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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *    Copyright IBM Corp. 2007, 2009
  4 *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
  5 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
  6 */
  7
  8#define KMSG_COMPONENT "setup"
  9#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 10
 11#include <linux/compiler.h>
 12#include <linux/init.h>
 13#include <linux/errno.h>
 14#include <linux/string.h>
 15#include <linux/ctype.h>
 16#include <linux/lockdep.h>
 17#include <linux/extable.h>
 18#include <linux/pfn.h>
 19#include <linux/uaccess.h>
 20#include <linux/kernel.h>
 
 
 
 21#include <asm/diag.h>
 22#include <asm/ebcdic.h>
 
 23#include <asm/ipl.h>
 24#include <asm/lowcore.h>
 25#include <asm/processor.h>
 26#include <asm/sections.h>
 27#include <asm/setup.h>
 28#include <asm/sysinfo.h>
 29#include <asm/cpcmd.h>
 30#include <asm/sclp.h>
 31#include <asm/facility.h>
 32#include <asm/boot_data.h>
 33#include "entry.h"
 34
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 35static void __init reset_tod_clock(void)
 36{
 37	u64 time;
 38
 39	if (store_tod_clock(&time) == 0)
 40		return;
 41	/* TOD clock not running. Set the clock to Unix Epoch. */
 42	if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
 43		disabled_wait();
 44
 45	memset(tod_clock_base, 0, 16);
 46	*(__u64 *) &tod_clock_base[1] = TOD_UNIX_EPOCH;
 47	S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
 48}
 49
 50/*
 51 * Initialize storage key for kernel pages
 52 */
 53static noinline __init void init_kernel_storage_key(void)
 54{
 55#if PAGE_DEFAULT_KEY
 56	unsigned long end_pfn, init_pfn;
 57
 58	end_pfn = PFN_UP(__pa(_end));
 59
 60	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 61		page_set_storage_key(init_pfn << PAGE_SHIFT,
 62				     PAGE_DEFAULT_KEY, 0);
 63#endif
 64}
 65
 66static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
 67
 68static noinline __init void detect_machine_type(void)
 69{
 70	struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
 71
 72	/* Check current-configuration-level */
 73	if (stsi(NULL, 0, 0, 0) <= 2) {
 74		S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
 75		return;
 76	}
 77	/* Get virtual-machine cpu information. */
 78	if (stsi(vmms, 3, 2, 2) || !vmms->count)
 79		return;
 80
 81	/* Detect known hypervisors */
 82	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
 83		S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
 84	else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4))
 85		S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 86}
 87
 88/* Remove leading, trailing and double whitespace. */
 89static inline void strim_all(char *str)
 90{
 91	char *s;
 92
 93	s = strim(str);
 94	if (s != str)
 95		memmove(str, s, strlen(s));
 96	while (*str) {
 97		if (!isspace(*str++))
 98			continue;
 99		if (isspace(*str)) {
100			s = skip_spaces(str);
101			memmove(str, s, strlen(s) + 1);
102		}
103	}
104}
105
106static noinline __init void setup_arch_string(void)
107{
108	struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
109	struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page;
110	char mstr[80], hvstr[17];
111
112	if (stsi(mach, 1, 1, 1))
113		return;
114	EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
115	EBCASC(mach->type, sizeof(mach->type));
116	EBCASC(mach->model, sizeof(mach->model));
117	EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
118	sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s",
119		mach->manufacturer, mach->type,
120		mach->model, mach->model_capacity);
121	strim_all(mstr);
122	if (stsi(vm, 3, 2, 2) == 0 && vm->count) {
123		EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi));
124		sprintf(hvstr, "%-16.16s", vm->vm[0].cpi);
125		strim_all(hvstr);
126	} else {
127		sprintf(hvstr, "%s",
128			MACHINE_IS_LPAR ? "LPAR" :
129			MACHINE_IS_VM ? "z/VM" :
130			MACHINE_IS_KVM ? "KVM" : "unknown");
131	}
132	dump_stack_set_arch_desc("%s (%s)", mstr, hvstr);
133}
134
135static __init void setup_topology(void)
136{
137	int max_mnest;
138
139	if (!test_facility(11))
140		return;
141	S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
142	for (max_mnest = 6; max_mnest > 1; max_mnest--) {
143		if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
144			break;
145	}
146	topology_max_mnest = max_mnest;
147}
148
149static void early_pgm_check_handler(void)
150{
151	const struct exception_table_entry *fixup;
152	unsigned long cr0, cr0_new;
153	unsigned long addr;
154
155	addr = S390_lowcore.program_old_psw.addr;
156	fixup = s390_search_extables(addr);
157	if (!fixup)
158		disabled_wait();
159	/* Disable low address protection before storing into lowcore. */
160	__ctl_store(cr0, 0, 0);
161	cr0_new = cr0 & ~(1UL << 28);
162	__ctl_load(cr0_new, 0, 0);
163	S390_lowcore.program_old_psw.addr = extable_fixup(fixup);
164	__ctl_load(cr0, 0, 0);
165}
166
167static noinline __init void setup_lowcore_early(void)
168{
169	psw_t psw;
170
171	psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
172	psw.addr = (unsigned long) s390_base_ext_handler;
173	S390_lowcore.external_new_psw = psw;
174	psw.addr = (unsigned long) s390_base_pgm_handler;
175	S390_lowcore.program_new_psw = psw;
176	s390_base_pgm_handler_fn = early_pgm_check_handler;
177	S390_lowcore.preempt_count = INIT_PREEMPT_COUNT;
178}
179
180static noinline __init void setup_facility_list(void)
181{
182	memcpy(S390_lowcore.alt_stfle_fac_list,
183	       S390_lowcore.stfle_fac_list,
184	       sizeof(S390_lowcore.alt_stfle_fac_list));
185	if (!IS_ENABLED(CONFIG_KERNEL_NOBP))
186		__clear_facility(82, S390_lowcore.alt_stfle_fac_list);
187}
188
189static __init void detect_diag9c(void)
190{
191	unsigned int cpu_address;
192	int rc;
193
194	cpu_address = stap();
195	diag_stat_inc(DIAG_STAT_X09C);
196	asm volatile(
197		"	diag	%2,0,0x9c\n"
198		"0:	la	%0,0\n"
199		"1:\n"
200		EX_TABLE(0b,1b)
201		: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
202	if (!rc)
203		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
204}
205
206static __init void detect_diag44(void)
207{
208	int rc;
209
210	diag_stat_inc(DIAG_STAT_X044);
211	asm volatile(
212		"	diag	0,0,0x44\n"
213		"0:	la	%0,0\n"
214		"1:\n"
215		EX_TABLE(0b,1b)
216		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
217	if (!rc)
218		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
219}
220
221static __init void detect_machine_facilities(void)
222{
223	if (test_facility(8)) {
224		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
225		__ctl_set_bit(0, 23);
226	}
227	if (test_facility(78))
228		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
229	if (test_facility(3))
230		S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
231	if (test_facility(50) && test_facility(73)) {
232		S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
233		__ctl_set_bit(0, 55);
234	}
235	if (test_facility(51))
236		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
237	if (test_facility(129)) {
238		S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
239		__ctl_set_bit(0, 17);
240	}
241	if (test_facility(130)) {
242		S390_lowcore.machine_flags |= MACHINE_FLAG_NX;
243		__ctl_set_bit(0, 20);
244	}
245	if (test_facility(133))
246		S390_lowcore.machine_flags |= MACHINE_FLAG_GS;
247	if (test_facility(139) && (tod_clock_base[1] & 0x80)) {
248		/* Enabled signed clock comparator comparisons */
249		S390_lowcore.machine_flags |= MACHINE_FLAG_SCC;
250		clock_comparator_max = -1ULL >> 1;
251		__ctl_set_bit(0, 53);
252	}
 
 
 
 
 
 
253}
254
255static inline void save_vector_registers(void)
256{
257#ifdef CONFIG_CRASH_DUMP
258	if (test_facility(129))
259		save_vx_regs(boot_cpu_vector_save_area);
260#endif
261}
262
263static int __init disable_vector_extension(char *str)
264{
265	S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX;
266	__ctl_clear_bit(0, 17);
267	return 0;
268}
269early_param("novx", disable_vector_extension);
270
271static int __init noexec_setup(char *str)
272{
273	bool enabled;
274	int rc;
275
276	rc = kstrtobool(str, &enabled);
277	if (!rc && !enabled) {
278		/* Disable no-execute support */
279		S390_lowcore.machine_flags &= ~MACHINE_FLAG_NX;
280		__ctl_clear_bit(0, 20);
281	}
282	return rc;
283}
284early_param("noexec", noexec_setup);
285
286static int __init cad_setup(char *str)
287{
288	bool enabled;
289	int rc;
290
291	rc = kstrtobool(str, &enabled);
292	if (!rc && enabled && test_facility(128))
293		/* Enable problem state CAD. */
294		__ctl_set_bit(2, 3);
295	return rc;
296}
297early_param("cad", cad_setup);
298
299char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
300static void __init setup_boot_command_line(void)
301{
302	/* copy arch command line */
303	strlcpy(boot_command_line, early_command_line, ARCH_COMMAND_LINE_SIZE);
304}
305
306static void __init check_image_bootable(void)
307{
308	if (!memcmp(EP_STRING, (void *)EP_OFFSET, strlen(EP_STRING)))
309		return;
310
311	sclp_early_printk("Linux kernel boot failure: An attempt to boot a vmlinux ELF image failed.\n");
312	sclp_early_printk("This image does not contain all parts necessary for starting up. Use\n");
313	sclp_early_printk("bzImage or arch/s390/boot/compressed/vmlinux instead.\n");
314	disabled_wait();
315}
316
317void __init startup_init(void)
318{
 
319	reset_tod_clock();
320	check_image_bootable();
321	time_early_init();
322	init_kernel_storage_key();
323	lockdep_off();
 
324	setup_lowcore_early();
325	setup_facility_list();
326	detect_machine_type();
327	setup_arch_string();
328	setup_boot_command_line();
329	detect_diag9c();
330	detect_diag44();
331	detect_machine_facilities();
332	save_vector_registers();
333	setup_topology();
334	sclp_early_detect();
 
 
335	lockdep_on();
336}
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *    Copyright IBM Corp. 2007, 2009
  4 *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
 
  5 */
  6
  7#define KMSG_COMPONENT "setup"
  8#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  9
 10#include <linux/compiler.h>
 11#include <linux/init.h>
 12#include <linux/errno.h>
 13#include <linux/string.h>
 14#include <linux/ctype.h>
 15#include <linux/lockdep.h>
 16#include <linux/extable.h>
 17#include <linux/pfn.h>
 18#include <linux/uaccess.h>
 19#include <linux/kernel.h>
 20#include <asm/asm-extable.h>
 21#include <linux/memblock.h>
 22#include <asm/access-regs.h>
 23#include <asm/diag.h>
 24#include <asm/ebcdic.h>
 25#include <asm/fpu.h>
 26#include <asm/ipl.h>
 27#include <asm/lowcore.h>
 28#include <asm/processor.h>
 29#include <asm/sections.h>
 30#include <asm/setup.h>
 31#include <asm/sysinfo.h>
 32#include <asm/cpcmd.h>
 33#include <asm/sclp.h>
 34#include <asm/facility.h>
 35#include <asm/boot_data.h>
 36#include "entry.h"
 37
 38#define decompressor_handled_param(param)			\
 39static int __init ignore_decompressor_param_##param(char *s)	\
 40{								\
 41	return 0;						\
 42}								\
 43early_param(#param, ignore_decompressor_param_##param)
 44
 45decompressor_handled_param(mem);
 46decompressor_handled_param(vmalloc);
 47decompressor_handled_param(dfltcc);
 48decompressor_handled_param(facilities);
 49decompressor_handled_param(nokaslr);
 50decompressor_handled_param(cmma);
 51#if IS_ENABLED(CONFIG_KVM)
 52decompressor_handled_param(prot_virt);
 53#endif
 54
 55static void __init kasan_early_init(void)
 56{
 57#ifdef CONFIG_KASAN
 58	init_task.kasan_depth = 0;
 59	sclp_early_printk("KernelAddressSanitizer initialized\n");
 60#endif
 61}
 62
 63static void __init reset_tod_clock(void)
 64{
 65	union tod_clock clk;
 66
 67	if (store_tod_clock_ext_cc(&clk) == 0)
 68		return;
 69	/* TOD clock not running. Set the clock to Unix Epoch. */
 70	if (set_tod_clock(TOD_UNIX_EPOCH) || store_tod_clock_ext_cc(&clk))
 71		disabled_wait();
 72
 73	memset(&tod_clock_base, 0, sizeof(tod_clock_base));
 74	tod_clock_base.tod = TOD_UNIX_EPOCH;
 75	S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
 76}
 77
 78/*
 79 * Initialize storage key for kernel pages
 80 */
 81static noinline __init void init_kernel_storage_key(void)
 82{
 83#if PAGE_DEFAULT_KEY
 84	unsigned long end_pfn, init_pfn;
 85
 86	end_pfn = PFN_UP(__pa(_end));
 87
 88	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 89		page_set_storage_key(init_pfn << PAGE_SHIFT,
 90				     PAGE_DEFAULT_KEY, 0);
 91#endif
 92}
 93
 94static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
 95
 96static noinline __init void detect_machine_type(void)
 97{
 98	struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
 99
100	/* Check current-configuration-level */
101	if (stsi(NULL, 0, 0, 0) <= 2) {
102		S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
103		return;
104	}
105	/* Get virtual-machine cpu information. */
106	if (stsi(vmms, 3, 2, 2) || !vmms->count)
107		return;
108
109	/* Detect known hypervisors */
110	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
111		S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
112	else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4))
113		S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
114}
115
116/* Remove leading, trailing and double whitespace. */
117static inline void strim_all(char *str)
118{
119	char *s;
120
121	s = strim(str);
122	if (s != str)
123		memmove(str, s, strlen(s));
124	while (*str) {
125		if (!isspace(*str++))
126			continue;
127		if (isspace(*str)) {
128			s = skip_spaces(str);
129			memmove(str, s, strlen(s) + 1);
130		}
131	}
132}
133
134static noinline __init void setup_arch_string(void)
135{
136	struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
137	struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page;
138	char mstr[80], hvstr[17];
139
140	if (stsi(mach, 1, 1, 1))
141		return;
142	EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
143	EBCASC(mach->type, sizeof(mach->type));
144	EBCASC(mach->model, sizeof(mach->model));
145	EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
146	sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s",
147		mach->manufacturer, mach->type,
148		mach->model, mach->model_capacity);
149	strim_all(mstr);
150	if (stsi(vm, 3, 2, 2) == 0 && vm->count) {
151		EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi));
152		sprintf(hvstr, "%-16.16s", vm->vm[0].cpi);
153		strim_all(hvstr);
154	} else {
155		sprintf(hvstr, "%s",
156			MACHINE_IS_LPAR ? "LPAR" :
157			MACHINE_IS_VM ? "z/VM" :
158			MACHINE_IS_KVM ? "KVM" : "unknown");
159	}
160	dump_stack_set_arch_desc("%s (%s)", mstr, hvstr);
161}
162
163static __init void setup_topology(void)
164{
165	int max_mnest;
166
167	if (!test_facility(11))
168		return;
169	S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
170	for (max_mnest = 6; max_mnest > 1; max_mnest--) {
171		if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
172			break;
173	}
174	topology_max_mnest = max_mnest;
175}
176
177void __do_early_pgm_check(struct pt_regs *regs)
178{
179	if (!fixup_exception(regs))
 
 
 
 
 
 
180		disabled_wait();
 
 
 
 
 
 
181}
182
183static noinline __init void setup_lowcore_early(void)
184{
185	psw_t psw;
186
187	psw.addr = (unsigned long)early_pgm_check_handler;
188	psw.mask = PSW_KERNEL_BITS;
 
 
189	S390_lowcore.program_new_psw = psw;
 
190	S390_lowcore.preempt_count = INIT_PREEMPT_COUNT;
191}
192
193static noinline __init void setup_facility_list(void)
194{
195	memcpy(alt_stfle_fac_list, stfle_fac_list, sizeof(alt_stfle_fac_list));
 
 
196	if (!IS_ENABLED(CONFIG_KERNEL_NOBP))
197		__clear_facility(82, alt_stfle_fac_list);
198}
199
200static __init void detect_diag9c(void)
201{
202	unsigned int cpu_address;
203	int rc;
204
205	cpu_address = stap();
206	diag_stat_inc(DIAG_STAT_X09C);
207	asm volatile(
208		"	diag	%2,0,0x9c\n"
209		"0:	la	%0,0\n"
210		"1:\n"
211		EX_TABLE(0b,1b)
212		: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
213	if (!rc)
214		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
215}
216
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
217static __init void detect_machine_facilities(void)
218{
219	if (test_facility(8)) {
220		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
221		system_ctl_set_bit(0, CR0_EDAT_BIT);
222	}
223	if (test_facility(78))
224		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
225	if (test_facility(3))
226		S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
227	if (test_facility(50) && test_facility(73)) {
228		S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
229		system_ctl_set_bit(0, CR0_TRANSACTIONAL_EXECUTION_BIT);
230	}
231	if (test_facility(51))
232		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
233	if (test_facility(129))
234		system_ctl_set_bit(0, CR0_VECTOR_BIT);
235	if (test_facility(130))
 
 
236		S390_lowcore.machine_flags |= MACHINE_FLAG_NX;
 
 
237	if (test_facility(133))
238		S390_lowcore.machine_flags |= MACHINE_FLAG_GS;
239	if (test_facility(139) && (tod_clock_base.tod >> 63)) {
240		/* Enabled signed clock comparator comparisons */
241		S390_lowcore.machine_flags |= MACHINE_FLAG_SCC;
242		clock_comparator_max = -1ULL >> 1;
243		system_ctl_set_bit(0, CR0_CLOCK_COMPARATOR_SIGN_BIT);
244	}
245	if (IS_ENABLED(CONFIG_PCI) && test_facility(153)) {
246		S390_lowcore.machine_flags |= MACHINE_FLAG_PCI_MIO;
247		/* the control bit is set during PCI initialization */
248	}
249	if (test_facility(194))
250		S390_lowcore.machine_flags |= MACHINE_FLAG_RDP;
251}
252
253static inline void save_vector_registers(void)
254{
255#ifdef CONFIG_CRASH_DUMP
256	if (test_facility(129))
257		save_vx_regs(boot_cpu_vector_save_area);
258#endif
259}
260
261static inline void setup_low_address_protection(void)
 
 
 
 
 
 
 
 
262{
263	system_ctl_set_bit(0, CR0_LOW_ADDRESS_PROTECTION_BIT);
 
 
 
 
 
 
 
 
 
264}
 
265
266static inline void setup_access_registers(void)
267{
268	unsigned int acrs[NUM_ACRS] = { 0 };
 
269
270	restore_access_regs(acrs);
 
 
 
 
271}
 
272
273char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
274static void __init setup_boot_command_line(void)
275{
276	/* copy arch command line */
277	strscpy(boot_command_line, early_command_line, COMMAND_LINE_SIZE);
278}
279
280static void __init sort_amode31_extable(void)
281{
282	sort_extable(__start_amode31_ex_table, __stop_amode31_ex_table);
 
 
 
 
 
 
283}
284
285void __init startup_init(void)
286{
287	kasan_early_init();
288	reset_tod_clock();
 
289	time_early_init();
290	init_kernel_storage_key();
291	lockdep_off();
292	sort_amode31_extable();
293	setup_lowcore_early();
294	setup_facility_list();
295	detect_machine_type();
296	setup_arch_string();
297	setup_boot_command_line();
298	detect_diag9c();
 
299	detect_machine_facilities();
300	save_vector_registers();
301	setup_topology();
302	sclp_early_detect();
303	setup_low_address_protection();
304	setup_access_registers();
305	lockdep_on();
306}