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/root_dev.h>
38 #include <linux/console.h>
39 #include <linux/kernel_stat.h>
40 #include <linux/dma-contiguous.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>
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>
72 #include <asm/mem_detect.h>
78 unsigned int console_mode = 0;
79 EXPORT_SYMBOL(console_mode);
81 unsigned int console_devno = -1;
82 EXPORT_SYMBOL(console_devno);
84 unsigned int console_irq = -1;
85 EXPORT_SYMBOL(console_irq);
87 unsigned long elf_hwcap __read_mostly = 0;
88 char elf_platform[ELF_PLATFORM_SIZE];
90 unsigned long int_hwcap = 0;
92 int __bootdata(noexec_disabled);
93 int __bootdata(memory_end_set);
94 unsigned long __bootdata(memory_end);
95 unsigned long __bootdata(max_physmem_end);
96 struct mem_detect_info __bootdata(mem_detect);
98 unsigned long VMALLOC_START;
99 EXPORT_SYMBOL(VMALLOC_START);
101 unsigned long VMALLOC_END;
102 EXPORT_SYMBOL(VMALLOC_END);
104 struct page *vmemmap;
105 EXPORT_SYMBOL(vmemmap);
107 unsigned long MODULES_VADDR;
108 unsigned long MODULES_END;
110 /* An array with a pointer to the lowcore of every CPU. */
111 struct lowcore *lowcore_ptr[NR_CPUS];
112 EXPORT_SYMBOL(lowcore_ptr);
115 * This is set up by the setup-routine at boot-time
116 * for S390 need to find out, what we have to setup
117 * using address 0x10400 ...
120 #include <asm/setup.h>
123 * condev= and conmode= setup parameter.
126 static int __init condev_setup(char *str)
130 vdev = simple_strtoul(str, &str, 0);
131 if (vdev >= 0 && vdev < 65536) {
132 console_devno = vdev;
138 __setup("condev=", condev_setup);
140 static void __init set_preferred_console(void)
142 if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
143 add_preferred_console("ttyS", 0, NULL);
144 else if (CONSOLE_IS_3270)
145 add_preferred_console("tty3270", 0, NULL);
146 else if (CONSOLE_IS_VT220)
147 add_preferred_console("ttyS", 1, NULL);
148 else if (CONSOLE_IS_HVC)
149 add_preferred_console("hvc", 0, NULL);
152 static int __init conmode_setup(char *str)
154 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
155 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
158 #if defined(CONFIG_TN3215_CONSOLE)
159 if (strncmp(str, "3215", 5) == 0)
162 #if defined(CONFIG_TN3270_CONSOLE)
163 if (strncmp(str, "3270", 5) == 0)
166 set_preferred_console();
170 __setup("conmode=", conmode_setup);
172 static void __init conmode_default(void)
174 char query_buffer[1024];
178 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
179 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
180 ptr = strstr(query_buffer, "SUBCHANNEL =");
181 console_irq = simple_strtoul(ptr + 13, NULL, 16);
182 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
183 ptr = strstr(query_buffer, "CONMODE");
185 * Set the conmode to 3215 so that the device recognition
186 * will set the cu_type of the console to 3215. If the
187 * conmode is 3270 and we don't set it back then both
188 * 3215 and the 3270 driver will try to access the console
189 * device (3215 as console and 3270 as normal tty).
191 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
193 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
198 if (strncmp(ptr + 8, "3270", 4) == 0) {
199 #if defined(CONFIG_TN3270_CONSOLE)
201 #elif defined(CONFIG_TN3215_CONSOLE)
203 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
206 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
207 #if defined(CONFIG_TN3215_CONSOLE)
209 #elif defined(CONFIG_TN3270_CONSOLE)
211 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
215 } else if (MACHINE_IS_KVM) {
216 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
218 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
223 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
227 if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
228 conswitchp = &dummy_con;
231 #ifdef CONFIG_CRASH_DUMP
232 static void __init setup_zfcpdump(void)
234 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
238 strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
239 console_loglevel = 2;
242 static inline void setup_zfcpdump(void) {}
243 #endif /* CONFIG_CRASH_DUMP */
246 * Reboot, halt and power_off stubs. They just call _machine_restart,
247 * _machine_halt or _machine_power_off.
250 void machine_restart(char *command)
252 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
254 * Only unblank the console if we are called in enabled
255 * context or a bust_spinlocks cleared the way for us.
258 _machine_restart(command);
261 void machine_halt(void)
263 if (!in_interrupt() || oops_in_progress)
265 * Only unblank the console if we are called in enabled
266 * context or a bust_spinlocks cleared the way for us.
272 void machine_power_off(void)
274 if (!in_interrupt() || oops_in_progress)
276 * Only unblank the console if we are called in enabled
277 * context or a bust_spinlocks cleared the way for us.
280 _machine_power_off();
284 * Dummy power off function.
286 void (*pm_power_off)(void) = machine_power_off;
287 EXPORT_SYMBOL_GPL(pm_power_off);
289 static int __init parse_vmalloc(char *arg)
293 VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
296 early_param("vmalloc", parse_vmalloc);
298 void *restart_stack __section(.data);
300 unsigned long stack_alloc(void)
302 #ifdef CONFIG_VMAP_STACK
303 return (unsigned long)
304 __vmalloc_node_range(THREAD_SIZE, THREAD_SIZE,
305 VMALLOC_START, VMALLOC_END,
307 PAGE_KERNEL, 0, NUMA_NO_NODE,
308 __builtin_return_address(0));
310 return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
314 void stack_free(unsigned long stack)
316 #ifdef CONFIG_VMAP_STACK
317 vfree((void *) stack);
319 free_pages(stack, THREAD_SIZE_ORDER);
323 int __init arch_early_irq_init(void)
327 stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
329 panic("Couldn't allocate async stack");
330 S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
334 static int __init async_stack_realloc(void)
336 unsigned long old, new;
338 old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
341 panic("Couldn't allocate async stack");
342 S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
343 free_pages(old, THREAD_SIZE_ORDER);
346 early_initcall(async_stack_realloc);
348 void __init arch_call_rest_init(void)
350 struct stack_frame *frame;
353 stack = stack_alloc();
355 panic("Couldn't allocate kernel stack");
356 current->stack = (void *) stack;
357 #ifdef CONFIG_VMAP_STACK
358 current->stack_vm_area = (void *) stack;
360 set_task_stack_end_magic(current);
361 stack += STACK_INIT_OFFSET;
362 S390_lowcore.kernel_stack = stack;
363 frame = (struct stack_frame *) stack;
364 memset(frame, 0, sizeof(*frame));
365 /* Branch to rest_init on the new stack, never returns */
367 " la 15,0(%[_frame])\n"
369 : : [_frame] "a" (frame));
372 static void __init setup_lowcore_dat_off(void)
377 * Setup lowcore for boot cpu
379 BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
380 lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
381 lc->restart_psw.mask = PSW_KERNEL_BITS;
382 lc->restart_psw.addr = (unsigned long) restart_int_handler;
383 lc->external_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
384 lc->external_new_psw.addr = (unsigned long) ext_int_handler;
385 lc->svc_new_psw.mask = PSW_KERNEL_BITS |
386 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
387 lc->svc_new_psw.addr = (unsigned long) system_call;
388 lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
389 lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
390 lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
391 lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
392 lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
393 lc->io_new_psw.addr = (unsigned long) io_int_handler;
394 lc->clock_comparator = clock_comparator_max;
395 lc->nodat_stack = ((unsigned long) &init_thread_union)
396 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
397 lc->current_task = (unsigned long)&init_task;
399 lc->machine_flags = S390_lowcore.machine_flags;
400 lc->preempt_count = S390_lowcore.preempt_count;
401 lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
402 memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
403 sizeof(lc->stfle_fac_list));
404 memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
405 sizeof(lc->alt_stfle_fac_list));
406 nmi_alloc_boot_cpu(lc);
407 vdso_alloc_boot_cpu(lc);
408 lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
409 lc->async_enter_timer = S390_lowcore.async_enter_timer;
410 lc->exit_timer = S390_lowcore.exit_timer;
411 lc->user_timer = S390_lowcore.user_timer;
412 lc->system_timer = S390_lowcore.system_timer;
413 lc->steal_timer = S390_lowcore.steal_timer;
414 lc->last_update_timer = S390_lowcore.last_update_timer;
415 lc->last_update_clock = S390_lowcore.last_update_clock;
418 * Allocate the global restart stack which is the same for
419 * all CPUs in cast *one* of them does a PSW restart.
421 restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
422 restart_stack += STACK_INIT_OFFSET;
425 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
426 * restart data to the absolute zero lowcore. This is necessary if
427 * PSW restart is done on an offline CPU that has lowcore zero.
429 lc->restart_stack = (unsigned long) restart_stack;
430 lc->restart_fn = (unsigned long) do_restart;
431 lc->restart_data = 0;
432 lc->restart_source = -1UL;
434 /* Setup absolute zero lowcore */
435 mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
436 mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
437 mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
438 mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
439 mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
442 lc->spinlock_lockval = arch_spin_lockval(0);
443 lc->spinlock_index = 0;
444 arch_spin_lock_setup(0);
446 lc->br_r1_trampoline = 0x07f1; /* br %r1 */
448 set_prefix((u32)(unsigned long) lc);
452 static void __init setup_lowcore_dat_on(void)
454 __ctl_clear_bit(0, 28);
455 S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
456 S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
457 S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
458 S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
459 __ctl_set_bit(0, 28);
462 static struct resource code_resource = {
463 .name = "Kernel code",
464 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
467 static struct resource data_resource = {
468 .name = "Kernel data",
469 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
472 static struct resource bss_resource = {
473 .name = "Kernel bss",
474 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
477 static struct resource __initdata *standard_resources[] = {
483 static void __init setup_resources(void)
485 struct resource *res, *std_res, *sub_res;
486 struct memblock_region *reg;
489 code_resource.start = (unsigned long) _text;
490 code_resource.end = (unsigned long) _etext - 1;
491 data_resource.start = (unsigned long) _etext;
492 data_resource.end = (unsigned long) _edata - 1;
493 bss_resource.start = (unsigned long) __bss_start;
494 bss_resource.end = (unsigned long) __bss_stop - 1;
496 for_each_memblock(memory, reg) {
497 res = memblock_alloc(sizeof(*res), 8);
498 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
500 res->name = "System RAM";
501 res->start = reg->base;
502 res->end = reg->base + reg->size - 1;
503 request_resource(&iomem_resource, res);
505 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
506 std_res = standard_resources[j];
507 if (std_res->start < res->start ||
508 std_res->start > res->end)
510 if (std_res->end > res->end) {
511 sub_res = memblock_alloc(sizeof(*sub_res), 8);
513 sub_res->end = res->end;
514 std_res->start = res->end + 1;
515 request_resource(res, sub_res);
517 request_resource(res, std_res);
521 #ifdef CONFIG_CRASH_DUMP
523 * Re-add removed crash kernel memory as reserved memory. This makes
524 * sure it will be mapped with the identity mapping and struct pages
525 * will be created, so it can be resized later on.
526 * However add it later since the crash kernel resource should not be
527 * part of the System RAM resource.
529 if (crashk_res.end) {
530 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
531 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
532 insert_resource(&iomem_resource, &crashk_res);
537 static void __init setup_memory_end(void)
539 unsigned long vmax, vmalloc_size, tmp;
541 /* Choose kernel address space layout: 3 or 4 levels. */
542 vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
543 if (IS_ENABLED(CONFIG_KASAN)) {
544 vmax = IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)
548 tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
549 tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
550 if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
551 vmax = _REGION2_SIZE; /* 3-level kernel page table */
553 vmax = _REGION1_SIZE; /* 4-level kernel page table */
556 /* module area is at the end of the kernel address space. */
558 MODULES_VADDR = MODULES_END - MODULES_LEN;
559 VMALLOC_END = MODULES_VADDR;
560 VMALLOC_START = VMALLOC_END - vmalloc_size;
562 /* Split remaining virtual space between 1:1 mapping & vmemmap array */
563 tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
564 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
565 tmp = SECTION_ALIGN_UP(tmp);
566 tmp = VMALLOC_START - tmp * sizeof(struct page);
567 tmp &= ~((vmax >> 11) - 1); /* align to page table level */
568 tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
569 vmemmap = (struct page *) tmp;
571 /* Take care that memory_end is set and <= vmemmap */
572 memory_end = min(memory_end ?: max_physmem_end, (unsigned long)vmemmap);
574 /* fit in kasan shadow memory region between 1:1 and vmemmap */
575 memory_end = min(memory_end, KASAN_SHADOW_START);
576 vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
578 max_pfn = max_low_pfn = PFN_DOWN(memory_end);
579 memblock_remove(memory_end, ULONG_MAX);
581 pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
584 #ifdef CONFIG_CRASH_DUMP
587 * When kdump is enabled, we have to ensure that no memory from
588 * the area [0 - crashkernel memory size] and
589 * [crashk_res.start - crashk_res.end] is set offline.
591 static int kdump_mem_notifier(struct notifier_block *nb,
592 unsigned long action, void *data)
594 struct memory_notify *arg = data;
596 if (action != MEM_GOING_OFFLINE)
598 if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
600 if (arg->start_pfn > PFN_DOWN(crashk_res.end))
602 if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
607 static struct notifier_block kdump_mem_nb = {
608 .notifier_call = kdump_mem_notifier,
614 * Make sure that the area behind memory_end is protected
616 static void reserve_memory_end(void)
619 memblock_reserve(memory_end, ULONG_MAX);
623 * Make sure that oldmem, where the dump is stored, is protected
625 static void reserve_oldmem(void)
627 #ifdef CONFIG_CRASH_DUMP
629 /* Forget all memory above the running kdump system */
630 memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
635 * Make sure that oldmem, where the dump is stored, is protected
637 static void remove_oldmem(void)
639 #ifdef CONFIG_CRASH_DUMP
641 /* Forget all memory above the running kdump system */
642 memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
647 * Reserve memory for kdump kernel to be loaded with kexec
649 static void __init reserve_crashkernel(void)
651 #ifdef CONFIG_CRASH_DUMP
652 unsigned long long crash_base, crash_size;
653 phys_addr_t low, high;
656 rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
659 crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
660 crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
661 if (rc || crash_size == 0)
664 if (memblock.memory.regions[0].size < crash_size) {
665 pr_info("crashkernel reservation failed: %s\n",
666 "first memory chunk must be at least crashkernel size");
670 low = crash_base ?: OLDMEM_BASE;
671 high = low + crash_size;
672 if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
673 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
676 /* Find suitable area in free memory */
677 low = max_t(unsigned long, crash_size, sclp.hsa_size);
678 high = crash_base ? crash_base + crash_size : ULONG_MAX;
680 if (crash_base && crash_base < low) {
681 pr_info("crashkernel reservation failed: %s\n",
682 "crash_base too low");
685 low = crash_base ?: low;
686 crash_base = memblock_find_in_range(low, high, crash_size,
687 KEXEC_CRASH_MEM_ALIGN);
691 pr_info("crashkernel reservation failed: %s\n",
692 "no suitable area found");
696 if (register_memory_notifier(&kdump_mem_nb))
699 if (!OLDMEM_BASE && MACHINE_IS_VM)
700 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
701 crashk_res.start = crash_base;
702 crashk_res.end = crash_base + crash_size - 1;
703 memblock_remove(crash_base, crash_size);
704 pr_info("Reserving %lluMB of memory at %lluMB "
705 "for crashkernel (System RAM: %luMB)\n",
706 crash_size >> 20, crash_base >> 20,
707 (unsigned long)memblock.memory.total_size >> 20);
708 os_info_crashkernel_add(crash_base, crash_size);
713 * Reserve the initrd from being used by memblock
715 static void __init reserve_initrd(void)
717 #ifdef CONFIG_BLK_DEV_INITRD
718 if (!INITRD_START || !INITRD_SIZE)
720 initrd_start = INITRD_START;
721 initrd_end = initrd_start + INITRD_SIZE;
722 memblock_reserve(INITRD_START, INITRD_SIZE);
726 static void __init reserve_mem_detect_info(void)
728 unsigned long start, size;
730 get_mem_detect_reserved(&start, &size);
732 memblock_reserve(start, size);
735 static void __init free_mem_detect_info(void)
737 unsigned long start, size;
739 get_mem_detect_reserved(&start, &size);
741 memblock_free(start, size);
744 static void __init memblock_physmem_add(phys_addr_t start, phys_addr_t size)
746 memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
747 start, start + size - 1);
748 memblock_add_range(&memblock.memory, start, size, 0, 0);
749 memblock_add_range(&memblock.physmem, start, size, 0, 0);
752 static const char * __init get_mem_info_source(void)
754 switch (mem_detect.info_source) {
755 case MEM_DETECT_SCLP_STOR_INFO:
756 return "sclp storage info";
757 case MEM_DETECT_DIAG260:
759 case MEM_DETECT_SCLP_READ_INFO:
760 return "sclp read info";
761 case MEM_DETECT_BIN_SEARCH:
762 return "binary search";
767 static void __init memblock_add_mem_detect_info(void)
769 unsigned long start, end;
772 memblock_dbg("physmem info source: %s (%hhd)\n",
773 get_mem_info_source(), mem_detect.info_source);
774 /* keep memblock lists close to the kernel */
775 memblock_set_bottom_up(true);
776 for_each_mem_detect_block(i, &start, &end)
777 memblock_physmem_add(start, end - start);
778 memblock_set_bottom_up(false);
783 * Check for initrd being in usable memory
785 static void __init check_initrd(void)
787 #ifdef CONFIG_BLK_DEV_INITRD
788 if (INITRD_START && INITRD_SIZE &&
789 !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
790 pr_err("The initial RAM disk does not fit into the memory\n");
791 memblock_free(INITRD_START, INITRD_SIZE);
792 initrd_start = initrd_end = 0;
798 * Reserve memory used for lowcore/command line/kernel image.
800 static void __init reserve_kernel(void)
802 unsigned long start_pfn = PFN_UP(__pa(_end));
804 memblock_reserve(0, PARMAREA_END);
805 memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
806 - (unsigned long)_stext);
809 static void __init setup_memory(void)
811 struct memblock_region *reg;
814 * Init storage key for present memory
816 for_each_memblock(memory, reg) {
817 storage_key_init_range(reg->base, reg->base + reg->size);
819 psw_set_key(PAGE_DEFAULT_KEY);
822 memblock_enforce_memory_limit(memblock_end_of_DRAM());
826 * Setup hardware capabilities.
828 static int __init setup_hwcaps(void)
830 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
835 * The store facility list bits numbers as found in the principles
836 * of operation are numbered with bit 1UL<<31 as number 0 to
837 * bit 1UL<<0 as number 31.
838 * Bit 0: instructions named N3, "backported" to esa-mode
839 * Bit 2: z/Architecture mode is active
840 * Bit 7: the store-facility-list-extended facility is installed
841 * Bit 17: the message-security assist is installed
842 * Bit 19: the long-displacement facility is installed
843 * Bit 21: the extended-immediate facility is installed
844 * Bit 22: extended-translation facility 3 is installed
845 * Bit 30: extended-translation facility 3 enhancement facility
846 * These get translated to:
847 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
848 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
849 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
850 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
852 for (i = 0; i < 6; i++)
853 if (test_facility(stfl_bits[i]))
854 elf_hwcap |= 1UL << i;
856 if (test_facility(22) && test_facility(30))
857 elf_hwcap |= HWCAP_S390_ETF3EH;
860 * Check for additional facilities with store-facility-list-extended.
861 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
862 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
863 * as stored by stfl, bits 32-xxx contain additional facilities.
864 * How many facility words are stored depends on the number of
865 * doublewords passed to the instruction. The additional facilities
867 * Bit 42: decimal floating point facility is installed
868 * Bit 44: perform floating point operation facility is installed
870 * HWCAP_S390_DFP bit 6 (42 && 44).
872 if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
873 elf_hwcap |= HWCAP_S390_DFP;
876 * Huge page support HWCAP_S390_HPAGE is bit 7.
878 if (MACHINE_HAS_EDAT1)
879 elf_hwcap |= HWCAP_S390_HPAGE;
882 * 64-bit register support for 31-bit processes
883 * HWCAP_S390_HIGH_GPRS is bit 9.
885 elf_hwcap |= HWCAP_S390_HIGH_GPRS;
888 * Transactional execution support HWCAP_S390_TE is bit 10.
891 elf_hwcap |= HWCAP_S390_TE;
894 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
895 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
896 * instead of facility bit 129.
898 if (MACHINE_HAS_VX) {
899 elf_hwcap |= HWCAP_S390_VXRS;
900 if (test_facility(134))
901 elf_hwcap |= HWCAP_S390_VXRS_EXT;
902 if (test_facility(135))
903 elf_hwcap |= HWCAP_S390_VXRS_BCD;
907 * Guarded storage support HWCAP_S390_GS is bit 12.
910 elf_hwcap |= HWCAP_S390_GS;
913 add_device_randomness(&cpu_id, sizeof(cpu_id));
914 switch (cpu_id.machine) {
917 default: /* Use "z900" as default for 64 bit kernels. */
918 strcpy(elf_platform, "z900");
922 strcpy(elf_platform, "z990");
926 strcpy(elf_platform, "z9-109");
930 strcpy(elf_platform, "z10");
934 strcpy(elf_platform, "z196");
938 strcpy(elf_platform, "zEC12");
942 strcpy(elf_platform, "z13");
946 strcpy(elf_platform, "z14");
951 * Virtualization support HWCAP_INT_SIE is bit 0.
954 int_hwcap |= HWCAP_INT_SIE;
958 arch_initcall(setup_hwcaps);
961 * Add system information as device randomness
963 static void __init setup_randomness(void)
965 struct sysinfo_3_2_2 *vmms;
967 vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
969 if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
970 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
971 memblock_free((unsigned long) vmms, PAGE_SIZE);
975 * Find the correct size for the task_struct. This depends on
976 * the size of the struct fpu at the end of the thread_struct
977 * which is embedded in the task_struct.
979 static void __init setup_task_size(void)
981 int task_size = sizeof(struct task_struct);
983 if (!MACHINE_HAS_VX) {
984 task_size -= sizeof(__vector128) * __NUM_VXRS;
985 task_size += sizeof(freg_t) * __NUM_FPRS;
987 arch_task_struct_size = task_size;
991 * Issue diagnose 318 to set the control program name and
994 static void __init setup_control_program_code(void)
996 union diag318_info diag318_info = {
1002 if (!sclp.has_diag318)
1005 diag_stat_inc(DIAG_STAT_X318);
1006 asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1010 * Setup function called from init/main.c just after the banner
1014 void __init setup_arch(char **cmdline_p)
1017 * print what head.S has found out about the machine
1020 pr_info("Linux is running as a z/VM "
1021 "guest operating system in 64-bit mode\n");
1022 else if (MACHINE_IS_KVM)
1023 pr_info("Linux is running under KVM in 64-bit mode\n");
1024 else if (MACHINE_IS_LPAR)
1025 pr_info("Linux is running natively in 64-bit mode\n");
1027 pr_info("Linux is running as a guest in 64-bit mode\n");
1029 /* Have one command line that is parsed and saved in /proc/cmdline */
1030 /* boot_command_line has been already set up in early.c */
1031 *cmdline_p = boot_command_line;
1033 ROOT_DEV = Root_RAM0;
1035 /* Is init_mm really needed? */
1036 init_mm.start_code = PAGE_OFFSET;
1037 init_mm.end_code = (unsigned long) _etext;
1038 init_mm.end_data = (unsigned long) _edata;
1039 init_mm.brk = (unsigned long) _end;
1041 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1042 nospec_auto_detect();
1044 parse_early_param();
1045 #ifdef CONFIG_CRASH_DUMP
1046 /* Deactivate elfcorehdr= kernel parameter */
1047 elfcorehdr_addr = ELFCORE_ADDR_MAX;
1053 setup_control_program_code();
1055 /* Do some memory reservations *before* memory is added to memblock */
1056 reserve_memory_end();
1060 reserve_mem_detect_info();
1061 memblock_allow_resize();
1063 /* Get information about *all* installed memory */
1064 memblock_add_mem_detect_info();
1066 free_mem_detect_info();
1070 * Make sure all chunks are MAX_ORDER aligned so we don't need the
1071 * extra checks that HOLES_IN_ZONE would require.
1073 * Is this still required?
1075 memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
1079 dma_contiguous_reserve(memory_end);
1083 reserve_crashkernel();
1084 #ifdef CONFIG_CRASH_DUMP
1086 * Be aware that smp_save_dump_cpus() triggers a system reset.
1087 * Therefore CPU and device initialization should be done afterwards.
1089 smp_save_dump_cpus();
1093 setup_lowcore_dat_off();
1094 smp_fill_possible_mask();
1095 cpu_detect_mhz_feature();
1099 topology_init_early();
1102 * Create kernel page tables and switch to virtual addressing.
1107 * After paging_init created the kernel page table, the new PSWs
1108 * in lowcore can now run with DAT enabled.
1110 setup_lowcore_dat_on();
1112 /* Setup default console */
1114 set_preferred_console();
1116 apply_alternative_instructions();
1117 if (IS_ENABLED(CONFIG_EXPOLINE))
1118 nospec_init_branches();
1120 /* Setup zfcpdump support */
1123 /* Add system specific data to the random pool */