xref: /linux/arch/s390/kernel/setup.c (revision 73519ded992fc9dda2807450d6931002bb93cb16)
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/compat.h>
51 #include <linux/start_kernel.h>
52 #include <linux/hugetlb.h>
53 #include <linux/kmemleak.h>
54 
55 #include <asm/archrandom.h>
56 #include <asm/boot_data.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 unsigned long VMALLOC_START;
161 EXPORT_SYMBOL(VMALLOC_START);
162 
163 unsigned long VMALLOC_END;
164 EXPORT_SYMBOL(VMALLOC_END);
165 
166 struct page *vmemmap;
167 EXPORT_SYMBOL(vmemmap);
168 unsigned long vmemmap_size;
169 
170 unsigned long MODULES_VADDR;
171 unsigned long MODULES_END;
172 
173 /* An array with a pointer to the lowcore of every CPU. */
174 struct lowcore *lowcore_ptr[NR_CPUS];
175 EXPORT_SYMBOL(lowcore_ptr);
176 
177 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
178 
179 /*
180  * The Write Back bit position in the physaddr is given by the SLPC PCI.
181  * Leaving the mask zero always uses write through which is safe
182  */
183 unsigned long mio_wb_bit_mask __ro_after_init;
184 
185 /*
186  * This is set up by the setup-routine at boot-time
187  * for S390 need to find out, what we have to setup
188  * using address 0x10400 ...
189  */
190 
191 #include <asm/setup.h>
192 
193 /*
194  * condev= and conmode= setup parameter.
195  */
196 
197 static int __init condev_setup(char *str)
198 {
199 	int vdev;
200 
201 	vdev = simple_strtoul(str, &str, 0);
202 	if (vdev >= 0 && vdev < 65536) {
203 		console_devno = vdev;
204 		console_irq = -1;
205 	}
206 	return 1;
207 }
208 
209 __setup("condev=", condev_setup);
210 
211 static void __init set_preferred_console(void)
212 {
213 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
214 		add_preferred_console("ttyS", 0, NULL);
215 	else if (CONSOLE_IS_3270)
216 		add_preferred_console("tty3270", 0, NULL);
217 	else if (CONSOLE_IS_VT220)
218 		add_preferred_console("ttysclp", 0, NULL);
219 	else if (CONSOLE_IS_HVC)
220 		add_preferred_console("hvc", 0, NULL);
221 }
222 
223 static int __init conmode_setup(char *str)
224 {
225 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
226 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
227                 SET_CONSOLE_SCLP;
228 #endif
229 #if defined(CONFIG_TN3215_CONSOLE)
230 	if (!strcmp(str, "3215"))
231 		SET_CONSOLE_3215;
232 #endif
233 #if defined(CONFIG_TN3270_CONSOLE)
234 	if (!strcmp(str, "3270"))
235 		SET_CONSOLE_3270;
236 #endif
237 	set_preferred_console();
238         return 1;
239 }
240 
241 __setup("conmode=", conmode_setup);
242 
243 static void __init conmode_default(void)
244 {
245 	char query_buffer[1024];
246 	char *ptr;
247 
248         if (MACHINE_IS_VM) {
249 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
250 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
251 		ptr = strstr(query_buffer, "SUBCHANNEL =");
252 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
253 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
254 		ptr = strstr(query_buffer, "CONMODE");
255 		/*
256 		 * Set the conmode to 3215 so that the device recognition
257 		 * will set the cu_type of the console to 3215. If the
258 		 * conmode is 3270 and we don't set it back then both
259 		 * 3215 and the 3270 driver will try to access the console
260 		 * device (3215 as console and 3270 as normal tty).
261 		 */
262 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
263 		if (ptr == NULL) {
264 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
265 			SET_CONSOLE_SCLP;
266 #endif
267 			return;
268 		}
269 		if (str_has_prefix(ptr + 8, "3270")) {
270 #if defined(CONFIG_TN3270_CONSOLE)
271 			SET_CONSOLE_3270;
272 #elif defined(CONFIG_TN3215_CONSOLE)
273 			SET_CONSOLE_3215;
274 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
275 			SET_CONSOLE_SCLP;
276 #endif
277 		} else if (str_has_prefix(ptr + 8, "3215")) {
278 #if defined(CONFIG_TN3215_CONSOLE)
279 			SET_CONSOLE_3215;
280 #elif defined(CONFIG_TN3270_CONSOLE)
281 			SET_CONSOLE_3270;
282 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
283 			SET_CONSOLE_SCLP;
284 #endif
285 		}
286 	} else if (MACHINE_IS_KVM) {
287 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
288 			SET_CONSOLE_VT220;
289 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
290 			SET_CONSOLE_SCLP;
291 		else
292 			SET_CONSOLE_HVC;
293 	} else {
294 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
295 		SET_CONSOLE_SCLP;
296 #endif
297 	}
298 }
299 
300 #ifdef CONFIG_CRASH_DUMP
301 static void __init setup_zfcpdump(void)
302 {
303 	if (!is_ipl_type_dump())
304 		return;
305 	if (oldmem_data.start)
306 		return;
307 	strlcat(boot_command_line, " cio_ignore=all,!ipldev,!condev", COMMAND_LINE_SIZE);
308 	console_loglevel = 2;
309 }
310 #else
311 static inline void setup_zfcpdump(void) {}
312 #endif /* CONFIG_CRASH_DUMP */
313 
314  /*
315  * Reboot, halt and power_off stubs. They just call _machine_restart,
316  * _machine_halt or _machine_power_off.
317  */
318 
319 void machine_restart(char *command)
320 {
321 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
322 		/*
323 		 * Only unblank the console if we are called in enabled
324 		 * context or a bust_spinlocks cleared the way for us.
325 		 */
326 		console_unblank();
327 	_machine_restart(command);
328 }
329 
330 void machine_halt(void)
331 {
332 	if (!in_interrupt() || oops_in_progress)
333 		/*
334 		 * Only unblank the console if we are called in enabled
335 		 * context or a bust_spinlocks cleared the way for us.
336 		 */
337 		console_unblank();
338 	_machine_halt();
339 }
340 
341 void machine_power_off(void)
342 {
343 	if (!in_interrupt() || oops_in_progress)
344 		/*
345 		 * Only unblank the console if we are called in enabled
346 		 * context or a bust_spinlocks cleared the way for us.
347 		 */
348 		console_unblank();
349 	_machine_power_off();
350 }
351 
352 /*
353  * Dummy power off function.
354  */
355 void (*pm_power_off)(void) = machine_power_off;
356 EXPORT_SYMBOL_GPL(pm_power_off);
357 
358 void *restart_stack;
359 
360 unsigned long stack_alloc(void)
361 {
362 #ifdef CONFIG_VMAP_STACK
363 	void *ret;
364 
365 	ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
366 			     NUMA_NO_NODE, __builtin_return_address(0));
367 	kmemleak_not_leak(ret);
368 	return (unsigned long)ret;
369 #else
370 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
371 #endif
372 }
373 
374 void stack_free(unsigned long stack)
375 {
376 #ifdef CONFIG_VMAP_STACK
377 	vfree((void *) stack);
378 #else
379 	free_pages(stack, THREAD_SIZE_ORDER);
380 #endif
381 }
382 
383 static unsigned long __init stack_alloc_early(void)
384 {
385 	unsigned long stack;
386 
387 	stack = (unsigned long)memblock_alloc_or_panic(THREAD_SIZE, THREAD_SIZE);
388 	return stack;
389 }
390 
391 static void __init setup_lowcore(void)
392 {
393 	struct lowcore *lc, *abs_lc;
394 
395 	/*
396 	 * Setup lowcore for boot cpu
397 	 */
398 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
399 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
400 	if (!lc)
401 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
402 		      __func__, sizeof(*lc), sizeof(*lc));
403 
404 	lc->pcpu = (unsigned long)per_cpu_ptr(&pcpu_devices, 0);
405 	lc->restart_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT;
406 	lc->restart_psw.addr = __pa(restart_int_handler);
407 	lc->external_new_psw.mask = PSW_KERNEL_BITS;
408 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
409 	lc->svc_new_psw.mask = PSW_KERNEL_BITS;
410 	lc->svc_new_psw.addr = (unsigned long) system_call;
411 	lc->program_new_psw.mask = PSW_KERNEL_BITS;
412 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
413 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
414 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
415 	lc->io_new_psw.mask = PSW_KERNEL_BITS;
416 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
417 	lc->clock_comparator = clock_comparator_max;
418 	lc->current_task = (unsigned long)&init_task;
419 	lc->lpp = LPP_MAGIC;
420 	lc->machine_flags = get_lowcore()->machine_flags;
421 	lc->preempt_count = get_lowcore()->preempt_count;
422 	nmi_alloc_mcesa_early(&lc->mcesad);
423 	lc->sys_enter_timer = get_lowcore()->sys_enter_timer;
424 	lc->exit_timer = get_lowcore()->exit_timer;
425 	lc->user_timer = get_lowcore()->user_timer;
426 	lc->system_timer = get_lowcore()->system_timer;
427 	lc->steal_timer = get_lowcore()->steal_timer;
428 	lc->last_update_timer = get_lowcore()->last_update_timer;
429 	lc->last_update_clock = get_lowcore()->last_update_clock;
430 	/*
431 	 * Allocate the global restart stack which is the same for
432 	 * all CPUs in case *one* of them does a PSW restart.
433 	 */
434 	restart_stack = (void *)(stack_alloc_early() + STACK_INIT_OFFSET);
435 	lc->mcck_stack = stack_alloc_early() + STACK_INIT_OFFSET;
436 	lc->async_stack = stack_alloc_early() + STACK_INIT_OFFSET;
437 	lc->nodat_stack = stack_alloc_early() + STACK_INIT_OFFSET;
438 	lc->kernel_stack = get_lowcore()->kernel_stack;
439 	/*
440 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
441 	 * restart data to the absolute zero lowcore. This is necessary if
442 	 * PSW restart is done on an offline CPU that has lowcore zero.
443 	 */
444 	lc->restart_stack = (unsigned long) restart_stack;
445 	lc->restart_fn = (unsigned long) do_restart;
446 	lc->restart_data = 0;
447 	lc->restart_source = -1U;
448 	lc->spinlock_lockval = arch_spin_lockval(0);
449 	lc->spinlock_index = 0;
450 	arch_spin_lock_setup(0);
451 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
452 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
453 	lc->preempt_count = PREEMPT_DISABLED;
454 	lc->kernel_asce = get_lowcore()->kernel_asce;
455 	lc->user_asce = get_lowcore()->user_asce;
456 
457 	system_ctlreg_init_save_area(lc);
458 	abs_lc = get_abs_lowcore();
459 	abs_lc->restart_stack = lc->restart_stack;
460 	abs_lc->restart_fn = lc->restart_fn;
461 	abs_lc->restart_data = lc->restart_data;
462 	abs_lc->restart_source = lc->restart_source;
463 	abs_lc->restart_psw = lc->restart_psw;
464 	abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
465 	abs_lc->program_new_psw = lc->program_new_psw;
466 	abs_lc->mcesad = lc->mcesad;
467 	put_abs_lowcore(abs_lc);
468 
469 	set_prefix(__pa(lc));
470 	lowcore_ptr[0] = lc;
471 	if (abs_lowcore_map(0, lowcore_ptr[0], false))
472 		panic("Couldn't setup absolute lowcore");
473 }
474 
475 static struct resource code_resource = {
476 	.name  = "Kernel code",
477 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
478 };
479 
480 static struct resource data_resource = {
481 	.name = "Kernel data",
482 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
483 };
484 
485 static struct resource bss_resource = {
486 	.name = "Kernel bss",
487 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
488 };
489 
490 static struct resource __initdata *standard_resources[] = {
491 	&code_resource,
492 	&data_resource,
493 	&bss_resource,
494 };
495 
496 static void __init setup_resources(void)
497 {
498 	struct resource *res, *std_res, *sub_res;
499 	phys_addr_t start, end;
500 	int j;
501 	u64 i;
502 
503 	code_resource.start = __pa_symbol(_text);
504 	code_resource.end = __pa_symbol(_etext) - 1;
505 	data_resource.start = __pa_symbol(_etext);
506 	data_resource.end = __pa_symbol(_edata) - 1;
507 	bss_resource.start = __pa_symbol(__bss_start);
508 	bss_resource.end = __pa_symbol(__bss_stop) - 1;
509 
510 	for_each_mem_range(i, &start, &end) {
511 		res = memblock_alloc_or_panic(sizeof(*res), 8);
512 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
513 
514 		res->name = "System RAM";
515 		res->start = start;
516 		/*
517 		 * In memblock, end points to the first byte after the
518 		 * range while in resources, end points to the last byte in
519 		 * the range.
520 		 */
521 		res->end = end - 1;
522 		request_resource(&iomem_resource, res);
523 
524 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
525 			std_res = standard_resources[j];
526 			if (std_res->start < res->start ||
527 			    std_res->start > res->end)
528 				continue;
529 			if (std_res->end > res->end) {
530 				sub_res = memblock_alloc_or_panic(sizeof(*sub_res), 8);
531 				*sub_res = *std_res;
532 				sub_res->end = res->end;
533 				std_res->start = res->end + 1;
534 				request_resource(res, sub_res);
535 			} else {
536 				request_resource(res, std_res);
537 			}
538 		}
539 	}
540 #ifdef CONFIG_CRASH_DUMP
541 	/*
542 	 * Re-add removed crash kernel memory as reserved memory. This makes
543 	 * sure it will be mapped with the identity mapping and struct pages
544 	 * will be created, so it can be resized later on.
545 	 * However add it later since the crash kernel resource should not be
546 	 * part of the System RAM resource.
547 	 */
548 	if (crashk_res.end) {
549 		memblock_add_node(crashk_res.start, resource_size(&crashk_res),
550 				  0, MEMBLOCK_NONE);
551 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
552 		insert_resource(&iomem_resource, &crashk_res);
553 	}
554 #endif
555 }
556 
557 static void __init setup_memory_end(void)
558 {
559 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
560 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
561 }
562 
563 #ifdef CONFIG_CRASH_DUMP
564 
565 /*
566  * When kdump is enabled, we have to ensure that no memory from the area
567  * [0 - crashkernel memory size] is set offline - it will be exchanged with
568  * the crashkernel memory region when kdump is triggered. The crashkernel
569  * memory region can never get offlined (pages are unmovable).
570  */
571 static int kdump_mem_notifier(struct notifier_block *nb,
572 			      unsigned long action, void *data)
573 {
574 	struct memory_notify *arg = data;
575 
576 	if (action != MEM_GOING_OFFLINE)
577 		return NOTIFY_OK;
578 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
579 		return NOTIFY_BAD;
580 	return NOTIFY_OK;
581 }
582 
583 static struct notifier_block kdump_mem_nb = {
584 	.notifier_call = kdump_mem_notifier,
585 };
586 
587 #endif
588 
589 /*
590  * Reserve page tables created by decompressor
591  */
592 static void __init reserve_pgtables(void)
593 {
594 	unsigned long start, end;
595 	struct reserved_range *range;
596 
597 	for_each_physmem_reserved_type_range(RR_VMEM, range, &start, &end)
598 		memblock_reserve(start, end - start);
599 }
600 
601 /*
602  * Reserve memory for kdump kernel to be loaded with kexec
603  */
604 static void __init reserve_crashkernel(void)
605 {
606 #ifdef CONFIG_CRASH_DUMP
607 	unsigned long long crash_base, crash_size;
608 	phys_addr_t low, high;
609 	int rc;
610 
611 	rc = parse_crashkernel(boot_command_line, ident_map_size,
612 			       &crash_size, &crash_base, NULL, NULL);
613 
614 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
615 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
616 	if (rc || crash_size == 0)
617 		return;
618 
619 	if (memblock.memory.regions[0].size < crash_size) {
620 		pr_info("crashkernel reservation failed: %s\n",
621 			"first memory chunk must be at least crashkernel size");
622 		return;
623 	}
624 
625 	low = crash_base ?: oldmem_data.start;
626 	high = low + crash_size;
627 	if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
628 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
629 		crash_base = low;
630 	} else {
631 		/* Find suitable area in free memory */
632 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
633 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
634 
635 		if (crash_base && crash_base < low) {
636 			pr_info("crashkernel reservation failed: %s\n",
637 				"crash_base too low");
638 			return;
639 		}
640 		low = crash_base ?: low;
641 		crash_base = memblock_phys_alloc_range(crash_size,
642 						       KEXEC_CRASH_MEM_ALIGN,
643 						       low, high);
644 	}
645 
646 	if (!crash_base) {
647 		pr_info("crashkernel reservation failed: %s\n",
648 			"no suitable area found");
649 		return;
650 	}
651 
652 	if (register_memory_notifier(&kdump_mem_nb)) {
653 		memblock_phys_free(crash_base, crash_size);
654 		return;
655 	}
656 
657 	if (!oldmem_data.start && MACHINE_IS_VM)
658 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
659 	crashk_res.start = crash_base;
660 	crashk_res.end = crash_base + crash_size - 1;
661 	memblock_remove(crash_base, crash_size);
662 	pr_info("Reserving %lluMB of memory at %lluMB "
663 		"for crashkernel (System RAM: %luMB)\n",
664 		crash_size >> 20, crash_base >> 20,
665 		(unsigned long)memblock.memory.total_size >> 20);
666 	os_info_crashkernel_add(crash_base, crash_size);
667 #endif
668 }
669 
670 /*
671  * Reserve the initrd from being used by memblock
672  */
673 static void __init reserve_initrd(void)
674 {
675 	unsigned long addr, size;
676 
677 	if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD) || !get_physmem_reserved(RR_INITRD, &addr, &size))
678 		return;
679 	initrd_start = (unsigned long)__va(addr);
680 	initrd_end = initrd_start + size;
681 	memblock_reserve(addr, size);
682 }
683 
684 /*
685  * Reserve the memory area used to pass the certificate lists
686  */
687 static void __init reserve_certificate_list(void)
688 {
689 	if (ipl_cert_list_addr)
690 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
691 }
692 
693 static void __init reserve_physmem_info(void)
694 {
695 	unsigned long addr, size;
696 
697 	if (get_physmem_reserved(RR_MEM_DETECT_EXTENDED, &addr, &size))
698 		memblock_reserve(addr, size);
699 }
700 
701 static void __init free_physmem_info(void)
702 {
703 	unsigned long addr, size;
704 
705 	if (get_physmem_reserved(RR_MEM_DETECT_EXTENDED, &addr, &size))
706 		memblock_phys_free(addr, size);
707 }
708 
709 static void __init memblock_add_physmem_info(void)
710 {
711 	unsigned long start, end;
712 	int i;
713 
714 	pr_debug("physmem info source: %s (%hhd)\n",
715 		 get_physmem_info_source(), physmem_info.info_source);
716 	/* keep memblock lists close to the kernel */
717 	memblock_set_bottom_up(true);
718 	for_each_physmem_usable_range(i, &start, &end)
719 		memblock_add(start, end - start);
720 	for_each_physmem_online_range(i, &start, &end)
721 		memblock_physmem_add(start, end - start);
722 	memblock_set_bottom_up(false);
723 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
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 ((void *)__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\n" : : "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  * Setup function called from init/main.c just after the banner
878  * was printed.
879  */
880 
881 void __init setup_arch(char **cmdline_p)
882 {
883         /*
884          * print what head.S has found out about the machine
885          */
886 	if (MACHINE_IS_VM)
887 		pr_info("Linux is running as a z/VM "
888 			"guest operating system in 64-bit mode\n");
889 	else if (MACHINE_IS_KVM)
890 		pr_info("Linux is running under KVM in 64-bit mode\n");
891 	else if (MACHINE_IS_LPAR)
892 		pr_info("Linux is running natively in 64-bit mode\n");
893 	else
894 		pr_info("Linux is running as a guest in 64-bit mode\n");
895 
896 	if (have_relocated_lowcore())
897 		pr_info("Lowcore relocated to 0x%px\n", get_lowcore());
898 
899 	log_component_list();
900 
901 	/* Have one command line that is parsed and saved in /proc/cmdline */
902 	/* boot_command_line has been already set up in early.c */
903 	*cmdline_p = boot_command_line;
904 
905         ROOT_DEV = Root_RAM0;
906 
907 	setup_initial_init_mm(_text, _etext, _edata, _end);
908 
909 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
910 		nospec_auto_detect();
911 
912 	jump_label_init();
913 	parse_early_param();
914 #ifdef CONFIG_CRASH_DUMP
915 	/* Deactivate elfcorehdr= kernel parameter */
916 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
917 #endif
918 
919 	os_info_init();
920 	setup_ipl();
921 	setup_control_program_code();
922 
923 	/* Do some memory reservations *before* memory is added to memblock */
924 	reserve_pgtables();
925 	reserve_lowcore();
926 	reserve_kernel();
927 	reserve_initrd();
928 	reserve_certificate_list();
929 	reserve_physmem_info();
930 	memblock_set_current_limit(ident_map_size);
931 	memblock_allow_resize();
932 
933 	/* Get information about *all* installed memory */
934 	memblock_add_physmem_info();
935 
936 	free_physmem_info();
937 	setup_memory_end();
938 	memblock_dump_all();
939 	setup_memory();
940 
941 	relocate_amode31_section();
942 	setup_cr();
943 	setup_uv();
944 	dma_contiguous_reserve(ident_map_size);
945 	vmcp_cma_reserve();
946 	if (MACHINE_HAS_EDAT2)
947 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
948 
949 	reserve_crashkernel();
950 #ifdef CONFIG_CRASH_DUMP
951 	/*
952 	 * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
953 	 * Therefore CPU and device initialization should be done afterwards.
954 	 */
955 	smp_save_dump_secondary_cpus();
956 #endif
957 
958 	setup_resources();
959 	setup_lowcore();
960 	smp_fill_possible_mask();
961 	cpu_detect_mhz_feature();
962         cpu_init();
963 	numa_setup();
964 	smp_detect_cpus();
965 	topology_init_early();
966 
967 	if (test_facility(193))
968 		static_branch_enable(&cpu_has_bear);
969 
970 	/*
971 	 * Create kernel page tables.
972 	 */
973         paging_init();
974 
975 	/*
976 	 * After paging_init created the kernel page table, the new PSWs
977 	 * in lowcore can now run with DAT enabled.
978 	 */
979 #ifdef CONFIG_CRASH_DUMP
980 	smp_save_dump_ipl_cpu();
981 #endif
982 
983         /* Setup default console */
984 	conmode_default();
985 	set_preferred_console();
986 
987 	apply_alternative_instructions();
988 	if (IS_ENABLED(CONFIG_EXPOLINE))
989 		nospec_init_branches();
990 
991 	/* Setup zfcp/nvme dump support */
992 	setup_zfcpdump();
993 
994 	/* Add system specific data to the random pool */
995 	setup_randomness();
996 }
997