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/bootmem.h> 38 #include <linux/root_dev.h> 39 #include <linux/console.h> 40 #include <linux/kernel_stat.h> 41 #include <linux/dma-contiguous.h> 42 #include <linux/device.h> 43 #include <linux/notifier.h> 44 #include <linux/pfn.h> 45 #include <linux/ctype.h> 46 #include <linux/reboot.h> 47 #include <linux/topology.h> 48 #include <linux/kexec.h> 49 #include <linux/crash_dump.h> 50 #include <linux/memory.h> 51 #include <linux/compat.h> 52 53 #include <asm/ipl.h> 54 #include <asm/facility.h> 55 #include <asm/smp.h> 56 #include <asm/mmu_context.h> 57 #include <asm/cpcmd.h> 58 #include <asm/lowcore.h> 59 #include <asm/nmi.h> 60 #include <asm/irq.h> 61 #include <asm/page.h> 62 #include <asm/ptrace.h> 63 #include <asm/sections.h> 64 #include <asm/ebcdic.h> 65 #include <asm/diag.h> 66 #include <asm/os_info.h> 67 #include <asm/sclp.h> 68 #include <asm/sysinfo.h> 69 #include <asm/numa.h> 70 #include <asm/alternative.h> 71 #include <asm/nospec-branch.h> 72 #include "entry.h" 73 74 /* 75 * Machine setup.. 76 */ 77 unsigned int console_mode = 0; 78 EXPORT_SYMBOL(console_mode); 79 80 unsigned int console_devno = -1; 81 EXPORT_SYMBOL(console_devno); 82 83 unsigned int console_irq = -1; 84 EXPORT_SYMBOL(console_irq); 85 86 unsigned long elf_hwcap __read_mostly = 0; 87 char elf_platform[ELF_PLATFORM_SIZE]; 88 89 unsigned long int_hwcap = 0; 90 91 int __initdata memory_end_set; 92 unsigned long __initdata memory_end; 93 unsigned long __initdata max_physmem_end; 94 95 unsigned long VMALLOC_START; 96 EXPORT_SYMBOL(VMALLOC_START); 97 98 unsigned long VMALLOC_END; 99 EXPORT_SYMBOL(VMALLOC_END); 100 101 struct page *vmemmap; 102 EXPORT_SYMBOL(vmemmap); 103 104 unsigned long MODULES_VADDR; 105 unsigned long MODULES_END; 106 107 /* An array with a pointer to the lowcore of every CPU. */ 108 struct lowcore *lowcore_ptr[NR_CPUS]; 109 EXPORT_SYMBOL(lowcore_ptr); 110 111 /* 112 * This is set up by the setup-routine at boot-time 113 * for S390 need to find out, what we have to setup 114 * using address 0x10400 ... 115 */ 116 117 #include <asm/setup.h> 118 119 /* 120 * condev= and conmode= setup parameter. 121 */ 122 123 static int __init condev_setup(char *str) 124 { 125 int vdev; 126 127 vdev = simple_strtoul(str, &str, 0); 128 if (vdev >= 0 && vdev < 65536) { 129 console_devno = vdev; 130 console_irq = -1; 131 } 132 return 1; 133 } 134 135 __setup("condev=", condev_setup); 136 137 static void __init set_preferred_console(void) 138 { 139 if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP) 140 add_preferred_console("ttyS", 0, NULL); 141 else if (CONSOLE_IS_3270) 142 add_preferred_console("tty3270", 0, NULL); 143 else if (CONSOLE_IS_VT220) 144 add_preferred_console("ttyS", 1, NULL); 145 else if (CONSOLE_IS_HVC) 146 add_preferred_console("hvc", 0, NULL); 147 } 148 149 static int __init conmode_setup(char *str) 150 { 151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE) 152 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0) 153 SET_CONSOLE_SCLP; 154 #endif 155 #if defined(CONFIG_TN3215_CONSOLE) 156 if (strncmp(str, "3215", 5) == 0) 157 SET_CONSOLE_3215; 158 #endif 159 #if defined(CONFIG_TN3270_CONSOLE) 160 if (strncmp(str, "3270", 5) == 0) 161 SET_CONSOLE_3270; 162 #endif 163 set_preferred_console(); 164 return 1; 165 } 166 167 __setup("conmode=", conmode_setup); 168 169 static void __init conmode_default(void) 170 { 171 char query_buffer[1024]; 172 char *ptr; 173 174 if (MACHINE_IS_VM) { 175 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL); 176 console_devno = simple_strtoul(query_buffer + 5, NULL, 16); 177 ptr = strstr(query_buffer, "SUBCHANNEL ="); 178 console_irq = simple_strtoul(ptr + 13, NULL, 16); 179 cpcmd("QUERY TERM", query_buffer, 1024, NULL); 180 ptr = strstr(query_buffer, "CONMODE"); 181 /* 182 * Set the conmode to 3215 so that the device recognition 183 * will set the cu_type of the console to 3215. If the 184 * conmode is 3270 and we don't set it back then both 185 * 3215 and the 3270 driver will try to access the console 186 * device (3215 as console and 3270 as normal tty). 187 */ 188 cpcmd("TERM CONMODE 3215", NULL, 0, NULL); 189 if (ptr == NULL) { 190 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE) 191 SET_CONSOLE_SCLP; 192 #endif 193 return; 194 } 195 if (strncmp(ptr + 8, "3270", 4) == 0) { 196 #if defined(CONFIG_TN3270_CONSOLE) 197 SET_CONSOLE_3270; 198 #elif defined(CONFIG_TN3215_CONSOLE) 199 SET_CONSOLE_3215; 200 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE) 201 SET_CONSOLE_SCLP; 202 #endif 203 } else if (strncmp(ptr + 8, "3215", 4) == 0) { 204 #if defined(CONFIG_TN3215_CONSOLE) 205 SET_CONSOLE_3215; 206 #elif defined(CONFIG_TN3270_CONSOLE) 207 SET_CONSOLE_3270; 208 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE) 209 SET_CONSOLE_SCLP; 210 #endif 211 } 212 } else if (MACHINE_IS_KVM) { 213 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE)) 214 SET_CONSOLE_VT220; 215 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE)) 216 SET_CONSOLE_SCLP; 217 else 218 SET_CONSOLE_HVC; 219 } else { 220 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE) 221 SET_CONSOLE_SCLP; 222 #endif 223 } 224 if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE)) 225 conswitchp = &dummy_con; 226 } 227 228 #ifdef CONFIG_CRASH_DUMP 229 static void __init setup_zfcpdump(void) 230 { 231 if (ipl_info.type != IPL_TYPE_FCP_DUMP) 232 return; 233 if (OLDMEM_BASE) 234 return; 235 strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev"); 236 console_loglevel = 2; 237 } 238 #else 239 static inline void setup_zfcpdump(void) {} 240 #endif /* CONFIG_CRASH_DUMP */ 241 242 /* 243 * Reboot, halt and power_off stubs. They just call _machine_restart, 244 * _machine_halt or _machine_power_off. 245 */ 246 247 void machine_restart(char *command) 248 { 249 if ((!in_interrupt() && !in_atomic()) || oops_in_progress) 250 /* 251 * Only unblank the console if we are called in enabled 252 * context or a bust_spinlocks cleared the way for us. 253 */ 254 console_unblank(); 255 _machine_restart(command); 256 } 257 258 void machine_halt(void) 259 { 260 if (!in_interrupt() || oops_in_progress) 261 /* 262 * Only unblank the console if we are called in enabled 263 * context or a bust_spinlocks cleared the way for us. 264 */ 265 console_unblank(); 266 _machine_halt(); 267 } 268 269 void machine_power_off(void) 270 { 271 if (!in_interrupt() || oops_in_progress) 272 /* 273 * Only unblank the console if we are called in enabled 274 * context or a bust_spinlocks cleared the way for us. 275 */ 276 console_unblank(); 277 _machine_power_off(); 278 } 279 280 /* 281 * Dummy power off function. 282 */ 283 void (*pm_power_off)(void) = machine_power_off; 284 EXPORT_SYMBOL_GPL(pm_power_off); 285 286 static int __init early_parse_mem(char *p) 287 { 288 memory_end = memparse(p, &p); 289 memory_end &= PAGE_MASK; 290 memory_end_set = 1; 291 return 0; 292 } 293 early_param("mem", early_parse_mem); 294 295 static int __init parse_vmalloc(char *arg) 296 { 297 if (!arg) 298 return -EINVAL; 299 VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK; 300 return 0; 301 } 302 early_param("vmalloc", parse_vmalloc); 303 304 void *restart_stack __section(.data); 305 306 static void __init setup_lowcore(void) 307 { 308 struct lowcore *lc; 309 310 /* 311 * Setup lowcore for boot cpu 312 */ 313 BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE); 314 lc = memblock_virt_alloc_low(sizeof(*lc), sizeof(*lc)); 315 lc->restart_psw.mask = PSW_KERNEL_BITS; 316 lc->restart_psw.addr = (unsigned long) restart_int_handler; 317 lc->external_new_psw.mask = PSW_KERNEL_BITS | 318 PSW_MASK_DAT | PSW_MASK_MCHECK; 319 lc->external_new_psw.addr = (unsigned long) ext_int_handler; 320 lc->svc_new_psw.mask = PSW_KERNEL_BITS | 321 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; 322 lc->svc_new_psw.addr = (unsigned long) system_call; 323 lc->program_new_psw.mask = PSW_KERNEL_BITS | 324 PSW_MASK_DAT | PSW_MASK_MCHECK; 325 lc->program_new_psw.addr = (unsigned long) pgm_check_handler; 326 lc->mcck_new_psw.mask = PSW_KERNEL_BITS; 327 lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler; 328 lc->io_new_psw.mask = PSW_KERNEL_BITS | 329 PSW_MASK_DAT | PSW_MASK_MCHECK; 330 lc->io_new_psw.addr = (unsigned long) io_int_handler; 331 lc->clock_comparator = clock_comparator_max; 332 lc->kernel_stack = ((unsigned long) &init_thread_union) 333 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); 334 lc->async_stack = (unsigned long) 335 memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE) 336 + ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); 337 lc->panic_stack = (unsigned long) 338 memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE) 339 + PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs); 340 lc->current_task = (unsigned long)&init_task; 341 lc->lpp = LPP_MAGIC; 342 lc->machine_flags = S390_lowcore.machine_flags; 343 lc->preempt_count = S390_lowcore.preempt_count; 344 lc->stfl_fac_list = S390_lowcore.stfl_fac_list; 345 memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list, 346 sizeof(lc->stfle_fac_list)); 347 memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list, 348 sizeof(lc->alt_stfle_fac_list)); 349 nmi_alloc_boot_cpu(lc); 350 vdso_alloc_boot_cpu(lc); 351 lc->sync_enter_timer = S390_lowcore.sync_enter_timer; 352 lc->async_enter_timer = S390_lowcore.async_enter_timer; 353 lc->exit_timer = S390_lowcore.exit_timer; 354 lc->user_timer = S390_lowcore.user_timer; 355 lc->system_timer = S390_lowcore.system_timer; 356 lc->steal_timer = S390_lowcore.steal_timer; 357 lc->last_update_timer = S390_lowcore.last_update_timer; 358 lc->last_update_clock = S390_lowcore.last_update_clock; 359 360 restart_stack = memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE); 361 restart_stack += ASYNC_SIZE; 362 363 /* 364 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant 365 * restart data to the absolute zero lowcore. This is necessary if 366 * PSW restart is done on an offline CPU that has lowcore zero. 367 */ 368 lc->restart_stack = (unsigned long) restart_stack; 369 lc->restart_fn = (unsigned long) do_restart; 370 lc->restart_data = 0; 371 lc->restart_source = -1UL; 372 373 /* Setup absolute zero lowcore */ 374 mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack); 375 mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn); 376 mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data); 377 mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source); 378 mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw); 379 380 #ifdef CONFIG_SMP 381 lc->spinlock_lockval = arch_spin_lockval(0); 382 lc->spinlock_index = 0; 383 arch_spin_lock_setup(0); 384 #endif 385 lc->br_r1_trampoline = 0x07f1; /* br %r1 */ 386 387 set_prefix((u32)(unsigned long) lc); 388 lowcore_ptr[0] = lc; 389 } 390 391 static struct resource code_resource = { 392 .name = "Kernel code", 393 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 394 }; 395 396 static struct resource data_resource = { 397 .name = "Kernel data", 398 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 399 }; 400 401 static struct resource bss_resource = { 402 .name = "Kernel bss", 403 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 404 }; 405 406 static struct resource __initdata *standard_resources[] = { 407 &code_resource, 408 &data_resource, 409 &bss_resource, 410 }; 411 412 static void __init setup_resources(void) 413 { 414 struct resource *res, *std_res, *sub_res; 415 struct memblock_region *reg; 416 int j; 417 418 code_resource.start = (unsigned long) _text; 419 code_resource.end = (unsigned long) _etext - 1; 420 data_resource.start = (unsigned long) _etext; 421 data_resource.end = (unsigned long) _edata - 1; 422 bss_resource.start = (unsigned long) __bss_start; 423 bss_resource.end = (unsigned long) __bss_stop - 1; 424 425 for_each_memblock(memory, reg) { 426 res = memblock_virt_alloc(sizeof(*res), 8); 427 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM; 428 429 res->name = "System RAM"; 430 res->start = reg->base; 431 res->end = reg->base + reg->size - 1; 432 request_resource(&iomem_resource, res); 433 434 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) { 435 std_res = standard_resources[j]; 436 if (std_res->start < res->start || 437 std_res->start > res->end) 438 continue; 439 if (std_res->end > res->end) { 440 sub_res = memblock_virt_alloc(sizeof(*sub_res), 8); 441 *sub_res = *std_res; 442 sub_res->end = res->end; 443 std_res->start = res->end + 1; 444 request_resource(res, sub_res); 445 } else { 446 request_resource(res, std_res); 447 } 448 } 449 } 450 #ifdef CONFIG_CRASH_DUMP 451 /* 452 * Re-add removed crash kernel memory as reserved memory. This makes 453 * sure it will be mapped with the identity mapping and struct pages 454 * will be created, so it can be resized later on. 455 * However add it later since the crash kernel resource should not be 456 * part of the System RAM resource. 457 */ 458 if (crashk_res.end) { 459 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0); 460 memblock_reserve(crashk_res.start, resource_size(&crashk_res)); 461 insert_resource(&iomem_resource, &crashk_res); 462 } 463 #endif 464 } 465 466 static void __init setup_memory_end(void) 467 { 468 unsigned long vmax, vmalloc_size, tmp; 469 470 /* Choose kernel address space layout: 2, 3, or 4 levels. */ 471 vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN; 472 tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE; 473 tmp = tmp * (sizeof(struct page) + PAGE_SIZE); 474 if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE) 475 vmax = _REGION2_SIZE; /* 3-level kernel page table */ 476 else 477 vmax = _REGION1_SIZE; /* 4-level kernel page table */ 478 /* module area is at the end of the kernel address space. */ 479 MODULES_END = vmax; 480 MODULES_VADDR = MODULES_END - MODULES_LEN; 481 VMALLOC_END = MODULES_VADDR; 482 VMALLOC_START = vmax - vmalloc_size; 483 484 /* Split remaining virtual space between 1:1 mapping & vmemmap array */ 485 tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page)); 486 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */ 487 tmp = SECTION_ALIGN_UP(tmp); 488 tmp = VMALLOC_START - tmp * sizeof(struct page); 489 tmp &= ~((vmax >> 11) - 1); /* align to page table level */ 490 tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS); 491 vmemmap = (struct page *) tmp; 492 493 /* Take care that memory_end is set and <= vmemmap */ 494 memory_end = min(memory_end ?: max_physmem_end, tmp); 495 max_pfn = max_low_pfn = PFN_DOWN(memory_end); 496 memblock_remove(memory_end, ULONG_MAX); 497 498 pr_notice("The maximum memory size is %luMB\n", memory_end >> 20); 499 } 500 501 #ifdef CONFIG_CRASH_DUMP 502 503 /* 504 * When kdump is enabled, we have to ensure that no memory from 505 * the area [0 - crashkernel memory size] and 506 * [crashk_res.start - crashk_res.end] is set offline. 507 */ 508 static int kdump_mem_notifier(struct notifier_block *nb, 509 unsigned long action, void *data) 510 { 511 struct memory_notify *arg = data; 512 513 if (action != MEM_GOING_OFFLINE) 514 return NOTIFY_OK; 515 if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res))) 516 return NOTIFY_BAD; 517 if (arg->start_pfn > PFN_DOWN(crashk_res.end)) 518 return NOTIFY_OK; 519 if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start)) 520 return NOTIFY_OK; 521 return NOTIFY_BAD; 522 } 523 524 static struct notifier_block kdump_mem_nb = { 525 .notifier_call = kdump_mem_notifier, 526 }; 527 528 #endif 529 530 /* 531 * Make sure that the area behind memory_end is protected 532 */ 533 static void reserve_memory_end(void) 534 { 535 #ifdef CONFIG_CRASH_DUMP 536 if (ipl_info.type == IPL_TYPE_FCP_DUMP && 537 !OLDMEM_BASE && sclp.hsa_size) { 538 memory_end = sclp.hsa_size; 539 memory_end &= PAGE_MASK; 540 memory_end_set = 1; 541 } 542 #endif 543 if (!memory_end_set) 544 return; 545 memblock_reserve(memory_end, ULONG_MAX); 546 } 547 548 /* 549 * Make sure that oldmem, where the dump is stored, is protected 550 */ 551 static void reserve_oldmem(void) 552 { 553 #ifdef CONFIG_CRASH_DUMP 554 if (OLDMEM_BASE) 555 /* Forget all memory above the running kdump system */ 556 memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX); 557 #endif 558 } 559 560 /* 561 * Make sure that oldmem, where the dump is stored, is protected 562 */ 563 static void remove_oldmem(void) 564 { 565 #ifdef CONFIG_CRASH_DUMP 566 if (OLDMEM_BASE) 567 /* Forget all memory above the running kdump system */ 568 memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX); 569 #endif 570 } 571 572 /* 573 * Reserve memory for kdump kernel to be loaded with kexec 574 */ 575 static void __init reserve_crashkernel(void) 576 { 577 #ifdef CONFIG_CRASH_DUMP 578 unsigned long long crash_base, crash_size; 579 phys_addr_t low, high; 580 int rc; 581 582 rc = parse_crashkernel(boot_command_line, memory_end, &crash_size, 583 &crash_base); 584 585 crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN); 586 crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN); 587 if (rc || crash_size == 0) 588 return; 589 590 if (memblock.memory.regions[0].size < crash_size) { 591 pr_info("crashkernel reservation failed: %s\n", 592 "first memory chunk must be at least crashkernel size"); 593 return; 594 } 595 596 low = crash_base ?: OLDMEM_BASE; 597 high = low + crash_size; 598 if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) { 599 /* The crashkernel fits into OLDMEM, reuse OLDMEM */ 600 crash_base = low; 601 } else { 602 /* Find suitable area in free memory */ 603 low = max_t(unsigned long, crash_size, sclp.hsa_size); 604 high = crash_base ? crash_base + crash_size : ULONG_MAX; 605 606 if (crash_base && crash_base < low) { 607 pr_info("crashkernel reservation failed: %s\n", 608 "crash_base too low"); 609 return; 610 } 611 low = crash_base ?: low; 612 crash_base = memblock_find_in_range(low, high, crash_size, 613 KEXEC_CRASH_MEM_ALIGN); 614 } 615 616 if (!crash_base) { 617 pr_info("crashkernel reservation failed: %s\n", 618 "no suitable area found"); 619 return; 620 } 621 622 if (register_memory_notifier(&kdump_mem_nb)) 623 return; 624 625 if (!OLDMEM_BASE && MACHINE_IS_VM) 626 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size)); 627 crashk_res.start = crash_base; 628 crashk_res.end = crash_base + crash_size - 1; 629 memblock_remove(crash_base, crash_size); 630 pr_info("Reserving %lluMB of memory at %lluMB " 631 "for crashkernel (System RAM: %luMB)\n", 632 crash_size >> 20, crash_base >> 20, 633 (unsigned long)memblock.memory.total_size >> 20); 634 os_info_crashkernel_add(crash_base, crash_size); 635 #endif 636 } 637 638 /* 639 * Reserve the initrd from being used by memblock 640 */ 641 static void __init reserve_initrd(void) 642 { 643 #ifdef CONFIG_BLK_DEV_INITRD 644 if (!INITRD_START || !INITRD_SIZE) 645 return; 646 initrd_start = INITRD_START; 647 initrd_end = initrd_start + INITRD_SIZE; 648 memblock_reserve(INITRD_START, INITRD_SIZE); 649 #endif 650 } 651 652 /* 653 * Check for initrd being in usable memory 654 */ 655 static void __init check_initrd(void) 656 { 657 #ifdef CONFIG_BLK_DEV_INITRD 658 if (INITRD_START && INITRD_SIZE && 659 !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) { 660 pr_err("The initial RAM disk does not fit into the memory\n"); 661 memblock_free(INITRD_START, INITRD_SIZE); 662 initrd_start = initrd_end = 0; 663 } 664 #endif 665 } 666 667 /* 668 * Reserve memory used for lowcore/command line/kernel image. 669 */ 670 static void __init reserve_kernel(void) 671 { 672 unsigned long start_pfn = PFN_UP(__pa(_end)); 673 674 #ifdef CONFIG_DMA_API_DEBUG 675 /* 676 * DMA_API_DEBUG code stumbles over addresses from the 677 * range [_ehead, _stext]. Mark the memory as reserved 678 * so it is not used for CONFIG_DMA_API_DEBUG=y. 679 */ 680 memblock_reserve(0, PFN_PHYS(start_pfn)); 681 #else 682 memblock_reserve(0, (unsigned long)_ehead); 683 memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn) 684 - (unsigned long)_stext); 685 #endif 686 } 687 688 static void __init setup_memory(void) 689 { 690 struct memblock_region *reg; 691 692 /* 693 * Init storage key for present memory 694 */ 695 for_each_memblock(memory, reg) { 696 storage_key_init_range(reg->base, reg->base + reg->size); 697 } 698 psw_set_key(PAGE_DEFAULT_KEY); 699 700 /* Only cosmetics */ 701 memblock_enforce_memory_limit(memblock_end_of_DRAM()); 702 } 703 704 /* 705 * Setup hardware capabilities. 706 */ 707 static int __init setup_hwcaps(void) 708 { 709 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 }; 710 struct cpuid cpu_id; 711 int i; 712 713 /* 714 * The store facility list bits numbers as found in the principles 715 * of operation are numbered with bit 1UL<<31 as number 0 to 716 * bit 1UL<<0 as number 31. 717 * Bit 0: instructions named N3, "backported" to esa-mode 718 * Bit 2: z/Architecture mode is active 719 * Bit 7: the store-facility-list-extended facility is installed 720 * Bit 17: the message-security assist is installed 721 * Bit 19: the long-displacement facility is installed 722 * Bit 21: the extended-immediate facility is installed 723 * Bit 22: extended-translation facility 3 is installed 724 * Bit 30: extended-translation facility 3 enhancement facility 725 * These get translated to: 726 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1, 727 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3, 728 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and 729 * HWCAP_S390_ETF3EH bit 8 (22 && 30). 730 */ 731 for (i = 0; i < 6; i++) 732 if (test_facility(stfl_bits[i])) 733 elf_hwcap |= 1UL << i; 734 735 if (test_facility(22) && test_facility(30)) 736 elf_hwcap |= HWCAP_S390_ETF3EH; 737 738 /* 739 * Check for additional facilities with store-facility-list-extended. 740 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0 741 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information 742 * as stored by stfl, bits 32-xxx contain additional facilities. 743 * How many facility words are stored depends on the number of 744 * doublewords passed to the instruction. The additional facilities 745 * are: 746 * Bit 42: decimal floating point facility is installed 747 * Bit 44: perform floating point operation facility is installed 748 * translated to: 749 * HWCAP_S390_DFP bit 6 (42 && 44). 750 */ 751 if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44)) 752 elf_hwcap |= HWCAP_S390_DFP; 753 754 /* 755 * Huge page support HWCAP_S390_HPAGE is bit 7. 756 */ 757 if (MACHINE_HAS_EDAT1) 758 elf_hwcap |= HWCAP_S390_HPAGE; 759 760 /* 761 * 64-bit register support for 31-bit processes 762 * HWCAP_S390_HIGH_GPRS is bit 9. 763 */ 764 elf_hwcap |= HWCAP_S390_HIGH_GPRS; 765 766 /* 767 * Transactional execution support HWCAP_S390_TE is bit 10. 768 */ 769 if (MACHINE_HAS_TE) 770 elf_hwcap |= HWCAP_S390_TE; 771 772 /* 773 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension 774 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX 775 * instead of facility bit 129. 776 */ 777 if (MACHINE_HAS_VX) { 778 elf_hwcap |= HWCAP_S390_VXRS; 779 if (test_facility(134)) 780 elf_hwcap |= HWCAP_S390_VXRS_EXT; 781 if (test_facility(135)) 782 elf_hwcap |= HWCAP_S390_VXRS_BCD; 783 } 784 785 /* 786 * Guarded storage support HWCAP_S390_GS is bit 12. 787 */ 788 if (MACHINE_HAS_GS) 789 elf_hwcap |= HWCAP_S390_GS; 790 791 get_cpu_id(&cpu_id); 792 add_device_randomness(&cpu_id, sizeof(cpu_id)); 793 switch (cpu_id.machine) { 794 case 0x2064: 795 case 0x2066: 796 default: /* Use "z900" as default for 64 bit kernels. */ 797 strcpy(elf_platform, "z900"); 798 break; 799 case 0x2084: 800 case 0x2086: 801 strcpy(elf_platform, "z990"); 802 break; 803 case 0x2094: 804 case 0x2096: 805 strcpy(elf_platform, "z9-109"); 806 break; 807 case 0x2097: 808 case 0x2098: 809 strcpy(elf_platform, "z10"); 810 break; 811 case 0x2817: 812 case 0x2818: 813 strcpy(elf_platform, "z196"); 814 break; 815 case 0x2827: 816 case 0x2828: 817 strcpy(elf_platform, "zEC12"); 818 break; 819 case 0x2964: 820 case 0x2965: 821 strcpy(elf_platform, "z13"); 822 break; 823 case 0x3906: 824 case 0x3907: 825 strcpy(elf_platform, "z14"); 826 break; 827 } 828 829 /* 830 * Virtualization support HWCAP_INT_SIE is bit 0. 831 */ 832 if (sclp.has_sief2) 833 int_hwcap |= HWCAP_INT_SIE; 834 835 return 0; 836 } 837 arch_initcall(setup_hwcaps); 838 839 /* 840 * Add system information as device randomness 841 */ 842 static void __init setup_randomness(void) 843 { 844 struct sysinfo_3_2_2 *vmms; 845 846 vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE); 847 if (stsi(vmms, 3, 2, 2) == 0 && vmms->count) 848 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count); 849 memblock_free((unsigned long) vmms, PAGE_SIZE); 850 } 851 852 /* 853 * Find the correct size for the task_struct. This depends on 854 * the size of the struct fpu at the end of the thread_struct 855 * which is embedded in the task_struct. 856 */ 857 static void __init setup_task_size(void) 858 { 859 int task_size = sizeof(struct task_struct); 860 861 if (!MACHINE_HAS_VX) { 862 task_size -= sizeof(__vector128) * __NUM_VXRS; 863 task_size += sizeof(freg_t) * __NUM_FPRS; 864 } 865 arch_task_struct_size = task_size; 866 } 867 868 /* 869 * Setup function called from init/main.c just after the banner 870 * was printed. 871 */ 872 873 void __init setup_arch(char **cmdline_p) 874 { 875 /* 876 * print what head.S has found out about the machine 877 */ 878 if (MACHINE_IS_VM) 879 pr_info("Linux is running as a z/VM " 880 "guest operating system in 64-bit mode\n"); 881 else if (MACHINE_IS_KVM) 882 pr_info("Linux is running under KVM in 64-bit mode\n"); 883 else if (MACHINE_IS_LPAR) 884 pr_info("Linux is running natively in 64-bit mode\n"); 885 886 /* Have one command line that is parsed and saved in /proc/cmdline */ 887 /* boot_command_line has been already set up in early.c */ 888 *cmdline_p = boot_command_line; 889 890 ROOT_DEV = Root_RAM0; 891 892 /* Is init_mm really needed? */ 893 init_mm.start_code = PAGE_OFFSET; 894 init_mm.end_code = (unsigned long) _etext; 895 init_mm.end_data = (unsigned long) _edata; 896 init_mm.brk = (unsigned long) _end; 897 898 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO)) 899 nospec_auto_detect(); 900 901 parse_early_param(); 902 #ifdef CONFIG_CRASH_DUMP 903 /* Deactivate elfcorehdr= kernel parameter */ 904 elfcorehdr_addr = ELFCORE_ADDR_MAX; 905 #endif 906 907 os_info_init(); 908 setup_ipl(); 909 setup_task_size(); 910 911 /* Do some memory reservations *before* memory is added to memblock */ 912 reserve_memory_end(); 913 reserve_oldmem(); 914 reserve_kernel(); 915 reserve_initrd(); 916 memblock_allow_resize(); 917 918 /* Get information about *all* installed memory */ 919 detect_memory_memblock(); 920 921 remove_oldmem(); 922 923 /* 924 * Make sure all chunks are MAX_ORDER aligned so we don't need the 925 * extra checks that HOLES_IN_ZONE would require. 926 * 927 * Is this still required? 928 */ 929 memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT)); 930 931 setup_memory_end(); 932 setup_memory(); 933 dma_contiguous_reserve(memory_end); 934 vmcp_cma_reserve(); 935 936 check_initrd(); 937 reserve_crashkernel(); 938 #ifdef CONFIG_CRASH_DUMP 939 /* 940 * Be aware that smp_save_dump_cpus() triggers a system reset. 941 * Therefore CPU and device initialization should be done afterwards. 942 */ 943 smp_save_dump_cpus(); 944 #endif 945 946 setup_resources(); 947 setup_lowcore(); 948 smp_fill_possible_mask(); 949 cpu_detect_mhz_feature(); 950 cpu_init(); 951 numa_setup(); 952 smp_detect_cpus(); 953 topology_init_early(); 954 955 /* 956 * Create kernel page tables and switch to virtual addressing. 957 */ 958 paging_init(); 959 960 /* Setup default console */ 961 conmode_default(); 962 set_preferred_console(); 963 964 apply_alternative_instructions(); 965 if (IS_ENABLED(CONFIG_EXPOLINE)) 966 nospec_init_branches(); 967 968 /* Setup zfcpdump support */ 969 setup_zfcpdump(); 970 971 /* Add system specific data to the random pool */ 972 setup_randomness(); 973 } 974