fed up with those stupid warnings
[mmotm.git] / arch / s390 / kernel / setup.c
blob0663287fa1b30f2c45d5cb24da59acf15608e914
1 /*
2 * arch/s390/kernel/setup.c
4 * S390 version
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>
24 #include <linux/mm.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>
47 #include <asm/ipl.h>
48 #include <asm/uaccess.h>
49 #include <asm/system.h>
50 #include <asm/smp.h>
51 #include <asm/mmu_context.h>
52 #include <asm/cpcmd.h>
53 #include <asm/lowcore.h>
54 #include <asm/irq.h>
55 #include <asm/page.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);
75 * Machine setup..
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];
90 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
92 int __initdata memory_end_set;
93 unsigned long __initdata memory_end;
95 /* An array with a pointer to the lowcore of every CPU. */
96 struct _lowcore *lowcore_ptr[NR_CPUS];
97 EXPORT_SYMBOL(lowcore_ptr);
100 * This is set up by the setup-routine at boot-time
101 * for S390 need to find out, what we have to setup
102 * using address 0x10400 ...
105 #include <asm/setup.h>
107 static struct resource code_resource = {
108 .name = "Kernel code",
109 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
112 static struct resource data_resource = {
113 .name = "Kernel data",
114 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
118 * cpu_init() initializes state that is per-CPU.
120 void __cpuinit cpu_init(void)
123 * Store processor id in lowcore (used e.g. in timer_interrupt)
125 get_cpu_id(&S390_lowcore.cpu_id);
128 * Force FPU initialization:
130 clear_thread_flag(TIF_USEDFPU);
131 clear_used_math();
133 atomic_inc(&init_mm.mm_count);
134 current->active_mm = &init_mm;
135 BUG_ON(current->mm);
136 enter_lazy_tlb(&init_mm, current);
140 * condev= and conmode= setup parameter.
143 static int __init condev_setup(char *str)
145 int vdev;
147 vdev = simple_strtoul(str, &str, 0);
148 if (vdev >= 0 && vdev < 65536) {
149 console_devno = vdev;
150 console_irq = -1;
152 return 1;
155 __setup("condev=", condev_setup);
157 static void __init set_preferred_console(void)
159 if (MACHINE_IS_KVM)
160 add_preferred_console("hvc", 0, NULL);
161 else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
162 add_preferred_console("ttyS", 0, NULL);
163 else if (CONSOLE_IS_3270)
164 add_preferred_console("tty3270", 0, NULL);
167 static int __init conmode_setup(char *str)
169 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
170 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
171 SET_CONSOLE_SCLP;
172 #endif
173 #if defined(CONFIG_TN3215_CONSOLE)
174 if (strncmp(str, "3215", 5) == 0)
175 SET_CONSOLE_3215;
176 #endif
177 #if defined(CONFIG_TN3270_CONSOLE)
178 if (strncmp(str, "3270", 5) == 0)
179 SET_CONSOLE_3270;
180 #endif
181 set_preferred_console();
182 return 1;
185 __setup("conmode=", conmode_setup);
187 static void __init conmode_default(void)
189 char query_buffer[1024];
190 char *ptr;
192 if (MACHINE_IS_VM) {
193 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
194 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
195 ptr = strstr(query_buffer, "SUBCHANNEL =");
196 console_irq = simple_strtoul(ptr + 13, NULL, 16);
197 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
198 ptr = strstr(query_buffer, "CONMODE");
200 * Set the conmode to 3215 so that the device recognition
201 * will set the cu_type of the console to 3215. If the
202 * conmode is 3270 and we don't set it back then both
203 * 3215 and the 3270 driver will try to access the console
204 * device (3215 as console and 3270 as normal tty).
206 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
207 if (ptr == NULL) {
208 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
209 SET_CONSOLE_SCLP;
210 #endif
211 return;
213 if (strncmp(ptr + 8, "3270", 4) == 0) {
214 #if defined(CONFIG_TN3270_CONSOLE)
215 SET_CONSOLE_3270;
216 #elif defined(CONFIG_TN3215_CONSOLE)
217 SET_CONSOLE_3215;
218 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
219 SET_CONSOLE_SCLP;
220 #endif
221 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
222 #if defined(CONFIG_TN3215_CONSOLE)
223 SET_CONSOLE_3215;
224 #elif defined(CONFIG_TN3270_CONSOLE)
225 SET_CONSOLE_3270;
226 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
227 SET_CONSOLE_SCLP;
228 #endif
230 } else {
231 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
232 SET_CONSOLE_SCLP;
233 #endif
237 #ifdef CONFIG_ZFCPDUMP
238 static void __init setup_zfcpdump(unsigned int console_devno)
240 static char str[41];
242 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
243 return;
244 if (console_devno != -1)
245 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
246 ipl_info.data.fcp.dev_id.devno, console_devno);
247 else
248 sprintf(str, " cio_ignore=all,!0.0.%04x",
249 ipl_info.data.fcp.dev_id.devno);
250 strcat(boot_command_line, str);
251 console_loglevel = 2;
253 #else
254 static inline void setup_zfcpdump(unsigned int console_devno) {}
255 #endif /* CONFIG_ZFCPDUMP */
258 * Reboot, halt and power_off stubs. They just call _machine_restart,
259 * _machine_halt or _machine_power_off.
262 void machine_restart(char *command)
264 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
266 * Only unblank the console if we are called in enabled
267 * context or a bust_spinlocks cleared the way for us.
269 console_unblank();
270 _machine_restart(command);
273 void machine_halt(void)
275 if (!in_interrupt() || oops_in_progress)
277 * Only unblank the console if we are called in enabled
278 * context or a bust_spinlocks cleared the way for us.
280 console_unblank();
281 _machine_halt();
284 void machine_power_off(void)
286 if (!in_interrupt() || oops_in_progress)
288 * Only unblank the console if we are called in enabled
289 * context or a bust_spinlocks cleared the way for us.
291 console_unblank();
292 _machine_power_off();
296 * Dummy power off function.
298 void (*pm_power_off)(void) = machine_power_off;
300 static int __init early_parse_mem(char *p)
302 memory_end = memparse(p, &p);
303 memory_end_set = 1;
304 return 0;
306 early_param("mem", early_parse_mem);
308 unsigned int user_mode = HOME_SPACE_MODE;
309 EXPORT_SYMBOL_GPL(user_mode);
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;
317 #ifdef CONFIG_COMPAT
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 |
323 PSW32_MASK_PSTATE;
324 #endif
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));
330 return 1;
331 } else {
332 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
333 return 0;
338 * Switch kernel/user addressing modes?
340 static int __init early_parse_switch_amode(char *p)
342 if (user_mode != SECONDARY_SPACE_MODE)
343 user_mode = PRIMARY_SPACE_MODE;
344 return 0;
346 early_param("switch_amode", early_parse_switch_amode);
348 static int __init early_parse_user_mode(char *p)
350 if (p && strcmp(p, "primary") == 0)
351 user_mode = PRIMARY_SPACE_MODE;
352 #ifdef CONFIG_S390_EXEC_PROTECT
353 else if (p && strcmp(p, "secondary") == 0)
354 user_mode = SECONDARY_SPACE_MODE;
355 #endif
356 else if (!p || strcmp(p, "home") == 0)
357 user_mode = HOME_SPACE_MODE;
358 else
359 return 1;
360 return 0;
362 early_param("user_mode", early_parse_user_mode);
364 #ifdef CONFIG_S390_EXEC_PROTECT
366 * Enable execute protection?
368 static int __init early_parse_noexec(char *p)
370 if (!strncmp(p, "off", 3))
371 return 0;
372 user_mode = SECONDARY_SPACE_MODE;
373 return 0;
375 early_param("noexec", early_parse_noexec);
376 #endif /* CONFIG_S390_EXEC_PROTECT */
378 static void setup_addressing_mode(void)
380 if (user_mode == SECONDARY_SPACE_MODE) {
381 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
382 PSW32_ASC_SECONDARY))
383 pr_info("Execute protection active, "
384 "mvcos available\n");
385 else
386 pr_info("Execute protection active, "
387 "mvcos not available\n");
388 } else if (user_mode == PRIMARY_SPACE_MODE) {
389 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
390 pr_info("Address spaces switched, "
391 "mvcos available\n");
392 else
393 pr_info("Address spaces switched, "
394 "mvcos not available\n");
396 #ifdef CONFIG_TRACE_IRQFLAGS
397 sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
398 io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
399 #endif
402 static void __init
403 setup_lowcore(void)
405 struct _lowcore *lc;
406 int lc_pages;
409 * Setup lowcore for boot cpu
411 lc_pages = sizeof(void *) == 8 ? 2 : 1;
412 lc = (struct _lowcore *)
413 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
414 memset(lc, 0, lc_pages * PAGE_SIZE);
415 lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
416 lc->restart_psw.addr =
417 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
418 if (user_mode != HOME_SPACE_MODE)
419 lc->restart_psw.mask |= PSW_ASC_HOME;
420 lc->external_new_psw.mask = psw_kernel_bits;
421 lc->external_new_psw.addr =
422 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
423 lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
424 lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
425 lc->program_new_psw.mask = psw_kernel_bits;
426 lc->program_new_psw.addr =
427 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
428 lc->mcck_new_psw.mask =
429 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
430 lc->mcck_new_psw.addr =
431 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
432 lc->io_new_psw.mask = psw_kernel_bits;
433 lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
434 lc->clock_comparator = -1ULL;
435 lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
436 lc->async_stack = (unsigned long)
437 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
438 lc->panic_stack = (unsigned long)
439 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
440 lc->current_task = (unsigned long) init_thread_union.thread_info.task;
441 lc->thread_info = (unsigned long) &init_thread_union;
442 lc->machine_flags = S390_lowcore.machine_flags;
443 #ifndef CONFIG_64BIT
444 if (MACHINE_HAS_IEEE) {
445 lc->extended_save_area_addr = (__u32)
446 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
447 /* enable extended save area */
448 __ctl_set_bit(14, 29);
450 #else
451 lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
452 #endif
453 lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
454 lc->async_enter_timer = S390_lowcore.async_enter_timer;
455 lc->exit_timer = S390_lowcore.exit_timer;
456 lc->user_timer = S390_lowcore.user_timer;
457 lc->system_timer = S390_lowcore.system_timer;
458 lc->steal_timer = S390_lowcore.steal_timer;
459 lc->last_update_timer = S390_lowcore.last_update_timer;
460 lc->last_update_clock = S390_lowcore.last_update_clock;
461 lc->ftrace_func = S390_lowcore.ftrace_func;
462 set_prefix((u32)(unsigned long) lc);
463 lowcore_ptr[0] = lc;
466 static void __init
467 setup_resources(void)
469 struct resource *res, *sub_res;
470 int i;
472 code_resource.start = (unsigned long) &_text;
473 code_resource.end = (unsigned long) &_etext - 1;
474 data_resource.start = (unsigned long) &_etext;
475 data_resource.end = (unsigned long) &_edata - 1;
477 for (i = 0; i < MEMORY_CHUNKS; i++) {
478 if (!memory_chunk[i].size)
479 continue;
480 res = alloc_bootmem_low(sizeof(struct resource));
481 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
482 switch (memory_chunk[i].type) {
483 case CHUNK_READ_WRITE:
484 res->name = "System RAM";
485 break;
486 case CHUNK_READ_ONLY:
487 res->name = "System ROM";
488 res->flags |= IORESOURCE_READONLY;
489 break;
490 default:
491 res->name = "reserved";
493 res->start = memory_chunk[i].addr;
494 res->end = memory_chunk[i].addr + memory_chunk[i].size - 1;
495 request_resource(&iomem_resource, res);
497 if (code_resource.start >= res->start &&
498 code_resource.start <= res->end &&
499 code_resource.end > res->end) {
500 sub_res = alloc_bootmem_low(sizeof(struct resource));
501 memcpy(sub_res, &code_resource,
502 sizeof(struct resource));
503 sub_res->end = res->end;
504 code_resource.start = res->end + 1;
505 request_resource(res, sub_res);
508 if (code_resource.start >= res->start &&
509 code_resource.start <= res->end &&
510 code_resource.end <= res->end)
511 request_resource(res, &code_resource);
513 if (data_resource.start >= res->start &&
514 data_resource.start <= res->end &&
515 data_resource.end > res->end) {
516 sub_res = alloc_bootmem_low(sizeof(struct resource));
517 memcpy(sub_res, &data_resource,
518 sizeof(struct resource));
519 sub_res->end = res->end;
520 data_resource.start = res->end + 1;
521 request_resource(res, sub_res);
524 if (data_resource.start >= res->start &&
525 data_resource.start <= res->end &&
526 data_resource.end <= res->end)
527 request_resource(res, &data_resource);
531 unsigned long real_memory_size;
532 EXPORT_SYMBOL_GPL(real_memory_size);
534 static void __init setup_memory_end(void)
536 unsigned long memory_size;
537 unsigned long max_mem;
538 int i;
540 #ifdef CONFIG_ZFCPDUMP
541 if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
542 memory_end = ZFCPDUMP_HSA_SIZE;
543 memory_end_set = 1;
545 #endif
546 memory_size = 0;
547 memory_end &= PAGE_MASK;
549 max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
550 memory_end = min(max_mem, memory_end);
553 * Make sure all chunks are MAX_ORDER aligned so we don't need the
554 * extra checks that HOLES_IN_ZONE would require.
556 for (i = 0; i < MEMORY_CHUNKS; i++) {
557 unsigned long start, end;
558 struct mem_chunk *chunk;
559 unsigned long align;
561 chunk = &memory_chunk[i];
562 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
563 start = (chunk->addr + align - 1) & ~(align - 1);
564 end = (chunk->addr + chunk->size) & ~(align - 1);
565 if (start >= end)
566 memset(chunk, 0, sizeof(*chunk));
567 else {
568 chunk->addr = start;
569 chunk->size = end - start;
573 for (i = 0; i < MEMORY_CHUNKS; i++) {
574 struct mem_chunk *chunk = &memory_chunk[i];
576 real_memory_size = max(real_memory_size,
577 chunk->addr + chunk->size);
578 if (chunk->addr >= max_mem) {
579 memset(chunk, 0, sizeof(*chunk));
580 continue;
582 if (chunk->addr + chunk->size > max_mem)
583 chunk->size = max_mem - chunk->addr;
584 memory_size = max(memory_size, chunk->addr + chunk->size);
586 if (!memory_end)
587 memory_end = memory_size;
590 static void __init
591 setup_memory(void)
593 unsigned long bootmap_size;
594 unsigned long start_pfn, end_pfn;
595 int i;
598 * partially used pages are not usable - thus
599 * we are rounding upwards:
601 start_pfn = PFN_UP(__pa(&_end));
602 end_pfn = max_pfn = PFN_DOWN(memory_end);
604 #ifdef CONFIG_BLK_DEV_INITRD
606 * Move the initrd in case the bitmap of the bootmem allocater
607 * would overwrite it.
610 if (INITRD_START && INITRD_SIZE) {
611 unsigned long bmap_size;
612 unsigned long start;
614 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
615 bmap_size = PFN_PHYS(bmap_size);
617 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
618 start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
620 if (start + INITRD_SIZE > memory_end) {
621 pr_err("initrd extends beyond end of "
622 "memory (0x%08lx > 0x%08lx) "
623 "disabling initrd\n",
624 start + INITRD_SIZE, memory_end);
625 INITRD_START = INITRD_SIZE = 0;
626 } else {
627 pr_info("Moving initrd (0x%08lx -> "
628 "0x%08lx, size: %ld)\n",
629 INITRD_START, start, INITRD_SIZE);
630 memmove((void *) start, (void *) INITRD_START,
631 INITRD_SIZE);
632 INITRD_START = start;
636 #endif
639 * Initialize the boot-time allocator
641 bootmap_size = init_bootmem(start_pfn, end_pfn);
644 * Register RAM areas with the bootmem allocator.
647 for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
648 unsigned long start_chunk, end_chunk, pfn;
650 if (memory_chunk[i].type != CHUNK_READ_WRITE)
651 continue;
652 start_chunk = PFN_DOWN(memory_chunk[i].addr);
653 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
654 end_chunk = min(end_chunk, end_pfn);
655 if (start_chunk >= end_chunk)
656 continue;
657 add_active_range(0, start_chunk, end_chunk);
658 pfn = max(start_chunk, start_pfn);
659 for (; pfn < end_chunk; pfn++)
660 page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
663 psw_set_key(PAGE_DEFAULT_KEY);
665 free_bootmem_with_active_regions(0, max_pfn);
668 * Reserve memory used for lowcore/command line/kernel image.
670 reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
671 reserve_bootmem((unsigned long)_stext,
672 PFN_PHYS(start_pfn) - (unsigned long)_stext,
673 BOOTMEM_DEFAULT);
675 * Reserve the bootmem bitmap itself as well. We do this in two
676 * steps (first step was init_bootmem()) because this catches
677 * the (very unlikely) case of us accidentally initializing the
678 * bootmem allocator with an invalid RAM area.
680 reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
681 BOOTMEM_DEFAULT);
683 #ifdef CONFIG_BLK_DEV_INITRD
684 if (INITRD_START && INITRD_SIZE) {
685 if (INITRD_START + INITRD_SIZE <= memory_end) {
686 reserve_bootmem(INITRD_START, INITRD_SIZE,
687 BOOTMEM_DEFAULT);
688 initrd_start = INITRD_START;
689 initrd_end = initrd_start + INITRD_SIZE;
690 } else {
691 pr_err("initrd extends beyond end of "
692 "memory (0x%08lx > 0x%08lx) "
693 "disabling initrd\n",
694 initrd_start + INITRD_SIZE, memory_end);
695 initrd_start = initrd_end = 0;
698 #endif
702 * Setup hardware capabilities.
704 static void __init setup_hwcaps(void)
706 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
707 unsigned long long facility_list_extended;
708 unsigned int facility_list;
709 int i;
711 facility_list = stfl();
713 * The store facility list bits numbers as found in the principles
714 * of operation are numbered with bit 1UL<<31 as number 0 to
715 * bit 1UL<<0 as number 31.
716 * Bit 0: instructions named N3, "backported" to esa-mode
717 * Bit 2: z/Architecture mode is active
718 * Bit 7: the store-facility-list-extended facility is installed
719 * Bit 17: the message-security assist is installed
720 * Bit 19: the long-displacement facility is installed
721 * Bit 21: the extended-immediate facility is installed
722 * Bit 22: extended-translation facility 3 is installed
723 * Bit 30: extended-translation facility 3 enhancement facility
724 * These get translated to:
725 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
726 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
727 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
728 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
730 for (i = 0; i < 6; i++)
731 if (facility_list & (1UL << (31 - stfl_bits[i])))
732 elf_hwcap |= 1UL << i;
734 if ((facility_list & (1UL << (31 - 22)))
735 && (facility_list & (1UL << (31 - 30))))
736 elf_hwcap |= HWCAP_S390_ETF3EH;
739 * Check for additional facilities with store-facility-list-extended.
740 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
741 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
742 * as stored by stfl, bits 32-xxx contain additional facilities.
743 * How many facility words are stored depends on the number of
744 * doublewords passed to the instruction. The additional facilites
745 * are:
746 * Bit 42: decimal floating point facility is installed
747 * Bit 44: perform floating point operation facility is installed
748 * translated to:
749 * HWCAP_S390_DFP bit 6 (42 && 44).
751 if ((elf_hwcap & (1UL << 2)) &&
752 __stfle(&facility_list_extended, 1) > 0) {
753 if ((facility_list_extended & (1ULL << (63 - 42)))
754 && (facility_list_extended & (1ULL << (63 - 44))))
755 elf_hwcap |= HWCAP_S390_DFP;
759 * Huge page support HWCAP_S390_HPAGE is bit 7.
761 if (MACHINE_HAS_HPAGE)
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;
770 switch (S390_lowcore.cpu_id.machine) {
771 case 0x9672:
772 #if !defined(CONFIG_64BIT)
773 default: /* Use "g5" as default for 31 bit kernels. */
774 #endif
775 strcpy(elf_platform, "g5");
776 break;
777 case 0x2064:
778 case 0x2066:
779 #if defined(CONFIG_64BIT)
780 default: /* Use "z900" as default for 64 bit kernels. */
781 #endif
782 strcpy(elf_platform, "z900");
783 break;
784 case 0x2084:
785 case 0x2086:
786 strcpy(elf_platform, "z990");
787 break;
788 case 0x2094:
789 case 0x2096:
790 strcpy(elf_platform, "z9-109");
791 break;
792 case 0x2097:
793 case 0x2098:
794 strcpy(elf_platform, "z10");
795 break;
800 * Setup function called from init/main.c just after the banner
801 * was printed.
804 void __init
805 setup_arch(char **cmdline_p)
808 * print what head.S has found out about the machine
810 #ifndef CONFIG_64BIT
811 if (MACHINE_IS_VM)
812 pr_info("Linux is running as a z/VM "
813 "guest operating system in 31-bit mode\n");
814 else
815 pr_info("Linux is running natively in 31-bit mode\n");
816 if (MACHINE_HAS_IEEE)
817 pr_info("The hardware system has IEEE compatible "
818 "floating point units\n");
819 else
820 pr_info("The hardware system has no IEEE compatible "
821 "floating point units\n");
822 #else /* CONFIG_64BIT */
823 if (MACHINE_IS_VM)
824 pr_info("Linux is running as a z/VM "
825 "guest operating system in 64-bit mode\n");
826 else if (MACHINE_IS_KVM)
827 pr_info("Linux is running under KVM in 64-bit mode\n");
828 else
829 pr_info("Linux is running natively in 64-bit mode\n");
830 #endif /* CONFIG_64BIT */
832 /* Have one command line that is parsed and saved in /proc/cmdline */
833 /* boot_command_line has been already set up in early.c */
834 *cmdline_p = boot_command_line;
836 ROOT_DEV = Root_RAM0;
838 init_mm.start_code = PAGE_OFFSET;
839 init_mm.end_code = (unsigned long) &_etext;
840 init_mm.end_data = (unsigned long) &_edata;
841 init_mm.brk = (unsigned long) &_end;
843 if (MACHINE_HAS_MVCOS)
844 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
845 else
846 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
848 parse_early_param();
850 setup_ipl();
851 setup_memory_end();
852 setup_addressing_mode();
853 setup_memory();
854 setup_resources();
855 setup_lowcore();
857 cpu_init();
858 __cpu_logical_map[0] = stap();
859 s390_init_cpu_topology();
862 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
864 setup_hwcaps();
867 * Create kernel page tables and switch to virtual addressing.
869 paging_init();
871 /* Setup default console */
872 conmode_default();
873 set_preferred_console();
875 /* Setup zfcpdump support */
876 setup_zfcpdump(console_devno);