xref: /linux/arch/s390/kernel/setup.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
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-contiguous.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 
53 #include <asm/boot_data.h>
54 #include <asm/ipl.h>
55 #include <asm/facility.h>
56 #include <asm/smp.h>
57 #include <asm/mmu_context.h>
58 #include <asm/cpcmd.h>
59 #include <asm/lowcore.h>
60 #include <asm/nmi.h>
61 #include <asm/irq.h>
62 #include <asm/page.h>
63 #include <asm/ptrace.h>
64 #include <asm/sections.h>
65 #include <asm/ebcdic.h>
66 #include <asm/diag.h>
67 #include <asm/os_info.h>
68 #include <asm/sclp.h>
69 #include <asm/stacktrace.h>
70 #include <asm/sysinfo.h>
71 #include <asm/numa.h>
72 #include <asm/alternative.h>
73 #include <asm/nospec-branch.h>
74 #include <asm/mem_detect.h>
75 #include <asm/uv.h>
76 #include "entry.h"
77 
78 /*
79  * Machine setup..
80  */
81 unsigned int console_mode = 0;
82 EXPORT_SYMBOL(console_mode);
83 
84 unsigned int console_devno = -1;
85 EXPORT_SYMBOL(console_devno);
86 
87 unsigned int console_irq = -1;
88 EXPORT_SYMBOL(console_irq);
89 
90 unsigned long elf_hwcap __read_mostly = 0;
91 char elf_platform[ELF_PLATFORM_SIZE];
92 
93 unsigned long int_hwcap = 0;
94 
95 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
96 int __bootdata_preserved(prot_virt_guest);
97 #endif
98 
99 int __bootdata(noexec_disabled);
100 int __bootdata(memory_end_set);
101 unsigned long __bootdata(memory_end);
102 unsigned long __bootdata(vmalloc_size);
103 unsigned long __bootdata(max_physmem_end);
104 struct mem_detect_info __bootdata(mem_detect);
105 
106 struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
107 struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
108 unsigned long __bootdata_preserved(__swsusp_reset_dma);
109 unsigned long __bootdata_preserved(__stext_dma);
110 unsigned long __bootdata_preserved(__etext_dma);
111 unsigned long __bootdata_preserved(__sdma);
112 unsigned long __bootdata_preserved(__edma);
113 unsigned long __bootdata_preserved(__kaslr_offset);
114 
115 unsigned long VMALLOC_START;
116 EXPORT_SYMBOL(VMALLOC_START);
117 
118 unsigned long VMALLOC_END;
119 EXPORT_SYMBOL(VMALLOC_END);
120 
121 struct page *vmemmap;
122 EXPORT_SYMBOL(vmemmap);
123 
124 unsigned long MODULES_VADDR;
125 unsigned long MODULES_END;
126 
127 /* An array with a pointer to the lowcore of every CPU. */
128 struct lowcore *lowcore_ptr[NR_CPUS];
129 EXPORT_SYMBOL(lowcore_ptr);
130 
131 /*
132  * This is set up by the setup-routine at boot-time
133  * for S390 need to find out, what we have to setup
134  * using address 0x10400 ...
135  */
136 
137 #include <asm/setup.h>
138 
139 /*
140  * condev= and conmode= setup parameter.
141  */
142 
143 static int __init condev_setup(char *str)
144 {
145 	int vdev;
146 
147 	vdev = simple_strtoul(str, &str, 0);
148 	if (vdev >= 0 && vdev < 65536) {
149 		console_devno = vdev;
150 		console_irq = -1;
151 	}
152 	return 1;
153 }
154 
155 __setup("condev=", condev_setup);
156 
157 static void __init set_preferred_console(void)
158 {
159 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
160 		add_preferred_console("ttyS", 0, NULL);
161 	else if (CONSOLE_IS_3270)
162 		add_preferred_console("tty3270", 0, NULL);
163 	else if (CONSOLE_IS_VT220)
164 		add_preferred_console("ttyS", 1, NULL);
165 	else if (CONSOLE_IS_HVC)
166 		add_preferred_console("hvc", 0, NULL);
167 }
168 
169 static int __init conmode_setup(char *str)
170 {
171 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
172 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
173                 SET_CONSOLE_SCLP;
174 #endif
175 #if defined(CONFIG_TN3215_CONSOLE)
176 	if (!strcmp(str, "3215"))
177 		SET_CONSOLE_3215;
178 #endif
179 #if defined(CONFIG_TN3270_CONSOLE)
180 	if (!strcmp(str, "3270"))
181 		SET_CONSOLE_3270;
182 #endif
183 	set_preferred_console();
184         return 1;
185 }
186 
187 __setup("conmode=", conmode_setup);
188 
189 static void __init conmode_default(void)
190 {
191 	char query_buffer[1024];
192 	char *ptr;
193 
194         if (MACHINE_IS_VM) {
195 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
196 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
197 		ptr = strstr(query_buffer, "SUBCHANNEL =");
198 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
199 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
200 		ptr = strstr(query_buffer, "CONMODE");
201 		/*
202 		 * Set the conmode to 3215 so that the device recognition
203 		 * will set the cu_type of the console to 3215. If the
204 		 * conmode is 3270 and we don't set it back then both
205 		 * 3215 and the 3270 driver will try to access the console
206 		 * device (3215 as console and 3270 as normal tty).
207 		 */
208 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
209 		if (ptr == NULL) {
210 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
211 			SET_CONSOLE_SCLP;
212 #endif
213 			return;
214 		}
215 		if (str_has_prefix(ptr + 8, "3270")) {
216 #if defined(CONFIG_TN3270_CONSOLE)
217 			SET_CONSOLE_3270;
218 #elif defined(CONFIG_TN3215_CONSOLE)
219 			SET_CONSOLE_3215;
220 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
221 			SET_CONSOLE_SCLP;
222 #endif
223 		} else if (str_has_prefix(ptr + 8, "3215")) {
224 #if defined(CONFIG_TN3215_CONSOLE)
225 			SET_CONSOLE_3215;
226 #elif defined(CONFIG_TN3270_CONSOLE)
227 			SET_CONSOLE_3270;
228 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
229 			SET_CONSOLE_SCLP;
230 #endif
231 		}
232 	} else if (MACHINE_IS_KVM) {
233 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
234 			SET_CONSOLE_VT220;
235 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
236 			SET_CONSOLE_SCLP;
237 		else
238 			SET_CONSOLE_HVC;
239 	} else {
240 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
241 		SET_CONSOLE_SCLP;
242 #endif
243 	}
244 	if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
245 		conswitchp = &dummy_con;
246 }
247 
248 #ifdef CONFIG_CRASH_DUMP
249 static void __init setup_zfcpdump(void)
250 {
251 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
252 		return;
253 	if (OLDMEM_BASE)
254 		return;
255 	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
256 	console_loglevel = 2;
257 }
258 #else
259 static inline void setup_zfcpdump(void) {}
260 #endif /* CONFIG_CRASH_DUMP */
261 
262  /*
263  * Reboot, halt and power_off stubs. They just call _machine_restart,
264  * _machine_halt or _machine_power_off.
265  */
266 
267 void machine_restart(char *command)
268 {
269 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
270 		/*
271 		 * Only unblank the console if we are called in enabled
272 		 * context or a bust_spinlocks cleared the way for us.
273 		 */
274 		console_unblank();
275 	_machine_restart(command);
276 }
277 
278 void machine_halt(void)
279 {
280 	if (!in_interrupt() || oops_in_progress)
281 		/*
282 		 * Only unblank the console if we are called in enabled
283 		 * context or a bust_spinlocks cleared the way for us.
284 		 */
285 		console_unblank();
286 	_machine_halt();
287 }
288 
289 void machine_power_off(void)
290 {
291 	if (!in_interrupt() || oops_in_progress)
292 		/*
293 		 * Only unblank the console if we are called in enabled
294 		 * context or a bust_spinlocks cleared the way for us.
295 		 */
296 		console_unblank();
297 	_machine_power_off();
298 }
299 
300 /*
301  * Dummy power off function.
302  */
303 void (*pm_power_off)(void) = machine_power_off;
304 EXPORT_SYMBOL_GPL(pm_power_off);
305 
306 void *restart_stack __section(.data);
307 
308 unsigned long stack_alloc(void)
309 {
310 #ifdef CONFIG_VMAP_STACK
311 	return (unsigned long)
312 		__vmalloc_node_range(THREAD_SIZE, THREAD_SIZE,
313 				     VMALLOC_START, VMALLOC_END,
314 				     THREADINFO_GFP,
315 				     PAGE_KERNEL, 0, NUMA_NO_NODE,
316 				     __builtin_return_address(0));
317 #else
318 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
319 #endif
320 }
321 
322 void stack_free(unsigned long stack)
323 {
324 #ifdef CONFIG_VMAP_STACK
325 	vfree((void *) stack);
326 #else
327 	free_pages(stack, THREAD_SIZE_ORDER);
328 #endif
329 }
330 
331 int __init arch_early_irq_init(void)
332 {
333 	unsigned long stack;
334 
335 	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
336 	if (!stack)
337 		panic("Couldn't allocate async stack");
338 	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
339 	return 0;
340 }
341 
342 static int __init async_stack_realloc(void)
343 {
344 	unsigned long old, new;
345 
346 	old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
347 	new = stack_alloc();
348 	if (!new)
349 		panic("Couldn't allocate async stack");
350 	S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
351 	free_pages(old, THREAD_SIZE_ORDER);
352 	return 0;
353 }
354 early_initcall(async_stack_realloc);
355 
356 void __init arch_call_rest_init(void)
357 {
358 	unsigned long stack;
359 
360 	stack = stack_alloc();
361 	if (!stack)
362 		panic("Couldn't allocate kernel stack");
363 	current->stack = (void *) stack;
364 #ifdef CONFIG_VMAP_STACK
365 	current->stack_vm_area = (void *) stack;
366 #endif
367 	set_task_stack_end_magic(current);
368 	stack += STACK_INIT_OFFSET;
369 	S390_lowcore.kernel_stack = stack;
370 	CALL_ON_STACK_NORETURN(rest_init, stack);
371 }
372 
373 static void __init setup_lowcore_dat_off(void)
374 {
375 	struct lowcore *lc;
376 
377 	/*
378 	 * Setup lowcore for boot cpu
379 	 */
380 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
381 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
382 	if (!lc)
383 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
384 		      __func__, sizeof(*lc), sizeof(*lc));
385 
386 	lc->restart_psw.mask = PSW_KERNEL_BITS;
387 	lc->restart_psw.addr = (unsigned long) restart_int_handler;
388 	lc->external_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
389 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
390 	lc->svc_new_psw.mask = PSW_KERNEL_BITS |
391 		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
392 	lc->svc_new_psw.addr = (unsigned long) system_call;
393 	lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
394 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
395 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
396 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
397 	lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
398 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
399 	lc->clock_comparator = clock_comparator_max;
400 	lc->nodat_stack = ((unsigned long) &init_thread_union)
401 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
402 	lc->current_task = (unsigned long)&init_task;
403 	lc->lpp = LPP_MAGIC;
404 	lc->machine_flags = S390_lowcore.machine_flags;
405 	lc->preempt_count = S390_lowcore.preempt_count;
406 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
407 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
408 	       sizeof(lc->stfle_fac_list));
409 	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
410 	       sizeof(lc->alt_stfle_fac_list));
411 	nmi_alloc_boot_cpu(lc);
412 	vdso_alloc_boot_cpu(lc);
413 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
414 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
415 	lc->exit_timer = S390_lowcore.exit_timer;
416 	lc->user_timer = S390_lowcore.user_timer;
417 	lc->system_timer = S390_lowcore.system_timer;
418 	lc->steal_timer = S390_lowcore.steal_timer;
419 	lc->last_update_timer = S390_lowcore.last_update_timer;
420 	lc->last_update_clock = S390_lowcore.last_update_clock;
421 
422 	/*
423 	 * Allocate the global restart stack which is the same for
424 	 * all CPUs in cast *one* of them does a PSW restart.
425 	 */
426 	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
427 	if (!restart_stack)
428 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
429 		      __func__, THREAD_SIZE, THREAD_SIZE);
430 	restart_stack += STACK_INIT_OFFSET;
431 
432 	/*
433 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
434 	 * restart data to the absolute zero lowcore. This is necessary if
435 	 * PSW restart is done on an offline CPU that has lowcore zero.
436 	 */
437 	lc->restart_stack = (unsigned long) restart_stack;
438 	lc->restart_fn = (unsigned long) do_restart;
439 	lc->restart_data = 0;
440 	lc->restart_source = -1UL;
441 
442 	/* Setup absolute zero lowcore */
443 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
444 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
445 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
446 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
447 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
448 
449 	lc->spinlock_lockval = arch_spin_lockval(0);
450 	lc->spinlock_index = 0;
451 	arch_spin_lock_setup(0);
452 	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
453 
454 	set_prefix((u32)(unsigned long) lc);
455 	lowcore_ptr[0] = lc;
456 }
457 
458 static void __init setup_lowcore_dat_on(void)
459 {
460 	__ctl_clear_bit(0, 28);
461 	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
462 	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
463 	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
464 	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
465 	__ctl_set_bit(0, 28);
466 }
467 
468 static struct resource code_resource = {
469 	.name  = "Kernel code",
470 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
471 };
472 
473 static struct resource data_resource = {
474 	.name = "Kernel data",
475 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
476 };
477 
478 static struct resource bss_resource = {
479 	.name = "Kernel bss",
480 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
481 };
482 
483 static struct resource __initdata *standard_resources[] = {
484 	&code_resource,
485 	&data_resource,
486 	&bss_resource,
487 };
488 
489 static void __init setup_resources(void)
490 {
491 	struct resource *res, *std_res, *sub_res;
492 	struct memblock_region *reg;
493 	int j;
494 
495 	code_resource.start = (unsigned long) _text;
496 	code_resource.end = (unsigned long) _etext - 1;
497 	data_resource.start = (unsigned long) _etext;
498 	data_resource.end = (unsigned long) _edata - 1;
499 	bss_resource.start = (unsigned long) __bss_start;
500 	bss_resource.end = (unsigned long) __bss_stop - 1;
501 
502 	for_each_memblock(memory, reg) {
503 		res = memblock_alloc(sizeof(*res), 8);
504 		if (!res)
505 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
506 			      __func__, sizeof(*res), 8);
507 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
508 
509 		res->name = "System RAM";
510 		res->start = reg->base;
511 		res->end = reg->base + reg->size - 1;
512 		request_resource(&iomem_resource, res);
513 
514 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
515 			std_res = standard_resources[j];
516 			if (std_res->start < res->start ||
517 			    std_res->start > res->end)
518 				continue;
519 			if (std_res->end > res->end) {
520 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
521 				if (!sub_res)
522 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
523 					      __func__, sizeof(*sub_res), 8);
524 				*sub_res = *std_res;
525 				sub_res->end = res->end;
526 				std_res->start = res->end + 1;
527 				request_resource(res, sub_res);
528 			} else {
529 				request_resource(res, std_res);
530 			}
531 		}
532 	}
533 #ifdef CONFIG_CRASH_DUMP
534 	/*
535 	 * Re-add removed crash kernel memory as reserved memory. This makes
536 	 * sure it will be mapped with the identity mapping and struct pages
537 	 * will be created, so it can be resized later on.
538 	 * However add it later since the crash kernel resource should not be
539 	 * part of the System RAM resource.
540 	 */
541 	if (crashk_res.end) {
542 		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
543 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
544 		insert_resource(&iomem_resource, &crashk_res);
545 	}
546 #endif
547 }
548 
549 static void __init setup_memory_end(void)
550 {
551 	unsigned long vmax, tmp;
552 
553 	/* Choose kernel address space layout: 3 or 4 levels. */
554 	if (IS_ENABLED(CONFIG_KASAN)) {
555 		vmax = IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)
556 			   ? _REGION1_SIZE
557 			   : _REGION2_SIZE;
558 	} else {
559 		tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
560 		tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
561 		if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
562 			vmax = _REGION2_SIZE; /* 3-level kernel page table */
563 		else
564 			vmax = _REGION1_SIZE; /* 4-level kernel page table */
565 	}
566 
567 	/* module area is at the end of the kernel address space. */
568 	MODULES_END = vmax;
569 	MODULES_VADDR = MODULES_END - MODULES_LEN;
570 	VMALLOC_END = MODULES_VADDR;
571 	VMALLOC_START = VMALLOC_END - vmalloc_size;
572 
573 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
574 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
575 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
576 	tmp = SECTION_ALIGN_UP(tmp);
577 	tmp = VMALLOC_START - tmp * sizeof(struct page);
578 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
579 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
580 	vmemmap = (struct page *) tmp;
581 
582 	/* Take care that memory_end is set and <= vmemmap */
583 	memory_end = min(memory_end ?: max_physmem_end, (unsigned long)vmemmap);
584 #ifdef CONFIG_KASAN
585 	/* fit in kasan shadow memory region between 1:1 and vmemmap */
586 	memory_end = min(memory_end, KASAN_SHADOW_START);
587 	vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
588 #endif
589 	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
590 	memblock_remove(memory_end, ULONG_MAX);
591 
592 	pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
593 }
594 
595 #ifdef CONFIG_CRASH_DUMP
596 
597 /*
598  * When kdump is enabled, we have to ensure that no memory from
599  * the area [0 - crashkernel memory size] and
600  * [crashk_res.start - crashk_res.end] is set offline.
601  */
602 static int kdump_mem_notifier(struct notifier_block *nb,
603 			      unsigned long action, void *data)
604 {
605 	struct memory_notify *arg = data;
606 
607 	if (action != MEM_GOING_OFFLINE)
608 		return NOTIFY_OK;
609 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
610 		return NOTIFY_BAD;
611 	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
612 		return NOTIFY_OK;
613 	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
614 		return NOTIFY_OK;
615 	return NOTIFY_BAD;
616 }
617 
618 static struct notifier_block kdump_mem_nb = {
619 	.notifier_call = kdump_mem_notifier,
620 };
621 
622 #endif
623 
624 /*
625  * Make sure that the area behind memory_end is protected
626  */
627 static void reserve_memory_end(void)
628 {
629 	if (memory_end_set)
630 		memblock_reserve(memory_end, ULONG_MAX);
631 }
632 
633 /*
634  * Make sure that oldmem, where the dump is stored, is protected
635  */
636 static void reserve_oldmem(void)
637 {
638 #ifdef CONFIG_CRASH_DUMP
639 	if (OLDMEM_BASE)
640 		/* Forget all memory above the running kdump system */
641 		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
642 #endif
643 }
644 
645 /*
646  * Make sure that oldmem, where the dump is stored, is protected
647  */
648 static void remove_oldmem(void)
649 {
650 #ifdef CONFIG_CRASH_DUMP
651 	if (OLDMEM_BASE)
652 		/* Forget all memory above the running kdump system */
653 		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
654 #endif
655 }
656 
657 /*
658  * Reserve memory for kdump kernel to be loaded with kexec
659  */
660 static void __init reserve_crashkernel(void)
661 {
662 #ifdef CONFIG_CRASH_DUMP
663 	unsigned long long crash_base, crash_size;
664 	phys_addr_t low, high;
665 	int rc;
666 
667 	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
668 			       &crash_base);
669 
670 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
671 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
672 	if (rc || crash_size == 0)
673 		return;
674 
675 	if (memblock.memory.regions[0].size < crash_size) {
676 		pr_info("crashkernel reservation failed: %s\n",
677 			"first memory chunk must be at least crashkernel size");
678 		return;
679 	}
680 
681 	low = crash_base ?: OLDMEM_BASE;
682 	high = low + crash_size;
683 	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
684 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
685 		crash_base = low;
686 	} else {
687 		/* Find suitable area in free memory */
688 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
689 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
690 
691 		if (crash_base && crash_base < low) {
692 			pr_info("crashkernel reservation failed: %s\n",
693 				"crash_base too low");
694 			return;
695 		}
696 		low = crash_base ?: low;
697 		crash_base = memblock_find_in_range(low, high, crash_size,
698 						    KEXEC_CRASH_MEM_ALIGN);
699 	}
700 
701 	if (!crash_base) {
702 		pr_info("crashkernel reservation failed: %s\n",
703 			"no suitable area found");
704 		return;
705 	}
706 
707 	if (register_memory_notifier(&kdump_mem_nb))
708 		return;
709 
710 	if (!OLDMEM_BASE && MACHINE_IS_VM)
711 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
712 	crashk_res.start = crash_base;
713 	crashk_res.end = crash_base + crash_size - 1;
714 	memblock_remove(crash_base, crash_size);
715 	pr_info("Reserving %lluMB of memory at %lluMB "
716 		"for crashkernel (System RAM: %luMB)\n",
717 		crash_size >> 20, crash_base >> 20,
718 		(unsigned long)memblock.memory.total_size >> 20);
719 	os_info_crashkernel_add(crash_base, crash_size);
720 #endif
721 }
722 
723 /*
724  * Reserve the initrd from being used by memblock
725  */
726 static void __init reserve_initrd(void)
727 {
728 #ifdef CONFIG_BLK_DEV_INITRD
729 	if (!INITRD_START || !INITRD_SIZE)
730 		return;
731 	initrd_start = INITRD_START;
732 	initrd_end = initrd_start + INITRD_SIZE;
733 	memblock_reserve(INITRD_START, INITRD_SIZE);
734 #endif
735 }
736 
737 /*
738  * Reserve the memory area used to pass the certificate lists
739  */
740 static void __init reserve_certificate_list(void)
741 {
742 	if (ipl_cert_list_addr)
743 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
744 }
745 
746 static void __init reserve_mem_detect_info(void)
747 {
748 	unsigned long start, size;
749 
750 	get_mem_detect_reserved(&start, &size);
751 	if (size)
752 		memblock_reserve(start, size);
753 }
754 
755 static void __init free_mem_detect_info(void)
756 {
757 	unsigned long start, size;
758 
759 	get_mem_detect_reserved(&start, &size);
760 	if (size)
761 		memblock_free(start, size);
762 }
763 
764 static void __init memblock_physmem_add(phys_addr_t start, phys_addr_t size)
765 {
766 	memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
767 		     start, start + size - 1);
768 	memblock_add_range(&memblock.memory, start, size, 0, 0);
769 	memblock_add_range(&memblock.physmem, start, size, 0, 0);
770 }
771 
772 static const char * __init get_mem_info_source(void)
773 {
774 	switch (mem_detect.info_source) {
775 	case MEM_DETECT_SCLP_STOR_INFO:
776 		return "sclp storage info";
777 	case MEM_DETECT_DIAG260:
778 		return "diag260";
779 	case MEM_DETECT_SCLP_READ_INFO:
780 		return "sclp read info";
781 	case MEM_DETECT_BIN_SEARCH:
782 		return "binary search";
783 	}
784 	return "none";
785 }
786 
787 static void __init memblock_add_mem_detect_info(void)
788 {
789 	unsigned long start, end;
790 	int i;
791 
792 	memblock_dbg("physmem info source: %s (%hhd)\n",
793 		     get_mem_info_source(), mem_detect.info_source);
794 	/* keep memblock lists close to the kernel */
795 	memblock_set_bottom_up(true);
796 	for_each_mem_detect_block(i, &start, &end)
797 		memblock_physmem_add(start, end - start);
798 	memblock_set_bottom_up(false);
799 	memblock_dump_all();
800 }
801 
802 /*
803  * Check for initrd being in usable memory
804  */
805 static void __init check_initrd(void)
806 {
807 #ifdef CONFIG_BLK_DEV_INITRD
808 	if (INITRD_START && INITRD_SIZE &&
809 	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
810 		pr_err("The initial RAM disk does not fit into the memory\n");
811 		memblock_free(INITRD_START, INITRD_SIZE);
812 		initrd_start = initrd_end = 0;
813 	}
814 #endif
815 }
816 
817 /*
818  * Reserve memory used for lowcore/command line/kernel image.
819  */
820 static void __init reserve_kernel(void)
821 {
822 	unsigned long start_pfn = PFN_UP(__pa(_end));
823 
824 	memblock_reserve(0, HEAD_END);
825 	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
826 			 - (unsigned long)_stext);
827 	memblock_reserve(__sdma, __edma - __sdma);
828 }
829 
830 static void __init setup_memory(void)
831 {
832 	struct memblock_region *reg;
833 
834 	/*
835 	 * Init storage key for present memory
836 	 */
837 	for_each_memblock(memory, reg) {
838 		storage_key_init_range(reg->base, reg->base + reg->size);
839 	}
840 	psw_set_key(PAGE_DEFAULT_KEY);
841 
842 	/* Only cosmetics */
843 	memblock_enforce_memory_limit(memblock_end_of_DRAM());
844 }
845 
846 /*
847  * Setup hardware capabilities.
848  */
849 static int __init setup_hwcaps(void)
850 {
851 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
852 	struct cpuid cpu_id;
853 	int i;
854 
855 	/*
856 	 * The store facility list bits numbers as found in the principles
857 	 * of operation are numbered with bit 1UL<<31 as number 0 to
858 	 * bit 1UL<<0 as number 31.
859 	 *   Bit 0: instructions named N3, "backported" to esa-mode
860 	 *   Bit 2: z/Architecture mode is active
861 	 *   Bit 7: the store-facility-list-extended facility is installed
862 	 *   Bit 17: the message-security assist is installed
863 	 *   Bit 19: the long-displacement facility is installed
864 	 *   Bit 21: the extended-immediate facility is installed
865 	 *   Bit 22: extended-translation facility 3 is installed
866 	 *   Bit 30: extended-translation facility 3 enhancement facility
867 	 * These get translated to:
868 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
869 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
870 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
871 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
872 	 */
873 	for (i = 0; i < 6; i++)
874 		if (test_facility(stfl_bits[i]))
875 			elf_hwcap |= 1UL << i;
876 
877 	if (test_facility(22) && test_facility(30))
878 		elf_hwcap |= HWCAP_S390_ETF3EH;
879 
880 	/*
881 	 * Check for additional facilities with store-facility-list-extended.
882 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
883 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
884 	 * as stored by stfl, bits 32-xxx contain additional facilities.
885 	 * How many facility words are stored depends on the number of
886 	 * doublewords passed to the instruction. The additional facilities
887 	 * are:
888 	 *   Bit 42: decimal floating point facility is installed
889 	 *   Bit 44: perform floating point operation facility is installed
890 	 * translated to:
891 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
892 	 */
893 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
894 		elf_hwcap |= HWCAP_S390_DFP;
895 
896 	/*
897 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
898 	 */
899 	if (MACHINE_HAS_EDAT1)
900 		elf_hwcap |= HWCAP_S390_HPAGE;
901 
902 	/*
903 	 * 64-bit register support for 31-bit processes
904 	 * HWCAP_S390_HIGH_GPRS is bit 9.
905 	 */
906 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
907 
908 	/*
909 	 * Transactional execution support HWCAP_S390_TE is bit 10.
910 	 */
911 	if (MACHINE_HAS_TE)
912 		elf_hwcap |= HWCAP_S390_TE;
913 
914 	/*
915 	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
916 	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
917 	 * instead of facility bit 129.
918 	 */
919 	if (MACHINE_HAS_VX) {
920 		elf_hwcap |= HWCAP_S390_VXRS;
921 		if (test_facility(134))
922 			elf_hwcap |= HWCAP_S390_VXRS_EXT;
923 		if (test_facility(135))
924 			elf_hwcap |= HWCAP_S390_VXRS_BCD;
925 		if (test_facility(148))
926 			elf_hwcap |= HWCAP_S390_VXRS_EXT2;
927 		if (test_facility(152))
928 			elf_hwcap |= HWCAP_S390_VXRS_PDE;
929 	}
930 	if (test_facility(150))
931 		elf_hwcap |= HWCAP_S390_SORT;
932 	if (test_facility(151))
933 		elf_hwcap |= HWCAP_S390_DFLT;
934 
935 	/*
936 	 * Guarded storage support HWCAP_S390_GS is bit 12.
937 	 */
938 	if (MACHINE_HAS_GS)
939 		elf_hwcap |= HWCAP_S390_GS;
940 
941 	get_cpu_id(&cpu_id);
942 	add_device_randomness(&cpu_id, sizeof(cpu_id));
943 	switch (cpu_id.machine) {
944 	case 0x2064:
945 	case 0x2066:
946 	default:	/* Use "z900" as default for 64 bit kernels. */
947 		strcpy(elf_platform, "z900");
948 		break;
949 	case 0x2084:
950 	case 0x2086:
951 		strcpy(elf_platform, "z990");
952 		break;
953 	case 0x2094:
954 	case 0x2096:
955 		strcpy(elf_platform, "z9-109");
956 		break;
957 	case 0x2097:
958 	case 0x2098:
959 		strcpy(elf_platform, "z10");
960 		break;
961 	case 0x2817:
962 	case 0x2818:
963 		strcpy(elf_platform, "z196");
964 		break;
965 	case 0x2827:
966 	case 0x2828:
967 		strcpy(elf_platform, "zEC12");
968 		break;
969 	case 0x2964:
970 	case 0x2965:
971 		strcpy(elf_platform, "z13");
972 		break;
973 	case 0x3906:
974 	case 0x3907:
975 		strcpy(elf_platform, "z14");
976 		break;
977 	case 0x8561:
978 	case 0x8562:
979 		strcpy(elf_platform, "z15");
980 		break;
981 	}
982 
983 	/*
984 	 * Virtualization support HWCAP_INT_SIE is bit 0.
985 	 */
986 	if (sclp.has_sief2)
987 		int_hwcap |= HWCAP_INT_SIE;
988 
989 	return 0;
990 }
991 arch_initcall(setup_hwcaps);
992 
993 /*
994  * Add system information as device randomness
995  */
996 static void __init setup_randomness(void)
997 {
998 	struct sysinfo_3_2_2 *vmms;
999 
1000 	vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
1001 							    PAGE_SIZE);
1002 	if (!vmms)
1003 		panic("Failed to allocate memory for sysinfo structure\n");
1004 
1005 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
1006 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
1007 	memblock_free((unsigned long) vmms, PAGE_SIZE);
1008 }
1009 
1010 /*
1011  * Find the correct size for the task_struct. This depends on
1012  * the size of the struct fpu at the end of the thread_struct
1013  * which is embedded in the task_struct.
1014  */
1015 static void __init setup_task_size(void)
1016 {
1017 	int task_size = sizeof(struct task_struct);
1018 
1019 	if (!MACHINE_HAS_VX) {
1020 		task_size -= sizeof(__vector128) * __NUM_VXRS;
1021 		task_size += sizeof(freg_t) * __NUM_FPRS;
1022 	}
1023 	arch_task_struct_size = task_size;
1024 }
1025 
1026 /*
1027  * Issue diagnose 318 to set the control program name and
1028  * version codes.
1029  */
1030 static void __init setup_control_program_code(void)
1031 {
1032 	union diag318_info diag318_info = {
1033 		.cpnc = CPNC_LINUX,
1034 		.cpvc_linux = 0,
1035 		.cpvc_distro = {0},
1036 	};
1037 
1038 	if (!sclp.has_diag318)
1039 		return;
1040 
1041 	diag_stat_inc(DIAG_STAT_X318);
1042 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1043 }
1044 
1045 /*
1046  * Print the component list from the IPL report
1047  */
1048 static void __init log_component_list(void)
1049 {
1050 	struct ipl_rb_component_entry *ptr, *end;
1051 	char *str;
1052 
1053 	if (!early_ipl_comp_list_addr)
1054 		return;
1055 	if (ipl_block.hdr.flags & IPL_PL_FLAG_IPLSR)
1056 		pr_info("Linux is running with Secure-IPL enabled\n");
1057 	else
1058 		pr_info("Linux is running with Secure-IPL disabled\n");
1059 	ptr = (void *) early_ipl_comp_list_addr;
1060 	end = (void *) ptr + early_ipl_comp_list_size;
1061 	pr_info("The IPL report contains the following components:\n");
1062 	while (ptr < end) {
1063 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
1064 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
1065 				str = "signed, verified";
1066 			else
1067 				str = "signed, verification failed";
1068 		} else {
1069 			str = "not signed";
1070 		}
1071 		pr_info("%016llx - %016llx (%s)\n",
1072 			ptr->addr, ptr->addr + ptr->len, str);
1073 		ptr++;
1074 	}
1075 }
1076 
1077 /*
1078  * Setup function called from init/main.c just after the banner
1079  * was printed.
1080  */
1081 
1082 void __init setup_arch(char **cmdline_p)
1083 {
1084         /*
1085          * print what head.S has found out about the machine
1086          */
1087 	if (MACHINE_IS_VM)
1088 		pr_info("Linux is running as a z/VM "
1089 			"guest operating system in 64-bit mode\n");
1090 	else if (MACHINE_IS_KVM)
1091 		pr_info("Linux is running under KVM in 64-bit mode\n");
1092 	else if (MACHINE_IS_LPAR)
1093 		pr_info("Linux is running natively in 64-bit mode\n");
1094 	else
1095 		pr_info("Linux is running as a guest in 64-bit mode\n");
1096 
1097 	log_component_list();
1098 
1099 	/* Have one command line that is parsed and saved in /proc/cmdline */
1100 	/* boot_command_line has been already set up in early.c */
1101 	*cmdline_p = boot_command_line;
1102 
1103         ROOT_DEV = Root_RAM0;
1104 
1105 	init_mm.start_code = (unsigned long) _text;
1106 	init_mm.end_code = (unsigned long) _etext;
1107 	init_mm.end_data = (unsigned long) _edata;
1108 	init_mm.brk = (unsigned long) _end;
1109 
1110 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1111 		nospec_auto_detect();
1112 
1113 	parse_early_param();
1114 #ifdef CONFIG_CRASH_DUMP
1115 	/* Deactivate elfcorehdr= kernel parameter */
1116 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
1117 #endif
1118 
1119 	os_info_init();
1120 	setup_ipl();
1121 	setup_task_size();
1122 	setup_control_program_code();
1123 
1124 	/* Do some memory reservations *before* memory is added to memblock */
1125 	reserve_memory_end();
1126 	reserve_oldmem();
1127 	reserve_kernel();
1128 	reserve_initrd();
1129 	reserve_certificate_list();
1130 	reserve_mem_detect_info();
1131 	memblock_allow_resize();
1132 
1133 	/* Get information about *all* installed memory */
1134 	memblock_add_mem_detect_info();
1135 
1136 	free_mem_detect_info();
1137 	remove_oldmem();
1138 
1139 	/*
1140 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
1141 	 * extra checks that HOLES_IN_ZONE would require.
1142 	 *
1143 	 * Is this still required?
1144 	 */
1145 	memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
1146 
1147 	setup_memory_end();
1148 	setup_memory();
1149 	dma_contiguous_reserve(memory_end);
1150 	vmcp_cma_reserve();
1151 
1152 	check_initrd();
1153 	reserve_crashkernel();
1154 #ifdef CONFIG_CRASH_DUMP
1155 	/*
1156 	 * Be aware that smp_save_dump_cpus() triggers a system reset.
1157 	 * Therefore CPU and device initialization should be done afterwards.
1158 	 */
1159 	smp_save_dump_cpus();
1160 #endif
1161 
1162 	setup_resources();
1163 	setup_lowcore_dat_off();
1164 	smp_fill_possible_mask();
1165 	cpu_detect_mhz_feature();
1166         cpu_init();
1167 	numa_setup();
1168 	smp_detect_cpus();
1169 	topology_init_early();
1170 
1171 	/*
1172 	 * Create kernel page tables and switch to virtual addressing.
1173 	 */
1174         paging_init();
1175 
1176 	/*
1177 	 * After paging_init created the kernel page table, the new PSWs
1178 	 * in lowcore can now run with DAT enabled.
1179 	 */
1180 	setup_lowcore_dat_on();
1181 
1182         /* Setup default console */
1183 	conmode_default();
1184 	set_preferred_console();
1185 
1186 	apply_alternative_instructions();
1187 	if (IS_ENABLED(CONFIG_EXPOLINE))
1188 		nospec_init_branches();
1189 
1190 	/* Setup zfcpdump support */
1191 	setup_zfcpdump();
1192 
1193 	/* Add system specific data to the random pool */
1194 	setup_randomness();
1195 }
1196