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1/*
2 *  arch/s390/kernel/setup.c
3 *
4 *  S390 version
5 *    Copyright (C) IBM Corp. 1999,2010
6 *    Author(s): Hartmut Penner (hp@de.ibm.com),
7 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8 *
9 *  Derived from "arch/i386/kernel/setup.c"
10 *    Copyright (C) 1995, Linus Torvalds
11 */
12
13/*
14 * This file handles the architecture-dependent parts of initialization
15 */
16
17#define KMSG_COMPONENT "setup"
18#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
19
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/user.h>
29#include <linux/tty.h>
30#include <linux/ioport.h>
31#include <linux/delay.h>
32#include <linux/init.h>
33#include <linux/initrd.h>
34#include <linux/bootmem.h>
35#include <linux/root_dev.h>
36#include <linux/console.h>
37#include <linux/kernel_stat.h>
38#include <linux/device.h>
39#include <linux/notifier.h>
40#include <linux/pfn.h>
41#include <linux/ctype.h>
42#include <linux/reboot.h>
43#include <linux/topology.h>
44#include <linux/ftrace.h>
45
46#include <asm/ipl.h>
47#include <asm/uaccess.h>
48#include <asm/system.h>
49#include <asm/smp.h>
50#include <asm/mmu_context.h>
51#include <asm/cpcmd.h>
52#include <asm/lowcore.h>
53#include <asm/irq.h>
54#include <asm/page.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>
60
61long psw_kernel_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
62			   PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
63long 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);
66
67/*
68 * User copy operations.
69 */
70struct uaccess_ops uaccess;
71EXPORT_SYMBOL(uaccess);
72
73/*
74 * Machine setup..
75 */
76unsigned int console_mode = 0;
77EXPORT_SYMBOL(console_mode);
78
79unsigned int console_devno = -1;
80EXPORT_SYMBOL(console_devno);
81
82unsigned int console_irq = -1;
83EXPORT_SYMBOL(console_irq);
84
85unsigned long elf_hwcap = 0;
86char elf_platform[ELF_PLATFORM_SIZE];
87
88struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
89
90int __initdata memory_end_set;
91unsigned long __initdata memory_end;
92
93/* An array with a pointer to the lowcore of every CPU. */
94struct _lowcore *lowcore_ptr[NR_CPUS];
95EXPORT_SYMBOL(lowcore_ptr);
96
97/*
98 * This is set up by the setup-routine at boot-time
99 * for S390 need to find out, what we have to setup
100 * using address 0x10400 ...
101 */
102
103#include <asm/setup.h>
104
105static struct resource code_resource = {
106	.name  = "Kernel code",
107	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
108};
109
110static struct resource data_resource = {
111	.name = "Kernel data",
112	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
113};
114
115/*
116 * condev= and conmode= setup parameter.
117 */
118
119static int __init condev_setup(char *str)
120{
121	int vdev;
122
123	vdev = simple_strtoul(str, &str, 0);
124	if (vdev >= 0 && vdev < 65536) {
125		console_devno = vdev;
126		console_irq = -1;
127	}
128	return 1;
129}
130
131__setup("condev=", condev_setup);
132
133static void __init set_preferred_console(void)
134{
135	if (MACHINE_IS_KVM)
136		add_preferred_console("hvc", 0, NULL);
137	else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
138		add_preferred_console("ttyS", 0, NULL);
139	else if (CONSOLE_IS_3270)
140		add_preferred_console("tty3270", 0, NULL);
141}
142
143static int __init conmode_setup(char *str)
144{
145#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
146	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
147                SET_CONSOLE_SCLP;
148#endif
149#if defined(CONFIG_TN3215_CONSOLE)
150	if (strncmp(str, "3215", 5) == 0)
151		SET_CONSOLE_3215;
152#endif
153#if defined(CONFIG_TN3270_CONSOLE)
154	if (strncmp(str, "3270", 5) == 0)
155		SET_CONSOLE_3270;
156#endif
157	set_preferred_console();
158        return 1;
159}
160
161__setup("conmode=", conmode_setup);
162
163static void __init conmode_default(void)
164{
165	char query_buffer[1024];
166	char *ptr;
167
168        if (MACHINE_IS_VM) {
169		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
170		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
171		ptr = strstr(query_buffer, "SUBCHANNEL =");
172		console_irq = simple_strtoul(ptr + 13, NULL, 16);
173		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
174		ptr = strstr(query_buffer, "CONMODE");
175		/*
176		 * Set the conmode to 3215 so that the device recognition
177		 * will set the cu_type of the console to 3215. If the
178		 * conmode is 3270 and we don't set it back then both
179		 * 3215 and the 3270 driver will try to access the console
180		 * device (3215 as console and 3270 as normal tty).
181		 */
182		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
183		if (ptr == NULL) {
184#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
185			SET_CONSOLE_SCLP;
186#endif
187			return;
188		}
189		if (strncmp(ptr + 8, "3270", 4) == 0) {
190#if defined(CONFIG_TN3270_CONSOLE)
191			SET_CONSOLE_3270;
192#elif defined(CONFIG_TN3215_CONSOLE)
193			SET_CONSOLE_3215;
194#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
195			SET_CONSOLE_SCLP;
196#endif
197		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
198#if defined(CONFIG_TN3215_CONSOLE)
199			SET_CONSOLE_3215;
200#elif defined(CONFIG_TN3270_CONSOLE)
201			SET_CONSOLE_3270;
202#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
203			SET_CONSOLE_SCLP;
204#endif
205		}
206	} else {
207#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208		SET_CONSOLE_SCLP;
209#endif
210	}
211}
212
213#ifdef CONFIG_ZFCPDUMP
214static void __init setup_zfcpdump(unsigned int console_devno)
215{
216	static char str[41];
217
218	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
219		return;
220	if (console_devno != -1)
221		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
222			ipl_info.data.fcp.dev_id.devno, console_devno);
223	else
224		sprintf(str, " cio_ignore=all,!0.0.%04x",
225			ipl_info.data.fcp.dev_id.devno);
226	strcat(boot_command_line, str);
227	console_loglevel = 2;
228}
229#else
230static inline void setup_zfcpdump(unsigned int console_devno) {}
231#endif /* CONFIG_ZFCPDUMP */
232
233 /*
234 * Reboot, halt and power_off stubs. They just call _machine_restart,
235 * _machine_halt or _machine_power_off.
236 */
237
238void machine_restart(char *command)
239{
240	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
241		/*
242		 * Only unblank the console if we are called in enabled
243		 * context or a bust_spinlocks cleared the way for us.
244		 */
245		console_unblank();
246	_machine_restart(command);
247}
248
249void machine_halt(void)
250{
251	if (!in_interrupt() || oops_in_progress)
252		/*
253		 * Only unblank the console if we are called in enabled
254		 * context or a bust_spinlocks cleared the way for us.
255		 */
256		console_unblank();
257	_machine_halt();
258}
259
260void machine_power_off(void)
261{
262	if (!in_interrupt() || oops_in_progress)
263		/*
264		 * Only unblank the console if we are called in enabled
265		 * context or a bust_spinlocks cleared the way for us.
266		 */
267		console_unblank();
268	_machine_power_off();
269}
270
271/*
272 * Dummy power off function.
273 */
274void (*pm_power_off)(void) = machine_power_off;
275
276static int __init early_parse_mem(char *p)
277{
278	memory_end = memparse(p, &p);
279	memory_end_set = 1;
280	return 0;
281}
282early_param("mem", early_parse_mem);
283
284unsigned int user_mode = HOME_SPACE_MODE;
285EXPORT_SYMBOL_GPL(user_mode);
286
287static int set_amode_and_uaccess(unsigned long user_amode,
288				 unsigned long user32_amode)
289{
290	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
291			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
292			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
293#ifdef CONFIG_COMPAT
294	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
295			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
296			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
297	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
298			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
299			  PSW32_MASK_PSTATE;
300#endif
301	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
302			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
303
304	if (MACHINE_HAS_MVCOS) {
305		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
306		return 1;
307	} else {
308		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
309		return 0;
310	}
311}
312
313/*
314 * Switch kernel/user addressing modes?
315 */
316static int __init early_parse_switch_amode(char *p)
317{
318	if (user_mode != SECONDARY_SPACE_MODE)
319		user_mode = PRIMARY_SPACE_MODE;
320	return 0;
321}
322early_param("switch_amode", early_parse_switch_amode);
323
324static int __init early_parse_user_mode(char *p)
325{
326	if (p && strcmp(p, "primary") == 0)
327		user_mode = PRIMARY_SPACE_MODE;
328#ifdef CONFIG_S390_EXEC_PROTECT
329	else if (p && strcmp(p, "secondary") == 0)
330		user_mode = SECONDARY_SPACE_MODE;
331#endif
332	else if (!p || strcmp(p, "home") == 0)
333		user_mode = HOME_SPACE_MODE;
334	else
335		return 1;
336	return 0;
337}
338early_param("user_mode", early_parse_user_mode);
339
340#ifdef CONFIG_S390_EXEC_PROTECT
341/*
342 * Enable execute protection?
343 */
344static int __init early_parse_noexec(char *p)
345{
346	if (!strncmp(p, "off", 3))
347		return 0;
348	user_mode = SECONDARY_SPACE_MODE;
349	return 0;
350}
351early_param("noexec", early_parse_noexec);
352#endif /* CONFIG_S390_EXEC_PROTECT */
353
354static void setup_addressing_mode(void)
355{
356	if (user_mode == SECONDARY_SPACE_MODE) {
357		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
358					  PSW32_ASC_SECONDARY))
359			pr_info("Execute protection active, "
360				"mvcos available\n");
361		else
362			pr_info("Execute protection active, "
363				"mvcos not available\n");
364	} else if (user_mode == PRIMARY_SPACE_MODE) {
365		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
366			pr_info("Address spaces switched, "
367				"mvcos available\n");
368		else
369			pr_info("Address spaces switched, "
370				"mvcos not available\n");
371	}
372}
373
374static void __init
375setup_lowcore(void)
376{
377	struct _lowcore *lc;
378
379	/*
380	 * Setup lowcore for boot cpu
381	 */
382	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
383	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
384	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
385	lc->restart_psw.addr =
386		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
387	if (user_mode != HOME_SPACE_MODE)
388		lc->restart_psw.mask |= PSW_ASC_HOME;
389	lc->external_new_psw.mask = psw_kernel_bits;
390	lc->external_new_psw.addr =
391		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
392	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
393	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
394	lc->program_new_psw.mask = psw_kernel_bits;
395	lc->program_new_psw.addr =
396		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
397	lc->mcck_new_psw.mask =
398		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
399	lc->mcck_new_psw.addr =
400		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
401	lc->io_new_psw.mask = psw_kernel_bits;
402	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
403	lc->clock_comparator = -1ULL;
404	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
405	lc->async_stack = (unsigned long)
406		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
407	lc->panic_stack = (unsigned long)
408		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
409	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
410	lc->thread_info = (unsigned long) &init_thread_union;
411	lc->machine_flags = S390_lowcore.machine_flags;
412#ifndef CONFIG_64BIT
413	if (MACHINE_HAS_IEEE) {
414		lc->extended_save_area_addr = (__u32)
415			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
416		/* enable extended save area */
417		__ctl_set_bit(14, 29);
418	}
419#else
420	lc->cmf_hpp = -1ULL;
421	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
422#endif
423	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
424	lc->async_enter_timer = S390_lowcore.async_enter_timer;
425	lc->exit_timer = S390_lowcore.exit_timer;
426	lc->user_timer = S390_lowcore.user_timer;
427	lc->system_timer = S390_lowcore.system_timer;
428	lc->steal_timer = S390_lowcore.steal_timer;
429	lc->last_update_timer = S390_lowcore.last_update_timer;
430	lc->last_update_clock = S390_lowcore.last_update_clock;
431	lc->ftrace_func = S390_lowcore.ftrace_func;
432	set_prefix((u32)(unsigned long) lc);
433	lowcore_ptr[0] = lc;
434}
435
436static void __init
437setup_resources(void)
438{
439	struct resource *res, *sub_res;
440	int i;
441
442	code_resource.start = (unsigned long) &_text;
443	code_resource.end = (unsigned long) &_etext - 1;
444	data_resource.start = (unsigned long) &_etext;
445	data_resource.end = (unsigned long) &_edata - 1;
446
447	for (i = 0; i < MEMORY_CHUNKS; i++) {
448		if (!memory_chunk[i].size)
449			continue;
450		res = alloc_bootmem_low(sizeof(struct resource));
451		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
452		switch (memory_chunk[i].type) {
453		case CHUNK_READ_WRITE:
454			res->name = "System RAM";
455			break;
456		case CHUNK_READ_ONLY:
457			res->name = "System ROM";
458			res->flags |= IORESOURCE_READONLY;
459			break;
460		default:
461			res->name = "reserved";
462		}
463		res->start = memory_chunk[i].addr;
464		res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
465		request_resource(&iomem_resource, res);
466
467		if (code_resource.start >= res->start  &&
468			code_resource.start <= res->end &&
469			code_resource.end > res->end) {
470			sub_res = alloc_bootmem_low(sizeof(struct resource));
471			memcpy(sub_res, &code_resource,
472				sizeof(struct resource));
473			sub_res->end = res->end;
474			code_resource.start = res->end + 1;
475			request_resource(res, sub_res);
476		}
477
478		if (code_resource.start >= res->start &&
479			code_resource.start <= res->end &&
480			code_resource.end <= res->end)
481			request_resource(res, &code_resource);
482
483		if (data_resource.start >= res->start &&
484			data_resource.start <= res->end &&
485			data_resource.end > res->end) {
486			sub_res = alloc_bootmem_low(sizeof(struct resource));
487			memcpy(sub_res, &data_resource,
488				sizeof(struct resource));
489			sub_res->end = res->end;
490			data_resource.start = res->end + 1;
491			request_resource(res, sub_res);
492		}
493
494		if (data_resource.start >= res->start &&
495			data_resource.start <= res->end &&
496			data_resource.end <= res->end)
497			request_resource(res, &data_resource);
498	}
499}
500
501unsigned long real_memory_size;
502EXPORT_SYMBOL_GPL(real_memory_size);
503
504static void __init setup_memory_end(void)
505{
506	unsigned long memory_size;
507	unsigned long max_mem;
508	int i;
509
510#ifdef CONFIG_ZFCPDUMP
511	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
512		memory_end = ZFCPDUMP_HSA_SIZE;
513		memory_end_set = 1;
514	}
515#endif
516	memory_size = 0;
517	memory_end &= PAGE_MASK;
518
519	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
520	memory_end = min(max_mem, memory_end);
521
522	/*
523	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
524	 * extra checks that HOLES_IN_ZONE would require.
525	 */
526	for (i = 0; i < MEMORY_CHUNKS; i++) {
527		unsigned long start, end;
528		struct mem_chunk *chunk;
529		unsigned long align;
530
531		chunk = &memory_chunk[i];
532		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
533		start = (chunk->addr + align - 1) & ~(align - 1);
534		end = (chunk->addr + chunk->size) & ~(align - 1);
535		if (start >= end)
536			memset(chunk, 0, sizeof(*chunk));
537		else {
538			chunk->addr = start;
539			chunk->size = end - start;
540		}
541	}
542
543	for (i = 0; i < MEMORY_CHUNKS; i++) {
544		struct mem_chunk *chunk = &memory_chunk[i];
545
546		real_memory_size = max(real_memory_size,
547				       chunk->addr + chunk->size);
548		if (chunk->addr >= max_mem) {
549			memset(chunk, 0, sizeof(*chunk));
550			continue;
551		}
552		if (chunk->addr + chunk->size > max_mem)
553			chunk->size = max_mem - chunk->addr;
554		memory_size = max(memory_size, chunk->addr + chunk->size);
555	}
556	if (!memory_end)
557		memory_end = memory_size;
558}
559
560static void __init
561setup_memory(void)
562{
563        unsigned long bootmap_size;
564	unsigned long start_pfn, end_pfn;
565	int i;
566
567	/*
568	 * partially used pages are not usable - thus
569	 * we are rounding upwards:
570	 */
571	start_pfn = PFN_UP(__pa(&_end));
572	end_pfn = max_pfn = PFN_DOWN(memory_end);
573
574#ifdef CONFIG_BLK_DEV_INITRD
575	/*
576	 * Move the initrd in case the bitmap of the bootmem allocater
577	 * would overwrite it.
578	 */
579
580	if (INITRD_START && INITRD_SIZE) {
581		unsigned long bmap_size;
582		unsigned long start;
583
584		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
585		bmap_size = PFN_PHYS(bmap_size);
586
587		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
588			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
589
590			if (start + INITRD_SIZE > memory_end) {
591				pr_err("initrd extends beyond end of "
592				       "memory (0x%08lx > 0x%08lx) "
593				       "disabling initrd\n",
594				       start + INITRD_SIZE, memory_end);
595				INITRD_START = INITRD_SIZE = 0;
596			} else {
597				pr_info("Moving initrd (0x%08lx -> "
598					"0x%08lx, size: %ld)\n",
599					INITRD_START, start, INITRD_SIZE);
600				memmove((void *) start, (void *) INITRD_START,
601					INITRD_SIZE);
602				INITRD_START = start;
603			}
604		}
605	}
606#endif
607
608	/*
609	 * Initialize the boot-time allocator
610	 */
611	bootmap_size = init_bootmem(start_pfn, end_pfn);
612
613	/*
614	 * Register RAM areas with the bootmem allocator.
615	 */
616
617	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
618		unsigned long start_chunk, end_chunk, pfn;
619
620		if (memory_chunk[i].type != CHUNK_READ_WRITE)
621			continue;
622		start_chunk = PFN_DOWN(memory_chunk[i].addr);
623		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
624		end_chunk = min(end_chunk, end_pfn);
625		if (start_chunk >= end_chunk)
626			continue;
627		add_active_range(0, start_chunk, end_chunk);
628		pfn = max(start_chunk, start_pfn);
629		for (; pfn < end_chunk; pfn++)
630			page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
631	}
632
633	psw_set_key(PAGE_DEFAULT_KEY);
634
635	free_bootmem_with_active_regions(0, max_pfn);
636
637	/*
638	 * Reserve memory used for lowcore/command line/kernel image.
639	 */
640	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
641	reserve_bootmem((unsigned long)_stext,
642			PFN_PHYS(start_pfn) - (unsigned long)_stext,
643			BOOTMEM_DEFAULT);
644	/*
645	 * Reserve the bootmem bitmap itself as well. We do this in two
646	 * steps (first step was init_bootmem()) because this catches
647	 * the (very unlikely) case of us accidentally initializing the
648	 * bootmem allocator with an invalid RAM area.
649	 */
650	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
651			BOOTMEM_DEFAULT);
652
653#ifdef CONFIG_BLK_DEV_INITRD
654	if (INITRD_START && INITRD_SIZE) {
655		if (INITRD_START + INITRD_SIZE <= memory_end) {
656			reserve_bootmem(INITRD_START, INITRD_SIZE,
657					BOOTMEM_DEFAULT);
658			initrd_start = INITRD_START;
659			initrd_end = initrd_start + INITRD_SIZE;
660		} else {
661			pr_err("initrd extends beyond end of "
662			       "memory (0x%08lx > 0x%08lx) "
663			       "disabling initrd\n",
664			       initrd_start + INITRD_SIZE, memory_end);
665			initrd_start = initrd_end = 0;
666		}
667	}
668#endif
669}
670
671/*
672 * Setup hardware capabilities.
673 */
674static void __init setup_hwcaps(void)
675{
676	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
677	unsigned long long facility_list_extended;
678	unsigned int facility_list;
679	struct cpuid cpu_id;
680	int i;
681
682	facility_list = stfl();
683	/*
684	 * The store facility list bits numbers as found in the principles
685	 * of operation are numbered with bit 1UL<<31 as number 0 to
686	 * bit 1UL<<0 as number 31.
687	 *   Bit 0: instructions named N3, "backported" to esa-mode
688	 *   Bit 2: z/Architecture mode is active
689	 *   Bit 7: the store-facility-list-extended facility is installed
690	 *   Bit 17: the message-security assist is installed
691	 *   Bit 19: the long-displacement facility is installed
692	 *   Bit 21: the extended-immediate facility is installed
693	 *   Bit 22: extended-translation facility 3 is installed
694	 *   Bit 30: extended-translation facility 3 enhancement facility
695	 * These get translated to:
696	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
697	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
698	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
699	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
700	 */
701	for (i = 0; i < 6; i++)
702		if (facility_list & (1UL << (31 - stfl_bits[i])))
703			elf_hwcap |= 1UL << i;
704
705	if ((facility_list & (1UL << (31 - 22)))
706	    && (facility_list & (1UL << (31 - 30))))
707		elf_hwcap |= HWCAP_S390_ETF3EH;
708
709	if ((elf_hwcap & (1UL << 2)) &&
710	    __stfle(&facility_list_extended, 1) > 0) {
711		if ((facility_list_extended & (1ULL << (63 - 42)))
712		    && (facility_list_extended & (1ULL << (63 - 44))))
713			elf_hwcap |= HWCAP_S390_DFP;
714	}
715
716	/*
717	 * Huge page support HWCAP_S390_HPAGE is bit 7.
718	 */
719	if (MACHINE_HAS_HPAGE)
720		elf_hwcap |= HWCAP_S390_HPAGE;
721
722	/*
723	 * 64-bit register support for 31-bit processes
724	 * HWCAP_S390_HIGH_GPRS is bit 9.
725	 */
726	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
727
728	get_cpu_id(&cpu_id);
729	switch (cpu_id.machine) {
730	case 0x9672:
731#if !defined(CONFIG_64BIT)
732	default:	/* Use "g5" as default for 31 bit kernels. */
733#endif
734		strcpy(elf_platform, "g5");
735		break;
736	case 0x2064:
737	case 0x2066:
738#if defined(CONFIG_64BIT)
739	default:	/* Use "z900" as default for 64 bit kernels. */
740#endif
741		strcpy(elf_platform, "z900");
742		break;
743	case 0x2084:
744	case 0x2086:
745		strcpy(elf_platform, "z990");
746		break;
747	case 0x2094:
748	case 0x2096:
749		strcpy(elf_platform, "z9-109");
750		break;
751	case 0x2097:
752	case 0x2098:
753		strcpy(elf_platform, "z10");
754		break;
755	}
756}
757
758/*
759 * Setup function called from init/main.c just after the banner
760 * was printed.
761 */
762
763void __init
764setup_arch(char **cmdline_p)
765{
766        /*
767         * print what head.S has found out about the machine
768         */
769#ifndef CONFIG_64BIT
770	if (MACHINE_IS_VM)
771		pr_info("Linux is running as a z/VM "
772			"guest operating system in 31-bit mode\n");
773	else if (MACHINE_IS_LPAR)
774		pr_info("Linux is running natively in 31-bit mode\n");
775	if (MACHINE_HAS_IEEE)
776		pr_info("The hardware system has IEEE compatible "
777			"floating point units\n");
778	else
779		pr_info("The hardware system has no IEEE compatible "
780			"floating point units\n");
781#else /* CONFIG_64BIT */
782	if (MACHINE_IS_VM)
783		pr_info("Linux is running as a z/VM "
784			"guest operating system in 64-bit mode\n");
785	else if (MACHINE_IS_KVM)
786		pr_info("Linux is running under KVM in 64-bit mode\n");
787	else if (MACHINE_IS_LPAR)
788		pr_info("Linux is running natively in 64-bit mode\n");
789#endif /* CONFIG_64BIT */
790
791	/* Have one command line that is parsed and saved in /proc/cmdline */
792	/* boot_command_line has been already set up in early.c */
793	*cmdline_p = boot_command_line;
794
795        ROOT_DEV = Root_RAM0;
796
797	init_mm.start_code = PAGE_OFFSET;
798	init_mm.end_code = (unsigned long) &_etext;
799	init_mm.end_data = (unsigned long) &_edata;
800	init_mm.brk = (unsigned long) &_end;
801
802	if (MACHINE_HAS_MVCOS)
803		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
804	else
805		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
806
807	parse_early_param();
808
809	setup_ipl();
810	setup_memory_end();
811	setup_addressing_mode();
812	setup_memory();
813	setup_resources();
814	setup_lowcore();
815
816        cpu_init();
817	s390_init_cpu_topology();
818
819	/*
820	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
821	 */
822	setup_hwcaps();
823
824	/*
825	 * Create kernel page tables and switch to virtual addressing.
826	 */
827        paging_init();
828
829        /* Setup default console */
830	conmode_default();
831	set_preferred_console();
832
833	/* Setup zfcpdump support */
834	setup_zfcpdump(console_devno);
835}
836