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         int i;
 511
 512         __ctl_clear_bit(0, 28);
 513         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 514         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 515         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 516         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 517         __ctl_set_bit(0, 28);
 518         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 519         if (abs_lowcore_map(0, lowcore_ptr[0], true))
 520                 panic("Couldn't setup absolute lowcore");
 521         abs_lowcore_mapped = true;
 522         abs_lc = get_abs_lowcore(&flags);
 523         abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
 524         abs_lc->program_new_psw = S390_lowcore.program_new_psw;
 525         for (i = 0; i < 16; i++)
 526                 abs_lc->cregs_save_area[i] = S390_lowcore.cregs_save_area[i];
 527         put_abs_lowcore(abs_lc, flags);
 528 }
 529
 530 static struct resource code_resource = {
 531         .name  = "Kernel code",
 532         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 533 };
 534
 535 static struct resource data_resource = {
 536         .name = "Kernel data",
 537         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 538 };
 539
 540 static struct resource bss_resource = {
 541         .name = "Kernel bss",
 542         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 543 };
 544
 545 static struct resource __initdata *standard_resources[] = {
 546         &code_resource,
 547         &data_resource,
 548         &bss_resource,
 549 };
 550
 551 static void __init setup_resources(void)
 552 {
 553         struct resource *res, *std_res, *sub_res;
 554         phys_addr_t start, end;
 555         int j;
 556         u64 i;
 557
 558         code_resource.start = (unsigned long) _text;
 559         code_resource.end = (unsigned long) _etext - 1;
 560         data_resource.start = (unsigned long) _etext;
 561         data_resource.end = (unsigned long) _edata - 1;
 562         bss_resource.start = (unsigned long) __bss_start;
 563         bss_resource.end = (unsigned long) __bss_stop - 1;
 564
 565         for_each_mem_range(i, &start, &end) {
 566                 res = memblock_alloc(sizeof(*res), 8);
 567                 if (!res)
 568                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 569                               __func__, sizeof(*res), 8);
 570                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 571
 572                 res->name = "System RAM";
 573                 res->start = start;
 574                 /*
 575                  * In memblock, end points to the first byte after the
 576                  * range while in resourses, end points to the last byte in
 577                  * the range.
 578                  */
 579                 res->end = end - 1;
 580                 request_resource(&iomem_resource, res);
 581
 582                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 583                         std_res = standard_resources[j];
 584                         if (std_res->start < res->start ||
 585                             std_res->start > res->end)
 586                                 continue;
 587                         if (std_res->end > res->end) {
 588                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 589                                 if (!sub_res)
 590                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 591                                               __func__, sizeof(*sub_res), 8);
 592                                 *sub_res = *std_res;
 593                                 sub_res->end = res->end;
 594                                 std_res->start = res->end + 1;
 595                                 request_resource(res, sub_res);
 596                         } else {
 597                                 request_resource(res, std_res);
 598                         }
 599                 }
 600         }
 601 #ifdef CONFIG_CRASH_DUMP
 602         /*
 603          * Re-add removed crash kernel memory as reserved memory. This makes
 604          * sure it will be mapped with the identity mapping and struct pages
 605          * will be created, so it can be resized later on.
 606          * However add it later since the crash kernel resource should not be
 607          * part of the System RAM resource.
 608          */
 609         if (crashk_res.end) {
 610                 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 611                                   0, MEMBLOCK_NONE);
 612                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 613                 insert_resource(&iomem_resource, &crashk_res);
 614         }
 615 #endif
 616 }
 617
 618 static void __init setup_memory_end(void)
 619 {
 620         memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 621         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 622         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 623 }
 624
 625 #ifdef CONFIG_CRASH_DUMP
 626
 627 /*
 628  * When kdump is enabled, we have to ensure that no memory from the area
 629  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 630  * the crashkernel memory region when kdump is triggered. The crashkernel
 631  * memory region can never get offlined (pages are unmovable).
 632  */
 633 static int kdump_mem_notifier(struct notifier_block *nb,
 634                               unsigned long action, void *data)
 635 {
 636         struct memory_notify *arg = data;
 637
 638         if (action != MEM_GOING_OFFLINE)
 639                 return NOTIFY_OK;
 640         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 641                 return NOTIFY_BAD;
 642         return NOTIFY_OK;
 643 }
 644
 645 static struct notifier_block kdump_mem_nb = {
 646         .notifier_call = kdump_mem_notifier,
 647 };
 648
 649 #endif
 650
 651 /*
 652  * Reserve memory for kdump kernel to be loaded with kexec
 653  */
 654 static void __init reserve_crashkernel(void)
 655 {
 656 #ifdef CONFIG_CRASH_DUMP
 657         unsigned long long crash_base, crash_size;
 658         phys_addr_t low, high;
 659         int rc;
 660
 661         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 662                                &crash_base);
 663
 664         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 665         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 666         if (rc || crash_size == 0)
 667                 return;
 668
 669         if (memblock.memory.regions[0].size < crash_size) {
 670                 pr_info("crashkernel reservation failed: %s\n",
 671                         "first memory chunk must be at least crashkernel size");
 672                 return;
 673         }
 674
 675         low = crash_base ?: oldmem_data.start;
 676         high = low + crash_size;
 677         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 678                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 679                 crash_base = low;
 680         } else {
 681                 /* Find suitable area in free memory */
 682                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 683                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 684
 685                 if (crash_base && crash_base < low) {
 686                         pr_info("crashkernel reservation failed: %s\n",
 687                                 "crash_base too low");
 688                         return;
 689                 }
 690                 low = crash_base ?: low;
 691                 crash_base = memblock_phys_alloc_range(crash_size,
 692                                                        KEXEC_CRASH_MEM_ALIGN,
 693                                                        low, high);
 694         }
 695
 696         if (!crash_base) {
 697                 pr_info("crashkernel reservation failed: %s\n",
 698                         "no suitable area found");
 699                 return;
 700         }
 701
 702         if (register_memory_notifier(&kdump_mem_nb)) {
 703                 memblock_phys_free(crash_base, crash_size);
 704                 return;
 705         }
 706
 707         if (!oldmem_data.start && MACHINE_IS_VM)
 708                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 709         crashk_res.start = crash_base;
 710         crashk_res.end = crash_base + crash_size - 1;
 711         memblock_remove(crash_base, crash_size);
 712         pr_info("Reserving %lluMB of memory at %lluMB "
 713                 "for crashkernel (System RAM: %luMB)\n",
 714                 crash_size >> 20, crash_base >> 20,
 715                 (unsigned long)memblock.memory.total_size >> 20);
 716         os_info_crashkernel_add(crash_base, crash_size);
 717 #endif
 718 }
 719
 720 /*
 721  * Reserve the initrd from being used by memblock
 722  */
 723 static void __init reserve_initrd(void)
 724 {
 725 #ifdef CONFIG_BLK_DEV_INITRD
 726         if (!initrd_data.start || !initrd_data.size)
 727                 return;
 728         initrd_start = (unsigned long)__va(initrd_data.start);
 729         initrd_end = initrd_start + initrd_data.size;
 730         memblock_reserve(initrd_data.start, initrd_data.size);
 731 #endif
 732 }
 733
 734 /*
 735  * Reserve the memory area used to pass the certificate lists
 736  */
 737 static void __init reserve_certificate_list(void)
 738 {
 739         if (ipl_cert_list_addr)
 740                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 741 }
 742
 743 static void __init reserve_mem_detect_info(void)
 744 {
 745         unsigned long start, size;
 746
 747         get_mem_detect_reserved(&start, &size);
 748         if (size)
 749                 memblock_reserve(start, size);
 750 }
 751
 752 static void __init free_mem_detect_info(void)
 753 {
 754         unsigned long start, size;
 755
 756         get_mem_detect_reserved(&start, &size);
 757         if (size)
 758                 memblock_phys_free(start, size);
 759 }
 760
 761 static const char * __init get_mem_info_source(void)
 762 {
 763         switch (mem_detect.info_source) {
 764         case MEM_DETECT_SCLP_STOR_INFO:
 765                 return "sclp storage info";
 766         case MEM_DETECT_DIAG260:
 767                 return "diag260";
 768         case MEM_DETECT_SCLP_READ_INFO:
 769                 return "sclp read info";
 770         case MEM_DETECT_BIN_SEARCH:
 771                 return "binary search";
 772         }
 773         return "none";
 774 }
 775
 776 static void __init memblock_add_mem_detect_info(void)
 777 {
 778         unsigned long start, end;
 779         int i;
 780
 781         pr_debug("physmem info source: %s (%hhd)\n",
 782                  get_mem_info_source(), mem_detect.info_source);
 783         /* keep memblock lists close to the kernel */
 784         memblock_set_bottom_up(true);
 785         for_each_mem_detect_block(i, &start, &end) {
 786                 memblock_add(start, end - start);
 787                 memblock_physmem_add(start, end - start);
 788         }
 789         memblock_set_bottom_up(false);
 790         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 791 }
 792
 793 /*
 794  * Check for initrd being in usable memory
 795  */
 796 static void __init check_initrd(void)
 797 {
 798 #ifdef CONFIG_BLK_DEV_INITRD
 799         if (initrd_data.start && initrd_data.size &&
 800             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 801                 pr_err("The initial RAM disk does not fit into the memory\n");
 802                 memblock_phys_free(initrd_data.start, initrd_data.size);
 803                 initrd_start = initrd_end = 0;
 804         }
 805 #endif
 806 }
 807
 808 /*
 809  * Reserve memory used for lowcore/command line/kernel image.
 810  */
 811 static void __init reserve_kernel(void)
 812 {
 813         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 814         memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 815         memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 816         memblock_reserve(__amode31_base, __eamode31 - __samode31);
 817         memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 818         memblock_reserve(__pa(_stext), _end - _stext);
 819 }
 820
 821 static void __init setup_memory(void)
 822 {
 823         phys_addr_t start, end;
 824         u64 i;
 825
 826         /*
 827          * Init storage key for present memory
 828          */
 829         for_each_mem_range(i, &start, &end)
 830                 storage_key_init_range(start, end);
 831
 832         psw_set_key(PAGE_DEFAULT_KEY);
 833 }
 834
 835 static void __init relocate_amode31_section(void)
 836 {
 837         unsigned long amode31_size = __eamode31 - __samode31;
 838         long amode31_offset = __amode31_base - __samode31;
 839         long *ptr;
 840
 841         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 842
 843         /* Move original AMODE31 section to the new one */
 844         memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 845         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 846         memset((void *)__samode31, 0, amode31_size);
 847
 848         /* Update all AMODE31 region references */
 849         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 850                 *ptr += amode31_offset;
 851 }
 852
 853 /* This must be called after AMODE31 relocation */
 854 static void __init setup_cr(void)
 855 {
 856         union ctlreg2 cr2;
 857         union ctlreg5 cr5;
 858         union ctlreg15 cr15;
 859
 860         __ctl_duct[1] = (unsigned long)__ctl_aste;
 861         __ctl_duct[2] = (unsigned long)__ctl_aste;
 862         __ctl_duct[4] = (unsigned long)__ctl_duald;
 863
 864         /* Update control registers CR2, CR5 and CR15 */
 865         __ctl_store(cr2.val, 2, 2);
 866         __ctl_store(cr5.val, 5, 5);
 867         __ctl_store(cr15.val, 15, 15);
 868         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 869         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 870         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 871         __ctl_load(cr2.val, 2, 2);
 872         __ctl_load(cr5.val, 5, 5);
 873         __ctl_load(cr15.val, 15, 15);
 874 }
 875
 876 /*
 877  * Add system information as device randomness
 878  */
 879 static void __init setup_randomness(void)
 880 {
 881         struct sysinfo_3_2_2 *vmms;
 882
 883         vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 884         if (!vmms)
 885                 panic("Failed to allocate memory for sysinfo structure\n");
 886         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 887                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 888         memblock_free(vmms, PAGE_SIZE);
 889
 890         if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
 891                 static_branch_enable(&s390_arch_random_available);
 892 }
 893
 894 /*
 895  * Find the correct size for the task_struct. This depends on
 896  * the size of the struct fpu at the end of the thread_struct
 897  * which is embedded in the task_struct.
 898  */
 899 static void __init setup_task_size(void)
 900 {
 901         int task_size = sizeof(struct task_struct);
 902
 903         if (!MACHINE_HAS_VX) {
 904                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 905                 task_size += sizeof(freg_t) * __NUM_FPRS;
 906         }
 907         arch_task_struct_size = task_size;
 908 }
 909
 910 /*
 911  * Issue diagnose 318 to set the control program name and
 912  * version codes.
 913  */
 914 static void __init setup_control_program_code(void)
 915 {
 916         union diag318_info diag318_info = {
 917                 .cpnc = CPNC_LINUX,
 918                 .cpvc = 0,
 919         };
 920
 921         if (!sclp.has_diag318)
 922                 return;
 923
 924         diag_stat_inc(DIAG_STAT_X318);
 925         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 926 }
 927
 928 /*
 929  * Print the component list from the IPL report
 930  */
 931 static void __init log_component_list(void)
 932 {
 933         struct ipl_rb_component_entry *ptr, *end;
 934         char *str;
 935
 936         if (!early_ipl_comp_list_addr)
 937                 return;
 938         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 939                 pr_info("Linux is running with Secure-IPL enabled\n");
 940         else
 941                 pr_info("Linux is running with Secure-IPL disabled\n");
 942         ptr = (void *) early_ipl_comp_list_addr;
 943         end = (void *) ptr + early_ipl_comp_list_size;
 944         pr_info("The IPL report contains the following components:\n");
 945         while (ptr < end) {
 946                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 947                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 948                                 str = "signed, verified";
 949                         else
 950                                 str = "signed, verification failed";
 951                 } else {
 952                         str = "not signed";
 953                 }
 954                 pr_info("%016llx - %016llx (%s)\n",
 955                         ptr->addr, ptr->addr + ptr->len, str);
 956                 ptr++;
 957         }
 958 }
 959
 960 /*
 961  * Setup function called from init/main.c just after the banner
 962  * was printed.
 963  */
 964
 965 void __init setup_arch(char **cmdline_p)
 966 {
 967         /*
 968          * print what head.S has found out about the machine
 969          */
 970         if (MACHINE_IS_VM)
 971                 pr_info("Linux is running as a z/VM "
 972                         "guest operating system in 64-bit mode\n");
 973         else if (MACHINE_IS_KVM)
 974                 pr_info("Linux is running under KVM in 64-bit mode\n");
 975         else if (MACHINE_IS_LPAR)
 976                 pr_info("Linux is running natively in 64-bit mode\n");
 977         else
 978                 pr_info("Linux is running as a guest in 64-bit mode\n");
 979
 980         log_component_list();
 981
 982         /* Have one command line that is parsed and saved in /proc/cmdline */
 983         /* boot_command_line has been already set up in early.c */
 984         *cmdline_p = boot_command_line;
 985
 986         ROOT_DEV = Root_RAM0;
 987
 988         setup_initial_init_mm(_text, _etext, _edata, _end);
 989
 990         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 991                 nospec_auto_detect();
 992
 993         jump_label_init();
 994         parse_early_param();
 995 #ifdef CONFIG_CRASH_DUMP
 996         /* Deactivate elfcorehdr= kernel parameter */
 997         elfcorehdr_addr = ELFCORE_ADDR_MAX;
 998 #endif
 999
1000         os_info_init();
1001         setup_ipl();
1002         setup_task_size();
1003         setup_control_program_code();
1004
1005         /* Do some memory reservations *before* memory is added to memblock */
1006         reserve_kernel();
1007         reserve_initrd();
1008         reserve_certificate_list();
1009         reserve_mem_detect_info();
1010         memblock_set_current_limit(ident_map_size);
1011         memblock_allow_resize();
1012
1013         /* Get information about *all* installed memory */
1014         memblock_add_mem_detect_info();
1015
1016         free_mem_detect_info();
1017         setup_memory_end();
1018         memblock_dump_all();
1019         setup_memory();
1020
1021         relocate_amode31_section();
1022         setup_cr();
1023         setup_uv();
1024         dma_contiguous_reserve(ident_map_size);
1025         vmcp_cma_reserve();
1026         if (MACHINE_HAS_EDAT2)
1027                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1028
1029         check_initrd();
1030         reserve_crashkernel();
1031 #ifdef CONFIG_CRASH_DUMP
1032         /*
1033          * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
1034          * Therefore CPU and device initialization should be done afterwards.
1035          */
1036         smp_save_dump_secondary_cpus();
1037 #endif
1038
1039         setup_resources();
1040         setup_lowcore_dat_off();
1041         smp_fill_possible_mask();
1042         cpu_detect_mhz_feature();
1043         cpu_init();
1044         numa_setup();
1045         smp_detect_cpus();
1046         topology_init_early();
1047
1048         if (test_facility(193))
1049                 static_branch_enable(&cpu_has_bear);
1050
1051         /*
1052          * Create kernel page tables and switch to virtual addressing.
1053          */
1054         paging_init();
1055         memcpy_real_init();
1056         /*
1057          * After paging_init created the kernel page table, the new PSWs
1058          * in lowcore can now run with DAT enabled.
1059          */
1060         setup_lowcore_dat_on();
1061 #ifdef CONFIG_CRASH_DUMP
1062         smp_save_dump_ipl_cpu();
1063 #endif
1064
1065         /* Setup default console */
1066         conmode_default();
1067         set_preferred_console();
1068
1069         apply_alternative_instructions();
1070         if (IS_ENABLED(CONFIG_EXPOLINE))
1071                 nospec_init_branches();
1072
1073         /* Setup zfcp/nvme dump support */
1074         setup_zfcpdump();
1075
1076         /* Add system specific data to the random pool */
1077         setup_randomness();
1078 }