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>
45 #include <linux/ftrace.h>
48 #include <asm/uaccess.h>
49 #include <asm/system.h>
51 #include <asm/mmu_context.h>
52 #include <asm/cpcmd.h>
53 #include <asm/lowcore.h>
56 #include <asm/ptrace.h>
57 #include <asm/sections.h>
58 #include <asm/ebcdic.h>
59 #include <asm/compat.h>
60 #include <asm/kvm_virtio.h>
62 long psw_kernel_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
63 PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
64 long psw_user_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
65 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
66 PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
69 * User copy operations.
71 struct uaccess_ops uaccess;
72 EXPORT_SYMBOL(uaccess);
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 = 0;
87 char elf_platform[ELF_PLATFORM_SIZE];
89 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
91 int __initdata memory_end_set;
92 unsigned long __initdata memory_end;
94 /* An array with a pointer to the lowcore of every CPU. */
95 struct _lowcore *lowcore_ptr[NR_CPUS];
96 EXPORT_SYMBOL(lowcore_ptr);
99 * This is set up by the setup-routine at boot-time
100 * for S390 need to find out, what we have to setup
101 * using address 0x10400 ...
104 #include <asm/setup.h>
106 static struct resource code_resource = {
107 .name = "Kernel code",
108 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
111 static struct resource data_resource = {
112 .name = "Kernel data",
113 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
117 * cpu_init() initializes state that is per-CPU.
119 void __cpuinit cpu_init(void)
122 * Store processor id in lowcore (used e.g. in timer_interrupt)
124 get_cpu_id(&S390_lowcore.cpu_id);
126 atomic_inc(&init_mm.mm_count);
127 current->active_mm = &init_mm;
129 enter_lazy_tlb(&init_mm, current);
133 * condev= and conmode= setup parameter.
136 static int __init condev_setup(char *str)
140 vdev = simple_strtoul(str, &str, 0);
141 if (vdev >= 0 && vdev < 65536) {
142 console_devno = vdev;
148 __setup("condev=", condev_setup);
150 static void __init set_preferred_console(void)
153 add_preferred_console("hvc", 0, NULL);
154 else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
155 add_preferred_console("ttyS", 0, NULL);
156 else if (CONSOLE_IS_3270)
157 add_preferred_console("tty3270", 0, NULL);
160 static int __init conmode_setup(char *str)
162 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
163 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
166 #if defined(CONFIG_TN3215_CONSOLE)
167 if (strncmp(str, "3215", 5) == 0)
170 #if defined(CONFIG_TN3270_CONSOLE)
171 if (strncmp(str, "3270", 5) == 0)
174 set_preferred_console();
178 __setup("conmode=", conmode_setup);
180 static void __init conmode_default(void)
182 char query_buffer[1024];
186 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
187 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
188 ptr = strstr(query_buffer, "SUBCHANNEL =");
189 console_irq = simple_strtoul(ptr + 13, NULL, 16);
190 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
191 ptr = strstr(query_buffer, "CONMODE");
193 * Set the conmode to 3215 so that the device recognition
194 * will set the cu_type of the console to 3215. If the
195 * conmode is 3270 and we don't set it back then both
196 * 3215 and the 3270 driver will try to access the console
197 * device (3215 as console and 3270 as normal tty).
199 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
201 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
206 if (strncmp(ptr + 8, "3270", 4) == 0) {
207 #if defined(CONFIG_TN3270_CONSOLE)
209 #elif defined(CONFIG_TN3215_CONSOLE)
211 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
214 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
215 #if defined(CONFIG_TN3215_CONSOLE)
217 #elif defined(CONFIG_TN3270_CONSOLE)
219 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
224 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
230 #ifdef CONFIG_ZFCPDUMP
231 static void __init setup_zfcpdump(unsigned int console_devno)
235 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
237 if (console_devno != -1)
238 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
239 ipl_info.data.fcp.dev_id.devno, console_devno);
241 sprintf(str, " cio_ignore=all,!0.0.%04x",
242 ipl_info.data.fcp.dev_id.devno);
243 strcat(boot_command_line, str);
244 console_loglevel = 2;
247 static inline void setup_zfcpdump(unsigned int console_devno) {}
248 #endif /* CONFIG_ZFCPDUMP */
251 * Reboot, halt and power_off stubs. They just call _machine_restart,
252 * _machine_halt or _machine_power_off.
255 void machine_restart(char *command)
257 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
259 * Only unblank the console if we are called in enabled
260 * context or a bust_spinlocks cleared the way for us.
263 _machine_restart(command);
266 void machine_halt(void)
268 if (!in_interrupt() || oops_in_progress)
270 * Only unblank the console if we are called in enabled
271 * context or a bust_spinlocks cleared the way for us.
277 void machine_power_off(void)
279 if (!in_interrupt() || oops_in_progress)
281 * Only unblank the console if we are called in enabled
282 * context or a bust_spinlocks cleared the way for us.
285 _machine_power_off();
289 * Dummy power off function.
291 void (*pm_power_off)(void) = machine_power_off;
293 static int __init early_parse_mem(char *p)
295 memory_end = memparse(p, &p);
299 early_param("mem", early_parse_mem);
301 unsigned int user_mode = HOME_SPACE_MODE;
302 EXPORT_SYMBOL_GPL(user_mode);
304 static int set_amode_and_uaccess(unsigned long user_amode,
305 unsigned long user32_amode)
307 psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
308 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
309 PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
311 psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
312 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
313 PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
314 psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
315 PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
318 psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
319 PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
321 if (MACHINE_HAS_MVCOS) {
322 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
325 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
331 * Switch kernel/user addressing modes?
333 static int __init early_parse_switch_amode(char *p)
335 if (user_mode != SECONDARY_SPACE_MODE)
336 user_mode = PRIMARY_SPACE_MODE;
339 early_param("switch_amode", early_parse_switch_amode);
341 static int __init early_parse_user_mode(char *p)
343 if (p && strcmp(p, "primary") == 0)
344 user_mode = PRIMARY_SPACE_MODE;
345 #ifdef CONFIG_S390_EXEC_PROTECT
346 else if (p && strcmp(p, "secondary") == 0)
347 user_mode = SECONDARY_SPACE_MODE;
349 else if (!p || strcmp(p, "home") == 0)
350 user_mode = HOME_SPACE_MODE;
355 early_param("user_mode", early_parse_user_mode);
357 #ifdef CONFIG_S390_EXEC_PROTECT
359 * Enable execute protection?
361 static int __init early_parse_noexec(char *p)
363 if (!strncmp(p, "off", 3))
365 user_mode = SECONDARY_SPACE_MODE;
368 early_param("noexec", early_parse_noexec);
369 #endif /* CONFIG_S390_EXEC_PROTECT */
371 static void setup_addressing_mode(void)
373 if (user_mode == SECONDARY_SPACE_MODE) {
374 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
375 PSW32_ASC_SECONDARY))
376 pr_info("Execute protection active, "
377 "mvcos available\n");
379 pr_info("Execute protection active, "
380 "mvcos not available\n");
381 } else if (user_mode == PRIMARY_SPACE_MODE) {
382 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
383 pr_info("Address spaces switched, "
384 "mvcos available\n");
386 pr_info("Address spaces switched, "
387 "mvcos not available\n");
389 #ifdef CONFIG_TRACE_IRQFLAGS
390 sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
391 io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
402 * Setup lowcore for boot cpu
404 lc_pages = sizeof(void *) == 8 ? 2 : 1;
405 lc = (struct _lowcore *)
406 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
407 memset(lc, 0, lc_pages * PAGE_SIZE);
408 lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
409 lc->restart_psw.addr =
410 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
411 if (user_mode != HOME_SPACE_MODE)
412 lc->restart_psw.mask |= PSW_ASC_HOME;
413 lc->external_new_psw.mask = psw_kernel_bits;
414 lc->external_new_psw.addr =
415 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
416 lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
417 lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
418 lc->program_new_psw.mask = psw_kernel_bits;
419 lc->program_new_psw.addr =
420 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
421 lc->mcck_new_psw.mask =
422 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
423 lc->mcck_new_psw.addr =
424 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
425 lc->io_new_psw.mask = psw_kernel_bits;
426 lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
427 lc->clock_comparator = -1ULL;
428 lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
429 lc->async_stack = (unsigned long)
430 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
431 lc->panic_stack = (unsigned long)
432 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
433 lc->current_task = (unsigned long) init_thread_union.thread_info.task;
434 lc->thread_info = (unsigned long) &init_thread_union;
435 lc->machine_flags = S390_lowcore.machine_flags;
437 if (MACHINE_HAS_IEEE) {
438 lc->extended_save_area_addr = (__u32)
439 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
440 /* enable extended save area */
441 __ctl_set_bit(14, 29);
444 lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
446 lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
447 lc->async_enter_timer = S390_lowcore.async_enter_timer;
448 lc->exit_timer = S390_lowcore.exit_timer;
449 lc->user_timer = S390_lowcore.user_timer;
450 lc->system_timer = S390_lowcore.system_timer;
451 lc->steal_timer = S390_lowcore.steal_timer;
452 lc->last_update_timer = S390_lowcore.last_update_timer;
453 lc->last_update_clock = S390_lowcore.last_update_clock;
454 lc->ftrace_func = S390_lowcore.ftrace_func;
455 set_prefix((u32)(unsigned long) lc);
460 setup_resources(void)
462 struct resource *res, *sub_res;
465 code_resource.start = (unsigned long) &_text;
466 code_resource.end = (unsigned long) &_etext - 1;
467 data_resource.start = (unsigned long) &_etext;
468 data_resource.end = (unsigned long) &_edata - 1;
470 for (i = 0; i < MEMORY_CHUNKS; i++) {
471 if (!memory_chunk[i].size)
473 res = alloc_bootmem_low(sizeof(struct resource));
474 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
475 switch (memory_chunk[i].type) {
476 case CHUNK_READ_WRITE:
477 res->name = "System RAM";
479 case CHUNK_READ_ONLY:
480 res->name = "System ROM";
481 res->flags |= IORESOURCE_READONLY;
484 res->name = "reserved";
486 res->start = memory_chunk[i].addr;
487 res->end = memory_chunk[i].addr + memory_chunk[i].size - 1;
488 request_resource(&iomem_resource, res);
490 if (code_resource.start >= res->start &&
491 code_resource.start <= res->end &&
492 code_resource.end > res->end) {
493 sub_res = alloc_bootmem_low(sizeof(struct resource));
494 memcpy(sub_res, &code_resource,
495 sizeof(struct resource));
496 sub_res->end = res->end;
497 code_resource.start = res->end + 1;
498 request_resource(res, sub_res);
501 if (code_resource.start >= res->start &&
502 code_resource.start <= res->end &&
503 code_resource.end <= res->end)
504 request_resource(res, &code_resource);
506 if (data_resource.start >= res->start &&
507 data_resource.start <= res->end &&
508 data_resource.end > res->end) {
509 sub_res = alloc_bootmem_low(sizeof(struct resource));
510 memcpy(sub_res, &data_resource,
511 sizeof(struct resource));
512 sub_res->end = res->end;
513 data_resource.start = res->end + 1;
514 request_resource(res, sub_res);
517 if (data_resource.start >= res->start &&
518 data_resource.start <= res->end &&
519 data_resource.end <= res->end)
520 request_resource(res, &data_resource);
524 unsigned long real_memory_size;
525 EXPORT_SYMBOL_GPL(real_memory_size);
527 static void __init setup_memory_end(void)
529 unsigned long memory_size;
530 unsigned long max_mem;
533 #ifdef CONFIG_ZFCPDUMP
534 if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
535 memory_end = ZFCPDUMP_HSA_SIZE;
540 memory_end &= PAGE_MASK;
542 max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
543 memory_end = min(max_mem, memory_end);
546 * Make sure all chunks are MAX_ORDER aligned so we don't need the
547 * extra checks that HOLES_IN_ZONE would require.
549 for (i = 0; i < MEMORY_CHUNKS; i++) {
550 unsigned long start, end;
551 struct mem_chunk *chunk;
554 chunk = &memory_chunk[i];
555 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
556 start = (chunk->addr + align - 1) & ~(align - 1);
557 end = (chunk->addr + chunk->size) & ~(align - 1);
559 memset(chunk, 0, sizeof(*chunk));
562 chunk->size = end - start;
566 for (i = 0; i < MEMORY_CHUNKS; i++) {
567 struct mem_chunk *chunk = &memory_chunk[i];
569 real_memory_size = max(real_memory_size,
570 chunk->addr + chunk->size);
571 if (chunk->addr >= max_mem) {
572 memset(chunk, 0, sizeof(*chunk));
575 if (chunk->addr + chunk->size > max_mem)
576 chunk->size = max_mem - chunk->addr;
577 memory_size = max(memory_size, chunk->addr + chunk->size);
580 memory_end = memory_size;
586 unsigned long bootmap_size;
587 unsigned long start_pfn, end_pfn;
591 * partially used pages are not usable - thus
592 * we are rounding upwards:
594 start_pfn = PFN_UP(__pa(&_end));
595 end_pfn = max_pfn = PFN_DOWN(memory_end);
597 #ifdef CONFIG_BLK_DEV_INITRD
599 * Move the initrd in case the bitmap of the bootmem allocater
600 * would overwrite it.
603 if (INITRD_START && INITRD_SIZE) {
604 unsigned long bmap_size;
607 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
608 bmap_size = PFN_PHYS(bmap_size);
610 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
611 start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
613 if (start + INITRD_SIZE > memory_end) {
614 pr_err("initrd extends beyond end of "
615 "memory (0x%08lx > 0x%08lx) "
616 "disabling initrd\n",
617 start + INITRD_SIZE, memory_end);
618 INITRD_START = INITRD_SIZE = 0;
620 pr_info("Moving initrd (0x%08lx -> "
621 "0x%08lx, size: %ld)\n",
622 INITRD_START, start, INITRD_SIZE);
623 memmove((void *) start, (void *) INITRD_START,
625 INITRD_START = start;
632 * Initialize the boot-time allocator
634 bootmap_size = init_bootmem(start_pfn, end_pfn);
637 * Register RAM areas with the bootmem allocator.
640 for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
641 unsigned long start_chunk, end_chunk, pfn;
643 if (memory_chunk[i].type != CHUNK_READ_WRITE)
645 start_chunk = PFN_DOWN(memory_chunk[i].addr);
646 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
647 end_chunk = min(end_chunk, end_pfn);
648 if (start_chunk >= end_chunk)
650 add_active_range(0, start_chunk, end_chunk);
651 pfn = max(start_chunk, start_pfn);
652 for (; pfn < end_chunk; pfn++)
653 page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
656 psw_set_key(PAGE_DEFAULT_KEY);
658 free_bootmem_with_active_regions(0, max_pfn);
661 * Reserve memory used for lowcore/command line/kernel image.
663 reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
664 reserve_bootmem((unsigned long)_stext,
665 PFN_PHYS(start_pfn) - (unsigned long)_stext,
668 * Reserve the bootmem bitmap itself as well. We do this in two
669 * steps (first step was init_bootmem()) because this catches
670 * the (very unlikely) case of us accidentally initializing the
671 * bootmem allocator with an invalid RAM area.
673 reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
676 #ifdef CONFIG_BLK_DEV_INITRD
677 if (INITRD_START && INITRD_SIZE) {
678 if (INITRD_START + INITRD_SIZE <= memory_end) {
679 reserve_bootmem(INITRD_START, INITRD_SIZE,
681 initrd_start = INITRD_START;
682 initrd_end = initrd_start + INITRD_SIZE;
684 pr_err("initrd extends beyond end of "
685 "memory (0x%08lx > 0x%08lx) "
686 "disabling initrd\n",
687 initrd_start + INITRD_SIZE, memory_end);
688 initrd_start = initrd_end = 0;
695 * Setup hardware capabilities.
697 static void __init setup_hwcaps(void)
699 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
700 unsigned long long facility_list_extended;
701 unsigned int facility_list;
704 facility_list = stfl();
706 * The store facility list bits numbers as found in the principles
707 * of operation are numbered with bit 1UL<<31 as number 0 to
708 * bit 1UL<<0 as number 31.
709 * Bit 0: instructions named N3, "backported" to esa-mode
710 * Bit 2: z/Architecture mode is active
711 * Bit 7: the store-facility-list-extended facility is installed
712 * Bit 17: the message-security assist is installed
713 * Bit 19: the long-displacement facility is installed
714 * Bit 21: the extended-immediate facility is installed
715 * Bit 22: extended-translation facility 3 is installed
716 * Bit 30: extended-translation facility 3 enhancement facility
717 * These get translated to:
718 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
719 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
720 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
721 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
723 for (i = 0; i < 6; i++)
724 if (facility_list & (1UL << (31 - stfl_bits[i])))
725 elf_hwcap |= 1UL << i;
727 if ((facility_list & (1UL << (31 - 22)))
728 && (facility_list & (1UL << (31 - 30))))
729 elf_hwcap |= HWCAP_S390_ETF3EH;
732 * Check for additional facilities with store-facility-list-extended.
733 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
734 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
735 * as stored by stfl, bits 32-xxx contain additional facilities.
736 * How many facility words are stored depends on the number of
737 * doublewords passed to the instruction. The additional facilites
739 * Bit 42: decimal floating point facility is installed
740 * Bit 44: perform floating point operation facility is installed
742 * HWCAP_S390_DFP bit 6 (42 && 44).
744 if ((elf_hwcap & (1UL << 2)) &&
745 __stfle(&facility_list_extended, 1) > 0) {
746 if ((facility_list_extended & (1ULL << (63 - 42)))
747 && (facility_list_extended & (1ULL << (63 - 44))))
748 elf_hwcap |= HWCAP_S390_DFP;
752 * Huge page support HWCAP_S390_HPAGE is bit 7.
754 if (MACHINE_HAS_HPAGE)
755 elf_hwcap |= HWCAP_S390_HPAGE;
758 * 64-bit register support for 31-bit processes
759 * HWCAP_S390_HIGH_GPRS is bit 9.
761 elf_hwcap |= HWCAP_S390_HIGH_GPRS;
763 switch (S390_lowcore.cpu_id.machine) {
765 #if !defined(CONFIG_64BIT)
766 default: /* Use "g5" as default for 31 bit kernels. */
768 strcpy(elf_platform, "g5");
772 #if defined(CONFIG_64BIT)
773 default: /* Use "z900" as default for 64 bit kernels. */
775 strcpy(elf_platform, "z900");
779 strcpy(elf_platform, "z990");
783 strcpy(elf_platform, "z9-109");
787 strcpy(elf_platform, "z10");
793 * Setup function called from init/main.c just after the banner
798 setup_arch(char **cmdline_p)
801 * print what head.S has found out about the machine
805 pr_info("Linux is running as a z/VM "
806 "guest operating system in 31-bit mode\n");
808 pr_info("Linux is running natively in 31-bit mode\n");
809 if (MACHINE_HAS_IEEE)
810 pr_info("The hardware system has IEEE compatible "
811 "floating point units\n");
813 pr_info("The hardware system has no IEEE compatible "
814 "floating point units\n");
815 #else /* CONFIG_64BIT */
817 pr_info("Linux is running as a z/VM "
818 "guest operating system in 64-bit mode\n");
819 else if (MACHINE_IS_KVM)
820 pr_info("Linux is running under KVM in 64-bit mode\n");
822 pr_info("Linux is running natively in 64-bit mode\n");
823 #endif /* CONFIG_64BIT */
825 /* Have one command line that is parsed and saved in /proc/cmdline */
826 /* boot_command_line has been already set up in early.c */
827 *cmdline_p = boot_command_line;
829 ROOT_DEV = Root_RAM0;
831 init_mm.start_code = PAGE_OFFSET;
832 init_mm.end_code = (unsigned long) &_etext;
833 init_mm.end_data = (unsigned long) &_edata;
834 init_mm.brk = (unsigned long) &_end;
836 if (MACHINE_HAS_MVCOS)
837 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
839 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
845 setup_addressing_mode();
851 s390_init_cpu_topology();
854 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
859 * Create kernel page tables and switch to virtual addressing.
863 /* Setup default console */
865 set_preferred_console();
867 /* Setup zfcpdump support */
868 setup_zfcpdump(console_devno);