1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright IBM Corp. 1999, 2012
5 * Author(s): Hartmut Penner (hp@de.ibm.com),
6 * Martin Schwidefsky (schwidefsky@de.ibm.com)
8 * Derived from "arch/i386/kernel/setup.c"
9 * Copyright (C) 1995, Linus Torvalds
13 * This file handles the architecture-dependent parts of initialization
16 #define KMSG_COMPONENT "setup"
17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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>
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>
54 #include <asm/facility.h>
56 #include <asm/mmu_context.h>
57 #include <asm/cpcmd.h>
58 #include <asm/lowcore.h>
62 #include <asm/ptrace.h>
63 #include <asm/sections.h>
64 #include <asm/ebcdic.h>
66 #include <asm/os_info.h>
68 #include <asm/sysinfo.h>
70 #include <asm/alternative.h>
71 #include <asm/nospec-branch.h>
77 unsigned int console_mode = 0;
78 EXPORT_SYMBOL(console_mode);
80 unsigned int console_devno = -1;
81 EXPORT_SYMBOL(console_devno);
83 unsigned int console_irq = -1;
84 EXPORT_SYMBOL(console_irq);
86 unsigned long elf_hwcap __read_mostly = 0;
87 char elf_platform[ELF_PLATFORM_SIZE];
89 unsigned long int_hwcap = 0;
91 int __initdata memory_end_set;
92 unsigned long __initdata memory_end;
93 unsigned long __initdata max_physmem_end;
95 unsigned long VMALLOC_START;
96 EXPORT_SYMBOL(VMALLOC_START);
98 unsigned long VMALLOC_END;
99 EXPORT_SYMBOL(VMALLOC_END);
101 struct page *vmemmap;
102 EXPORT_SYMBOL(vmemmap);
104 unsigned long MODULES_VADDR;
105 unsigned long MODULES_END;
107 /* An array with a pointer to the lowcore of every CPU. */
108 struct lowcore *lowcore_ptr[NR_CPUS];
109 EXPORT_SYMBOL(lowcore_ptr);
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 ...
117 #include <asm/setup.h>
120 * condev= and conmode= setup parameter.
123 static int __init condev_setup(char *str)
127 vdev = simple_strtoul(str, &str, 0);
128 if (vdev >= 0 && vdev < 65536) {
129 console_devno = vdev;
135 __setup("condev=", condev_setup);
137 static void __init set_preferred_console(void)
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("ttysclp", 0, NULL);
145 else if (CONSOLE_IS_HVC)
146 add_preferred_console("hvc", 0, NULL);
149 static int __init conmode_setup(char *str)
151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
152 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
155 #if defined(CONFIG_TN3215_CONSOLE)
156 if (strncmp(str, "3215", 5) == 0)
159 #if defined(CONFIG_TN3270_CONSOLE)
160 if (strncmp(str, "3270", 5) == 0)
163 set_preferred_console();
167 __setup("conmode=", conmode_setup);
169 static void __init conmode_default(void)
171 char query_buffer[1024];
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");
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).
188 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
190 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
195 if (strncmp(ptr + 8, "3270", 4) == 0) {
196 #if defined(CONFIG_TN3270_CONSOLE)
198 #elif defined(CONFIG_TN3215_CONSOLE)
200 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
203 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
204 #if defined(CONFIG_TN3215_CONSOLE)
206 #elif defined(CONFIG_TN3270_CONSOLE)
208 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
212 } else if (MACHINE_IS_KVM) {
213 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
215 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
220 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
224 if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
225 conswitchp = &dummy_con;
228 #ifdef CONFIG_CRASH_DUMP
229 static void __init setup_zfcpdump(void)
231 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
235 strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
236 console_loglevel = 2;
239 static inline void setup_zfcpdump(void) {}
240 #endif /* CONFIG_CRASH_DUMP */
243 * Reboot, halt and power_off stubs. They just call _machine_restart,
244 * _machine_halt or _machine_power_off.
247 void machine_restart(char *command)
249 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
251 * Only unblank the console if we are called in enabled
252 * context or a bust_spinlocks cleared the way for us.
255 _machine_restart(command);
258 void machine_halt(void)
260 if (!in_interrupt() || oops_in_progress)
262 * Only unblank the console if we are called in enabled
263 * context or a bust_spinlocks cleared the way for us.
269 void machine_power_off(void)
271 if (!in_interrupt() || oops_in_progress)
273 * Only unblank the console if we are called in enabled
274 * context or a bust_spinlocks cleared the way for us.
277 _machine_power_off();
281 * Dummy power off function.
283 void (*pm_power_off)(void) = machine_power_off;
284 EXPORT_SYMBOL_GPL(pm_power_off);
286 static int __init early_parse_mem(char *p)
288 memory_end = memparse(p, &p);
289 memory_end &= PAGE_MASK;
293 early_param("mem", early_parse_mem);
295 static int __init parse_vmalloc(char *arg)
299 VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
302 early_param("vmalloc", parse_vmalloc);
304 void *restart_stack __section(.data);
306 static void __init setup_lowcore_dat_off(void)
311 * Setup lowcore for boot cpu
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 | PSW_MASK_MCHECK;
318 lc->external_new_psw.addr = (unsigned long) ext_int_handler;
319 lc->svc_new_psw.mask = PSW_KERNEL_BITS |
320 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
321 lc->svc_new_psw.addr = (unsigned long) system_call;
322 lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
323 lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
324 lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
325 lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
326 lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
327 lc->io_new_psw.addr = (unsigned long) io_int_handler;
328 lc->clock_comparator = clock_comparator_max;
329 lc->kernel_stack = ((unsigned long) &init_thread_union)
330 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
331 lc->async_stack = (unsigned long)
332 memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE)
333 + ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
334 lc->panic_stack = (unsigned long)
335 memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE)
336 + PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
337 lc->current_task = (unsigned long)&init_task;
339 lc->machine_flags = S390_lowcore.machine_flags;
340 lc->preempt_count = S390_lowcore.preempt_count;
341 lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
342 memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
343 sizeof(lc->stfle_fac_list));
344 memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
345 sizeof(lc->alt_stfle_fac_list));
346 nmi_alloc_boot_cpu(lc);
347 vdso_alloc_boot_cpu(lc);
348 lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
349 lc->async_enter_timer = S390_lowcore.async_enter_timer;
350 lc->exit_timer = S390_lowcore.exit_timer;
351 lc->user_timer = S390_lowcore.user_timer;
352 lc->system_timer = S390_lowcore.system_timer;
353 lc->steal_timer = S390_lowcore.steal_timer;
354 lc->last_update_timer = S390_lowcore.last_update_timer;
355 lc->last_update_clock = S390_lowcore.last_update_clock;
357 restart_stack = memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE);
358 restart_stack += ASYNC_SIZE;
361 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
362 * restart data to the absolute zero lowcore. This is necessary if
363 * PSW restart is done on an offline CPU that has lowcore zero.
365 lc->restart_stack = (unsigned long) restart_stack;
366 lc->restart_fn = (unsigned long) do_restart;
367 lc->restart_data = 0;
368 lc->restart_source = -1UL;
370 /* Setup absolute zero lowcore */
371 mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
372 mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
373 mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
374 mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
375 mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
378 lc->spinlock_lockval = arch_spin_lockval(0);
379 lc->spinlock_index = 0;
380 arch_spin_lock_setup(0);
382 lc->br_r1_trampoline = 0x07f1; /* br %r1 */
384 set_prefix((u32)(unsigned long) lc);
388 static void __init setup_lowcore_dat_on(void)
390 __ctl_clear_bit(0, 28);
391 S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
392 S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
393 S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
394 S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
395 __ctl_set_bit(0, 28);
398 static struct resource code_resource = {
399 .name = "Kernel code",
400 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
403 static struct resource data_resource = {
404 .name = "Kernel data",
405 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
408 static struct resource bss_resource = {
409 .name = "Kernel bss",
410 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
413 static struct resource __initdata *standard_resources[] = {
419 static void __init setup_resources(void)
421 struct resource *res, *std_res, *sub_res;
422 struct memblock_region *reg;
425 code_resource.start = (unsigned long) _text;
426 code_resource.end = (unsigned long) _etext - 1;
427 data_resource.start = (unsigned long) _etext;
428 data_resource.end = (unsigned long) _edata - 1;
429 bss_resource.start = (unsigned long) __bss_start;
430 bss_resource.end = (unsigned long) __bss_stop - 1;
432 for_each_memblock(memory, reg) {
433 res = memblock_virt_alloc(sizeof(*res), 8);
434 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
436 res->name = "System RAM";
437 res->start = reg->base;
438 res->end = reg->base + reg->size - 1;
439 request_resource(&iomem_resource, res);
441 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
442 std_res = standard_resources[j];
443 if (std_res->start < res->start ||
444 std_res->start > res->end)
446 if (std_res->end > res->end) {
447 sub_res = memblock_virt_alloc(sizeof(*sub_res), 8);
449 sub_res->end = res->end;
450 std_res->start = res->end + 1;
451 request_resource(res, sub_res);
453 request_resource(res, std_res);
457 #ifdef CONFIG_CRASH_DUMP
459 * Re-add removed crash kernel memory as reserved memory. This makes
460 * sure it will be mapped with the identity mapping and struct pages
461 * will be created, so it can be resized later on.
462 * However add it later since the crash kernel resource should not be
463 * part of the System RAM resource.
465 if (crashk_res.end) {
466 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
467 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
468 insert_resource(&iomem_resource, &crashk_res);
473 static void __init setup_memory_end(void)
475 unsigned long vmax, vmalloc_size, tmp;
477 /* Choose kernel address space layout: 2, 3, or 4 levels. */
478 vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
479 tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
480 tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
481 if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
482 vmax = _REGION2_SIZE; /* 3-level kernel page table */
484 vmax = _REGION1_SIZE; /* 4-level kernel page table */
485 /* module area is at the end of the kernel address space. */
487 MODULES_VADDR = MODULES_END - MODULES_LEN;
488 VMALLOC_END = MODULES_VADDR;
489 VMALLOC_START = vmax - vmalloc_size;
491 /* Split remaining virtual space between 1:1 mapping & vmemmap array */
492 tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
493 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
494 tmp = SECTION_ALIGN_UP(tmp);
495 tmp = VMALLOC_START - tmp * sizeof(struct page);
496 tmp &= ~((vmax >> 11) - 1); /* align to page table level */
497 tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
498 vmemmap = (struct page *) tmp;
500 /* Take care that memory_end is set and <= vmemmap */
501 memory_end = min(memory_end ?: max_physmem_end, tmp);
502 max_pfn = max_low_pfn = PFN_DOWN(memory_end);
503 memblock_remove(memory_end, ULONG_MAX);
505 pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
508 #ifdef CONFIG_CRASH_DUMP
511 * When kdump is enabled, we have to ensure that no memory from
512 * the area [0 - crashkernel memory size] and
513 * [crashk_res.start - crashk_res.end] is set offline.
515 static int kdump_mem_notifier(struct notifier_block *nb,
516 unsigned long action, void *data)
518 struct memory_notify *arg = data;
520 if (action != MEM_GOING_OFFLINE)
522 if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
524 if (arg->start_pfn > PFN_DOWN(crashk_res.end))
526 if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
531 static struct notifier_block kdump_mem_nb = {
532 .notifier_call = kdump_mem_notifier,
538 * Make sure that the area behind memory_end is protected
540 static void __init reserve_memory_end(void)
542 #ifdef CONFIG_CRASH_DUMP
543 if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
544 !OLDMEM_BASE && sclp.hsa_size) {
545 memory_end = sclp.hsa_size;
546 memory_end &= PAGE_MASK;
552 memblock_reserve(memory_end, ULONG_MAX);
556 * Make sure that oldmem, where the dump is stored, is protected
558 static void __init reserve_oldmem(void)
560 #ifdef CONFIG_CRASH_DUMP
562 /* Forget all memory above the running kdump system */
563 memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
568 * Make sure that oldmem, where the dump is stored, is protected
570 static void __init remove_oldmem(void)
572 #ifdef CONFIG_CRASH_DUMP
574 /* Forget all memory above the running kdump system */
575 memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
580 * Reserve memory for kdump kernel to be loaded with kexec
582 static void __init reserve_crashkernel(void)
584 #ifdef CONFIG_CRASH_DUMP
585 unsigned long long crash_base, crash_size;
586 phys_addr_t low, high;
589 rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
592 crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
593 crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
594 if (rc || crash_size == 0)
597 if (memblock.memory.regions[0].size < crash_size) {
598 pr_info("crashkernel reservation failed: %s\n",
599 "first memory chunk must be at least crashkernel size");
603 low = crash_base ?: OLDMEM_BASE;
604 high = low + crash_size;
605 if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
606 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
609 /* Find suitable area in free memory */
610 low = max_t(unsigned long, crash_size, sclp.hsa_size);
611 high = crash_base ? crash_base + crash_size : ULONG_MAX;
613 if (crash_base && crash_base < low) {
614 pr_info("crashkernel reservation failed: %s\n",
615 "crash_base too low");
618 low = crash_base ?: low;
619 crash_base = memblock_find_in_range(low, high, crash_size,
620 KEXEC_CRASH_MEM_ALIGN);
624 pr_info("crashkernel reservation failed: %s\n",
625 "no suitable area found");
629 if (register_memory_notifier(&kdump_mem_nb))
632 if (!OLDMEM_BASE && MACHINE_IS_VM)
633 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
634 crashk_res.start = crash_base;
635 crashk_res.end = crash_base + crash_size - 1;
636 memblock_remove(crash_base, crash_size);
637 pr_info("Reserving %lluMB of memory at %lluMB "
638 "for crashkernel (System RAM: %luMB)\n",
639 crash_size >> 20, crash_base >> 20,
640 (unsigned long)memblock.memory.total_size >> 20);
641 os_info_crashkernel_add(crash_base, crash_size);
646 * Reserve the initrd from being used by memblock
648 static void __init reserve_initrd(void)
650 #ifdef CONFIG_BLK_DEV_INITRD
651 if (!INITRD_START || !INITRD_SIZE)
653 initrd_start = INITRD_START;
654 initrd_end = initrd_start + INITRD_SIZE;
655 memblock_reserve(INITRD_START, INITRD_SIZE);
660 * Check for initrd being in usable memory
662 static void __init check_initrd(void)
664 #ifdef CONFIG_BLK_DEV_INITRD
665 if (INITRD_START && INITRD_SIZE &&
666 !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
667 pr_err("The initial RAM disk does not fit into the memory\n");
668 memblock_free(INITRD_START, INITRD_SIZE);
669 initrd_start = initrd_end = 0;
675 * Reserve memory used for lowcore/command line/kernel image.
677 static void __init reserve_kernel(void)
679 unsigned long start_pfn = PFN_UP(__pa(_end));
681 #ifdef CONFIG_DMA_API_DEBUG
683 * DMA_API_DEBUG code stumbles over addresses from the
684 * range [PARMAREA_END, _stext]. Mark the memory as reserved
685 * so it is not used for CONFIG_DMA_API_DEBUG=y.
687 memblock_reserve(0, PFN_PHYS(start_pfn));
689 memblock_reserve(0, PARMAREA_END);
690 memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
691 - (unsigned long)_stext);
695 static void __init setup_memory(void)
697 struct memblock_region *reg;
700 * Init storage key for present memory
702 for_each_memblock(memory, reg) {
703 storage_key_init_range(reg->base, reg->base + reg->size);
705 psw_set_key(PAGE_DEFAULT_KEY);
709 * Setup hardware capabilities.
711 static int __init setup_hwcaps(void)
713 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
718 * The store facility list bits numbers as found in the principles
719 * of operation are numbered with bit 1UL<<31 as number 0 to
720 * bit 1UL<<0 as number 31.
721 * Bit 0: instructions named N3, "backported" to esa-mode
722 * Bit 2: z/Architecture mode is active
723 * Bit 7: the store-facility-list-extended facility is installed
724 * Bit 17: the message-security assist is installed
725 * Bit 19: the long-displacement facility is installed
726 * Bit 21: the extended-immediate facility is installed
727 * Bit 22: extended-translation facility 3 is installed
728 * Bit 30: extended-translation facility 3 enhancement facility
729 * These get translated to:
730 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
731 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
732 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
733 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
735 for (i = 0; i < 6; i++)
736 if (test_facility(stfl_bits[i]))
737 elf_hwcap |= 1UL << i;
739 if (test_facility(22) && test_facility(30))
740 elf_hwcap |= HWCAP_S390_ETF3EH;
743 * Check for additional facilities with store-facility-list-extended.
744 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
745 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
746 * as stored by stfl, bits 32-xxx contain additional facilities.
747 * How many facility words are stored depends on the number of
748 * doublewords passed to the instruction. The additional facilities
750 * Bit 42: decimal floating point facility is installed
751 * Bit 44: perform floating point operation facility is installed
753 * HWCAP_S390_DFP bit 6 (42 && 44).
755 if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
756 elf_hwcap |= HWCAP_S390_DFP;
759 * Huge page support HWCAP_S390_HPAGE is bit 7.
761 if (MACHINE_HAS_EDAT1)
762 elf_hwcap |= HWCAP_S390_HPAGE;
765 * 64-bit register support for 31-bit processes
766 * HWCAP_S390_HIGH_GPRS is bit 9.
768 elf_hwcap |= HWCAP_S390_HIGH_GPRS;
771 * Transactional execution support HWCAP_S390_TE is bit 10.
774 elf_hwcap |= HWCAP_S390_TE;
777 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
778 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
779 * instead of facility bit 129.
781 if (MACHINE_HAS_VX) {
782 elf_hwcap |= HWCAP_S390_VXRS;
783 if (test_facility(134))
784 elf_hwcap |= HWCAP_S390_VXRS_EXT;
785 if (test_facility(135))
786 elf_hwcap |= HWCAP_S390_VXRS_BCD;
790 * Guarded storage support HWCAP_S390_GS is bit 12.
793 elf_hwcap |= HWCAP_S390_GS;
796 add_device_randomness(&cpu_id, sizeof(cpu_id));
797 switch (cpu_id.machine) {
800 default: /* Use "z900" as default for 64 bit kernels. */
801 strcpy(elf_platform, "z900");
805 strcpy(elf_platform, "z990");
809 strcpy(elf_platform, "z9-109");
813 strcpy(elf_platform, "z10");
817 strcpy(elf_platform, "z196");
821 strcpy(elf_platform, "zEC12");
825 strcpy(elf_platform, "z13");
829 strcpy(elf_platform, "z14");
834 * Virtualization support HWCAP_INT_SIE is bit 0.
837 int_hwcap |= HWCAP_INT_SIE;
841 arch_initcall(setup_hwcaps);
844 * Add system information as device randomness
846 static void __init setup_randomness(void)
848 struct sysinfo_3_2_2 *vmms;
850 vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE);
851 if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
852 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
853 memblock_free((unsigned long) vmms, PAGE_SIZE);
855 #ifdef CONFIG_ARCH_RANDOM
856 if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
857 static_branch_enable(&s390_arch_random_available);
862 * Find the correct size for the task_struct. This depends on
863 * the size of the struct fpu at the end of the thread_struct
864 * which is embedded in the task_struct.
866 static void __init setup_task_size(void)
868 int task_size = sizeof(struct task_struct);
870 if (!MACHINE_HAS_VX) {
871 task_size -= sizeof(__vector128) * __NUM_VXRS;
872 task_size += sizeof(freg_t) * __NUM_FPRS;
874 arch_task_struct_size = task_size;
878 * Setup function called from init/main.c just after the banner
882 void __init setup_arch(char **cmdline_p)
885 * print what head.S has found out about the machine
888 pr_info("Linux is running as a z/VM "
889 "guest operating system in 64-bit mode\n");
890 else if (MACHINE_IS_KVM)
891 pr_info("Linux is running under KVM in 64-bit mode\n");
892 else if (MACHINE_IS_LPAR)
893 pr_info("Linux is running natively in 64-bit mode\n");
895 pr_info("Linux is running as a guest in 64-bit mode\n");
897 /* Have one command line that is parsed and saved in /proc/cmdline */
898 /* boot_command_line has been already set up in early.c */
899 *cmdline_p = boot_command_line;
901 ROOT_DEV = Root_RAM0;
903 /* Is init_mm really needed? */
904 init_mm.start_code = PAGE_OFFSET;
905 init_mm.end_code = (unsigned long) _etext;
906 init_mm.end_data = (unsigned long) _edata;
907 init_mm.brk = (unsigned long) _end;
909 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
910 nospec_auto_detect();
913 #ifdef CONFIG_CRASH_DUMP
914 /* Deactivate elfcorehdr= kernel parameter */
915 elfcorehdr_addr = ELFCORE_ADDR_MAX;
922 /* Do some memory reservations *before* memory is added to memblock */
923 reserve_memory_end();
927 memblock_allow_resize();
929 /* Get information about *all* installed memory */
930 detect_memory_memblock();
935 * Make sure all chunks are MAX_ORDER aligned so we don't need the
936 * extra checks that HOLES_IN_ZONE would require.
938 * Is this still required?
940 memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
944 dma_contiguous_reserve(memory_end);
948 reserve_crashkernel();
949 #ifdef CONFIG_CRASH_DUMP
951 * Be aware that smp_save_dump_cpus() triggers a system reset.
952 * Therefore CPU and device initialization should be done afterwards.
954 smp_save_dump_cpus();
958 setup_lowcore_dat_off();
959 smp_fill_possible_mask();
960 cpu_detect_mhz_feature();
964 topology_init_early();
967 * Create kernel page tables and switch to virtual addressing.
972 * After paging_init created the kernel page table, the new PSWs
973 * in lowcore can now run with DAT enabled.
975 setup_lowcore_dat_on();
977 /* Setup default console */
979 set_preferred_console();
981 apply_alternative_instructions();
982 if (IS_ENABLED(CONFIG_EXPOLINE))
983 nospec_init_branches();
985 /* Setup zfcpdump support */
988 /* Add system specific data to the random pool */