aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/kernel/setup.c
blob: 6f6350826c81c1f7a1d81071ac0b4ed2df360e17 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
/*
 *  arch/s390/kernel/setup.c
 *
 *  S390 version
 *    Copyright (C) IBM Corp. 1999,2010
 *    Author(s): Hartmut Penner (hp@de.ibm.com),
 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Derived from "arch/i386/kernel/setup.c"
 *    Copyright (C) 1995, Linus Torvalds
 */

/*
 * This file handles the architecture-dependent parts of initialization
 */

#define KMSG_COMPONENT "setup"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/bootmem.h>
#include <linux/root_dev.h>
#include <linux/console.h>
#include <linux/kernel_stat.h>
#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/pfn.h>
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <linux/topology.h>
#include <linux/ftrace.h>

#include <asm/ipl.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/smp.h>
#include <asm/mmu_context.h>
#include <asm/cpcmd.h>
#include <asm/lowcore.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/sections.h>
#include <asm/ebcdic.h>
#include <asm/compat.h>
#include <asm/kvm_virtio.h>

long psw_kernel_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
			   PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
long psw_user_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
			   PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
			   PSW_MASK_PSTATE | PSW_DEFAULT_KEY);

/*
 * User copy operations.
 */
struct uaccess_ops uaccess;
EXPORT_SYMBOL(uaccess);

/*
 * Machine setup..
 */
unsigned int console_mode = 0;
EXPORT_SYMBOL(console_mode);

unsigned int console_devno = -1;
EXPORT_SYMBOL(console_devno);

unsigned int console_irq = -1;
EXPORT_SYMBOL(console_irq);

unsigned long elf_hwcap = 0;
char elf_platform[ELF_PLATFORM_SIZE];

struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];

int __initdata memory_end_set;
unsigned long __initdata memory_end;

/* An array with a pointer to the lowcore of every CPU. */
struct _lowcore *lowcore_ptr[NR_CPUS];
EXPORT_SYMBOL(lowcore_ptr);

/*
 * This is set up by the setup-routine at boot-time
 * for S390 need to find out, what we have to setup
 * using address 0x10400 ...
 */

#include <asm/setup.h>

static struct resource code_resource = {
	.name  = "Kernel code",
	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};

static struct resource data_resource = {
	.name = "Kernel data",
	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};

/*
 * condev= and conmode= setup parameter.
 */

static int __init condev_setup(char *str)
{
	int vdev;

	vdev = simple_strtoul(str, &str, 0);
	if (vdev >= 0 && vdev < 65536) {
		console_devno = vdev;
		console_irq = -1;
	}
	return 1;
}

__setup("condev=", condev_setup);

static void __init set_preferred_console(void)
{
	if (MACHINE_IS_KVM)
		add_preferred_console("hvc", 0, NULL);
	else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
		add_preferred_console("ttyS", 0, NULL);
	else if (CONSOLE_IS_3270)
		add_preferred_console("tty3270", 0, NULL);
}

static int __init conmode_setup(char *str)
{
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
                SET_CONSOLE_SCLP;
#endif
#if defined(CONFIG_TN3215_CONSOLE)
	if (strncmp(str, "3215", 5) == 0)
		SET_CONSOLE_3215;
#endif
#if defined(CONFIG_TN3270_CONSOLE)
	if (strncmp(str, "3270", 5) == 0)
		SET_CONSOLE_3270;
#endif
	set_preferred_console();
        return 1;
}

__setup("conmode=", conmode_setup);

static void __init conmode_default(void)
{
	char query_buffer[1024];
	char *ptr;

        if (MACHINE_IS_VM) {
		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
		ptr = strstr(query_buffer, "SUBCHANNEL =");
		console_irq = simple_strtoul(ptr + 13, NULL, 16);
		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
		ptr = strstr(query_buffer, "CONMODE");
		/*
		 * Set the conmode to 3215 so that the device recognition 
		 * will set the cu_type of the console to 3215. If the
		 * conmode is 3270 and we don't set it back then both
		 * 3215 and the 3270 driver will try to access the console
		 * device (3215 as console and 3270 as normal tty).
		 */
		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
		if (ptr == NULL) {
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
			SET_CONSOLE_SCLP;
#endif
			return;
		}
		if (strncmp(ptr + 8, "3270", 4) == 0) {
#if defined(CONFIG_TN3270_CONSOLE)
			SET_CONSOLE_3270;
#elif defined(CONFIG_TN3215_CONSOLE)
			SET_CONSOLE_3215;
#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
			SET_CONSOLE_SCLP;
#endif
		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
#if defined(CONFIG_TN3215_CONSOLE)
			SET_CONSOLE_3215;
#elif defined(CONFIG_TN3270_CONSOLE)
			SET_CONSOLE_3270;
#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
			SET_CONSOLE_SCLP;
#endif
		}
	} else {
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
		SET_CONSOLE_SCLP;
#endif
	}
}

#ifdef CONFIG_ZFCPDUMP
static void __init setup_zfcpdump(unsigned int console_devno)
{
	static char str[41];

	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
		return;
	if (console_devno != -1)
		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
			ipl_info.data.fcp.dev_id.devno, console_devno);
	else
		sprintf(str, " cio_ignore=all,!0.0.%04x",
			ipl_info.data.fcp.dev_id.devno);
	strcat(boot_command_line, str);
	console_loglevel = 2;
}
#else
static inline void setup_zfcpdump(unsigned int console_devno) {}
#endif /* CONFIG_ZFCPDUMP */

 /*
 * Reboot, halt and power_off stubs. They just call _machine_restart,
 * _machine_halt or _machine_power_off. 
 */

void machine_restart(char *command)
{
	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
		/*
		 * Only unblank the console if we are called in enabled
		 * context or a bust_spinlocks cleared the way for us.
		 */
		console_unblank();
	_machine_restart(command);
}

void machine_halt(void)
{
	if (!in_interrupt() || oops_in_progress)
		/*
		 * Only unblank the console if we are called in enabled
		 * context or a bust_spinlocks cleared the way for us.
		 */
		console_unblank();
	_machine_halt();
}

void machine_power_off(void)
{
	if (!in_interrupt() || oops_in_progress)
		/*
		 * Only unblank the console if we are called in enabled
		 * context or a bust_spinlocks cleared the way for us.
		 */
		console_unblank();
	_machine_power_off();
}

/*
 * Dummy power off function.
 */
void (*pm_power_off)(void) = machine_power_off;

static int __init early_parse_mem(char *p)
{
	memory_end = memparse(p, &p);
	memory_end_set = 1;
	return 0;
}
early_param("mem", early_parse_mem);

unsigned int user_mode = HOME_SPACE_MODE;
EXPORT_SYMBOL_GPL(user_mode);

static int set_amode_and_uaccess(unsigned long user_amode,
				 unsigned long user32_amode)
{
	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
#ifdef CONFIG_COMPAT
	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
			  PSW32_MASK_PSTATE;
#endif
	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;

	if (MACHINE_HAS_MVCOS) {
		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
		return 1;
	} else {
		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
		return 0;
	}
}

/*
 * Switch kernel/user addressing modes?
 */
static int __init early_parse_switch_amode(char *p)
{
	if (user_mode != SECONDARY_SPACE_MODE)
		user_mode = PRIMARY_SPACE_MODE;
	return 0;
}
early_param("switch_amode", early_parse_switch_amode);

static int __init early_parse_user_mode(char *p)
{
	if (p && strcmp(p, "primary") == 0)
		user_mode = PRIMARY_SPACE_MODE;
#ifdef CONFIG_S390_EXEC_PROTECT
	else if (p && strcmp(p, "secondary") == 0)
		user_mode = SECONDARY_SPACE_MODE;
#endif
	else if (!p || strcmp(p, "home") == 0)
		user_mode = HOME_SPACE_MODE;
	else
		return 1;
	return 0;
}
early_param("user_mode", early_parse_user_mode);

#ifdef CONFIG_S390_EXEC_PROTECT
/*
 * Enable execute protection?
 */
static int __init early_parse_noexec(char *p)
{
	if (!strncmp(p, "off", 3))
		return 0;
	user_mode = SECONDARY_SPACE_MODE;
	return 0;
}
early_param("noexec", early_parse_noexec);
#endif /* CONFIG_S390_EXEC_PROTECT */

static void setup_addressing_mode(void)
{
	if (user_mode == SECONDARY_SPACE_MODE) {
		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
					  PSW32_ASC_SECONDARY))
			pr_info("Execute protection active, "
				"mvcos available\n");
		else
			pr_info("Execute protection active, "
				"mvcos not available\n");
	} else if (user_mode == PRIMARY_SPACE_MODE) {
		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
			pr_info("Address spaces switched, "
				"mvcos available\n");
		else
			pr_info("Address spaces switched, "
				"mvcos not available\n");
	}
}

static void __init
setup_lowcore(void)
{
	struct _lowcore *lc;

	/*
	 * Setup lowcore for boot cpu
	 */
	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
	lc->restart_psw.addr =
		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
	if (user_mode != HOME_SPACE_MODE)
		lc->restart_psw.mask |= PSW_ASC_HOME;
	lc->external_new_psw.mask = psw_kernel_bits;
	lc->external_new_psw.addr =
		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
	lc->program_new_psw.mask = psw_kernel_bits;
	lc->program_new_psw.addr =
		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
	lc->mcck_new_psw.mask =
		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
	lc->mcck_new_psw.addr =
		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
	lc->io_new_psw.mask = psw_kernel_bits;
	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
	lc->clock_comparator = -1ULL;
	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
	lc->async_stack = (unsigned long)
		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
	lc->panic_stack = (unsigned long)
		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
	lc->thread_info = (unsigned long) &init_thread_union;
	lc->machine_flags = S390_lowcore.machine_flags;
	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
	       MAX_FACILITY_BIT/8);
#ifndef CONFIG_64BIT
	if (MACHINE_HAS_IEEE) {
		lc->extended_save_area_addr = (__u32)
			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
		/* enable extended save area */
		__ctl_set_bit(14, 29);
	}
#else
	lc->cmf_hpp = -1ULL;
	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
#endif
	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
	lc->async_enter_timer = S390_lowcore.async_enter_timer;
	lc->exit_timer = S390_lowcore.exit_timer;
	lc->user_timer = S390_lowcore.user_timer;
	lc->system_timer = S390_lowcore.system_timer;
	lc->steal_timer = S390_lowcore.steal_timer;
	lc->last_update_timer = S390_lowcore.last_update_timer;
	lc->last_update_clock = S390_lowcore.last_update_clock;
	lc->ftrace_func = S390_lowcore.ftrace_func;
	set_prefix((u32)(unsigned long) lc);
	lowcore_ptr[0] = lc;
}

static void __init
setup_resources(void)
{
	struct resource *res, *sub_res;
	int i;

	code_resource.start = (unsigned long) &_text;
	code_resource.end = (unsigned long) &_etext - 1;
	data_resource.start = (unsigned long) &_etext;
	data_resource.end = (unsigned long) &_edata - 1;

	for (i = 0; i < MEMORY_CHUNKS; i++) {
		if (!memory_chunk[i].size)
			continue;
		res = alloc_bootmem_low(sizeof(struct resource));
		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
		switch (memory_chunk[i].type) {
		case CHUNK_READ_WRITE:
			res->name = "System RAM";
			break;
		case CHUNK_READ_ONLY:
			res->name = "System ROM";
			res->flags |= IORESOURCE_READONLY;
			break;
		default:
			res->name = "reserved";
		}
		res->start = memory_chunk[i].addr;
		res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
		request_resource(&iomem_resource, res);

		if (code_resource.start >= res->start  &&
			code_resource.start <= res->end &&
			code_resource.end > res->end) {
			sub_res = alloc_bootmem_low(sizeof(struct resource));
			memcpy(sub_res, &code_resource,
				sizeof(struct resource));
			sub_res->end = res->end;
			code_resource.start = res->end + 1;
			request_resource(res, sub_res);
		}

		if (code_resource.start >= res->start &&
			code_resource.start <= res->end &&
			code_resource.end <= res->end)
			request_resource(res, &code_resource);

		if (data_resource.start >= res->start &&
			data_resource.start <= res->end &&
			data_resource.end > res->end) {
			sub_res = alloc_bootmem_low(sizeof(struct resource));
			memcpy(sub_res, &data_resource,
				sizeof(struct resource));
			sub_res->end = res->end;
			data_resource.start = res->end + 1;
			request_resource(res, sub_res);
		}

		if (data_resource.start >= res->start &&
			data_resource.start <= res->end &&
			data_resource.end <= res->end)
			request_resource(res, &data_resource);
	}
}

unsigned long real_memory_size;
EXPORT_SYMBOL_GPL(real_memory_size);

static void __init setup_memory_end(void)
{
	unsigned long memory_size;
	unsigned long max_mem;
	int i;

#ifdef CONFIG_ZFCPDUMP
	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
		memory_end = ZFCPDUMP_HSA_SIZE;
		memory_end_set = 1;
	}
#endif
	memory_size = 0;
	memory_end &= PAGE_MASK;

	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
	memory_end = min(max_mem, memory_end);

	/*
	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
	 * extra checks that HOLES_IN_ZONE would require.
	 */
	for (i = 0; i < MEMORY_CHUNKS; i++) {
		unsigned long start, end;
		struct mem_chunk *chunk;
		unsigned long align;

		chunk = &memory_chunk[i];
		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
		start = (chunk->addr + align - 1) & ~(align - 1);
		end = (chunk->addr + chunk->size) & ~(align - 1);
		if (start >= end)
			memset(chunk, 0, sizeof(*chunk));
		else {
			chunk->addr = start;
			chunk->size = end - start;
		}
	}

	for (i = 0; i < MEMORY_CHUNKS; i++) {
		struct mem_chunk *chunk = &memory_chunk[i];

		real_memory_size = max(real_memory_size,
				       chunk->addr + chunk->size);
		if (chunk->addr >= max_mem) {
			memset(chunk, 0, sizeof(*chunk));
			continue;
		}
		if (chunk->addr + chunk->size > max_mem)
			chunk->size = max_mem - chunk->addr;
		memory_size = max(memory_size, chunk->addr + chunk->size);
	}
	if (!memory_end)
		memory_end = memory_size;
}

static void __init
setup_memory(void)
{
        unsigned long bootmap_size;
	unsigned long start_pfn, end_pfn;
	int i;

	/*
	 * partially used pages are not usable - thus
	 * we are rounding upwards:
	 */
	start_pfn = PFN_UP(__pa(&_end));
	end_pfn = max_pfn = PFN_DOWN(memory_end);

#ifdef CONFIG_BLK_DEV_INITRD
	/*
	 * Move the initrd in case the bitmap of the bootmem allocater
	 * would overwrite it.
	 */

	if (INITRD_START && INITRD_SIZE) {
		unsigned long bmap_size;
		unsigned long start;

		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
		bmap_size = PFN_PHYS(bmap_size);

		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;

			if (start + INITRD_SIZE > memory_end) {
				pr_err("initrd extends beyond end of "
				       "memory (0x%08lx > 0x%08lx) "
				       "disabling initrd\n",
				       start + INITRD_SIZE, memory_end);
				INITRD_START = INITRD_SIZE = 0;
			} else {
				pr_info("Moving initrd (0x%08lx -> "
					"0x%08lx, size: %ld)\n",
					INITRD_START, start, INITRD_SIZE);
				memmove((void *) start, (void *) INITRD_START,
					INITRD_SIZE);
				INITRD_START = start;
			}
		}
	}
#endif

	/*
	 * Initialize the boot-time allocator
	 */
	bootmap_size = init_bootmem(start_pfn, end_pfn);

	/*
	 * Register RAM areas with the bootmem allocator.
	 */

	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
		unsigned long start_chunk, end_chunk, pfn;

		if (memory_chunk[i].type != CHUNK_READ_WRITE)
			continue;
		start_chunk = PFN_DOWN(memory_chunk[i].addr);
		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
		end_chunk = min(end_chunk, end_pfn);
		if (start_chunk >= end_chunk)
			continue;
		add_active_range(0, start_chunk, end_chunk);
		pfn = max(start_chunk, start_pfn);
		for (; pfn < end_chunk; pfn++)
			page_set_storage_key(PFN_PHYS(pfn),
					     PAGE_DEFAULT_KEY, 0);
	}

	psw_set_key(PAGE_DEFAULT_KEY);

	free_bootmem_with_active_regions(0, max_pfn);

	/*
	 * Reserve memory used for lowcore/command line/kernel image.
	 */
	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
	reserve_bootmem((unsigned long)_stext,
			PFN_PHYS(start_pfn) - (unsigned long)_stext,
			BOOTMEM_DEFAULT);
	/*
	 * Reserve the bootmem bitmap itself as well. We do this in two
	 * steps (first step was init_bootmem()) because this catches
	 * the (very unlikely) case of us accidentally initializing the
	 * bootmem allocator with an invalid RAM area.
	 */
	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
			BOOTMEM_DEFAULT);

#ifdef CONFIG_BLK_DEV_INITRD
	if (INITRD_START && INITRD_SIZE) {
		if (INITRD_START + INITRD_SIZE <= memory_end) {
			reserve_bootmem(INITRD_START, INITRD_SIZE,
					BOOTMEM_DEFAULT);
			initrd_start = INITRD_START;
			initrd_end = initrd_start + INITRD_SIZE;
		} else {
			pr_err("initrd extends beyond end of "
			       "memory (0x%08lx > 0x%08lx) "
			       "disabling initrd\n",
			       initrd_start + INITRD_SIZE, memory_end);
			initrd_start = initrd_end = 0;
		}
	}
#endif
}

/*
 * Setup hardware capabilities.
 */
static void __init setup_hwcaps(void)
{
	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
	struct cpuid cpu_id;
	int i;

	/*
	 * The store facility list bits numbers as found in the principles
	 * of operation are numbered with bit 1UL<<31 as number 0 to
	 * bit 1UL<<0 as number 31.
	 *   Bit 0: instructions named N3, "backported" to esa-mode
	 *   Bit 2: z/Architecture mode is active
	 *   Bit 7: the store-facility-list-extended facility is installed
	 *   Bit 17: the message-security assist is installed
	 *   Bit 19: the long-displacement facility is installed
	 *   Bit 21: the extended-immediate facility is installed
	 *   Bit 22: extended-translation facility 3 is installed
	 *   Bit 30: extended-translation facility 3 enhancement facility
	 * These get translated to:
	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
	 */
	for (i = 0; i < 6; i++)
		if (test_facility(stfl_bits[i]))
			elf_hwcap |= 1UL << i;

	if (test_facility(22) && test_facility(30))
		elf_hwcap |= HWCAP_S390_ETF3EH;

	/*
	 * Check for additional facilities with store-facility-list-extended.
	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
	 * as stored by stfl, bits 32-xxx contain additional facilities.
	 * How many facility words are stored depends on the number of
	 * doublewords passed to the instruction. The additional facilites
	 * are:
	 *   Bit 42: decimal floating point facility is installed
	 *   Bit 44: perform floating point operation facility is installed
	 * translated to:
	 *   HWCAP_S390_DFP bit 6 (42 && 44).
	 */
	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
		elf_hwcap |= HWCAP_S390_DFP;

	/*
	 * Huge page support HWCAP_S390_HPAGE is bit 7.
	 */
	if (MACHINE_HAS_HPAGE)
		elf_hwcap |= HWCAP_S390_HPAGE;

	/*
	 * 64-bit register support for 31-bit processes
	 * HWCAP_S390_HIGH_GPRS is bit 9.
	 */
	elf_hwcap |= HWCAP_S390_HIGH_GPRS;

	get_cpu_id(&cpu_id);
	switch (cpu_id.machine) {
	case 0x9672:
#if !defined(CONFIG_64BIT)
	default:	/* Use "g5" as default for 31 bit kernels. */
#endif
		strcpy(elf_platform, "g5");
		break;
	case 0x2064:
	case 0x2066:
#if defined(CONFIG_64BIT)
	default:	/* Use "z900" as default for 64 bit kernels. */
#endif
		strcpy(elf_platform, "z900");
		break;
	case 0x2084:
	case 0x2086:
		strcpy(elf_platform, "z990");
		break;
	case 0x2094:
	case 0x2096:
		strcpy(elf_platform, "z9-109");
		break;
	case 0x2097:
	case 0x2098:
		strcpy(elf_platform, "z10");
		break;
	case 0x2817:
		strcpy(elf_platform, "z196");
		break;
	}
}

/*
 * Setup function called from init/main.c just after the banner
 * was printed.
 */

void __init
setup_arch(char **cmdline_p)
{
        /*
         * print what head.S has found out about the machine
         */
#ifndef CONFIG_64BIT
	if (MACHINE_IS_VM)
		pr_info("Linux is running as a z/VM "
			"guest operating system in 31-bit mode\n");
	else if (MACHINE_IS_LPAR)
		pr_info("Linux is running natively in 31-bit mode\n");
	if (MACHINE_HAS_IEEE)
		pr_info("The hardware system has IEEE compatible "
			"floating point units\n");
	else
		pr_info("The hardware system has no IEEE compatible "
			"floating point units\n");
#else /* CONFIG_64BIT */
	if (MACHINE_IS_VM)
		pr_info("Linux is running as a z/VM "
			"guest operating system in 64-bit mode\n");
	else if (MACHINE_IS_KVM)
		pr_info("Linux is running under KVM in 64-bit mode\n");
	else if (MACHINE_IS_LPAR)
		pr_info("Linux is running natively in 64-bit mode\n");
#endif /* CONFIG_64BIT */

	/* Have one command line that is parsed and saved in /proc/cmdline */
	/* boot_command_line has been already set up in early.c */
	*cmdline_p = boot_command_line;

        ROOT_DEV = Root_RAM0;

	init_mm.start_code = PAGE_OFFSET;
	init_mm.end_code = (unsigned long) &_etext;
	init_mm.end_data = (unsigned long) &_edata;
	init_mm.brk = (unsigned long) &_end;

	if (MACHINE_HAS_MVCOS)
		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
	else
		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));

	parse_early_param();

	setup_ipl();
	setup_memory_end();
	setup_addressing_mode();
	setup_memory();
	setup_resources();
	setup_lowcore();

        cpu_init();
	s390_init_cpu_topology();

	/*
	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
	 */
	setup_hwcaps();

	/*
	 * Create kernel page tables and switch to virtual addressing.
	 */
        paging_init();

        /* Setup default console */
	conmode_default();
	set_preferred_console();

	/* Setup zfcpdump support */
	setup_zfcpdump(console_devno);
}