xref: /openbmc/linux/arch/s390/kernel/setup.c (revision 7e60e389)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999, 2012
5  *    Author(s): Hartmut Penner (hp@de.ibm.com),
6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *
8  *  Derived from "arch/i386/kernel/setup.c"
9  *    Copyright (C) 1995, Linus Torvalds
10  */
11 
12 /*
13  * This file handles the architecture-dependent parts of initialization
14  */
15 
16 #define KMSG_COMPONENT "setup"
17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
18 
19 #include <linux/errno.h>
20 #include <linux/export.h>
21 #include <linux/sched.h>
22 #include <linux/sched/task.h>
23 #include <linux/cpu.h>
24 #include <linux/kernel.h>
25 #include <linux/memblock.h>
26 #include <linux/mm.h>
27 #include <linux/stddef.h>
28 #include <linux/unistd.h>
29 #include <linux/ptrace.h>
30 #include <linux/random.h>
31 #include <linux/user.h>
32 #include <linux/tty.h>
33 #include <linux/ioport.h>
34 #include <linux/delay.h>
35 #include <linux/init.h>
36 #include <linux/initrd.h>
37 #include <linux/root_dev.h>
38 #include <linux/console.h>
39 #include <linux/kernel_stat.h>
40 #include <linux/dma-map-ops.h>
41 #include <linux/device.h>
42 #include <linux/notifier.h>
43 #include <linux/pfn.h>
44 #include <linux/ctype.h>
45 #include <linux/reboot.h>
46 #include <linux/topology.h>
47 #include <linux/kexec.h>
48 #include <linux/crash_dump.h>
49 #include <linux/memory.h>
50 #include <linux/compat.h>
51 #include <linux/start_kernel.h>
52 #include <linux/hugetlb.h>
53 
54 #include <asm/boot_data.h>
55 #include <asm/ipl.h>
56 #include <asm/facility.h>
57 #include <asm/smp.h>
58 #include <asm/mmu_context.h>
59 #include <asm/cpcmd.h>
60 #include <asm/lowcore.h>
61 #include <asm/nmi.h>
62 #include <asm/irq.h>
63 #include <asm/page.h>
64 #include <asm/ptrace.h>
65 #include <asm/sections.h>
66 #include <asm/ebcdic.h>
67 #include <asm/diag.h>
68 #include <asm/os_info.h>
69 #include <asm/sclp.h>
70 #include <asm/stacktrace.h>
71 #include <asm/sysinfo.h>
72 #include <asm/numa.h>
73 #include <asm/alternative.h>
74 #include <asm/nospec-branch.h>
75 #include <asm/mem_detect.h>
76 #include <asm/uv.h>
77 #include <asm/asm-offsets.h>
78 #include "entry.h"
79 
80 /*
81  * Machine setup..
82  */
83 unsigned int console_mode = 0;
84 EXPORT_SYMBOL(console_mode);
85 
86 unsigned int console_devno = -1;
87 EXPORT_SYMBOL(console_devno);
88 
89 unsigned int console_irq = -1;
90 EXPORT_SYMBOL(console_irq);
91 
92 unsigned long elf_hwcap __read_mostly = 0;
93 char elf_platform[ELF_PLATFORM_SIZE];
94 
95 unsigned long int_hwcap = 0;
96 
97 int __bootdata(noexec_disabled);
98 unsigned long __bootdata(ident_map_size);
99 unsigned long __bootdata(vmalloc_size);
100 struct mem_detect_info __bootdata(mem_detect);
101 
102 struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
103 struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
104 unsigned long __bootdata_preserved(__stext_dma);
105 unsigned long __bootdata_preserved(__etext_dma);
106 unsigned long __bootdata_preserved(__sdma);
107 unsigned long __bootdata_preserved(__edma);
108 unsigned long __bootdata_preserved(__kaslr_offset);
109 unsigned int __bootdata_preserved(zlib_dfltcc_support);
110 EXPORT_SYMBOL(zlib_dfltcc_support);
111 
112 unsigned long VMALLOC_START;
113 EXPORT_SYMBOL(VMALLOC_START);
114 
115 unsigned long VMALLOC_END;
116 EXPORT_SYMBOL(VMALLOC_END);
117 
118 struct page *vmemmap;
119 EXPORT_SYMBOL(vmemmap);
120 unsigned long vmemmap_size;
121 
122 unsigned long MODULES_VADDR;
123 unsigned long MODULES_END;
124 
125 /* An array with a pointer to the lowcore of every CPU. */
126 struct lowcore *lowcore_ptr[NR_CPUS];
127 EXPORT_SYMBOL(lowcore_ptr);
128 
129 /*
130  * The Write Back bit position in the physaddr is given by the SLPC PCI.
131  * Leaving the mask zero always uses write through which is safe
132  */
133 unsigned long mio_wb_bit_mask __ro_after_init;
134 
135 /*
136  * This is set up by the setup-routine at boot-time
137  * for S390 need to find out, what we have to setup
138  * using address 0x10400 ...
139  */
140 
141 #include <asm/setup.h>
142 
143 /*
144  * condev= and conmode= setup parameter.
145  */
146 
147 static int __init condev_setup(char *str)
148 {
149 	int vdev;
150 
151 	vdev = simple_strtoul(str, &str, 0);
152 	if (vdev >= 0 && vdev < 65536) {
153 		console_devno = vdev;
154 		console_irq = -1;
155 	}
156 	return 1;
157 }
158 
159 __setup("condev=", condev_setup);
160 
161 static void __init set_preferred_console(void)
162 {
163 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
164 		add_preferred_console("ttyS", 0, NULL);
165 	else if (CONSOLE_IS_3270)
166 		add_preferred_console("tty3270", 0, NULL);
167 	else if (CONSOLE_IS_VT220)
168 		add_preferred_console("ttyS", 1, NULL);
169 	else if (CONSOLE_IS_HVC)
170 		add_preferred_console("hvc", 0, NULL);
171 }
172 
173 static int __init conmode_setup(char *str)
174 {
175 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
176 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
177                 SET_CONSOLE_SCLP;
178 #endif
179 #if defined(CONFIG_TN3215_CONSOLE)
180 	if (!strcmp(str, "3215"))
181 		SET_CONSOLE_3215;
182 #endif
183 #if defined(CONFIG_TN3270_CONSOLE)
184 	if (!strcmp(str, "3270"))
185 		SET_CONSOLE_3270;
186 #endif
187 	set_preferred_console();
188         return 1;
189 }
190 
191 __setup("conmode=", conmode_setup);
192 
193 static void __init conmode_default(void)
194 {
195 	char query_buffer[1024];
196 	char *ptr;
197 
198         if (MACHINE_IS_VM) {
199 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
200 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
201 		ptr = strstr(query_buffer, "SUBCHANNEL =");
202 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
203 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
204 		ptr = strstr(query_buffer, "CONMODE");
205 		/*
206 		 * Set the conmode to 3215 so that the device recognition
207 		 * will set the cu_type of the console to 3215. If the
208 		 * conmode is 3270 and we don't set it back then both
209 		 * 3215 and the 3270 driver will try to access the console
210 		 * device (3215 as console and 3270 as normal tty).
211 		 */
212 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
213 		if (ptr == NULL) {
214 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
215 			SET_CONSOLE_SCLP;
216 #endif
217 			return;
218 		}
219 		if (str_has_prefix(ptr + 8, "3270")) {
220 #if defined(CONFIG_TN3270_CONSOLE)
221 			SET_CONSOLE_3270;
222 #elif defined(CONFIG_TN3215_CONSOLE)
223 			SET_CONSOLE_3215;
224 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
225 			SET_CONSOLE_SCLP;
226 #endif
227 		} else if (str_has_prefix(ptr + 8, "3215")) {
228 #if defined(CONFIG_TN3215_CONSOLE)
229 			SET_CONSOLE_3215;
230 #elif defined(CONFIG_TN3270_CONSOLE)
231 			SET_CONSOLE_3270;
232 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
233 			SET_CONSOLE_SCLP;
234 #endif
235 		}
236 	} else if (MACHINE_IS_KVM) {
237 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
238 			SET_CONSOLE_VT220;
239 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
240 			SET_CONSOLE_SCLP;
241 		else
242 			SET_CONSOLE_HVC;
243 	} else {
244 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
245 		SET_CONSOLE_SCLP;
246 #endif
247 	}
248 }
249 
250 #ifdef CONFIG_CRASH_DUMP
251 static void __init setup_zfcpdump(void)
252 {
253 	if (!is_ipl_type_dump())
254 		return;
255 	if (OLDMEM_BASE)
256 		return;
257 	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
258 	console_loglevel = 2;
259 }
260 #else
261 static inline void setup_zfcpdump(void) {}
262 #endif /* CONFIG_CRASH_DUMP */
263 
264  /*
265  * Reboot, halt and power_off stubs. They just call _machine_restart,
266  * _machine_halt or _machine_power_off.
267  */
268 
269 void machine_restart(char *command)
270 {
271 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
272 		/*
273 		 * Only unblank the console if we are called in enabled
274 		 * context or a bust_spinlocks cleared the way for us.
275 		 */
276 		console_unblank();
277 	_machine_restart(command);
278 }
279 
280 void machine_halt(void)
281 {
282 	if (!in_interrupt() || oops_in_progress)
283 		/*
284 		 * Only unblank the console if we are called in enabled
285 		 * context or a bust_spinlocks cleared the way for us.
286 		 */
287 		console_unblank();
288 	_machine_halt();
289 }
290 
291 void machine_power_off(void)
292 {
293 	if (!in_interrupt() || oops_in_progress)
294 		/*
295 		 * Only unblank the console if we are called in enabled
296 		 * context or a bust_spinlocks cleared the way for us.
297 		 */
298 		console_unblank();
299 	_machine_power_off();
300 }
301 
302 /*
303  * Dummy power off function.
304  */
305 void (*pm_power_off)(void) = machine_power_off;
306 EXPORT_SYMBOL_GPL(pm_power_off);
307 
308 void *restart_stack;
309 
310 unsigned long stack_alloc(void)
311 {
312 #ifdef CONFIG_VMAP_STACK
313 	return (unsigned long)__vmalloc_node(THREAD_SIZE, THREAD_SIZE,
314 			THREADINFO_GFP, NUMA_NO_NODE,
315 			__builtin_return_address(0));
316 #else
317 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
318 #endif
319 }
320 
321 void stack_free(unsigned long stack)
322 {
323 #ifdef CONFIG_VMAP_STACK
324 	vfree((void *) stack);
325 #else
326 	free_pages(stack, THREAD_SIZE_ORDER);
327 #endif
328 }
329 
330 int __init arch_early_irq_init(void)
331 {
332 	unsigned long stack;
333 
334 	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
335 	if (!stack)
336 		panic("Couldn't allocate async stack");
337 	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
338 	return 0;
339 }
340 
341 static int __init async_stack_realloc(void)
342 {
343 	unsigned long old, new;
344 
345 	old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
346 	new = stack_alloc();
347 	if (!new)
348 		panic("Couldn't allocate async stack");
349 	S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
350 	free_pages(old, THREAD_SIZE_ORDER);
351 	return 0;
352 }
353 early_initcall(async_stack_realloc);
354 
355 void __init arch_call_rest_init(void)
356 {
357 	unsigned long stack;
358 
359 	stack = stack_alloc();
360 	if (!stack)
361 		panic("Couldn't allocate kernel stack");
362 	current->stack = (void *) stack;
363 #ifdef CONFIG_VMAP_STACK
364 	current->stack_vm_area = (void *) stack;
365 #endif
366 	set_task_stack_end_magic(current);
367 	stack += STACK_INIT_OFFSET;
368 	S390_lowcore.kernel_stack = stack;
369 	CALL_ON_STACK_NORETURN(rest_init, stack);
370 }
371 
372 static void __init setup_lowcore_dat_off(void)
373 {
374 	unsigned long int_psw_mask = PSW_KERNEL_BITS;
375 	struct lowcore *lc;
376 
377 	if (IS_ENABLED(CONFIG_KASAN))
378 		int_psw_mask |= PSW_MASK_DAT;
379 
380 	/*
381 	 * Setup lowcore for boot cpu
382 	 */
383 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
384 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
385 	if (!lc)
386 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
387 		      __func__, sizeof(*lc), sizeof(*lc));
388 
389 	lc->restart_psw.mask = PSW_KERNEL_BITS;
390 	lc->restart_psw.addr = (unsigned long) restart_int_handler;
391 	lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
392 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
393 	lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
394 	lc->svc_new_psw.addr = (unsigned long) system_call;
395 	lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
396 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
397 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
398 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
399 	lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
400 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
401 	lc->clock_comparator = clock_comparator_max;
402 	lc->nodat_stack = ((unsigned long) &init_thread_union)
403 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
404 	lc->current_task = (unsigned long)&init_task;
405 	lc->lpp = LPP_MAGIC;
406 	lc->machine_flags = S390_lowcore.machine_flags;
407 	lc->preempt_count = S390_lowcore.preempt_count;
408 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
409 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
410 	       sizeof(lc->stfle_fac_list));
411 	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
412 	       sizeof(lc->alt_stfle_fac_list));
413 	nmi_alloc_boot_cpu(lc);
414 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
415 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
416 	lc->exit_timer = S390_lowcore.exit_timer;
417 	lc->user_timer = S390_lowcore.user_timer;
418 	lc->system_timer = S390_lowcore.system_timer;
419 	lc->steal_timer = S390_lowcore.steal_timer;
420 	lc->last_update_timer = S390_lowcore.last_update_timer;
421 	lc->last_update_clock = S390_lowcore.last_update_clock;
422 
423 	/*
424 	 * Allocate the global restart stack which is the same for
425 	 * all CPUs in cast *one* of them does a PSW restart.
426 	 */
427 	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
428 	if (!restart_stack)
429 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
430 		      __func__, THREAD_SIZE, THREAD_SIZE);
431 	restart_stack += STACK_INIT_OFFSET;
432 
433 	/*
434 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
435 	 * restart data to the absolute zero lowcore. This is necessary if
436 	 * PSW restart is done on an offline CPU that has lowcore zero.
437 	 */
438 	lc->restart_stack = (unsigned long) restart_stack;
439 	lc->restart_fn = (unsigned long) do_restart;
440 	lc->restart_data = 0;
441 	lc->restart_source = -1UL;
442 
443 	/* Setup absolute zero lowcore */
444 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
445 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
446 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
447 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
448 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
449 
450 	lc->spinlock_lockval = arch_spin_lockval(0);
451 	lc->spinlock_index = 0;
452 	arch_spin_lock_setup(0);
453 	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
454 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
455 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
456 
457 	set_prefix((u32)(unsigned long) lc);
458 	lowcore_ptr[0] = lc;
459 }
460 
461 static void __init setup_lowcore_dat_on(void)
462 {
463 	__ctl_clear_bit(0, 28);
464 	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
465 	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
466 	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
467 	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
468 	__ctl_set_bit(0, 28);
469 }
470 
471 static struct resource code_resource = {
472 	.name  = "Kernel code",
473 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
474 };
475 
476 static struct resource data_resource = {
477 	.name = "Kernel data",
478 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
479 };
480 
481 static struct resource bss_resource = {
482 	.name = "Kernel bss",
483 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
484 };
485 
486 static struct resource __initdata *standard_resources[] = {
487 	&code_resource,
488 	&data_resource,
489 	&bss_resource,
490 };
491 
492 static void __init setup_resources(void)
493 {
494 	struct resource *res, *std_res, *sub_res;
495 	phys_addr_t start, end;
496 	int j;
497 	u64 i;
498 
499 	code_resource.start = (unsigned long) _text;
500 	code_resource.end = (unsigned long) _etext - 1;
501 	data_resource.start = (unsigned long) _etext;
502 	data_resource.end = (unsigned long) _edata - 1;
503 	bss_resource.start = (unsigned long) __bss_start;
504 	bss_resource.end = (unsigned long) __bss_stop - 1;
505 
506 	for_each_mem_range(i, &start, &end) {
507 		res = memblock_alloc(sizeof(*res), 8);
508 		if (!res)
509 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
510 			      __func__, sizeof(*res), 8);
511 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
512 
513 		res->name = "System RAM";
514 		res->start = start;
515 		/*
516 		 * In memblock, end points to the first byte after the
517 		 * range while in resourses, end points to the last byte in
518 		 * the range.
519 		 */
520 		res->end = end - 1;
521 		request_resource(&iomem_resource, res);
522 
523 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
524 			std_res = standard_resources[j];
525 			if (std_res->start < res->start ||
526 			    std_res->start > res->end)
527 				continue;
528 			if (std_res->end > res->end) {
529 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
530 				if (!sub_res)
531 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
532 					      __func__, sizeof(*sub_res), 8);
533 				*sub_res = *std_res;
534 				sub_res->end = res->end;
535 				std_res->start = res->end + 1;
536 				request_resource(res, sub_res);
537 			} else {
538 				request_resource(res, std_res);
539 			}
540 		}
541 	}
542 #ifdef CONFIG_CRASH_DUMP
543 	/*
544 	 * Re-add removed crash kernel memory as reserved memory. This makes
545 	 * sure it will be mapped with the identity mapping and struct pages
546 	 * will be created, so it can be resized later on.
547 	 * However add it later since the crash kernel resource should not be
548 	 * part of the System RAM resource.
549 	 */
550 	if (crashk_res.end) {
551 		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
552 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
553 		insert_resource(&iomem_resource, &crashk_res);
554 	}
555 #endif
556 }
557 
558 static void __init setup_ident_map_size(void)
559 {
560 	unsigned long vmax, tmp;
561 
562 	/* Choose kernel address space layout: 3 or 4 levels. */
563 	tmp = ident_map_size / PAGE_SIZE;
564 	tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
565 	if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
566 		vmax = _REGION2_SIZE; /* 3-level kernel page table */
567 	else
568 		vmax = _REGION1_SIZE; /* 4-level kernel page table */
569 	/* module area is at the end of the kernel address space. */
570 	MODULES_END = vmax;
571 	if (is_prot_virt_host())
572 		adjust_to_uv_max(&MODULES_END);
573 #ifdef CONFIG_KASAN
574 	vmax = _REGION1_SIZE;
575 	MODULES_END = kasan_vmax;
576 #endif
577 	MODULES_VADDR = MODULES_END - MODULES_LEN;
578 	VMALLOC_END = MODULES_VADDR;
579 	VMALLOC_START = VMALLOC_END - vmalloc_size;
580 
581 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
582 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
583 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
584 	tmp = SECTION_ALIGN_UP(tmp);
585 	tmp = VMALLOC_START - tmp * sizeof(struct page);
586 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
587 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
588 	vmemmap = (struct page *) tmp;
589 
590 	/* Take care that ident_map_size <= vmemmap */
591 	ident_map_size = min(ident_map_size, (unsigned long)vmemmap);
592 #ifdef CONFIG_KASAN
593 	ident_map_size = min(ident_map_size, KASAN_SHADOW_START);
594 #endif
595 	vmemmap_size = SECTION_ALIGN_UP(ident_map_size / PAGE_SIZE) * sizeof(struct page);
596 #ifdef CONFIG_KASAN
597 	/* move vmemmap above kasan shadow only if stands in a way */
598 	if (KASAN_SHADOW_END > (unsigned long)vmemmap &&
599 	    (unsigned long)vmemmap + vmemmap_size > KASAN_SHADOW_START)
600 		vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
601 #endif
602 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
603 	memblock_remove(ident_map_size, ULONG_MAX);
604 
605 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
606 }
607 
608 #ifdef CONFIG_CRASH_DUMP
609 
610 /*
611  * When kdump is enabled, we have to ensure that no memory from the area
612  * [0 - crashkernel memory size] is set offline - it will be exchanged with
613  * the crashkernel memory region when kdump is triggered. The crashkernel
614  * memory region can never get offlined (pages are unmovable).
615  */
616 static int kdump_mem_notifier(struct notifier_block *nb,
617 			      unsigned long action, void *data)
618 {
619 	struct memory_notify *arg = data;
620 
621 	if (action != MEM_GOING_OFFLINE)
622 		return NOTIFY_OK;
623 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
624 		return NOTIFY_BAD;
625 	return NOTIFY_OK;
626 }
627 
628 static struct notifier_block kdump_mem_nb = {
629 	.notifier_call = kdump_mem_notifier,
630 };
631 
632 #endif
633 
634 /*
635  * Make sure that the area above identity mapping is protected
636  */
637 static void __init reserve_above_ident_map(void)
638 {
639 	memblock_reserve(ident_map_size, ULONG_MAX);
640 }
641 
642 /*
643  * Make sure that oldmem, where the dump is stored, is protected
644  */
645 static void __init reserve_oldmem(void)
646 {
647 #ifdef CONFIG_CRASH_DUMP
648 	if (OLDMEM_BASE)
649 		/* Forget all memory above the running kdump system */
650 		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
651 #endif
652 }
653 
654 /*
655  * Make sure that oldmem, where the dump is stored, is protected
656  */
657 static void __init remove_oldmem(void)
658 {
659 #ifdef CONFIG_CRASH_DUMP
660 	if (OLDMEM_BASE)
661 		/* Forget all memory above the running kdump system */
662 		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
663 #endif
664 }
665 
666 /*
667  * Reserve memory for kdump kernel to be loaded with kexec
668  */
669 static void __init reserve_crashkernel(void)
670 {
671 #ifdef CONFIG_CRASH_DUMP
672 	unsigned long long crash_base, crash_size;
673 	phys_addr_t low, high;
674 	int rc;
675 
676 	rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
677 			       &crash_base);
678 
679 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
680 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
681 	if (rc || crash_size == 0)
682 		return;
683 
684 	if (memblock.memory.regions[0].size < crash_size) {
685 		pr_info("crashkernel reservation failed: %s\n",
686 			"first memory chunk must be at least crashkernel size");
687 		return;
688 	}
689 
690 	low = crash_base ?: OLDMEM_BASE;
691 	high = low + crash_size;
692 	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
693 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
694 		crash_base = low;
695 	} else {
696 		/* Find suitable area in free memory */
697 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
698 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
699 
700 		if (crash_base && crash_base < low) {
701 			pr_info("crashkernel reservation failed: %s\n",
702 				"crash_base too low");
703 			return;
704 		}
705 		low = crash_base ?: low;
706 		crash_base = memblock_find_in_range(low, high, crash_size,
707 						    KEXEC_CRASH_MEM_ALIGN);
708 	}
709 
710 	if (!crash_base) {
711 		pr_info("crashkernel reservation failed: %s\n",
712 			"no suitable area found");
713 		return;
714 	}
715 
716 	if (register_memory_notifier(&kdump_mem_nb))
717 		return;
718 
719 	if (!OLDMEM_BASE && MACHINE_IS_VM)
720 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
721 	crashk_res.start = crash_base;
722 	crashk_res.end = crash_base + crash_size - 1;
723 	memblock_remove(crash_base, crash_size);
724 	pr_info("Reserving %lluMB of memory at %lluMB "
725 		"for crashkernel (System RAM: %luMB)\n",
726 		crash_size >> 20, crash_base >> 20,
727 		(unsigned long)memblock.memory.total_size >> 20);
728 	os_info_crashkernel_add(crash_base, crash_size);
729 #endif
730 }
731 
732 /*
733  * Reserve the initrd from being used by memblock
734  */
735 static void __init reserve_initrd(void)
736 {
737 #ifdef CONFIG_BLK_DEV_INITRD
738 	if (!INITRD_START || !INITRD_SIZE)
739 		return;
740 	initrd_start = INITRD_START;
741 	initrd_end = initrd_start + INITRD_SIZE;
742 	memblock_reserve(INITRD_START, INITRD_SIZE);
743 #endif
744 }
745 
746 /*
747  * Reserve the memory area used to pass the certificate lists
748  */
749 static void __init reserve_certificate_list(void)
750 {
751 	if (ipl_cert_list_addr)
752 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
753 }
754 
755 static void __init reserve_mem_detect_info(void)
756 {
757 	unsigned long start, size;
758 
759 	get_mem_detect_reserved(&start, &size);
760 	if (size)
761 		memblock_reserve(start, size);
762 }
763 
764 static void __init free_mem_detect_info(void)
765 {
766 	unsigned long start, size;
767 
768 	get_mem_detect_reserved(&start, &size);
769 	if (size)
770 		memblock_free(start, size);
771 }
772 
773 static const char * __init get_mem_info_source(void)
774 {
775 	switch (mem_detect.info_source) {
776 	case MEM_DETECT_SCLP_STOR_INFO:
777 		return "sclp storage info";
778 	case MEM_DETECT_DIAG260:
779 		return "diag260";
780 	case MEM_DETECT_SCLP_READ_INFO:
781 		return "sclp read info";
782 	case MEM_DETECT_BIN_SEARCH:
783 		return "binary search";
784 	}
785 	return "none";
786 }
787 
788 static void __init memblock_add_mem_detect_info(void)
789 {
790 	unsigned long start, end;
791 	int i;
792 
793 	pr_debug("physmem info source: %s (%hhd)\n",
794 		 get_mem_info_source(), mem_detect.info_source);
795 	/* keep memblock lists close to the kernel */
796 	memblock_set_bottom_up(true);
797 	for_each_mem_detect_block(i, &start, &end) {
798 		memblock_add(start, end - start);
799 		memblock_physmem_add(start, end - start);
800 	}
801 	memblock_set_bottom_up(false);
802 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
803 	memblock_dump_all();
804 }
805 
806 /*
807  * Check for initrd being in usable memory
808  */
809 static void __init check_initrd(void)
810 {
811 #ifdef CONFIG_BLK_DEV_INITRD
812 	if (INITRD_START && INITRD_SIZE &&
813 	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
814 		pr_err("The initial RAM disk does not fit into the memory\n");
815 		memblock_free(INITRD_START, INITRD_SIZE);
816 		initrd_start = initrd_end = 0;
817 	}
818 #endif
819 }
820 
821 /*
822  * Reserve memory used for lowcore/command line/kernel image.
823  */
824 static void __init reserve_kernel(void)
825 {
826 	unsigned long start_pfn = PFN_UP(__pa(_end));
827 
828 	memblock_reserve(0, HEAD_END);
829 	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
830 			 - (unsigned long)_stext);
831 	memblock_reserve(__sdma, __edma - __sdma);
832 }
833 
834 static void __init setup_memory(void)
835 {
836 	phys_addr_t start, end;
837 	u64 i;
838 
839 	/*
840 	 * Init storage key for present memory
841 	 */
842 	for_each_mem_range(i, &start, &end)
843 		storage_key_init_range(start, end);
844 
845 	psw_set_key(PAGE_DEFAULT_KEY);
846 
847 	/* Only cosmetics */
848 	memblock_enforce_memory_limit(memblock_end_of_DRAM());
849 }
850 
851 /*
852  * Setup hardware capabilities.
853  */
854 static int __init setup_hwcaps(void)
855 {
856 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
857 	struct cpuid cpu_id;
858 	int i;
859 
860 	/*
861 	 * The store facility list bits numbers as found in the principles
862 	 * of operation are numbered with bit 1UL<<31 as number 0 to
863 	 * bit 1UL<<0 as number 31.
864 	 *   Bit 0: instructions named N3, "backported" to esa-mode
865 	 *   Bit 2: z/Architecture mode is active
866 	 *   Bit 7: the store-facility-list-extended facility is installed
867 	 *   Bit 17: the message-security assist is installed
868 	 *   Bit 19: the long-displacement facility is installed
869 	 *   Bit 21: the extended-immediate facility is installed
870 	 *   Bit 22: extended-translation facility 3 is installed
871 	 *   Bit 30: extended-translation facility 3 enhancement facility
872 	 * These get translated to:
873 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
874 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
875 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
876 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
877 	 */
878 	for (i = 0; i < 6; i++)
879 		if (test_facility(stfl_bits[i]))
880 			elf_hwcap |= 1UL << i;
881 
882 	if (test_facility(22) && test_facility(30))
883 		elf_hwcap |= HWCAP_S390_ETF3EH;
884 
885 	/*
886 	 * Check for additional facilities with store-facility-list-extended.
887 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
888 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
889 	 * as stored by stfl, bits 32-xxx contain additional facilities.
890 	 * How many facility words are stored depends on the number of
891 	 * doublewords passed to the instruction. The additional facilities
892 	 * are:
893 	 *   Bit 42: decimal floating point facility is installed
894 	 *   Bit 44: perform floating point operation facility is installed
895 	 * translated to:
896 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
897 	 */
898 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
899 		elf_hwcap |= HWCAP_S390_DFP;
900 
901 	/*
902 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
903 	 */
904 	if (MACHINE_HAS_EDAT1)
905 		elf_hwcap |= HWCAP_S390_HPAGE;
906 
907 	/*
908 	 * 64-bit register support for 31-bit processes
909 	 * HWCAP_S390_HIGH_GPRS is bit 9.
910 	 */
911 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
912 
913 	/*
914 	 * Transactional execution support HWCAP_S390_TE is bit 10.
915 	 */
916 	if (MACHINE_HAS_TE)
917 		elf_hwcap |= HWCAP_S390_TE;
918 
919 	/*
920 	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
921 	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
922 	 * instead of facility bit 129.
923 	 */
924 	if (MACHINE_HAS_VX) {
925 		elf_hwcap |= HWCAP_S390_VXRS;
926 		if (test_facility(134))
927 			elf_hwcap |= HWCAP_S390_VXRS_EXT;
928 		if (test_facility(135))
929 			elf_hwcap |= HWCAP_S390_VXRS_BCD;
930 		if (test_facility(148))
931 			elf_hwcap |= HWCAP_S390_VXRS_EXT2;
932 		if (test_facility(152))
933 			elf_hwcap |= HWCAP_S390_VXRS_PDE;
934 	}
935 	if (test_facility(150))
936 		elf_hwcap |= HWCAP_S390_SORT;
937 	if (test_facility(151))
938 		elf_hwcap |= HWCAP_S390_DFLT;
939 
940 	/*
941 	 * Guarded storage support HWCAP_S390_GS is bit 12.
942 	 */
943 	if (MACHINE_HAS_GS)
944 		elf_hwcap |= HWCAP_S390_GS;
945 
946 	get_cpu_id(&cpu_id);
947 	add_device_randomness(&cpu_id, sizeof(cpu_id));
948 	switch (cpu_id.machine) {
949 	case 0x2064:
950 	case 0x2066:
951 	default:	/* Use "z900" as default for 64 bit kernels. */
952 		strcpy(elf_platform, "z900");
953 		break;
954 	case 0x2084:
955 	case 0x2086:
956 		strcpy(elf_platform, "z990");
957 		break;
958 	case 0x2094:
959 	case 0x2096:
960 		strcpy(elf_platform, "z9-109");
961 		break;
962 	case 0x2097:
963 	case 0x2098:
964 		strcpy(elf_platform, "z10");
965 		break;
966 	case 0x2817:
967 	case 0x2818:
968 		strcpy(elf_platform, "z196");
969 		break;
970 	case 0x2827:
971 	case 0x2828:
972 		strcpy(elf_platform, "zEC12");
973 		break;
974 	case 0x2964:
975 	case 0x2965:
976 		strcpy(elf_platform, "z13");
977 		break;
978 	case 0x3906:
979 	case 0x3907:
980 		strcpy(elf_platform, "z14");
981 		break;
982 	case 0x8561:
983 	case 0x8562:
984 		strcpy(elf_platform, "z15");
985 		break;
986 	}
987 
988 	/*
989 	 * Virtualization support HWCAP_INT_SIE is bit 0.
990 	 */
991 	if (sclp.has_sief2)
992 		int_hwcap |= HWCAP_INT_SIE;
993 
994 	return 0;
995 }
996 arch_initcall(setup_hwcaps);
997 
998 /*
999  * Add system information as device randomness
1000  */
1001 static void __init setup_randomness(void)
1002 {
1003 	struct sysinfo_3_2_2 *vmms;
1004 
1005 	vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
1006 							    PAGE_SIZE);
1007 	if (!vmms)
1008 		panic("Failed to allocate memory for sysinfo structure\n");
1009 
1010 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
1011 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
1012 	memblock_free((unsigned long) vmms, PAGE_SIZE);
1013 }
1014 
1015 /*
1016  * Find the correct size for the task_struct. This depends on
1017  * the size of the struct fpu at the end of the thread_struct
1018  * which is embedded in the task_struct.
1019  */
1020 static void __init setup_task_size(void)
1021 {
1022 	int task_size = sizeof(struct task_struct);
1023 
1024 	if (!MACHINE_HAS_VX) {
1025 		task_size -= sizeof(__vector128) * __NUM_VXRS;
1026 		task_size += sizeof(freg_t) * __NUM_FPRS;
1027 	}
1028 	arch_task_struct_size = task_size;
1029 }
1030 
1031 /*
1032  * Issue diagnose 318 to set the control program name and
1033  * version codes.
1034  */
1035 static void __init setup_control_program_code(void)
1036 {
1037 	union diag318_info diag318_info = {
1038 		.cpnc = CPNC_LINUX,
1039 		.cpvc = 0,
1040 	};
1041 
1042 	if (!sclp.has_diag318)
1043 		return;
1044 
1045 	diag_stat_inc(DIAG_STAT_X318);
1046 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1047 }
1048 
1049 /*
1050  * Print the component list from the IPL report
1051  */
1052 static void __init log_component_list(void)
1053 {
1054 	struct ipl_rb_component_entry *ptr, *end;
1055 	char *str;
1056 
1057 	if (!early_ipl_comp_list_addr)
1058 		return;
1059 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
1060 		pr_info("Linux is running with Secure-IPL enabled\n");
1061 	else
1062 		pr_info("Linux is running with Secure-IPL disabled\n");
1063 	ptr = (void *) early_ipl_comp_list_addr;
1064 	end = (void *) ptr + early_ipl_comp_list_size;
1065 	pr_info("The IPL report contains the following components:\n");
1066 	while (ptr < end) {
1067 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
1068 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
1069 				str = "signed, verified";
1070 			else
1071 				str = "signed, verification failed";
1072 		} else {
1073 			str = "not signed";
1074 		}
1075 		pr_info("%016llx - %016llx (%s)\n",
1076 			ptr->addr, ptr->addr + ptr->len, str);
1077 		ptr++;
1078 	}
1079 }
1080 
1081 /*
1082  * Setup function called from init/main.c just after the banner
1083  * was printed.
1084  */
1085 
1086 void __init setup_arch(char **cmdline_p)
1087 {
1088         /*
1089          * print what head.S has found out about the machine
1090          */
1091 	if (MACHINE_IS_VM)
1092 		pr_info("Linux is running as a z/VM "
1093 			"guest operating system in 64-bit mode\n");
1094 	else if (MACHINE_IS_KVM)
1095 		pr_info("Linux is running under KVM in 64-bit mode\n");
1096 	else if (MACHINE_IS_LPAR)
1097 		pr_info("Linux is running natively in 64-bit mode\n");
1098 	else
1099 		pr_info("Linux is running as a guest in 64-bit mode\n");
1100 
1101 	log_component_list();
1102 
1103 	/* Have one command line that is parsed and saved in /proc/cmdline */
1104 	/* boot_command_line has been already set up in early.c */
1105 	*cmdline_p = boot_command_line;
1106 
1107         ROOT_DEV = Root_RAM0;
1108 
1109 	init_mm.start_code = (unsigned long) _text;
1110 	init_mm.end_code = (unsigned long) _etext;
1111 	init_mm.end_data = (unsigned long) _edata;
1112 	init_mm.brk = (unsigned long) _end;
1113 
1114 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1115 		nospec_auto_detect();
1116 
1117 	jump_label_init();
1118 	parse_early_param();
1119 #ifdef CONFIG_CRASH_DUMP
1120 	/* Deactivate elfcorehdr= kernel parameter */
1121 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
1122 #endif
1123 
1124 	os_info_init();
1125 	setup_ipl();
1126 	setup_task_size();
1127 	setup_control_program_code();
1128 
1129 	/* Do some memory reservations *before* memory is added to memblock */
1130 	reserve_above_ident_map();
1131 	reserve_oldmem();
1132 	reserve_kernel();
1133 	reserve_initrd();
1134 	reserve_certificate_list();
1135 	reserve_mem_detect_info();
1136 	memblock_allow_resize();
1137 
1138 	/* Get information about *all* installed memory */
1139 	memblock_add_mem_detect_info();
1140 
1141 	free_mem_detect_info();
1142 	remove_oldmem();
1143 
1144 	setup_uv();
1145 	setup_ident_map_size();
1146 	setup_memory();
1147 	dma_contiguous_reserve(ident_map_size);
1148 	vmcp_cma_reserve();
1149 	if (MACHINE_HAS_EDAT2)
1150 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
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 zfcp/nvme dump support */
1191 	setup_zfcpdump();
1192 
1193 	/* Add system specific data to the random pool */
1194 	setup_randomness();
1195 }
1196