aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/early.c
blob: 37394b3413e2776dfd24586f0578045e488bd054 (plain) (blame)
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
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
/*
 *  arch/s390/kernel/early.c
 *
 *    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/ftrace.h>
#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/pfn.h>
#include <linux/uaccess.h>
#include <linux/kernel.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 "entry.h"

/*
 * Create a Kernel NSS if the SAVESYS= parameter is defined
 */
#define DEFSYS_CMD_SIZE		128
#define SAVESYS_CMD_SIZE	32

char kernel_nss_name[NSS_NAME_SIZE + 1];

static void __init setup_boot_command_line(void);

/*
 * Get the TOD clock running.
 */
static void __init reset_tod_clock(void)
{
	u64 time;

	if (store_clock(&time) == 0)
		return;
	/* TOD clock not running. Set the clock to Unix Epoch. */
	if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
		disabled_wait(0);

	sched_clock_base_cc = TOD_UNIX_EPOCH;
	S390_lowcore.last_update_clock = sched_clock_base_cc;
}

#ifdef CONFIG_SHARED_KERNEL
int __init savesys_ipl_nss(char *cmd, const int cmdlen);

asm(
	"	.section .init.text,\"ax\",@progbits\n"
	"	.align	4\n"
	"	.type	savesys_ipl_nss, @function\n"
	"savesys_ipl_nss:\n"
#ifdef CONFIG_64BIT
	"	stmg	6,15,48(15)\n"
	"	lgr	14,3\n"
	"	sam31\n"
	"	diag	2,14,0x8\n"
	"	sam64\n"
	"	lgr	2,14\n"
	"	lmg	6,15,48(15)\n"
#else
	"	stm	6,15,24(15)\n"
	"	lr	14,3\n"
	"	diag	2,14,0x8\n"
	"	lr	2,14\n"
	"	lm	6,15,24(15)\n"
#endif
	"	br	14\n"
	"	.size	savesys_ipl_nss, .-savesys_ipl_nss\n"
	"	.previous\n");

static __initdata char upper_command_line[COMMAND_LINE_SIZE];

static noinline __init void create_kernel_nss(void)
{
	unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
#ifdef CONFIG_BLK_DEV_INITRD
	unsigned int sinitrd_pfn, einitrd_pfn;
#endif
	int response;
	int hlen;
	size_t len;
	char *savesys_ptr;
	char defsys_cmd[DEFSYS_CMD_SIZE];
	char savesys_cmd[SAVESYS_CMD_SIZE];

	/* Do nothing if we are not running under VM */
	if (!MACHINE_IS_VM)
		return;

	/* Convert COMMAND_LINE to upper case */
	for (i = 0; i < strlen(boot_command_line); i++)
		upper_command_line[i] = toupper(boot_command_line[i]);

	savesys_ptr = strstr(upper_command_line, "SAVESYS=");

	if (!savesys_ptr)
		return;

	savesys_ptr += 8;    /* Point to the beginning of the NSS name */
	for (i = 0; i < NSS_NAME_SIZE; i++) {
		if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
			break;
		kernel_nss_name[i] = savesys_ptr[i];
	}

	stext_pfn = PFN_DOWN(__pa(&_stext));
	eshared_pfn = PFN_DOWN(__pa(&_eshared));
	end_pfn = PFN_UP(__pa(&_end));
	min_size = end_pfn << 2;

	hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
			"DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
			kernel_nss_name, stext_pfn - 1, stext_pfn,
			eshared_pfn - 1, eshared_pfn, end_pfn);

#ifdef CONFIG_BLK_DEV_INITRD
	if (INITRD_START && INITRD_SIZE) {
		sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
		einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
		min_size = einitrd_pfn << 2;
		hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
				 " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
	}
#endif

	snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
		 " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
	defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
	snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
		 kernel_nss_name, kernel_nss_name);
	savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';

	__cpcmd(defsys_cmd, NULL, 0, &response);

	if (response != 0) {
		pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
			response);
		kernel_nss_name[0] = '\0';
		return;
	}

	len = strlen(savesys_cmd);
	ASCEBC(savesys_cmd, len);
	response = savesys_ipl_nss(savesys_cmd, len);

	/* On success: response is equal to the command size,
	 *	       max SAVESYS_CMD_SIZE
	 * On error: response contains the numeric portion of cp error message.
	 *	     for SAVESYS it will be >= 263
	 *	     for missing privilege class, it will be 1
	 */
	if (response > SAVESYS_CMD_SIZE || response == 1) {
		pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
			response);
		kernel_nss_name[0] = '\0';
		return;
	}

	/* re-initialize cputime accounting. */
	sched_clock_base_cc = get_clock();
	S390_lowcore.last_update_clock = sched_clock_base_cc;
	S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
	S390_lowcore.user_timer = 0;
	S390_lowcore.system_timer = 0;
	asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));

	/* re-setup boot command line with new ipl vm parms */
	ipl_update_parameters();
	setup_boot_command_line();

	ipl_flags = IPL_NSS_VALID;
}

#else /* CONFIG_SHARED_KERNEL */

static inline void create_kernel_nss(void) { }

#endif /* CONFIG_SHARED_KERNEL */

/*
 * Clear bss memory
 */
static noinline __init void clear_bss_section(void)
{
	memset(__bss_start, 0, __bss_stop - __bss_start);
}

/*
 * Initialize storage key for kernel pages
 */
static noinline __init void init_kernel_storage_key(void)
{
	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);
}

static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);

static noinline __init void detect_machine_type(void)
{
	/* Check current-configuration-level */
	if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
		S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
		return;
	}
	/* Get virtual-machine cpu information. */
	if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !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;
}

static __init void early_pgm_check_handler(void)
{
	unsigned long addr;
	const struct exception_table_entry *fixup;

	addr = S390_lowcore.program_old_psw.addr;
	fixup = search_exception_tables(addr & PSW_ADDR_INSN);
	if (!fixup)
		disabled_wait(0);
	S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
}

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 = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
	S390_lowcore.external_new_psw = psw;
	psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
	S390_lowcore.program_new_psw = psw;
	s390_base_pgm_handler_fn = early_pgm_check_handler;
}

static noinline __init void setup_facility_list(void)
{
	unsigned long nr;

	S390_lowcore.stfl_fac_list = 0;
	asm volatile(
		"	.insn	s,0xb2b10000,0(0)\n" /* stfl */
		"0:\n"
		EX_TABLE(0b,0b) : "=m" (S390_lowcore.stfl_fac_list));
	memcpy(&S390_lowcore.stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
	nr = 4;				/* # bytes stored by stfl */
	if (test_facility(7)) {
		/* More facility bits available with stfle */
		register unsigned long reg0 asm("0") = MAX_FACILITY_BIT/64 - 1;
		asm volatile(".insn s,0xb2b00000,%0" /* stfle */
			     : "=m" (S390_lowcore.stfle_fac_list), "+d" (reg0)
			     : : "cc");
		nr = (reg0 + 1) * 8;	/* # bytes stored by stfle */
	}
	memset((char *) S390_lowcore.stfle_fac_list + nr, 0,
	       MAX_FACILITY_BIT/8 - nr);
}

static noinline __init void setup_hpage(void)
{
#ifndef CONFIG_DEBUG_PAGEALLOC
	if (!test_facility(2) || !test_facility(8))
		return;
	S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
	__ctl_set_bit(0, 23);
#endif
}

static __init void detect_mvpg(void)
{
#ifndef CONFIG_64BIT
	int rc;

	asm volatile(
		"	la	0,0\n"
		"	mvpg	%2,%2\n"
		"0:	la	%0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
	if (!rc)
		S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
#endif
}

static __init void detect_ieee(void)
{
#ifndef CONFIG_64BIT
	int rc, tmp;

	asm volatile(
		"	efpc	%1,0\n"
		"0:	la	%0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
	if (!rc)
		S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
#endif
}

static __init void detect_csp(void)
{
#ifndef CONFIG_64BIT
	int rc;

	asm volatile(
		"	la	0,0\n"
		"	la	1,0\n"
		"	la	2,4\n"
		"	csp	0,2\n"
		"0:	la	%0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
	if (!rc)
		S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
#endif
}

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

	cpu_address = stap();
	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)
{
#ifdef CONFIG_64BIT
	int rc;

	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;
#endif
}

static __init void detect_machine_facilities(void)
{
#ifdef CONFIG_64BIT
	if (test_facility(3))
		S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
	if (test_facility(8))
		S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
	if (test_facility(11))
		S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
	if (test_facility(27))
		S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
	if (test_facility(40))
		S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
#endif
}

static __init void rescue_initrd(void)
{
#ifdef CONFIG_BLK_DEV_INITRD
	unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
	/*
	 * Just like in case of IPL from VM reader we make sure there is a
	 * gap of 4MB between end of kernel and start of initrd.
	 * That way we can also be sure that saving an NSS will succeed,
	 * which however only requires different segments.
	 */
	if (!INITRD_START || !INITRD_SIZE)
		return;
	if (INITRD_START >= min_initrd_addr)
		return;
	memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
	INITRD_START = min_initrd_addr;
#endif
}

/* Set up boot command line */
static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
{
	char *parm, *delim;
	size_t rc, len;

	len = strlen(boot_command_line);

	delim = boot_command_line + len;	/* '\0' character position */
	parm  = boot_command_line + len + 1;	/* append right after '\0' */

	rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
	if (rc) {
		if (*parm == '=')
			memmove(boot_command_line, parm + 1, rc);
		else
			*delim = ' ';		/* replace '\0' with space */
	}
}

static void __init setup_boot_command_line(void)
{
	int i;

	/* convert arch command line to ascii */
	for (i = 0; i < ARCH_COMMAND_LINE_SIZE; i++)
		if (COMMAND_LINE[i] & 0x80)
			break;
	if (i < ARCH_COMMAND_LINE_SIZE)
		EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
	COMMAND_LINE[ARCH_COMMAND_LINE_SIZE-1] = 0;

	/* copy arch command line */
	strlcpy(boot_command_line, strstrip(COMMAND_LINE),
		ARCH_COMMAND_LINE_SIZE);

	/* append IPL PARM data to the boot command line */
	if (MACHINE_IS_VM)
		append_to_cmdline(append_ipl_vmparm);

	append_to_cmdline(append_ipl_scpdata);
}


/*
 * Save ipl parameters, clear bss memory, initialize storage keys
 * and create a kernel NSS at startup if the SAVESYS= parm is defined
 */
void __init startup_init(void)
{
	reset_tod_clock();
	ipl_save_parameters();
	rescue_initrd();
	clear_bss_section();
	init_kernel_storage_key();
	lockdep_init();
	lockdep_off();
	sort_main_extable();
	setup_lowcore_early();
	setup_facility_list();
	detect_machine_type();
	ipl_update_parameters();
	setup_boot_command_line();
	create_kernel_nss();
	detect_mvpg();
	detect_ieee();
	detect_csp();
	detect_diag9c();
	detect_diag44();
	detect_machine_facilities();
	setup_hpage();
	sclp_facilities_detect();
	detect_memory_layout(memory_chunk);
#ifdef CONFIG_DYNAMIC_FTRACE
	S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
#endif
	lockdep_on();
}