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         put_abs_lowcore(restart_stack, lc->restart_stack);
 485         put_abs_lowcore(restart_fn, lc->restart_fn);
 486         put_abs_lowcore(restart_data, lc->restart_data);
 487         put_abs_lowcore(restart_source, lc->restart_source);
 488         put_abs_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         int cr;
 505
 506         __ctl_clear_bit(0, 28);
 507         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 508         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 509         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 510         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 511         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 512         __ctl_set_bit(0, 28);
 513         put_abs_lowcore(restart_flags, RESTART_FLAG_CTLREGS);
 514         put_abs_lowcore(program_new_psw, lc->program_new_psw);
 515         for (cr = 0; cr < ARRAY_SIZE(lc->cregs_save_area); cr++)
 516                 put_abs_lowcore(cregs_save_area[cr], lc->cregs_save_area[cr]);
 517 }
 518
 519 static struct resource code_resource = {
 520         .name  = "Kernel code",
 521         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 522 };
 523
 524 static struct resource data_resource = {
 525         .name = "Kernel data",
 526         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 527 };
 528
 529 static struct resource bss_resource = {
 530         .name = "Kernel bss",
 531         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 532 };
 533
 534 static struct resource __initdata *standard_resources[] = {
 535         &code_resource,
 536         &data_resource,
 537         &bss_resource,
 538 };
 539
 540 static void __init setup_resources(void)
 541 {
 542         struct resource *res, *std_res, *sub_res;
 543         phys_addr_t start, end;
 544         int j;
 545         u64 i;
 546
 547         code_resource.start = (unsigned long) _text;
 548         code_resource.end = (unsigned long) _etext - 1;
 549         data_resource.start = (unsigned long) _etext;
 550         data_resource.end = (unsigned long) _edata - 1;
 551         bss_resource.start = (unsigned long) __bss_start;
 552         bss_resource.end = (unsigned long) __bss_stop - 1;
 553
 554         for_each_mem_range(i, &start, &end) {
 555                 res = memblock_alloc(sizeof(*res), 8);
 556                 if (!res)
 557                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 558                               __func__, sizeof(*res), 8);
 559                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 560
 561                 res->name = "System RAM";
 562                 res->start = start;
 563                 /*
 564                  * In memblock, end points to the first byte after the
 565                  * range while in resourses, end points to the last byte in
 566                  * the range.
 567                  */
 568                 res->end = end - 1;
 569                 request_resource(&iomem_resource, res);
 570
 571                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 572                         std_res = standard_resources[j];
 573                         if (std_res->start < res->start ||
 574                             std_res->start > res->end)
 575                                 continue;
 576                         if (std_res->end > res->end) {
 577                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 578                                 if (!sub_res)
 579                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 580                                               __func__, sizeof(*sub_res), 8);
 581                                 *sub_res = *std_res;
 582                                 sub_res->end = res->end;
 583                                 std_res->start = res->end + 1;
 584                                 request_resource(res, sub_res);
 585                         } else {
 586                                 request_resource(res, std_res);
 587                         }
 588                 }
 589         }
 590 #ifdef CONFIG_CRASH_DUMP
 591         /*
 592          * Re-add removed crash kernel memory as reserved memory. This makes
 593          * sure it will be mapped with the identity mapping and struct pages
 594          * will be created, so it can be resized later on.
 595          * However add it later since the crash kernel resource should not be
 596          * part of the System RAM resource.
 597          */
 598         if (crashk_res.end) {
 599                 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 600                                   0, MEMBLOCK_NONE);
 601                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 602                 insert_resource(&iomem_resource, &crashk_res);
 603         }
 604 #endif
 605 }
 606
 607 static void __init setup_memory_end(void)
 608 {
 609         memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 610         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 611         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 612 }
 613
 614 #ifdef CONFIG_CRASH_DUMP
 615
 616 /*
 617  * When kdump is enabled, we have to ensure that no memory from the area
 618  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 619  * the crashkernel memory region when kdump is triggered. The crashkernel
 620  * memory region can never get offlined (pages are unmovable).
 621  */
 622 static int kdump_mem_notifier(struct notifier_block *nb,
 623                               unsigned long action, void *data)
 624 {
 625         struct memory_notify *arg = data;
 626
 627         if (action != MEM_GOING_OFFLINE)
 628                 return NOTIFY_OK;
 629         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 630                 return NOTIFY_BAD;
 631         return NOTIFY_OK;
 632 }
 633
 634 static struct notifier_block kdump_mem_nb = {
 635         .notifier_call = kdump_mem_notifier,
 636 };
 637
 638 #endif
 639
 640 /*
 641  * Reserve memory for kdump kernel to be loaded with kexec
 642  */
 643 static void __init reserve_crashkernel(void)
 644 {
 645 #ifdef CONFIG_CRASH_DUMP
 646         unsigned long long crash_base, crash_size;
 647         phys_addr_t low, high;
 648         int rc;
 649
 650         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 651                                &crash_base);
 652
 653         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 654         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 655         if (rc || crash_size == 0)
 656                 return;
 657
 658         if (memblock.memory.regions[0].size < crash_size) {
 659                 pr_info("crashkernel reservation failed: %s\n",
 660                         "first memory chunk must be at least crashkernel size");
 661                 return;
 662         }
 663
 664         low = crash_base ?: oldmem_data.start;
 665         high = low + crash_size;
 666         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 667                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 668                 crash_base = low;
 669         } else {
 670                 /* Find suitable area in free memory */
 671                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 672                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 673
 674                 if (crash_base && crash_base < low) {
 675                         pr_info("crashkernel reservation failed: %s\n",
 676                                 "crash_base too low");
 677                         return;
 678                 }
 679                 low = crash_base ?: low;
 680                 crash_base = memblock_phys_alloc_range(crash_size,
 681                                                        KEXEC_CRASH_MEM_ALIGN,
 682                                                        low, high);
 683         }
 684
 685         if (!crash_base) {
 686                 pr_info("crashkernel reservation failed: %s\n",
 687                         "no suitable area found");
 688                 return;
 689         }
 690
 691         if (register_memory_notifier(&kdump_mem_nb)) {
 692                 memblock_phys_free(crash_base, crash_size);
 693                 return;
 694         }
 695
 696         if (!oldmem_data.start && MACHINE_IS_VM)
 697                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 698         crashk_res.start = crash_base;
 699         crashk_res.end = crash_base + crash_size - 1;
 700         memblock_remove(crash_base, crash_size);
 701         pr_info("Reserving %lluMB of memory at %lluMB "
 702                 "for crashkernel (System RAM: %luMB)\n",
 703                 crash_size >> 20, crash_base >> 20,
 704                 (unsigned long)memblock.memory.total_size >> 20);
 705         os_info_crashkernel_add(crash_base, crash_size);
 706 #endif
 707 }
 708
 709 /*
 710  * Reserve the initrd from being used by memblock
 711  */
 712 static void __init reserve_initrd(void)
 713 {
 714 #ifdef CONFIG_BLK_DEV_INITRD
 715         if (!initrd_data.start || !initrd_data.size)
 716                 return;
 717         initrd_start = (unsigned long)__va(initrd_data.start);
 718         initrd_end = initrd_start + initrd_data.size;
 719         memblock_reserve(initrd_data.start, initrd_data.size);
 720 #endif
 721 }
 722
 723 /*
 724  * Reserve the memory area used to pass the certificate lists
 725  */
 726 static void __init reserve_certificate_list(void)
 727 {
 728         if (ipl_cert_list_addr)
 729                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 730 }
 731
 732 static void __init reserve_mem_detect_info(void)
 733 {
 734         unsigned long start, size;
 735
 736         get_mem_detect_reserved(&start, &size);
 737         if (size)
 738                 memblock_reserve(start, size);
 739 }
 740
 741 static void __init free_mem_detect_info(void)
 742 {
 743         unsigned long start, size;
 744
 745         get_mem_detect_reserved(&start, &size);
 746         if (size)
 747                 memblock_phys_free(start, size);
 748 }
 749
 750 static const char * __init get_mem_info_source(void)
 751 {
 752         switch (mem_detect.info_source) {
 753         case MEM_DETECT_SCLP_STOR_INFO:
 754                 return "sclp storage info";
 755         case MEM_DETECT_DIAG260:
 756                 return "diag260";
 757         case MEM_DETECT_SCLP_READ_INFO:
 758                 return "sclp read info";
 759         case MEM_DETECT_BIN_SEARCH:
 760                 return "binary search";
 761         }
 762         return "none";
 763 }
 764
 765 static void __init memblock_add_mem_detect_info(void)
 766 {
 767         unsigned long start, end;
 768         int i;
 769
 770         pr_debug("physmem info source: %s (%hhd)\n",
 771                  get_mem_info_source(), mem_detect.info_source);
 772         /* keep memblock lists close to the kernel */
 773         memblock_set_bottom_up(true);
 774         for_each_mem_detect_block(i, &start, &end) {
 775                 memblock_add(start, end - start);
 776                 memblock_physmem_add(start, end - start);
 777         }
 778         memblock_set_bottom_up(false);
 779         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 780 }
 781
 782 /*
 783  * Check for initrd being in usable memory
 784  */
 785 static void __init check_initrd(void)
 786 {
 787 #ifdef CONFIG_BLK_DEV_INITRD
 788         if (initrd_data.start && initrd_data.size &&
 789             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 790                 pr_err("The initial RAM disk does not fit into the memory\n");
 791                 memblock_phys_free(initrd_data.start, initrd_data.size);
 792                 initrd_start = initrd_end = 0;
 793         }
 794 #endif
 795 }
 796
 797 /*
 798  * Reserve memory used for lowcore/command line/kernel image.
 799  */
 800 static void __init reserve_kernel(void)
 801 {
 802         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 803         memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 804         memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 805         memblock_reserve(__amode31_base, __eamode31 - __samode31);
 806         memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 807         memblock_reserve(__pa(_stext), _end - _stext);
 808 }
 809
 810 static void __init setup_memory(void)
 811 {
 812         phys_addr_t start, end;
 813         u64 i;
 814
 815         /*
 816          * Init storage key for present memory
 817          */
 818         for_each_mem_range(i, &start, &end)
 819                 storage_key_init_range(start, end);
 820
 821         psw_set_key(PAGE_DEFAULT_KEY);
 822 }
 823
 824 static void __init relocate_amode31_section(void)
 825 {
 826         unsigned long amode31_size = __eamode31 - __samode31;
 827         long amode31_offset = __amode31_base - __samode31;
 828         long *ptr;
 829
 830         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 831
 832         /* Move original AMODE31 section to the new one */
 833         memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 834         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 835         memset((void *)__samode31, 0, amode31_size);
 836
 837         /* Update all AMODE31 region references */
 838         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 839                 *ptr += amode31_offset;
 840 }
 841
 842 /* This must be called after AMODE31 relocation */
 843 static void __init setup_cr(void)
 844 {
 845         union ctlreg2 cr2;
 846         union ctlreg5 cr5;
 847         union ctlreg15 cr15;
 848
 849         __ctl_duct[1] = (unsigned long)__ctl_aste;
 850         __ctl_duct[2] = (unsigned long)__ctl_aste;
 851         __ctl_duct[4] = (unsigned long)__ctl_duald;
 852
 853         /* Update control registers CR2, CR5 and CR15 */
 854         __ctl_store(cr2.val, 2, 2);
 855         __ctl_store(cr5.val, 5, 5);
 856         __ctl_store(cr15.val, 15, 15);
 857         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 858         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 859         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 860         __ctl_load(cr2.val, 2, 2);
 861         __ctl_load(cr5.val, 5, 5);
 862         __ctl_load(cr15.val, 15, 15);
 863 }
 864
 865 /*
 866  * Add system information as device randomness
 867  */
 868 static void __init setup_randomness(void)
 869 {
 870         struct sysinfo_3_2_2 *vmms;
 871
 872         vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 873         if (!vmms)
 874                 panic("Failed to allocate memory for sysinfo structure\n");
 875         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 876                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 877         memblock_free(vmms, PAGE_SIZE);
 878 }
 879
 880 /*
 881  * Find the correct size for the task_struct. This depends on
 882  * the size of the struct fpu at the end of the thread_struct
 883  * which is embedded in the task_struct.
 884  */
 885 static void __init setup_task_size(void)
 886 {
 887         int task_size = sizeof(struct task_struct);
 888
 889         if (!MACHINE_HAS_VX) {
 890                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 891                 task_size += sizeof(freg_t) * __NUM_FPRS;
 892         }
 893         arch_task_struct_size = task_size;
 894 }
 895
 896 /*
 897  * Issue diagnose 318 to set the control program name and
 898  * version codes.
 899  */
 900 static void __init setup_control_program_code(void)
 901 {
 902         union diag318_info diag318_info = {
 903                 .cpnc = CPNC_LINUX,
 904                 .cpvc = 0,
 905         };
 906
 907         if (!sclp.has_diag318)
 908                 return;
 909
 910         diag_stat_inc(DIAG_STAT_X318);
 911         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 912 }
 913
 914 /*
 915  * Print the component list from the IPL report
 916  */
 917 static void __init log_component_list(void)
 918 {
 919         struct ipl_rb_component_entry *ptr, *end;
 920         char *str;
 921
 922         if (!early_ipl_comp_list_addr)
 923                 return;
 924         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 925                 pr_info("Linux is running with Secure-IPL enabled\n");
 926         else
 927                 pr_info("Linux is running with Secure-IPL disabled\n");
 928         ptr = (void *) early_ipl_comp_list_addr;
 929         end = (void *) ptr + early_ipl_comp_list_size;
 930         pr_info("The IPL report contains the following components:\n");
 931         while (ptr < end) {
 932                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 933                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 934                                 str = "signed, verified";
 935                         else
 936                                 str = "signed, verification failed";
 937                 } else {
 938                         str = "not signed";
 939                 }
 940                 pr_info("%016llx - %016llx (%s)\n",
 941                         ptr->addr, ptr->addr + ptr->len, str);
 942                 ptr++;
 943         }
 944 }
 945
 946 /*
 947  * Setup function called from init/main.c just after the banner
 948  * was printed.
 949  */
 950
 951 void __init setup_arch(char **cmdline_p)
 952 {
 953         /*
 954          * print what head.S has found out about the machine
 955          */
 956         if (MACHINE_IS_VM)
 957                 pr_info("Linux is running as a z/VM "
 958                         "guest operating system in 64-bit mode\n");
 959         else if (MACHINE_IS_KVM)
 960                 pr_info("Linux is running under KVM in 64-bit mode\n");
 961         else if (MACHINE_IS_LPAR)
 962                 pr_info("Linux is running natively in 64-bit mode\n");
 963         else
 964                 pr_info("Linux is running as a guest in 64-bit mode\n");
 965
 966         log_component_list();
 967
 968         /* Have one command line that is parsed and saved in /proc/cmdline */
 969         /* boot_command_line has been already set up in early.c */
 970         *cmdline_p = boot_command_line;
 971
 972         ROOT_DEV = Root_RAM0;
 973
 974         setup_initial_init_mm(_text, _etext, _edata, _end);
 975
 976         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 977                 nospec_auto_detect();
 978
 979         jump_label_init();
 980         parse_early_param();
 981 #ifdef CONFIG_CRASH_DUMP
 982         /* Deactivate elfcorehdr= kernel parameter */
 983         elfcorehdr_addr = ELFCORE_ADDR_MAX;
 984 #endif
 985
 986         os_info_init();
 987         setup_ipl();
 988         setup_task_size();
 989         setup_control_program_code();
 990
 991         /* Do some memory reservations *before* memory is added to memblock */
 992         reserve_kernel();
 993         reserve_initrd();
 994         reserve_certificate_list();
 995         reserve_mem_detect_info();
 996         memblock_set_current_limit(ident_map_size);
 997         memblock_allow_resize();
 998
 999         /* Get information about *all* installed memory */
1000         memblock_add_mem_detect_info();
1001
1002         free_mem_detect_info();
1003         setup_memory_end();
1004         memblock_dump_all();
1005         setup_memory();
1006
1007         relocate_amode31_section();
1008         setup_cr();
1009         setup_uv();
1010         dma_contiguous_reserve(ident_map_size);
1011         vmcp_cma_reserve();
1012         if (MACHINE_HAS_EDAT2)
1013                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1014
1015         check_initrd();
1016         reserve_crashkernel();
1017 #ifdef CONFIG_CRASH_DUMP
1018         /*
1019          * Be aware that smp_save_dump_cpus() triggers a system reset.
1020          * Therefore CPU and device initialization should be done afterwards.
1021          */
1022         smp_save_dump_cpus();
1023 #endif
1024
1025         setup_resources();
1026         setup_lowcore_dat_off();
1027         smp_fill_possible_mask();
1028         cpu_detect_mhz_feature();
1029         cpu_init();
1030         numa_setup();
1031         smp_detect_cpus();
1032         topology_init_early();
1033
1034         if (test_facility(193))
1035                 static_branch_enable(&cpu_has_bear);
1036
1037         /*
1038          * Create kernel page tables and switch to virtual addressing.
1039          */
1040         paging_init();
1041
1042         /*
1043          * After paging_init created the kernel page table, the new PSWs
1044          * in lowcore can now run with DAT enabled.
1045          */
1046         setup_lowcore_dat_on();
1047
1048         /* Setup default console */
1049         conmode_default();
1050         set_preferred_console();
1051
1052         apply_alternative_instructions();
1053         if (IS_ENABLED(CONFIG_EXPOLINE))
1054                 nospec_init_branches();
1055
1056         /* Setup zfcp/nvme dump support */
1057         setup_zfcpdump();
1058
1059         /* Add system specific data to the random pool */
1060         setup_randomness();
1061 }