2 * arch/s390/kernel/setup.c
5 * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Hartmut Penner (hp@de.ibm.com),
7 * Martin Schwidefsky (schwidefsky@de.ibm.com)
9 * Derived from "arch/i386/kernel/setup.c"
10 * Copyright (C) 1995, Linus Torvalds
14 * This file handles the architecture-dependent parts of initialization
17 #define KMSG_COMPONENT "setup"
18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
25 #include <linux/stddef.h>
26 #include <linux/unistd.h>
27 #include <linux/ptrace.h>
28 #include <linux/slab.h>
29 #include <linux/user.h>
30 #include <linux/tty.h>
31 #include <linux/ioport.h>
32 #include <linux/delay.h>
33 #include <linux/init.h>
34 #include <linux/initrd.h>
35 #include <linux/bootmem.h>
36 #include <linux/root_dev.h>
37 #include <linux/console.h>
38 #include <linux/kernel_stat.h>
39 #include <linux/device.h>
40 #include <linux/notifier.h>
41 #include <linux/pfn.h>
42 #include <linux/ctype.h>
43 #include <linux/reboot.h>
44 #include <linux/topology.h>
47 #include <asm/uaccess.h>
48 #include <asm/system.h>
50 #include <asm/mmu_context.h>
51 #include <asm/cpcmd.h>
52 #include <asm/lowcore.h>
55 #include <asm/ptrace.h>
56 #include <asm/sections.h>
57 #include <asm/ebcdic.h>
58 #include <asm/compat.h>
59 #include <asm/kvm_virtio.h>
61 long psw_kernel_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
62 PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
63 long psw_user_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
64 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
65 PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
68 * User copy operations.
70 struct uaccess_ops uaccess;
71 EXPORT_SYMBOL(uaccess);
76 unsigned int console_mode = 0;
77 EXPORT_SYMBOL(console_mode);
79 unsigned int console_devno = -1;
80 EXPORT_SYMBOL(console_devno);
82 unsigned int console_irq = -1;
83 EXPORT_SYMBOL(console_irq);
85 unsigned long machine_flags;
86 EXPORT_SYMBOL(machine_flags);
88 unsigned long elf_hwcap = 0;
89 char elf_platform[ELF_PLATFORM_SIZE];
91 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
92 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
94 int __initdata memory_end_set;
95 unsigned long __initdata memory_end;
97 /* An array with a pointer to the lowcore of every CPU. */
98 struct _lowcore *lowcore_ptr[NR_CPUS];
99 EXPORT_SYMBOL(lowcore_ptr);
102 * This is set up by the setup-routine at boot-time
103 * for S390 need to find out, what we have to setup
104 * using address 0x10400 ...
107 #include <asm/setup.h>
109 static struct resource code_resource = {
110 .name = "Kernel code",
111 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
114 static struct resource data_resource = {
115 .name = "Kernel data",
116 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
120 * cpu_init() initializes state that is per-CPU.
122 void __cpuinit cpu_init(void)
124 int addr = hard_smp_processor_id();
127 * Store processor id in lowcore (used e.g. in timer_interrupt)
129 get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
130 S390_lowcore.cpu_data.cpu_addr = addr;
133 * Force FPU initialization:
135 clear_thread_flag(TIF_USEDFPU);
138 atomic_inc(&init_mm.mm_count);
139 current->active_mm = &init_mm;
142 enter_lazy_tlb(&init_mm, current);
146 * condev= and conmode= setup parameter.
149 static int __init condev_setup(char *str)
153 vdev = simple_strtoul(str, &str, 0);
154 if (vdev >= 0 && vdev < 65536) {
155 console_devno = vdev;
161 __setup("condev=", condev_setup);
163 static int __init conmode_setup(char *str)
165 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
166 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
169 #if defined(CONFIG_TN3215_CONSOLE)
170 if (strncmp(str, "3215", 5) == 0)
173 #if defined(CONFIG_TN3270_CONSOLE)
174 if (strncmp(str, "3270", 5) == 0)
180 __setup("conmode=", conmode_setup);
182 static void __init conmode_default(void)
184 char query_buffer[1024];
188 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
189 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
190 ptr = strstr(query_buffer, "SUBCHANNEL =");
191 console_irq = simple_strtoul(ptr + 13, NULL, 16);
192 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
193 ptr = strstr(query_buffer, "CONMODE");
195 * Set the conmode to 3215 so that the device recognition
196 * will set the cu_type of the console to 3215. If the
197 * conmode is 3270 and we don't set it back then both
198 * 3215 and the 3270 driver will try to access the console
199 * device (3215 as console and 3270 as normal tty).
201 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
203 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208 if (strncmp(ptr + 8, "3270", 4) == 0) {
209 #if defined(CONFIG_TN3270_CONSOLE)
211 #elif defined(CONFIG_TN3215_CONSOLE)
213 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
216 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
217 #if defined(CONFIG_TN3215_CONSOLE)
219 #elif defined(CONFIG_TN3270_CONSOLE)
221 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
226 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
232 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
233 static void __init setup_zfcpdump(unsigned int console_devno)
237 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
239 if (console_devno != -1)
240 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
241 ipl_info.data.fcp.dev_id.devno, console_devno);
243 sprintf(str, " cio_ignore=all,!0.0.%04x",
244 ipl_info.data.fcp.dev_id.devno);
245 strcat(boot_command_line, str);
246 console_loglevel = 2;
249 static inline void setup_zfcpdump(unsigned int console_devno) {}
250 #endif /* CONFIG_ZFCPDUMP */
253 * Reboot, halt and power_off stubs. They just call _machine_restart,
254 * _machine_halt or _machine_power_off.
257 void machine_restart(char *command)
259 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
261 * Only unblank the console if we are called in enabled
262 * context or a bust_spinlocks cleared the way for us.
265 _machine_restart(command);
268 void machine_halt(void)
270 if (!in_interrupt() || oops_in_progress)
272 * Only unblank the console if we are called in enabled
273 * context or a bust_spinlocks cleared the way for us.
279 void machine_power_off(void)
281 if (!in_interrupt() || oops_in_progress)
283 * Only unblank the console if we are called in enabled
284 * context or a bust_spinlocks cleared the way for us.
287 _machine_power_off();
291 * Dummy power off function.
293 void (*pm_power_off)(void) = machine_power_off;
295 static int __init early_parse_mem(char *p)
297 memory_end = memparse(p, &p);
301 early_param("mem", early_parse_mem);
303 #ifdef CONFIG_S390_SWITCH_AMODE
305 unsigned int switch_amode = 1;
307 unsigned int switch_amode = 0;
309 EXPORT_SYMBOL_GPL(switch_amode);
311 static int set_amode_and_uaccess(unsigned long user_amode,
312 unsigned long user32_amode)
314 psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
315 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
316 PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
318 psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
319 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
320 PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
321 psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
322 PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
325 psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
326 PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
328 if (MACHINE_HAS_MVCOS) {
329 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
332 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
338 * Switch kernel/user addressing modes?
340 static int __init early_parse_switch_amode(char *p)
345 early_param("switch_amode", early_parse_switch_amode);
347 #else /* CONFIG_S390_SWITCH_AMODE */
348 static inline int set_amode_and_uaccess(unsigned long user_amode,
349 unsigned long user32_amode)
353 #endif /* CONFIG_S390_SWITCH_AMODE */
355 #ifdef CONFIG_S390_EXEC_PROTECT
356 unsigned int s390_noexec = 0;
357 EXPORT_SYMBOL_GPL(s390_noexec);
360 * Enable execute protection?
362 static int __init early_parse_noexec(char *p)
364 if (!strncmp(p, "off", 3))
370 early_param("noexec", early_parse_noexec);
371 #endif /* CONFIG_S390_EXEC_PROTECT */
373 static void setup_addressing_mode(void)
376 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
377 PSW32_ASC_SECONDARY))
378 pr_info("Execute protection active, "
379 "mvcos available\n");
381 pr_info("Execute protection active, "
382 "mvcos not available\n");
383 } else if (switch_amode) {
384 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
385 pr_info("Address spaces switched, "
386 "mvcos available\n");
388 pr_info("Address spaces switched, "
389 "mvcos not available\n");
391 #ifdef CONFIG_TRACE_IRQFLAGS
392 sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
393 io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
404 * Setup lowcore for boot cpu
406 lc_pages = sizeof(void *) == 8 ? 2 : 1;
407 lc = (struct _lowcore *)
408 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
409 memset(lc, 0, lc_pages * PAGE_SIZE);
410 lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
411 lc->restart_psw.addr =
412 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
414 lc->restart_psw.mask |= PSW_ASC_HOME;
415 lc->external_new_psw.mask = psw_kernel_bits;
416 lc->external_new_psw.addr =
417 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
418 lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
419 lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
420 lc->program_new_psw.mask = psw_kernel_bits;
421 lc->program_new_psw.addr =
422 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
423 lc->mcck_new_psw.mask =
424 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
425 lc->mcck_new_psw.addr =
426 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
427 lc->io_new_psw.mask = psw_kernel_bits;
428 lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
429 lc->ipl_device = S390_lowcore.ipl_device;
430 lc->clock_comparator = -1ULL;
431 lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
432 lc->async_stack = (unsigned long)
433 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
434 lc->panic_stack = (unsigned long)
435 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
436 lc->current_task = (unsigned long) init_thread_union.thread_info.task;
437 lc->thread_info = (unsigned long) &init_thread_union;
439 if (MACHINE_HAS_IEEE) {
440 lc->extended_save_area_addr = (__u32)
441 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
442 /* enable extended save area */
443 __ctl_set_bit(14, 29);
446 lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
448 set_prefix((u32)(unsigned long) lc);
453 setup_resources(void)
455 struct resource *res, *sub_res;
458 code_resource.start = (unsigned long) &_text;
459 code_resource.end = (unsigned long) &_etext - 1;
460 data_resource.start = (unsigned long) &_etext;
461 data_resource.end = (unsigned long) &_edata - 1;
463 for (i = 0; i < MEMORY_CHUNKS; i++) {
464 if (!memory_chunk[i].size)
466 res = alloc_bootmem_low(sizeof(struct resource));
467 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
468 switch (memory_chunk[i].type) {
469 case CHUNK_READ_WRITE:
470 res->name = "System RAM";
472 case CHUNK_READ_ONLY:
473 res->name = "System ROM";
474 res->flags |= IORESOURCE_READONLY;
477 res->name = "reserved";
479 res->start = memory_chunk[i].addr;
480 res->end = memory_chunk[i].addr + memory_chunk[i].size - 1;
481 request_resource(&iomem_resource, res);
483 if (code_resource.start >= res->start &&
484 code_resource.start <= res->end &&
485 code_resource.end > res->end) {
486 sub_res = alloc_bootmem_low(sizeof(struct resource));
487 memcpy(sub_res, &code_resource,
488 sizeof(struct resource));
489 sub_res->end = res->end;
490 code_resource.start = res->end + 1;
491 request_resource(res, sub_res);
494 if (code_resource.start >= res->start &&
495 code_resource.start <= res->end &&
496 code_resource.end <= res->end)
497 request_resource(res, &code_resource);
499 if (data_resource.start >= res->start &&
500 data_resource.start <= res->end &&
501 data_resource.end > res->end) {
502 sub_res = alloc_bootmem_low(sizeof(struct resource));
503 memcpy(sub_res, &data_resource,
504 sizeof(struct resource));
505 sub_res->end = res->end;
506 data_resource.start = res->end + 1;
507 request_resource(res, sub_res);
510 if (data_resource.start >= res->start &&
511 data_resource.start <= res->end &&
512 data_resource.end <= res->end)
513 request_resource(res, &data_resource);
517 unsigned long real_memory_size;
518 EXPORT_SYMBOL_GPL(real_memory_size);
520 static void __init setup_memory_end(void)
522 unsigned long memory_size;
523 unsigned long max_mem;
526 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
527 if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
528 memory_end = ZFCPDUMP_HSA_SIZE;
533 memory_end &= PAGE_MASK;
535 max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
536 memory_end = min(max_mem, memory_end);
539 * Make sure all chunks are MAX_ORDER aligned so we don't need the
540 * extra checks that HOLES_IN_ZONE would require.
542 for (i = 0; i < MEMORY_CHUNKS; i++) {
543 unsigned long start, end;
544 struct mem_chunk *chunk;
547 chunk = &memory_chunk[i];
548 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
549 start = (chunk->addr + align - 1) & ~(align - 1);
550 end = (chunk->addr + chunk->size) & ~(align - 1);
552 memset(chunk, 0, sizeof(*chunk));
555 chunk->size = end - start;
559 for (i = 0; i < MEMORY_CHUNKS; i++) {
560 struct mem_chunk *chunk = &memory_chunk[i];
562 real_memory_size = max(real_memory_size,
563 chunk->addr + chunk->size);
564 if (chunk->addr >= max_mem) {
565 memset(chunk, 0, sizeof(*chunk));
568 if (chunk->addr + chunk->size > max_mem)
569 chunk->size = max_mem - chunk->addr;
570 memory_size = max(memory_size, chunk->addr + chunk->size);
573 memory_end = memory_size;
579 unsigned long bootmap_size;
580 unsigned long start_pfn, end_pfn;
584 * partially used pages are not usable - thus
585 * we are rounding upwards:
587 start_pfn = PFN_UP(__pa(&_end));
588 end_pfn = max_pfn = PFN_DOWN(memory_end);
590 #ifdef CONFIG_BLK_DEV_INITRD
592 * Move the initrd in case the bitmap of the bootmem allocater
593 * would overwrite it.
596 if (INITRD_START && INITRD_SIZE) {
597 unsigned long bmap_size;
600 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
601 bmap_size = PFN_PHYS(bmap_size);
603 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
604 start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
606 if (start + INITRD_SIZE > memory_end) {
607 pr_err("initrd extends beyond end of "
608 "memory (0x%08lx > 0x%08lx) "
609 "disabling initrd\n",
610 start + INITRD_SIZE, memory_end);
611 INITRD_START = INITRD_SIZE = 0;
613 pr_info("Moving initrd (0x%08lx -> "
614 "0x%08lx, size: %ld)\n",
615 INITRD_START, start, INITRD_SIZE);
616 memmove((void *) start, (void *) INITRD_START,
618 INITRD_START = start;
625 * Initialize the boot-time allocator
627 bootmap_size = init_bootmem(start_pfn, end_pfn);
630 * Register RAM areas with the bootmem allocator.
633 for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
634 unsigned long start_chunk, end_chunk, pfn;
636 if (memory_chunk[i].type != CHUNK_READ_WRITE)
638 start_chunk = PFN_DOWN(memory_chunk[i].addr);
639 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
640 end_chunk = min(end_chunk, end_pfn);
641 if (start_chunk >= end_chunk)
643 add_active_range(0, start_chunk, end_chunk);
644 pfn = max(start_chunk, start_pfn);
645 for (; pfn < end_chunk; pfn++)
646 page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
649 psw_set_key(PAGE_DEFAULT_KEY);
651 free_bootmem_with_active_regions(0, max_pfn);
654 * Reserve memory used for lowcore/command line/kernel image.
656 reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
657 reserve_bootmem((unsigned long)_stext,
658 PFN_PHYS(start_pfn) - (unsigned long)_stext,
661 * Reserve the bootmem bitmap itself as well. We do this in two
662 * steps (first step was init_bootmem()) because this catches
663 * the (very unlikely) case of us accidentally initializing the
664 * bootmem allocator with an invalid RAM area.
666 reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
669 #ifdef CONFIG_BLK_DEV_INITRD
670 if (INITRD_START && INITRD_SIZE) {
671 if (INITRD_START + INITRD_SIZE <= memory_end) {
672 reserve_bootmem(INITRD_START, INITRD_SIZE,
674 initrd_start = INITRD_START;
675 initrd_end = initrd_start + INITRD_SIZE;
677 pr_err("initrd extends beyond end of "
678 "memory (0x%08lx > 0x%08lx) "
679 "disabling initrd\n",
680 initrd_start + INITRD_SIZE, memory_end);
681 initrd_start = initrd_end = 0;
688 * Setup hardware capabilities.
690 static void __init setup_hwcaps(void)
692 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
693 struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
694 unsigned long long facility_list_extended;
695 unsigned int facility_list;
698 facility_list = stfl();
700 * The store facility list bits numbers as found in the principles
701 * of operation are numbered with bit 1UL<<31 as number 0 to
702 * bit 1UL<<0 as number 31.
703 * Bit 0: instructions named N3, "backported" to esa-mode
704 * Bit 2: z/Architecture mode is active
705 * Bit 7: the store-facility-list-extended facility is installed
706 * Bit 17: the message-security assist is installed
707 * Bit 19: the long-displacement facility is installed
708 * Bit 21: the extended-immediate facility is installed
709 * These get translated to:
710 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
711 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
712 * HWCAP_S390_LDISP bit 4, and HWCAP_S390_EIMM bit 5.
714 for (i = 0; i < 6; i++)
715 if (facility_list & (1UL << (31 - stfl_bits[i])))
716 elf_hwcap |= 1UL << i;
719 * Check for additional facilities with store-facility-list-extended.
720 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
721 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
722 * as stored by stfl, bits 32-xxx contain additional facilities.
723 * How many facility words are stored depends on the number of
724 * doublewords passed to the instruction. The additional facilites
726 * Bit 43: decimal floating point facility is installed
728 * HWCAP_S390_DFP bit 6.
730 if ((elf_hwcap & (1UL << 2)) &&
731 __stfle(&facility_list_extended, 1) > 0) {
732 if (facility_list_extended & (1ULL << (64 - 43)))
733 elf_hwcap |= 1UL << 6;
736 if (MACHINE_HAS_HPAGE)
737 elf_hwcap |= 1UL << 7;
739 switch (cpuinfo->cpu_id.machine) {
741 #if !defined(CONFIG_64BIT)
742 default: /* Use "g5" as default for 31 bit kernels. */
744 strcpy(elf_platform, "g5");
748 #if defined(CONFIG_64BIT)
749 default: /* Use "z900" as default for 64 bit kernels. */
751 strcpy(elf_platform, "z900");
755 strcpy(elf_platform, "z990");
759 strcpy(elf_platform, "z9-109");
763 strcpy(elf_platform, "z10");
769 * Setup function called from init/main.c just after the banner
774 setup_arch(char **cmdline_p)
776 /* set up preferred console */
777 add_preferred_console("ttyS", 0, NULL);
780 * print what head.S has found out about the machine
784 pr_info("Linux is running as a z/VM "
785 "guest operating system in 31-bit mode\n");
787 pr_info("Linux is running natively in 31-bit mode\n");
788 if (MACHINE_HAS_IEEE)
789 pr_info("The hardware system has IEEE compatible "
790 "floating point units\n");
792 pr_info("The hardware system has no IEEE compatible "
793 "floating point units\n");
794 #else /* CONFIG_64BIT */
796 pr_info("Linux is running as a z/VM "
797 "guest operating system in 64-bit mode\n");
798 else if (MACHINE_IS_KVM) {
799 pr_info("Linux is running under KVM in 64-bit mode\n");
800 add_preferred_console("hvc", 0, NULL);
801 s390_virtio_console_init();
803 pr_info("Linux is running natively in 64-bit mode\n");
804 #endif /* CONFIG_64BIT */
806 /* Have one command line that is parsed and saved in /proc/cmdline */
807 /* boot_command_line has been already set up in early.c */
808 *cmdline_p = boot_command_line;
810 ROOT_DEV = Root_RAM0;
812 init_mm.start_code = PAGE_OFFSET;
813 init_mm.end_code = (unsigned long) &_etext;
814 init_mm.end_data = (unsigned long) &_edata;
815 init_mm.brk = (unsigned long) &_end;
817 if (MACHINE_HAS_MVCOS)
818 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
820 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
826 setup_addressing_mode();
832 __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
833 s390_init_cpu_topology();
836 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
841 * Create kernel page tables and switch to virtual addressing.
845 /* Setup default console */
848 /* Setup zfcpdump support */
849 setup_zfcpdump(console_devno);