xref: /linux/arch/s390/kernel/setup.c (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4)
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 unsigned int console_devno = -1;
78 unsigned int console_irq = -1;
79 unsigned long machine_flags;
80 unsigned long elf_hwcap = 0;
81 char elf_platform[ELF_PLATFORM_SIZE];
82 
83 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
84 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
85 static unsigned long __initdata memory_end;
86 
87 /*
88  * This is set up by the setup-routine at boot-time
89  * for S390 need to find out, what we have to setup
90  * using address 0x10400 ...
91  */
92 
93 #include <asm/setup.h>
94 
95 static struct resource code_resource = {
96 	.name  = "Kernel code",
97 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
98 };
99 
100 static struct resource data_resource = {
101 	.name = "Kernel data",
102 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
103 };
104 
105 /*
106  * cpu_init() initializes state that is per-CPU.
107  */
108 void __cpuinit cpu_init(void)
109 {
110         int addr = hard_smp_processor_id();
111 
112         /*
113          * Store processor id in lowcore (used e.g. in timer_interrupt)
114          */
115 	get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
116         S390_lowcore.cpu_data.cpu_addr = addr;
117 
118         /*
119          * Force FPU initialization:
120          */
121         clear_thread_flag(TIF_USEDFPU);
122         clear_used_math();
123 
124 	atomic_inc(&init_mm.mm_count);
125 	current->active_mm = &init_mm;
126         if (current->mm)
127                 BUG();
128         enter_lazy_tlb(&init_mm, current);
129 }
130 
131 /*
132  * condev= and conmode= setup parameter.
133  */
134 
135 static int __init condev_setup(char *str)
136 {
137 	int vdev;
138 
139 	vdev = simple_strtoul(str, &str, 0);
140 	if (vdev >= 0 && vdev < 65536) {
141 		console_devno = vdev;
142 		console_irq = -1;
143 	}
144 	return 1;
145 }
146 
147 __setup("condev=", condev_setup);
148 
149 static int __init conmode_setup(char *str)
150 {
151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
152 	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
153                 SET_CONSOLE_SCLP;
154 #endif
155 #if defined(CONFIG_TN3215_CONSOLE)
156 	if (strncmp(str, "3215", 5) == 0)
157 		SET_CONSOLE_3215;
158 #endif
159 #if defined(CONFIG_TN3270_CONSOLE)
160 	if (strncmp(str, "3270", 5) == 0)
161 		SET_CONSOLE_3270;
162 #endif
163         return 1;
164 }
165 
166 __setup("conmode=", conmode_setup);
167 
168 static void __init conmode_default(void)
169 {
170 	char query_buffer[1024];
171 	char *ptr;
172 
173         if (MACHINE_IS_VM) {
174 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
175 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
176 		ptr = strstr(query_buffer, "SUBCHANNEL =");
177 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
178 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
179 		ptr = strstr(query_buffer, "CONMODE");
180 		/*
181 		 * Set the conmode to 3215 so that the device recognition
182 		 * will set the cu_type of the console to 3215. If the
183 		 * conmode is 3270 and we don't set it back then both
184 		 * 3215 and the 3270 driver will try to access the console
185 		 * device (3215 as console and 3270 as normal tty).
186 		 */
187 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
188 		if (ptr == NULL) {
189 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
190 			SET_CONSOLE_SCLP;
191 #endif
192 			return;
193 		}
194 		if (strncmp(ptr + 8, "3270", 4) == 0) {
195 #if defined(CONFIG_TN3270_CONSOLE)
196 			SET_CONSOLE_3270;
197 #elif defined(CONFIG_TN3215_CONSOLE)
198 			SET_CONSOLE_3215;
199 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
200 			SET_CONSOLE_SCLP;
201 #endif
202 		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
203 #if defined(CONFIG_TN3215_CONSOLE)
204 			SET_CONSOLE_3215;
205 #elif defined(CONFIG_TN3270_CONSOLE)
206 			SET_CONSOLE_3270;
207 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208 			SET_CONSOLE_SCLP;
209 #endif
210 		}
211 	} else {
212 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
213 		SET_CONSOLE_SCLP;
214 #endif
215 	}
216 }
217 
218 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
219 static void __init setup_zfcpdump(unsigned int console_devno)
220 {
221 	static char str[41];
222 
223 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
224 		return;
225 	if (console_devno != -1)
226 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
227 			ipl_info.data.fcp.dev_id.devno, console_devno);
228 	else
229 		sprintf(str, " cio_ignore=all,!0.0.%04x",
230 			ipl_info.data.fcp.dev_id.devno);
231 	strcat(boot_command_line, str);
232 	console_loglevel = 2;
233 }
234 #else
235 static inline void setup_zfcpdump(unsigned int console_devno) {}
236 #endif /* CONFIG_ZFCPDUMP */
237 
238  /*
239  * Reboot, halt and power_off stubs. They just call _machine_restart,
240  * _machine_halt or _machine_power_off.
241  */
242 
243 void machine_restart(char *command)
244 {
245 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
246 		/*
247 		 * Only unblank the console if we are called in enabled
248 		 * context or a bust_spinlocks cleared the way for us.
249 		 */
250 		console_unblank();
251 	_machine_restart(command);
252 }
253 
254 void machine_halt(void)
255 {
256 	if (!in_interrupt() || oops_in_progress)
257 		/*
258 		 * Only unblank the console if we are called in enabled
259 		 * context or a bust_spinlocks cleared the way for us.
260 		 */
261 		console_unblank();
262 	_machine_halt();
263 }
264 
265 void machine_power_off(void)
266 {
267 	if (!in_interrupt() || oops_in_progress)
268 		/*
269 		 * Only unblank the console if we are called in enabled
270 		 * context or a bust_spinlocks cleared the way for us.
271 		 */
272 		console_unblank();
273 	_machine_power_off();
274 }
275 
276 /*
277  * Dummy power off function.
278  */
279 void (*pm_power_off)(void) = machine_power_off;
280 
281 static int __init early_parse_mem(char *p)
282 {
283 	memory_end = memparse(p, &p);
284 	return 0;
285 }
286 early_param("mem", early_parse_mem);
287 
288 #ifdef CONFIG_S390_SWITCH_AMODE
289 #ifdef CONFIG_PGSTE
290 unsigned int switch_amode = 1;
291 #else
292 unsigned int switch_amode = 0;
293 #endif
294 EXPORT_SYMBOL_GPL(switch_amode);
295 
296 static int set_amode_and_uaccess(unsigned long user_amode,
297 				 unsigned long user32_amode)
298 {
299 	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
300 			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
301 			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
302 #ifdef CONFIG_COMPAT
303 	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
304 			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
305 			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
306 	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
307 			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
308 			  PSW32_MASK_PSTATE;
309 #endif
310 	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
311 			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
312 
313 	if (MACHINE_HAS_MVCOS) {
314 		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
315 		return 1;
316 	} else {
317 		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
318 		return 0;
319 	}
320 }
321 
322 /*
323  * Switch kernel/user addressing modes?
324  */
325 static int __init early_parse_switch_amode(char *p)
326 {
327 	switch_amode = 1;
328 	return 0;
329 }
330 early_param("switch_amode", early_parse_switch_amode);
331 
332 #else /* CONFIG_S390_SWITCH_AMODE */
333 static inline int set_amode_and_uaccess(unsigned long user_amode,
334 					unsigned long user32_amode)
335 {
336 	return 0;
337 }
338 #endif /* CONFIG_S390_SWITCH_AMODE */
339 
340 #ifdef CONFIG_S390_EXEC_PROTECT
341 unsigned int s390_noexec = 0;
342 EXPORT_SYMBOL_GPL(s390_noexec);
343 
344 /*
345  * Enable execute protection?
346  */
347 static int __init early_parse_noexec(char *p)
348 {
349 	if (!strncmp(p, "off", 3))
350 		return 0;
351 	switch_amode = 1;
352 	s390_noexec = 1;
353 	return 0;
354 }
355 early_param("noexec", early_parse_noexec);
356 #endif /* CONFIG_S390_EXEC_PROTECT */
357 
358 static void setup_addressing_mode(void)
359 {
360 	if (s390_noexec) {
361 		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
362 					  PSW32_ASC_SECONDARY))
363 			pr_info("Execute protection active, "
364 				"mvcos available\n");
365 		else
366 			pr_info("Execute protection active, "
367 				"mvcos not available\n");
368 	} else if (switch_amode) {
369 		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
370 			pr_info("Address spaces switched, "
371 				"mvcos available\n");
372 		else
373 			pr_info("Address spaces switched, "
374 				"mvcos not available\n");
375 	}
376 #ifdef CONFIG_TRACE_IRQFLAGS
377 	sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
378 	io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
379 #endif
380 }
381 
382 static void __init
383 setup_lowcore(void)
384 {
385 	struct _lowcore *lc;
386 	int lc_pages;
387 
388 	/*
389 	 * Setup lowcore for boot cpu
390 	 */
391 	lc_pages = sizeof(void *) == 8 ? 2 : 1;
392 	lc = (struct _lowcore *)
393 		__alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
394 	memset(lc, 0, lc_pages * PAGE_SIZE);
395 	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
396 	lc->restart_psw.addr =
397 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
398 	if (switch_amode)
399 		lc->restart_psw.mask |= PSW_ASC_HOME;
400 	lc->external_new_psw.mask = psw_kernel_bits;
401 	lc->external_new_psw.addr =
402 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
403 	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
404 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
405 	lc->program_new_psw.mask = psw_kernel_bits;
406 	lc->program_new_psw.addr =
407 		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
408 	lc->mcck_new_psw.mask =
409 		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
410 	lc->mcck_new_psw.addr =
411 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
412 	lc->io_new_psw.mask = psw_kernel_bits;
413 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
414 	lc->ipl_device = S390_lowcore.ipl_device;
415 	lc->clock_comparator = -1ULL;
416 	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
417 	lc->async_stack = (unsigned long)
418 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
419 	lc->panic_stack = (unsigned long)
420 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
421 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
422 	lc->thread_info = (unsigned long) &init_thread_union;
423 #ifndef CONFIG_64BIT
424 	if (MACHINE_HAS_IEEE) {
425 		lc->extended_save_area_addr = (__u32)
426 			__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
427 		/* enable extended save area */
428 		__ctl_set_bit(14, 29);
429 	}
430 #else
431 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
432 #endif
433 	set_prefix((u32)(unsigned long) lc);
434 }
435 
436 static void __init
437 setup_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 
501 unsigned long real_memory_size;
502 EXPORT_SYMBOL_GPL(real_memory_size);
503 
504 static void __init setup_memory_end(void)
505 {
506 	unsigned long memory_size;
507 	unsigned long max_mem;
508 	int i;
509 
510 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
511 	if (ipl_info.type == IPL_TYPE_FCP_DUMP)
512 		memory_end = ZFCPDUMP_HSA_SIZE;
513 #endif
514 	memory_size = 0;
515 	memory_end &= PAGE_MASK;
516 
517 	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
518 	memory_end = min(max_mem, memory_end);
519 
520 	/*
521 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
522 	 * extra checks that HOLES_IN_ZONE would require.
523 	 */
524 	for (i = 0; i < MEMORY_CHUNKS; i++) {
525 		unsigned long start, end;
526 		struct mem_chunk *chunk;
527 		unsigned long align;
528 
529 		chunk = &memory_chunk[i];
530 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
531 		start = (chunk->addr + align - 1) & ~(align - 1);
532 		end = (chunk->addr + chunk->size) & ~(align - 1);
533 		if (start >= end)
534 			memset(chunk, 0, sizeof(*chunk));
535 		else {
536 			chunk->addr = start;
537 			chunk->size = end - start;
538 		}
539 	}
540 
541 	for (i = 0; i < MEMORY_CHUNKS; i++) {
542 		struct mem_chunk *chunk = &memory_chunk[i];
543 
544 		real_memory_size = max(real_memory_size,
545 				       chunk->addr + chunk->size);
546 		if (chunk->addr >= max_mem) {
547 			memset(chunk, 0, sizeof(*chunk));
548 			continue;
549 		}
550 		if (chunk->addr + chunk->size > max_mem)
551 			chunk->size = max_mem - chunk->addr;
552 		memory_size = max(memory_size, chunk->addr + chunk->size);
553 	}
554 	if (!memory_end)
555 		memory_end = memory_size;
556 }
557 
558 static void __init
559 setup_memory(void)
560 {
561         unsigned long bootmap_size;
562 	unsigned long start_pfn, end_pfn;
563 	int i;
564 
565 	/*
566 	 * partially used pages are not usable - thus
567 	 * we are rounding upwards:
568 	 */
569 	start_pfn = PFN_UP(__pa(&_end));
570 	end_pfn = max_pfn = PFN_DOWN(memory_end);
571 
572 #ifdef CONFIG_BLK_DEV_INITRD
573 	/*
574 	 * Move the initrd in case the bitmap of the bootmem allocater
575 	 * would overwrite it.
576 	 */
577 
578 	if (INITRD_START && INITRD_SIZE) {
579 		unsigned long bmap_size;
580 		unsigned long start;
581 
582 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
583 		bmap_size = PFN_PHYS(bmap_size);
584 
585 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
586 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
587 
588 			if (start + INITRD_SIZE > memory_end) {
589 				pr_err("initrd extends beyond end of "
590 				       "memory (0x%08lx > 0x%08lx) "
591 				       "disabling initrd\n",
592 				       start + INITRD_SIZE, memory_end);
593 				INITRD_START = INITRD_SIZE = 0;
594 			} else {
595 				pr_info("Moving initrd (0x%08lx -> "
596 					"0x%08lx, size: %ld)\n",
597 					INITRD_START, start, INITRD_SIZE);
598 				memmove((void *) start, (void *) INITRD_START,
599 					INITRD_SIZE);
600 				INITRD_START = start;
601 			}
602 		}
603 	}
604 #endif
605 
606 	/*
607 	 * Initialize the boot-time allocator
608 	 */
609 	bootmap_size = init_bootmem(start_pfn, end_pfn);
610 
611 	/*
612 	 * Register RAM areas with the bootmem allocator.
613 	 */
614 
615 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
616 		unsigned long start_chunk, end_chunk, pfn;
617 
618 		if (memory_chunk[i].type != CHUNK_READ_WRITE)
619 			continue;
620 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
621 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
622 		end_chunk = min(end_chunk, end_pfn);
623 		if (start_chunk >= end_chunk)
624 			continue;
625 		add_active_range(0, start_chunk, end_chunk);
626 		pfn = max(start_chunk, start_pfn);
627 		for (; pfn < end_chunk; pfn++)
628 			page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
629 	}
630 
631 	psw_set_key(PAGE_DEFAULT_KEY);
632 
633 	free_bootmem_with_active_regions(0, max_pfn);
634 
635 	/*
636 	 * Reserve memory used for lowcore/command line/kernel image.
637 	 */
638 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
639 	reserve_bootmem((unsigned long)_stext,
640 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
641 			BOOTMEM_DEFAULT);
642 	/*
643 	 * Reserve the bootmem bitmap itself as well. We do this in two
644 	 * steps (first step was init_bootmem()) because this catches
645 	 * the (very unlikely) case of us accidentally initializing the
646 	 * bootmem allocator with an invalid RAM area.
647 	 */
648 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
649 			BOOTMEM_DEFAULT);
650 
651 #ifdef CONFIG_BLK_DEV_INITRD
652 	if (INITRD_START && INITRD_SIZE) {
653 		if (INITRD_START + INITRD_SIZE <= memory_end) {
654 			reserve_bootmem(INITRD_START, INITRD_SIZE,
655 					BOOTMEM_DEFAULT);
656 			initrd_start = INITRD_START;
657 			initrd_end = initrd_start + INITRD_SIZE;
658 		} else {
659 			pr_err("initrd extends beyond end of "
660 			       "memory (0x%08lx > 0x%08lx) "
661 			       "disabling initrd\n",
662 			       initrd_start + INITRD_SIZE, memory_end);
663 			initrd_start = initrd_end = 0;
664 		}
665 	}
666 #endif
667 }
668 
669 /*
670  * Setup hardware capabilities.
671  */
672 static void __init setup_hwcaps(void)
673 {
674 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
675 	struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
676 	unsigned long long facility_list_extended;
677 	unsigned int facility_list;
678 	int i;
679 
680 	facility_list = stfl();
681 	/*
682 	 * The store facility list bits numbers as found in the principles
683 	 * of operation are numbered with bit 1UL<<31 as number 0 to
684 	 * bit 1UL<<0 as number 31.
685 	 *   Bit 0: instructions named N3, "backported" to esa-mode
686 	 *   Bit 2: z/Architecture mode is active
687 	 *   Bit 7: the store-facility-list-extended facility is installed
688 	 *   Bit 17: the message-security assist is installed
689 	 *   Bit 19: the long-displacement facility is installed
690 	 *   Bit 21: the extended-immediate facility is installed
691 	 * These get translated to:
692 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
693 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
694 	 *   HWCAP_S390_LDISP bit 4, and HWCAP_S390_EIMM bit 5.
695 	 */
696 	for (i = 0; i < 6; i++)
697 		if (facility_list & (1UL << (31 - stfl_bits[i])))
698 			elf_hwcap |= 1UL << i;
699 
700 	/*
701 	 * Check for additional facilities with store-facility-list-extended.
702 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
703 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
704 	 * as stored by stfl, bits 32-xxx contain additional facilities.
705 	 * How many facility words are stored depends on the number of
706 	 * doublewords passed to the instruction. The additional facilites
707 	 * are:
708 	 *   Bit 43: decimal floating point facility is installed
709 	 * translated to:
710 	 *   HWCAP_S390_DFP bit 6.
711 	 */
712 	if ((elf_hwcap & (1UL << 2)) &&
713 	    __stfle(&facility_list_extended, 1) > 0) {
714 		if (facility_list_extended & (1ULL << (64 - 43)))
715 			elf_hwcap |= 1UL << 6;
716 	}
717 
718 	if (MACHINE_HAS_HPAGE)
719 		elf_hwcap |= 1UL << 7;
720 
721 	switch (cpuinfo->cpu_id.machine) {
722 	case 0x9672:
723 #if !defined(CONFIG_64BIT)
724 	default:	/* Use "g5" as default for 31 bit kernels. */
725 #endif
726 		strcpy(elf_platform, "g5");
727 		break;
728 	case 0x2064:
729 	case 0x2066:
730 #if defined(CONFIG_64BIT)
731 	default:	/* Use "z900" as default for 64 bit kernels. */
732 #endif
733 		strcpy(elf_platform, "z900");
734 		break;
735 	case 0x2084:
736 	case 0x2086:
737 		strcpy(elf_platform, "z990");
738 		break;
739 	case 0x2094:
740 	case 0x2096:
741 		strcpy(elf_platform, "z9-109");
742 		break;
743 	case 0x2097:
744 	case 0x2098:
745 		strcpy(elf_platform, "z10");
746 		break;
747 	}
748 }
749 
750 /*
751  * Setup function called from init/main.c just after the banner
752  * was printed.
753  */
754 
755 void __init
756 setup_arch(char **cmdline_p)
757 {
758 	/* set up preferred console */
759 	add_preferred_console("ttyS", 0, NULL);
760 
761         /*
762          * print what head.S has found out about the machine
763          */
764 #ifndef CONFIG_64BIT
765 	if (MACHINE_IS_VM)
766 		pr_info("Linux is running as a z/VM "
767 			"guest operating system in 31-bit mode\n");
768 	else
769 		pr_info("Linux is running natively in 31-bit mode\n");
770 	if (MACHINE_HAS_IEEE)
771 		pr_info("The hardware system has IEEE compatible "
772 			"floating point units\n");
773 	else
774 		pr_info("The hardware system has no IEEE compatible "
775 			"floating point units\n");
776 #else /* CONFIG_64BIT */
777 	if (MACHINE_IS_VM)
778 		pr_info("Linux is running as a z/VM "
779 			"guest operating system in 64-bit mode\n");
780 	else if (MACHINE_IS_KVM) {
781 		pr_info("Linux is running under KVM in 64-bit mode\n");
782 		add_preferred_console("hvc", 0, NULL);
783 		s390_virtio_console_init();
784 	} else
785 		pr_info("Linux is running natively in 64-bit mode\n");
786 #endif /* CONFIG_64BIT */
787 
788 	/* Have one command line that is parsed and saved in /proc/cmdline */
789 	/* boot_command_line has been already set up in early.c */
790 	*cmdline_p = boot_command_line;
791 
792         ROOT_DEV = Root_RAM0;
793 
794 	init_mm.start_code = PAGE_OFFSET;
795 	init_mm.end_code = (unsigned long) &_etext;
796 	init_mm.end_data = (unsigned long) &_edata;
797 	init_mm.brk = (unsigned long) &_end;
798 
799 	if (MACHINE_HAS_MVCOS)
800 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
801 	else
802 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
803 
804 	parse_early_param();
805 
806 	setup_ipl();
807 	setup_memory_end();
808 	setup_addressing_mode();
809 	setup_memory();
810 	setup_resources();
811 	setup_lowcore();
812 
813         cpu_init();
814         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
815 	s390_init_cpu_topology();
816 
817 	/*
818 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
819 	 */
820 	setup_hwcaps();
821 
822 	/*
823 	 * Create kernel page tables and switch to virtual addressing.
824 	 */
825         paging_init();
826 
827         /* Setup default console */
828 	conmode_default();
829 
830 	/* Setup zfcpdump support */
831 	setup_zfcpdump(console_devno);
832 }
833