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/random.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/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/facility.h>
51#include <asm/smp.h>
52#include <asm/mmu_context.h>
53#include <asm/cpcmd.h>
54#include <asm/lowcore.h>
55#include <asm/irq.h>
56#include <asm/page.h>
57#include <asm/ptrace.h>
58#include <asm/sections.h>
59#include <asm/ebcdic.h>
60#include <asm/kvm_virtio.h>
61#include <asm/diag.h>
62#include <asm/os_info.h>
63#include <asm/sclp.h>
64#include <asm/sysinfo.h>
65#include "entry.h"
66
67/*
68 * Machine setup..
69 */
70unsigned int console_mode = 0;
71EXPORT_SYMBOL(console_mode);
72
73unsigned int console_devno = -1;
74EXPORT_SYMBOL(console_devno);
75
76unsigned int console_irq = -1;
77EXPORT_SYMBOL(console_irq);
78
79unsigned long elf_hwcap = 0;
80char elf_platform[ELF_PLATFORM_SIZE];
81
82int __initdata memory_end_set;
83unsigned long __initdata memory_end;
84unsigned long __initdata max_physmem_end;
85
86unsigned long VMALLOC_START;
87EXPORT_SYMBOL(VMALLOC_START);
88
89unsigned long VMALLOC_END;
90EXPORT_SYMBOL(VMALLOC_END);
91
92struct page *vmemmap;
93EXPORT_SYMBOL(vmemmap);
94
95unsigned long MODULES_VADDR;
96unsigned long MODULES_END;
97
98/* An array with a pointer to the lowcore of every CPU. */
99struct _lowcore *lowcore_ptr[NR_CPUS];
100EXPORT_SYMBOL(lowcore_ptr);
101
102/*
103 * This is set up by the setup-routine at boot-time
104 * for S390 need to find out, what we have to setup
105 * using address 0x10400 ...
106 */
107
108#include <asm/setup.h>
109
110/*
111 * condev= and conmode= setup parameter.
112 */
113
114static int __init condev_setup(char *str)
115{
116	int vdev;
117
118	vdev = simple_strtoul(str, &str, 0);
119	if (vdev >= 0 && vdev < 65536) {
120		console_devno = vdev;
121		console_irq = -1;
122	}
123	return 1;
124}
125
126__setup("condev=", condev_setup);
127
128static void __init set_preferred_console(void)
129{
130	if (MACHINE_IS_KVM) {
131		if (sclp_has_vt220())
132			add_preferred_console("ttyS", 1, NULL);
133		else if (sclp_has_linemode())
134			add_preferred_console("ttyS", 0, NULL);
135		else
136			add_preferred_console("hvc", 0, NULL);
137	} else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
138		add_preferred_console("ttyS", 0, NULL);
139	else if (CONSOLE_IS_3270)
140		add_preferred_console("tty3270", 0, NULL);
141}
142
143static int __init conmode_setup(char *str)
144{
145#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
146	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
147                SET_CONSOLE_SCLP;
148#endif
149#if defined(CONFIG_TN3215_CONSOLE)
150	if (strncmp(str, "3215", 5) == 0)
151		SET_CONSOLE_3215;
152#endif
153#if defined(CONFIG_TN3270_CONSOLE)
154	if (strncmp(str, "3270", 5) == 0)
155		SET_CONSOLE_3270;
156#endif
157	set_preferred_console();
158        return 1;
159}
160
161__setup("conmode=", conmode_setup);
162
163static void __init conmode_default(void)
164{
165	char query_buffer[1024];
166	char *ptr;
167
168        if (MACHINE_IS_VM) {
169		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
170		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
171		ptr = strstr(query_buffer, "SUBCHANNEL =");
172		console_irq = simple_strtoul(ptr + 13, NULL, 16);
173		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
174		ptr = strstr(query_buffer, "CONMODE");
175		/*
176		 * Set the conmode to 3215 so that the device recognition
177		 * will set the cu_type of the console to 3215. If the
178		 * conmode is 3270 and we don't set it back then both
179		 * 3215 and the 3270 driver will try to access the console
180		 * device (3215 as console and 3270 as normal tty).
181		 */
182		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
183		if (ptr == NULL) {
184#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
185			SET_CONSOLE_SCLP;
186#endif
187			return;
188		}
189		if (strncmp(ptr + 8, "3270", 4) == 0) {
190#if defined(CONFIG_TN3270_CONSOLE)
191			SET_CONSOLE_3270;
192#elif defined(CONFIG_TN3215_CONSOLE)
193			SET_CONSOLE_3215;
194#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
195			SET_CONSOLE_SCLP;
196#endif
197		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
198#if defined(CONFIG_TN3215_CONSOLE)
199			SET_CONSOLE_3215;
200#elif defined(CONFIG_TN3270_CONSOLE)
201			SET_CONSOLE_3270;
202#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
203			SET_CONSOLE_SCLP;
204#endif
205		}
206	} else {
207#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208		SET_CONSOLE_SCLP;
209#endif
210	}
211}
212
213#ifdef CONFIG_CRASH_DUMP
214static void __init setup_zfcpdump(void)
215{
216	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
217		return;
218	if (OLDMEM_BASE)
219		return;
220	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
221	console_loglevel = 2;
222}
223#else
224static inline void setup_zfcpdump(void) {}
225#endif /* CONFIG_CRASH_DUMP */
226
227 /*
228 * Reboot, halt and power_off stubs. They just call _machine_restart,
229 * _machine_halt or _machine_power_off.
230 */
231
232void machine_restart(char *command)
233{
234	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
235		/*
236		 * Only unblank the console if we are called in enabled
237		 * context or a bust_spinlocks cleared the way for us.
238		 */
239		console_unblank();
240	_machine_restart(command);
241}
242
243void machine_halt(void)
244{
245	if (!in_interrupt() || oops_in_progress)
246		/*
247		 * Only unblank the console if we are called in enabled
248		 * context or a bust_spinlocks cleared the way for us.
249		 */
250		console_unblank();
251	_machine_halt();
252}
253
254void machine_power_off(void)
255{
256	if (!in_interrupt() || oops_in_progress)
257		/*
258		 * Only unblank the console if we are called in enabled
259		 * context or a bust_spinlocks cleared the way for us.
260		 */
261		console_unblank();
262	_machine_power_off();
263}
264
265/*
266 * Dummy power off function.
267 */
268void (*pm_power_off)(void) = machine_power_off;
269EXPORT_SYMBOL_GPL(pm_power_off);
270
271static int __init early_parse_mem(char *p)
272{
273	memory_end = memparse(p, &p);
274	memory_end &= PAGE_MASK;
275	memory_end_set = 1;
276	return 0;
277}
278early_param("mem", early_parse_mem);
279
280static int __init parse_vmalloc(char *arg)
281{
282	if (!arg)
283		return -EINVAL;
284	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
285	return 0;
286}
287early_param("vmalloc", parse_vmalloc);
288
289void *restart_stack __attribute__((__section__(".data")));
290
291static void __init setup_lowcore(void)
292{
293	struct _lowcore *lc;
294
295	/*
296	 * Setup lowcore for boot cpu
297	 */
298	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
299	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
300	lc->restart_psw.mask = PSW_KERNEL_BITS;
301	lc->restart_psw.addr =
302		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
303	lc->external_new_psw.mask = PSW_KERNEL_BITS |
304		PSW_MASK_DAT | PSW_MASK_MCHECK;
305	lc->external_new_psw.addr =
306		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
307	lc->svc_new_psw.mask = PSW_KERNEL_BITS |
308		PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
309	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
310	lc->program_new_psw.mask = PSW_KERNEL_BITS |
311		PSW_MASK_DAT | PSW_MASK_MCHECK;
312	lc->program_new_psw.addr =
313		PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
314	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
315	lc->mcck_new_psw.addr =
316		PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
317	lc->io_new_psw.mask = PSW_KERNEL_BITS |
318		PSW_MASK_DAT | PSW_MASK_MCHECK;
319	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
320	lc->clock_comparator = -1ULL;
321	lc->kernel_stack = ((unsigned long) &init_thread_union)
322		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
323	lc->async_stack = (unsigned long)
324		__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0)
325		+ ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
326	lc->panic_stack = (unsigned long)
327		__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0)
328		+ PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
329	lc->current_task = (unsigned long) init_thread_union.thread_info.task;
330	lc->thread_info = (unsigned long) &init_thread_union;
331	lc->machine_flags = S390_lowcore.machine_flags;
332	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
333	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
334	       MAX_FACILITY_BIT/8);
335	if (MACHINE_HAS_VX)
336		lc->vector_save_area_addr =
337			(unsigned long) &lc->vector_save_area;
338	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
339	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
340	lc->async_enter_timer = S390_lowcore.async_enter_timer;
341	lc->exit_timer = S390_lowcore.exit_timer;
342	lc->user_timer = S390_lowcore.user_timer;
343	lc->system_timer = S390_lowcore.system_timer;
344	lc->steal_timer = S390_lowcore.steal_timer;
345	lc->last_update_timer = S390_lowcore.last_update_timer;
346	lc->last_update_clock = S390_lowcore.last_update_clock;
347
348	restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
349	restart_stack += ASYNC_SIZE;
350
351	/*
352	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
353	 * restart data to the absolute zero lowcore. This is necessary if
354	 * PSW restart is done on an offline CPU that has lowcore zero.
355	 */
356	lc->restart_stack = (unsigned long) restart_stack;
357	lc->restart_fn = (unsigned long) do_restart;
358	lc->restart_data = 0;
359	lc->restart_source = -1UL;
360
361	/* Setup absolute zero lowcore */
362	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
363	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
364	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
365	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
366	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
367
368#ifdef CONFIG_SMP
369	lc->spinlock_lockval = arch_spin_lockval(0);
370#endif
371
372	set_prefix((u32)(unsigned long) lc);
373	lowcore_ptr[0] = lc;
374}
375
376static struct resource code_resource = {
377	.name  = "Kernel code",
378	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
379};
380
381static struct resource data_resource = {
382	.name = "Kernel data",
383	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
384};
385
386static struct resource bss_resource = {
387	.name = "Kernel bss",
388	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
389};
390
391static struct resource __initdata *standard_resources[] = {
392	&code_resource,
393	&data_resource,
394	&bss_resource,
395};
396
397static void __init setup_resources(void)
398{
399	struct resource *res, *std_res, *sub_res;
400	struct memblock_region *reg;
401	int j;
402
403	code_resource.start = (unsigned long) &_text;
404	code_resource.end = (unsigned long) &_etext - 1;
405	data_resource.start = (unsigned long) &_etext;
406	data_resource.end = (unsigned long) &_edata - 1;
407	bss_resource.start = (unsigned long) &__bss_start;
408	bss_resource.end = (unsigned long) &__bss_stop - 1;
409
410	for_each_memblock(memory, reg) {
411		res = alloc_bootmem_low(sizeof(*res));
412		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
413
414		res->name = "System RAM";
415		res->start = reg->base;
416		res->end = reg->base + reg->size - 1;
417		request_resource(&iomem_resource, res);
418
419		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
420			std_res = standard_resources[j];
421			if (std_res->start < res->start ||
422			    std_res->start > res->end)
423				continue;
424			if (std_res->end > res->end) {
425				sub_res = alloc_bootmem_low(sizeof(*sub_res));
426				*sub_res = *std_res;
427				sub_res->end = res->end;
428				std_res->start = res->end + 1;
429				request_resource(res, sub_res);
430			} else {
431				request_resource(res, std_res);
432			}
433		}
434	}
435}
436
437static void __init setup_memory_end(void)
438{
439	unsigned long vmax, vmalloc_size, tmp;
440
441	/* Choose kernel address space layout: 2, 3, or 4 levels. */
442	vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
443	tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
444	tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
445	if (tmp + vmalloc_size + MODULES_LEN <= (1UL << 42))
446		vmax = 1UL << 42;	/* 3-level kernel page table */
447	else
448		vmax = 1UL << 53;	/* 4-level kernel page table */
449	/* module area is at the end of the kernel address space. */
450	MODULES_END = vmax;
451	MODULES_VADDR = MODULES_END - MODULES_LEN;
452	VMALLOC_END = MODULES_VADDR;
453	VMALLOC_START = vmax - vmalloc_size;
454
455	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
456	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
457	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
458	tmp = SECTION_ALIGN_UP(tmp);
459	tmp = VMALLOC_START - tmp * sizeof(struct page);
460	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
461	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
462	vmemmap = (struct page *) tmp;
463
464	/* Take care that memory_end is set and <= vmemmap */
465	memory_end = min(memory_end ?: max_physmem_end, tmp);
466	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
467	memblock_remove(memory_end, ULONG_MAX);
468
469	pr_notice("Max memory size: %luMB\n", memory_end >> 20);
470}
471
472static void __init setup_vmcoreinfo(void)
473{
474	mem_assign_absolute(S390_lowcore.vmcore_info, paddr_vmcoreinfo_note());
475}
476
477#ifdef CONFIG_CRASH_DUMP
478
479/*
480 * When kdump is enabled, we have to ensure that no memory from
481 * the area [0 - crashkernel memory size] and
482 * [crashk_res.start - crashk_res.end] is set offline.
483 */
484static int kdump_mem_notifier(struct notifier_block *nb,
485			      unsigned long action, void *data)
486{
487	struct memory_notify *arg = data;
488
489	if (action != MEM_GOING_OFFLINE)
490		return NOTIFY_OK;
491	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
492		return NOTIFY_BAD;
493	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
494		return NOTIFY_OK;
495	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
496		return NOTIFY_OK;
497	return NOTIFY_BAD;
498}
499
500static struct notifier_block kdump_mem_nb = {
501	.notifier_call = kdump_mem_notifier,
502};
503
504#endif
505
506/*
507 * Make sure that the area behind memory_end is protected
508 */
509static void reserve_memory_end(void)
510{
511#ifdef CONFIG_CRASH_DUMP
512	if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
513	    !OLDMEM_BASE && sclp_get_hsa_size()) {
514		memory_end = sclp_get_hsa_size();
515		memory_end &= PAGE_MASK;
516		memory_end_set = 1;
517	}
518#endif
519	if (!memory_end_set)
520		return;
521	memblock_reserve(memory_end, ULONG_MAX);
522}
523
524/*
525 * Make sure that oldmem, where the dump is stored, is protected
526 */
527static void reserve_oldmem(void)
528{
529#ifdef CONFIG_CRASH_DUMP
530	if (OLDMEM_BASE)
531		/* Forget all memory above the running kdump system */
532		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
533#endif
534}
535
536/*
537 * Make sure that oldmem, where the dump is stored, is protected
538 */
539static void remove_oldmem(void)
540{
541#ifdef CONFIG_CRASH_DUMP
542	if (OLDMEM_BASE)
543		/* Forget all memory above the running kdump system */
544		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
545#endif
546}
547
548/*
549 * Reserve memory for kdump kernel to be loaded with kexec
550 */
551static void __init reserve_crashkernel(void)
552{
553#ifdef CONFIG_CRASH_DUMP
554	unsigned long long crash_base, crash_size;
555	phys_addr_t low, high;
556	int rc;
557
558	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
559			       &crash_base);
560
561	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
562	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
563	if (rc || crash_size == 0)
564		return;
565
566	if (memblock.memory.regions[0].size < crash_size) {
567		pr_info("crashkernel reservation failed: %s\n",
568			"first memory chunk must be at least crashkernel size");
569		return;
570	}
571
572	low = crash_base ?: OLDMEM_BASE;
573	high = low + crash_size;
574	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
575		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
576		crash_base = low;
577	} else {
578		/* Find suitable area in free memory */
579		low = max_t(unsigned long, crash_size, sclp_get_hsa_size());
580		high = crash_base ? crash_base + crash_size : ULONG_MAX;
581
582		if (crash_base && crash_base < low) {
583			pr_info("crashkernel reservation failed: %s\n",
584				"crash_base too low");
585			return;
586		}
587		low = crash_base ?: low;
588		crash_base = memblock_find_in_range(low, high, crash_size,
589						    KEXEC_CRASH_MEM_ALIGN);
590	}
591
592	if (!crash_base) {
593		pr_info("crashkernel reservation failed: %s\n",
594			"no suitable area found");
595		return;
596	}
597
598	if (register_memory_notifier(&kdump_mem_nb))
599		return;
600
601	if (!OLDMEM_BASE && MACHINE_IS_VM)
602		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
603	crashk_res.start = crash_base;
604	crashk_res.end = crash_base + crash_size - 1;
605	insert_resource(&iomem_resource, &crashk_res);
606	memblock_remove(crash_base, crash_size);
607	pr_info("Reserving %lluMB of memory at %lluMB "
608		"for crashkernel (System RAM: %luMB)\n",
609		crash_size >> 20, crash_base >> 20,
610		(unsigned long)memblock.memory.total_size >> 20);
611	os_info_crashkernel_add(crash_base, crash_size);
612#endif
613}
614
615/*
616 * Reserve the initrd from being used by memblock
617 */
618static void __init reserve_initrd(void)
619{
620#ifdef CONFIG_BLK_DEV_INITRD
621	initrd_start = INITRD_START;
622	initrd_end = initrd_start + INITRD_SIZE;
623	memblock_reserve(INITRD_START, INITRD_SIZE);
624#endif
625}
626
627/*
628 * Check for initrd being in usable memory
629 */
630static void __init check_initrd(void)
631{
632#ifdef CONFIG_BLK_DEV_INITRD
633	if (INITRD_START && INITRD_SIZE &&
634	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
635		pr_err("initrd does not fit memory.\n");
636		memblock_free(INITRD_START, INITRD_SIZE);
637		initrd_start = initrd_end = 0;
638	}
639#endif
640}
641
642/*
643 * Reserve all kernel text
644 */
645static void __init reserve_kernel(void)
646{
647	unsigned long start_pfn;
648	start_pfn = PFN_UP(__pa(&_end));
649
650	/*
651	 * Reserve memory used for lowcore/command line/kernel image.
652	 */
653	memblock_reserve(0, (unsigned long)_ehead);
654	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
655			 - (unsigned long)_stext);
656}
657
658static void __init reserve_elfcorehdr(void)
659{
660#ifdef CONFIG_CRASH_DUMP
661	if (is_kdump_kernel())
662		memblock_reserve(elfcorehdr_addr - OLDMEM_BASE,
663				 PAGE_ALIGN(elfcorehdr_size));
664#endif
665}
666
667static void __init setup_memory(void)
668{
669	struct memblock_region *reg;
670
671	/*
672	 * Init storage key for present memory
673	 */
674	for_each_memblock(memory, reg) {
675		storage_key_init_range(reg->base, reg->base + reg->size);
676	}
677	psw_set_key(PAGE_DEFAULT_KEY);
678
679	/* Only cosmetics */
680	memblock_enforce_memory_limit(memblock_end_of_DRAM());
681}
682
683/*
684 * Setup hardware capabilities.
685 */
686static int __init setup_hwcaps(void)
687{
688	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
689	struct cpuid cpu_id;
690	int i;
691
692	/*
693	 * The store facility list bits numbers as found in the principles
694	 * of operation are numbered with bit 1UL<<31 as number 0 to
695	 * bit 1UL<<0 as number 31.
696	 *   Bit 0: instructions named N3, "backported" to esa-mode
697	 *   Bit 2: z/Architecture mode is active
698	 *   Bit 7: the store-facility-list-extended facility is installed
699	 *   Bit 17: the message-security assist is installed
700	 *   Bit 19: the long-displacement facility is installed
701	 *   Bit 21: the extended-immediate facility is installed
702	 *   Bit 22: extended-translation facility 3 is installed
703	 *   Bit 30: extended-translation facility 3 enhancement facility
704	 * These get translated to:
705	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
706	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
707	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
708	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
709	 */
710	for (i = 0; i < 6; i++)
711		if (test_facility(stfl_bits[i]))
712			elf_hwcap |= 1UL << i;
713
714	if (test_facility(22) && test_facility(30))
715		elf_hwcap |= HWCAP_S390_ETF3EH;
716
717	/*
718	 * Check for additional facilities with store-facility-list-extended.
719	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
720	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
721	 * as stored by stfl, bits 32-xxx contain additional facilities.
722	 * How many facility words are stored depends on the number of
723	 * doublewords passed to the instruction. The additional facilities
724	 * are:
725	 *   Bit 42: decimal floating point facility is installed
726	 *   Bit 44: perform floating point operation facility is installed
727	 * translated to:
728	 *   HWCAP_S390_DFP bit 6 (42 && 44).
729	 */
730	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
731		elf_hwcap |= HWCAP_S390_DFP;
732
733	/*
734	 * Huge page support HWCAP_S390_HPAGE is bit 7.
735	 */
736	if (MACHINE_HAS_HPAGE)
737		elf_hwcap |= HWCAP_S390_HPAGE;
738
739	/*
740	 * 64-bit register support for 31-bit processes
741	 * HWCAP_S390_HIGH_GPRS is bit 9.
742	 */
743	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
744
745	/*
746	 * Transactional execution support HWCAP_S390_TE is bit 10.
747	 */
748	if (test_facility(50) && test_facility(73))
749		elf_hwcap |= HWCAP_S390_TE;
750
751	/*
752	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
753	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
754	 * instead of facility bit 129.
755	 */
756	if (MACHINE_HAS_VX)
757		elf_hwcap |= HWCAP_S390_VXRS;
758	get_cpu_id(&cpu_id);
759	add_device_randomness(&cpu_id, sizeof(cpu_id));
760	switch (cpu_id.machine) {
761	case 0x9672:
762		strcpy(elf_platform, "g5");
763		break;
764	case 0x2064:
765	case 0x2066:
766	default:	/* Use "z900" as default for 64 bit kernels. */
767		strcpy(elf_platform, "z900");
768		break;
769	case 0x2084:
770	case 0x2086:
771		strcpy(elf_platform, "z990");
772		break;
773	case 0x2094:
774	case 0x2096:
775		strcpy(elf_platform, "z9-109");
776		break;
777	case 0x2097:
778	case 0x2098:
779		strcpy(elf_platform, "z10");
780		break;
781	case 0x2817:
782	case 0x2818:
783		strcpy(elf_platform, "z196");
784		break;
785	case 0x2827:
786	case 0x2828:
787		strcpy(elf_platform, "zEC12");
788		break;
789	case 0x2964:
790		strcpy(elf_platform, "z13");
791		break;
792	}
793	return 0;
794}
795arch_initcall(setup_hwcaps);
796
797/*
798 * Add system information as device randomness
799 */
800static void __init setup_randomness(void)
801{
802	struct sysinfo_3_2_2 *vmms;
803
804	vmms = (struct sysinfo_3_2_2 *) alloc_page(GFP_KERNEL);
805	if (vmms && stsi(vmms, 3, 2, 2) == 0 && vmms->count)
806		add_device_randomness(&vmms, vmms->count);
807	free_page((unsigned long) vmms);
808}
809
810/*
811 * Setup function called from init/main.c just after the banner
812 * was printed.
813 */
814
815void __init setup_arch(char **cmdline_p)
816{
817        /*
818         * print what head.S has found out about the machine
819         */
820	if (MACHINE_IS_VM)
821		pr_info("Linux is running as a z/VM "
822			"guest operating system in 64-bit mode\n");
823	else if (MACHINE_IS_KVM)
824		pr_info("Linux is running under KVM in 64-bit mode\n");
825	else if (MACHINE_IS_LPAR)
826		pr_info("Linux is running natively in 64-bit mode\n");
827
828	/* Have one command line that is parsed and saved in /proc/cmdline */
829	/* boot_command_line has been already set up in early.c */
830	*cmdline_p = boot_command_line;
831
832        ROOT_DEV = Root_RAM0;
833
834	/* Is init_mm really needed? */
835	init_mm.start_code = PAGE_OFFSET;
836	init_mm.end_code = (unsigned long) &_etext;
837	init_mm.end_data = (unsigned long) &_edata;
838	init_mm.brk = (unsigned long) &_end;
839
840	parse_early_param();
841	os_info_init();
842	setup_ipl();
843
844	/* Do some memory reservations *before* memory is added to memblock */
845	reserve_memory_end();
846	reserve_oldmem();
847	reserve_kernel();
848	reserve_initrd();
849	reserve_elfcorehdr();
850	memblock_allow_resize();
851
852	/* Get information about *all* installed memory */
853	detect_memory_memblock();
854
855	remove_oldmem();
856
857	/*
858	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
859	 * extra checks that HOLES_IN_ZONE would require.
860	 *
861	 * Is this still required?
862	 */
863	memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
864
865	setup_memory_end();
866	setup_memory();
867
868	check_initrd();
869	reserve_crashkernel();
870
871	setup_resources();
872	setup_vmcoreinfo();
873	setup_lowcore();
874	smp_fill_possible_mask();
875        cpu_init();
876
877	/*
878	 * Create kernel page tables and switch to virtual addressing.
879	 */
880        paging_init();
881
882        /* Setup default console */
883	conmode_default();
884	set_preferred_console();
885
886	/* Setup zfcpdump support */
887	setup_zfcpdump();
888
889	/* Add system specific data to the random pool */
890	setup_randomness();
891}
892