xref: /linux/arch/s390/kernel/setup.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
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 
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 elf_hwcap = 0;
86 char elf_platform[ELF_PLATFORM_SIZE];
87 
88 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
89 
90 int __initdata memory_end_set;
91 unsigned long __initdata memory_end;
92 
93 /* An array with a pointer to the lowcore of every CPU. */
94 struct _lowcore *lowcore_ptr[NR_CPUS];
95 EXPORT_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 
105 static struct resource code_resource = {
106 	.name  = "Kernel code",
107 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
108 };
109 
110 static 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 
119 static 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 
133 static 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 
143 static 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 
163 static 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
214 static 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
230 static 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 
238 void 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 
249 void 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 
260 void 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  */
274 void (*pm_power_off)(void) = machine_power_off;
275 
276 static int __init early_parse_mem(char *p)
277 {
278 	memory_end = memparse(p, &p);
279 	memory_end_set = 1;
280 	return 0;
281 }
282 early_param("mem", early_parse_mem);
283 
284 unsigned int user_mode = HOME_SPACE_MODE;
285 EXPORT_SYMBOL_GPL(user_mode);
286 
287 static 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  */
316 static 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 }
322 early_param("switch_amode", early_parse_switch_amode);
323 
324 static 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 }
338 early_param("user_mode", early_parse_user_mode);
339 
340 #ifdef CONFIG_S390_EXEC_PROTECT
341 /*
342  * Enable execute protection?
343  */
344 static 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 }
351 early_param("noexec", early_parse_noexec);
352 #endif /* CONFIG_S390_EXEC_PROTECT */
353 
354 static 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 
374 static void __init
375 setup_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 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
413 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
414 	       MAX_FACILITY_BIT/8);
415 #ifndef CONFIG_64BIT
416 	if (MACHINE_HAS_IEEE) {
417 		lc->extended_save_area_addr = (__u32)
418 			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
419 		/* enable extended save area */
420 		__ctl_set_bit(14, 29);
421 	}
422 #else
423 	lc->cmf_hpp = -1ULL;
424 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
425 #endif
426 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
427 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
428 	lc->exit_timer = S390_lowcore.exit_timer;
429 	lc->user_timer = S390_lowcore.user_timer;
430 	lc->system_timer = S390_lowcore.system_timer;
431 	lc->steal_timer = S390_lowcore.steal_timer;
432 	lc->last_update_timer = S390_lowcore.last_update_timer;
433 	lc->last_update_clock = S390_lowcore.last_update_clock;
434 	lc->ftrace_func = S390_lowcore.ftrace_func;
435 	set_prefix((u32)(unsigned long) lc);
436 	lowcore_ptr[0] = lc;
437 }
438 
439 static void __init
440 setup_resources(void)
441 {
442 	struct resource *res, *sub_res;
443 	int i;
444 
445 	code_resource.start = (unsigned long) &_text;
446 	code_resource.end = (unsigned long) &_etext - 1;
447 	data_resource.start = (unsigned long) &_etext;
448 	data_resource.end = (unsigned long) &_edata - 1;
449 
450 	for (i = 0; i < MEMORY_CHUNKS; i++) {
451 		if (!memory_chunk[i].size)
452 			continue;
453 		res = alloc_bootmem_low(sizeof(struct resource));
454 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
455 		switch (memory_chunk[i].type) {
456 		case CHUNK_READ_WRITE:
457 			res->name = "System RAM";
458 			break;
459 		case CHUNK_READ_ONLY:
460 			res->name = "System ROM";
461 			res->flags |= IORESOURCE_READONLY;
462 			break;
463 		default:
464 			res->name = "reserved";
465 		}
466 		res->start = memory_chunk[i].addr;
467 		res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
468 		request_resource(&iomem_resource, res);
469 
470 		if (code_resource.start >= res->start  &&
471 			code_resource.start <= res->end &&
472 			code_resource.end > res->end) {
473 			sub_res = alloc_bootmem_low(sizeof(struct resource));
474 			memcpy(sub_res, &code_resource,
475 				sizeof(struct resource));
476 			sub_res->end = res->end;
477 			code_resource.start = res->end + 1;
478 			request_resource(res, sub_res);
479 		}
480 
481 		if (code_resource.start >= res->start &&
482 			code_resource.start <= res->end &&
483 			code_resource.end <= res->end)
484 			request_resource(res, &code_resource);
485 
486 		if (data_resource.start >= res->start &&
487 			data_resource.start <= res->end &&
488 			data_resource.end > res->end) {
489 			sub_res = alloc_bootmem_low(sizeof(struct resource));
490 			memcpy(sub_res, &data_resource,
491 				sizeof(struct resource));
492 			sub_res->end = res->end;
493 			data_resource.start = res->end + 1;
494 			request_resource(res, sub_res);
495 		}
496 
497 		if (data_resource.start >= res->start &&
498 			data_resource.start <= res->end &&
499 			data_resource.end <= res->end)
500 			request_resource(res, &data_resource);
501 	}
502 }
503 
504 unsigned long real_memory_size;
505 EXPORT_SYMBOL_GPL(real_memory_size);
506 
507 static void __init setup_memory_end(void)
508 {
509 	unsigned long memory_size;
510 	unsigned long max_mem;
511 	int i;
512 
513 #ifdef CONFIG_ZFCPDUMP
514 	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
515 		memory_end = ZFCPDUMP_HSA_SIZE;
516 		memory_end_set = 1;
517 	}
518 #endif
519 	memory_size = 0;
520 	memory_end &= PAGE_MASK;
521 
522 	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
523 	memory_end = min(max_mem, memory_end);
524 
525 	/*
526 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
527 	 * extra checks that HOLES_IN_ZONE would require.
528 	 */
529 	for (i = 0; i < MEMORY_CHUNKS; i++) {
530 		unsigned long start, end;
531 		struct mem_chunk *chunk;
532 		unsigned long align;
533 
534 		chunk = &memory_chunk[i];
535 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
536 		start = (chunk->addr + align - 1) & ~(align - 1);
537 		end = (chunk->addr + chunk->size) & ~(align - 1);
538 		if (start >= end)
539 			memset(chunk, 0, sizeof(*chunk));
540 		else {
541 			chunk->addr = start;
542 			chunk->size = end - start;
543 		}
544 	}
545 
546 	for (i = 0; i < MEMORY_CHUNKS; i++) {
547 		struct mem_chunk *chunk = &memory_chunk[i];
548 
549 		real_memory_size = max(real_memory_size,
550 				       chunk->addr + chunk->size);
551 		if (chunk->addr >= max_mem) {
552 			memset(chunk, 0, sizeof(*chunk));
553 			continue;
554 		}
555 		if (chunk->addr + chunk->size > max_mem)
556 			chunk->size = max_mem - chunk->addr;
557 		memory_size = max(memory_size, chunk->addr + chunk->size);
558 	}
559 	if (!memory_end)
560 		memory_end = memory_size;
561 }
562 
563 static void __init
564 setup_memory(void)
565 {
566         unsigned long bootmap_size;
567 	unsigned long start_pfn, end_pfn;
568 	int i;
569 
570 	/*
571 	 * partially used pages are not usable - thus
572 	 * we are rounding upwards:
573 	 */
574 	start_pfn = PFN_UP(__pa(&_end));
575 	end_pfn = max_pfn = PFN_DOWN(memory_end);
576 
577 #ifdef CONFIG_BLK_DEV_INITRD
578 	/*
579 	 * Move the initrd in case the bitmap of the bootmem allocater
580 	 * would overwrite it.
581 	 */
582 
583 	if (INITRD_START && INITRD_SIZE) {
584 		unsigned long bmap_size;
585 		unsigned long start;
586 
587 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
588 		bmap_size = PFN_PHYS(bmap_size);
589 
590 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
591 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
592 
593 			if (start + INITRD_SIZE > memory_end) {
594 				pr_err("initrd extends beyond end of "
595 				       "memory (0x%08lx > 0x%08lx) "
596 				       "disabling initrd\n",
597 				       start + INITRD_SIZE, memory_end);
598 				INITRD_START = INITRD_SIZE = 0;
599 			} else {
600 				pr_info("Moving initrd (0x%08lx -> "
601 					"0x%08lx, size: %ld)\n",
602 					INITRD_START, start, INITRD_SIZE);
603 				memmove((void *) start, (void *) INITRD_START,
604 					INITRD_SIZE);
605 				INITRD_START = start;
606 			}
607 		}
608 	}
609 #endif
610 
611 	/*
612 	 * Initialize the boot-time allocator
613 	 */
614 	bootmap_size = init_bootmem(start_pfn, end_pfn);
615 
616 	/*
617 	 * Register RAM areas with the bootmem allocator.
618 	 */
619 
620 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
621 		unsigned long start_chunk, end_chunk, pfn;
622 
623 		if (memory_chunk[i].type != CHUNK_READ_WRITE)
624 			continue;
625 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
626 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
627 		end_chunk = min(end_chunk, end_pfn);
628 		if (start_chunk >= end_chunk)
629 			continue;
630 		add_active_range(0, start_chunk, end_chunk);
631 		pfn = max(start_chunk, start_pfn);
632 		for (; pfn < end_chunk; pfn++)
633 			page_set_storage_key(PFN_PHYS(pfn),
634 					     PAGE_DEFAULT_KEY, 0);
635 	}
636 
637 	psw_set_key(PAGE_DEFAULT_KEY);
638 
639 	free_bootmem_with_active_regions(0, max_pfn);
640 
641 	/*
642 	 * Reserve memory used for lowcore/command line/kernel image.
643 	 */
644 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
645 	reserve_bootmem((unsigned long)_stext,
646 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
647 			BOOTMEM_DEFAULT);
648 	/*
649 	 * Reserve the bootmem bitmap itself as well. We do this in two
650 	 * steps (first step was init_bootmem()) because this catches
651 	 * the (very unlikely) case of us accidentally initializing the
652 	 * bootmem allocator with an invalid RAM area.
653 	 */
654 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
655 			BOOTMEM_DEFAULT);
656 
657 #ifdef CONFIG_BLK_DEV_INITRD
658 	if (INITRD_START && INITRD_SIZE) {
659 		if (INITRD_START + INITRD_SIZE <= memory_end) {
660 			reserve_bootmem(INITRD_START, INITRD_SIZE,
661 					BOOTMEM_DEFAULT);
662 			initrd_start = INITRD_START;
663 			initrd_end = initrd_start + INITRD_SIZE;
664 		} else {
665 			pr_err("initrd extends beyond end of "
666 			       "memory (0x%08lx > 0x%08lx) "
667 			       "disabling initrd\n",
668 			       initrd_start + INITRD_SIZE, memory_end);
669 			initrd_start = initrd_end = 0;
670 		}
671 	}
672 #endif
673 }
674 
675 /*
676  * Setup hardware capabilities.
677  */
678 static void __init setup_hwcaps(void)
679 {
680 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
681 	struct cpuid cpu_id;
682 	int i;
683 
684 	/*
685 	 * The store facility list bits numbers as found in the principles
686 	 * of operation are numbered with bit 1UL<<31 as number 0 to
687 	 * bit 1UL<<0 as number 31.
688 	 *   Bit 0: instructions named N3, "backported" to esa-mode
689 	 *   Bit 2: z/Architecture mode is active
690 	 *   Bit 7: the store-facility-list-extended facility is installed
691 	 *   Bit 17: the message-security assist is installed
692 	 *   Bit 19: the long-displacement facility is installed
693 	 *   Bit 21: the extended-immediate facility is installed
694 	 *   Bit 22: extended-translation facility 3 is installed
695 	 *   Bit 30: extended-translation facility 3 enhancement facility
696 	 * These get translated to:
697 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
698 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
699 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
700 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
701 	 */
702 	for (i = 0; i < 6; i++)
703 		if (test_facility(stfl_bits[i]))
704 			elf_hwcap |= 1UL << i;
705 
706 	if (test_facility(22) && test_facility(30))
707 		elf_hwcap |= HWCAP_S390_ETF3EH;
708 
709 	/*
710 	 * Check for additional facilities with store-facility-list-extended.
711 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
712 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
713 	 * as stored by stfl, bits 32-xxx contain additional facilities.
714 	 * How many facility words are stored depends on the number of
715 	 * doublewords passed to the instruction. The additional facilites
716 	 * are:
717 	 *   Bit 42: decimal floating point facility is installed
718 	 *   Bit 44: perform floating point operation facility is installed
719 	 * translated to:
720 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
721 	 */
722 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
723 		elf_hwcap |= HWCAP_S390_DFP;
724 
725 	/*
726 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
727 	 */
728 	if (MACHINE_HAS_HPAGE)
729 		elf_hwcap |= HWCAP_S390_HPAGE;
730 
731 	/*
732 	 * 64-bit register support for 31-bit processes
733 	 * HWCAP_S390_HIGH_GPRS is bit 9.
734 	 */
735 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
736 
737 	get_cpu_id(&cpu_id);
738 	switch (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 	case 0x2817:
765 		strcpy(elf_platform, "z196");
766 		break;
767 	}
768 }
769 
770 /*
771  * Setup function called from init/main.c just after the banner
772  * was printed.
773  */
774 
775 void __init
776 setup_arch(char **cmdline_p)
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 if (MACHINE_IS_LPAR)
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 	else if (MACHINE_IS_LPAR)
800 		pr_info("Linux is running natively in 64-bit mode\n");
801 #endif /* CONFIG_64BIT */
802 
803 	/* Have one command line that is parsed and saved in /proc/cmdline */
804 	/* boot_command_line has been already set up in early.c */
805 	*cmdline_p = boot_command_line;
806 
807         ROOT_DEV = Root_RAM0;
808 
809 	init_mm.start_code = PAGE_OFFSET;
810 	init_mm.end_code = (unsigned long) &_etext;
811 	init_mm.end_data = (unsigned long) &_edata;
812 	init_mm.brk = (unsigned long) &_end;
813 
814 	if (MACHINE_HAS_MVCOS)
815 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
816 	else
817 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
818 
819 	parse_early_param();
820 
821 	setup_ipl();
822 	setup_memory_end();
823 	setup_addressing_mode();
824 	setup_memory();
825 	setup_resources();
826 	setup_lowcore();
827 
828         cpu_init();
829 	s390_init_cpu_topology();
830 
831 	/*
832 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
833 	 */
834 	setup_hwcaps();
835 
836 	/*
837 	 * Create kernel page tables and switch to virtual addressing.
838 	 */
839         paging_init();
840 
841         /* Setup default console */
842 	conmode_default();
843 	set_preferred_console();
844 
845 	/* Setup zfcpdump support */
846 	setup_zfcpdump(console_devno);
847 }
848