xref: /openbmc/linux/arch/s390/kernel/setup.c (revision 015d239a)
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 unsigned int __bootdata_preserved(zlib_dfltcc_support);
115 EXPORT_SYMBOL(zlib_dfltcc_support);
116 
117 unsigned long VMALLOC_START;
118 EXPORT_SYMBOL(VMALLOC_START);
119 
120 unsigned long VMALLOC_END;
121 EXPORT_SYMBOL(VMALLOC_END);
122 
123 struct page *vmemmap;
124 EXPORT_SYMBOL(vmemmap);
125 
126 unsigned long MODULES_VADDR;
127 unsigned long MODULES_END;
128 
129 /* An array with a pointer to the lowcore of every CPU. */
130 struct lowcore *lowcore_ptr[NR_CPUS];
131 EXPORT_SYMBOL(lowcore_ptr);
132 
133 /*
134  * This is set up by the setup-routine at boot-time
135  * for S390 need to find out, what we have to setup
136  * using address 0x10400 ...
137  */
138 
139 #include <asm/setup.h>
140 
141 /*
142  * condev= and conmode= setup parameter.
143  */
144 
145 static int __init condev_setup(char *str)
146 {
147 	int vdev;
148 
149 	vdev = simple_strtoul(str, &str, 0);
150 	if (vdev >= 0 && vdev < 65536) {
151 		console_devno = vdev;
152 		console_irq = -1;
153 	}
154 	return 1;
155 }
156 
157 __setup("condev=", condev_setup);
158 
159 static void __init set_preferred_console(void)
160 {
161 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
162 		add_preferred_console("ttyS", 0, NULL);
163 	else if (CONSOLE_IS_3270)
164 		add_preferred_console("tty3270", 0, NULL);
165 	else if (CONSOLE_IS_VT220)
166 		add_preferred_console("ttyS", 1, NULL);
167 	else if (CONSOLE_IS_HVC)
168 		add_preferred_console("hvc", 0, NULL);
169 }
170 
171 static int __init conmode_setup(char *str)
172 {
173 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
174 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
175                 SET_CONSOLE_SCLP;
176 #endif
177 #if defined(CONFIG_TN3215_CONSOLE)
178 	if (!strcmp(str, "3215"))
179 		SET_CONSOLE_3215;
180 #endif
181 #if defined(CONFIG_TN3270_CONSOLE)
182 	if (!strcmp(str, "3270"))
183 		SET_CONSOLE_3270;
184 #endif
185 	set_preferred_console();
186         return 1;
187 }
188 
189 __setup("conmode=", conmode_setup);
190 
191 static void __init conmode_default(void)
192 {
193 	char query_buffer[1024];
194 	char *ptr;
195 
196         if (MACHINE_IS_VM) {
197 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
198 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
199 		ptr = strstr(query_buffer, "SUBCHANNEL =");
200 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
201 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
202 		ptr = strstr(query_buffer, "CONMODE");
203 		/*
204 		 * Set the conmode to 3215 so that the device recognition
205 		 * will set the cu_type of the console to 3215. If the
206 		 * conmode is 3270 and we don't set it back then both
207 		 * 3215 and the 3270 driver will try to access the console
208 		 * device (3215 as console and 3270 as normal tty).
209 		 */
210 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
211 		if (ptr == NULL) {
212 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
213 			SET_CONSOLE_SCLP;
214 #endif
215 			return;
216 		}
217 		if (str_has_prefix(ptr + 8, "3270")) {
218 #if defined(CONFIG_TN3270_CONSOLE)
219 			SET_CONSOLE_3270;
220 #elif defined(CONFIG_TN3215_CONSOLE)
221 			SET_CONSOLE_3215;
222 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
223 			SET_CONSOLE_SCLP;
224 #endif
225 		} else if (str_has_prefix(ptr + 8, "3215")) {
226 #if defined(CONFIG_TN3215_CONSOLE)
227 			SET_CONSOLE_3215;
228 #elif defined(CONFIG_TN3270_CONSOLE)
229 			SET_CONSOLE_3270;
230 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
231 			SET_CONSOLE_SCLP;
232 #endif
233 		}
234 	} else if (MACHINE_IS_KVM) {
235 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
236 			SET_CONSOLE_VT220;
237 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
238 			SET_CONSOLE_SCLP;
239 		else
240 			SET_CONSOLE_HVC;
241 	} else {
242 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
243 		SET_CONSOLE_SCLP;
244 #endif
245 	}
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 const char * __init get_mem_info_source(void)
765 {
766 	switch (mem_detect.info_source) {
767 	case MEM_DETECT_SCLP_STOR_INFO:
768 		return "sclp storage info";
769 	case MEM_DETECT_DIAG260:
770 		return "diag260";
771 	case MEM_DETECT_SCLP_READ_INFO:
772 		return "sclp read info";
773 	case MEM_DETECT_BIN_SEARCH:
774 		return "binary search";
775 	}
776 	return "none";
777 }
778 
779 static void __init memblock_add_mem_detect_info(void)
780 {
781 	unsigned long start, end;
782 	int i;
783 
784 	memblock_dbg("physmem info source: %s (%hhd)\n",
785 		     get_mem_info_source(), mem_detect.info_source);
786 	/* keep memblock lists close to the kernel */
787 	memblock_set_bottom_up(true);
788 	for_each_mem_detect_block(i, &start, &end) {
789 		memblock_add(start, end - start);
790 		memblock_physmem_add(start, end - start);
791 	}
792 	memblock_set_bottom_up(false);
793 	memblock_dump_all();
794 }
795 
796 /*
797  * Check for initrd being in usable memory
798  */
799 static void __init check_initrd(void)
800 {
801 #ifdef CONFIG_BLK_DEV_INITRD
802 	if (INITRD_START && INITRD_SIZE &&
803 	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
804 		pr_err("The initial RAM disk does not fit into the memory\n");
805 		memblock_free(INITRD_START, INITRD_SIZE);
806 		initrd_start = initrd_end = 0;
807 	}
808 #endif
809 }
810 
811 /*
812  * Reserve memory used for lowcore/command line/kernel image.
813  */
814 static void __init reserve_kernel(void)
815 {
816 	unsigned long start_pfn = PFN_UP(__pa(_end));
817 
818 	memblock_reserve(0, HEAD_END);
819 	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
820 			 - (unsigned long)_stext);
821 	memblock_reserve(__sdma, __edma - __sdma);
822 }
823 
824 static void __init setup_memory(void)
825 {
826 	struct memblock_region *reg;
827 
828 	/*
829 	 * Init storage key for present memory
830 	 */
831 	for_each_memblock(memory, reg) {
832 		storage_key_init_range(reg->base, reg->base + reg->size);
833 	}
834 	psw_set_key(PAGE_DEFAULT_KEY);
835 
836 	/* Only cosmetics */
837 	memblock_enforce_memory_limit(memblock_end_of_DRAM());
838 }
839 
840 /*
841  * Setup hardware capabilities.
842  */
843 static int __init setup_hwcaps(void)
844 {
845 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
846 	struct cpuid cpu_id;
847 	int i;
848 
849 	/*
850 	 * The store facility list bits numbers as found in the principles
851 	 * of operation are numbered with bit 1UL<<31 as number 0 to
852 	 * bit 1UL<<0 as number 31.
853 	 *   Bit 0: instructions named N3, "backported" to esa-mode
854 	 *   Bit 2: z/Architecture mode is active
855 	 *   Bit 7: the store-facility-list-extended facility is installed
856 	 *   Bit 17: the message-security assist is installed
857 	 *   Bit 19: the long-displacement facility is installed
858 	 *   Bit 21: the extended-immediate facility is installed
859 	 *   Bit 22: extended-translation facility 3 is installed
860 	 *   Bit 30: extended-translation facility 3 enhancement facility
861 	 * These get translated to:
862 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
863 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
864 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
865 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
866 	 */
867 	for (i = 0; i < 6; i++)
868 		if (test_facility(stfl_bits[i]))
869 			elf_hwcap |= 1UL << i;
870 
871 	if (test_facility(22) && test_facility(30))
872 		elf_hwcap |= HWCAP_S390_ETF3EH;
873 
874 	/*
875 	 * Check for additional facilities with store-facility-list-extended.
876 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
877 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
878 	 * as stored by stfl, bits 32-xxx contain additional facilities.
879 	 * How many facility words are stored depends on the number of
880 	 * doublewords passed to the instruction. The additional facilities
881 	 * are:
882 	 *   Bit 42: decimal floating point facility is installed
883 	 *   Bit 44: perform floating point operation facility is installed
884 	 * translated to:
885 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
886 	 */
887 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
888 		elf_hwcap |= HWCAP_S390_DFP;
889 
890 	/*
891 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
892 	 */
893 	if (MACHINE_HAS_EDAT1)
894 		elf_hwcap |= HWCAP_S390_HPAGE;
895 
896 	/*
897 	 * 64-bit register support for 31-bit processes
898 	 * HWCAP_S390_HIGH_GPRS is bit 9.
899 	 */
900 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
901 
902 	/*
903 	 * Transactional execution support HWCAP_S390_TE is bit 10.
904 	 */
905 	if (MACHINE_HAS_TE)
906 		elf_hwcap |= HWCAP_S390_TE;
907 
908 	/*
909 	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
910 	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
911 	 * instead of facility bit 129.
912 	 */
913 	if (MACHINE_HAS_VX) {
914 		elf_hwcap |= HWCAP_S390_VXRS;
915 		if (test_facility(134))
916 			elf_hwcap |= HWCAP_S390_VXRS_EXT;
917 		if (test_facility(135))
918 			elf_hwcap |= HWCAP_S390_VXRS_BCD;
919 		if (test_facility(148))
920 			elf_hwcap |= HWCAP_S390_VXRS_EXT2;
921 		if (test_facility(152))
922 			elf_hwcap |= HWCAP_S390_VXRS_PDE;
923 	}
924 	if (test_facility(150))
925 		elf_hwcap |= HWCAP_S390_SORT;
926 	if (test_facility(151))
927 		elf_hwcap |= HWCAP_S390_DFLT;
928 
929 	/*
930 	 * Guarded storage support HWCAP_S390_GS is bit 12.
931 	 */
932 	if (MACHINE_HAS_GS)
933 		elf_hwcap |= HWCAP_S390_GS;
934 
935 	get_cpu_id(&cpu_id);
936 	add_device_randomness(&cpu_id, sizeof(cpu_id));
937 	switch (cpu_id.machine) {
938 	case 0x2064:
939 	case 0x2066:
940 	default:	/* Use "z900" as default for 64 bit kernels. */
941 		strcpy(elf_platform, "z900");
942 		break;
943 	case 0x2084:
944 	case 0x2086:
945 		strcpy(elf_platform, "z990");
946 		break;
947 	case 0x2094:
948 	case 0x2096:
949 		strcpy(elf_platform, "z9-109");
950 		break;
951 	case 0x2097:
952 	case 0x2098:
953 		strcpy(elf_platform, "z10");
954 		break;
955 	case 0x2817:
956 	case 0x2818:
957 		strcpy(elf_platform, "z196");
958 		break;
959 	case 0x2827:
960 	case 0x2828:
961 		strcpy(elf_platform, "zEC12");
962 		break;
963 	case 0x2964:
964 	case 0x2965:
965 		strcpy(elf_platform, "z13");
966 		break;
967 	case 0x3906:
968 	case 0x3907:
969 		strcpy(elf_platform, "z14");
970 		break;
971 	case 0x8561:
972 	case 0x8562:
973 		strcpy(elf_platform, "z15");
974 		break;
975 	}
976 
977 	/*
978 	 * Virtualization support HWCAP_INT_SIE is bit 0.
979 	 */
980 	if (sclp.has_sief2)
981 		int_hwcap |= HWCAP_INT_SIE;
982 
983 	return 0;
984 }
985 arch_initcall(setup_hwcaps);
986 
987 /*
988  * Add system information as device randomness
989  */
990 static void __init setup_randomness(void)
991 {
992 	struct sysinfo_3_2_2 *vmms;
993 
994 	vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
995 							    PAGE_SIZE);
996 	if (!vmms)
997 		panic("Failed to allocate memory for sysinfo structure\n");
998 
999 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
1000 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
1001 	memblock_free((unsigned long) vmms, PAGE_SIZE);
1002 }
1003 
1004 /*
1005  * Find the correct size for the task_struct. This depends on
1006  * the size of the struct fpu at the end of the thread_struct
1007  * which is embedded in the task_struct.
1008  */
1009 static void __init setup_task_size(void)
1010 {
1011 	int task_size = sizeof(struct task_struct);
1012 
1013 	if (!MACHINE_HAS_VX) {
1014 		task_size -= sizeof(__vector128) * __NUM_VXRS;
1015 		task_size += sizeof(freg_t) * __NUM_FPRS;
1016 	}
1017 	arch_task_struct_size = task_size;
1018 }
1019 
1020 /*
1021  * Issue diagnose 318 to set the control program name and
1022  * version codes.
1023  */
1024 static void __init setup_control_program_code(void)
1025 {
1026 	union diag318_info diag318_info = {
1027 		.cpnc = CPNC_LINUX,
1028 		.cpvc_linux = 0,
1029 		.cpvc_distro = {0},
1030 	};
1031 
1032 	if (!sclp.has_diag318)
1033 		return;
1034 
1035 	diag_stat_inc(DIAG_STAT_X318);
1036 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1037 }
1038 
1039 /*
1040  * Print the component list from the IPL report
1041  */
1042 static void __init log_component_list(void)
1043 {
1044 	struct ipl_rb_component_entry *ptr, *end;
1045 	char *str;
1046 
1047 	if (!early_ipl_comp_list_addr)
1048 		return;
1049 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
1050 		pr_info("Linux is running with Secure-IPL enabled\n");
1051 	else
1052 		pr_info("Linux is running with Secure-IPL disabled\n");
1053 	ptr = (void *) early_ipl_comp_list_addr;
1054 	end = (void *) ptr + early_ipl_comp_list_size;
1055 	pr_info("The IPL report contains the following components:\n");
1056 	while (ptr < end) {
1057 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
1058 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
1059 				str = "signed, verified";
1060 			else
1061 				str = "signed, verification failed";
1062 		} else {
1063 			str = "not signed";
1064 		}
1065 		pr_info("%016llx - %016llx (%s)\n",
1066 			ptr->addr, ptr->addr + ptr->len, str);
1067 		ptr++;
1068 	}
1069 }
1070 
1071 /*
1072  * Setup function called from init/main.c just after the banner
1073  * was printed.
1074  */
1075 
1076 void __init setup_arch(char **cmdline_p)
1077 {
1078         /*
1079          * print what head.S has found out about the machine
1080          */
1081 	if (MACHINE_IS_VM)
1082 		pr_info("Linux is running as a z/VM "
1083 			"guest operating system in 64-bit mode\n");
1084 	else if (MACHINE_IS_KVM)
1085 		pr_info("Linux is running under KVM in 64-bit mode\n");
1086 	else if (MACHINE_IS_LPAR)
1087 		pr_info("Linux is running natively in 64-bit mode\n");
1088 	else
1089 		pr_info("Linux is running as a guest in 64-bit mode\n");
1090 
1091 	log_component_list();
1092 
1093 	/* Have one command line that is parsed and saved in /proc/cmdline */
1094 	/* boot_command_line has been already set up in early.c */
1095 	*cmdline_p = boot_command_line;
1096 
1097         ROOT_DEV = Root_RAM0;
1098 
1099 	init_mm.start_code = (unsigned long) _text;
1100 	init_mm.end_code = (unsigned long) _etext;
1101 	init_mm.end_data = (unsigned long) _edata;
1102 	init_mm.brk = (unsigned long) _end;
1103 
1104 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1105 		nospec_auto_detect();
1106 
1107 	parse_early_param();
1108 #ifdef CONFIG_CRASH_DUMP
1109 	/* Deactivate elfcorehdr= kernel parameter */
1110 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
1111 #endif
1112 
1113 	os_info_init();
1114 	setup_ipl();
1115 	setup_task_size();
1116 	setup_control_program_code();
1117 
1118 	/* Do some memory reservations *before* memory is added to memblock */
1119 	reserve_memory_end();
1120 	reserve_oldmem();
1121 	reserve_kernel();
1122 	reserve_initrd();
1123 	reserve_certificate_list();
1124 	reserve_mem_detect_info();
1125 	memblock_allow_resize();
1126 
1127 	/* Get information about *all* installed memory */
1128 	memblock_add_mem_detect_info();
1129 
1130 	free_mem_detect_info();
1131 	remove_oldmem();
1132 
1133 	/*
1134 	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
1135 	 * extra checks that HOLES_IN_ZONE would require.
1136 	 *
1137 	 * Is this still required?
1138 	 */
1139 	memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
1140 
1141 	setup_memory_end();
1142 	setup_memory();
1143 	dma_contiguous_reserve(memory_end);
1144 	vmcp_cma_reserve();
1145 
1146 	check_initrd();
1147 	reserve_crashkernel();
1148 #ifdef CONFIG_CRASH_DUMP
1149 	/*
1150 	 * Be aware that smp_save_dump_cpus() triggers a system reset.
1151 	 * Therefore CPU and device initialization should be done afterwards.
1152 	 */
1153 	smp_save_dump_cpus();
1154 #endif
1155 
1156 	setup_resources();
1157 	setup_lowcore_dat_off();
1158 	smp_fill_possible_mask();
1159 	cpu_detect_mhz_feature();
1160         cpu_init();
1161 	numa_setup();
1162 	smp_detect_cpus();
1163 	topology_init_early();
1164 
1165 	/*
1166 	 * Create kernel page tables and switch to virtual addressing.
1167 	 */
1168         paging_init();
1169 
1170 	/*
1171 	 * After paging_init created the kernel page table, the new PSWs
1172 	 * in lowcore can now run with DAT enabled.
1173 	 */
1174 	setup_lowcore_dat_on();
1175 
1176         /* Setup default console */
1177 	conmode_default();
1178 	set_preferred_console();
1179 
1180 	apply_alternative_instructions();
1181 	if (IS_ENABLED(CONFIG_EXPOLINE))
1182 		nospec_init_branches();
1183 
1184 	/* Setup zfcpdump support */
1185 	setup_zfcpdump();
1186 
1187 	/* Add system specific data to the random pool */
1188 	setup_randomness();
1189 }
1190