summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/early.c
blob: 2871e98fdd0ba94fd97330e748e2264bbd2cd3b7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
// SPDX-License-Identifier: GPL-2.0
/*
 *    Copyright IBM Corp. 2007, 2009
 *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
 */

#define KMSG_COMPONENT "setup"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/lockdep.h>
#include <linux/extable.h>
#include <linux/pfn.h>
#include <linux/uaccess.h>
#include <linux/kernel.h>
#include <asm/diag.h>
#include <asm/ebcdic.h>
#include <asm/ipl.h>
#include <asm/lowcore.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sysinfo.h>
#include <asm/cpcmd.h>
#include <asm/sclp.h>
#include <asm/facility.h>
#include <asm/boot_data.h>
#include "entry.h"

/*
 * Initialize storage key for kernel pages
 */
static noinline __init void init_kernel_storage_key(void)
{
#if PAGE_DEFAULT_KEY
	unsigned long end_pfn, init_pfn;

	end_pfn = PFN_UP(__pa(_end));

	for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
		page_set_storage_key(init_pfn << PAGE_SHIFT,
				     PAGE_DEFAULT_KEY, 0);
#endif
}

static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);

static noinline __init void detect_machine_type(void)
{
	struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;

	/* Check current-configuration-level */
	if (stsi(NULL, 0, 0, 0) <= 2) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
		return;
	}
	/* Get virtual-machine cpu information. */
	if (stsi(vmms, 3, 2, 2) || !vmms->count)
		return;

	/* Running under KVM? If not we assume z/VM */
	if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
		S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
	else
		S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
}

/* Remove leading, trailing and double whitespace. */
static inline void strim_all(char *str)
{
	char *s;

	s = strim(str);
	if (s != str)
		memmove(str, s, strlen(s));
	while (*str) {
		if (!isspace(*str++))
			continue;
		if (isspace(*str)) {
			s = skip_spaces(str);
			memmove(str, s, strlen(s) + 1);
		}
	}
}

static noinline __init void setup_arch_string(void)
{
	struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
	struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page;
	char mstr[80], hvstr[17];

	if (stsi(mach, 1, 1, 1))
		return;
	EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
	EBCASC(mach->type, sizeof(mach->type));
	EBCASC(mach->model, sizeof(mach->model));
	EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
	sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s",
		mach->manufacturer, mach->type,
		mach->model, mach->model_capacity);
	strim_all(mstr);
	if (stsi(vm, 3, 2, 2) == 0 && vm->count) {
		EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi));
		sprintf(hvstr, "%-16.16s", vm->vm[0].cpi);
		strim_all(hvstr);
	} else {
		sprintf(hvstr, "%s",
			MACHINE_IS_LPAR ? "LPAR" :
			MACHINE_IS_VM ? "z/VM" :
			MACHINE_IS_KVM ? "KVM" : "unknown");
	}
	dump_stack_set_arch_desc("%s (%s)", mstr, hvstr);
}

static __init void setup_topology(void)
{
	int max_mnest;

	if (!test_facility(11))
		return;
	S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
	for (max_mnest = 6; max_mnest > 1; max_mnest--) {
		if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
			break;
	}
	topology_max_mnest = max_mnest;
}

static void early_pgm_check_handler(void)
{
	const struct exception_table_entry *fixup;
	unsigned long cr0, cr0_new;
	unsigned long addr;

	addr = S390_lowcore.program_old_psw.addr;
	fixup = search_exception_tables(addr);
	if (!fixup)
		disabled_wait(0);
	/* Disable low address protection before storing into lowcore. */
	__ctl_store(cr0, 0, 0);
	cr0_new = cr0 & ~(1UL << 28);
	__ctl_load(cr0_new, 0, 0);
	S390_lowcore.program_old_psw.addr = extable_fixup(fixup);
	__ctl_load(cr0, 0, 0);
}

static noinline __init void setup_lowcore_early(void)
{
	psw_t psw;

	psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
	psw.addr = (unsigned long) s390_base_ext_handler;
	S390_lowcore.external_new_psw = psw;
	psw.addr = (unsigned long) s390_base_pgm_handler;
	S390_lowcore.program_new_psw = psw;
	s390_base_pgm_handler_fn = early_pgm_check_handler;
	S390_lowcore.preempt_count = INIT_PREEMPT_COUNT;
}

static noinline __init void setup_facility_list(void)
{
	memcpy(S390_lowcore.alt_stfle_fac_list,
	       S390_lowcore.stfle_fac_list,
	       sizeof(S390_lowcore.alt_stfle_fac_list));
	if (!IS_ENABLED(CONFIG_KERNEL_NOBP))
		__clear_facility(82, S390_lowcore.alt_stfle_fac_list);
}

static __init void detect_diag9c(void)
{
	unsigned int cpu_address;
	int rc;

	cpu_address = stap();
	diag_stat_inc(DIAG_STAT_X09C);
	asm volatile(
		"	diag	%2,0,0x9c\n"
		"0:	la	%0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
	if (!rc)
		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
}

static __init void detect_diag44(void)
{
	int rc;

	diag_stat_inc(DIAG_STAT_X044);
	asm volatile(
		"	diag	0,0,0x44\n"
		"0:	la	%0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
	if (!rc)
		S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
}

static __init void detect_machine_facilities(void)
{
	if (test_facility(8)) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
		__ctl_set_bit(0, 23);
	}
	if (test_facility(78))
		S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
	if (test_facility(3))
		S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
	if (test_facility(50) && test_facility(73)) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
		__ctl_set_bit(0, 55);
	}
	if (test_facility(51))
		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
	if (test_facility(129)) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
		__ctl_set_bit(0, 17);
	}
	if (test_facility(130)) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_NX;
		__ctl_set_bit(0, 20);
	}
	if (test_facility(133))
		S390_lowcore.machine_flags |= MACHINE_FLAG_GS;
	if (test_facility(139) && (tod_clock_base[1] & 0x80)) {
		/* Enabled signed clock comparator comparisons */
		S390_lowcore.machine_flags |= MACHINE_FLAG_SCC;
		clock_comparator_max = -1ULL >> 1;
		__ctl_set_bit(0, 53);
	}
}

static inline void save_vector_registers(void)
{
#ifdef CONFIG_CRASH_DUMP
	if (test_facility(129))
		save_vx_regs(boot_cpu_vector_save_area);
#endif
}

static int __init disable_vector_extension(char *str)
{
	S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX;
	__ctl_clear_bit(0, 17);
	return 0;
}
early_param("novx", disable_vector_extension);

static int __init noexec_setup(char *str)
{
	bool enabled;
	int rc;

	rc = kstrtobool(str, &enabled);
	if (!rc && !enabled) {
		/* Disable no-execute support */
		S390_lowcore.machine_flags &= ~MACHINE_FLAG_NX;
		__ctl_clear_bit(0, 20);
	}
	return rc;
}
early_param("noexec", noexec_setup);

static int __init cad_setup(char *str)
{
	bool enabled;
	int rc;

	rc = kstrtobool(str, &enabled);
	if (!rc && enabled && test_facility(128))
		/* Enable problem state CAD. */
		__ctl_set_bit(2, 3);
	return rc;
}
early_param("cad", cad_setup);

char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
static void __init setup_boot_command_line(void)
{
	/* copy arch command line */
	strlcpy(boot_command_line, early_command_line, ARCH_COMMAND_LINE_SIZE);
}

static void __init check_image_bootable(void)
{
	if (!memcmp(EP_STRING, (void *)EP_OFFSET, strlen(EP_STRING)))
		return;

	sclp_early_printk("Linux kernel boot failure: An attempt to boot a vmlinux ELF image failed.\n");
	sclp_early_printk("This image does not contain all parts necessary for starting up. Use\n");
	sclp_early_printk("bzImage or arch/s390/boot/compressed/vmlinux instead.\n");
	disabled_wait(0xbadb007);
}

void __init startup_init(void)
{
	check_image_bootable();
	time_early_init();
	init_kernel_storage_key();
	lockdep_off();
	setup_lowcore_early();
	setup_facility_list();
	detect_machine_type();
	setup_arch_string();
	ipl_store_parameters();
	setup_boot_command_line();
	detect_diag9c();
	detect_diag44();
	detect_machine_facilities();
	save_vector_registers();
	setup_topology();
	sclp_early_detect();
	lockdep_on();
}