1 /*
2  *  arch/s390/kernel/setup.c
3  *
4  *  S390 version
5  *    Copyright (C) IBM Corp. 1999,2010
6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "arch/i386/kernel/setup.c"
10  *    Copyright (C) 1995, Linus Torvalds
11  */
12 
13 /*
14  * This file handles the architecture-dependent parts of initialization
15  */
16 
17 #define KMSG_COMPONENT "setup"
18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
19 
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/stddef.h>
26 #include <linux/unistd.h>
27 #include <linux/ptrace.h>
28 #include <linux/user.h>
29 #include <linux/tty.h>
30 #include <linux/ioport.h>
31 #include <linux/delay.h>
32 #include <linux/init.h>
33 #include <linux/initrd.h>
34 #include <linux/bootmem.h>
35 #include <linux/root_dev.h>
36 #include <linux/console.h>
37 #include <linux/kernel_stat.h>
38 #include <linux/device.h>
39 #include <linux/notifier.h>
40 #include <linux/pfn.h>
41 #include <linux/ctype.h>
42 #include <linux/reboot.h>
43 #include <linux/topology.h>
44 #include <linux/ftrace.h>
45 
46 #include <asm/ipl.h>
47 #include <asm/uaccess.h>
48 #include <asm/system.h>
49 #include <asm/smp.h>
50 #include <asm/mmu_context.h>
51 #include <asm/cpcmd.h>
52 #include <asm/lowcore.h>
53 #include <asm/irq.h>
54 #include <asm/page.h>
55 #include <asm/ptrace.h>
56 #include <asm/sections.h>
57 #include <asm/ebcdic.h>
58 #include <asm/compat.h>
59 #include <asm/kvm_virtio.h>
60 
61 long psw_kernel_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
62 			   PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
63 long psw_user_bits	= (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
64 			   PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
65 			   PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
66 
67 /*
68  * User copy operations.
69  */
70 struct uaccess_ops uaccess;
71 EXPORT_SYMBOL(uaccess);
72 
73 /*
74  * Machine setup..
75  */
76 unsigned int console_mode = 0;
77 EXPORT_SYMBOL(console_mode);
78 
79 unsigned int console_devno = -1;
80 EXPORT_SYMBOL(console_devno);
81 
82 unsigned int console_irq = -1;
83 EXPORT_SYMBOL(console_irq);
84 
85 unsigned long elf_hwcap = 0;
86 char elf_platform[ELF_PLATFORM_SIZE];
87 
88 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
89 
90 int __initdata memory_end_set;
91 unsigned long __initdata memory_end;
92 
93 /* An array with a pointer to the lowcore of every CPU. */
94 struct _lowcore *lowcore_ptr[NR_CPUS];
95 EXPORT_SYMBOL(lowcore_ptr);
96 
97 /*
98  * This is set up by the setup-routine at boot-time
99  * for S390 need to find out, what we have to setup
100  * using address 0x10400 ...
101  */
102 
103 #include <asm/setup.h>
104 
105 /*
106  * condev= and conmode= setup parameter.
107  */
108 
condev_setup(char * str)109 static int __init condev_setup(char *str)
110 {
111 	int vdev;
112 
113 	vdev = simple_strtoul(str, &str, 0);
114 	if (vdev >= 0 && vdev < 65536) {
115 		console_devno = vdev;
116 		console_irq = -1;
117 	}
118 	return 1;
119 }
120 
121 __setup("condev=", condev_setup);
122 
set_preferred_console(void)123 static void __init set_preferred_console(void)
124 {
125 	if (MACHINE_IS_KVM)
126 		add_preferred_console("hvc", 0, NULL);
127 	else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
128 		add_preferred_console("ttyS", 0, NULL);
129 	else if (CONSOLE_IS_3270)
130 		add_preferred_console("tty3270", 0, NULL);
131 }
132 
conmode_setup(char * str)133 static int __init conmode_setup(char *str)
134 {
135 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
136 	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
137                 SET_CONSOLE_SCLP;
138 #endif
139 #if defined(CONFIG_TN3215_CONSOLE)
140 	if (strncmp(str, "3215", 5) == 0)
141 		SET_CONSOLE_3215;
142 #endif
143 #if defined(CONFIG_TN3270_CONSOLE)
144 	if (strncmp(str, "3270", 5) == 0)
145 		SET_CONSOLE_3270;
146 #endif
147 	set_preferred_console();
148         return 1;
149 }
150 
151 __setup("conmode=", conmode_setup);
152 
conmode_default(void)153 static void __init conmode_default(void)
154 {
155 	char query_buffer[1024];
156 	char *ptr;
157 
158         if (MACHINE_IS_VM) {
159 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
160 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
161 		ptr = strstr(query_buffer, "SUBCHANNEL =");
162 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
163 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
164 		ptr = strstr(query_buffer, "CONMODE");
165 		/*
166 		 * Set the conmode to 3215 so that the device recognition
167 		 * will set the cu_type of the console to 3215. If the
168 		 * conmode is 3270 and we don't set it back then both
169 		 * 3215 and the 3270 driver will try to access the console
170 		 * device (3215 as console and 3270 as normal tty).
171 		 */
172 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
173 		if (ptr == NULL) {
174 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
175 			SET_CONSOLE_SCLP;
176 #endif
177 			return;
178 		}
179 		if (strncmp(ptr + 8, "3270", 4) == 0) {
180 #if defined(CONFIG_TN3270_CONSOLE)
181 			SET_CONSOLE_3270;
182 #elif defined(CONFIG_TN3215_CONSOLE)
183 			SET_CONSOLE_3215;
184 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
185 			SET_CONSOLE_SCLP;
186 #endif
187 		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
188 #if defined(CONFIG_TN3215_CONSOLE)
189 			SET_CONSOLE_3215;
190 #elif defined(CONFIG_TN3270_CONSOLE)
191 			SET_CONSOLE_3270;
192 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
193 			SET_CONSOLE_SCLP;
194 #endif
195 		}
196 	} else {
197 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
198 		SET_CONSOLE_SCLP;
199 #endif
200 	}
201 }
202 
203 #ifdef CONFIG_ZFCPDUMP
setup_zfcpdump(unsigned int console_devno)204 static void __init setup_zfcpdump(unsigned int console_devno)
205 {
206 	static char str[41];
207 
208 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
209 		return;
210 	if (console_devno != -1)
211 		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
212 			ipl_info.data.fcp.dev_id.devno, console_devno);
213 	else
214 		sprintf(str, " cio_ignore=all,!0.0.%04x",
215 			ipl_info.data.fcp.dev_id.devno);
216 	strcat(boot_command_line, str);
217 	console_loglevel = 2;
218 }
219 #else
setup_zfcpdump(unsigned int console_devno)220 static inline void setup_zfcpdump(unsigned int console_devno) {}
221 #endif /* CONFIG_ZFCPDUMP */
222 
223  /*
224  * Reboot, halt and power_off stubs. They just call _machine_restart,
225  * _machine_halt or _machine_power_off.
226  */
227 
machine_restart(char * command)228 void machine_restart(char *command)
229 {
230 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
231 		/*
232 		 * Only unblank the console if we are called in enabled
233 		 * context or a bust_spinlocks cleared the way for us.
234 		 */
235 		console_unblank();
236 	_machine_restart(command);
237 }
238 
machine_halt(void)239 void machine_halt(void)
240 {
241 	if (!in_interrupt() || oops_in_progress)
242 		/*
243 		 * Only unblank the console if we are called in enabled
244 		 * context or a bust_spinlocks cleared the way for us.
245 		 */
246 		console_unblank();
247 	_machine_halt();
248 }
249 
machine_power_off(void)250 void machine_power_off(void)
251 {
252 	if (!in_interrupt() || oops_in_progress)
253 		/*
254 		 * Only unblank the console if we are called in enabled
255 		 * context or a bust_spinlocks cleared the way for us.
256 		 */
257 		console_unblank();
258 	_machine_power_off();
259 }
260 
261 /*
262  * Dummy power off function.
263  */
264 void (*pm_power_off)(void) = machine_power_off;
265 
early_parse_mem(char * p)266 static int __init early_parse_mem(char *p)
267 {
268 	memory_end = memparse(p, &p);
269 	memory_end_set = 1;
270 	return 0;
271 }
272 early_param("mem", early_parse_mem);
273 
274 unsigned int user_mode = HOME_SPACE_MODE;
275 EXPORT_SYMBOL_GPL(user_mode);
276 
set_amode_and_uaccess(unsigned long user_amode,unsigned long user32_amode)277 static int set_amode_and_uaccess(unsigned long user_amode,
278 				 unsigned long user32_amode)
279 {
280 	psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
281 			PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
282 			PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
283 #ifdef CONFIG_COMPAT
284 	psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
285 			  PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
286 			  PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
287 	psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
288 			  PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
289 			  PSW32_MASK_PSTATE;
290 #endif
291 	psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
292 			  PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
293 
294 	if (MACHINE_HAS_MVCOS) {
295 		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
296 		return 1;
297 	} else {
298 		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
299 		return 0;
300 	}
301 }
302 
303 /*
304  * Switch kernel/user addressing modes?
305  */
early_parse_switch_amode(char * p)306 static int __init early_parse_switch_amode(char *p)
307 {
308 	if (user_mode != SECONDARY_SPACE_MODE)
309 		user_mode = PRIMARY_SPACE_MODE;
310 	return 0;
311 }
312 early_param("switch_amode", early_parse_switch_amode);
313 
early_parse_user_mode(char * p)314 static int __init early_parse_user_mode(char *p)
315 {
316 	if (p && strcmp(p, "primary") == 0)
317 		user_mode = PRIMARY_SPACE_MODE;
318 #ifdef CONFIG_S390_EXEC_PROTECT
319 	else if (p && strcmp(p, "secondary") == 0)
320 		user_mode = SECONDARY_SPACE_MODE;
321 #endif
322 	else if (!p || strcmp(p, "home") == 0)
323 		user_mode = HOME_SPACE_MODE;
324 	else
325 		return 1;
326 	return 0;
327 }
328 early_param("user_mode", early_parse_user_mode);
329 
330 #ifdef CONFIG_S390_EXEC_PROTECT
331 /*
332  * Enable execute protection?
333  */
early_parse_noexec(char * p)334 static int __init early_parse_noexec(char *p)
335 {
336 	if (!strncmp(p, "off", 3))
337 		return 0;
338 	user_mode = SECONDARY_SPACE_MODE;
339 	return 0;
340 }
341 early_param("noexec", early_parse_noexec);
342 #endif /* CONFIG_S390_EXEC_PROTECT */
343 
setup_addressing_mode(void)344 static void setup_addressing_mode(void)
345 {
346 	if (user_mode == SECONDARY_SPACE_MODE) {
347 		if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
348 					  PSW32_ASC_SECONDARY))
349 			pr_info("Execute protection active, "
350 				"mvcos available\n");
351 		else
352 			pr_info("Execute protection active, "
353 				"mvcos not available\n");
354 	} else if (user_mode == PRIMARY_SPACE_MODE) {
355 		if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
356 			pr_info("Address spaces switched, "
357 				"mvcos available\n");
358 		else
359 			pr_info("Address spaces switched, "
360 				"mvcos not available\n");
361 	}
362 }
363 
364 static void __init
setup_lowcore(void)365 setup_lowcore(void)
366 {
367 	struct _lowcore *lc;
368 
369 	/*
370 	 * Setup lowcore for boot cpu
371 	 */
372 	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
373 	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
374 	lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
375 	lc->restart_psw.addr =
376 		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
377 	if (user_mode != HOME_SPACE_MODE)
378 		lc->restart_psw.mask |= PSW_ASC_HOME;
379 	lc->external_new_psw.mask = psw_kernel_bits;
380 	lc->external_new_psw.addr =
381 		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
382 	lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
383 	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
384 	lc->program_new_psw.mask = psw_kernel_bits;
385 	lc->program_new_psw.addr =
386 		PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
387 	lc->mcck_new_psw.mask =
388 		psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
389 	lc->mcck_new_psw.addr =
390 		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
391 	lc->io_new_psw.mask = psw_kernel_bits;
392 	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
393 	lc->clock_comparator = -1ULL;
394 	lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
395 	lc->async_stack = (unsigned long)
396 		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
397 	lc->panic_stack = (unsigned long)
398 		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
399 	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
400 	lc->thread_info = (unsigned long) &init_thread_union;
401 	lc->machine_flags = S390_lowcore.machine_flags;
402 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
403 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
404 	       MAX_FACILITY_BIT/8);
405 #ifndef CONFIG_64BIT
406 	if (MACHINE_HAS_IEEE) {
407 		lc->extended_save_area_addr = (__u32)
408 			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
409 		/* enable extended save area */
410 		__ctl_set_bit(14, 29);
411 	}
412 #else
413 	lc->cmf_hpp = -1ULL;
414 	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
415 #endif
416 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
417 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
418 	lc->exit_timer = S390_lowcore.exit_timer;
419 	lc->user_timer = S390_lowcore.user_timer;
420 	lc->system_timer = S390_lowcore.system_timer;
421 	lc->steal_timer = S390_lowcore.steal_timer;
422 	lc->last_update_timer = S390_lowcore.last_update_timer;
423 	lc->last_update_clock = S390_lowcore.last_update_clock;
424 	lc->ftrace_func = S390_lowcore.ftrace_func;
425 	set_prefix((u32)(unsigned long) lc);
426 	lowcore_ptr[0] = lc;
427 }
428 
429 static struct resource code_resource = {
430 	.name  = "Kernel code",
431 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
432 };
433 
434 static struct resource data_resource = {
435 	.name = "Kernel data",
436 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
437 };
438 
439 static struct resource bss_resource = {
440 	.name = "Kernel bss",
441 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
442 };
443 
444 static struct resource __initdata *standard_resources[] = {
445 	&code_resource,
446 	&data_resource,
447 	&bss_resource,
448 };
449 
setup_resources(void)450 static void __init setup_resources(void)
451 {
452 	struct resource *res, *std_res, *sub_res;
453 	int i, j;
454 
455 	code_resource.start = (unsigned long) &_text;
456 	code_resource.end = (unsigned long) &_etext - 1;
457 	data_resource.start = (unsigned long) &_etext;
458 	data_resource.end = (unsigned long) &_edata - 1;
459 	bss_resource.start = (unsigned long) &__bss_start;
460 	bss_resource.end = (unsigned long) &__bss_stop - 1;
461 
462 	for (i = 0; i < MEMORY_CHUNKS; i++) {
463 		if (!memory_chunk[i].size)
464 			continue;
465 		res = alloc_bootmem_low(sizeof(*res));
466 		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
467 		switch (memory_chunk[i].type) {
468 		case CHUNK_READ_WRITE:
469 			res->name = "System RAM";
470 			break;
471 		case CHUNK_READ_ONLY:
472 			res->name = "System ROM";
473 			res->flags |= IORESOURCE_READONLY;
474 			break;
475 		default:
476 			res->name = "reserved";
477 		}
478 		res->start = memory_chunk[i].addr;
479 		res->end = res->start + memory_chunk[i].size - 1;
480 		request_resource(&iomem_resource, res);
481 
482 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
483 			std_res = standard_resources[j];
484 			if (std_res->start < res->start ||
485 			    std_res->start > res->end)
486 				continue;
487 			if (std_res->end > res->end) {
488 				sub_res = alloc_bootmem_low(sizeof(*sub_res));
489 				*sub_res = *std_res;
490 				sub_res->end = res->end;
491 				std_res->start = res->end + 1;
492 				request_resource(res, sub_res);
493 			} else {
494 				request_resource(res, std_res);
495 			}
496 		}
497 	}
498 }
499 
500 unsigned long real_memory_size;
501 EXPORT_SYMBOL_GPL(real_memory_size);
502 
setup_memory_end(void)503 static void __init setup_memory_end(void)
504 {
505 	unsigned long memory_size;
506 	unsigned long max_mem;
507 	int i;
508 
509 #ifdef CONFIG_ZFCPDUMP
510 	if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
511 		memory_end = ZFCPDUMP_HSA_SIZE;
512 		memory_end_set = 1;
513 	}
514 #endif
515 	memory_size = 0;
516 	memory_end &= PAGE_MASK;
517 
518 	max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
519 	memory_end = min(max_mem, memory_end);
520 
521 	/*
522 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
523 	 * extra checks that HOLES_IN_ZONE would require.
524 	 */
525 	for (i = 0; i < MEMORY_CHUNKS; i++) {
526 		unsigned long start, end;
527 		struct mem_chunk *chunk;
528 		unsigned long align;
529 
530 		chunk = &memory_chunk[i];
531 		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
532 		start = (chunk->addr + align - 1) & ~(align - 1);
533 		end = (chunk->addr + chunk->size) & ~(align - 1);
534 		if (start >= end)
535 			memset(chunk, 0, sizeof(*chunk));
536 		else {
537 			chunk->addr = start;
538 			chunk->size = end - start;
539 		}
540 	}
541 
542 	for (i = 0; i < MEMORY_CHUNKS; i++) {
543 		struct mem_chunk *chunk = &memory_chunk[i];
544 
545 		real_memory_size = max(real_memory_size,
546 				       chunk->addr + chunk->size);
547 		if (chunk->addr >= max_mem) {
548 			memset(chunk, 0, sizeof(*chunk));
549 			continue;
550 		}
551 		if (chunk->addr + chunk->size > max_mem)
552 			chunk->size = max_mem - chunk->addr;
553 		memory_size = max(memory_size, chunk->addr + chunk->size);
554 	}
555 	if (!memory_end)
556 		memory_end = memory_size;
557 }
558 
559 static void __init
setup_memory(void)560 setup_memory(void)
561 {
562         unsigned long bootmap_size;
563 	unsigned long start_pfn, end_pfn;
564 	int i;
565 
566 	/*
567 	 * partially used pages are not usable - thus
568 	 * we are rounding upwards:
569 	 */
570 	start_pfn = PFN_UP(__pa(&_end));
571 	end_pfn = max_pfn = PFN_DOWN(memory_end);
572 
573 #ifdef CONFIG_BLK_DEV_INITRD
574 	/*
575 	 * Move the initrd in case the bitmap of the bootmem allocater
576 	 * would overwrite it.
577 	 */
578 
579 	if (INITRD_START && INITRD_SIZE) {
580 		unsigned long bmap_size;
581 		unsigned long start;
582 
583 		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
584 		bmap_size = PFN_PHYS(bmap_size);
585 
586 		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
587 			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
588 
589 			if (start + INITRD_SIZE > memory_end) {
590 				pr_err("initrd extends beyond end of "
591 				       "memory (0x%08lx > 0x%08lx) "
592 				       "disabling initrd\n",
593 				       start + INITRD_SIZE, memory_end);
594 				INITRD_START = INITRD_SIZE = 0;
595 			} else {
596 				pr_info("Moving initrd (0x%08lx -> "
597 					"0x%08lx, size: %ld)\n",
598 					INITRD_START, start, INITRD_SIZE);
599 				memmove((void *) start, (void *) INITRD_START,
600 					INITRD_SIZE);
601 				INITRD_START = start;
602 			}
603 		}
604 	}
605 #endif
606 
607 	/*
608 	 * Initialize the boot-time allocator
609 	 */
610 	bootmap_size = init_bootmem(start_pfn, end_pfn);
611 
612 	/*
613 	 * Register RAM areas with the bootmem allocator.
614 	 */
615 
616 	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
617 		unsigned long start_chunk, end_chunk, pfn;
618 
619 		if (memory_chunk[i].type != CHUNK_READ_WRITE)
620 			continue;
621 		start_chunk = PFN_DOWN(memory_chunk[i].addr);
622 		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
623 		end_chunk = min(end_chunk, end_pfn);
624 		if (start_chunk >= end_chunk)
625 			continue;
626 		add_active_range(0, start_chunk, end_chunk);
627 		pfn = max(start_chunk, start_pfn);
628 		for (; pfn < end_chunk; pfn++)
629 			page_set_storage_key(PFN_PHYS(pfn),
630 					     PAGE_DEFAULT_KEY, 0);
631 	}
632 
633 	psw_set_key(PAGE_DEFAULT_KEY);
634 
635 	free_bootmem_with_active_regions(0, max_pfn);
636 
637 	/*
638 	 * Reserve memory used for lowcore/command line/kernel image.
639 	 */
640 	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
641 	reserve_bootmem((unsigned long)_stext,
642 			PFN_PHYS(start_pfn) - (unsigned long)_stext,
643 			BOOTMEM_DEFAULT);
644 	/*
645 	 * Reserve the bootmem bitmap itself as well. We do this in two
646 	 * steps (first step was init_bootmem()) because this catches
647 	 * the (very unlikely) case of us accidentally initializing the
648 	 * bootmem allocator with an invalid RAM area.
649 	 */
650 	reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
651 			BOOTMEM_DEFAULT);
652 
653 #ifdef CONFIG_BLK_DEV_INITRD
654 	if (INITRD_START && INITRD_SIZE) {
655 		if (INITRD_START + INITRD_SIZE <= memory_end) {
656 			reserve_bootmem(INITRD_START, INITRD_SIZE,
657 					BOOTMEM_DEFAULT);
658 			initrd_start = INITRD_START;
659 			initrd_end = initrd_start + INITRD_SIZE;
660 		} else {
661 			pr_err("initrd extends beyond end of "
662 			       "memory (0x%08lx > 0x%08lx) "
663 			       "disabling initrd\n",
664 			       initrd_start + INITRD_SIZE, memory_end);
665 			initrd_start = initrd_end = 0;
666 		}
667 	}
668 #endif
669 }
670 
671 /*
672  * Setup hardware capabilities.
673  */
setup_hwcaps(void)674 static void __init setup_hwcaps(void)
675 {
676 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
677 	struct cpuid cpu_id;
678 	int i;
679 
680 	/*
681 	 * The store facility list bits numbers as found in the principles
682 	 * of operation are numbered with bit 1UL<<31 as number 0 to
683 	 * bit 1UL<<0 as number 31.
684 	 *   Bit 0: instructions named N3, "backported" to esa-mode
685 	 *   Bit 2: z/Architecture mode is active
686 	 *   Bit 7: the store-facility-list-extended facility is installed
687 	 *   Bit 17: the message-security assist is installed
688 	 *   Bit 19: the long-displacement facility is installed
689 	 *   Bit 21: the extended-immediate facility is installed
690 	 *   Bit 22: extended-translation facility 3 is installed
691 	 *   Bit 30: extended-translation facility 3 enhancement facility
692 	 * These get translated to:
693 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
694 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
695 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
696 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
697 	 */
698 	for (i = 0; i < 6; i++)
699 		if (test_facility(stfl_bits[i]))
700 			elf_hwcap |= 1UL << i;
701 
702 	if (test_facility(22) && test_facility(30))
703 		elf_hwcap |= HWCAP_S390_ETF3EH;
704 
705 	/*
706 	 * Check for additional facilities with store-facility-list-extended.
707 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
708 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
709 	 * as stored by stfl, bits 32-xxx contain additional facilities.
710 	 * How many facility words are stored depends on the number of
711 	 * doublewords passed to the instruction. The additional facilities
712 	 * are:
713 	 *   Bit 42: decimal floating point facility is installed
714 	 *   Bit 44: perform floating point operation facility is installed
715 	 * translated to:
716 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
717 	 */
718 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
719 		elf_hwcap |= HWCAP_S390_DFP;
720 
721 	/*
722 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
723 	 */
724 	if (MACHINE_HAS_HPAGE)
725 		elf_hwcap |= HWCAP_S390_HPAGE;
726 
727 	/*
728 	 * 64-bit register support for 31-bit processes
729 	 * HWCAP_S390_HIGH_GPRS is bit 9.
730 	 */
731 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
732 
733 	get_cpu_id(&cpu_id);
734 	switch (cpu_id.machine) {
735 	case 0x9672:
736 #if !defined(CONFIG_64BIT)
737 	default:	/* Use "g5" as default for 31 bit kernels. */
738 #endif
739 		strcpy(elf_platform, "g5");
740 		break;
741 	case 0x2064:
742 	case 0x2066:
743 #if defined(CONFIG_64BIT)
744 	default:	/* Use "z900" as default for 64 bit kernels. */
745 #endif
746 		strcpy(elf_platform, "z900");
747 		break;
748 	case 0x2084:
749 	case 0x2086:
750 		strcpy(elf_platform, "z990");
751 		break;
752 	case 0x2094:
753 	case 0x2096:
754 		strcpy(elf_platform, "z9-109");
755 		break;
756 	case 0x2097:
757 	case 0x2098:
758 		strcpy(elf_platform, "z10");
759 		break;
760 	case 0x2817:
761 		strcpy(elf_platform, "z196");
762 		break;
763 	}
764 }
765 
766 /*
767  * Setup function called from init/main.c just after the banner
768  * was printed.
769  */
770 
771 void __init
setup_arch(char ** cmdline_p)772 setup_arch(char **cmdline_p)
773 {
774         /*
775          * print what head.S has found out about the machine
776          */
777 #ifndef CONFIG_64BIT
778 	if (MACHINE_IS_VM)
779 		pr_info("Linux is running as a z/VM "
780 			"guest operating system in 31-bit mode\n");
781 	else if (MACHINE_IS_LPAR)
782 		pr_info("Linux is running natively in 31-bit mode\n");
783 	if (MACHINE_HAS_IEEE)
784 		pr_info("The hardware system has IEEE compatible "
785 			"floating point units\n");
786 	else
787 		pr_info("The hardware system has no IEEE compatible "
788 			"floating point units\n");
789 #else /* CONFIG_64BIT */
790 	if (MACHINE_IS_VM)
791 		pr_info("Linux is running as a z/VM "
792 			"guest operating system in 64-bit mode\n");
793 	else if (MACHINE_IS_KVM)
794 		pr_info("Linux is running under KVM in 64-bit mode\n");
795 	else if (MACHINE_IS_LPAR)
796 		pr_info("Linux is running natively in 64-bit mode\n");
797 #endif /* CONFIG_64BIT */
798 
799 	/* Have one command line that is parsed and saved in /proc/cmdline */
800 	/* boot_command_line has been already set up in early.c */
801 	*cmdline_p = boot_command_line;
802 
803         ROOT_DEV = Root_RAM0;
804 
805 	init_mm.start_code = PAGE_OFFSET;
806 	init_mm.end_code = (unsigned long) &_etext;
807 	init_mm.end_data = (unsigned long) &_edata;
808 	init_mm.brk = (unsigned long) &_end;
809 
810 	if (MACHINE_HAS_MVCOS)
811 		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
812 	else
813 		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
814 
815 	parse_early_param();
816 
817 	setup_ipl();
818 	setup_memory_end();
819 	setup_addressing_mode();
820 	setup_memory();
821 	setup_resources();
822 	setup_lowcore();
823 
824         cpu_init();
825 	s390_init_cpu_topology();
826 
827 	/*
828 	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
829 	 */
830 	setup_hwcaps();
831 
832 	/*
833 	 * Create kernel page tables and switch to virtual addressing.
834 	 */
835         paging_init();
836 
837         /* Setup default console */
838 	conmode_default();
839 	set_preferred_console();
840 
841 	/* Setup zfcpdump support */
842 	setup_zfcpdump(console_devno);
843 }
844