xref: /linux/arch/s390/kernel/setup.c (revision e7dec0b7)
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_GPL(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 u64 alt_stfle_fac_list[16];
159 struct oldmem_data __bootdata_preserved(oldmem_data);
160 
161 unsigned long VMALLOC_START;
162 EXPORT_SYMBOL(VMALLOC_START);
163 
164 unsigned long VMALLOC_END;
165 EXPORT_SYMBOL(VMALLOC_END);
166 
167 struct page *vmemmap;
168 EXPORT_SYMBOL(vmemmap);
169 unsigned long vmemmap_size;
170 
171 unsigned long MODULES_VADDR;
172 unsigned long MODULES_END;
173 
174 /* An array with a pointer to the lowcore of every CPU. */
175 struct lowcore *lowcore_ptr[NR_CPUS];
176 EXPORT_SYMBOL(lowcore_ptr);
177 
178 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
179 
180 /*
181  * The Write Back bit position in the physaddr is given by the SLPC PCI.
182  * Leaving the mask zero always uses write through which is safe
183  */
184 unsigned long mio_wb_bit_mask __ro_after_init;
185 
186 /*
187  * This is set up by the setup-routine at boot-time
188  * for S390 need to find out, what we have to setup
189  * using address 0x10400 ...
190  */
191 
192 #include <asm/setup.h>
193 
194 /*
195  * condev= and conmode= setup parameter.
196  */
197 
condev_setup(char * str)198 static int __init condev_setup(char *str)
199 {
200 	int vdev;
201 
202 	vdev = simple_strtoul(str, &str, 0);
203 	if (vdev >= 0 && vdev < 65536) {
204 		console_devno = vdev;
205 		console_irq = -1;
206 	}
207 	return 1;
208 }
209 
210 __setup("condev=", condev_setup);
211 
set_preferred_console(void)212 static void __init set_preferred_console(void)
213 {
214 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
215 		add_preferred_console("ttyS", 0, NULL);
216 	else if (CONSOLE_IS_3270)
217 		add_preferred_console("tty3270", 0, NULL);
218 	else if (CONSOLE_IS_VT220)
219 		add_preferred_console("ttysclp", 0, NULL);
220 	else if (CONSOLE_IS_HVC)
221 		add_preferred_console("hvc", 0, NULL);
222 }
223 
conmode_setup(char * str)224 static int __init conmode_setup(char *str)
225 {
226 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
227 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
228                 SET_CONSOLE_SCLP;
229 #endif
230 #if defined(CONFIG_TN3215_CONSOLE)
231 	if (!strcmp(str, "3215"))
232 		SET_CONSOLE_3215;
233 #endif
234 #if defined(CONFIG_TN3270_CONSOLE)
235 	if (!strcmp(str, "3270"))
236 		SET_CONSOLE_3270;
237 #endif
238 	set_preferred_console();
239         return 1;
240 }
241 
242 __setup("conmode=", conmode_setup);
243 
conmode_default(void)244 static void __init conmode_default(void)
245 {
246 	char query_buffer[1024];
247 	char *ptr;
248 
249         if (MACHINE_IS_VM) {
250 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
251 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
252 		ptr = strstr(query_buffer, "SUBCHANNEL =");
253 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
254 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
255 		ptr = strstr(query_buffer, "CONMODE");
256 		/*
257 		 * Set the conmode to 3215 so that the device recognition
258 		 * will set the cu_type of the console to 3215. If the
259 		 * conmode is 3270 and we don't set it back then both
260 		 * 3215 and the 3270 driver will try to access the console
261 		 * device (3215 as console and 3270 as normal tty).
262 		 */
263 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
264 		if (ptr == NULL) {
265 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
266 			SET_CONSOLE_SCLP;
267 #endif
268 			return;
269 		}
270 		if (str_has_prefix(ptr + 8, "3270")) {
271 #if defined(CONFIG_TN3270_CONSOLE)
272 			SET_CONSOLE_3270;
273 #elif defined(CONFIG_TN3215_CONSOLE)
274 			SET_CONSOLE_3215;
275 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
276 			SET_CONSOLE_SCLP;
277 #endif
278 		} else if (str_has_prefix(ptr + 8, "3215")) {
279 #if defined(CONFIG_TN3215_CONSOLE)
280 			SET_CONSOLE_3215;
281 #elif defined(CONFIG_TN3270_CONSOLE)
282 			SET_CONSOLE_3270;
283 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
284 			SET_CONSOLE_SCLP;
285 #endif
286 		}
287 	} else if (MACHINE_IS_KVM) {
288 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
289 			SET_CONSOLE_VT220;
290 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
291 			SET_CONSOLE_SCLP;
292 		else
293 			SET_CONSOLE_HVC;
294 	} else {
295 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
296 		SET_CONSOLE_SCLP;
297 #endif
298 	}
299 }
300 
301 #ifdef CONFIG_CRASH_DUMP
setup_zfcpdump(void)302 static void __init setup_zfcpdump(void)
303 {
304 	if (!is_ipl_type_dump())
305 		return;
306 	if (oldmem_data.start)
307 		return;
308 	strlcat(boot_command_line, " cio_ignore=all,!ipldev,!condev", COMMAND_LINE_SIZE);
309 	console_loglevel = 2;
310 }
311 #else
setup_zfcpdump(void)312 static inline void setup_zfcpdump(void) {}
313 #endif /* CONFIG_CRASH_DUMP */
314 
315  /*
316  * Reboot, halt and power_off stubs. They just call _machine_restart,
317  * _machine_halt or _machine_power_off.
318  */
319 
machine_restart(char * command)320 void machine_restart(char *command)
321 {
322 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
323 		/*
324 		 * Only unblank the console if we are called in enabled
325 		 * context or a bust_spinlocks cleared the way for us.
326 		 */
327 		console_unblank();
328 	_machine_restart(command);
329 }
330 
machine_halt(void)331 void machine_halt(void)
332 {
333 	if (!in_interrupt() || oops_in_progress)
334 		/*
335 		 * Only unblank the console if we are called in enabled
336 		 * context or a bust_spinlocks cleared the way for us.
337 		 */
338 		console_unblank();
339 	_machine_halt();
340 }
341 
machine_power_off(void)342 void machine_power_off(void)
343 {
344 	if (!in_interrupt() || oops_in_progress)
345 		/*
346 		 * Only unblank the console if we are called in enabled
347 		 * context or a bust_spinlocks cleared the way for us.
348 		 */
349 		console_unblank();
350 	_machine_power_off();
351 }
352 
353 /*
354  * Dummy power off function.
355  */
356 void (*pm_power_off)(void) = machine_power_off;
357 EXPORT_SYMBOL_GPL(pm_power_off);
358 
359 void *restart_stack;
360 
stack_alloc(void)361 unsigned long stack_alloc(void)
362 {
363 #ifdef CONFIG_VMAP_STACK
364 	void *ret;
365 
366 	ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
367 			     NUMA_NO_NODE, __builtin_return_address(0));
368 	kmemleak_not_leak(ret);
369 	return (unsigned long)ret;
370 #else
371 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
372 #endif
373 }
374 
stack_free(unsigned long stack)375 void stack_free(unsigned long stack)
376 {
377 #ifdef CONFIG_VMAP_STACK
378 	vfree((void *) stack);
379 #else
380 	free_pages(stack, THREAD_SIZE_ORDER);
381 #endif
382 }
383 
stack_alloc_early(void)384 static unsigned long __init stack_alloc_early(void)
385 {
386 	unsigned long stack;
387 
388 	stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
389 	if (!stack) {
390 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
391 		      __func__, THREAD_SIZE, THREAD_SIZE);
392 	}
393 	return stack;
394 }
395 
setup_lowcore(void)396 static void __init setup_lowcore(void)
397 {
398 	struct lowcore *lc, *abs_lc;
399 
400 	/*
401 	 * Setup lowcore for boot cpu
402 	 */
403 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
404 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
405 	if (!lc)
406 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
407 		      __func__, sizeof(*lc), sizeof(*lc));
408 
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 = S390_lowcore.machine_flags;
425 	lc->preempt_count = S390_lowcore.preempt_count;
426 	nmi_alloc_mcesa_early(&lc->mcesad);
427 	lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
428 	lc->exit_timer = S390_lowcore.exit_timer;
429 	lc->user_timer = S390_lowcore.user_timer;
430 	lc->system_timer = S390_lowcore.system_timer;
431 	lc->steal_timer = S390_lowcore.steal_timer;
432 	lc->last_update_timer = S390_lowcore.last_update_timer;
433 	lc->last_update_clock = S390_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 = S390_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 = S390_lowcore.kernel_asce;
459 	lc->user_asce = S390_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/command line/kernel image.
738  */
reserve_kernel(void)739 static void __init reserve_kernel(void)
740 {
741 	memblock_reserve(0, STARTUP_NORMAL_OFFSET);
742 	memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
743 	memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
744 	memblock_reserve(physmem_info.reserved[RR_AMODE31].start, __eamode31 - __samode31);
745 	memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
746 	memblock_reserve(__pa(_stext), _end - _stext);
747 }
748 
setup_memory(void)749 static void __init setup_memory(void)
750 {
751 	phys_addr_t start, end;
752 	u64 i;
753 
754 	/*
755 	 * Init storage key for present memory
756 	 */
757 	for_each_mem_range(i, &start, &end)
758 		storage_key_init_range(start, end);
759 
760 	psw_set_key(PAGE_DEFAULT_KEY);
761 }
762 
relocate_amode31_section(void)763 static void __init relocate_amode31_section(void)
764 {
765 	unsigned long amode31_size = __eamode31 - __samode31;
766 	long amode31_offset, *ptr;
767 
768 	amode31_offset = AMODE31_START - (unsigned long)__samode31;
769 	pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
770 
771 	/* Move original AMODE31 section to the new one */
772 	memmove((void *)physmem_info.reserved[RR_AMODE31].start, __samode31, amode31_size);
773 	/* Zero out the old AMODE31 section to catch invalid accesses within it */
774 	memset(__samode31, 0, amode31_size);
775 
776 	/* Update all AMODE31 region references */
777 	for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
778 		*ptr += amode31_offset;
779 }
780 
781 /* This must be called after AMODE31 relocation */
setup_cr(void)782 static void __init setup_cr(void)
783 {
784 	union ctlreg2 cr2;
785 	union ctlreg5 cr5;
786 	union ctlreg15 cr15;
787 
788 	__ctl_duct[1] = (unsigned long)__ctl_aste;
789 	__ctl_duct[2] = (unsigned long)__ctl_aste;
790 	__ctl_duct[4] = (unsigned long)__ctl_duald;
791 
792 	/* Update control registers CR2, CR5 and CR15 */
793 	local_ctl_store(2, &cr2.reg);
794 	local_ctl_store(5, &cr5.reg);
795 	local_ctl_store(15, &cr15.reg);
796 	cr2.ducto = (unsigned long)__ctl_duct >> 6;
797 	cr5.pasteo = (unsigned long)__ctl_duct >> 6;
798 	cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
799 	system_ctl_load(2, &cr2.reg);
800 	system_ctl_load(5, &cr5.reg);
801 	system_ctl_load(15, &cr15.reg);
802 }
803 
804 /*
805  * Add system information as device randomness
806  */
setup_randomness(void)807 static void __init setup_randomness(void)
808 {
809 	struct sysinfo_3_2_2 *vmms;
810 
811 	vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
812 	if (!vmms)
813 		panic("Failed to allocate memory for sysinfo structure\n");
814 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
815 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
816 	memblock_free(vmms, PAGE_SIZE);
817 
818 	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
819 		static_branch_enable(&s390_arch_random_available);
820 }
821 
822 /*
823  * Issue diagnose 318 to set the control program name and
824  * version codes.
825  */
setup_control_program_code(void)826 static void __init setup_control_program_code(void)
827 {
828 	union diag318_info diag318_info = {
829 		.cpnc = CPNC_LINUX,
830 		.cpvc = 0,
831 	};
832 
833 	if (!sclp.has_diag318)
834 		return;
835 
836 	diag_stat_inc(DIAG_STAT_X318);
837 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
838 }
839 
840 /*
841  * Print the component list from the IPL report
842  */
log_component_list(void)843 static void __init log_component_list(void)
844 {
845 	struct ipl_rb_component_entry *ptr, *end;
846 	char *str;
847 
848 	if (!early_ipl_comp_list_addr)
849 		return;
850 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
851 		pr_info("Linux is running with Secure-IPL enabled\n");
852 	else
853 		pr_info("Linux is running with Secure-IPL disabled\n");
854 	ptr = __va(early_ipl_comp_list_addr);
855 	end = (void *) ptr + early_ipl_comp_list_size;
856 	pr_info("The IPL report contains the following components:\n");
857 	while (ptr < end) {
858 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
859 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
860 				str = "signed, verified";
861 			else
862 				str = "signed, verification failed";
863 		} else {
864 			str = "not signed";
865 		}
866 		pr_info("%016llx - %016llx (%s)\n",
867 			ptr->addr, ptr->addr + ptr->len, str);
868 		ptr++;
869 	}
870 }
871 
872 /*
873  * Setup function called from init/main.c just after the banner
874  * was printed.
875  */
876 
setup_arch(char ** cmdline_p)877 void __init setup_arch(char **cmdline_p)
878 {
879         /*
880          * print what head.S has found out about the machine
881          */
882 	if (MACHINE_IS_VM)
883 		pr_info("Linux is running as a z/VM "
884 			"guest operating system in 64-bit mode\n");
885 	else if (MACHINE_IS_KVM)
886 		pr_info("Linux is running under KVM in 64-bit mode\n");
887 	else if (MACHINE_IS_LPAR)
888 		pr_info("Linux is running natively in 64-bit mode\n");
889 	else
890 		pr_info("Linux is running as a guest in 64-bit mode\n");
891 
892 	log_component_list();
893 
894 	/* Have one command line that is parsed and saved in /proc/cmdline */
895 	/* boot_command_line has been already set up in early.c */
896 	*cmdline_p = boot_command_line;
897 
898         ROOT_DEV = Root_RAM0;
899 
900 	setup_initial_init_mm(_text, _etext, _edata, _end);
901 
902 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
903 		nospec_auto_detect();
904 
905 	jump_label_init();
906 	parse_early_param();
907 #ifdef CONFIG_CRASH_DUMP
908 	/* Deactivate elfcorehdr= kernel parameter */
909 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
910 #endif
911 
912 	os_info_init();
913 	setup_ipl();
914 	setup_control_program_code();
915 
916 	/* Do some memory reservations *before* memory is added to memblock */
917 	reserve_pgtables();
918 	reserve_kernel();
919 	reserve_initrd();
920 	reserve_certificate_list();
921 	reserve_physmem_info();
922 	memblock_set_current_limit(ident_map_size);
923 	memblock_allow_resize();
924 
925 	/* Get information about *all* installed memory */
926 	memblock_add_physmem_info();
927 
928 	free_physmem_info();
929 	setup_memory_end();
930 	memblock_dump_all();
931 	setup_memory();
932 
933 	relocate_amode31_section();
934 	setup_cr();
935 	setup_uv();
936 	dma_contiguous_reserve(ident_map_size);
937 	vmcp_cma_reserve();
938 	if (MACHINE_HAS_EDAT2)
939 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
940 
941 	reserve_crashkernel();
942 #ifdef CONFIG_CRASH_DUMP
943 	/*
944 	 * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
945 	 * Therefore CPU and device initialization should be done afterwards.
946 	 */
947 	smp_save_dump_secondary_cpus();
948 #endif
949 
950 	setup_resources();
951 	setup_lowcore();
952 	smp_fill_possible_mask();
953 	cpu_detect_mhz_feature();
954         cpu_init();
955 	numa_setup();
956 	smp_detect_cpus();
957 	topology_init_early();
958 
959 	if (test_facility(193))
960 		static_branch_enable(&cpu_has_bear);
961 
962 	/*
963 	 * Create kernel page tables.
964 	 */
965         paging_init();
966 
967 	/*
968 	 * After paging_init created the kernel page table, the new PSWs
969 	 * in lowcore can now run with DAT enabled.
970 	 */
971 #ifdef CONFIG_CRASH_DUMP
972 	smp_save_dump_ipl_cpu();
973 #endif
974 
975         /* Setup default console */
976 	conmode_default();
977 	set_preferred_console();
978 
979 	apply_alternative_instructions();
980 	if (IS_ENABLED(CONFIG_EXPOLINE))
981 		nospec_init_branches();
982 
983 	/* Setup zfcp/nvme dump support */
984 	setup_zfcpdump();
985 
986 	/* Add system specific data to the random pool */
987 	setup_randomness();
988 }
989