xref: /openbmc/linux/arch/s390/kernel/setup.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  *  arch/s390/kernel/setup.c
3  *
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)
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/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 
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 
61 long psw_kernel_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
62 			   PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
63 long psw_user_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
64 			   PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
65 			   PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
66 
67 /*
68  * User copy operations.
69  */
70 struct uaccess_ops uaccess;
71 EXPORT_SYMBOL(uaccess);
72 
73 /*
74  * Machine setup..
75  */
76 unsigned int console_mode = 0;
77 EXPORT_SYMBOL(console_mode);
78 
79 unsigned int console_devno = -1;
80 EXPORT_SYMBOL(console_devno);
81 
82 unsigned int console_irq = -1;
83 EXPORT_SYMBOL(console_irq);
84 
85 unsigned long machine_flags;
86 EXPORT_SYMBOL(machine_flags);
87 
88 unsigned long elf_hwcap = 0;
89 char elf_platform[ELF_PLATFORM_SIZE];
90 
91 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
92 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
93 
94 int __initdata memory_end_set;
95 unsigned long __initdata memory_end;
96 
97 /* An array with a pointer to the lowcore of every CPU. */
98 struct _lowcore *lowcore_ptr[NR_CPUS];
99 EXPORT_SYMBOL(lowcore_ptr);
100 
101 /*
102  * This is set up by the setup-routine at boot-time
103  * for S390 need to find out, what we have to setup
104  * using address 0x10400 ...
105  */
106 
107 #include <asm/setup.h>
108 
109 static struct resource code_resource = {
110 	.name  = "Kernel code",
111 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
112 };
113 
114 static struct resource data_resource = {
115 	.name = "Kernel data",
116 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
117 };
118 
119 /*
120  * cpu_init() initializes state that is per-CPU.
121  */
122 void __cpuinit cpu_init(void)
123 {
124         /*
125          * Store processor id in lowcore (used e.g. in timer_interrupt)
126          */
127 	get_cpu_id(&S390_lowcore.cpu_id);
128 
129         /*
130          * Force FPU initialization:
131          */
132         clear_thread_flag(TIF_USEDFPU);
133         clear_used_math();
134 
135 	atomic_inc(&init_mm.mm_count);
136 	current->active_mm = &init_mm;
137 	BUG_ON(current->mm);
138         enter_lazy_tlb(&init_mm, current);
139 }
140 
141 /*
142  * condev= and conmode= setup parameter.
143  */
144 
145 static int __init condev_setup(char *str)
146 {
147 	int vdev;
148 
149 	vdev = simple_strtoul(str, &str, 0);
150 	if (vdev >= 0 && vdev < 65536) {
151 		console_devno = vdev;
152 		console_irq = -1;
153 	}
154 	return 1;
155 }
156 
157 __setup("condev=", condev_setup);
158 
159 static int __init conmode_setup(char *str)
160 {
161 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
162 	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
163                 SET_CONSOLE_SCLP;
164 #endif
165 #if defined(CONFIG_TN3215_CONSOLE)
166 	if (strncmp(str, "3215", 5) == 0)
167 		SET_CONSOLE_3215;
168 #endif
169 #if defined(CONFIG_TN3270_CONSOLE)
170 	if (strncmp(str, "3270", 5) == 0)
171 		SET_CONSOLE_3270;
172 #endif
173         return 1;
174 }
175 
176 __setup("conmode=", conmode_setup);
177 
178 static void __init conmode_default(void)
179 {
180 	char query_buffer[1024];
181 	char *ptr;
182 
183         if (MACHINE_IS_VM) {
184 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
185 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
186 		ptr = strstr(query_buffer, "SUBCHANNEL =");
187 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
188 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
189 		ptr = strstr(query_buffer, "CONMODE");
190 		/*
191 		 * Set the conmode to 3215 so that the device recognition
192 		 * will set the cu_type of the console to 3215. If the
193 		 * conmode is 3270 and we don't set it back then both
194 		 * 3215 and the 3270 driver will try to access the console
195 		 * device (3215 as console and 3270 as normal tty).
196 		 */
197 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
198 		if (ptr == NULL) {
199 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
200 			SET_CONSOLE_SCLP;
201 #endif
202 			return;
203 		}
204 		if (strncmp(ptr + 8, "3270", 4) == 0) {
205 #if defined(CONFIG_TN3270_CONSOLE)
206 			SET_CONSOLE_3270;
207 #elif defined(CONFIG_TN3215_CONSOLE)
208 			SET_CONSOLE_3215;
209 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
210 			SET_CONSOLE_SCLP;
211 #endif
212 		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
213 #if defined(CONFIG_TN3215_CONSOLE)
214 			SET_CONSOLE_3215;
215 #elif defined(CONFIG_TN3270_CONSOLE)
216 			SET_CONSOLE_3270;
217 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
218 			SET_CONSOLE_SCLP;
219 #endif
220 		}
221 	} else {
222 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
223 		SET_CONSOLE_SCLP;
224 #endif
225 	}
226 }
227 
228 #ifdef CONFIG_ZFCPDUMP
229 static void __init setup_zfcpdump(unsigned int console_devno)
230 {
231 	static char str[41];
232 
233 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
234 		return;
235 	if (console_devno != -1)
236 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
237 			ipl_info.data.fcp.dev_id.devno, console_devno);
238 	else
239 		sprintf(str, " cio_ignore=all,!0.0.%04x",
240 			ipl_info.data.fcp.dev_id.devno);
241 	strcat(boot_command_line, str);
242 	console_loglevel = 2;
243 }
244 #else
245 static inline void setup_zfcpdump(unsigned int console_devno) {}
246 #endif /* CONFIG_ZFCPDUMP */
247 
248  /*
249  * Reboot, halt and power_off stubs. They just call _machine_restart,
250  * _machine_halt or _machine_power_off.
251  */
252 
253 void machine_restart(char *command)
254 {
255 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
256 		/*
257 		 * Only unblank the console if we are called in enabled
258 		 * context or a bust_spinlocks cleared the way for us.
259 		 */
260 		console_unblank();
261 	_machine_restart(command);
262 }
263 
264 void machine_halt(void)
265 {
266 	if (!in_interrupt() || oops_in_progress)
267 		/*
268 		 * Only unblank the console if we are called in enabled
269 		 * context or a bust_spinlocks cleared the way for us.
270 		 */
271 		console_unblank();
272 	_machine_halt();
273 }
274 
275 void machine_power_off(void)
276 {
277 	if (!in_interrupt() || oops_in_progress)
278 		/*
279 		 * Only unblank the console if we are called in enabled
280 		 * context or a bust_spinlocks cleared the way for us.
281 		 */
282 		console_unblank();
283 	_machine_power_off();
284 }
285 
286 /*
287  * Dummy power off function.
288  */
289 void (*pm_power_off)(void) = machine_power_off;
290 
291 static int __init early_parse_mem(char *p)
292 {
293 	memory_end = memparse(p, &p);
294 	memory_end_set = 1;
295 	return 0;
296 }
297 early_param("mem", early_parse_mem);
298 
299 #ifdef CONFIG_S390_SWITCH_AMODE
300 unsigned int switch_amode = 0;
301 EXPORT_SYMBOL_GPL(switch_amode);
302 
303 static int set_amode_and_uaccess(unsigned long user_amode,
304 				 unsigned long user32_amode)
305 {
306 	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
307 			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
308 			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
309 #ifdef CONFIG_COMPAT
310 	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
311 			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
312 			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
313 	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
314 			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
315 			  PSW32_MASK_PSTATE;
316 #endif
317 	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
318 			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
319 
320 	if (MACHINE_HAS_MVCOS) {
321 		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
322 		return 1;
323 	} else {
324 		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
325 		return 0;
326 	}
327 }
328 
329 /*
330  * Switch kernel/user addressing modes?
331  */
332 static int __init early_parse_switch_amode(char *p)
333 {
334 	switch_amode = 1;
335 	return 0;
336 }
337 early_param("switch_amode", early_parse_switch_amode);
338 
339 #else /* CONFIG_S390_SWITCH_AMODE */
340 static inline int set_amode_and_uaccess(unsigned long user_amode,
341 					unsigned long user32_amode)
342 {
343 	return 0;
344 }
345 #endif /* CONFIG_S390_SWITCH_AMODE */
346 
347 #ifdef CONFIG_S390_EXEC_PROTECT
348 unsigned int s390_noexec = 0;
349 EXPORT_SYMBOL_GPL(s390_noexec);
350 
351 /*
352  * Enable execute protection?
353  */
354 static int __init early_parse_noexec(char *p)
355 {
356 	if (!strncmp(p, "off", 3))
357 		return 0;
358 	switch_amode = 1;
359 	s390_noexec = 1;
360 	return 0;
361 }
362 early_param("noexec", early_parse_noexec);
363 #endif /* CONFIG_S390_EXEC_PROTECT */
364 
365 static void setup_addressing_mode(void)
366 {
367 	if (s390_noexec) {
368 		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
369 					  PSW32_ASC_SECONDARY))
370 			pr_info("Execute protection active, "
371 				"mvcos available\n");
372 		else
373 			pr_info("Execute protection active, "
374 				"mvcos not available\n");
375 	} else if (switch_amode) {
376 		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
377 			pr_info("Address spaces switched, "
378 				"mvcos available\n");
379 		else
380 			pr_info("Address spaces switched, "
381 				"mvcos not available\n");
382 	}
383 #ifdef CONFIG_TRACE_IRQFLAGS
384 	sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
385 	io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
386 #endif
387 }
388 
389 static void __init
390 setup_lowcore(void)
391 {
392 	struct _lowcore *lc;
393 	int lc_pages;
394 
395 	/*
396 	 * Setup lowcore for boot cpu
397 	 */
398 	lc_pages = sizeof(void *) == 8 ? 2 : 1;
399 	lc = (struct _lowcore *)
400 		__alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
401 	memset(lc, 0, lc_pages * PAGE_SIZE);
402 	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
403 	lc->restart_psw.addr =
404 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
405 	if (switch_amode)
406 		lc->restart_psw.mask |= PSW_ASC_HOME;
407 	lc->external_new_psw.mask = psw_kernel_bits;
408 	lc->external_new_psw.addr =
409 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
410 	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
411 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
412 	lc->program_new_psw.mask = psw_kernel_bits;
413 	lc->program_new_psw.addr =
414 		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
415 	lc->mcck_new_psw.mask =
416 		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
417 	lc->mcck_new_psw.addr =
418 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
419 	lc->io_new_psw.mask = psw_kernel_bits;
420 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
421 	lc->clock_comparator = -1ULL;
422 	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
423 	lc->async_stack = (unsigned long)
424 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
425 	lc->panic_stack = (unsigned long)
426 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
427 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
428 	lc->thread_info = (unsigned long) &init_thread_union;
429 #ifndef CONFIG_64BIT
430 	if (MACHINE_HAS_IEEE) {
431 		lc->extended_save_area_addr = (__u32)
432 			__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
433 		/* enable extended save area */
434 		__ctl_set_bit(14, 29);
435 	}
436 #else
437 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
438 #endif
439 	set_prefix((u32)(unsigned long) lc);
440 	lowcore_ptr[0] = lc;
441 }
442 
443 static void __init
444 setup_resources(void)
445 {
446 	struct resource *res, *sub_res;
447 	int i;
448 
449 	code_resource.start = (unsigned long) &_text;
450 	code_resource.end = (unsigned long) &_etext - 1;
451 	data_resource.start = (unsigned long) &_etext;
452 	data_resource.end = (unsigned long) &_edata - 1;
453 
454 	for (i = 0; i < MEMORY_CHUNKS; i++) {
455 		if (!memory_chunk[i].size)
456 			continue;
457 		res = alloc_bootmem_low(sizeof(struct resource));
458 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
459 		switch (memory_chunk[i].type) {
460 		case CHUNK_READ_WRITE:
461 			res->name = "System RAM";
462 			break;
463 		case CHUNK_READ_ONLY:
464 			res->name = "System ROM";
465 			res->flags |= IORESOURCE_READONLY;
466 			break;
467 		default:
468 			res->name = "reserved";
469 		}
470 		res->start = memory_chunk[i].addr;
471 		res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
472 		request_resource(&iomem_resource, res);
473 
474 		if (code_resource.start >= res->start  &&
475 			code_resource.start <= res->end &&
476 			code_resource.end > res->end) {
477 			sub_res = alloc_bootmem_low(sizeof(struct resource));
478 			memcpy(sub_res, &code_resource,
479 				sizeof(struct resource));
480 			sub_res->end = res->end;
481 			code_resource.start = res->end + 1;
482 			request_resource(res, sub_res);
483 		}
484 
485 		if (code_resource.start >= res->start &&
486 			code_resource.start <= res->end &&
487 			code_resource.end <= res->end)
488 			request_resource(res, &code_resource);
489 
490 		if (data_resource.start >= res->start &&
491 			data_resource.start <= res->end &&
492 			data_resource.end > res->end) {
493 			sub_res = alloc_bootmem_low(sizeof(struct resource));
494 			memcpy(sub_res, &data_resource,
495 				sizeof(struct resource));
496 			sub_res->end = res->end;
497 			data_resource.start = res->end + 1;
498 			request_resource(res, sub_res);
499 		}
500 
501 		if (data_resource.start >= res->start &&
502 			data_resource.start <= res->end &&
503 			data_resource.end <= res->end)
504 			request_resource(res, &data_resource);
505 	}
506 }
507 
508 unsigned long real_memory_size;
509 EXPORT_SYMBOL_GPL(real_memory_size);
510 
511 static void __init setup_memory_end(void)
512 {
513 	unsigned long memory_size;
514 	unsigned long max_mem;
515 	int i;
516 
517 #ifdef CONFIG_ZFCPDUMP
518 	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
519 		memory_end = ZFCPDUMP_HSA_SIZE;
520 		memory_end_set = 1;
521 	}
522 #endif
523 	memory_size = 0;
524 	memory_end &= PAGE_MASK;
525 
526 	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
527 	memory_end = min(max_mem, memory_end);
528 
529 	/*
530 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
531 	 * extra checks that HOLES_IN_ZONE would require.
532 	 */
533 	for (i = 0; i < MEMORY_CHUNKS; i++) {
534 		unsigned long start, end;
535 		struct mem_chunk *chunk;
536 		unsigned long align;
537 
538 		chunk = &memory_chunk[i];
539 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
540 		start = (chunk->addr + align - 1) & ~(align - 1);
541 		end = (chunk->addr + chunk->size) & ~(align - 1);
542 		if (start >= end)
543 			memset(chunk, 0, sizeof(*chunk));
544 		else {
545 			chunk->addr = start;
546 			chunk->size = end - start;
547 		}
548 	}
549 
550 	for (i = 0; i < MEMORY_CHUNKS; i++) {
551 		struct mem_chunk *chunk = &memory_chunk[i];
552 
553 		real_memory_size = max(real_memory_size,
554 				       chunk->addr + chunk->size);
555 		if (chunk->addr >= max_mem) {
556 			memset(chunk, 0, sizeof(*chunk));
557 			continue;
558 		}
559 		if (chunk->addr + chunk->size > max_mem)
560 			chunk->size = max_mem - chunk->addr;
561 		memory_size = max(memory_size, chunk->addr + chunk->size);
562 	}
563 	if (!memory_end)
564 		memory_end = memory_size;
565 }
566 
567 static void __init
568 setup_memory(void)
569 {
570         unsigned long bootmap_size;
571 	unsigned long start_pfn, end_pfn;
572 	int i;
573 
574 	/*
575 	 * partially used pages are not usable - thus
576 	 * we are rounding upwards:
577 	 */
578 	start_pfn = PFN_UP(__pa(&_end));
579 	end_pfn = max_pfn = PFN_DOWN(memory_end);
580 
581 #ifdef CONFIG_BLK_DEV_INITRD
582 	/*
583 	 * Move the initrd in case the bitmap of the bootmem allocater
584 	 * would overwrite it.
585 	 */
586 
587 	if (INITRD_START && INITRD_SIZE) {
588 		unsigned long bmap_size;
589 		unsigned long start;
590 
591 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
592 		bmap_size = PFN_PHYS(bmap_size);
593 
594 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
595 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
596 
597 			if (start + INITRD_SIZE > memory_end) {
598 				pr_err("initrd extends beyond end of "
599 				       "memory (0x%08lx > 0x%08lx) "
600 				       "disabling initrd\n",
601 				       start + INITRD_SIZE, memory_end);
602 				INITRD_START = INITRD_SIZE = 0;
603 			} else {
604 				pr_info("Moving initrd (0x%08lx -> "
605 					"0x%08lx, size: %ld)\n",
606 					INITRD_START, start, INITRD_SIZE);
607 				memmove((void *) start, (void *) INITRD_START,
608 					INITRD_SIZE);
609 				INITRD_START = start;
610 			}
611 		}
612 	}
613 #endif
614 
615 	/*
616 	 * Initialize the boot-time allocator
617 	 */
618 	bootmap_size = init_bootmem(start_pfn, end_pfn);
619 
620 	/*
621 	 * Register RAM areas with the bootmem allocator.
622 	 */
623 
624 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
625 		unsigned long start_chunk, end_chunk, pfn;
626 
627 		if (memory_chunk[i].type != CHUNK_READ_WRITE)
628 			continue;
629 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
630 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
631 		end_chunk = min(end_chunk, end_pfn);
632 		if (start_chunk >= end_chunk)
633 			continue;
634 		add_active_range(0, start_chunk, end_chunk);
635 		pfn = max(start_chunk, start_pfn);
636 		for (; pfn < end_chunk; pfn++)
637 			page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
638 	}
639 
640 	psw_set_key(PAGE_DEFAULT_KEY);
641 
642 	free_bootmem_with_active_regions(0, max_pfn);
643 
644 	/*
645 	 * Reserve memory used for lowcore/command line/kernel image.
646 	 */
647 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
648 	reserve_bootmem((unsigned long)_stext,
649 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
650 			BOOTMEM_DEFAULT);
651 	/*
652 	 * Reserve the bootmem bitmap itself as well. We do this in two
653 	 * steps (first step was init_bootmem()) because this catches
654 	 * the (very unlikely) case of us accidentally initializing the
655 	 * bootmem allocator with an invalid RAM area.
656 	 */
657 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
658 			BOOTMEM_DEFAULT);
659 
660 #ifdef CONFIG_BLK_DEV_INITRD
661 	if (INITRD_START && INITRD_SIZE) {
662 		if (INITRD_START + INITRD_SIZE <= memory_end) {
663 			reserve_bootmem(INITRD_START, INITRD_SIZE,
664 					BOOTMEM_DEFAULT);
665 			initrd_start = INITRD_START;
666 			initrd_end = initrd_start + INITRD_SIZE;
667 		} else {
668 			pr_err("initrd extends beyond end of "
669 			       "memory (0x%08lx > 0x%08lx) "
670 			       "disabling initrd\n",
671 			       initrd_start + INITRD_SIZE, memory_end);
672 			initrd_start = initrd_end = 0;
673 		}
674 	}
675 #endif
676 }
677 
678 /*
679  * Setup hardware capabilities.
680  */
681 static void __init setup_hwcaps(void)
682 {
683 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
684 	unsigned long long facility_list_extended;
685 	unsigned int facility_list;
686 	int i;
687 
688 	facility_list = stfl();
689 	/*
690 	 * The store facility list bits numbers as found in the principles
691 	 * of operation are numbered with bit 1UL<<31 as number 0 to
692 	 * bit 1UL<<0 as number 31.
693 	 *   Bit 0: instructions named N3, "backported" to esa-mode
694 	 *   Bit 2: z/Architecture mode is active
695 	 *   Bit 7: the store-facility-list-extended facility is installed
696 	 *   Bit 17: the message-security assist is installed
697 	 *   Bit 19: the long-displacement facility is installed
698 	 *   Bit 21: the extended-immediate facility is installed
699 	 *   Bit 22: extended-translation facility 3 is installed
700 	 *   Bit 30: extended-translation facility 3 enhancement facility
701 	 * These get translated to:
702 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
703 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
704 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
705 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
706 	 */
707 	for (i = 0; i < 6; i++)
708 		if (facility_list & (1UL << (31 - stfl_bits[i])))
709 			elf_hwcap |= 1UL << i;
710 
711 	if ((facility_list & (1UL << (31 - 22)))
712 	    && (facility_list & (1UL << (31 - 30))))
713 		elf_hwcap |= 1UL << 8;
714 
715 	/*
716 	 * Check for additional facilities with store-facility-list-extended.
717 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
718 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
719 	 * as stored by stfl, bits 32-xxx contain additional facilities.
720 	 * How many facility words are stored depends on the number of
721 	 * doublewords passed to the instruction. The additional facilites
722 	 * are:
723 	 *   Bit 42: decimal floating point facility is installed
724 	 *   Bit 44: perform floating point operation facility is installed
725 	 * translated to:
726 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
727 	 */
728 	if ((elf_hwcap & (1UL << 2)) &&
729 	    __stfle(&facility_list_extended, 1) > 0) {
730 		if ((facility_list_extended & (1ULL << (63 - 42)))
731 		    && (facility_list_extended & (1ULL << (63 - 44))))
732 			elf_hwcap |= 1UL << 6;
733 	}
734 
735 	if (MACHINE_HAS_HPAGE)
736 		elf_hwcap |= 1UL << 7;
737 
738 	switch (S390_lowcore.cpu_id.machine) {
739 	case 0x9672:
740 #if !defined(CONFIG_64BIT)
741 	default:	/* Use "g5" as default for 31 bit kernels. */
742 #endif
743 		strcpy(elf_platform, "g5");
744 		break;
745 	case 0x2064:
746 	case 0x2066:
747 #if defined(CONFIG_64BIT)
748 	default:	/* Use "z900" as default for 64 bit kernels. */
749 #endif
750 		strcpy(elf_platform, "z900");
751 		break;
752 	case 0x2084:
753 	case 0x2086:
754 		strcpy(elf_platform, "z990");
755 		break;
756 	case 0x2094:
757 	case 0x2096:
758 		strcpy(elf_platform, "z9-109");
759 		break;
760 	case 0x2097:
761 	case 0x2098:
762 		strcpy(elf_platform, "z10");
763 		break;
764 	}
765 }
766 
767 /*
768  * Setup function called from init/main.c just after the banner
769  * was printed.
770  */
771 
772 void __init
773 setup_arch(char **cmdline_p)
774 {
775 	/* set up preferred console */
776 	add_preferred_console("ttyS", 0, NULL);
777 
778         /*
779          * print what head.S has found out about the machine
780          */
781 #ifndef CONFIG_64BIT
782 	if (MACHINE_IS_VM)
783 		pr_info("Linux is running as a z/VM "
784 			"guest operating system in 31-bit mode\n");
785 	else
786 		pr_info("Linux is running natively in 31-bit mode\n");
787 	if (MACHINE_HAS_IEEE)
788 		pr_info("The hardware system has IEEE compatible "
789 			"floating point units\n");
790 	else
791 		pr_info("The hardware system has no IEEE compatible "
792 			"floating point units\n");
793 #else /* CONFIG_64BIT */
794 	if (MACHINE_IS_VM)
795 		pr_info("Linux is running as a z/VM "
796 			"guest operating system in 64-bit mode\n");
797 	else if (MACHINE_IS_KVM) {
798 		pr_info("Linux is running under KVM in 64-bit mode\n");
799 		add_preferred_console("hvc", 0, NULL);
800 		s390_virtio_console_init();
801 	} else
802 		pr_info("Linux is running natively in 64-bit mode\n");
803 #endif /* CONFIG_64BIT */
804 
805 	/* Have one command line that is parsed and saved in /proc/cmdline */
806 	/* boot_command_line has been already set up in early.c */
807 	*cmdline_p = boot_command_line;
808 
809         ROOT_DEV = Root_RAM0;
810 
811 	init_mm.start_code = PAGE_OFFSET;
812 	init_mm.end_code = (unsigned long) &_etext;
813 	init_mm.end_data = (unsigned long) &_edata;
814 	init_mm.brk = (unsigned long) &_end;
815 
816 	if (MACHINE_HAS_MVCOS)
817 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
818 	else
819 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
820 
821 	parse_early_param();
822 
823 	setup_ipl();
824 	setup_memory_end();
825 	setup_addressing_mode();
826 	setup_memory();
827 	setup_resources();
828 	setup_lowcore();
829 
830         cpu_init();
831 	__cpu_logical_map[0] = stap();
832 	s390_init_cpu_topology();
833 
834 	/*
835 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
836 	 */
837 	setup_hwcaps();
838 
839 	/*
840 	 * Create kernel page tables and switch to virtual addressing.
841 	 */
842         paging_init();
843 
844         /* Setup default console */
845 	conmode_default();
846 
847 	/* Setup zfcpdump support */
848 	setup_zfcpdump(console_devno);
849 }
850