xref: /linux/arch/s390/kernel/setup.c (revision c39b9fd728d8173ecda993524089fbc38211a17f)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 1999, 2012
4  *    Author(s): Hartmut Penner (hp@de.ibm.com),
5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  *  Derived from "arch/i386/kernel/setup.c"
8  *    Copyright (C) 1995, Linus Torvalds
9  */
10 
11 /*
12  * This file handles the architecture-dependent parts of initialization
13  */
14 
15 #define KMSG_COMPONENT "setup"
16 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
17 
18 #include <linux/errno.h>
19 #include <linux/export.h>
20 #include <linux/sched.h>
21 #include <linux/kernel.h>
22 #include <linux/memblock.h>
23 #include <linux/mm.h>
24 #include <linux/stddef.h>
25 #include <linux/unistd.h>
26 #include <linux/ptrace.h>
27 #include <linux/user.h>
28 #include <linux/tty.h>
29 #include <linux/ioport.h>
30 #include <linux/delay.h>
31 #include <linux/init.h>
32 #include <linux/initrd.h>
33 #include <linux/bootmem.h>
34 #include <linux/root_dev.h>
35 #include <linux/console.h>
36 #include <linux/kernel_stat.h>
37 #include <linux/device.h>
38 #include <linux/notifier.h>
39 #include <linux/pfn.h>
40 #include <linux/ctype.h>
41 #include <linux/reboot.h>
42 #include <linux/topology.h>
43 #include <linux/ftrace.h>
44 #include <linux/kexec.h>
45 #include <linux/crash_dump.h>
46 #include <linux/memory.h>
47 #include <linux/compat.h>
48 
49 #include <asm/ipl.h>
50 #include <asm/uaccess.h>
51 #include <asm/facility.h>
52 #include <asm/smp.h>
53 #include <asm/mmu_context.h>
54 #include <asm/cpcmd.h>
55 #include <asm/lowcore.h>
56 #include <asm/irq.h>
57 #include <asm/page.h>
58 #include <asm/ptrace.h>
59 #include <asm/sections.h>
60 #include <asm/ebcdic.h>
61 #include <asm/kvm_virtio.h>
62 #include <asm/diag.h>
63 #include <asm/os_info.h>
64 #include <asm/sclp.h>
65 #include "entry.h"
66 
67 long psw_kernel_bits	= PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
68 			  PSW_MASK_EA | PSW_MASK_BA;
69 long psw_user_bits	= PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
70 			  PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
71 			  PSW_MASK_PSTATE | PSW_ASC_HOME;
72 
73 /*
74  * User copy operations.
75  */
76 struct uaccess_ops uaccess;
77 EXPORT_SYMBOL(uaccess);
78 
79 /*
80  * Machine setup..
81  */
82 unsigned int console_mode = 0;
83 EXPORT_SYMBOL(console_mode);
84 
85 unsigned int console_devno = -1;
86 EXPORT_SYMBOL(console_devno);
87 
88 unsigned int console_irq = -1;
89 EXPORT_SYMBOL(console_irq);
90 
91 unsigned long elf_hwcap = 0;
92 char elf_platform[ELF_PLATFORM_SIZE];
93 
94 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
95 
96 int __initdata memory_end_set;
97 unsigned long __initdata memory_end;
98 
99 unsigned long VMALLOC_START;
100 EXPORT_SYMBOL(VMALLOC_START);
101 
102 unsigned long VMALLOC_END;
103 EXPORT_SYMBOL(VMALLOC_END);
104 
105 struct page *vmemmap;
106 EXPORT_SYMBOL(vmemmap);
107 
108 #ifdef CONFIG_64BIT
109 unsigned long MODULES_VADDR;
110 unsigned long MODULES_END;
111 #endif
112 
113 /* An array with a pointer to the lowcore of every CPU. */
114 struct _lowcore *lowcore_ptr[NR_CPUS];
115 EXPORT_SYMBOL(lowcore_ptr);
116 
117 /*
118  * This is set up by the setup-routine at boot-time
119  * for S390 need to find out, what we have to setup
120  * using address 0x10400 ...
121  */
122 
123 #include <asm/setup.h>
124 
125 /*
126  * condev= and conmode= setup parameter.
127  */
128 
129 static int __init condev_setup(char *str)
130 {
131 	int vdev;
132 
133 	vdev = simple_strtoul(str, &str, 0);
134 	if (vdev >= 0 && vdev < 65536) {
135 		console_devno = vdev;
136 		console_irq = -1;
137 	}
138 	return 1;
139 }
140 
141 __setup("condev=", condev_setup);
142 
143 static void __init set_preferred_console(void)
144 {
145 	if (MACHINE_IS_KVM) {
146 		if (sclp_has_vt220())
147 			add_preferred_console("ttyS", 1, NULL);
148 		else if (sclp_has_linemode())
149 			add_preferred_console("ttyS", 0, NULL);
150 		else
151 			add_preferred_console("hvc", 0, NULL);
152 	} else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
153 		add_preferred_console("ttyS", 0, NULL);
154 	else if (CONSOLE_IS_3270)
155 		add_preferred_console("tty3270", 0, NULL);
156 }
157 
158 static int __init conmode_setup(char *str)
159 {
160 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
161 	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
162                 SET_CONSOLE_SCLP;
163 #endif
164 #if defined(CONFIG_TN3215_CONSOLE)
165 	if (strncmp(str, "3215", 5) == 0)
166 		SET_CONSOLE_3215;
167 #endif
168 #if defined(CONFIG_TN3270_CONSOLE)
169 	if (strncmp(str, "3270", 5) == 0)
170 		SET_CONSOLE_3270;
171 #endif
172 	set_preferred_console();
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 (OLDMEM_BASE)
236 		return;
237 	if (console_devno != -1)
238 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
239 			ipl_info.data.fcp.dev_id.devno, console_devno);
240 	else
241 		sprintf(str, " cio_ignore=all,!0.0.%04x",
242 			ipl_info.data.fcp.dev_id.devno);
243 	strcat(boot_command_line, str);
244 	console_loglevel = 2;
245 }
246 #else
247 static inline void setup_zfcpdump(unsigned int console_devno) {}
248 #endif /* CONFIG_ZFCPDUMP */
249 
250  /*
251  * Reboot, halt and power_off stubs. They just call _machine_restart,
252  * _machine_halt or _machine_power_off.
253  */
254 
255 void machine_restart(char *command)
256 {
257 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
258 		/*
259 		 * Only unblank the console if we are called in enabled
260 		 * context or a bust_spinlocks cleared the way for us.
261 		 */
262 		console_unblank();
263 	_machine_restart(command);
264 }
265 
266 void machine_halt(void)
267 {
268 	if (!in_interrupt() || oops_in_progress)
269 		/*
270 		 * Only unblank the console if we are called in enabled
271 		 * context or a bust_spinlocks cleared the way for us.
272 		 */
273 		console_unblank();
274 	_machine_halt();
275 }
276 
277 void machine_power_off(void)
278 {
279 	if (!in_interrupt() || oops_in_progress)
280 		/*
281 		 * Only unblank the console if we are called in enabled
282 		 * context or a bust_spinlocks cleared the way for us.
283 		 */
284 		console_unblank();
285 	_machine_power_off();
286 }
287 
288 /*
289  * Dummy power off function.
290  */
291 void (*pm_power_off)(void) = machine_power_off;
292 EXPORT_SYMBOL_GPL(pm_power_off);
293 
294 static int __init early_parse_mem(char *p)
295 {
296 	memory_end = memparse(p, &p);
297 	memory_end_set = 1;
298 	return 0;
299 }
300 early_param("mem", early_parse_mem);
301 
302 static int __init parse_vmalloc(char *arg)
303 {
304 	if (!arg)
305 		return -EINVAL;
306 	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
307 	return 0;
308 }
309 early_param("vmalloc", parse_vmalloc);
310 
311 unsigned int s390_user_mode = PRIMARY_SPACE_MODE;
312 EXPORT_SYMBOL_GPL(s390_user_mode);
313 
314 static void __init set_user_mode_primary(void)
315 {
316 	psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
317 	psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
318 #ifdef CONFIG_COMPAT
319 	psw32_user_bits =
320 		(psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
321 #endif
322 	uaccess = MACHINE_HAS_MVCOS ? uaccess_mvcos_switch : uaccess_pt;
323 }
324 
325 static int __init early_parse_user_mode(char *p)
326 {
327 	if (p && strcmp(p, "primary") == 0)
328 		s390_user_mode = PRIMARY_SPACE_MODE;
329 	else if (!p || strcmp(p, "home") == 0)
330 		s390_user_mode = HOME_SPACE_MODE;
331 	else
332 		return 1;
333 	return 0;
334 }
335 early_param("user_mode", early_parse_user_mode);
336 
337 static void __init setup_addressing_mode(void)
338 {
339 	if (s390_user_mode != PRIMARY_SPACE_MODE)
340 		return;
341 	set_user_mode_primary();
342 	if (MACHINE_HAS_MVCOS)
343 		pr_info("Address spaces switched, mvcos available\n");
344 	else
345 		pr_info("Address spaces switched, mvcos not available\n");
346 }
347 
348 void *restart_stack __attribute__((__section__(".data")));
349 
350 static void __init setup_lowcore(void)
351 {
352 	struct _lowcore *lc;
353 
354 	/*
355 	 * Setup lowcore for boot cpu
356 	 */
357 	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
358 	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
359 	lc->restart_psw.mask = psw_kernel_bits;
360 	lc->restart_psw.addr =
361 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
362 	lc->external_new_psw.mask = psw_kernel_bits |
363 		PSW_MASK_DAT | PSW_MASK_MCHECK;
364 	lc->external_new_psw.addr =
365 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
366 	lc->svc_new_psw.mask = psw_kernel_bits |
367 		PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
368 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
369 	lc->program_new_psw.mask = psw_kernel_bits |
370 		PSW_MASK_DAT | PSW_MASK_MCHECK;
371 	lc->program_new_psw.addr =
372 		PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
373 	lc->mcck_new_psw.mask = psw_kernel_bits;
374 	lc->mcck_new_psw.addr =
375 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
376 	lc->io_new_psw.mask = psw_kernel_bits |
377 		PSW_MASK_DAT | PSW_MASK_MCHECK;
378 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
379 	lc->clock_comparator = -1ULL;
380 	lc->kernel_stack = ((unsigned long) &init_thread_union)
381 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
382 	lc->async_stack = (unsigned long)
383 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0)
384 		+ ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
385 	lc->panic_stack = (unsigned long)
386 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0)
387 		+ PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
388 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
389 	lc->thread_info = (unsigned long) &init_thread_union;
390 	lc->machine_flags = S390_lowcore.machine_flags;
391 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
392 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
393 	       MAX_FACILITY_BIT/8);
394 #ifndef CONFIG_64BIT
395 	if (MACHINE_HAS_IEEE) {
396 		lc->extended_save_area_addr = (__u32)
397 			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
398 		/* enable extended save area */
399 		__ctl_set_bit(14, 29);
400 	}
401 #else
402 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
403 #endif
404 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
405 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
406 	lc->exit_timer = S390_lowcore.exit_timer;
407 	lc->user_timer = S390_lowcore.user_timer;
408 	lc->system_timer = S390_lowcore.system_timer;
409 	lc->steal_timer = S390_lowcore.steal_timer;
410 	lc->last_update_timer = S390_lowcore.last_update_timer;
411 	lc->last_update_clock = S390_lowcore.last_update_clock;
412 	lc->ftrace_func = S390_lowcore.ftrace_func;
413 
414 	restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
415 	restart_stack += ASYNC_SIZE;
416 
417 	/*
418 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
419 	 * restart data to the absolute zero lowcore. This is necesary if
420 	 * PSW restart is done on an offline CPU that has lowcore zero.
421 	 */
422 	lc->restart_stack = (unsigned long) restart_stack;
423 	lc->restart_fn = (unsigned long) do_restart;
424 	lc->restart_data = 0;
425 	lc->restart_source = -1UL;
426 
427 	/* Setup absolute zero lowcore */
428 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
429 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
430 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
431 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
432 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
433 
434 	set_prefix((u32)(unsigned long) lc);
435 	lowcore_ptr[0] = lc;
436 }
437 
438 static struct resource code_resource = {
439 	.name  = "Kernel code",
440 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
441 };
442 
443 static struct resource data_resource = {
444 	.name = "Kernel data",
445 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
446 };
447 
448 static struct resource bss_resource = {
449 	.name = "Kernel bss",
450 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
451 };
452 
453 static struct resource __initdata *standard_resources[] = {
454 	&code_resource,
455 	&data_resource,
456 	&bss_resource,
457 };
458 
459 static void __init setup_resources(void)
460 {
461 	struct resource *res, *std_res, *sub_res;
462 	int i, j;
463 
464 	code_resource.start = (unsigned long) &_text;
465 	code_resource.end = (unsigned long) &_etext - 1;
466 	data_resource.start = (unsigned long) &_etext;
467 	data_resource.end = (unsigned long) &_edata - 1;
468 	bss_resource.start = (unsigned long) &__bss_start;
469 	bss_resource.end = (unsigned long) &__bss_stop - 1;
470 
471 	for (i = 0; i < MEMORY_CHUNKS; i++) {
472 		if (!memory_chunk[i].size)
473 			continue;
474 		if (memory_chunk[i].type == CHUNK_OLDMEM ||
475 		    memory_chunk[i].type == CHUNK_CRASHK)
476 			continue;
477 		res = alloc_bootmem_low(sizeof(*res));
478 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
479 		switch (memory_chunk[i].type) {
480 		case CHUNK_READ_WRITE:
481 		case CHUNK_CRASHK:
482 			res->name = "System RAM";
483 			break;
484 		case CHUNK_READ_ONLY:
485 			res->name = "System ROM";
486 			res->flags |= IORESOURCE_READONLY;
487 			break;
488 		default:
489 			res->name = "reserved";
490 		}
491 		res->start = memory_chunk[i].addr;
492 		res->end = res->start + memory_chunk[i].size - 1;
493 		request_resource(&iomem_resource, res);
494 
495 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
496 			std_res = standard_resources[j];
497 			if (std_res->start < res->start ||
498 			    std_res->start > res->end)
499 				continue;
500 			if (std_res->end > res->end) {
501 				sub_res = alloc_bootmem_low(sizeof(*sub_res));
502 				*sub_res = *std_res;
503 				sub_res->end = res->end;
504 				std_res->start = res->end + 1;
505 				request_resource(res, sub_res);
506 			} else {
507 				request_resource(res, std_res);
508 			}
509 		}
510 	}
511 }
512 
513 unsigned long real_memory_size;
514 EXPORT_SYMBOL_GPL(real_memory_size);
515 
516 static void __init setup_memory_end(void)
517 {
518 	unsigned long vmax, vmalloc_size, tmp;
519 	int i;
520 
521 
522 #ifdef CONFIG_ZFCPDUMP
523 	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
524 		memory_end = ZFCPDUMP_HSA_SIZE;
525 		memory_end_set = 1;
526 	}
527 #endif
528 	real_memory_size = 0;
529 	memory_end &= PAGE_MASK;
530 
531 	/*
532 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
533 	 * extra checks that HOLES_IN_ZONE would require.
534 	 */
535 	for (i = 0; i < MEMORY_CHUNKS; i++) {
536 		unsigned long start, end;
537 		struct mem_chunk *chunk;
538 		unsigned long align;
539 
540 		chunk = &memory_chunk[i];
541 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
542 		start = (chunk->addr + align - 1) & ~(align - 1);
543 		end = (chunk->addr + chunk->size) & ~(align - 1);
544 		if (start >= end)
545 			memset(chunk, 0, sizeof(*chunk));
546 		else {
547 			chunk->addr = start;
548 			chunk->size = end - start;
549 		}
550 		real_memory_size = max(real_memory_size,
551 				       chunk->addr + chunk->size);
552 	}
553 
554 	/* Choose kernel address space layout: 2, 3, or 4 levels. */
555 #ifdef CONFIG_64BIT
556 	vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
557 	tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
558 	tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
559 	if (tmp <= (1UL << 42))
560 		vmax = 1UL << 42;	/* 3-level kernel page table */
561 	else
562 		vmax = 1UL << 53;	/* 4-level kernel page table */
563 	/* module area is at the end of the kernel address space. */
564 	MODULES_END = vmax;
565 	MODULES_VADDR = MODULES_END - MODULES_LEN;
566 	VMALLOC_END = MODULES_VADDR;
567 #else
568 	vmalloc_size = VMALLOC_END ?: 96UL << 20;
569 	vmax = 1UL << 31;		/* 2-level kernel page table */
570 	/* vmalloc area is at the end of the kernel address space. */
571 	VMALLOC_END = vmax;
572 #endif
573 	VMALLOC_START = vmax - vmalloc_size;
574 
575 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
576 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
577 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
578 	tmp = SECTION_ALIGN_UP(tmp);
579 	tmp = VMALLOC_START - tmp * sizeof(struct page);
580 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
581 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
582 	vmemmap = (struct page *) tmp;
583 
584 	/* Take care that memory_end is set and <= vmemmap */
585 	memory_end = min(memory_end ?: real_memory_size, tmp);
586 
587 	/* Fixup memory chunk array to fit into 0..memory_end */
588 	for (i = 0; i < MEMORY_CHUNKS; i++) {
589 		struct mem_chunk *chunk = &memory_chunk[i];
590 
591 		if (chunk->addr >= memory_end) {
592 			memset(chunk, 0, sizeof(*chunk));
593 			continue;
594 		}
595 		if (chunk->addr + chunk->size > memory_end)
596 			chunk->size = memory_end - chunk->addr;
597 	}
598 }
599 
600 static void __init setup_vmcoreinfo(void)
601 {
602 	mem_assign_absolute(S390_lowcore.vmcore_info, paddr_vmcoreinfo_note());
603 }
604 
605 #ifdef CONFIG_CRASH_DUMP
606 
607 /*
608  * Find suitable location for crashkernel memory
609  */
610 static unsigned long __init find_crash_base(unsigned long crash_size,
611 					    char **msg)
612 {
613 	unsigned long crash_base;
614 	struct mem_chunk *chunk;
615 	int i;
616 
617 	if (memory_chunk[0].size < crash_size) {
618 		*msg = "first memory chunk must be at least crashkernel size";
619 		return 0;
620 	}
621 	if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
622 		return OLDMEM_BASE;
623 
624 	for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
625 		chunk = &memory_chunk[i];
626 		if (chunk->size == 0)
627 			continue;
628 		if (chunk->type != CHUNK_READ_WRITE)
629 			continue;
630 		if (chunk->size < crash_size)
631 			continue;
632 		crash_base = (chunk->addr + chunk->size) - crash_size;
633 		if (crash_base < crash_size)
634 			continue;
635 		if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
636 			continue;
637 		if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
638 			continue;
639 		return crash_base;
640 	}
641 	*msg = "no suitable area found";
642 	return 0;
643 }
644 
645 /*
646  * Check if crash_base and crash_size is valid
647  */
648 static int __init verify_crash_base(unsigned long crash_base,
649 				    unsigned long crash_size,
650 				    char **msg)
651 {
652 	struct mem_chunk *chunk;
653 	int i;
654 
655 	/*
656 	 * Because we do the swap to zero, we must have at least 'crash_size'
657 	 * bytes free space before crash_base
658 	 */
659 	if (crash_size > crash_base) {
660 		*msg = "crashkernel offset must be greater than size";
661 		return -EINVAL;
662 	}
663 
664 	/* First memory chunk must be at least crash_size */
665 	if (memory_chunk[0].size < crash_size) {
666 		*msg = "first memory chunk must be at least crashkernel size";
667 		return -EINVAL;
668 	}
669 	/* Check if we fit into the respective memory chunk */
670 	for (i = 0; i < MEMORY_CHUNKS; i++) {
671 		chunk = &memory_chunk[i];
672 		if (chunk->size == 0)
673 			continue;
674 		if (crash_base < chunk->addr)
675 			continue;
676 		if (crash_base >= chunk->addr + chunk->size)
677 			continue;
678 		/* we have found the memory chunk */
679 		if (crash_base + crash_size > chunk->addr + chunk->size) {
680 			*msg = "selected memory chunk is too small for "
681 				"crashkernel memory";
682 			return -EINVAL;
683 		}
684 		return 0;
685 	}
686 	*msg = "invalid memory range specified";
687 	return -EINVAL;
688 }
689 
690 /*
691  * Reserve kdump memory by creating a memory hole in the mem_chunk array
692  */
693 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
694 					 int type)
695 {
696 	create_mem_hole(memory_chunk, addr, size, type);
697 }
698 
699 /*
700  * When kdump is enabled, we have to ensure that no memory from
701  * the area [0 - crashkernel memory size] and
702  * [crashk_res.start - crashk_res.end] is set offline.
703  */
704 static int kdump_mem_notifier(struct notifier_block *nb,
705 			      unsigned long action, void *data)
706 {
707 	struct memory_notify *arg = data;
708 
709 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
710 		return NOTIFY_BAD;
711 	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
712 		return NOTIFY_OK;
713 	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
714 		return NOTIFY_OK;
715 	return NOTIFY_BAD;
716 }
717 
718 static struct notifier_block kdump_mem_nb = {
719 	.notifier_call = kdump_mem_notifier,
720 };
721 
722 #endif
723 
724 /*
725  * Make sure that oldmem, where the dump is stored, is protected
726  */
727 static void reserve_oldmem(void)
728 {
729 #ifdef CONFIG_CRASH_DUMP
730 	if (!OLDMEM_BASE)
731 		return;
732 
733 	reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
734 	reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
735 			      CHUNK_OLDMEM);
736 	if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
737 		saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
738 	else
739 		saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
740 #endif
741 }
742 
743 /*
744  * Reserve memory for kdump kernel to be loaded with kexec
745  */
746 static void __init reserve_crashkernel(void)
747 {
748 #ifdef CONFIG_CRASH_DUMP
749 	unsigned long long crash_base, crash_size;
750 	char *msg = NULL;
751 	int rc;
752 
753 	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
754 			       &crash_base);
755 	if (rc || crash_size == 0)
756 		return;
757 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
758 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
759 	if (register_memory_notifier(&kdump_mem_nb))
760 		return;
761 	if (!crash_base)
762 		crash_base = find_crash_base(crash_size, &msg);
763 	if (!crash_base) {
764 		pr_info("crashkernel reservation failed: %s\n", msg);
765 		unregister_memory_notifier(&kdump_mem_nb);
766 		return;
767 	}
768 	if (verify_crash_base(crash_base, crash_size, &msg)) {
769 		pr_info("crashkernel reservation failed: %s\n", msg);
770 		unregister_memory_notifier(&kdump_mem_nb);
771 		return;
772 	}
773 	if (!OLDMEM_BASE && MACHINE_IS_VM)
774 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
775 	crashk_res.start = crash_base;
776 	crashk_res.end = crash_base + crash_size - 1;
777 	insert_resource(&iomem_resource, &crashk_res);
778 	reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
779 	pr_info("Reserving %lluMB of memory at %lluMB "
780 		"for crashkernel (System RAM: %luMB)\n",
781 		crash_size >> 20, crash_base >> 20, memory_end >> 20);
782 	os_info_crashkernel_add(crash_base, crash_size);
783 #endif
784 }
785 
786 static void __init setup_memory(void)
787 {
788         unsigned long bootmap_size;
789 	unsigned long start_pfn, end_pfn;
790 	int i;
791 
792 	/*
793 	 * partially used pages are not usable - thus
794 	 * we are rounding upwards:
795 	 */
796 	start_pfn = PFN_UP(__pa(&_end));
797 	end_pfn = max_pfn = PFN_DOWN(memory_end);
798 
799 #ifdef CONFIG_BLK_DEV_INITRD
800 	/*
801 	 * Move the initrd in case the bitmap of the bootmem allocater
802 	 * would overwrite it.
803 	 */
804 
805 	if (INITRD_START && INITRD_SIZE) {
806 		unsigned long bmap_size;
807 		unsigned long start;
808 
809 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
810 		bmap_size = PFN_PHYS(bmap_size);
811 
812 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
813 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
814 
815 #ifdef CONFIG_CRASH_DUMP
816 			if (OLDMEM_BASE) {
817 				/* Move initrd behind kdump oldmem */
818 				if (start + INITRD_SIZE > OLDMEM_BASE &&
819 				    start < OLDMEM_BASE + OLDMEM_SIZE)
820 					start = OLDMEM_BASE + OLDMEM_SIZE;
821 			}
822 #endif
823 			if (start + INITRD_SIZE > memory_end) {
824 				pr_err("initrd extends beyond end of "
825 				       "memory (0x%08lx > 0x%08lx) "
826 				       "disabling initrd\n",
827 				       start + INITRD_SIZE, memory_end);
828 				INITRD_START = INITRD_SIZE = 0;
829 			} else {
830 				pr_info("Moving initrd (0x%08lx -> "
831 					"0x%08lx, size: %ld)\n",
832 					INITRD_START, start, INITRD_SIZE);
833 				memmove((void *) start, (void *) INITRD_START,
834 					INITRD_SIZE);
835 				INITRD_START = start;
836 			}
837 		}
838 	}
839 #endif
840 
841 	/*
842 	 * Initialize the boot-time allocator
843 	 */
844 	bootmap_size = init_bootmem(start_pfn, end_pfn);
845 
846 	/*
847 	 * Register RAM areas with the bootmem allocator.
848 	 */
849 
850 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
851 		unsigned long start_chunk, end_chunk, pfn;
852 
853 		if (memory_chunk[i].type != CHUNK_READ_WRITE &&
854 		    memory_chunk[i].type != CHUNK_CRASHK)
855 			continue;
856 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
857 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
858 		end_chunk = min(end_chunk, end_pfn);
859 		if (start_chunk >= end_chunk)
860 			continue;
861 		memblock_add_node(PFN_PHYS(start_chunk),
862 				  PFN_PHYS(end_chunk - start_chunk), 0);
863 		pfn = max(start_chunk, start_pfn);
864 		storage_key_init_range(PFN_PHYS(pfn), PFN_PHYS(end_chunk));
865 	}
866 
867 	psw_set_key(PAGE_DEFAULT_KEY);
868 
869 	free_bootmem_with_active_regions(0, max_pfn);
870 
871 	/*
872 	 * Reserve memory used for lowcore/command line/kernel image.
873 	 */
874 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
875 	reserve_bootmem((unsigned long)_stext,
876 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
877 			BOOTMEM_DEFAULT);
878 	/*
879 	 * Reserve the bootmem bitmap itself as well. We do this in two
880 	 * steps (first step was init_bootmem()) because this catches
881 	 * the (very unlikely) case of us accidentally initializing the
882 	 * bootmem allocator with an invalid RAM area.
883 	 */
884 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
885 			BOOTMEM_DEFAULT);
886 
887 #ifdef CONFIG_CRASH_DUMP
888 	if (crashk_res.start)
889 		reserve_bootmem(crashk_res.start,
890 				crashk_res.end - crashk_res.start + 1,
891 				BOOTMEM_DEFAULT);
892 	if (is_kdump_kernel())
893 		reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
894 				PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
895 #endif
896 #ifdef CONFIG_BLK_DEV_INITRD
897 	if (INITRD_START && INITRD_SIZE) {
898 		if (INITRD_START + INITRD_SIZE <= memory_end) {
899 			reserve_bootmem(INITRD_START, INITRD_SIZE,
900 					BOOTMEM_DEFAULT);
901 			initrd_start = INITRD_START;
902 			initrd_end = initrd_start + INITRD_SIZE;
903 		} else {
904 			pr_err("initrd extends beyond end of "
905 			       "memory (0x%08lx > 0x%08lx) "
906 			       "disabling initrd\n",
907 			       initrd_start + INITRD_SIZE, memory_end);
908 			initrd_start = initrd_end = 0;
909 		}
910 	}
911 #endif
912 }
913 
914 /*
915  * Setup hardware capabilities.
916  */
917 static void __init setup_hwcaps(void)
918 {
919 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
920 	struct cpuid cpu_id;
921 	int i;
922 
923 	/*
924 	 * The store facility list bits numbers as found in the principles
925 	 * of operation are numbered with bit 1UL<<31 as number 0 to
926 	 * bit 1UL<<0 as number 31.
927 	 *   Bit 0: instructions named N3, "backported" to esa-mode
928 	 *   Bit 2: z/Architecture mode is active
929 	 *   Bit 7: the store-facility-list-extended facility is installed
930 	 *   Bit 17: the message-security assist is installed
931 	 *   Bit 19: the long-displacement facility is installed
932 	 *   Bit 21: the extended-immediate facility is installed
933 	 *   Bit 22: extended-translation facility 3 is installed
934 	 *   Bit 30: extended-translation facility 3 enhancement facility
935 	 * These get translated to:
936 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
937 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
938 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
939 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
940 	 */
941 	for (i = 0; i < 6; i++)
942 		if (test_facility(stfl_bits[i]))
943 			elf_hwcap |= 1UL << i;
944 
945 	if (test_facility(22) && test_facility(30))
946 		elf_hwcap |= HWCAP_S390_ETF3EH;
947 
948 	/*
949 	 * Check for additional facilities with store-facility-list-extended.
950 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
951 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
952 	 * as stored by stfl, bits 32-xxx contain additional facilities.
953 	 * How many facility words are stored depends on the number of
954 	 * doublewords passed to the instruction. The additional facilities
955 	 * are:
956 	 *   Bit 42: decimal floating point facility is installed
957 	 *   Bit 44: perform floating point operation facility is installed
958 	 * translated to:
959 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
960 	 */
961 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
962 		elf_hwcap |= HWCAP_S390_DFP;
963 
964 	/*
965 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
966 	 */
967 	if (MACHINE_HAS_HPAGE)
968 		elf_hwcap |= HWCAP_S390_HPAGE;
969 
970 #if defined(CONFIG_64BIT)
971 	/*
972 	 * 64-bit register support for 31-bit processes
973 	 * HWCAP_S390_HIGH_GPRS is bit 9.
974 	 */
975 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
976 
977 	/*
978 	 * Transactional execution support HWCAP_S390_TE is bit 10.
979 	 */
980 	if (test_facility(50) && test_facility(73))
981 		elf_hwcap |= HWCAP_S390_TE;
982 #endif
983 
984 	get_cpu_id(&cpu_id);
985 	switch (cpu_id.machine) {
986 	case 0x9672:
987 #if !defined(CONFIG_64BIT)
988 	default:	/* Use "g5" as default for 31 bit kernels. */
989 #endif
990 		strcpy(elf_platform, "g5");
991 		break;
992 	case 0x2064:
993 	case 0x2066:
994 #if defined(CONFIG_64BIT)
995 	default:	/* Use "z900" as default for 64 bit kernels. */
996 #endif
997 		strcpy(elf_platform, "z900");
998 		break;
999 	case 0x2084:
1000 	case 0x2086:
1001 		strcpy(elf_platform, "z990");
1002 		break;
1003 	case 0x2094:
1004 	case 0x2096:
1005 		strcpy(elf_platform, "z9-109");
1006 		break;
1007 	case 0x2097:
1008 	case 0x2098:
1009 		strcpy(elf_platform, "z10");
1010 		break;
1011 	case 0x2817:
1012 	case 0x2818:
1013 		strcpy(elf_platform, "z196");
1014 		break;
1015 	case 0x2827:
1016 		strcpy(elf_platform, "zEC12");
1017 		break;
1018 	}
1019 }
1020 
1021 /*
1022  * Setup function called from init/main.c just after the banner
1023  * was printed.
1024  */
1025 
1026 void __init setup_arch(char **cmdline_p)
1027 {
1028         /*
1029          * print what head.S has found out about the machine
1030          */
1031 #ifndef CONFIG_64BIT
1032 	if (MACHINE_IS_VM)
1033 		pr_info("Linux is running as a z/VM "
1034 			"guest operating system in 31-bit mode\n");
1035 	else if (MACHINE_IS_LPAR)
1036 		pr_info("Linux is running natively in 31-bit mode\n");
1037 	if (MACHINE_HAS_IEEE)
1038 		pr_info("The hardware system has IEEE compatible "
1039 			"floating point units\n");
1040 	else
1041 		pr_info("The hardware system has no IEEE compatible "
1042 			"floating point units\n");
1043 #else /* CONFIG_64BIT */
1044 	if (MACHINE_IS_VM)
1045 		pr_info("Linux is running as a z/VM "
1046 			"guest operating system in 64-bit mode\n");
1047 	else if (MACHINE_IS_KVM)
1048 		pr_info("Linux is running under KVM in 64-bit mode\n");
1049 	else if (MACHINE_IS_LPAR)
1050 		pr_info("Linux is running natively in 64-bit mode\n");
1051 #endif /* CONFIG_64BIT */
1052 
1053 	/* Have one command line that is parsed and saved in /proc/cmdline */
1054 	/* boot_command_line has been already set up in early.c */
1055 	*cmdline_p = boot_command_line;
1056 
1057         ROOT_DEV = Root_RAM0;
1058 
1059 	init_mm.start_code = PAGE_OFFSET;
1060 	init_mm.end_code = (unsigned long) &_etext;
1061 	init_mm.end_data = (unsigned long) &_edata;
1062 	init_mm.brk = (unsigned long) &_end;
1063 
1064 	if (MACHINE_HAS_MVCOS)
1065 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1066 	else
1067 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1068 
1069 	parse_early_param();
1070 
1071 	os_info_init();
1072 	setup_ipl();
1073 	setup_memory_end();
1074 	setup_addressing_mode();
1075 	reserve_oldmem();
1076 	reserve_crashkernel();
1077 	setup_memory();
1078 	setup_resources();
1079 	setup_vmcoreinfo();
1080 	setup_lowcore();
1081 
1082         cpu_init();
1083 	s390_init_cpu_topology();
1084 
1085 	/*
1086 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1087 	 */
1088 	setup_hwcaps();
1089 
1090 	/*
1091 	 * Create kernel page tables and switch to virtual addressing.
1092 	 */
1093         paging_init();
1094 
1095         /* Setup default console */
1096 	conmode_default();
1097 	set_preferred_console();
1098 
1099 	/* Setup zfcpdump support */
1100 	setup_zfcpdump(console_devno);
1101 }
1102