xref: /openbmc/linux/arch/s390/kernel/setup.c (revision cff11abeca78aa782378401ca2800bd2194aa14e)
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 <asm/asm-offsets.h>
77 #include "entry.h"
78 
79 /*
80  * Machine setup..
81  */
82 unsigned int console_mode = 0;
83 EXPORT_SYMBOL(console_mode);
84 
85 unsigned int console_devno = -1;
86 EXPORT_SYMBOL(console_devno);
87 
88 unsigned int console_irq = -1;
89 EXPORT_SYMBOL(console_irq);
90 
91 unsigned long elf_hwcap __read_mostly = 0;
92 char elf_platform[ELF_PLATFORM_SIZE];
93 
94 unsigned long int_hwcap = 0;
95 
96 int __bootdata(noexec_disabled);
97 int __bootdata(memory_end_set);
98 unsigned long __bootdata(memory_end);
99 unsigned long __bootdata(vmalloc_size);
100 unsigned long __bootdata(max_physmem_end);
101 struct mem_detect_info __bootdata(mem_detect);
102 
103 struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
104 struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
105 unsigned long __bootdata_preserved(__swsusp_reset_dma);
106 unsigned long __bootdata_preserved(__stext_dma);
107 unsigned long __bootdata_preserved(__etext_dma);
108 unsigned long __bootdata_preserved(__sdma);
109 unsigned long __bootdata_preserved(__edma);
110 unsigned long __bootdata_preserved(__kaslr_offset);
111 unsigned int __bootdata_preserved(zlib_dfltcc_support);
112 EXPORT_SYMBOL(zlib_dfltcc_support);
113 
114 unsigned long VMALLOC_START;
115 EXPORT_SYMBOL(VMALLOC_START);
116 
117 unsigned long VMALLOC_END;
118 EXPORT_SYMBOL(VMALLOC_END);
119 
120 struct page *vmemmap;
121 EXPORT_SYMBOL(vmemmap);
122 
123 unsigned long MODULES_VADDR;
124 unsigned long MODULES_END;
125 
126 /* An array with a pointer to the lowcore of every CPU. */
127 struct lowcore *lowcore_ptr[NR_CPUS];
128 EXPORT_SYMBOL(lowcore_ptr);
129 
130 /*
131  * This is set up by the setup-routine at boot-time
132  * for S390 need to find out, what we have to setup
133  * using address 0x10400 ...
134  */
135 
136 #include <asm/setup.h>
137 
138 /*
139  * condev= and conmode= setup parameter.
140  */
141 
142 static int __init condev_setup(char *str)
143 {
144 	int vdev;
145 
146 	vdev = simple_strtoul(str, &str, 0);
147 	if (vdev >= 0 && vdev < 65536) {
148 		console_devno = vdev;
149 		console_irq = -1;
150 	}
151 	return 1;
152 }
153 
154 __setup("condev=", condev_setup);
155 
156 static void __init set_preferred_console(void)
157 {
158 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
159 		add_preferred_console("ttyS", 0, NULL);
160 	else if (CONSOLE_IS_3270)
161 		add_preferred_console("tty3270", 0, NULL);
162 	else if (CONSOLE_IS_VT220)
163 		add_preferred_console("ttyS", 1, NULL);
164 	else if (CONSOLE_IS_HVC)
165 		add_preferred_console("hvc", 0, NULL);
166 }
167 
168 static int __init conmode_setup(char *str)
169 {
170 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
171 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
172                 SET_CONSOLE_SCLP;
173 #endif
174 #if defined(CONFIG_TN3215_CONSOLE)
175 	if (!strcmp(str, "3215"))
176 		SET_CONSOLE_3215;
177 #endif
178 #if defined(CONFIG_TN3270_CONSOLE)
179 	if (!strcmp(str, "3270"))
180 		SET_CONSOLE_3270;
181 #endif
182 	set_preferred_console();
183         return 1;
184 }
185 
186 __setup("conmode=", conmode_setup);
187 
188 static void __init conmode_default(void)
189 {
190 	char query_buffer[1024];
191 	char *ptr;
192 
193         if (MACHINE_IS_VM) {
194 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
195 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
196 		ptr = strstr(query_buffer, "SUBCHANNEL =");
197 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
198 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
199 		ptr = strstr(query_buffer, "CONMODE");
200 		/*
201 		 * Set the conmode to 3215 so that the device recognition
202 		 * will set the cu_type of the console to 3215. If the
203 		 * conmode is 3270 and we don't set it back then both
204 		 * 3215 and the 3270 driver will try to access the console
205 		 * device (3215 as console and 3270 as normal tty).
206 		 */
207 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
208 		if (ptr == NULL) {
209 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
210 			SET_CONSOLE_SCLP;
211 #endif
212 			return;
213 		}
214 		if (str_has_prefix(ptr + 8, "3270")) {
215 #if defined(CONFIG_TN3270_CONSOLE)
216 			SET_CONSOLE_3270;
217 #elif defined(CONFIG_TN3215_CONSOLE)
218 			SET_CONSOLE_3215;
219 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
220 			SET_CONSOLE_SCLP;
221 #endif
222 		} else if (str_has_prefix(ptr + 8, "3215")) {
223 #if defined(CONFIG_TN3215_CONSOLE)
224 			SET_CONSOLE_3215;
225 #elif defined(CONFIG_TN3270_CONSOLE)
226 			SET_CONSOLE_3270;
227 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
228 			SET_CONSOLE_SCLP;
229 #endif
230 		}
231 	} else if (MACHINE_IS_KVM) {
232 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
233 			SET_CONSOLE_VT220;
234 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
235 			SET_CONSOLE_SCLP;
236 		else
237 			SET_CONSOLE_HVC;
238 	} else {
239 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
240 		SET_CONSOLE_SCLP;
241 #endif
242 	}
243 }
244 
245 #ifdef CONFIG_CRASH_DUMP
246 static void __init setup_zfcpdump(void)
247 {
248 	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
249 		return;
250 	if (OLDMEM_BASE)
251 		return;
252 	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
253 	console_loglevel = 2;
254 }
255 #else
256 static inline void setup_zfcpdump(void) {}
257 #endif /* CONFIG_CRASH_DUMP */
258 
259  /*
260  * Reboot, halt and power_off stubs. They just call _machine_restart,
261  * _machine_halt or _machine_power_off.
262  */
263 
264 void machine_restart(char *command)
265 {
266 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
267 		/*
268 		 * Only unblank the console if we are called in enabled
269 		 * context or a bust_spinlocks cleared the way for us.
270 		 */
271 		console_unblank();
272 	_machine_restart(command);
273 }
274 
275 void machine_halt(void)
276 {
277 	if (!in_interrupt() || oops_in_progress)
278 		/*
279 		 * Only unblank the console if we are called in enabled
280 		 * context or a bust_spinlocks cleared the way for us.
281 		 */
282 		console_unblank();
283 	_machine_halt();
284 }
285 
286 void machine_power_off(void)
287 {
288 	if (!in_interrupt() || oops_in_progress)
289 		/*
290 		 * Only unblank the console if we are called in enabled
291 		 * context or a bust_spinlocks cleared the way for us.
292 		 */
293 		console_unblank();
294 	_machine_power_off();
295 }
296 
297 /*
298  * Dummy power off function.
299  */
300 void (*pm_power_off)(void) = machine_power_off;
301 EXPORT_SYMBOL_GPL(pm_power_off);
302 
303 void *restart_stack __section(.data);
304 
305 unsigned long stack_alloc(void)
306 {
307 #ifdef CONFIG_VMAP_STACK
308 	return (unsigned long)__vmalloc_node(THREAD_SIZE, THREAD_SIZE,
309 			THREADINFO_GFP, NUMA_NO_NODE,
310 			__builtin_return_address(0));
311 #else
312 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
313 #endif
314 }
315 
316 void stack_free(unsigned long stack)
317 {
318 #ifdef CONFIG_VMAP_STACK
319 	vfree((void *) stack);
320 #else
321 	free_pages(stack, THREAD_SIZE_ORDER);
322 #endif
323 }
324 
325 int __init arch_early_irq_init(void)
326 {
327 	unsigned long stack;
328 
329 	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
330 	if (!stack)
331 		panic("Couldn't allocate async stack");
332 	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
333 	return 0;
334 }
335 
336 static int __init async_stack_realloc(void)
337 {
338 	unsigned long old, new;
339 
340 	old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
341 	new = stack_alloc();
342 	if (!new)
343 		panic("Couldn't allocate async stack");
344 	S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
345 	free_pages(old, THREAD_SIZE_ORDER);
346 	return 0;
347 }
348 early_initcall(async_stack_realloc);
349 
350 void __init arch_call_rest_init(void)
351 {
352 	unsigned long stack;
353 
354 	stack = stack_alloc();
355 	if (!stack)
356 		panic("Couldn't allocate kernel stack");
357 	current->stack = (void *) stack;
358 #ifdef CONFIG_VMAP_STACK
359 	current->stack_vm_area = (void *) stack;
360 #endif
361 	set_task_stack_end_magic(current);
362 	stack += STACK_INIT_OFFSET;
363 	S390_lowcore.kernel_stack = stack;
364 	CALL_ON_STACK_NORETURN(rest_init, stack);
365 }
366 
367 static void __init setup_lowcore_dat_off(void)
368 {
369 	struct lowcore *lc;
370 
371 	/*
372 	 * Setup lowcore for boot cpu
373 	 */
374 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
375 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
376 	if (!lc)
377 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
378 		      __func__, sizeof(*lc), sizeof(*lc));
379 
380 	lc->restart_psw.mask = PSW_KERNEL_BITS;
381 	lc->restart_psw.addr = (unsigned long) restart_int_handler;
382 	lc->external_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
383 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
384 	lc->svc_new_psw.mask = PSW_KERNEL_BITS |
385 		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
386 	lc->svc_new_psw.addr = (unsigned long) system_call;
387 	lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
388 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
389 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
390 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
391 	lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
392 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
393 	lc->clock_comparator = clock_comparator_max;
394 	lc->nodat_stack = ((unsigned long) &init_thread_union)
395 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
396 	lc->current_task = (unsigned long)&init_task;
397 	lc->lpp = LPP_MAGIC;
398 	lc->machine_flags = S390_lowcore.machine_flags;
399 	lc->preempt_count = S390_lowcore.preempt_count;
400 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
401 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
402 	       sizeof(lc->stfle_fac_list));
403 	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
404 	       sizeof(lc->alt_stfle_fac_list));
405 	nmi_alloc_boot_cpu(lc);
406 	vdso_alloc_boot_cpu(lc);
407 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
408 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
409 	lc->exit_timer = S390_lowcore.exit_timer;
410 	lc->user_timer = S390_lowcore.user_timer;
411 	lc->system_timer = S390_lowcore.system_timer;
412 	lc->steal_timer = S390_lowcore.steal_timer;
413 	lc->last_update_timer = S390_lowcore.last_update_timer;
414 	lc->last_update_clock = S390_lowcore.last_update_clock;
415 
416 	/*
417 	 * Allocate the global restart stack which is the same for
418 	 * all CPUs in cast *one* of them does a PSW restart.
419 	 */
420 	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
421 	if (!restart_stack)
422 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
423 		      __func__, THREAD_SIZE, THREAD_SIZE);
424 	restart_stack += STACK_INIT_OFFSET;
425 
426 	/*
427 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
428 	 * restart data to the absolute zero lowcore. This is necessary if
429 	 * PSW restart is done on an offline CPU that has lowcore zero.
430 	 */
431 	lc->restart_stack = (unsigned long) restart_stack;
432 	lc->restart_fn = (unsigned long) do_restart;
433 	lc->restart_data = 0;
434 	lc->restart_source = -1UL;
435 
436 	/* Setup absolute zero lowcore */
437 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
438 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
439 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
440 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
441 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
442 
443 	lc->spinlock_lockval = arch_spin_lockval(0);
444 	lc->spinlock_index = 0;
445 	arch_spin_lock_setup(0);
446 	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
447 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
448 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
449 
450 	set_prefix((u32)(unsigned long) lc);
451 	lowcore_ptr[0] = lc;
452 }
453 
454 static void __init setup_lowcore_dat_on(void)
455 {
456 	__ctl_clear_bit(0, 28);
457 	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
458 	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
459 	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
460 	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
461 	__ctl_set_bit(0, 28);
462 }
463 
464 static struct resource code_resource = {
465 	.name  = "Kernel code",
466 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
467 };
468 
469 static struct resource data_resource = {
470 	.name = "Kernel data",
471 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
472 };
473 
474 static struct resource bss_resource = {
475 	.name = "Kernel bss",
476 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
477 };
478 
479 static struct resource __initdata *standard_resources[] = {
480 	&code_resource,
481 	&data_resource,
482 	&bss_resource,
483 };
484 
485 static void __init setup_resources(void)
486 {
487 	struct resource *res, *std_res, *sub_res;
488 	struct memblock_region *reg;
489 	int j;
490 
491 	code_resource.start = (unsigned long) _text;
492 	code_resource.end = (unsigned long) _etext - 1;
493 	data_resource.start = (unsigned long) _etext;
494 	data_resource.end = (unsigned long) _edata - 1;
495 	bss_resource.start = (unsigned long) __bss_start;
496 	bss_resource.end = (unsigned long) __bss_stop - 1;
497 
498 	for_each_memblock(memory, reg) {
499 		res = memblock_alloc(sizeof(*res), 8);
500 		if (!res)
501 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
502 			      __func__, sizeof(*res), 8);
503 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
504 
505 		res->name = "System RAM";
506 		res->start = reg->base;
507 		res->end = reg->base + reg->size - 1;
508 		request_resource(&iomem_resource, res);
509 
510 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
511 			std_res = standard_resources[j];
512 			if (std_res->start < res->start ||
513 			    std_res->start > res->end)
514 				continue;
515 			if (std_res->end > res->end) {
516 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
517 				if (!sub_res)
518 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
519 					      __func__, sizeof(*sub_res), 8);
520 				*sub_res = *std_res;
521 				sub_res->end = res->end;
522 				std_res->start = res->end + 1;
523 				request_resource(res, sub_res);
524 			} else {
525 				request_resource(res, std_res);
526 			}
527 		}
528 	}
529 #ifdef CONFIG_CRASH_DUMP
530 	/*
531 	 * Re-add removed crash kernel memory as reserved memory. This makes
532 	 * sure it will be mapped with the identity mapping and struct pages
533 	 * will be created, so it can be resized later on.
534 	 * However add it later since the crash kernel resource should not be
535 	 * part of the System RAM resource.
536 	 */
537 	if (crashk_res.end) {
538 		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
539 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
540 		insert_resource(&iomem_resource, &crashk_res);
541 	}
542 #endif
543 }
544 
545 static void __init setup_memory_end(void)
546 {
547 	unsigned long vmax, tmp;
548 
549 	/* Choose kernel address space layout: 3 or 4 levels. */
550 	if (IS_ENABLED(CONFIG_KASAN)) {
551 		vmax = IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)
552 			   ? _REGION1_SIZE
553 			   : _REGION2_SIZE;
554 	} else {
555 		tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
556 		tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
557 		if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
558 			vmax = _REGION2_SIZE; /* 3-level kernel page table */
559 		else
560 			vmax = _REGION1_SIZE; /* 4-level kernel page table */
561 	}
562 
563 	if (is_prot_virt_host())
564 		adjust_to_uv_max(&vmax);
565 
566 	/* module area is at the end of the kernel address space. */
567 	MODULES_END = vmax;
568 	MODULES_VADDR = MODULES_END - MODULES_LEN;
569 	VMALLOC_END = MODULES_VADDR;
570 	VMALLOC_START = VMALLOC_END - vmalloc_size;
571 
572 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
573 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
574 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
575 	tmp = SECTION_ALIGN_UP(tmp);
576 	tmp = VMALLOC_START - tmp * sizeof(struct page);
577 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
578 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
579 	vmemmap = (struct page *) tmp;
580 
581 	/* Take care that memory_end is set and <= vmemmap */
582 	memory_end = min(memory_end ?: max_physmem_end, (unsigned long)vmemmap);
583 #ifdef CONFIG_KASAN
584 	/* fit in kasan shadow memory region between 1:1 and vmemmap */
585 	memory_end = min(memory_end, KASAN_SHADOW_START);
586 	vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
587 #endif
588 	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
589 	memblock_remove(memory_end, ULONG_MAX);
590 
591 	pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
592 }
593 
594 #ifdef CONFIG_CRASH_DUMP
595 
596 /*
597  * When kdump is enabled, we have to ensure that no memory from
598  * the area [0 - crashkernel memory size] and
599  * [crashk_res.start - crashk_res.end] is set offline.
600  */
601 static int kdump_mem_notifier(struct notifier_block *nb,
602 			      unsigned long action, void *data)
603 {
604 	struct memory_notify *arg = data;
605 
606 	if (action != MEM_GOING_OFFLINE)
607 		return NOTIFY_OK;
608 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
609 		return NOTIFY_BAD;
610 	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
611 		return NOTIFY_OK;
612 	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
613 		return NOTIFY_OK;
614 	return NOTIFY_BAD;
615 }
616 
617 static struct notifier_block kdump_mem_nb = {
618 	.notifier_call = kdump_mem_notifier,
619 };
620 
621 #endif
622 
623 /*
624  * Make sure that the area behind memory_end is protected
625  */
626 static void reserve_memory_end(void)
627 {
628 	if (memory_end_set)
629 		memblock_reserve(memory_end, ULONG_MAX);
630 }
631 
632 /*
633  * Make sure that oldmem, where the dump is stored, is protected
634  */
635 static void reserve_oldmem(void)
636 {
637 #ifdef CONFIG_CRASH_DUMP
638 	if (OLDMEM_BASE)
639 		/* Forget all memory above the running kdump system */
640 		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
641 #endif
642 }
643 
644 /*
645  * Make sure that oldmem, where the dump is stored, is protected
646  */
647 static void remove_oldmem(void)
648 {
649 #ifdef CONFIG_CRASH_DUMP
650 	if (OLDMEM_BASE)
651 		/* Forget all memory above the running kdump system */
652 		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
653 #endif
654 }
655 
656 /*
657  * Reserve memory for kdump kernel to be loaded with kexec
658  */
659 static void __init reserve_crashkernel(void)
660 {
661 #ifdef CONFIG_CRASH_DUMP
662 	unsigned long long crash_base, crash_size;
663 	phys_addr_t low, high;
664 	int rc;
665 
666 	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
667 			       &crash_base);
668 
669 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
670 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
671 	if (rc || crash_size == 0)
672 		return;
673 
674 	if (memblock.memory.regions[0].size < crash_size) {
675 		pr_info("crashkernel reservation failed: %s\n",
676 			"first memory chunk must be at least crashkernel size");
677 		return;
678 	}
679 
680 	low = crash_base ?: OLDMEM_BASE;
681 	high = low + crash_size;
682 	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
683 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
684 		crash_base = low;
685 	} else {
686 		/* Find suitable area in free memory */
687 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
688 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
689 
690 		if (crash_base && crash_base < low) {
691 			pr_info("crashkernel reservation failed: %s\n",
692 				"crash_base too low");
693 			return;
694 		}
695 		low = crash_base ?: low;
696 		crash_base = memblock_find_in_range(low, high, crash_size,
697 						    KEXEC_CRASH_MEM_ALIGN);
698 	}
699 
700 	if (!crash_base) {
701 		pr_info("crashkernel reservation failed: %s\n",
702 			"no suitable area found");
703 		return;
704 	}
705 
706 	if (register_memory_notifier(&kdump_mem_nb))
707 		return;
708 
709 	if (!OLDMEM_BASE && MACHINE_IS_VM)
710 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
711 	crashk_res.start = crash_base;
712 	crashk_res.end = crash_base + crash_size - 1;
713 	memblock_remove(crash_base, crash_size);
714 	pr_info("Reserving %lluMB of memory at %lluMB "
715 		"for crashkernel (System RAM: %luMB)\n",
716 		crash_size >> 20, crash_base >> 20,
717 		(unsigned long)memblock.memory.total_size >> 20);
718 	os_info_crashkernel_add(crash_base, crash_size);
719 #endif
720 }
721 
722 /*
723  * Reserve the initrd from being used by memblock
724  */
725 static void __init reserve_initrd(void)
726 {
727 #ifdef CONFIG_BLK_DEV_INITRD
728 	if (!INITRD_START || !INITRD_SIZE)
729 		return;
730 	initrd_start = INITRD_START;
731 	initrd_end = initrd_start + INITRD_SIZE;
732 	memblock_reserve(INITRD_START, INITRD_SIZE);
733 #endif
734 }
735 
736 /*
737  * Reserve the memory area used to pass the certificate lists
738  */
739 static void __init reserve_certificate_list(void)
740 {
741 	if (ipl_cert_list_addr)
742 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
743 }
744 
745 static void __init reserve_mem_detect_info(void)
746 {
747 	unsigned long start, size;
748 
749 	get_mem_detect_reserved(&start, &size);
750 	if (size)
751 		memblock_reserve(start, size);
752 }
753 
754 static void __init free_mem_detect_info(void)
755 {
756 	unsigned long start, size;
757 
758 	get_mem_detect_reserved(&start, &size);
759 	if (size)
760 		memblock_free(start, size);
761 }
762 
763 static const char * __init get_mem_info_source(void)
764 {
765 	switch (mem_detect.info_source) {
766 	case MEM_DETECT_SCLP_STOR_INFO:
767 		return "sclp storage info";
768 	case MEM_DETECT_DIAG260:
769 		return "diag260";
770 	case MEM_DETECT_SCLP_READ_INFO:
771 		return "sclp read info";
772 	case MEM_DETECT_BIN_SEARCH:
773 		return "binary search";
774 	}
775 	return "none";
776 }
777 
778 static void __init memblock_add_mem_detect_info(void)
779 {
780 	unsigned long start, end;
781 	int i;
782 
783 	memblock_dbg("physmem info source: %s (%hhd)\n",
784 		     get_mem_info_source(), mem_detect.info_source);
785 	/* keep memblock lists close to the kernel */
786 	memblock_set_bottom_up(true);
787 	for_each_mem_detect_block(i, &start, &end) {
788 		memblock_add(start, end - start);
789 		memblock_physmem_add(start, end - start);
790 	}
791 	memblock_set_bottom_up(false);
792 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
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 	if (is_prot_virt_host())
1142 		setup_uv();
1143 	setup_memory_end();
1144 	setup_memory();
1145 	dma_contiguous_reserve(memory_end);
1146 	vmcp_cma_reserve();
1147 
1148 	check_initrd();
1149 	reserve_crashkernel();
1150 #ifdef CONFIG_CRASH_DUMP
1151 	/*
1152 	 * Be aware that smp_save_dump_cpus() triggers a system reset.
1153 	 * Therefore CPU and device initialization should be done afterwards.
1154 	 */
1155 	smp_save_dump_cpus();
1156 #endif
1157 
1158 	setup_resources();
1159 	setup_lowcore_dat_off();
1160 	smp_fill_possible_mask();
1161 	cpu_detect_mhz_feature();
1162         cpu_init();
1163 	numa_setup();
1164 	smp_detect_cpus();
1165 	topology_init_early();
1166 
1167 	/*
1168 	 * Create kernel page tables and switch to virtual addressing.
1169 	 */
1170         paging_init();
1171 
1172 	/*
1173 	 * After paging_init created the kernel page table, the new PSWs
1174 	 * in lowcore can now run with DAT enabled.
1175 	 */
1176 	setup_lowcore_dat_on();
1177 
1178         /* Setup default console */
1179 	conmode_default();
1180 	set_preferred_console();
1181 
1182 	apply_alternative_instructions();
1183 	if (IS_ENABLED(CONFIG_EXPOLINE))
1184 		nospec_init_branches();
1185 
1186 	/* Setup zfcpdump support */
1187 	setup_zfcpdump();
1188 
1189 	/* Add system specific data to the random pool */
1190 	setup_randomness();
1191 }
1192