSWs
1043          * in lowcore can now run with DAT enabled.
1044          */
1045         setup_lowcore_dat_on();
1046
1047         /* Setup default console */
1048         conmode_default();
1049         set_preferred_console();
1050
1051         apply_alternative_instructions();
1052         if (IS_ENABLED(CONFIG_EXPOLINE))
1053                 nospec_init_branches();
1054
1055         /* Setup zfcp/nvme dump support */
1056         setup_zfcpdump();
1057
1058         /* Add system specific data to the random pool */
1059         setup_randomness();
1060 }