xref: /openbmc/linux/arch/s390/kernel/setup.c (revision 80ecbd24)
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(void)
230 {
231 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
232 		return;
233 	if (OLDMEM_BASE)
234 		return;
235 	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
236 	console_loglevel = 2;
237 }
238 #else
239 static inline void setup_zfcpdump(void) {}
240 #endif /* CONFIG_ZFCPDUMP */
241 
242  /*
243  * Reboot, halt and power_off stubs. They just call _machine_restart,
244  * _machine_halt or _machine_power_off.
245  */
246 
247 void machine_restart(char *command)
248 {
249 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
250 		/*
251 		 * Only unblank the console if we are called in enabled
252 		 * context or a bust_spinlocks cleared the way for us.
253 		 */
254 		console_unblank();
255 	_machine_restart(command);
256 }
257 
258 void machine_halt(void)
259 {
260 	if (!in_interrupt() || oops_in_progress)
261 		/*
262 		 * Only unblank the console if we are called in enabled
263 		 * context or a bust_spinlocks cleared the way for us.
264 		 */
265 		console_unblank();
266 	_machine_halt();
267 }
268 
269 void machine_power_off(void)
270 {
271 	if (!in_interrupt() || oops_in_progress)
272 		/*
273 		 * Only unblank the console if we are called in enabled
274 		 * context or a bust_spinlocks cleared the way for us.
275 		 */
276 		console_unblank();
277 	_machine_power_off();
278 }
279 
280 /*
281  * Dummy power off function.
282  */
283 void (*pm_power_off)(void) = machine_power_off;
284 EXPORT_SYMBOL_GPL(pm_power_off);
285 
286 static int __init early_parse_mem(char *p)
287 {
288 	memory_end = memparse(p, &p);
289 	memory_end_set = 1;
290 	return 0;
291 }
292 early_param("mem", early_parse_mem);
293 
294 static int __init parse_vmalloc(char *arg)
295 {
296 	if (!arg)
297 		return -EINVAL;
298 	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
299 	return 0;
300 }
301 early_param("vmalloc", parse_vmalloc);
302 
303 unsigned int s390_user_mode = PRIMARY_SPACE_MODE;
304 EXPORT_SYMBOL_GPL(s390_user_mode);
305 
306 static void __init set_user_mode_primary(void)
307 {
308 	psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
309 	psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
310 #ifdef CONFIG_COMPAT
311 	psw32_user_bits =
312 		(psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
313 #endif
314 	uaccess = MACHINE_HAS_MVCOS ? uaccess_mvcos_switch : uaccess_pt;
315 }
316 
317 static int __init early_parse_user_mode(char *p)
318 {
319 	if (p && strcmp(p, "primary") == 0)
320 		s390_user_mode = PRIMARY_SPACE_MODE;
321 	else if (!p || strcmp(p, "home") == 0)
322 		s390_user_mode = HOME_SPACE_MODE;
323 	else
324 		return 1;
325 	return 0;
326 }
327 early_param("user_mode", early_parse_user_mode);
328 
329 static void __init setup_addressing_mode(void)
330 {
331 	if (s390_user_mode != PRIMARY_SPACE_MODE)
332 		return;
333 	set_user_mode_primary();
334 	if (MACHINE_HAS_MVCOS)
335 		pr_info("Address spaces switched, mvcos available\n");
336 	else
337 		pr_info("Address spaces switched, mvcos not available\n");
338 }
339 
340 void *restart_stack __attribute__((__section__(".data")));
341 
342 static void __init setup_lowcore(void)
343 {
344 	struct _lowcore *lc;
345 
346 	/*
347 	 * Setup lowcore for boot cpu
348 	 */
349 	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
350 	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
351 	lc->restart_psw.mask = psw_kernel_bits;
352 	lc->restart_psw.addr =
353 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
354 	lc->external_new_psw.mask = psw_kernel_bits |
355 		PSW_MASK_DAT | PSW_MASK_MCHECK;
356 	lc->external_new_psw.addr =
357 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
358 	lc->svc_new_psw.mask = psw_kernel_bits |
359 		PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
360 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
361 	lc->program_new_psw.mask = psw_kernel_bits |
362 		PSW_MASK_DAT | PSW_MASK_MCHECK;
363 	lc->program_new_psw.addr =
364 		PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
365 	lc->mcck_new_psw.mask = psw_kernel_bits;
366 	lc->mcck_new_psw.addr =
367 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
368 	lc->io_new_psw.mask = psw_kernel_bits |
369 		PSW_MASK_DAT | PSW_MASK_MCHECK;
370 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
371 	lc->clock_comparator = -1ULL;
372 	lc->kernel_stack = ((unsigned long) &init_thread_union)
373 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
374 	lc->async_stack = (unsigned long)
375 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0)
376 		+ ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
377 	lc->panic_stack = (unsigned long)
378 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0)
379 		+ PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
380 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
381 	lc->thread_info = (unsigned long) &init_thread_union;
382 	lc->machine_flags = S390_lowcore.machine_flags;
383 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
384 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
385 	       MAX_FACILITY_BIT/8);
386 #ifndef CONFIG_64BIT
387 	if (MACHINE_HAS_IEEE) {
388 		lc->extended_save_area_addr = (__u32)
389 			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
390 		/* enable extended save area */
391 		__ctl_set_bit(14, 29);
392 	}
393 #else
394 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
395 #endif
396 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
397 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
398 	lc->exit_timer = S390_lowcore.exit_timer;
399 	lc->user_timer = S390_lowcore.user_timer;
400 	lc->system_timer = S390_lowcore.system_timer;
401 	lc->steal_timer = S390_lowcore.steal_timer;
402 	lc->last_update_timer = S390_lowcore.last_update_timer;
403 	lc->last_update_clock = S390_lowcore.last_update_clock;
404 	lc->ftrace_func = S390_lowcore.ftrace_func;
405 
406 	restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
407 	restart_stack += ASYNC_SIZE;
408 
409 	/*
410 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
411 	 * restart data to the absolute zero lowcore. This is necesary if
412 	 * PSW restart is done on an offline CPU that has lowcore zero.
413 	 */
414 	lc->restart_stack = (unsigned long) restart_stack;
415 	lc->restart_fn = (unsigned long) do_restart;
416 	lc->restart_data = 0;
417 	lc->restart_source = -1UL;
418 
419 	/* Setup absolute zero lowcore */
420 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
421 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
422 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
423 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
424 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
425 
426 	set_prefix((u32)(unsigned long) lc);
427 	lowcore_ptr[0] = lc;
428 }
429 
430 static struct resource code_resource = {
431 	.name  = "Kernel code",
432 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
433 };
434 
435 static struct resource data_resource = {
436 	.name = "Kernel data",
437 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
438 };
439 
440 static struct resource bss_resource = {
441 	.name = "Kernel bss",
442 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
443 };
444 
445 static struct resource __initdata *standard_resources[] = {
446 	&code_resource,
447 	&data_resource,
448 	&bss_resource,
449 };
450 
451 static void __init setup_resources(void)
452 {
453 	struct resource *res, *std_res, *sub_res;
454 	int i, j;
455 
456 	code_resource.start = (unsigned long) &_text;
457 	code_resource.end = (unsigned long) &_etext - 1;
458 	data_resource.start = (unsigned long) &_etext;
459 	data_resource.end = (unsigned long) &_edata - 1;
460 	bss_resource.start = (unsigned long) &__bss_start;
461 	bss_resource.end = (unsigned long) &__bss_stop - 1;
462 
463 	for (i = 0; i < MEMORY_CHUNKS; i++) {
464 		if (!memory_chunk[i].size)
465 			continue;
466 		res = alloc_bootmem_low(sizeof(*res));
467 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
468 		switch (memory_chunk[i].type) {
469 		case CHUNK_READ_WRITE:
470 			res->name = "System RAM";
471 			break;
472 		case CHUNK_READ_ONLY:
473 			res->name = "System ROM";
474 			res->flags |= IORESOURCE_READONLY;
475 			break;
476 		default:
477 			res->name = "reserved";
478 		}
479 		res->start = memory_chunk[i].addr;
480 		res->end = res->start + memory_chunk[i].size - 1;
481 		request_resource(&iomem_resource, res);
482 
483 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
484 			std_res = standard_resources[j];
485 			if (std_res->start < res->start ||
486 			    std_res->start > res->end)
487 				continue;
488 			if (std_res->end > res->end) {
489 				sub_res = alloc_bootmem_low(sizeof(*sub_res));
490 				*sub_res = *std_res;
491 				sub_res->end = res->end;
492 				std_res->start = res->end + 1;
493 				request_resource(res, sub_res);
494 			} else {
495 				request_resource(res, std_res);
496 			}
497 		}
498 	}
499 }
500 
501 static void __init setup_memory_end(void)
502 {
503 	unsigned long vmax, vmalloc_size, tmp;
504 	unsigned long real_memory_size = 0;
505 	int i;
506 
507 
508 #ifdef CONFIG_ZFCPDUMP
509 	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
510 		memory_end = ZFCPDUMP_HSA_SIZE;
511 		memory_end_set = 1;
512 	}
513 #endif
514 	memory_end &= PAGE_MASK;
515 
516 	/*
517 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
518 	 * extra checks that HOLES_IN_ZONE would require.
519 	 */
520 	for (i = 0; i < MEMORY_CHUNKS; i++) {
521 		unsigned long start, end;
522 		struct mem_chunk *chunk;
523 		unsigned long align;
524 
525 		chunk = &memory_chunk[i];
526 		if (!chunk->size)
527 			continue;
528 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
529 		start = (chunk->addr + align - 1) & ~(align - 1);
530 		end = (chunk->addr + chunk->size) & ~(align - 1);
531 		if (start >= end)
532 			memset(chunk, 0, sizeof(*chunk));
533 		else {
534 			chunk->addr = start;
535 			chunk->size = end - start;
536 		}
537 		real_memory_size = max(real_memory_size,
538 				       chunk->addr + chunk->size);
539 	}
540 
541 	/* Choose kernel address space layout: 2, 3, or 4 levels. */
542 #ifdef CONFIG_64BIT
543 	vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
544 	tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
545 	tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
546 	if (tmp <= (1UL << 42))
547 		vmax = 1UL << 42;	/* 3-level kernel page table */
548 	else
549 		vmax = 1UL << 53;	/* 4-level kernel page table */
550 	/* module area is at the end of the kernel address space. */
551 	MODULES_END = vmax;
552 	MODULES_VADDR = MODULES_END - MODULES_LEN;
553 	VMALLOC_END = MODULES_VADDR;
554 #else
555 	vmalloc_size = VMALLOC_END ?: 96UL << 20;
556 	vmax = 1UL << 31;		/* 2-level kernel page table */
557 	/* vmalloc area is at the end of the kernel address space. */
558 	VMALLOC_END = vmax;
559 #endif
560 	VMALLOC_START = vmax - vmalloc_size;
561 
562 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
563 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
564 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
565 	tmp = SECTION_ALIGN_UP(tmp);
566 	tmp = VMALLOC_START - tmp * sizeof(struct page);
567 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
568 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
569 	vmemmap = (struct page *) tmp;
570 
571 	/* Take care that memory_end is set and <= vmemmap */
572 	memory_end = min(memory_end ?: real_memory_size, tmp);
573 
574 	/* Fixup memory chunk array to fit into 0..memory_end */
575 	for (i = 0; i < MEMORY_CHUNKS; i++) {
576 		struct mem_chunk *chunk = &memory_chunk[i];
577 
578 		if (!chunk->size)
579 			continue;
580 		if (chunk->addr >= memory_end) {
581 			memset(chunk, 0, sizeof(*chunk));
582 			continue;
583 		}
584 		if (chunk->addr + chunk->size > memory_end)
585 			chunk->size = memory_end - chunk->addr;
586 	}
587 }
588 
589 static void __init setup_vmcoreinfo(void)
590 {
591 	mem_assign_absolute(S390_lowcore.vmcore_info, paddr_vmcoreinfo_note());
592 }
593 
594 #ifdef CONFIG_CRASH_DUMP
595 
596 /*
597  * Find suitable location for crashkernel memory
598  */
599 static unsigned long __init find_crash_base(unsigned long crash_size,
600 					    char **msg)
601 {
602 	unsigned long crash_base;
603 	struct mem_chunk *chunk;
604 	int i;
605 
606 	if (memory_chunk[0].size < crash_size) {
607 		*msg = "first memory chunk must be at least crashkernel size";
608 		return 0;
609 	}
610 	if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
611 		return OLDMEM_BASE;
612 
613 	for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
614 		chunk = &memory_chunk[i];
615 		if (chunk->size == 0)
616 			continue;
617 		if (chunk->type != CHUNK_READ_WRITE)
618 			continue;
619 		if (chunk->size < crash_size)
620 			continue;
621 		crash_base = (chunk->addr + chunk->size) - crash_size;
622 		if (crash_base < crash_size)
623 			continue;
624 		if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
625 			continue;
626 		if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
627 			continue;
628 		return crash_base;
629 	}
630 	*msg = "no suitable area found";
631 	return 0;
632 }
633 
634 /*
635  * Check if crash_base and crash_size is valid
636  */
637 static int __init verify_crash_base(unsigned long crash_base,
638 				    unsigned long crash_size,
639 				    char **msg)
640 {
641 	struct mem_chunk *chunk;
642 	int i;
643 
644 	/*
645 	 * Because we do the swap to zero, we must have at least 'crash_size'
646 	 * bytes free space before crash_base
647 	 */
648 	if (crash_size > crash_base) {
649 		*msg = "crashkernel offset must be greater than size";
650 		return -EINVAL;
651 	}
652 
653 	/* First memory chunk must be at least crash_size */
654 	if (memory_chunk[0].size < crash_size) {
655 		*msg = "first memory chunk must be at least crashkernel size";
656 		return -EINVAL;
657 	}
658 	/* Check if we fit into the respective memory chunk */
659 	for (i = 0; i < MEMORY_CHUNKS; i++) {
660 		chunk = &memory_chunk[i];
661 		if (chunk->size == 0)
662 			continue;
663 		if (crash_base < chunk->addr)
664 			continue;
665 		if (crash_base >= chunk->addr + chunk->size)
666 			continue;
667 		/* we have found the memory chunk */
668 		if (crash_base + crash_size > chunk->addr + chunk->size) {
669 			*msg = "selected memory chunk is too small for "
670 				"crashkernel memory";
671 			return -EINVAL;
672 		}
673 		return 0;
674 	}
675 	*msg = "invalid memory range specified";
676 	return -EINVAL;
677 }
678 
679 /*
680  * When kdump is enabled, we have to ensure that no memory from
681  * the area [0 - crashkernel memory size] and
682  * [crashk_res.start - crashk_res.end] is set offline.
683  */
684 static int kdump_mem_notifier(struct notifier_block *nb,
685 			      unsigned long action, void *data)
686 {
687 	struct memory_notify *arg = data;
688 
689 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
690 		return NOTIFY_BAD;
691 	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
692 		return NOTIFY_OK;
693 	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
694 		return NOTIFY_OK;
695 	return NOTIFY_BAD;
696 }
697 
698 static struct notifier_block kdump_mem_nb = {
699 	.notifier_call = kdump_mem_notifier,
700 };
701 
702 #endif
703 
704 /*
705  * Make sure that oldmem, where the dump is stored, is protected
706  */
707 static void reserve_oldmem(void)
708 {
709 #ifdef CONFIG_CRASH_DUMP
710 	unsigned long real_size = 0;
711 	int i;
712 
713 	if (!OLDMEM_BASE)
714 		return;
715 	for (i = 0; i < MEMORY_CHUNKS; i++) {
716 		struct mem_chunk *chunk = &memory_chunk[i];
717 
718 		real_size = max(real_size, chunk->addr + chunk->size);
719 	}
720 	create_mem_hole(memory_chunk, OLDMEM_BASE, OLDMEM_SIZE);
721 	create_mem_hole(memory_chunk, OLDMEM_SIZE, real_size - OLDMEM_SIZE);
722 #endif
723 }
724 
725 /*
726  * Reserve memory for kdump kernel to be loaded with kexec
727  */
728 static void __init reserve_crashkernel(void)
729 {
730 #ifdef CONFIG_CRASH_DUMP
731 	unsigned long long crash_base, crash_size;
732 	char *msg = NULL;
733 	int rc;
734 
735 	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
736 			       &crash_base);
737 	if (rc || crash_size == 0)
738 		return;
739 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
740 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
741 	if (register_memory_notifier(&kdump_mem_nb))
742 		return;
743 	if (!crash_base)
744 		crash_base = find_crash_base(crash_size, &msg);
745 	if (!crash_base) {
746 		pr_info("crashkernel reservation failed: %s\n", msg);
747 		unregister_memory_notifier(&kdump_mem_nb);
748 		return;
749 	}
750 	if (verify_crash_base(crash_base, crash_size, &msg)) {
751 		pr_info("crashkernel reservation failed: %s\n", msg);
752 		unregister_memory_notifier(&kdump_mem_nb);
753 		return;
754 	}
755 	if (!OLDMEM_BASE && MACHINE_IS_VM)
756 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
757 	crashk_res.start = crash_base;
758 	crashk_res.end = crash_base + crash_size - 1;
759 	insert_resource(&iomem_resource, &crashk_res);
760 	create_mem_hole(memory_chunk, crash_base, crash_size);
761 	pr_info("Reserving %lluMB of memory at %lluMB "
762 		"for crashkernel (System RAM: %luMB)\n",
763 		crash_size >> 20, crash_base >> 20, memory_end >> 20);
764 	os_info_crashkernel_add(crash_base, crash_size);
765 #endif
766 }
767 
768 static void __init setup_memory(void)
769 {
770         unsigned long bootmap_size;
771 	unsigned long start_pfn, end_pfn;
772 	int i;
773 
774 	/*
775 	 * partially used pages are not usable - thus
776 	 * we are rounding upwards:
777 	 */
778 	start_pfn = PFN_UP(__pa(&_end));
779 	end_pfn = max_pfn = PFN_DOWN(memory_end);
780 
781 #ifdef CONFIG_BLK_DEV_INITRD
782 	/*
783 	 * Move the initrd in case the bitmap of the bootmem allocater
784 	 * would overwrite it.
785 	 */
786 
787 	if (INITRD_START && INITRD_SIZE) {
788 		unsigned long bmap_size;
789 		unsigned long start;
790 
791 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
792 		bmap_size = PFN_PHYS(bmap_size);
793 
794 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
795 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
796 
797 #ifdef CONFIG_CRASH_DUMP
798 			if (OLDMEM_BASE) {
799 				/* Move initrd behind kdump oldmem */
800 				if (start + INITRD_SIZE > OLDMEM_BASE &&
801 				    start < OLDMEM_BASE + OLDMEM_SIZE)
802 					start = OLDMEM_BASE + OLDMEM_SIZE;
803 			}
804 #endif
805 			if (start + INITRD_SIZE > memory_end) {
806 				pr_err("initrd extends beyond end of "
807 				       "memory (0x%08lx > 0x%08lx) "
808 				       "disabling initrd\n",
809 				       start + INITRD_SIZE, memory_end);
810 				INITRD_START = INITRD_SIZE = 0;
811 			} else {
812 				pr_info("Moving initrd (0x%08lx -> "
813 					"0x%08lx, size: %ld)\n",
814 					INITRD_START, start, INITRD_SIZE);
815 				memmove((void *) start, (void *) INITRD_START,
816 					INITRD_SIZE);
817 				INITRD_START = start;
818 			}
819 		}
820 	}
821 #endif
822 
823 	/*
824 	 * Initialize the boot-time allocator
825 	 */
826 	bootmap_size = init_bootmem(start_pfn, end_pfn);
827 
828 	/*
829 	 * Register RAM areas with the bootmem allocator.
830 	 */
831 
832 	for (i = 0; i < MEMORY_CHUNKS; i++) {
833 		unsigned long start_chunk, end_chunk, pfn;
834 
835 		if (!memory_chunk[i].size)
836 			continue;
837 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
838 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
839 		end_chunk = min(end_chunk, end_pfn);
840 		if (start_chunk >= end_chunk)
841 			continue;
842 		memblock_add_node(PFN_PHYS(start_chunk),
843 				  PFN_PHYS(end_chunk - start_chunk), 0);
844 		pfn = max(start_chunk, start_pfn);
845 		storage_key_init_range(PFN_PHYS(pfn), PFN_PHYS(end_chunk));
846 	}
847 
848 	psw_set_key(PAGE_DEFAULT_KEY);
849 
850 	free_bootmem_with_active_regions(0, max_pfn);
851 
852 	/*
853 	 * Reserve memory used for lowcore/command line/kernel image.
854 	 */
855 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
856 	reserve_bootmem((unsigned long)_stext,
857 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
858 			BOOTMEM_DEFAULT);
859 	/*
860 	 * Reserve the bootmem bitmap itself as well. We do this in two
861 	 * steps (first step was init_bootmem()) because this catches
862 	 * the (very unlikely) case of us accidentally initializing the
863 	 * bootmem allocator with an invalid RAM area.
864 	 */
865 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
866 			BOOTMEM_DEFAULT);
867 
868 #ifdef CONFIG_CRASH_DUMP
869 	if (crashk_res.start)
870 		reserve_bootmem(crashk_res.start,
871 				crashk_res.end - crashk_res.start + 1,
872 				BOOTMEM_DEFAULT);
873 	if (is_kdump_kernel())
874 		reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
875 				PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
876 #endif
877 #ifdef CONFIG_BLK_DEV_INITRD
878 	if (INITRD_START && INITRD_SIZE) {
879 		if (INITRD_START + INITRD_SIZE <= memory_end) {
880 			reserve_bootmem(INITRD_START, INITRD_SIZE,
881 					BOOTMEM_DEFAULT);
882 			initrd_start = INITRD_START;
883 			initrd_end = initrd_start + INITRD_SIZE;
884 		} else {
885 			pr_err("initrd extends beyond end of "
886 			       "memory (0x%08lx > 0x%08lx) "
887 			       "disabling initrd\n",
888 			       initrd_start + INITRD_SIZE, memory_end);
889 			initrd_start = initrd_end = 0;
890 		}
891 	}
892 #endif
893 }
894 
895 /*
896  * Setup hardware capabilities.
897  */
898 static void __init setup_hwcaps(void)
899 {
900 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
901 	struct cpuid cpu_id;
902 	int i;
903 
904 	/*
905 	 * The store facility list bits numbers as found in the principles
906 	 * of operation are numbered with bit 1UL<<31 as number 0 to
907 	 * bit 1UL<<0 as number 31.
908 	 *   Bit 0: instructions named N3, "backported" to esa-mode
909 	 *   Bit 2: z/Architecture mode is active
910 	 *   Bit 7: the store-facility-list-extended facility is installed
911 	 *   Bit 17: the message-security assist is installed
912 	 *   Bit 19: the long-displacement facility is installed
913 	 *   Bit 21: the extended-immediate facility is installed
914 	 *   Bit 22: extended-translation facility 3 is installed
915 	 *   Bit 30: extended-translation facility 3 enhancement facility
916 	 * These get translated to:
917 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
918 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
919 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
920 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
921 	 */
922 	for (i = 0; i < 6; i++)
923 		if (test_facility(stfl_bits[i]))
924 			elf_hwcap |= 1UL << i;
925 
926 	if (test_facility(22) && test_facility(30))
927 		elf_hwcap |= HWCAP_S390_ETF3EH;
928 
929 	/*
930 	 * Check for additional facilities with store-facility-list-extended.
931 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
932 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
933 	 * as stored by stfl, bits 32-xxx contain additional facilities.
934 	 * How many facility words are stored depends on the number of
935 	 * doublewords passed to the instruction. The additional facilities
936 	 * are:
937 	 *   Bit 42: decimal floating point facility is installed
938 	 *   Bit 44: perform floating point operation facility is installed
939 	 * translated to:
940 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
941 	 */
942 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
943 		elf_hwcap |= HWCAP_S390_DFP;
944 
945 	/*
946 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
947 	 */
948 	if (MACHINE_HAS_HPAGE)
949 		elf_hwcap |= HWCAP_S390_HPAGE;
950 
951 #if defined(CONFIG_64BIT)
952 	/*
953 	 * 64-bit register support for 31-bit processes
954 	 * HWCAP_S390_HIGH_GPRS is bit 9.
955 	 */
956 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
957 
958 	/*
959 	 * Transactional execution support HWCAP_S390_TE is bit 10.
960 	 */
961 	if (test_facility(50) && test_facility(73))
962 		elf_hwcap |= HWCAP_S390_TE;
963 #endif
964 
965 	get_cpu_id(&cpu_id);
966 	switch (cpu_id.machine) {
967 	case 0x9672:
968 #if !defined(CONFIG_64BIT)
969 	default:	/* Use "g5" as default for 31 bit kernels. */
970 #endif
971 		strcpy(elf_platform, "g5");
972 		break;
973 	case 0x2064:
974 	case 0x2066:
975 #if defined(CONFIG_64BIT)
976 	default:	/* Use "z900" as default for 64 bit kernels. */
977 #endif
978 		strcpy(elf_platform, "z900");
979 		break;
980 	case 0x2084:
981 	case 0x2086:
982 		strcpy(elf_platform, "z990");
983 		break;
984 	case 0x2094:
985 	case 0x2096:
986 		strcpy(elf_platform, "z9-109");
987 		break;
988 	case 0x2097:
989 	case 0x2098:
990 		strcpy(elf_platform, "z10");
991 		break;
992 	case 0x2817:
993 	case 0x2818:
994 		strcpy(elf_platform, "z196");
995 		break;
996 	case 0x2827:
997 	case 0x2828:
998 		strcpy(elf_platform, "zEC12");
999 		break;
1000 	}
1001 }
1002 
1003 /*
1004  * Setup function called from init/main.c just after the banner
1005  * was printed.
1006  */
1007 
1008 void __init setup_arch(char **cmdline_p)
1009 {
1010         /*
1011          * print what head.S has found out about the machine
1012          */
1013 #ifndef CONFIG_64BIT
1014 	if (MACHINE_IS_VM)
1015 		pr_info("Linux is running as a z/VM "
1016 			"guest operating system in 31-bit mode\n");
1017 	else if (MACHINE_IS_LPAR)
1018 		pr_info("Linux is running natively in 31-bit mode\n");
1019 	if (MACHINE_HAS_IEEE)
1020 		pr_info("The hardware system has IEEE compatible "
1021 			"floating point units\n");
1022 	else
1023 		pr_info("The hardware system has no IEEE compatible "
1024 			"floating point units\n");
1025 #else /* CONFIG_64BIT */
1026 	if (MACHINE_IS_VM)
1027 		pr_info("Linux is running as a z/VM "
1028 			"guest operating system in 64-bit mode\n");
1029 	else if (MACHINE_IS_KVM)
1030 		pr_info("Linux is running under KVM in 64-bit mode\n");
1031 	else if (MACHINE_IS_LPAR)
1032 		pr_info("Linux is running natively in 64-bit mode\n");
1033 #endif /* CONFIG_64BIT */
1034 
1035 	/* Have one command line that is parsed and saved in /proc/cmdline */
1036 	/* boot_command_line has been already set up in early.c */
1037 	*cmdline_p = boot_command_line;
1038 
1039         ROOT_DEV = Root_RAM0;
1040 
1041 	init_mm.start_code = PAGE_OFFSET;
1042 	init_mm.end_code = (unsigned long) &_etext;
1043 	init_mm.end_data = (unsigned long) &_edata;
1044 	init_mm.brk = (unsigned long) &_end;
1045 
1046 	if (MACHINE_HAS_MVCOS)
1047 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1048 	else
1049 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1050 
1051 	parse_early_param();
1052 	detect_memory_layout(memory_chunk, memory_end);
1053 	os_info_init();
1054 	setup_ipl();
1055 	reserve_oldmem();
1056 	setup_memory_end();
1057 	setup_addressing_mode();
1058 	reserve_crashkernel();
1059 	setup_memory();
1060 	setup_resources();
1061 	setup_vmcoreinfo();
1062 	setup_lowcore();
1063 
1064         cpu_init();
1065 	s390_init_cpu_topology();
1066 
1067 	/*
1068 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1069 	 */
1070 	setup_hwcaps();
1071 
1072 	/*
1073 	 * Create kernel page tables and switch to virtual addressing.
1074 	 */
1075         paging_init();
1076 
1077         /* Setup default console */
1078 	conmode_default();
1079 	set_preferred_console();
1080 
1081 	/* Setup zfcpdump support */
1082 	setup_zfcpdump();
1083 }
1084