xref: /openbmc/linux/arch/s390/kernel/setup.c (revision e7bae9bb)
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 | PSW_MASK_MCHECK;
385 	lc->svc_new_psw.addr = (unsigned long) system_call;
386 	lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
387 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
388 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
389 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
390 	lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
391 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
392 	lc->clock_comparator = clock_comparator_max;
393 	lc->nodat_stack = ((unsigned long) &init_thread_union)
394 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
395 	lc->current_task = (unsigned long)&init_task;
396 	lc->lpp = LPP_MAGIC;
397 	lc->machine_flags = S390_lowcore.machine_flags;
398 	lc->preempt_count = S390_lowcore.preempt_count;
399 	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
400 	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
401 	       sizeof(lc->stfle_fac_list));
402 	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
403 	       sizeof(lc->alt_stfle_fac_list));
404 	nmi_alloc_boot_cpu(lc);
405 	vdso_alloc_boot_cpu(lc);
406 	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
407 	lc->async_enter_timer = S390_lowcore.async_enter_timer;
408 	lc->exit_timer = S390_lowcore.exit_timer;
409 	lc->user_timer = S390_lowcore.user_timer;
410 	lc->system_timer = S390_lowcore.system_timer;
411 	lc->steal_timer = S390_lowcore.steal_timer;
412 	lc->last_update_timer = S390_lowcore.last_update_timer;
413 	lc->last_update_clock = S390_lowcore.last_update_clock;
414 
415 	/*
416 	 * Allocate the global restart stack which is the same for
417 	 * all CPUs in cast *one* of them does a PSW restart.
418 	 */
419 	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
420 	if (!restart_stack)
421 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
422 		      __func__, THREAD_SIZE, THREAD_SIZE);
423 	restart_stack += STACK_INIT_OFFSET;
424 
425 	/*
426 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
427 	 * restart data to the absolute zero lowcore. This is necessary if
428 	 * PSW restart is done on an offline CPU that has lowcore zero.
429 	 */
430 	lc->restart_stack = (unsigned long) restart_stack;
431 	lc->restart_fn = (unsigned long) do_restart;
432 	lc->restart_data = 0;
433 	lc->restart_source = -1UL;
434 
435 	/* Setup absolute zero lowcore */
436 	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
437 	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
438 	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
439 	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
440 	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
441 
442 	lc->spinlock_lockval = arch_spin_lockval(0);
443 	lc->spinlock_index = 0;
444 	arch_spin_lock_setup(0);
445 	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
446 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
447 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
448 
449 	set_prefix((u32)(unsigned long) lc);
450 	lowcore_ptr[0] = lc;
451 }
452 
453 static void __init setup_lowcore_dat_on(void)
454 {
455 	__ctl_clear_bit(0, 28);
456 	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
457 	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
458 	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
459 	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
460 	__ctl_set_bit(0, 28);
461 }
462 
463 static struct resource code_resource = {
464 	.name  = "Kernel code",
465 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
466 };
467 
468 static struct resource data_resource = {
469 	.name = "Kernel data",
470 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
471 };
472 
473 static struct resource bss_resource = {
474 	.name = "Kernel bss",
475 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
476 };
477 
478 static struct resource __initdata *standard_resources[] = {
479 	&code_resource,
480 	&data_resource,
481 	&bss_resource,
482 };
483 
484 static void __init setup_resources(void)
485 {
486 	struct resource *res, *std_res, *sub_res;
487 	struct memblock_region *reg;
488 	int j;
489 
490 	code_resource.start = (unsigned long) _text;
491 	code_resource.end = (unsigned long) _etext - 1;
492 	data_resource.start = (unsigned long) _etext;
493 	data_resource.end = (unsigned long) _edata - 1;
494 	bss_resource.start = (unsigned long) __bss_start;
495 	bss_resource.end = (unsigned long) __bss_stop - 1;
496 
497 	for_each_memblock(memory, reg) {
498 		res = memblock_alloc(sizeof(*res), 8);
499 		if (!res)
500 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
501 			      __func__, sizeof(*res), 8);
502 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
503 
504 		res->name = "System RAM";
505 		res->start = reg->base;
506 		res->end = reg->base + reg->size - 1;
507 		request_resource(&iomem_resource, res);
508 
509 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
510 			std_res = standard_resources[j];
511 			if (std_res->start < res->start ||
512 			    std_res->start > res->end)
513 				continue;
514 			if (std_res->end > res->end) {
515 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
516 				if (!sub_res)
517 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
518 					      __func__, sizeof(*sub_res), 8);
519 				*sub_res = *std_res;
520 				sub_res->end = res->end;
521 				std_res->start = res->end + 1;
522 				request_resource(res, sub_res);
523 			} else {
524 				request_resource(res, std_res);
525 			}
526 		}
527 	}
528 #ifdef CONFIG_CRASH_DUMP
529 	/*
530 	 * Re-add removed crash kernel memory as reserved memory. This makes
531 	 * sure it will be mapped with the identity mapping and struct pages
532 	 * will be created, so it can be resized later on.
533 	 * However add it later since the crash kernel resource should not be
534 	 * part of the System RAM resource.
535 	 */
536 	if (crashk_res.end) {
537 		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
538 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
539 		insert_resource(&iomem_resource, &crashk_res);
540 	}
541 #endif
542 }
543 
544 static void __init setup_memory_end(void)
545 {
546 	unsigned long vmax, tmp;
547 
548 	/* Choose kernel address space layout: 3 or 4 levels. */
549 	if (IS_ENABLED(CONFIG_KASAN)) {
550 		vmax = IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)
551 			   ? _REGION1_SIZE
552 			   : _REGION2_SIZE;
553 	} else {
554 		tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
555 		tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
556 		if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
557 			vmax = _REGION2_SIZE; /* 3-level kernel page table */
558 		else
559 			vmax = _REGION1_SIZE; /* 4-level kernel page table */
560 	}
561 
562 	if (is_prot_virt_host())
563 		adjust_to_uv_max(&vmax);
564 
565 	/* module area is at the end of the kernel address space. */
566 	MODULES_END = vmax;
567 	MODULES_VADDR = MODULES_END - MODULES_LEN;
568 	VMALLOC_END = MODULES_VADDR;
569 	VMALLOC_START = VMALLOC_END - vmalloc_size;
570 
571 	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
572 	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
573 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
574 	tmp = SECTION_ALIGN_UP(tmp);
575 	tmp = VMALLOC_START - tmp * sizeof(struct page);
576 	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
577 	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
578 	vmemmap = (struct page *) tmp;
579 
580 	/* Take care that memory_end is set and <= vmemmap */
581 	memory_end = min(memory_end ?: max_physmem_end, (unsigned long)vmemmap);
582 #ifdef CONFIG_KASAN
583 	/* fit in kasan shadow memory region between 1:1 and vmemmap */
584 	memory_end = min(memory_end, KASAN_SHADOW_START);
585 	vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
586 #endif
587 	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
588 	memblock_remove(memory_end, ULONG_MAX);
589 
590 	pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
591 }
592 
593 #ifdef CONFIG_CRASH_DUMP
594 
595 /*
596  * When kdump is enabled, we have to ensure that no memory from the area
597  * [0 - crashkernel memory size] is set offline - it will be exchanged with
598  * the crashkernel memory region when kdump is triggered. The crashkernel
599  * memory region can never get offlined (pages are unmovable).
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 	return NOTIFY_OK;
611 }
612 
613 static struct notifier_block kdump_mem_nb = {
614 	.notifier_call = kdump_mem_notifier,
615 };
616 
617 #endif
618 
619 /*
620  * Make sure that the area behind memory_end is protected
621  */
622 static void __init reserve_memory_end(void)
623 {
624 	if (memory_end_set)
625 		memblock_reserve(memory_end, ULONG_MAX);
626 }
627 
628 /*
629  * Make sure that oldmem, where the dump is stored, is protected
630  */
631 static void __init reserve_oldmem(void)
632 {
633 #ifdef CONFIG_CRASH_DUMP
634 	if (OLDMEM_BASE)
635 		/* Forget all memory above the running kdump system */
636 		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
637 #endif
638 }
639 
640 /*
641  * Make sure that oldmem, where the dump is stored, is protected
642  */
643 static void __init remove_oldmem(void)
644 {
645 #ifdef CONFIG_CRASH_DUMP
646 	if (OLDMEM_BASE)
647 		/* Forget all memory above the running kdump system */
648 		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
649 #endif
650 }
651 
652 /*
653  * Reserve memory for kdump kernel to be loaded with kexec
654  */
655 static void __init reserve_crashkernel(void)
656 {
657 #ifdef CONFIG_CRASH_DUMP
658 	unsigned long long crash_base, crash_size;
659 	phys_addr_t low, high;
660 	int rc;
661 
662 	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
663 			       &crash_base);
664 
665 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
666 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
667 	if (rc || crash_size == 0)
668 		return;
669 
670 	if (memblock.memory.regions[0].size < crash_size) {
671 		pr_info("crashkernel reservation failed: %s\n",
672 			"first memory chunk must be at least crashkernel size");
673 		return;
674 	}
675 
676 	low = crash_base ?: OLDMEM_BASE;
677 	high = low + crash_size;
678 	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
679 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
680 		crash_base = low;
681 	} else {
682 		/* Find suitable area in free memory */
683 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
684 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
685 
686 		if (crash_base && crash_base < low) {
687 			pr_info("crashkernel reservation failed: %s\n",
688 				"crash_base too low");
689 			return;
690 		}
691 		low = crash_base ?: low;
692 		crash_base = memblock_find_in_range(low, high, crash_size,
693 						    KEXEC_CRASH_MEM_ALIGN);
694 	}
695 
696 	if (!crash_base) {
697 		pr_info("crashkernel reservation failed: %s\n",
698 			"no suitable area found");
699 		return;
700 	}
701 
702 	if (register_memory_notifier(&kdump_mem_nb))
703 		return;
704 
705 	if (!OLDMEM_BASE && MACHINE_IS_VM)
706 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
707 	crashk_res.start = crash_base;
708 	crashk_res.end = crash_base + crash_size - 1;
709 	memblock_remove(crash_base, crash_size);
710 	pr_info("Reserving %lluMB of memory at %lluMB "
711 		"for crashkernel (System RAM: %luMB)\n",
712 		crash_size >> 20, crash_base >> 20,
713 		(unsigned long)memblock.memory.total_size >> 20);
714 	os_info_crashkernel_add(crash_base, crash_size);
715 #endif
716 }
717 
718 /*
719  * Reserve the initrd from being used by memblock
720  */
721 static void __init reserve_initrd(void)
722 {
723 #ifdef CONFIG_BLK_DEV_INITRD
724 	if (!INITRD_START || !INITRD_SIZE)
725 		return;
726 	initrd_start = INITRD_START;
727 	initrd_end = initrd_start + INITRD_SIZE;
728 	memblock_reserve(INITRD_START, INITRD_SIZE);
729 #endif
730 }
731 
732 /*
733  * Reserve the memory area used to pass the certificate lists
734  */
735 static void __init reserve_certificate_list(void)
736 {
737 	if (ipl_cert_list_addr)
738 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
739 }
740 
741 static void __init reserve_mem_detect_info(void)
742 {
743 	unsigned long start, size;
744 
745 	get_mem_detect_reserved(&start, &size);
746 	if (size)
747 		memblock_reserve(start, size);
748 }
749 
750 static void __init free_mem_detect_info(void)
751 {
752 	unsigned long start, size;
753 
754 	get_mem_detect_reserved(&start, &size);
755 	if (size)
756 		memblock_free(start, size);
757 }
758 
759 static const char * __init get_mem_info_source(void)
760 {
761 	switch (mem_detect.info_source) {
762 	case MEM_DETECT_SCLP_STOR_INFO:
763 		return "sclp storage info";
764 	case MEM_DETECT_DIAG260:
765 		return "diag260";
766 	case MEM_DETECT_SCLP_READ_INFO:
767 		return "sclp read info";
768 	case MEM_DETECT_BIN_SEARCH:
769 		return "binary search";
770 	}
771 	return "none";
772 }
773 
774 static void __init memblock_add_mem_detect_info(void)
775 {
776 	unsigned long start, end;
777 	int i;
778 
779 	memblock_dbg("physmem info source: %s (%hhd)\n",
780 		     get_mem_info_source(), mem_detect.info_source);
781 	/* keep memblock lists close to the kernel */
782 	memblock_set_bottom_up(true);
783 	for_each_mem_detect_block(i, &start, &end) {
784 		memblock_add(start, end - start);
785 		memblock_physmem_add(start, end - start);
786 	}
787 	memblock_set_bottom_up(false);
788 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
789 	memblock_dump_all();
790 }
791 
792 /*
793  * Check for initrd being in usable memory
794  */
795 static void __init check_initrd(void)
796 {
797 #ifdef CONFIG_BLK_DEV_INITRD
798 	if (INITRD_START && INITRD_SIZE &&
799 	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
800 		pr_err("The initial RAM disk does not fit into the memory\n");
801 		memblock_free(INITRD_START, INITRD_SIZE);
802 		initrd_start = initrd_end = 0;
803 	}
804 #endif
805 }
806 
807 /*
808  * Reserve memory used for lowcore/command line/kernel image.
809  */
810 static void __init reserve_kernel(void)
811 {
812 	unsigned long start_pfn = PFN_UP(__pa(_end));
813 
814 	memblock_reserve(0, HEAD_END);
815 	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
816 			 - (unsigned long)_stext);
817 	memblock_reserve(__sdma, __edma - __sdma);
818 }
819 
820 static void __init setup_memory(void)
821 {
822 	struct memblock_region *reg;
823 
824 	/*
825 	 * Init storage key for present memory
826 	 */
827 	for_each_memblock(memory, reg) {
828 		storage_key_init_range(reg->base, reg->base + reg->size);
829 	}
830 	psw_set_key(PAGE_DEFAULT_KEY);
831 
832 	/* Only cosmetics */
833 	memblock_enforce_memory_limit(memblock_end_of_DRAM());
834 }
835 
836 /*
837  * Setup hardware capabilities.
838  */
839 static int __init setup_hwcaps(void)
840 {
841 	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
842 	struct cpuid cpu_id;
843 	int i;
844 
845 	/*
846 	 * The store facility list bits numbers as found in the principles
847 	 * of operation are numbered with bit 1UL<<31 as number 0 to
848 	 * bit 1UL<<0 as number 31.
849 	 *   Bit 0: instructions named N3, "backported" to esa-mode
850 	 *   Bit 2: z/Architecture mode is active
851 	 *   Bit 7: the store-facility-list-extended facility is installed
852 	 *   Bit 17: the message-security assist is installed
853 	 *   Bit 19: the long-displacement facility is installed
854 	 *   Bit 21: the extended-immediate facility is installed
855 	 *   Bit 22: extended-translation facility 3 is installed
856 	 *   Bit 30: extended-translation facility 3 enhancement facility
857 	 * These get translated to:
858 	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
859 	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
860 	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
861 	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
862 	 */
863 	for (i = 0; i < 6; i++)
864 		if (test_facility(stfl_bits[i]))
865 			elf_hwcap |= 1UL << i;
866 
867 	if (test_facility(22) && test_facility(30))
868 		elf_hwcap |= HWCAP_S390_ETF3EH;
869 
870 	/*
871 	 * Check for additional facilities with store-facility-list-extended.
872 	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
873 	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
874 	 * as stored by stfl, bits 32-xxx contain additional facilities.
875 	 * How many facility words are stored depends on the number of
876 	 * doublewords passed to the instruction. The additional facilities
877 	 * are:
878 	 *   Bit 42: decimal floating point facility is installed
879 	 *   Bit 44: perform floating point operation facility is installed
880 	 * translated to:
881 	 *   HWCAP_S390_DFP bit 6 (42 && 44).
882 	 */
883 	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
884 		elf_hwcap |= HWCAP_S390_DFP;
885 
886 	/*
887 	 * Huge page support HWCAP_S390_HPAGE is bit 7.
888 	 */
889 	if (MACHINE_HAS_EDAT1)
890 		elf_hwcap |= HWCAP_S390_HPAGE;
891 
892 	/*
893 	 * 64-bit register support for 31-bit processes
894 	 * HWCAP_S390_HIGH_GPRS is bit 9.
895 	 */
896 	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
897 
898 	/*
899 	 * Transactional execution support HWCAP_S390_TE is bit 10.
900 	 */
901 	if (MACHINE_HAS_TE)
902 		elf_hwcap |= HWCAP_S390_TE;
903 
904 	/*
905 	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
906 	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
907 	 * instead of facility bit 129.
908 	 */
909 	if (MACHINE_HAS_VX) {
910 		elf_hwcap |= HWCAP_S390_VXRS;
911 		if (test_facility(134))
912 			elf_hwcap |= HWCAP_S390_VXRS_EXT;
913 		if (test_facility(135))
914 			elf_hwcap |= HWCAP_S390_VXRS_BCD;
915 		if (test_facility(148))
916 			elf_hwcap |= HWCAP_S390_VXRS_EXT2;
917 		if (test_facility(152))
918 			elf_hwcap |= HWCAP_S390_VXRS_PDE;
919 	}
920 	if (test_facility(150))
921 		elf_hwcap |= HWCAP_S390_SORT;
922 	if (test_facility(151))
923 		elf_hwcap |= HWCAP_S390_DFLT;
924 
925 	/*
926 	 * Guarded storage support HWCAP_S390_GS is bit 12.
927 	 */
928 	if (MACHINE_HAS_GS)
929 		elf_hwcap |= HWCAP_S390_GS;
930 
931 	get_cpu_id(&cpu_id);
932 	add_device_randomness(&cpu_id, sizeof(cpu_id));
933 	switch (cpu_id.machine) {
934 	case 0x2064:
935 	case 0x2066:
936 	default:	/* Use "z900" as default for 64 bit kernels. */
937 		strcpy(elf_platform, "z900");
938 		break;
939 	case 0x2084:
940 	case 0x2086:
941 		strcpy(elf_platform, "z990");
942 		break;
943 	case 0x2094:
944 	case 0x2096:
945 		strcpy(elf_platform, "z9-109");
946 		break;
947 	case 0x2097:
948 	case 0x2098:
949 		strcpy(elf_platform, "z10");
950 		break;
951 	case 0x2817:
952 	case 0x2818:
953 		strcpy(elf_platform, "z196");
954 		break;
955 	case 0x2827:
956 	case 0x2828:
957 		strcpy(elf_platform, "zEC12");
958 		break;
959 	case 0x2964:
960 	case 0x2965:
961 		strcpy(elf_platform, "z13");
962 		break;
963 	case 0x3906:
964 	case 0x3907:
965 		strcpy(elf_platform, "z14");
966 		break;
967 	case 0x8561:
968 	case 0x8562:
969 		strcpy(elf_platform, "z15");
970 		break;
971 	}
972 
973 	/*
974 	 * Virtualization support HWCAP_INT_SIE is bit 0.
975 	 */
976 	if (sclp.has_sief2)
977 		int_hwcap |= HWCAP_INT_SIE;
978 
979 	return 0;
980 }
981 arch_initcall(setup_hwcaps);
982 
983 /*
984  * Add system information as device randomness
985  */
986 static void __init setup_randomness(void)
987 {
988 	struct sysinfo_3_2_2 *vmms;
989 
990 	vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
991 							    PAGE_SIZE);
992 	if (!vmms)
993 		panic("Failed to allocate memory for sysinfo structure\n");
994 
995 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
996 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
997 	memblock_free((unsigned long) vmms, PAGE_SIZE);
998 }
999 
1000 /*
1001  * Find the correct size for the task_struct. This depends on
1002  * the size of the struct fpu at the end of the thread_struct
1003  * which is embedded in the task_struct.
1004  */
1005 static void __init setup_task_size(void)
1006 {
1007 	int task_size = sizeof(struct task_struct);
1008 
1009 	if (!MACHINE_HAS_VX) {
1010 		task_size -= sizeof(__vector128) * __NUM_VXRS;
1011 		task_size += sizeof(freg_t) * __NUM_FPRS;
1012 	}
1013 	arch_task_struct_size = task_size;
1014 }
1015 
1016 /*
1017  * Issue diagnose 318 to set the control program name and
1018  * version codes.
1019  */
1020 static void __init setup_control_program_code(void)
1021 {
1022 	union diag318_info diag318_info = {
1023 		.cpnc = CPNC_LINUX,
1024 		.cpvc = 0,
1025 	};
1026 
1027 	if (!sclp.has_diag318)
1028 		return;
1029 
1030 	diag_stat_inc(DIAG_STAT_X318);
1031 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1032 }
1033 
1034 /*
1035  * Print the component list from the IPL report
1036  */
1037 static void __init log_component_list(void)
1038 {
1039 	struct ipl_rb_component_entry *ptr, *end;
1040 	char *str;
1041 
1042 	if (!early_ipl_comp_list_addr)
1043 		return;
1044 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
1045 		pr_info("Linux is running with Secure-IPL enabled\n");
1046 	else
1047 		pr_info("Linux is running with Secure-IPL disabled\n");
1048 	ptr = (void *) early_ipl_comp_list_addr;
1049 	end = (void *) ptr + early_ipl_comp_list_size;
1050 	pr_info("The IPL report contains the following components:\n");
1051 	while (ptr < end) {
1052 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
1053 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
1054 				str = "signed, verified";
1055 			else
1056 				str = "signed, verification failed";
1057 		} else {
1058 			str = "not signed";
1059 		}
1060 		pr_info("%016llx - %016llx (%s)\n",
1061 			ptr->addr, ptr->addr + ptr->len, str);
1062 		ptr++;
1063 	}
1064 }
1065 
1066 /*
1067  * Setup function called from init/main.c just after the banner
1068  * was printed.
1069  */
1070 
1071 void __init setup_arch(char **cmdline_p)
1072 {
1073         /*
1074          * print what head.S has found out about the machine
1075          */
1076 	if (MACHINE_IS_VM)
1077 		pr_info("Linux is running as a z/VM "
1078 			"guest operating system in 64-bit mode\n");
1079 	else if (MACHINE_IS_KVM)
1080 		pr_info("Linux is running under KVM in 64-bit mode\n");
1081 	else if (MACHINE_IS_LPAR)
1082 		pr_info("Linux is running natively in 64-bit mode\n");
1083 	else
1084 		pr_info("Linux is running as a guest in 64-bit mode\n");
1085 
1086 	log_component_list();
1087 
1088 	/* Have one command line that is parsed and saved in /proc/cmdline */
1089 	/* boot_command_line has been already set up in early.c */
1090 	*cmdline_p = boot_command_line;
1091 
1092         ROOT_DEV = Root_RAM0;
1093 
1094 	init_mm.start_code = (unsigned long) _text;
1095 	init_mm.end_code = (unsigned long) _etext;
1096 	init_mm.end_data = (unsigned long) _edata;
1097 	init_mm.brk = (unsigned long) _end;
1098 
1099 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1100 		nospec_auto_detect();
1101 
1102 	jump_label_init();
1103 	parse_early_param();
1104 #ifdef CONFIG_CRASH_DUMP
1105 	/* Deactivate elfcorehdr= kernel parameter */
1106 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
1107 #endif
1108 
1109 	os_info_init();
1110 	setup_ipl();
1111 	setup_task_size();
1112 	setup_control_program_code();
1113 
1114 	/* Do some memory reservations *before* memory is added to memblock */
1115 	reserve_memory_end();
1116 	reserve_oldmem();
1117 	reserve_kernel();
1118 	reserve_initrd();
1119 	reserve_certificate_list();
1120 	reserve_mem_detect_info();
1121 	memblock_allow_resize();
1122 
1123 	/* Get information about *all* installed memory */
1124 	memblock_add_mem_detect_info();
1125 
1126 	free_mem_detect_info();
1127 	remove_oldmem();
1128 
1129 	if (is_prot_virt_host())
1130 		setup_uv();
1131 	setup_memory_end();
1132 	setup_memory();
1133 	dma_contiguous_reserve(memory_end);
1134 	vmcp_cma_reserve();
1135 
1136 	check_initrd();
1137 	reserve_crashkernel();
1138 #ifdef CONFIG_CRASH_DUMP
1139 	/*
1140 	 * Be aware that smp_save_dump_cpus() triggers a system reset.
1141 	 * Therefore CPU and device initialization should be done afterwards.
1142 	 */
1143 	smp_save_dump_cpus();
1144 #endif
1145 
1146 	setup_resources();
1147 	setup_lowcore_dat_off();
1148 	smp_fill_possible_mask();
1149 	cpu_detect_mhz_feature();
1150         cpu_init();
1151 	numa_setup();
1152 	smp_detect_cpus();
1153 	topology_init_early();
1154 
1155 	/*
1156 	 * Create kernel page tables and switch to virtual addressing.
1157 	 */
1158         paging_init();
1159 
1160 	/*
1161 	 * After paging_init created the kernel page table, the new PSWs
1162 	 * in lowcore can now run with DAT enabled.
1163 	 */
1164 	setup_lowcore_dat_on();
1165 
1166         /* Setup default console */
1167 	conmode_default();
1168 	set_preferred_console();
1169 
1170 	apply_alternative_instructions();
1171 	if (IS_ENABLED(CONFIG_EXPOLINE))
1172 		nospec_init_branches();
1173 
1174 	/* Setup zfcpdump support */
1175 	setup_zfcpdump();
1176 
1177 	/* Add system specific data to the random pool */
1178 	setup_randomness();
1179 }
1180