xref: /linux/arch/s390/kernel/setup.c (revision 2a2153a2bac7d9388b661a18d49707a8d885b231)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999, 2012
5  *    Author(s): Hartmut Penner (hp@de.ibm.com),
6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *
8  *  Derived from "arch/i386/kernel/setup.c"
9  *    Copyright (C) 1995, Linus Torvalds
10  */
11 
12 /*
13  * This file handles the architecture-dependent parts of initialization
14  */
15 
16 #define KMSG_COMPONENT "setup"
17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
18 
19 #include <linux/errno.h>
20 #include <linux/export.h>
21 #include <linux/sched.h>
22 #include <linux/sched/task.h>
23 #include <linux/cpu.h>
24 #include <linux/kernel.h>
25 #include <linux/memblock.h>
26 #include <linux/mm.h>
27 #include <linux/stddef.h>
28 #include <linux/unistd.h>
29 #include <linux/ptrace.h>
30 #include <linux/random.h>
31 #include <linux/user.h>
32 #include <linux/tty.h>
33 #include <linux/ioport.h>
34 #include <linux/delay.h>
35 #include <linux/init.h>
36 #include <linux/initrd.h>
37 #include <linux/root_dev.h>
38 #include <linux/console.h>
39 #include <linux/kernel_stat.h>
40 #include <linux/dma-map-ops.h>
41 #include <linux/device.h>
42 #include <linux/notifier.h>
43 #include <linux/pfn.h>
44 #include <linux/ctype.h>
45 #include <linux/reboot.h>
46 #include <linux/topology.h>
47 #include <linux/kexec.h>
48 #include <linux/crash_dump.h>
49 #include <linux/memory.h>
50 #include <linux/start_kernel.h>
51 #include <linux/hugetlb.h>
52 #include <linux/kmemleak.h>
53 
54 #include <asm/archrandom.h>
55 #include <asm/boot_data.h>
56 #include <asm/machine.h>
57 #include <asm/ipl.h>
58 #include <asm/facility.h>
59 #include <asm/smp.h>
60 #include <asm/mmu_context.h>
61 #include <asm/cpcmd.h>
62 #include <asm/abs_lowcore.h>
63 #include <asm/nmi.h>
64 #include <asm/irq.h>
65 #include <asm/page.h>
66 #include <asm/ptrace.h>
67 #include <asm/sections.h>
68 #include <asm/ebcdic.h>
69 #include <asm/diag.h>
70 #include <asm/os_info.h>
71 #include <asm/sclp.h>
72 #include <asm/stacktrace.h>
73 #include <asm/sysinfo.h>
74 #include <asm/numa.h>
75 #include <asm/alternative.h>
76 #include <asm/nospec-branch.h>
77 #include <asm/physmem_info.h>
78 #include <asm/maccess.h>
79 #include <asm/uv.h>
80 #include <asm/asm-offsets.h>
81 #include "entry.h"
82 
83 /*
84  * Machine setup..
85  */
86 unsigned int console_mode = 0;
87 EXPORT_SYMBOL(console_mode);
88 
89 unsigned int console_devno = -1;
90 EXPORT_SYMBOL(console_devno);
91 
92 unsigned int console_irq = -1;
93 EXPORT_SYMBOL(console_irq);
94 
95 /*
96  * Some code and data needs to stay below 2 GB, even when the kernel would be
97  * relocated above 2 GB, because it has to use 31 bit addresses.
98  * Such code and data is part of the .amode31 section.
99  */
100 char __amode31_ref *__samode31 = _samode31;
101 char __amode31_ref *__eamode31 = _eamode31;
102 char __amode31_ref *__stext_amode31 = _stext_amode31;
103 char __amode31_ref *__etext_amode31 = _etext_amode31;
104 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
105 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
106 
107 /*
108  * Control registers CR2, CR5 and CR15 are initialized with addresses
109  * of tables that must be placed below 2G which is handled by the AMODE31
110  * sections.
111  * Because the AMODE31 sections are relocated below 2G at startup,
112  * the content of control registers CR2, CR5 and CR15 must be updated
113  * with new addresses after the relocation. The initial initialization of
114  * control registers occurs in head64.S and then gets updated again after AMODE31
115  * relocation. We must access the relevant AMODE31 tables indirectly via
116  * pointers placed in the .amode31.refs linker section. Those pointers get
117  * updated automatically during AMODE31 relocation and always contain a valid
118  * address within AMODE31 sections.
119  */
120 
121 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
122 
123 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
124 	[1] = 0xffffffffffffffff
125 };
126 
127 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
128 	0x80000000, 0, 0, 0,
129 	0x80000000, 0, 0, 0,
130 	0x80000000, 0, 0, 0,
131 	0x80000000, 0, 0, 0,
132 	0x80000000, 0, 0, 0,
133 	0x80000000, 0, 0, 0,
134 	0x80000000, 0, 0, 0,
135 	0x80000000, 0, 0, 0
136 };
137 
138 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
139 	0, 0, 0x89000000, 0,
140 	0, 0, 0x8a000000, 0
141 };
142 
143 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
144 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
145 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
146 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
147 
148 unsigned long __bootdata_preserved(max_mappable);
149 struct physmem_info __bootdata(physmem_info);
150 
151 struct vm_layout __bootdata_preserved(vm_layout);
152 EXPORT_SYMBOL(vm_layout);
153 int __bootdata_preserved(__kaslr_enabled);
154 unsigned int __bootdata_preserved(zlib_dfltcc_support);
155 EXPORT_SYMBOL(zlib_dfltcc_support);
156 u64 __bootdata_preserved(stfle_fac_list[16]);
157 EXPORT_SYMBOL(stfle_fac_list);
158 struct oldmem_data __bootdata_preserved(oldmem_data);
159 
160 char __bootdata(boot_rb)[PAGE_SIZE * 2];
161 bool __bootdata(boot_earlyprintk);
162 size_t __bootdata(boot_rb_off);
163 char __bootdata(bootdebug_filter)[128];
164 bool __bootdata(bootdebug);
165 
166 unsigned long __bootdata_preserved(VMALLOC_START);
167 EXPORT_SYMBOL(VMALLOC_START);
168 
169 unsigned long __bootdata_preserved(VMALLOC_END);
170 EXPORT_SYMBOL(VMALLOC_END);
171 
172 struct page *__bootdata_preserved(vmemmap);
173 EXPORT_SYMBOL(vmemmap);
174 unsigned long __bootdata_preserved(vmemmap_size);
175 
176 unsigned long __bootdata_preserved(MODULES_VADDR);
177 unsigned long __bootdata_preserved(MODULES_END);
178 
179 /* An array with a pointer to the lowcore of every CPU. */
180 struct lowcore *lowcore_ptr[NR_CPUS];
181 EXPORT_SYMBOL(lowcore_ptr);
182 
183 /*
184  * The Write Back bit position in the physaddr is given by the SLPC PCI.
185  * Leaving the mask zero always uses write through which is safe
186  */
187 unsigned long mio_wb_bit_mask __ro_after_init;
188 
189 /*
190  * This is set up by the setup-routine at boot-time
191  * for S390 need to find out, what we have to setup
192  * using address 0x10400 ...
193  */
194 
195 #include <asm/setup.h>
196 
197 /*
198  * condev= and conmode= setup parameter.
199  */
200 
201 static int __init condev_setup(char *str)
202 {
203 	int vdev;
204 
205 	vdev = simple_strtoul(str, &str, 0);
206 	if (vdev >= 0 && vdev < 65536) {
207 		console_devno = vdev;
208 		console_irq = -1;
209 	}
210 	return 1;
211 }
212 
213 __setup("condev=", condev_setup);
214 
215 static void __init set_preferred_console(void)
216 {
217 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
218 		add_preferred_console("ttyS", 0, NULL);
219 	else if (CONSOLE_IS_3270)
220 		add_preferred_console("tty3270", 0, NULL);
221 	else if (CONSOLE_IS_VT220)
222 		add_preferred_console("ttysclp", 0, NULL);
223 	else if (CONSOLE_IS_HVC)
224 		add_preferred_console("hvc", 0, NULL);
225 }
226 
227 static int __init conmode_setup(char *str)
228 {
229 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
230 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
231                 SET_CONSOLE_SCLP;
232 #endif
233 #if defined(CONFIG_TN3215_CONSOLE)
234 	if (!strcmp(str, "3215"))
235 		SET_CONSOLE_3215;
236 #endif
237 #if defined(CONFIG_TN3270_CONSOLE)
238 	if (!strcmp(str, "3270"))
239 		SET_CONSOLE_3270;
240 #endif
241 	set_preferred_console();
242         return 1;
243 }
244 
245 __setup("conmode=", conmode_setup);
246 
247 static void __init conmode_default(void)
248 {
249 	char query_buffer[1024];
250 	char *ptr;
251 
252 	if (machine_is_vm()) {
253 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
254 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
255 		ptr = strstr(query_buffer, "SUBCHANNEL =");
256 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
257 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
258 		ptr = strstr(query_buffer, "CONMODE");
259 		/*
260 		 * Set the conmode to 3215 so that the device recognition
261 		 * will set the cu_type of the console to 3215. If the
262 		 * conmode is 3270 and we don't set it back then both
263 		 * 3215 and the 3270 driver will try to access the console
264 		 * device (3215 as console and 3270 as normal tty).
265 		 */
266 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
267 		if (ptr == NULL) {
268 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
269 			SET_CONSOLE_SCLP;
270 #endif
271 			return;
272 		}
273 		if (str_has_prefix(ptr + 8, "3270")) {
274 #if defined(CONFIG_TN3270_CONSOLE)
275 			SET_CONSOLE_3270;
276 #elif defined(CONFIG_TN3215_CONSOLE)
277 			SET_CONSOLE_3215;
278 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
279 			SET_CONSOLE_SCLP;
280 #endif
281 		} else if (str_has_prefix(ptr + 8, "3215")) {
282 #if defined(CONFIG_TN3215_CONSOLE)
283 			SET_CONSOLE_3215;
284 #elif defined(CONFIG_TN3270_CONSOLE)
285 			SET_CONSOLE_3270;
286 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
287 			SET_CONSOLE_SCLP;
288 #endif
289 		}
290 	} else if (machine_is_kvm()) {
291 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
292 			SET_CONSOLE_VT220;
293 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
294 			SET_CONSOLE_SCLP;
295 		else
296 			SET_CONSOLE_HVC;
297 	} else {
298 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
299 		SET_CONSOLE_SCLP;
300 #endif
301 	}
302 }
303 
304 #ifdef CONFIG_CRASH_DUMP
305 static void __init setup_zfcpdump(void)
306 {
307 	if (!is_ipl_type_dump())
308 		return;
309 	if (oldmem_data.start)
310 		return;
311 	strlcat(boot_command_line, " cio_ignore=all,!ipldev,!condev", COMMAND_LINE_SIZE);
312 	console_loglevel = 2;
313 }
314 #else
315 static inline void setup_zfcpdump(void) {}
316 #endif /* CONFIG_CRASH_DUMP */
317 
318  /*
319  * Reboot, halt and power_off stubs. They just call _machine_restart,
320  * _machine_halt or _machine_power_off.
321  */
322 
323 void machine_restart(char *command)
324 {
325 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
326 		/*
327 		 * Only unblank the console if we are called in enabled
328 		 * context or a bust_spinlocks cleared the way for us.
329 		 */
330 		console_unblank();
331 	_machine_restart(command);
332 }
333 
334 void machine_halt(void)
335 {
336 	if (!in_interrupt() || oops_in_progress)
337 		/*
338 		 * Only unblank the console if we are called in enabled
339 		 * context or a bust_spinlocks cleared the way for us.
340 		 */
341 		console_unblank();
342 	_machine_halt();
343 }
344 
345 void machine_power_off(void)
346 {
347 	if (!in_interrupt() || oops_in_progress)
348 		/*
349 		 * Only unblank the console if we are called in enabled
350 		 * context or a bust_spinlocks cleared the way for us.
351 		 */
352 		console_unblank();
353 	_machine_power_off();
354 }
355 
356 /*
357  * Dummy power off function.
358  */
359 void (*pm_power_off)(void) = machine_power_off;
360 EXPORT_SYMBOL_GPL(pm_power_off);
361 
362 void *restart_stack;
363 
364 unsigned long stack_alloc(void)
365 {
366 	void *stack;
367 
368 	stack = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
369 			       NUMA_NO_NODE, __builtin_return_address(0));
370 	kmemleak_not_leak(stack);
371 	return (unsigned long)stack;
372 }
373 
374 void stack_free(unsigned long stack)
375 {
376 	vfree((void *)stack);
377 }
378 
379 static unsigned long __init stack_alloc_early(void)
380 {
381 	unsigned long stack;
382 
383 	stack = (unsigned long)memblock_alloc_or_panic(THREAD_SIZE, THREAD_SIZE);
384 	return stack;
385 }
386 
387 static void __init setup_lowcore(void)
388 {
389 	struct lowcore *lc, *abs_lc;
390 
391 	/*
392 	 * Setup lowcore for boot cpu
393 	 */
394 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
395 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
396 	if (!lc)
397 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
398 		      __func__, sizeof(*lc), sizeof(*lc));
399 
400 	lc->pcpu = (unsigned long)per_cpu_ptr(&pcpu_devices, 0);
401 	lc->restart_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT;
402 	lc->restart_psw.addr = __pa(restart_int_handler);
403 	lc->external_new_psw.mask = PSW_KERNEL_BITS;
404 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
405 	lc->svc_new_psw.mask = PSW_KERNEL_BITS;
406 	lc->svc_new_psw.addr = (unsigned long) system_call;
407 	lc->program_new_psw.mask = PSW_KERNEL_BITS;
408 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
409 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
410 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
411 	lc->io_new_psw.mask = PSW_KERNEL_BITS;
412 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
413 	lc->clock_comparator = clock_comparator_max;
414 	lc->current_task = (unsigned long)&init_task;
415 	lc->lpp = LPP_MAGIC;
416 	lc->preempt_count = get_lowcore()->preempt_count;
417 	nmi_alloc_mcesa_early(&lc->mcesad);
418 	lc->sys_enter_timer = get_lowcore()->sys_enter_timer;
419 	lc->exit_timer = get_lowcore()->exit_timer;
420 	lc->user_timer = get_lowcore()->user_timer;
421 	lc->system_timer = get_lowcore()->system_timer;
422 	lc->steal_timer = get_lowcore()->steal_timer;
423 	lc->last_update_timer = get_lowcore()->last_update_timer;
424 	lc->last_update_clock = get_lowcore()->last_update_clock;
425 	/*
426 	 * Allocate the global restart stack which is the same for
427 	 * all CPUs in case *one* of them does a PSW restart.
428 	 */
429 	restart_stack = (void *)(stack_alloc_early() + STACK_INIT_OFFSET);
430 	lc->mcck_stack = stack_alloc_early() + STACK_INIT_OFFSET;
431 	lc->async_stack = stack_alloc_early() + STACK_INIT_OFFSET;
432 	lc->nodat_stack = stack_alloc_early() + STACK_INIT_OFFSET;
433 	lc->kernel_stack = get_lowcore()->kernel_stack;
434 	/*
435 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
436 	 * restart data to the absolute zero lowcore. This is necessary if
437 	 * PSW restart is done on an offline CPU that has lowcore zero.
438 	 */
439 	lc->restart_stack = (unsigned long) restart_stack;
440 	lc->restart_fn = (unsigned long) do_restart;
441 	lc->restart_data = 0;
442 	lc->restart_source = -1U;
443 	lc->spinlock_lockval = arch_spin_lockval(0);
444 	lc->spinlock_index = 0;
445 	arch_spin_lock_setup(0);
446 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
447 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
448 	lc->preempt_count = PREEMPT_DISABLED;
449 	lc->kernel_asce = get_lowcore()->kernel_asce;
450 	lc->user_asce = get_lowcore()->user_asce;
451 
452 	system_ctlreg_init_save_area(lc);
453 	abs_lc = get_abs_lowcore();
454 	abs_lc->restart_stack = lc->restart_stack;
455 	abs_lc->restart_fn = lc->restart_fn;
456 	abs_lc->restart_data = lc->restart_data;
457 	abs_lc->restart_source = lc->restart_source;
458 	abs_lc->restart_psw = lc->restart_psw;
459 	abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
460 	abs_lc->program_new_psw = lc->program_new_psw;
461 	abs_lc->mcesad = lc->mcesad;
462 	put_abs_lowcore(abs_lc);
463 
464 	set_prefix(__pa(lc));
465 	lowcore_ptr[0] = lc;
466 	if (abs_lowcore_map(0, lowcore_ptr[0], false))
467 		panic("Couldn't setup absolute lowcore");
468 }
469 
470 static struct resource code_resource = {
471 	.name  = "Kernel code",
472 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
473 };
474 
475 static struct resource data_resource = {
476 	.name = "Kernel data",
477 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
478 };
479 
480 static struct resource bss_resource = {
481 	.name = "Kernel bss",
482 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
483 };
484 
485 static struct resource __initdata *standard_resources[] = {
486 	&code_resource,
487 	&data_resource,
488 	&bss_resource,
489 };
490 
491 static void __init setup_resources(void)
492 {
493 	struct resource *res, *std_res, *sub_res;
494 	phys_addr_t start, end;
495 	int j;
496 	u64 i;
497 
498 	code_resource.start = __pa_symbol(_text);
499 	code_resource.end = __pa_symbol(_etext) - 1;
500 	data_resource.start = __pa_symbol(_etext);
501 	data_resource.end = __pa_symbol(_edata) - 1;
502 	bss_resource.start = __pa_symbol(__bss_start);
503 	bss_resource.end = __pa_symbol(__bss_stop) - 1;
504 
505 	for_each_mem_range(i, &start, &end) {
506 		res = memblock_alloc_or_panic(sizeof(*res), 8);
507 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
508 
509 		res->name = "System RAM";
510 		res->start = start;
511 		/*
512 		 * In memblock, end points to the first byte after the
513 		 * range while in resources, end points to the last byte in
514 		 * the range.
515 		 */
516 		res->end = end - 1;
517 		request_resource(&iomem_resource, res);
518 
519 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
520 			std_res = standard_resources[j];
521 			if (std_res->start < res->start ||
522 			    std_res->start > res->end)
523 				continue;
524 			if (std_res->end > res->end) {
525 				sub_res = memblock_alloc_or_panic(sizeof(*sub_res), 8);
526 				*sub_res = *std_res;
527 				sub_res->end = res->end;
528 				std_res->start = res->end + 1;
529 				request_resource(res, sub_res);
530 			} else {
531 				request_resource(res, std_res);
532 			}
533 		}
534 	}
535 #ifdef CONFIG_CRASH_DUMP
536 	/*
537 	 * Re-add removed crash kernel memory as reserved memory. This makes
538 	 * sure it will be mapped with the identity mapping and struct pages
539 	 * will be created, so it can be resized later on.
540 	 * However add it later since the crash kernel resource should not be
541 	 * part of the System RAM resource.
542 	 */
543 	if (crashk_res.end) {
544 		memblock_add_node(crashk_res.start, resource_size(&crashk_res),
545 				  0, MEMBLOCK_NONE);
546 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
547 		insert_resource(&iomem_resource, &crashk_res);
548 	}
549 #endif
550 }
551 
552 static void __init setup_memory_end(void)
553 {
554 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
555 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
556 }
557 
558 #ifdef CONFIG_CRASH_DUMP
559 
560 /*
561  * When kdump is enabled, we have to ensure that no memory from the area
562  * [0 - crashkernel memory size] is set offline - it will be exchanged with
563  * the crashkernel memory region when kdump is triggered. The crashkernel
564  * memory region can never get offlined (pages are unmovable).
565  */
566 static int kdump_mem_notifier(struct notifier_block *nb,
567 			      unsigned long action, void *data)
568 {
569 	struct memory_notify *arg = data;
570 
571 	if (action != MEM_GOING_OFFLINE)
572 		return NOTIFY_OK;
573 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
574 		return NOTIFY_BAD;
575 	return NOTIFY_OK;
576 }
577 
578 static struct notifier_block kdump_mem_nb = {
579 	.notifier_call = kdump_mem_notifier,
580 };
581 
582 #endif
583 
584 /*
585  * Reserve page tables created by decompressor
586  */
587 static void __init reserve_pgtables(void)
588 {
589 	unsigned long start, end;
590 	struct reserved_range *range;
591 
592 	for_each_physmem_reserved_type_range(RR_VMEM, range, &start, &end)
593 		memblock_reserve(start, end - start);
594 }
595 
596 /*
597  * Reserve memory for kdump kernel to be loaded with kexec
598  */
599 static void __init reserve_crashkernel(void)
600 {
601 #ifdef CONFIG_CRASH_DUMP
602 	unsigned long long crash_base, crash_size;
603 	phys_addr_t low, high;
604 	int rc;
605 
606 	rc = parse_crashkernel(boot_command_line, ident_map_size,
607 			       &crash_size, &crash_base, NULL, NULL, NULL);
608 
609 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
610 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
611 	if (rc || crash_size == 0)
612 		return;
613 
614 	if (memblock.memory.regions[0].size < crash_size) {
615 		pr_info("crashkernel reservation failed: %s\n",
616 			"first memory chunk must be at least crashkernel size");
617 		return;
618 	}
619 
620 	low = crash_base ?: oldmem_data.start;
621 	high = low + crash_size;
622 	if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
623 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
624 		crash_base = low;
625 	} else {
626 		/* Find suitable area in free memory */
627 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
628 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
629 
630 		if (crash_base && crash_base < low) {
631 			pr_info("crashkernel reservation failed: %s\n",
632 				"crash_base too low");
633 			return;
634 		}
635 		low = crash_base ?: low;
636 		crash_base = memblock_phys_alloc_range(crash_size,
637 						       KEXEC_CRASH_MEM_ALIGN,
638 						       low, high);
639 	}
640 
641 	if (!crash_base) {
642 		pr_info("crashkernel reservation failed: %s\n",
643 			"no suitable area found");
644 		return;
645 	}
646 
647 	if (register_memory_notifier(&kdump_mem_nb)) {
648 		memblock_phys_free(crash_base, crash_size);
649 		return;
650 	}
651 
652 	if (!oldmem_data.start && machine_is_vm())
653 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
654 	crashk_res.start = crash_base;
655 	crashk_res.end = crash_base + crash_size - 1;
656 	memblock_remove(crash_base, crash_size);
657 	pr_info("Reserving %lluMB of memory at %lluMB "
658 		"for crashkernel (System RAM: %luMB)\n",
659 		crash_size >> 20, crash_base >> 20,
660 		(unsigned long)memblock.memory.total_size >> 20);
661 	os_info_crashkernel_add(crash_base, crash_size);
662 #endif
663 }
664 
665 /*
666  * Reserve the initrd from being used by memblock
667  */
668 static void __init reserve_initrd(void)
669 {
670 	unsigned long addr, size;
671 
672 	if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD) || !get_physmem_reserved(RR_INITRD, &addr, &size))
673 		return;
674 	initrd_start = (unsigned long)__va(addr);
675 	initrd_end = initrd_start + size;
676 	memblock_reserve(addr, size);
677 }
678 
679 /*
680  * Reserve the memory area used to pass the certificate lists
681  */
682 static void __init reserve_certificate_list(void)
683 {
684 	if (ipl_cert_list_addr)
685 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
686 }
687 
688 static void __init reserve_physmem_info(void)
689 {
690 	unsigned long addr, size;
691 
692 	if (get_physmem_reserved(RR_MEM_DETECT_EXT, &addr, &size))
693 		memblock_reserve(addr, size);
694 }
695 
696 static void __init free_physmem_info(void)
697 {
698 	unsigned long addr, size;
699 
700 	if (get_physmem_reserved(RR_MEM_DETECT_EXT, &addr, &size))
701 		memblock_phys_free(addr, size);
702 }
703 
704 static void __init memblock_add_physmem_info(void)
705 {
706 	unsigned long start, end;
707 	int i;
708 
709 	pr_debug("physmem info source: %s (%hhd)\n",
710 		 get_physmem_info_source(), physmem_info.info_source);
711 	/* keep memblock lists close to the kernel */
712 	memblock_set_bottom_up(true);
713 	for_each_physmem_usable_range(i, &start, &end)
714 		memblock_add(start, end - start);
715 	for_each_physmem_online_range(i, &start, &end)
716 		memblock_physmem_add(start, end - start);
717 	memblock_set_bottom_up(false);
718 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
719 }
720 
721 static void __init setup_high_memory(void)
722 {
723 	high_memory = __va(ident_map_size);
724 }
725 
726 /*
727  * Reserve memory used for lowcore.
728  */
729 static void __init reserve_lowcore(void)
730 {
731 	void *lowcore_start = get_lowcore();
732 	void *lowcore_end = lowcore_start + sizeof(struct lowcore);
733 	void *start, *end;
734 
735 	if (absolute_pointer(__identity_base) < lowcore_end) {
736 		start = max(lowcore_start, (void *)__identity_base);
737 		end = min(lowcore_end, (void *)(__identity_base + ident_map_size));
738 		memblock_reserve(__pa(start), __pa(end));
739 	}
740 }
741 
742 /*
743  * Reserve memory used for absolute lowcore/command line/kernel image.
744  */
745 static void __init reserve_kernel(void)
746 {
747 	memblock_reserve(0, STARTUP_NORMAL_OFFSET);
748 	memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
749 	memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
750 	memblock_reserve(physmem_info.reserved[RR_AMODE31].start, __eamode31 - __samode31);
751 	memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
752 	memblock_reserve(__pa(_stext), _end - _stext);
753 }
754 
755 static void __init setup_memory(void)
756 {
757 	phys_addr_t start, end;
758 	u64 i;
759 
760 	/*
761 	 * Init storage key for present memory
762 	 */
763 	for_each_mem_range(i, &start, &end)
764 		storage_key_init_range(start, end);
765 
766 	psw_set_key(PAGE_DEFAULT_KEY);
767 }
768 
769 static void __init relocate_amode31_section(void)
770 {
771 	unsigned long amode31_size = __eamode31 - __samode31;
772 	long amode31_offset, *ptr;
773 
774 	amode31_offset = AMODE31_START - (unsigned long)__samode31;
775 	pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
776 
777 	/* Move original AMODE31 section to the new one */
778 	memmove((void *)physmem_info.reserved[RR_AMODE31].start, __samode31, amode31_size);
779 	/* Zero out the old AMODE31 section to catch invalid accesses within it */
780 	memset(__samode31, 0, amode31_size);
781 
782 	/* Update all AMODE31 region references */
783 	for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
784 		*ptr += amode31_offset;
785 }
786 
787 /* This must be called after AMODE31 relocation */
788 static void __init setup_cr(void)
789 {
790 	union ctlreg2 cr2;
791 	union ctlreg5 cr5;
792 	union ctlreg15 cr15;
793 
794 	__ctl_duct[1] = (unsigned long)__ctl_aste;
795 	__ctl_duct[2] = (unsigned long)__ctl_aste;
796 	__ctl_duct[4] = (unsigned long)__ctl_duald;
797 
798 	/* Update control registers CR2, CR5 and CR15 */
799 	local_ctl_store(2, &cr2.reg);
800 	local_ctl_store(5, &cr5.reg);
801 	local_ctl_store(15, &cr15.reg);
802 	cr2.ducto = (unsigned long)__ctl_duct >> 6;
803 	cr5.pasteo = (unsigned long)__ctl_duct >> 6;
804 	cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
805 	system_ctl_load(2, &cr2.reg);
806 	system_ctl_load(5, &cr5.reg);
807 	system_ctl_load(15, &cr15.reg);
808 }
809 
810 /*
811  * Add system information as device randomness
812  */
813 static void __init setup_randomness(void)
814 {
815 	struct sysinfo_3_2_2 *vmms;
816 
817 	vmms = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
818 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
819 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
820 	memblock_free(vmms, PAGE_SIZE);
821 
822 	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
823 		static_branch_enable(&s390_arch_random_available);
824 }
825 
826 /*
827  * Issue diagnose 318 to set the control program name and
828  * version codes.
829  */
830 static void __init setup_control_program_code(void)
831 {
832 	union diag318_info diag318_info = {
833 		.cpnc = CPNC_LINUX,
834 		.cpvc = 0,
835 	};
836 
837 	if (!sclp.has_diag318)
838 		return;
839 
840 	diag_stat_inc(DIAG_STAT_X318);
841 	asm volatile("diag %0,0,0x318" : : "d" (diag318_info.val));
842 }
843 
844 /*
845  * Print the component list from the IPL report
846  */
847 static void __init log_component_list(void)
848 {
849 	struct ipl_rb_component_entry *ptr, *end;
850 	char *str;
851 
852 	if (!early_ipl_comp_list_addr)
853 		return;
854 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
855 		pr_info("Linux is running with Secure-IPL enabled\n");
856 	else
857 		pr_info("Linux is running with Secure-IPL disabled\n");
858 	ptr = __va(early_ipl_comp_list_addr);
859 	end = (void *) ptr + early_ipl_comp_list_size;
860 	pr_info("The IPL report contains the following components:\n");
861 	while (ptr < end) {
862 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
863 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
864 				str = "signed, verified";
865 			else
866 				str = "signed, verification failed";
867 		} else {
868 			str = "not signed";
869 		}
870 		pr_info("%016llx - %016llx (%s)\n",
871 			ptr->addr, ptr->addr + ptr->len, str);
872 		ptr++;
873 	}
874 }
875 
876 /*
877  * Print avoiding interpretation of % in buf and taking bootdebug option
878  * into consideration.
879  */
880 static void __init print_rb_entry(const char *buf)
881 {
882 	char fmt[] = KERN_SOH "0boot: %s";
883 	int level = printk_get_level(buf);
884 
885 	buf = skip_timestamp(printk_skip_level(buf));
886 	if (level == KERN_DEBUG[1] && (!bootdebug || !bootdebug_filter_match(buf)))
887 		return;
888 
889 	fmt[1] = level;
890 	printk(fmt, buf);
891 }
892 
893 /*
894  * Setup function called from init/main.c just after the banner
895  * was printed.
896  */
897 
898 void __init setup_arch(char **cmdline_p)
899 {
900         /*
901          * print what head.S has found out about the machine
902          */
903 	if (machine_is_vm())
904 		pr_info("Linux is running as a z/VM "
905 			"guest operating system in 64-bit mode\n");
906 	else if (machine_is_kvm())
907 		pr_info("Linux is running under KVM in 64-bit mode\n");
908 	else if (machine_is_lpar())
909 		pr_info("Linux is running natively in 64-bit mode\n");
910 	else
911 		pr_info("Linux is running as a guest in 64-bit mode\n");
912 	/* Print decompressor messages if not already printed */
913 	if (!boot_earlyprintk)
914 		boot_rb_foreach(print_rb_entry);
915 
916 	if (machine_has_relocated_lowcore())
917 		pr_info("Lowcore relocated to 0x%px\n", get_lowcore());
918 
919 	log_component_list();
920 
921 	/* Have one command line that is parsed and saved in /proc/cmdline */
922 	/* boot_command_line has been already set up in early.c */
923 	*cmdline_p = boot_command_line;
924 
925         ROOT_DEV = Root_RAM0;
926 
927 	setup_initial_init_mm(_text, _etext, _edata, _end);
928 
929 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
930 		nospec_auto_detect();
931 
932 	jump_label_init();
933 	parse_early_param();
934 #ifdef CONFIG_CRASH_DUMP
935 	/* Deactivate elfcorehdr= kernel parameter */
936 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
937 #endif
938 
939 	os_info_init();
940 	setup_ipl();
941 	setup_control_program_code();
942 
943 	/* Do some memory reservations *before* memory is added to memblock */
944 	reserve_pgtables();
945 	reserve_lowcore();
946 	reserve_kernel();
947 	reserve_initrd();
948 	reserve_certificate_list();
949 	reserve_physmem_info();
950 	memblock_set_current_limit(ident_map_size);
951 	memblock_allow_resize();
952 
953 	/* Get information about *all* installed memory */
954 	memblock_add_physmem_info();
955 
956 	free_physmem_info();
957 	setup_memory_end();
958 	setup_high_memory();
959 	memblock_dump_all();
960 	setup_memory();
961 
962 	relocate_amode31_section();
963 	setup_cr();
964 	setup_uv();
965 	dma_contiguous_reserve(ident_map_size);
966 	vmcp_cma_reserve();
967 	if (cpu_has_edat2())
968 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
969 
970 	reserve_crashkernel();
971 #ifdef CONFIG_CRASH_DUMP
972 	/*
973 	 * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
974 	 * Therefore CPU and device initialization should be done afterwards.
975 	 */
976 	smp_save_dump_secondary_cpus();
977 #endif
978 
979 	setup_resources();
980 	setup_lowcore();
981 	smp_fill_possible_mask();
982 	cpu_detect_mhz_feature();
983         cpu_init();
984 	numa_setup();
985 	smp_detect_cpus();
986 	topology_init_early();
987 	setup_protection_map();
988 	/*
989 	 * Create kernel page tables.
990 	 */
991         paging_init();
992 
993 	/*
994 	 * After paging_init created the kernel page table, the new PSWs
995 	 * in lowcore can now run with DAT enabled.
996 	 */
997 #ifdef CONFIG_CRASH_DUMP
998 	smp_save_dump_ipl_cpu();
999 #endif
1000 
1001         /* Setup default console */
1002 	conmode_default();
1003 	set_preferred_console();
1004 
1005 	apply_alternative_instructions();
1006 	if (IS_ENABLED(CONFIG_EXPOLINE))
1007 		nospec_init_branches();
1008 
1009 	/* Setup zfcp/nvme dump support */
1010 	setup_zfcpdump();
1011 
1012 	/* Add system specific data to the random pool */
1013 	setup_randomness();
1014 }
1015 
1016 void __init arch_cpu_finalize_init(void)
1017 {
1018 	sclp_init();
1019 }
1020