xref: /linux/arch/s390/kernel/setup.c (revision 48fb4b3d9b43ea8f81de06f12f83912f8c1d5a15)
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 #include <linux/kmemleak.h>
54 
55 #include <asm/archrandom.h>
56 #include <asm/boot_data.h>
57 #include <asm/ipl.h>
58 #include <asm/facility.h>
59 #include <asm/smp.h>
60 #include <asm/mmu_context.h>
61 #include <asm/cpcmd.h>
62 #include <asm/abs_lowcore.h>
63 #include <asm/nmi.h>
64 #include <asm/irq.h>
65 #include <asm/page.h>
66 #include <asm/ptrace.h>
67 #include <asm/sections.h>
68 #include <asm/ebcdic.h>
69 #include <asm/diag.h>
70 #include <asm/os_info.h>
71 #include <asm/sclp.h>
72 #include <asm/stacktrace.h>
73 #include <asm/sysinfo.h>
74 #include <asm/numa.h>
75 #include <asm/alternative.h>
76 #include <asm/nospec-branch.h>
77 #include <asm/physmem_info.h>
78 #include <asm/maccess.h>
79 #include <asm/uv.h>
80 #include <asm/asm-offsets.h>
81 #include "entry.h"
82 
83 /*
84  * Machine setup..
85  */
86 unsigned int console_mode = 0;
87 EXPORT_SYMBOL(console_mode);
88 
89 unsigned int console_devno = -1;
90 EXPORT_SYMBOL(console_devno);
91 
92 unsigned int console_irq = -1;
93 EXPORT_SYMBOL(console_irq);
94 
95 /*
96  * Some code and data needs to stay below 2 GB, even when the kernel would be
97  * relocated above 2 GB, because it has to use 31 bit addresses.
98  * Such code and data is part of the .amode31 section.
99  */
100 char __amode31_ref *__samode31 = _samode31;
101 char __amode31_ref *__eamode31 = _eamode31;
102 char __amode31_ref *__stext_amode31 = _stext_amode31;
103 char __amode31_ref *__etext_amode31 = _etext_amode31;
104 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
105 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
106 
107 /*
108  * Control registers CR2, CR5 and CR15 are initialized with addresses
109  * of tables that must be placed below 2G which is handled by the AMODE31
110  * sections.
111  * Because the AMODE31 sections are relocated below 2G at startup,
112  * the content of control registers CR2, CR5 and CR15 must be updated
113  * with new addresses after the relocation. The initial initialization of
114  * control registers occurs in head64.S and then gets updated again after AMODE31
115  * relocation. We must access the relevant AMODE31 tables indirectly via
116  * pointers placed in the .amode31.refs linker section. Those pointers get
117  * updated automatically during AMODE31 relocation and always contain a valid
118  * address within AMODE31 sections.
119  */
120 
121 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
122 
123 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
124 	[1] = 0xffffffffffffffff
125 };
126 
127 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
128 	0x80000000, 0, 0, 0,
129 	0x80000000, 0, 0, 0,
130 	0x80000000, 0, 0, 0,
131 	0x80000000, 0, 0, 0,
132 	0x80000000, 0, 0, 0,
133 	0x80000000, 0, 0, 0,
134 	0x80000000, 0, 0, 0,
135 	0x80000000, 0, 0, 0
136 };
137 
138 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
139 	0, 0, 0x89000000, 0,
140 	0, 0, 0x8a000000, 0
141 };
142 
143 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
144 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
145 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
146 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
147 
148 unsigned long __bootdata_preserved(max_mappable);
149 struct physmem_info __bootdata(physmem_info);
150 
151 struct vm_layout __bootdata_preserved(vm_layout);
152 EXPORT_SYMBOL(vm_layout);
153 int __bootdata_preserved(__kaslr_enabled);
154 unsigned int __bootdata_preserved(zlib_dfltcc_support);
155 EXPORT_SYMBOL(zlib_dfltcc_support);
156 u64 __bootdata_preserved(stfle_fac_list[16]);
157 EXPORT_SYMBOL(stfle_fac_list);
158 struct oldmem_data __bootdata_preserved(oldmem_data);
159 
160 unsigned long VMALLOC_START;
161 EXPORT_SYMBOL(VMALLOC_START);
162 
163 unsigned long VMALLOC_END;
164 EXPORT_SYMBOL(VMALLOC_END);
165 
166 struct page *vmemmap;
167 EXPORT_SYMBOL(vmemmap);
168 unsigned long vmemmap_size;
169 
170 unsigned long MODULES_VADDR;
171 unsigned long MODULES_END;
172 
173 /* An array with a pointer to the lowcore of every CPU. */
174 struct lowcore *lowcore_ptr[NR_CPUS];
175 EXPORT_SYMBOL(lowcore_ptr);
176 
177 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
178 
179 /*
180  * The Write Back bit position in the physaddr is given by the SLPC PCI.
181  * Leaving the mask zero always uses write through which is safe
182  */
183 unsigned long mio_wb_bit_mask __ro_after_init;
184 
185 /*
186  * This is set up by the setup-routine at boot-time
187  * for S390 need to find out, what we have to setup
188  * using address 0x10400 ...
189  */
190 
191 #include <asm/setup.h>
192 
193 /*
194  * condev= and conmode= setup parameter.
195  */
196 
condev_setup(char * str)197 static int __init condev_setup(char *str)
198 {
199 	int vdev;
200 
201 	vdev = simple_strtoul(str, &str, 0);
202 	if (vdev >= 0 && vdev < 65536) {
203 		console_devno = vdev;
204 		console_irq = -1;
205 	}
206 	return 1;
207 }
208 
209 __setup("condev=", condev_setup);
210 
set_preferred_console(void)211 static void __init set_preferred_console(void)
212 {
213 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
214 		add_preferred_console("ttyS", 0, NULL);
215 	else if (CONSOLE_IS_3270)
216 		add_preferred_console("tty3270", 0, NULL);
217 	else if (CONSOLE_IS_VT220)
218 		add_preferred_console("ttysclp", 0, NULL);
219 	else if (CONSOLE_IS_HVC)
220 		add_preferred_console("hvc", 0, NULL);
221 }
222 
conmode_setup(char * str)223 static int __init conmode_setup(char *str)
224 {
225 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
226 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
227                 SET_CONSOLE_SCLP;
228 #endif
229 #if defined(CONFIG_TN3215_CONSOLE)
230 	if (!strcmp(str, "3215"))
231 		SET_CONSOLE_3215;
232 #endif
233 #if defined(CONFIG_TN3270_CONSOLE)
234 	if (!strcmp(str, "3270"))
235 		SET_CONSOLE_3270;
236 #endif
237 	set_preferred_console();
238         return 1;
239 }
240 
241 __setup("conmode=", conmode_setup);
242 
conmode_default(void)243 static void __init conmode_default(void)
244 {
245 	char query_buffer[1024];
246 	char *ptr;
247 
248         if (MACHINE_IS_VM) {
249 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
250 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
251 		ptr = strstr(query_buffer, "SUBCHANNEL =");
252 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
253 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
254 		ptr = strstr(query_buffer, "CONMODE");
255 		/*
256 		 * Set the conmode to 3215 so that the device recognition
257 		 * will set the cu_type of the console to 3215. If the
258 		 * conmode is 3270 and we don't set it back then both
259 		 * 3215 and the 3270 driver will try to access the console
260 		 * device (3215 as console and 3270 as normal tty).
261 		 */
262 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
263 		if (ptr == NULL) {
264 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
265 			SET_CONSOLE_SCLP;
266 #endif
267 			return;
268 		}
269 		if (str_has_prefix(ptr + 8, "3270")) {
270 #if defined(CONFIG_TN3270_CONSOLE)
271 			SET_CONSOLE_3270;
272 #elif defined(CONFIG_TN3215_CONSOLE)
273 			SET_CONSOLE_3215;
274 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
275 			SET_CONSOLE_SCLP;
276 #endif
277 		} else if (str_has_prefix(ptr + 8, "3215")) {
278 #if defined(CONFIG_TN3215_CONSOLE)
279 			SET_CONSOLE_3215;
280 #elif defined(CONFIG_TN3270_CONSOLE)
281 			SET_CONSOLE_3270;
282 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
283 			SET_CONSOLE_SCLP;
284 #endif
285 		}
286 	} else if (MACHINE_IS_KVM) {
287 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
288 			SET_CONSOLE_VT220;
289 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
290 			SET_CONSOLE_SCLP;
291 		else
292 			SET_CONSOLE_HVC;
293 	} else {
294 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
295 		SET_CONSOLE_SCLP;
296 #endif
297 	}
298 }
299 
300 #ifdef CONFIG_CRASH_DUMP
setup_zfcpdump(void)301 static void __init setup_zfcpdump(void)
302 {
303 	if (!is_ipl_type_dump())
304 		return;
305 	if (oldmem_data.start)
306 		return;
307 	strlcat(boot_command_line, " cio_ignore=all,!ipldev,!condev", COMMAND_LINE_SIZE);
308 	console_loglevel = 2;
309 }
310 #else
setup_zfcpdump(void)311 static inline void setup_zfcpdump(void) {}
312 #endif /* CONFIG_CRASH_DUMP */
313 
314  /*
315  * Reboot, halt and power_off stubs. They just call _machine_restart,
316  * _machine_halt or _machine_power_off.
317  */
318 
machine_restart(char * command)319 void machine_restart(char *command)
320 {
321 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
322 		/*
323 		 * Only unblank the console if we are called in enabled
324 		 * context or a bust_spinlocks cleared the way for us.
325 		 */
326 		console_unblank();
327 	_machine_restart(command);
328 }
329 
machine_halt(void)330 void machine_halt(void)
331 {
332 	if (!in_interrupt() || oops_in_progress)
333 		/*
334 		 * Only unblank the console if we are called in enabled
335 		 * context or a bust_spinlocks cleared the way for us.
336 		 */
337 		console_unblank();
338 	_machine_halt();
339 }
340 
machine_power_off(void)341 void machine_power_off(void)
342 {
343 	if (!in_interrupt() || oops_in_progress)
344 		/*
345 		 * Only unblank the console if we are called in enabled
346 		 * context or a bust_spinlocks cleared the way for us.
347 		 */
348 		console_unblank();
349 	_machine_power_off();
350 }
351 
352 /*
353  * Dummy power off function.
354  */
355 void (*pm_power_off)(void) = machine_power_off;
356 EXPORT_SYMBOL_GPL(pm_power_off);
357 
358 void *restart_stack;
359 
stack_alloc(void)360 unsigned long stack_alloc(void)
361 {
362 #ifdef CONFIG_VMAP_STACK
363 	void *ret;
364 
365 	ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
366 			     NUMA_NO_NODE, __builtin_return_address(0));
367 	kmemleak_not_leak(ret);
368 	return (unsigned long)ret;
369 #else
370 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
371 #endif
372 }
373 
stack_free(unsigned long stack)374 void stack_free(unsigned long stack)
375 {
376 #ifdef CONFIG_VMAP_STACK
377 	vfree((void *) stack);
378 #else
379 	free_pages(stack, THREAD_SIZE_ORDER);
380 #endif
381 }
382 
stack_alloc_early(void)383 static unsigned long __init stack_alloc_early(void)
384 {
385 	unsigned long stack;
386 
387 	stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
388 	if (!stack) {
389 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
390 		      __func__, THREAD_SIZE, THREAD_SIZE);
391 	}
392 	return stack;
393 }
394 
setup_lowcore(void)395 static void __init setup_lowcore(void)
396 {
397 	struct lowcore *lc, *abs_lc;
398 
399 	/*
400 	 * Setup lowcore for boot cpu
401 	 */
402 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
403 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
404 	if (!lc)
405 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
406 		      __func__, sizeof(*lc), sizeof(*lc));
407 
408 	lc->pcpu = (unsigned long)per_cpu_ptr(&pcpu_devices, 0);
409 	lc->restart_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT;
410 	lc->restart_psw.addr = __pa(restart_int_handler);
411 	lc->external_new_psw.mask = PSW_KERNEL_BITS;
412 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
413 	lc->svc_new_psw.mask = PSW_KERNEL_BITS;
414 	lc->svc_new_psw.addr = (unsigned long) system_call;
415 	lc->program_new_psw.mask = PSW_KERNEL_BITS;
416 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
417 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
418 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
419 	lc->io_new_psw.mask = PSW_KERNEL_BITS;
420 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
421 	lc->clock_comparator = clock_comparator_max;
422 	lc->current_task = (unsigned long)&init_task;
423 	lc->lpp = LPP_MAGIC;
424 	lc->machine_flags = get_lowcore()->machine_flags;
425 	lc->preempt_count = get_lowcore()->preempt_count;
426 	nmi_alloc_mcesa_early(&lc->mcesad);
427 	lc->sys_enter_timer = get_lowcore()->sys_enter_timer;
428 	lc->exit_timer = get_lowcore()->exit_timer;
429 	lc->user_timer = get_lowcore()->user_timer;
430 	lc->system_timer = get_lowcore()->system_timer;
431 	lc->steal_timer = get_lowcore()->steal_timer;
432 	lc->last_update_timer = get_lowcore()->last_update_timer;
433 	lc->last_update_clock = get_lowcore()->last_update_clock;
434 	/*
435 	 * Allocate the global restart stack which is the same for
436 	 * all CPUs in case *one* of them does a PSW restart.
437 	 */
438 	restart_stack = (void *)(stack_alloc_early() + STACK_INIT_OFFSET);
439 	lc->mcck_stack = stack_alloc_early() + STACK_INIT_OFFSET;
440 	lc->async_stack = stack_alloc_early() + STACK_INIT_OFFSET;
441 	lc->nodat_stack = stack_alloc_early() + STACK_INIT_OFFSET;
442 	lc->kernel_stack = get_lowcore()->kernel_stack;
443 	/*
444 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
445 	 * restart data to the absolute zero lowcore. This is necessary if
446 	 * PSW restart is done on an offline CPU that has lowcore zero.
447 	 */
448 	lc->restart_stack = (unsigned long) restart_stack;
449 	lc->restart_fn = (unsigned long) do_restart;
450 	lc->restart_data = 0;
451 	lc->restart_source = -1U;
452 	lc->spinlock_lockval = arch_spin_lockval(0);
453 	lc->spinlock_index = 0;
454 	arch_spin_lock_setup(0);
455 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
456 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
457 	lc->preempt_count = PREEMPT_DISABLED;
458 	lc->kernel_asce = get_lowcore()->kernel_asce;
459 	lc->user_asce = get_lowcore()->user_asce;
460 
461 	system_ctlreg_init_save_area(lc);
462 	abs_lc = get_abs_lowcore();
463 	abs_lc->restart_stack = lc->restart_stack;
464 	abs_lc->restart_fn = lc->restart_fn;
465 	abs_lc->restart_data = lc->restart_data;
466 	abs_lc->restart_source = lc->restart_source;
467 	abs_lc->restart_psw = lc->restart_psw;
468 	abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
469 	abs_lc->program_new_psw = lc->program_new_psw;
470 	abs_lc->mcesad = lc->mcesad;
471 	put_abs_lowcore(abs_lc);
472 
473 	set_prefix(__pa(lc));
474 	lowcore_ptr[0] = lc;
475 	if (abs_lowcore_map(0, lowcore_ptr[0], false))
476 		panic("Couldn't setup absolute lowcore");
477 }
478 
479 static struct resource code_resource = {
480 	.name  = "Kernel code",
481 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
482 };
483 
484 static struct resource data_resource = {
485 	.name = "Kernel data",
486 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
487 };
488 
489 static struct resource bss_resource = {
490 	.name = "Kernel bss",
491 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
492 };
493 
494 static struct resource __initdata *standard_resources[] = {
495 	&code_resource,
496 	&data_resource,
497 	&bss_resource,
498 };
499 
setup_resources(void)500 static void __init setup_resources(void)
501 {
502 	struct resource *res, *std_res, *sub_res;
503 	phys_addr_t start, end;
504 	int j;
505 	u64 i;
506 
507 	code_resource.start = __pa_symbol(_text);
508 	code_resource.end = __pa_symbol(_etext) - 1;
509 	data_resource.start = __pa_symbol(_etext);
510 	data_resource.end = __pa_symbol(_edata) - 1;
511 	bss_resource.start = __pa_symbol(__bss_start);
512 	bss_resource.end = __pa_symbol(__bss_stop) - 1;
513 
514 	for_each_mem_range(i, &start, &end) {
515 		res = memblock_alloc(sizeof(*res), 8);
516 		if (!res)
517 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
518 			      __func__, sizeof(*res), 8);
519 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
520 
521 		res->name = "System RAM";
522 		res->start = start;
523 		/*
524 		 * In memblock, end points to the first byte after the
525 		 * range while in resources, end points to the last byte in
526 		 * the range.
527 		 */
528 		res->end = end - 1;
529 		request_resource(&iomem_resource, res);
530 
531 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
532 			std_res = standard_resources[j];
533 			if (std_res->start < res->start ||
534 			    std_res->start > res->end)
535 				continue;
536 			if (std_res->end > res->end) {
537 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
538 				if (!sub_res)
539 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
540 					      __func__, sizeof(*sub_res), 8);
541 				*sub_res = *std_res;
542 				sub_res->end = res->end;
543 				std_res->start = res->end + 1;
544 				request_resource(res, sub_res);
545 			} else {
546 				request_resource(res, std_res);
547 			}
548 		}
549 	}
550 #ifdef CONFIG_CRASH_DUMP
551 	/*
552 	 * Re-add removed crash kernel memory as reserved memory. This makes
553 	 * sure it will be mapped with the identity mapping and struct pages
554 	 * will be created, so it can be resized later on.
555 	 * However add it later since the crash kernel resource should not be
556 	 * part of the System RAM resource.
557 	 */
558 	if (crashk_res.end) {
559 		memblock_add_node(crashk_res.start, resource_size(&crashk_res),
560 				  0, MEMBLOCK_NONE);
561 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
562 		insert_resource(&iomem_resource, &crashk_res);
563 	}
564 #endif
565 }
566 
setup_memory_end(void)567 static void __init setup_memory_end(void)
568 {
569 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
570 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
571 }
572 
573 #ifdef CONFIG_CRASH_DUMP
574 
575 /*
576  * When kdump is enabled, we have to ensure that no memory from the area
577  * [0 - crashkernel memory size] is set offline - it will be exchanged with
578  * the crashkernel memory region when kdump is triggered. The crashkernel
579  * memory region can never get offlined (pages are unmovable).
580  */
kdump_mem_notifier(struct notifier_block * nb,unsigned long action,void * data)581 static int kdump_mem_notifier(struct notifier_block *nb,
582 			      unsigned long action, void *data)
583 {
584 	struct memory_notify *arg = data;
585 
586 	if (action != MEM_GOING_OFFLINE)
587 		return NOTIFY_OK;
588 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
589 		return NOTIFY_BAD;
590 	return NOTIFY_OK;
591 }
592 
593 static struct notifier_block kdump_mem_nb = {
594 	.notifier_call = kdump_mem_notifier,
595 };
596 
597 #endif
598 
599 /*
600  * Reserve page tables created by decompressor
601  */
reserve_pgtables(void)602 static void __init reserve_pgtables(void)
603 {
604 	unsigned long start, end;
605 	struct reserved_range *range;
606 
607 	for_each_physmem_reserved_type_range(RR_VMEM, range, &start, &end)
608 		memblock_reserve(start, end - start);
609 }
610 
611 /*
612  * Reserve memory for kdump kernel to be loaded with kexec
613  */
reserve_crashkernel(void)614 static void __init reserve_crashkernel(void)
615 {
616 #ifdef CONFIG_CRASH_DUMP
617 	unsigned long long crash_base, crash_size;
618 	phys_addr_t low, high;
619 	int rc;
620 
621 	rc = parse_crashkernel(boot_command_line, ident_map_size,
622 			       &crash_size, &crash_base, NULL, NULL);
623 
624 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
625 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
626 	if (rc || crash_size == 0)
627 		return;
628 
629 	if (memblock.memory.regions[0].size < crash_size) {
630 		pr_info("crashkernel reservation failed: %s\n",
631 			"first memory chunk must be at least crashkernel size");
632 		return;
633 	}
634 
635 	low = crash_base ?: oldmem_data.start;
636 	high = low + crash_size;
637 	if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
638 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
639 		crash_base = low;
640 	} else {
641 		/* Find suitable area in free memory */
642 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
643 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
644 
645 		if (crash_base && crash_base < low) {
646 			pr_info("crashkernel reservation failed: %s\n",
647 				"crash_base too low");
648 			return;
649 		}
650 		low = crash_base ?: low;
651 		crash_base = memblock_phys_alloc_range(crash_size,
652 						       KEXEC_CRASH_MEM_ALIGN,
653 						       low, high);
654 	}
655 
656 	if (!crash_base) {
657 		pr_info("crashkernel reservation failed: %s\n",
658 			"no suitable area found");
659 		return;
660 	}
661 
662 	if (register_memory_notifier(&kdump_mem_nb)) {
663 		memblock_phys_free(crash_base, crash_size);
664 		return;
665 	}
666 
667 	if (!oldmem_data.start && MACHINE_IS_VM)
668 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
669 	crashk_res.start = crash_base;
670 	crashk_res.end = crash_base + crash_size - 1;
671 	memblock_remove(crash_base, crash_size);
672 	pr_info("Reserving %lluMB of memory at %lluMB "
673 		"for crashkernel (System RAM: %luMB)\n",
674 		crash_size >> 20, crash_base >> 20,
675 		(unsigned long)memblock.memory.total_size >> 20);
676 	os_info_crashkernel_add(crash_base, crash_size);
677 #endif
678 }
679 
680 /*
681  * Reserve the initrd from being used by memblock
682  */
reserve_initrd(void)683 static void __init reserve_initrd(void)
684 {
685 	unsigned long addr, size;
686 
687 	if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD) || !get_physmem_reserved(RR_INITRD, &addr, &size))
688 		return;
689 	initrd_start = (unsigned long)__va(addr);
690 	initrd_end = initrd_start + size;
691 	memblock_reserve(addr, size);
692 }
693 
694 /*
695  * Reserve the memory area used to pass the certificate lists
696  */
reserve_certificate_list(void)697 static void __init reserve_certificate_list(void)
698 {
699 	if (ipl_cert_list_addr)
700 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
701 }
702 
reserve_physmem_info(void)703 static void __init reserve_physmem_info(void)
704 {
705 	unsigned long addr, size;
706 
707 	if (get_physmem_reserved(RR_MEM_DETECT_EXTENDED, &addr, &size))
708 		memblock_reserve(addr, size);
709 }
710 
free_physmem_info(void)711 static void __init free_physmem_info(void)
712 {
713 	unsigned long addr, size;
714 
715 	if (get_physmem_reserved(RR_MEM_DETECT_EXTENDED, &addr, &size))
716 		memblock_phys_free(addr, size);
717 }
718 
memblock_add_physmem_info(void)719 static void __init memblock_add_physmem_info(void)
720 {
721 	unsigned long start, end;
722 	int i;
723 
724 	pr_debug("physmem info source: %s (%hhd)\n",
725 		 get_physmem_info_source(), physmem_info.info_source);
726 	/* keep memblock lists close to the kernel */
727 	memblock_set_bottom_up(true);
728 	for_each_physmem_usable_range(i, &start, &end)
729 		memblock_add(start, end - start);
730 	for_each_physmem_online_range(i, &start, &end)
731 		memblock_physmem_add(start, end - start);
732 	memblock_set_bottom_up(false);
733 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
734 }
735 
736 /*
737  * Reserve memory used for lowcore.
738  */
reserve_lowcore(void)739 static void __init reserve_lowcore(void)
740 {
741 	void *lowcore_start = get_lowcore();
742 	void *lowcore_end = lowcore_start + sizeof(struct lowcore);
743 	void *start, *end;
744 
745 	if ((void *)__identity_base < lowcore_end) {
746 		start = max(lowcore_start, (void *)__identity_base);
747 		end = min(lowcore_end, (void *)(__identity_base + ident_map_size));
748 		memblock_reserve(__pa(start), __pa(end));
749 	}
750 }
751 
752 /*
753  * Reserve memory used for absolute lowcore/command line/kernel image.
754  */
reserve_kernel(void)755 static void __init reserve_kernel(void)
756 {
757 	memblock_reserve(0, STARTUP_NORMAL_OFFSET);
758 	memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
759 	memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
760 	memblock_reserve(physmem_info.reserved[RR_AMODE31].start, __eamode31 - __samode31);
761 	memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
762 	memblock_reserve(__pa(_stext), _end - _stext);
763 }
764 
setup_memory(void)765 static void __init setup_memory(void)
766 {
767 	phys_addr_t start, end;
768 	u64 i;
769 
770 	/*
771 	 * Init storage key for present memory
772 	 */
773 	for_each_mem_range(i, &start, &end)
774 		storage_key_init_range(start, end);
775 
776 	psw_set_key(PAGE_DEFAULT_KEY);
777 }
778 
relocate_amode31_section(void)779 static void __init relocate_amode31_section(void)
780 {
781 	unsigned long amode31_size = __eamode31 - __samode31;
782 	long amode31_offset, *ptr;
783 
784 	amode31_offset = AMODE31_START - (unsigned long)__samode31;
785 	pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
786 
787 	/* Move original AMODE31 section to the new one */
788 	memmove((void *)physmem_info.reserved[RR_AMODE31].start, __samode31, amode31_size);
789 	/* Zero out the old AMODE31 section to catch invalid accesses within it */
790 	memset(__samode31, 0, amode31_size);
791 
792 	/* Update all AMODE31 region references */
793 	for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
794 		*ptr += amode31_offset;
795 }
796 
797 /* This must be called after AMODE31 relocation */
setup_cr(void)798 static void __init setup_cr(void)
799 {
800 	union ctlreg2 cr2;
801 	union ctlreg5 cr5;
802 	union ctlreg15 cr15;
803 
804 	__ctl_duct[1] = (unsigned long)__ctl_aste;
805 	__ctl_duct[2] = (unsigned long)__ctl_aste;
806 	__ctl_duct[4] = (unsigned long)__ctl_duald;
807 
808 	/* Update control registers CR2, CR5 and CR15 */
809 	local_ctl_store(2, &cr2.reg);
810 	local_ctl_store(5, &cr5.reg);
811 	local_ctl_store(15, &cr15.reg);
812 	cr2.ducto = (unsigned long)__ctl_duct >> 6;
813 	cr5.pasteo = (unsigned long)__ctl_duct >> 6;
814 	cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
815 	system_ctl_load(2, &cr2.reg);
816 	system_ctl_load(5, &cr5.reg);
817 	system_ctl_load(15, &cr15.reg);
818 }
819 
820 /*
821  * Add system information as device randomness
822  */
setup_randomness(void)823 static void __init setup_randomness(void)
824 {
825 	struct sysinfo_3_2_2 *vmms;
826 
827 	vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
828 	if (!vmms)
829 		panic("Failed to allocate memory for sysinfo structure\n");
830 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
831 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
832 	memblock_free(vmms, PAGE_SIZE);
833 
834 	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
835 		static_branch_enable(&s390_arch_random_available);
836 }
837 
838 /*
839  * Issue diagnose 318 to set the control program name and
840  * version codes.
841  */
setup_control_program_code(void)842 static void __init setup_control_program_code(void)
843 {
844 	union diag318_info diag318_info = {
845 		.cpnc = CPNC_LINUX,
846 		.cpvc = 0,
847 	};
848 
849 	if (!sclp.has_diag318)
850 		return;
851 
852 	diag_stat_inc(DIAG_STAT_X318);
853 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
854 }
855 
856 /*
857  * Print the component list from the IPL report
858  */
log_component_list(void)859 static void __init log_component_list(void)
860 {
861 	struct ipl_rb_component_entry *ptr, *end;
862 	char *str;
863 
864 	if (!early_ipl_comp_list_addr)
865 		return;
866 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
867 		pr_info("Linux is running with Secure-IPL enabled\n");
868 	else
869 		pr_info("Linux is running with Secure-IPL disabled\n");
870 	ptr = __va(early_ipl_comp_list_addr);
871 	end = (void *) ptr + early_ipl_comp_list_size;
872 	pr_info("The IPL report contains the following components:\n");
873 	while (ptr < end) {
874 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
875 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
876 				str = "signed, verified";
877 			else
878 				str = "signed, verification failed";
879 		} else {
880 			str = "not signed";
881 		}
882 		pr_info("%016llx - %016llx (%s)\n",
883 			ptr->addr, ptr->addr + ptr->len, str);
884 		ptr++;
885 	}
886 }
887 
888 /*
889  * Setup function called from init/main.c just after the banner
890  * was printed.
891  */
892 
setup_arch(char ** cmdline_p)893 void __init setup_arch(char **cmdline_p)
894 {
895         /*
896          * print what head.S has found out about the machine
897          */
898 	if (MACHINE_IS_VM)
899 		pr_info("Linux is running as a z/VM "
900 			"guest operating system in 64-bit mode\n");
901 	else if (MACHINE_IS_KVM)
902 		pr_info("Linux is running under KVM in 64-bit mode\n");
903 	else if (MACHINE_IS_LPAR)
904 		pr_info("Linux is running natively in 64-bit mode\n");
905 	else
906 		pr_info("Linux is running as a guest in 64-bit mode\n");
907 
908 	if (have_relocated_lowcore())
909 		pr_info("Lowcore relocated to 0x%px\n", get_lowcore());
910 
911 	log_component_list();
912 
913 	/* Have one command line that is parsed and saved in /proc/cmdline */
914 	/* boot_command_line has been already set up in early.c */
915 	*cmdline_p = boot_command_line;
916 
917         ROOT_DEV = Root_RAM0;
918 
919 	setup_initial_init_mm(_text, _etext, _edata, _end);
920 
921 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
922 		nospec_auto_detect();
923 
924 	jump_label_init();
925 	parse_early_param();
926 #ifdef CONFIG_CRASH_DUMP
927 	/* Deactivate elfcorehdr= kernel parameter */
928 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
929 #endif
930 
931 	os_info_init();
932 	setup_ipl();
933 	setup_control_program_code();
934 
935 	/* Do some memory reservations *before* memory is added to memblock */
936 	reserve_pgtables();
937 	reserve_lowcore();
938 	reserve_kernel();
939 	reserve_initrd();
940 	reserve_certificate_list();
941 	reserve_physmem_info();
942 	memblock_set_current_limit(ident_map_size);
943 	memblock_allow_resize();
944 
945 	/* Get information about *all* installed memory */
946 	memblock_add_physmem_info();
947 
948 	free_physmem_info();
949 	setup_memory_end();
950 	memblock_dump_all();
951 	setup_memory();
952 
953 	relocate_amode31_section();
954 	setup_cr();
955 	setup_uv();
956 	dma_contiguous_reserve(ident_map_size);
957 	vmcp_cma_reserve();
958 	if (MACHINE_HAS_EDAT2)
959 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
960 
961 	reserve_crashkernel();
962 #ifdef CONFIG_CRASH_DUMP
963 	/*
964 	 * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
965 	 * Therefore CPU and device initialization should be done afterwards.
966 	 */
967 	smp_save_dump_secondary_cpus();
968 #endif
969 
970 	setup_resources();
971 	setup_lowcore();
972 	smp_fill_possible_mask();
973 	cpu_detect_mhz_feature();
974         cpu_init();
975 	numa_setup();
976 	smp_detect_cpus();
977 	topology_init_early();
978 
979 	if (test_facility(193))
980 		static_branch_enable(&cpu_has_bear);
981 
982 	/*
983 	 * Create kernel page tables.
984 	 */
985         paging_init();
986 
987 	/*
988 	 * After paging_init created the kernel page table, the new PSWs
989 	 * in lowcore can now run with DAT enabled.
990 	 */
991 #ifdef CONFIG_CRASH_DUMP
992 	smp_save_dump_ipl_cpu();
993 #endif
994 
995         /* Setup default console */
996 	conmode_default();
997 	set_preferred_console();
998 
999 	apply_alternative_instructions();
1000 	if (IS_ENABLED(CONFIG_EXPOLINE))
1001 		nospec_init_branches();
1002 
1003 	/* Setup zfcp/nvme dump support */
1004 	setup_zfcpdump();
1005 
1006 	/* Add system specific data to the random pool */
1007 	setup_randomness();
1008 }
1009