xref: /openbmc/linux/arch/s390/kernel/setup.c (revision fd589a8f)
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 #include <linux/ftrace.h>
46 
47 #include <asm/ipl.h>
48 #include <asm/uaccess.h>
49 #include <asm/system.h>
50 #include <asm/smp.h>
51 #include <asm/mmu_context.h>
52 #include <asm/cpcmd.h>
53 #include <asm/lowcore.h>
54 #include <asm/irq.h>
55 #include <asm/page.h>
56 #include <asm/ptrace.h>
57 #include <asm/sections.h>
58 #include <asm/ebcdic.h>
59 #include <asm/compat.h>
60 #include <asm/kvm_virtio.h>
61 
62 long psw_kernel_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
63 			   PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
64 long psw_user_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
65 			   PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
66 			   PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
67 
68 /*
69  * User copy operations.
70  */
71 struct uaccess_ops uaccess;
72 EXPORT_SYMBOL(uaccess);
73 
74 /*
75  * Machine setup..
76  */
77 unsigned int console_mode = 0;
78 EXPORT_SYMBOL(console_mode);
79 
80 unsigned int console_devno = -1;
81 EXPORT_SYMBOL(console_devno);
82 
83 unsigned int console_irq = -1;
84 EXPORT_SYMBOL(console_irq);
85 
86 unsigned long elf_hwcap = 0;
87 char elf_platform[ELF_PLATFORM_SIZE];
88 
89 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
90 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
91 
92 int __initdata memory_end_set;
93 unsigned long __initdata memory_end;
94 
95 /* An array with a pointer to the lowcore of every CPU. */
96 struct _lowcore *lowcore_ptr[NR_CPUS];
97 EXPORT_SYMBOL(lowcore_ptr);
98 
99 /*
100  * This is set up by the setup-routine at boot-time
101  * for S390 need to find out, what we have to setup
102  * using address 0x10400 ...
103  */
104 
105 #include <asm/setup.h>
106 
107 static struct resource code_resource = {
108 	.name  = "Kernel code",
109 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
110 };
111 
112 static struct resource data_resource = {
113 	.name = "Kernel data",
114 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
115 };
116 
117 /*
118  * cpu_init() initializes state that is per-CPU.
119  */
120 void __cpuinit cpu_init(void)
121 {
122         /*
123          * Store processor id in lowcore (used e.g. in timer_interrupt)
124          */
125 	get_cpu_id(&S390_lowcore.cpu_id);
126 
127         /*
128          * Force FPU initialization:
129          */
130         clear_thread_flag(TIF_USEDFPU);
131         clear_used_math();
132 
133 	atomic_inc(&init_mm.mm_count);
134 	current->active_mm = &init_mm;
135 	BUG_ON(current->mm);
136         enter_lazy_tlb(&init_mm, current);
137 }
138 
139 /*
140  * condev= and conmode= setup parameter.
141  */
142 
143 static int __init condev_setup(char *str)
144 {
145 	int vdev;
146 
147 	vdev = simple_strtoul(str, &str, 0);
148 	if (vdev >= 0 && vdev < 65536) {
149 		console_devno = vdev;
150 		console_irq = -1;
151 	}
152 	return 1;
153 }
154 
155 __setup("condev=", condev_setup);
156 
157 static void __init set_preferred_console(void)
158 {
159 	if (MACHINE_IS_KVM)
160 		add_preferred_console("hvc", 0, NULL);
161 	else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
162 		add_preferred_console("ttyS", 0, NULL);
163 	else if (CONSOLE_IS_3270)
164 		add_preferred_console("tty3270", 0, NULL);
165 }
166 
167 static int __init conmode_setup(char *str)
168 {
169 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
170 	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
171                 SET_CONSOLE_SCLP;
172 #endif
173 #if defined(CONFIG_TN3215_CONSOLE)
174 	if (strncmp(str, "3215", 5) == 0)
175 		SET_CONSOLE_3215;
176 #endif
177 #if defined(CONFIG_TN3270_CONSOLE)
178 	if (strncmp(str, "3270", 5) == 0)
179 		SET_CONSOLE_3270;
180 #endif
181 	set_preferred_console();
182         return 1;
183 }
184 
185 __setup("conmode=", conmode_setup);
186 
187 static void __init conmode_default(void)
188 {
189 	char query_buffer[1024];
190 	char *ptr;
191 
192         if (MACHINE_IS_VM) {
193 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
194 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
195 		ptr = strstr(query_buffer, "SUBCHANNEL =");
196 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
197 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
198 		ptr = strstr(query_buffer, "CONMODE");
199 		/*
200 		 * Set the conmode to 3215 so that the device recognition
201 		 * will set the cu_type of the console to 3215. If the
202 		 * conmode is 3270 and we don't set it back then both
203 		 * 3215 and the 3270 driver will try to access the console
204 		 * device (3215 as console and 3270 as normal tty).
205 		 */
206 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
207 		if (ptr == NULL) {
208 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
209 			SET_CONSOLE_SCLP;
210 #endif
211 			return;
212 		}
213 		if (strncmp(ptr + 8, "3270", 4) == 0) {
214 #if defined(CONFIG_TN3270_CONSOLE)
215 			SET_CONSOLE_3270;
216 #elif defined(CONFIG_TN3215_CONSOLE)
217 			SET_CONSOLE_3215;
218 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
219 			SET_CONSOLE_SCLP;
220 #endif
221 		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
222 #if defined(CONFIG_TN3215_CONSOLE)
223 			SET_CONSOLE_3215;
224 #elif defined(CONFIG_TN3270_CONSOLE)
225 			SET_CONSOLE_3270;
226 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
227 			SET_CONSOLE_SCLP;
228 #endif
229 		}
230 	} else {
231 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
232 		SET_CONSOLE_SCLP;
233 #endif
234 	}
235 }
236 
237 #ifdef CONFIG_ZFCPDUMP
238 static void __init setup_zfcpdump(unsigned int console_devno)
239 {
240 	static char str[41];
241 
242 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
243 		return;
244 	if (console_devno != -1)
245 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
246 			ipl_info.data.fcp.dev_id.devno, console_devno);
247 	else
248 		sprintf(str, " cio_ignore=all,!0.0.%04x",
249 			ipl_info.data.fcp.dev_id.devno);
250 	strcat(boot_command_line, str);
251 	console_loglevel = 2;
252 }
253 #else
254 static inline void setup_zfcpdump(unsigned int console_devno) {}
255 #endif /* CONFIG_ZFCPDUMP */
256 
257  /*
258  * Reboot, halt and power_off stubs. They just call _machine_restart,
259  * _machine_halt or _machine_power_off.
260  */
261 
262 void machine_restart(char *command)
263 {
264 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
265 		/*
266 		 * Only unblank the console if we are called in enabled
267 		 * context or a bust_spinlocks cleared the way for us.
268 		 */
269 		console_unblank();
270 	_machine_restart(command);
271 }
272 
273 void machine_halt(void)
274 {
275 	if (!in_interrupt() || oops_in_progress)
276 		/*
277 		 * Only unblank the console if we are called in enabled
278 		 * context or a bust_spinlocks cleared the way for us.
279 		 */
280 		console_unblank();
281 	_machine_halt();
282 }
283 
284 void machine_power_off(void)
285 {
286 	if (!in_interrupt() || oops_in_progress)
287 		/*
288 		 * Only unblank the console if we are called in enabled
289 		 * context or a bust_spinlocks cleared the way for us.
290 		 */
291 		console_unblank();
292 	_machine_power_off();
293 }
294 
295 /*
296  * Dummy power off function.
297  */
298 void (*pm_power_off)(void) = machine_power_off;
299 
300 static int __init early_parse_mem(char *p)
301 {
302 	memory_end = memparse(p, &p);
303 	memory_end_set = 1;
304 	return 0;
305 }
306 early_param("mem", early_parse_mem);
307 
308 #ifdef CONFIG_S390_SWITCH_AMODE
309 unsigned int switch_amode = 0;
310 EXPORT_SYMBOL_GPL(switch_amode);
311 
312 static int set_amode_and_uaccess(unsigned long user_amode,
313 				 unsigned long user32_amode)
314 {
315 	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
316 			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
317 			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
318 #ifdef CONFIG_COMPAT
319 	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
320 			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
321 			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
322 	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
323 			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
324 			  PSW32_MASK_PSTATE;
325 #endif
326 	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
327 			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
328 
329 	if (MACHINE_HAS_MVCOS) {
330 		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
331 		return 1;
332 	} else {
333 		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
334 		return 0;
335 	}
336 }
337 
338 /*
339  * Switch kernel/user addressing modes?
340  */
341 static int __init early_parse_switch_amode(char *p)
342 {
343 	switch_amode = 1;
344 	return 0;
345 }
346 early_param("switch_amode", early_parse_switch_amode);
347 
348 #else /* CONFIG_S390_SWITCH_AMODE */
349 static inline int set_amode_and_uaccess(unsigned long user_amode,
350 					unsigned long user32_amode)
351 {
352 	return 0;
353 }
354 #endif /* CONFIG_S390_SWITCH_AMODE */
355 
356 #ifdef CONFIG_S390_EXEC_PROTECT
357 unsigned int s390_noexec = 0;
358 EXPORT_SYMBOL_GPL(s390_noexec);
359 
360 /*
361  * Enable execute protection?
362  */
363 static int __init early_parse_noexec(char *p)
364 {
365 	if (!strncmp(p, "off", 3))
366 		return 0;
367 	switch_amode = 1;
368 	s390_noexec = 1;
369 	return 0;
370 }
371 early_param("noexec", early_parse_noexec);
372 #endif /* CONFIG_S390_EXEC_PROTECT */
373 
374 static void setup_addressing_mode(void)
375 {
376 	if (s390_noexec) {
377 		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
378 					  PSW32_ASC_SECONDARY))
379 			pr_info("Execute protection active, "
380 				"mvcos available\n");
381 		else
382 			pr_info("Execute protection active, "
383 				"mvcos not available\n");
384 	} else if (switch_amode) {
385 		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
386 			pr_info("Address spaces switched, "
387 				"mvcos available\n");
388 		else
389 			pr_info("Address spaces switched, "
390 				"mvcos not available\n");
391 	}
392 #ifdef CONFIG_TRACE_IRQFLAGS
393 	sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
394 	io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
395 #endif
396 }
397 
398 static void __init
399 setup_lowcore(void)
400 {
401 	struct _lowcore *lc;
402 	int lc_pages;
403 
404 	/*
405 	 * Setup lowcore for boot cpu
406 	 */
407 	lc_pages = sizeof(void *) == 8 ? 2 : 1;
408 	lc = (struct _lowcore *)
409 		__alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
410 	memset(lc, 0, lc_pages * PAGE_SIZE);
411 	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
412 	lc->restart_psw.addr =
413 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
414 	if (switch_amode)
415 		lc->restart_psw.mask |= PSW_ASC_HOME;
416 	lc->external_new_psw.mask = psw_kernel_bits;
417 	lc->external_new_psw.addr =
418 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
419 	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
420 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
421 	lc->program_new_psw.mask = psw_kernel_bits;
422 	lc->program_new_psw.addr =
423 		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
424 	lc->mcck_new_psw.mask =
425 		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
426 	lc->mcck_new_psw.addr =
427 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
428 	lc->io_new_psw.mask = psw_kernel_bits;
429 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
430 	lc->clock_comparator = -1ULL;
431 	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
432 	lc->async_stack = (unsigned long)
433 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
434 	lc->panic_stack = (unsigned long)
435 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
436 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
437 	lc->thread_info = (unsigned long) &init_thread_union;
438 	lc->machine_flags = S390_lowcore.machine_flags;
439 #ifndef CONFIG_64BIT
440 	if (MACHINE_HAS_IEEE) {
441 		lc->extended_save_area_addr = (__u32)
442 			__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
443 		/* enable extended save area */
444 		__ctl_set_bit(14, 29);
445 	}
446 #else
447 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
448 #endif
449 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
450 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
451 	lc->exit_timer = S390_lowcore.exit_timer;
452 	lc->user_timer = S390_lowcore.user_timer;
453 	lc->system_timer = S390_lowcore.system_timer;
454 	lc->steal_timer = S390_lowcore.steal_timer;
455 	lc->last_update_timer = S390_lowcore.last_update_timer;
456 	lc->last_update_clock = S390_lowcore.last_update_clock;
457 	lc->ftrace_func = S390_lowcore.ftrace_func;
458 	set_prefix((u32)(unsigned long) lc);
459 	lowcore_ptr[0] = lc;
460 }
461 
462 static void __init
463 setup_resources(void)
464 {
465 	struct resource *res, *sub_res;
466 	int i;
467 
468 	code_resource.start = (unsigned long) &_text;
469 	code_resource.end = (unsigned long) &_etext - 1;
470 	data_resource.start = (unsigned long) &_etext;
471 	data_resource.end = (unsigned long) &_edata - 1;
472 
473 	for (i = 0; i < MEMORY_CHUNKS; i++) {
474 		if (!memory_chunk[i].size)
475 			continue;
476 		res = alloc_bootmem_low(sizeof(struct resource));
477 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
478 		switch (memory_chunk[i].type) {
479 		case CHUNK_READ_WRITE:
480 			res->name = "System RAM";
481 			break;
482 		case CHUNK_READ_ONLY:
483 			res->name = "System ROM";
484 			res->flags |= IORESOURCE_READONLY;
485 			break;
486 		default:
487 			res->name = "reserved";
488 		}
489 		res->start = memory_chunk[i].addr;
490 		res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
491 		request_resource(&iomem_resource, res);
492 
493 		if (code_resource.start >= res->start  &&
494 			code_resource.start <= res->end &&
495 			code_resource.end > res->end) {
496 			sub_res = alloc_bootmem_low(sizeof(struct resource));
497 			memcpy(sub_res, &code_resource,
498 				sizeof(struct resource));
499 			sub_res->end = res->end;
500 			code_resource.start = res->end + 1;
501 			request_resource(res, sub_res);
502 		}
503 
504 		if (code_resource.start >= res->start &&
505 			code_resource.start <= res->end &&
506 			code_resource.end <= res->end)
507 			request_resource(res, &code_resource);
508 
509 		if (data_resource.start >= res->start &&
510 			data_resource.start <= res->end &&
511 			data_resource.end > res->end) {
512 			sub_res = alloc_bootmem_low(sizeof(struct resource));
513 			memcpy(sub_res, &data_resource,
514 				sizeof(struct resource));
515 			sub_res->end = res->end;
516 			data_resource.start = res->end + 1;
517 			request_resource(res, sub_res);
518 		}
519 
520 		if (data_resource.start >= res->start &&
521 			data_resource.start <= res->end &&
522 			data_resource.end <= res->end)
523 			request_resource(res, &data_resource);
524 	}
525 }
526 
527 unsigned long real_memory_size;
528 EXPORT_SYMBOL_GPL(real_memory_size);
529 
530 static void __init setup_memory_end(void)
531 {
532 	unsigned long memory_size;
533 	unsigned long max_mem;
534 	int i;
535 
536 #ifdef CONFIG_ZFCPDUMP
537 	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
538 		memory_end = ZFCPDUMP_HSA_SIZE;
539 		memory_end_set = 1;
540 	}
541 #endif
542 	memory_size = 0;
543 	memory_end &= PAGE_MASK;
544 
545 	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
546 	memory_end = min(max_mem, memory_end);
547 
548 	/*
549 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
550 	 * extra checks that HOLES_IN_ZONE would require.
551 	 */
552 	for (i = 0; i < MEMORY_CHUNKS; i++) {
553 		unsigned long start, end;
554 		struct mem_chunk *chunk;
555 		unsigned long align;
556 
557 		chunk = &memory_chunk[i];
558 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
559 		start = (chunk->addr + align - 1) & ~(align - 1);
560 		end = (chunk->addr + chunk->size) & ~(align - 1);
561 		if (start >= end)
562 			memset(chunk, 0, sizeof(*chunk));
563 		else {
564 			chunk->addr = start;
565 			chunk->size = end - start;
566 		}
567 	}
568 
569 	for (i = 0; i < MEMORY_CHUNKS; i++) {
570 		struct mem_chunk *chunk = &memory_chunk[i];
571 
572 		real_memory_size = max(real_memory_size,
573 				       chunk->addr + chunk->size);
574 		if (chunk->addr >= max_mem) {
575 			memset(chunk, 0, sizeof(*chunk));
576 			continue;
577 		}
578 		if (chunk->addr + chunk->size > max_mem)
579 			chunk->size = max_mem - chunk->addr;
580 		memory_size = max(memory_size, chunk->addr + chunk->size);
581 	}
582 	if (!memory_end)
583 		memory_end = memory_size;
584 }
585 
586 static void __init
587 setup_memory(void)
588 {
589         unsigned long bootmap_size;
590 	unsigned long start_pfn, end_pfn;
591 	int i;
592 
593 	/*
594 	 * partially used pages are not usable - thus
595 	 * we are rounding upwards:
596 	 */
597 	start_pfn = PFN_UP(__pa(&_end));
598 	end_pfn = max_pfn = PFN_DOWN(memory_end);
599 
600 #ifdef CONFIG_BLK_DEV_INITRD
601 	/*
602 	 * Move the initrd in case the bitmap of the bootmem allocater
603 	 * would overwrite it.
604 	 */
605 
606 	if (INITRD_START && INITRD_SIZE) {
607 		unsigned long bmap_size;
608 		unsigned long start;
609 
610 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
611 		bmap_size = PFN_PHYS(bmap_size);
612 
613 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
614 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
615 
616 			if (start + INITRD_SIZE > memory_end) {
617 				pr_err("initrd extends beyond end of "
618 				       "memory (0x%08lx > 0x%08lx) "
619 				       "disabling initrd\n",
620 				       start + INITRD_SIZE, memory_end);
621 				INITRD_START = INITRD_SIZE = 0;
622 			} else {
623 				pr_info("Moving initrd (0x%08lx -> "
624 					"0x%08lx, size: %ld)\n",
625 					INITRD_START, start, INITRD_SIZE);
626 				memmove((void *) start, (void *) INITRD_START,
627 					INITRD_SIZE);
628 				INITRD_START = start;
629 			}
630 		}
631 	}
632 #endif
633 
634 	/*
635 	 * Initialize the boot-time allocator
636 	 */
637 	bootmap_size = init_bootmem(start_pfn, end_pfn);
638 
639 	/*
640 	 * Register RAM areas with the bootmem allocator.
641 	 */
642 
643 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
644 		unsigned long start_chunk, end_chunk, pfn;
645 
646 		if (memory_chunk[i].type != CHUNK_READ_WRITE)
647 			continue;
648 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
649 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
650 		end_chunk = min(end_chunk, end_pfn);
651 		if (start_chunk >= end_chunk)
652 			continue;
653 		add_active_range(0, start_chunk, end_chunk);
654 		pfn = max(start_chunk, start_pfn);
655 		for (; pfn < end_chunk; pfn++)
656 			page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
657 	}
658 
659 	psw_set_key(PAGE_DEFAULT_KEY);
660 
661 	free_bootmem_with_active_regions(0, max_pfn);
662 
663 	/*
664 	 * Reserve memory used for lowcore/command line/kernel image.
665 	 */
666 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
667 	reserve_bootmem((unsigned long)_stext,
668 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
669 			BOOTMEM_DEFAULT);
670 	/*
671 	 * Reserve the bootmem bitmap itself as well. We do this in two
672 	 * steps (first step was init_bootmem()) because this catches
673 	 * the (very unlikely) case of us accidentally initializing the
674 	 * bootmem allocator with an invalid RAM area.
675 	 */
676 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
677 			BOOTMEM_DEFAULT);
678 
679 #ifdef CONFIG_BLK_DEV_INITRD
680 	if (INITRD_START && INITRD_SIZE) {
681 		if (INITRD_START + INITRD_SIZE <= memory_end) {
682 			reserve_bootmem(INITRD_START, INITRD_SIZE,
683 					BOOTMEM_DEFAULT);
684 			initrd_start = INITRD_START;
685 			initrd_end = initrd_start + INITRD_SIZE;
686 		} else {
687 			pr_err("initrd extends beyond end of "
688 			       "memory (0x%08lx > 0x%08lx) "
689 			       "disabling initrd\n",
690 			       initrd_start + INITRD_SIZE, memory_end);
691 			initrd_start = initrd_end = 0;
692 		}
693 	}
694 #endif
695 }
696 
697 /*
698  * Setup hardware capabilities.
699  */
700 static void __init setup_hwcaps(void)
701 {
702 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
703 	unsigned long long facility_list_extended;
704 	unsigned int facility_list;
705 	int i;
706 
707 	facility_list = stfl();
708 	/*
709 	 * The store facility list bits numbers as found in the principles
710 	 * of operation are numbered with bit 1UL<<31 as number 0 to
711 	 * bit 1UL<<0 as number 31.
712 	 *   Bit 0: instructions named N3, "backported" to esa-mode
713 	 *   Bit 2: z/Architecture mode is active
714 	 *   Bit 7: the store-facility-list-extended facility is installed
715 	 *   Bit 17: the message-security assist is installed
716 	 *   Bit 19: the long-displacement facility is installed
717 	 *   Bit 21: the extended-immediate facility is installed
718 	 *   Bit 22: extended-translation facility 3 is installed
719 	 *   Bit 30: extended-translation facility 3 enhancement facility
720 	 * These get translated to:
721 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
722 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
723 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
724 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
725 	 */
726 	for (i = 0; i < 6; i++)
727 		if (facility_list & (1UL << (31 - stfl_bits[i])))
728 			elf_hwcap |= 1UL << i;
729 
730 	if ((facility_list & (1UL << (31 - 22)))
731 	    && (facility_list & (1UL << (31 - 30))))
732 		elf_hwcap |= 1UL << 8;
733 
734 	/*
735 	 * Check for additional facilities with store-facility-list-extended.
736 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
737 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
738 	 * as stored by stfl, bits 32-xxx contain additional facilities.
739 	 * How many facility words are stored depends on the number of
740 	 * doublewords passed to the instruction. The additional facilites
741 	 * are:
742 	 *   Bit 42: decimal floating point facility is installed
743 	 *   Bit 44: perform floating point operation facility is installed
744 	 * translated to:
745 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
746 	 */
747 	if ((elf_hwcap & (1UL << 2)) &&
748 	    __stfle(&facility_list_extended, 1) > 0) {
749 		if ((facility_list_extended & (1ULL << (63 - 42)))
750 		    && (facility_list_extended & (1ULL << (63 - 44))))
751 			elf_hwcap |= 1UL << 6;
752 	}
753 
754 	if (MACHINE_HAS_HPAGE)
755 		elf_hwcap |= 1UL << 7;
756 
757 	switch (S390_lowcore.cpu_id.machine) {
758 	case 0x9672:
759 #if !defined(CONFIG_64BIT)
760 	default:	/* Use "g5" as default for 31 bit kernels. */
761 #endif
762 		strcpy(elf_platform, "g5");
763 		break;
764 	case 0x2064:
765 	case 0x2066:
766 #if defined(CONFIG_64BIT)
767 	default:	/* Use "z900" as default for 64 bit kernels. */
768 #endif
769 		strcpy(elf_platform, "z900");
770 		break;
771 	case 0x2084:
772 	case 0x2086:
773 		strcpy(elf_platform, "z990");
774 		break;
775 	case 0x2094:
776 	case 0x2096:
777 		strcpy(elf_platform, "z9-109");
778 		break;
779 	case 0x2097:
780 	case 0x2098:
781 		strcpy(elf_platform, "z10");
782 		break;
783 	}
784 }
785 
786 /*
787  * Setup function called from init/main.c just after the banner
788  * was printed.
789  */
790 
791 void __init
792 setup_arch(char **cmdline_p)
793 {
794         /*
795          * print what head.S has found out about the machine
796          */
797 #ifndef CONFIG_64BIT
798 	if (MACHINE_IS_VM)
799 		pr_info("Linux is running as a z/VM "
800 			"guest operating system in 31-bit mode\n");
801 	else
802 		pr_info("Linux is running natively in 31-bit mode\n");
803 	if (MACHINE_HAS_IEEE)
804 		pr_info("The hardware system has IEEE compatible "
805 			"floating point units\n");
806 	else
807 		pr_info("The hardware system has no IEEE compatible "
808 			"floating point units\n");
809 #else /* CONFIG_64BIT */
810 	if (MACHINE_IS_VM)
811 		pr_info("Linux is running as a z/VM "
812 			"guest operating system in 64-bit mode\n");
813 	else if (MACHINE_IS_KVM)
814 		pr_info("Linux is running under KVM in 64-bit mode\n");
815 	else
816 		pr_info("Linux is running natively in 64-bit mode\n");
817 #endif /* CONFIG_64BIT */
818 
819 	/* Have one command line that is parsed and saved in /proc/cmdline */
820 	/* boot_command_line has been already set up in early.c */
821 	*cmdline_p = boot_command_line;
822 
823         ROOT_DEV = Root_RAM0;
824 
825 	init_mm.start_code = PAGE_OFFSET;
826 	init_mm.end_code = (unsigned long) &_etext;
827 	init_mm.end_data = (unsigned long) &_edata;
828 	init_mm.brk = (unsigned long) &_end;
829 
830 	if (MACHINE_HAS_MVCOS)
831 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
832 	else
833 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
834 
835 	parse_early_param();
836 
837 	setup_ipl();
838 	setup_memory_end();
839 	setup_addressing_mode();
840 	setup_memory();
841 	setup_resources();
842 	setup_lowcore();
843 
844         cpu_init();
845 	__cpu_logical_map[0] = stap();
846 	s390_init_cpu_topology();
847 
848 	/*
849 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
850 	 */
851 	setup_hwcaps();
852 
853 	/*
854 	 * Create kernel page tables and switch to virtual addressing.
855 	 */
856         paging_init();
857 
858         /* Setup default console */
859 	conmode_default();
860 	set_preferred_console();
861 
862 	/* Setup zfcpdump support */
863 	setup_zfcpdump(console_devno);
864 }
865