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/abs_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/maccess.h>
  78 #include <asm/uv.h>
  79 #include <asm/asm-offsets.h>
  80 #include "entry.h"
  81
  82 /*
  83  * Machine setup..
  84  */
  85 unsigned int console_mode = 0;
  86 EXPORT_SYMBOL(console_mode);
  87
  88 unsigned int console_devno = -1;
  89 EXPORT_SYMBOL(console_devno);
  90
  91 unsigned int console_irq = -1;
  92 EXPORT_SYMBOL(console_irq);
  93
  94 /*
  95  * Some code and data needs to stay below 2 GB, even when the kernel would be
  96  * relocated above 2 GB, because it has to use 31 bit addresses.
  97  * Such code and data is part of the .amode31 section.
  98  */
  99 unsigned long __amode31_ref __samode31 = (unsigned long)&_samode31;
 100 unsigned long __amode31_ref __eamode31 = (unsigned long)&_eamode31;
 101 unsigned long __amode31_ref __stext_amode31 = (unsigned long)&_stext_amode31;
 102 unsigned long __amode31_ref __etext_amode31 = (unsigned long)&_etext_amode31;
 103 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
 104 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
 105
 106 /*
 107  * Control registers CR2, CR5 and CR15 are initialized with addresses
 108  * of tables that must be placed below 2G which is handled by the AMODE31
 109  * sections.
 110  * Because the AMODE31 sections are relocated below 2G at startup,
 111  * the content of control registers CR2, CR5 and CR15 must be updated
 112  * with new addresses after the relocation. The initial initialization of
 113  * control registers occurs in head64.S and then gets updated again after AMODE31
 114  * relocation. We must access the relevant AMODE31 tables indirectly via
 115  * pointers placed in the .amode31.refs linker section. Those pointers get
 116  * updated automatically during AMODE31 relocation and always contain a valid
 117  * address within AMODE31 sections.
 118  */
 119
 120 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
 121
 122 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
 123         [1] = 0xffffffffffffffff
 124 };
 125
 126 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
 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         0x80000000, 0, 0, 0
 135 };
 136
 137 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
 138         0, 0, 0x89000000, 0,
 139         0, 0, 0x8a000000, 0
 140 };
 141
 142 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
 143 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
 144 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
 145 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
 146
 147 int __bootdata(noexec_disabled);
 148 unsigned long __bootdata(ident_map_size);
 149 struct mem_detect_info __bootdata(mem_detect);
 150 struct initrd_data __bootdata(initrd_data);
 151
 152 unsigned long __bootdata_preserved(__kaslr_offset);
 153 unsigned long __bootdata(__amode31_base);
 154 unsigned int __bootdata_preserved(zlib_dfltcc_support);
 155 EXPORT_SYMBOL(zlib_dfltcc_support);
 156 u64 __bootdata_preserved(stfle_fac_list[16]);
 157 EXPORT_SYMBOL(stfle_fac_list);
 158 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 159 struct oldmem_data __bootdata_preserved(oldmem_data);
 160
 161 unsigned long VMALLOC_START;
 162 EXPORT_SYMBOL(VMALLOC_START);
 163
 164 unsigned long VMALLOC_END;
 165 EXPORT_SYMBOL(VMALLOC_END);
 166
 167 struct page *vmemmap;
 168 EXPORT_SYMBOL(vmemmap);
 169 unsigned long vmemmap_size;
 170
 171 unsigned long MODULES_VADDR;
 172 unsigned long MODULES_END;
 173
 174 /* An array with a pointer to the lowcore of every CPU. */
 175 struct lowcore *lowcore_ptr[NR_CPUS];
 176 EXPORT_SYMBOL(lowcore_ptr);
 177
 178 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
 179
 180 /*
 181  * The Write Back bit position in the physaddr is given by the SLPC PCI.
 182  * Leaving the mask zero always uses write through which is safe
 183  */
 184 unsigned long mio_wb_bit_mask __ro_after_init;
 185
 186 /*
 187  * This is set up by the setup-routine at boot-time
 188  * for S390 need to find out, what we have to setup
 189  * using address 0x10400 ...
 190  */
 191
 192 #include <asm/setup.h>
 193
 194 /*
 195  * condev= and conmode= setup parameter.
 196  */
 197
 198 static int __init condev_setup(char *str)
 199 {
 200         int vdev;
 201
 202         vdev = simple_strtoul(str, &str, 0);
 203         if (vdev >= 0 && vdev < 65536) {
 204                 console_devno = vdev;
 205                 console_irq = -1;
 206         }
 207         return 1;
 208 }
 209
 210 __setup("condev=", condev_setup);
 211
 212 static void __init set_preferred_console(void)
 213 {
 214         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 215                 add_preferred_console("ttyS", 0, NULL);
 216         else if (CONSOLE_IS_3270)
 217                 add_preferred_console("tty3270", 0, NULL);
 218         else if (CONSOLE_IS_VT220)
 219                 add_preferred_console("ttysclp", 0, NULL);
 220         else if (CONSOLE_IS_HVC)
 221                 add_preferred_console("hvc", 0, NULL);
 222 }
 223
 224 static int __init conmode_setup(char *str)
 225 {
 226 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 227         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 228                 SET_CONSOLE_SCLP;
 229 #endif
 230 #if defined(CONFIG_TN3215_CONSOLE)
 231         if (!strcmp(str, "3215"))
 232                 SET_CONSOLE_3215;
 233 #endif
 234 #if defined(CONFIG_TN3270_CONSOLE)
 235         if (!strcmp(str, "3270"))
 236                 SET_CONSOLE_3270;
 237 #endif
 238         set_preferred_console();
 239         return 1;
 240 }
 241
 242 __setup("conmode=", conmode_setup);
 243
 244 static void __init conmode_default(void)
 245 {
 246         char query_buffer[1024];
 247         char *ptr;
 248
 249         if (MACHINE_IS_VM) {
 250                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 251                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 252                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 253                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 254                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 255                 ptr = strstr(query_buffer, "CONMODE");
 256                 /*
 257                  * Set the conmode to 3215 so that the device recognition
 258                  * will set the cu_type of the console to 3215. If the
 259                  * conmode is 3270 and we don't set it back then both
 260                  * 3215 and the 3270 driver will try to access the console
 261                  * device (3215 as console and 3270 as normal tty).
 262                  */
 263                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 264                 if (ptr == NULL) {
 265 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 266                         SET_CONSOLE_SCLP;
 267 #endif
 268                         return;
 269                 }
 270                 if (str_has_prefix(ptr + 8, "3270")) {
 271 #if defined(CONFIG_TN3270_CONSOLE)
 272                         SET_CONSOLE_3270;
 273 #elif defined(CONFIG_TN3215_CONSOLE)
 274                         SET_CONSOLE_3215;
 275 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 276                         SET_CONSOLE_SCLP;
 277 #endif
 278                 } else if (str_has_prefix(ptr + 8, "3215")) {
 279 #if defined(CONFIG_TN3215_CONSOLE)
 280                         SET_CONSOLE_3215;
 281 #elif defined(CONFIG_TN3270_CONSOLE)
 282                         SET_CONSOLE_3270;
 283 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 284                         SET_CONSOLE_SCLP;
 285 #endif
 286                 }
 287         } else if (MACHINE_IS_KVM) {
 288                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 289                         SET_CONSOLE_VT220;
 290                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 291                         SET_CONSOLE_SCLP;
 292                 else
 293                         SET_CONSOLE_HVC;
 294         } else {
 295 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 296                 SET_CONSOLE_SCLP;
 297 #endif
 298         }
 299 }
 300
 301 #ifdef CONFIG_CRASH_DUMP
 302 static void __init setup_zfcpdump(void)
 303 {
 304         if (!is_ipl_type_dump())
 305                 return;
 306         if (oldmem_data.start)
 307                 return;
 308         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 309         console_loglevel = 2;
 310 }
 311 #else
 312 static inline void setup_zfcpdump(void) {}
 313 #endif /* CONFIG_CRASH_DUMP */
 314
 315  /*
 316  * Reboot, halt and power_off stubs. They just call _machine_restart,
 317  * _machine_halt or _machine_power_off.
 318  */
 319
 320 void machine_restart(char *command)
 321 {
 322         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 323                 /*
 324                  * Only unblank the console if we are called in enabled
 325                  * context or a bust_spinlocks cleared the way for us.
 326                  */
 327                 console_unblank();
 328         _machine_restart(command);
 329 }
 330
 331 void machine_halt(void)
 332 {
 333         if (!in_interrupt() || oops_in_progress)
 334                 /*
 335                  * Only unblank the console if we are called in enabled
 336                  * context or a bust_spinlocks cleared the way for us.
 337                  */
 338                 console_unblank();
 339         _machine_halt();
 340 }
 341
 342 void machine_power_off(void)
 343 {
 344         if (!in_interrupt() || oops_in_progress)
 345                 /*
 346                  * Only unblank the console if we are called in enabled
 347                  * context or a bust_spinlocks cleared the way for us.
 348                  */
 349                 console_unblank();
 350         _machine_power_off();
 351 }
 352
 353 /*
 354  * Dummy power off function.
 355  */
 356 void (*pm_power_off)(void) = machine_power_off;
 357 EXPORT_SYMBOL_GPL(pm_power_off);
 358
 359 void *restart_stack;
 360
 361 unsigned long stack_alloc(void)
 362 {
 363 #ifdef CONFIG_VMAP_STACK
 364         void *ret;
 365
 366         ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
 367                              NUMA_NO_NODE, __builtin_return_address(0));
 368         kmemleak_not_leak(ret);
 369         return (unsigned long)ret;
 370 #else
 371         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 372 #endif
 373 }
 374
 375 void stack_free(unsigned long stack)
 376 {
 377 #ifdef CONFIG_VMAP_STACK
 378         vfree((void *) stack);
 379 #else
 380         free_pages(stack, THREAD_SIZE_ORDER);
 381 #endif
 382 }
 383
 384 int __init arch_early_irq_init(void)
 385 {
 386         unsigned long stack;
 387
 388         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 389         if (!stack)
 390                 panic("Couldn't allocate async stack");
 391         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 392         return 0;
 393 }
 394
 395 void __init arch_call_rest_init(void)
 396 {
 397         unsigned long stack;
 398
 399         smp_reinit_ipl_cpu();
 400         stack = stack_alloc();
 401         if (!stack)
 402                 panic("Couldn't allocate kernel stack");
 403         current->stack = (void *) stack;
 404 #ifdef CONFIG_VMAP_STACK
 405         current->stack_vm_area = (void *) stack;
 406 #endif
 407         set_task_stack_end_magic(current);
 408         stack += STACK_INIT_OFFSET;
 409         S390_lowcore.kernel_stack = stack;
 410         call_on_stack_noreturn(rest_init, stack);
 411 }
 412
 413 static void __init setup_lowcore_dat_off(void)
 414 {
 415         unsigned long int_psw_mask = PSW_KERNEL_BITS;
 416         struct lowcore *abs_lc, *lc;
 417         unsigned long mcck_stack;
 418         unsigned long flags;
 419
 420         if (IS_ENABLED(CONFIG_KASAN))
 421                 int_psw_mask |= PSW_MASK_DAT;
 422
 423         /*
 424          * Setup lowcore for boot cpu
 425          */
 426         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 427         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 428         if (!lc)
 429                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 430                       __func__, sizeof(*lc), sizeof(*lc));
 431
 432         lc->restart_psw.mask = PSW_KERNEL_BITS;
 433         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 434         lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 435         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 436         lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 437         lc->svc_new_psw.addr = (unsigned long) system_call;
 438         lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 439         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 440         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 441         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 442         lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 443         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 444         lc->clock_comparator = clock_comparator_max;
 445         lc->nodat_stack = ((unsigned long) &init_thread_union)
 446                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 447         lc->current_task = (unsigned long)&init_task;
 448         lc->lpp = LPP_MAGIC;
 449         lc->machine_flags = S390_lowcore.machine_flags;
 450         lc->preempt_count = S390_lowcore.preempt_count;
 451         nmi_alloc_mcesa_early(&lc->mcesad);
 452         lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 453         lc->exit_timer = S390_lowcore.exit_timer;
 454         lc->user_timer = S390_lowcore.user_timer;
 455         lc->system_timer = S390_lowcore.system_timer;
 456         lc->steal_timer = S390_lowcore.steal_timer;
 457         lc->last_update_timer = S390_lowcore.last_update_timer;
 458         lc->last_update_clock = S390_lowcore.last_update_clock;
 459
 460         /*
 461          * Allocate the global restart stack which is the same for
 462          * all CPUs in cast *one* of them does a PSW restart.
 463          */
 464         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 465         if (!restart_stack)
 466                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 467                       __func__, THREAD_SIZE, THREAD_SIZE);
 468         restart_stack += STACK_INIT_OFFSET;
 469
 470         /*
 471          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 472          * restart data to the absolute zero lowcore. This is necessary if
 473          * PSW restart is done on an offline CPU that has lowcore zero.
 474          */
 475         lc->restart_stack = (unsigned long) restart_stack;
 476         lc->restart_fn = (unsigned long) do_restart;
 477         lc->restart_data = 0;
 478         lc->restart_source = -1U;
 479
 480         abs_lc = get_abs_lowcore(&flags);
 481         abs_lc->restart_stack = lc->restart_stack;
 482         abs_lc->restart_fn = lc->restart_fn;
 483         abs_lc->restart_data = lc->restart_data;
 484         abs_lc->restart_source = lc->restart_source;
 485         abs_lc->restart_psw = lc->restart_psw;
 486         abs_lc->mcesad = lc->mcesad;
 487         put_abs_lowcore(abs_lc, flags);
 488
 489         mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 490         if (!mcck_stack)
 491                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 492                       __func__, THREAD_SIZE, THREAD_SIZE);
 493         lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 494
 495         lc->spinlock_lockval = arch_spin_lockval(0);
 496         lc->spinlock_index = 0;
 497         arch_spin_lock_setup(0);
 498         lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 499         lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 500         lc->preempt_count = PREEMPT_DISABLED;
 501
 502         set_prefix(__pa(lc));
 503         lowcore_ptr[0] = lc;
 504 }
 505
 506 static void __init setup_lowcore_dat_on(void)
 507 {
 508         struct lowcore *abs_lc;
 509         unsigned long flags;
 510
 511         __ctl_clear_bit(0, 28);
 512         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 513         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 514         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 515         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 516         __ctl_set_bit(0, 28);
 517         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 518         if (abs_lowcore_map(0, lowcore_ptr[0], true))
 519                 panic("Couldn't setup absolute lowcore");
 520         abs_lowcore_mapped = true;
 521         abs_lc = get_abs_lowcore(&flags);
 522         abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
 523         abs_lc->program_new_psw = S390_lowcore.program_new_psw;
 524         memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area,
 525                sizeof(abs_lc->cregs_save_area));
 526         put_abs_lowcore(abs_lc, flags);
 527 }
 528
 529 static struct resource code_resource = {
 530         .name  = "Kernel code",
 531         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 532 };
 533
 534 static struct resource data_resource = {
 535         .name = "Kernel data",
 536         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 537 };
 538
 539 static struct resource bss_resource = {
 540         .name = "Kernel bss",
 541         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 542 };
 543
 544 static struct resource __initdata *standard_resources[] = {
 545         &code_resource,
 546         &data_resource,
 547         &bss_resource,
 548 };
 549
 550 static void __init setup_resources(void)
 551 {
 552         struct resource *res, *std_res, *sub_res;
 553         phys_addr_t start, end;
 554         int j;
 555         u64 i;
 556
 557         code_resource.start = (unsigned long) _text;
 558         code_resource.end = (unsigned long) _etext - 1;
 559         data_resource.start = (unsigned long) _etext;
 560         data_resource.end = (unsigned long) _edata - 1;
 561         bss_resource.start = (unsigned long) __bss_start;
 562         bss_resource.end = (unsigned long) __bss_stop - 1;
 563
 564         for_each_mem_range(i, &start, &end) {
 565                 res = memblock_alloc(sizeof(*res), 8);
 566                 if (!res)
 567                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 568                               __func__, sizeof(*res), 8);
 569                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 570
 571                 res->name = "System RAM";
 572                 res->start = start;
 573                 /*
 574                  * In memblock, end points to the first byte after the
 575                  * range while in resourses, end points to the last byte in
 576                  * the range.
 577                  */
 578                 res->end = end - 1;
 579                 request_resource(&iomem_resource, res);
 580
 581                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 582                         std_res = standard_resources[j];
 583                         if (std_res->start < res->start ||
 584                             std_res->start > res->end)
 585                                 continue;
 586                         if (std_res->end > res->end) {
 587                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 588                                 if (!sub_res)
 589                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 590                                               __func__, sizeof(*sub_res), 8);
 591                                 *sub_res = *std_res;
 592                                 sub_res->end = res->end;
 593                                 std_res->start = res->end + 1;
 594                                 request_resource(res, sub_res);
 595                         } else {
 596                                 request_resource(res, std_res);
 597                         }
 598                 }
 599         }
 600 #ifdef CONFIG_CRASH_DUMP
 601         /*
 602          * Re-add removed crash kernel memory as reserved memory. This makes
 603          * sure it will be mapped with the identity mapping and struct pages
 604          * will be created, so it can be resized later on.
 605          * However add it later since the crash kernel resource should not be
 606          * part of the System RAM resource.
 607          */
 608         if (crashk_res.end) {
 609                 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 610                                   0, MEMBLOCK_NONE);
 611                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 612                 insert_resource(&iomem_resource, &crashk_res);
 613         }
 614 #endif
 615 }
 616
 617 static void __init setup_memory_end(void)
 618 {
 619         memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 620         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 621         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 622 }
 623
 624 #ifdef CONFIG_CRASH_DUMP
 625
 626 /*
 627  * When kdump is enabled, we have to ensure that no memory from the area
 628  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 629  * the crashkernel memory region when kdump is triggered. The crashkernel
 630  * memory region can never get offlined (pages are unmovable).
 631  */
 632 static int kdump_mem_notifier(struct notifier_block *nb,
 633                               unsigned long action, void *data)
 634 {
 635         struct memory_notify *arg = data;
 636
 637         if (action != MEM_GOING_OFFLINE)
 638                 return NOTIFY_OK;
 639         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 640                 return NOTIFY_BAD;
 641         return NOTIFY_OK;
 642 }
 643
 644 static struct notifier_block kdump_mem_nb = {
 645         .notifier_call = kdump_mem_notifier,
 646 };
 647
 648 #endif
 649
 650 /*
 651  * Reserve memory for kdump kernel to be loaded with kexec
 652  */
 653 static void __init reserve_crashkernel(void)
 654 {
 655 #ifdef CONFIG_CRASH_DUMP
 656         unsigned long long crash_base, crash_size;
 657         phys_addr_t low, high;
 658         int rc;
 659
 660         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 661                                &crash_base);
 662
 663         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 664         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 665         if (rc || crash_size == 0)
 666                 return;
 667
 668         if (memblock.memory.regions[0].size < crash_size) {
 669                 pr_info("crashkernel reservation failed: %s\n",
 670                         "first memory chunk must be at least crashkernel size");
 671                 return;
 672         }
 673
 674         low = crash_base ?: oldmem_data.start;
 675         high = low + crash_size;
 676         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 677                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 678                 crash_base = low;
 679         } else {
 680                 /* Find suitable area in free memory */
 681                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 682                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 683
 684                 if (crash_base && crash_base < low) {
 685                         pr_info("crashkernel reservation failed: %s\n",
 686                                 "crash_base too low");
 687                         return;
 688                 }
 689                 low = crash_base ?: low;
 690                 crash_base = memblock_phys_alloc_range(crash_size,
 691                                                        KEXEC_CRASH_MEM_ALIGN,
 692                                                        low, high);
 693         }
 694
 695         if (!crash_base) {
 696                 pr_info("crashkernel reservation failed: %s\n",
 697                         "no suitable area found");
 698                 return;
 699         }
 700
 701         if (register_memory_notifier(&kdump_mem_nb)) {
 702                 memblock_phys_free(crash_base, crash_size);
 703                 return;
 704         }
 705
 706         if (!oldmem_data.start && MACHINE_IS_VM)
 707                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 708         crashk_res.start = crash_base;
 709         crashk_res.end = crash_base + crash_size - 1;
 710         memblock_remove(crash_base, crash_size);
 711         pr_info("Reserving %lluMB of memory at %lluMB "
 712                 "for crashkernel (System RAM: %luMB)\n",
 713                 crash_size >> 20, crash_base >> 20,
 714                 (unsigned long)memblock.memory.total_size >> 20);
 715         os_info_crashkernel_add(crash_base, crash_size);
 716 #endif
 717 }
 718
 719 /*
 720  * Reserve the initrd from being used by memblock
 721  */
 722 static void __init reserve_initrd(void)
 723 {
 724 #ifdef CONFIG_BLK_DEV_INITRD
 725         if (!initrd_data.start || !initrd_data.size)
 726                 return;
 727         initrd_start = (unsigned long)__va(initrd_data.start);
 728         initrd_end = initrd_start + initrd_data.size;
 729         memblock_reserve(initrd_data.start, initrd_data.size);
 730 #endif
 731 }
 732
 733 /*
 734  * Reserve the memory area used to pass the certificate lists
 735  */
 736 static void __init reserve_certificate_list(void)
 737 {
 738         if (ipl_cert_list_addr)
 739                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 740 }
 741
 742 static void __init reserve_mem_detect_info(void)
 743 {
 744         unsigned long start, size;
 745
 746         get_mem_detect_reserved(&start, &size);
 747         if (size)
 748                 memblock_reserve(start, size);
 749 }
 750
 751 static void __init free_mem_detect_info(void)
 752 {
 753         unsigned long start, size;
 754
 755         get_mem_detect_reserved(&start, &size);
 756         if (size)
 757                 memblock_phys_free(start, size);
 758 }
 759
 760 static const char * __init get_mem_info_source(void)
 761 {
 762         switch (mem_detect.info_source) {
 763         case MEM_DETECT_SCLP_STOR_INFO:
 764                 return "sclp storage info";
 765         case MEM_DETECT_DIAG260:
 766                 return "diag260";
 767         case MEM_DETECT_SCLP_READ_INFO:
 768                 return "sclp read info";
 769         case MEM_DETECT_BIN_SEARCH:
 770                 return "binary search";
 771         }
 772         return "none";
 773 }
 774
 775 static void __init memblock_add_mem_detect_info(void)
 776 {
 777         unsigned long start, end;
 778         int i;
 779
 780         pr_debug("physmem info source: %s (%hhd)\n",
 781                  get_mem_info_source(), mem_detect.info_source);
 782         /* keep memblock lists close to the kernel */
 783         memblock_set_bottom_up(true);
 784         for_each_mem_detect_block(i, &start, &end) {
 785                 memblock_add(start, end - start);
 786                 memblock_physmem_add(start, end - start);
 787         }
 788         memblock_set_bottom_up(false);
 789         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 790 }
 791
 792 /*
 793  * Check for initrd being in usable memory
 794  */
 795 static void __init check_initrd(void)
 796 {
 797 #ifdef CONFIG_BLK_DEV_INITRD
 798         if (initrd_data.start && initrd_data.size &&
 799             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 800                 pr_err("The initial RAM disk does not fit into the memory\n");
 801                 memblock_phys_free(initrd_data.start, initrd_data.size);
 802                 initrd_start = initrd_end = 0;
 803         }
 804 #endif
 805 }
 806
 807 /*
 808  * Reserve memory used for lowcore/command line/kernel image.
 809  */
 810 static void __init reserve_kernel(void)
 811 {
 812         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 813         memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 814         memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 815         memblock_reserve(__amode31_base, __eamode31 - __samode31);
 816         memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 817         memblock_reserve(__pa(_stext), _end - _stext);
 818 }
 819
 820 static void __init setup_memory(void)
 821 {
 822         phys_addr_t start, end;
 823         u64 i;
 824
 825         /*
 826          * Init storage key for present memory
 827          */
 828         for_each_mem_range(i, &start, &end)
 829                 storage_key_init_range(start, end);
 830
 831         psw_set_key(PAGE_DEFAULT_KEY);
 832 }
 833
 834 static void __init relocate_amode31_section(void)
 835 {
 836         unsigned long amode31_size = __eamode31 - __samode31;
 837         long amode31_offset = __amode31_base - __samode31;
 838         long *ptr;
 839
 840         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 841
 842         /* Move original AMODE31 section to the new one */
 843         memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 844         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 845         memset((void *)__samode31, 0, amode31_size);
 846
 847         /* Update all AMODE31 region references */
 848         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 849                 *ptr += amode31_offset;
 850 }
 851
 852 /* This must be called after AMODE31 relocation */
 853 static void __init setup_cr(void)
 854 {
 855         union ctlreg2 cr2;
 856         union ctlreg5 cr5;
 857         union ctlreg15 cr15;
 858
 859         __ctl_duct[1] = (unsigned long)__ctl_aste;
 860         __ctl_duct[2] = (unsigned long)__ctl_aste;
 861         __ctl_duct[4] = (unsigned long)__ctl_duald;
 862
 863         /* Update control registers CR2, CR5 and CR15 */
 864         __ctl_store(cr2.val, 2, 2);
 865         __ctl_store(cr5.val, 5, 5);
 866         __ctl_store(cr15.val, 15, 15);
 867         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 868         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 869         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 870         __ctl_load(cr2.val, 2, 2);
 871         __ctl_load(cr5.val, 5, 5);
 872         __ctl_load(cr15.val, 15, 15);
 873 }
 874
 875 /*
 876  * Add system information as device randomness
 877  */
 878 static void __init setup_randomness(void)
 879 {
 880         struct sysinfo_3_2_2 *vmms;
 881
 882         vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 883         if (!vmms)
 884                 panic("Failed to allocate memory for sysinfo structure\n");
 885         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 886                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 887         memblock_free(vmms, PAGE_SIZE);
 888
 889         if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
 890                 static_branch_enable(&s390_arch_random_available);
 891 }
 892
 893 /*
 894  * Find the correct size for the task_struct. This depends on
 895  * the size of the struct fpu at the end of the thread_struct
 896  * which is embedded in the task_struct.
 897  */
 898 static void __init setup_task_size(void)
 899 {
 900         int task_size = sizeof(struct task_struct);
 901
 902         if (!MACHINE_HAS_VX) {
 903                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 904                 task_size += sizeof(freg_t) * __NUM_FPRS;
 905         }
 906         arch_task_struct_size = task_size;
 907 }
 908
 909 /*
 910  * Issue diagnose 318 to set the control program name and
 911  * version codes.
 912  */
 913 static void __init setup_control_program_code(void)
 914 {
 915         union diag318_info diag318_info = {
 916                 .cpnc = CPNC_LINUX,
 917                 .cpvc = 0,
 918         };
 919
 920         if (!sclp.has_diag318)
 921                 return;
 922
 923         diag_stat_inc(DIAG_STAT_X318);
 924         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 925 }
 926
 927 /*
 928  * Print the component list from the IPL report
 929  */
 930 static void __init log_component_list(void)
 931 {
 932         struct ipl_rb_component_entry *ptr, *end;
 933         char *str;
 934
 935         if (!early_ipl_comp_list_addr)
 936                 return;
 937         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 938                 pr_info("Linux is running with Secure-IPL enabled\n");
 939         else
 940                 pr_info("Linux is running with Secure-IPL disabled\n");
 941         ptr = (void *) early_ipl_comp_list_addr;
 942         end = (void *) ptr + early_ipl_comp_list_size;
 943         pr_info("The IPL report contains the following components:\n");
 944         while (ptr < end) {
 945                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 946                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 947                                 str = "signed, verified";
 948                         else
 949                                 str = "signed, verification failed";
 950                 } else {
 951                         str = "not signed";
 952                 }
 953                 pr_info("%016llx - %016llx (%s)\n",
 954                         ptr->addr, ptr->addr + ptr->len, str);
 955                 ptr++;
 956         }
 957 }
 958
 959 /*
 960  * Setup function called from init/main.c just after the banner
 961  * was printed.
 962  */
 963
 964 void __init setup_arch(char **cmdline_p)
 965 {
 966         /*
 967          * print what head.S has found out about the machine
 968          */
 969         if (MACHINE_IS_VM)
 970                 pr_info("Linux is running as a z/VM "
 971                         "guest operating system in 64-bit mode\n");
 972         else if (MACHINE_IS_KVM)
 973                 pr_info("Linux is running under KVM in 64-bit mode\n");
 974         else if (MACHINE_IS_LPAR)
 975                 pr_info("Linux is running natively in 64-bit mode\n");
 976         else
 977                 pr_info("Linux is running as a guest in 64-bit mode\n");
 978
 979         log_component_list();
 980
 981         /* Have one command line that is parsed and saved in /proc/cmdline */
 982         /* boot_command_line has been already set up in early.c */
 983         *cmdline_p = boot_command_line;
 984
 985         ROOT_DEV = Root_RAM0;
 986
 987         setup_initial_init_mm(_text, _etext, _edata, _end);
 988
 989         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 990                 nospec_auto_detect();
 991
 992         jump_label_init();
 993         parse_early_param();
 994 #ifdef CONFIG_CRASH_DUMP
 995         /* Deactivate elfcorehdr= kernel parameter */
 996         elfcorehdr_addr = ELFCORE_ADDR_MAX;
 997 #endif
 998
 999         os_info_init();
1000         setup_ipl();
1001         setup_task_size();
1002         setup_control_program_code();
1003
1004         /* Do some memory reservations *before* memory is added to memblock */
1005         reserve_kernel();
1006         reserve_initrd();
1007         reserve_certificate_list();
1008         reserve_mem_detect_info();
1009         memblock_set_current_limit(ident_map_size);
1010         memblock_allow_resize();
1011
1012         /* Get information about *all* installed memory */
1013         memblock_add_mem_detect_info();
1014
1015         free_mem_detect_info();
1016         setup_memory_end();
1017         memblock_dump_all();
1018         setup_memory();
1019
1020         relocate_amode31_section();
1021         setup_cr();
1022         setup_uv();
1023         dma_contiguous_reserve(ident_map_size);
1024         vmcp_cma_reserve();
1025         if (MACHINE_HAS_EDAT2)
1026                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1027
1028         check_initrd();
1029         reserve_crashkernel();
1030 #ifdef CONFIG_CRASH_DUMP
1031         /*
1032          * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
1033          * Therefore CPU and device initialization should be done afterwards.
1034          */
1035         smp_save_dump_secondary_cpus();
1036 #endif
1037
1038         setup_resources();
1039         setup_lowcore_dat_off();
1040         smp_fill_possible_mask();
1041         cpu_detect_mhz_feature();
1042         cpu_init();
1043         numa_setup();
1044         smp_detect_cpus();
1045         topology_init_early();
1046
1047         if (test_facility(193))
1048                 static_branch_enable(&cpu_has_bear);
1049
1050         /*
1051          * Create kernel page tables and switch to virtual addressing.
1052          */
1053         paging_init();
1054         memcpy_real_init();
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 #ifdef CONFIG_CRASH_DUMP
1061         smp_save_dump_ipl_cpu();
1062 #endif
1063
1064         /* Setup default console */
1065         conmode_default();
1066         set_preferred_console();
1067
1068         apply_alternative_instructions();
1069         if (IS_ENABLED(CONFIG_EXPOLINE))
1070                 nospec_init_branches();
1071
1072         /* Setup zfcp/nvme dump support */
1073         setup_zfcpdump();
1074
1075         /* Add system specific data to the random pool */
1076         setup_randomness();
1077 }