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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/boot_data.h>
56 #include <asm/ipl.h>
57 #include <asm/facility.h>
58 #include <asm/smp.h>
59 #include <asm/mmu_context.h>
60 #include <asm/cpcmd.h>
61 #include <asm/lowcore.h>
62 #include <asm/nmi.h>
63 #include <asm/irq.h>
64 #include <asm/page.h>
65 #include <asm/ptrace.h>
66 #include <asm/sections.h>
67 #include <asm/ebcdic.h>
68 #include <asm/diag.h>
69 #include <asm/os_info.h>
70 #include <asm/sclp.h>
71 #include <asm/stacktrace.h>
72 #include <asm/sysinfo.h>
73 #include <asm/numa.h>
74 #include <asm/alternative.h>
75 #include <asm/nospec-branch.h>
76 #include <asm/mem_detect.h>
77 #include <asm/uv.h>
78 #include <asm/asm-offsets.h>
79 #include "entry.h"
80 
81 /*
82  * Machine setup..
83  */
84 unsigned int console_mode = 0;
85 EXPORT_SYMBOL(console_mode);
86 
87 unsigned int console_devno = -1;
88 EXPORT_SYMBOL(console_devno);
89 
90 unsigned int console_irq = -1;
91 EXPORT_SYMBOL(console_irq);
92 
93 /*
94  * Some code and data needs to stay below 2 GB, even when the kernel would be
95  * relocated above 2 GB, because it has to use 31 bit addresses.
96  * Such code and data is part of the .amode31 section.
97  */
98 unsigned long __amode31_ref __samode31 = (unsigned long)&_samode31;
99 unsigned long __amode31_ref __eamode31 = (unsigned long)&_eamode31;
100 unsigned long __amode31_ref __stext_amode31 = (unsigned long)&_stext_amode31;
101 unsigned long __amode31_ref __etext_amode31 = (unsigned long)&_etext_amode31;
102 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
103 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
104 
105 /*
106  * Control registers CR2, CR5 and CR15 are initialized with addresses
107  * of tables that must be placed below 2G which is handled by the AMODE31
108  * sections.
109  * Because the AMODE31 sections are relocated below 2G at startup,
110  * the content of control registers CR2, CR5 and CR15 must be updated
111  * with new addresses after the relocation. The initial initialization of
112  * control registers occurs in head64.S and then gets updated again after AMODE31
113  * relocation. We must access the relevant AMODE31 tables indirectly via
114  * pointers placed in the .amode31.refs linker section. Those pointers get
115  * updated automatically during AMODE31 relocation and always contain a valid
116  * address within AMODE31 sections.
117  */
118 
119 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
120 
121 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
122 	[1] = 0xffffffffffffffff
123 };
124 
125 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
126 	0x80000000, 0, 0, 0,
127 	0x80000000, 0, 0, 0,
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 };
135 
136 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
137 	0, 0, 0x89000000, 0,
138 	0, 0, 0x8a000000, 0
139 };
140 
141 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
142 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
143 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
144 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
145 
146 int __bootdata(noexec_disabled);
147 unsigned long __bootdata(ident_map_size);
148 struct mem_detect_info __bootdata(mem_detect);
149 struct initrd_data __bootdata(initrd_data);
150 
151 unsigned long __bootdata_preserved(__kaslr_offset);
152 unsigned long __bootdata(__amode31_base);
153 unsigned int __bootdata_preserved(zlib_dfltcc_support);
154 EXPORT_SYMBOL(zlib_dfltcc_support);
155 u64 __bootdata_preserved(stfle_fac_list[16]);
156 EXPORT_SYMBOL(stfle_fac_list);
157 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
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 /*
178  * The Write Back bit position in the physaddr is given by the SLPC PCI.
179  * Leaving the mask zero always uses write through which is safe
180  */
181 unsigned long mio_wb_bit_mask __ro_after_init;
182 
183 /*
184  * This is set up by the setup-routine at boot-time
185  * for S390 need to find out, what we have to setup
186  * using address 0x10400 ...
187  */
188 
189 #include <asm/setup.h>
190 
191 /*
192  * condev= and conmode= setup parameter.
193  */
194 
condev_setup(char * str)195 static int __init condev_setup(char *str)
196 {
197 	int vdev;
198 
199 	vdev = simple_strtoul(str, &str, 0);
200 	if (vdev >= 0 && vdev < 65536) {
201 		console_devno = vdev;
202 		console_irq = -1;
203 	}
204 	return 1;
205 }
206 
207 __setup("condev=", condev_setup);
208 
set_preferred_console(void)209 static void __init set_preferred_console(void)
210 {
211 	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
212 		add_preferred_console("ttyS", 0, NULL);
213 	else if (CONSOLE_IS_3270)
214 		add_preferred_console("tty3270", 0, NULL);
215 	else if (CONSOLE_IS_VT220)
216 		add_preferred_console("ttysclp", 0, NULL);
217 	else if (CONSOLE_IS_HVC)
218 		add_preferred_console("hvc", 0, NULL);
219 }
220 
conmode_setup(char * str)221 static int __init conmode_setup(char *str)
222 {
223 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
224 	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
225                 SET_CONSOLE_SCLP;
226 #endif
227 #if defined(CONFIG_TN3215_CONSOLE)
228 	if (!strcmp(str, "3215"))
229 		SET_CONSOLE_3215;
230 #endif
231 #if defined(CONFIG_TN3270_CONSOLE)
232 	if (!strcmp(str, "3270"))
233 		SET_CONSOLE_3270;
234 #endif
235 	set_preferred_console();
236         return 1;
237 }
238 
239 __setup("conmode=", conmode_setup);
240 
conmode_default(void)241 static void __init conmode_default(void)
242 {
243 	char query_buffer[1024];
244 	char *ptr;
245 
246         if (MACHINE_IS_VM) {
247 		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
248 		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
249 		ptr = strstr(query_buffer, "SUBCHANNEL =");
250 		console_irq = simple_strtoul(ptr + 13, NULL, 16);
251 		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
252 		ptr = strstr(query_buffer, "CONMODE");
253 		/*
254 		 * Set the conmode to 3215 so that the device recognition
255 		 * will set the cu_type of the console to 3215. If the
256 		 * conmode is 3270 and we don't set it back then both
257 		 * 3215 and the 3270 driver will try to access the console
258 		 * device (3215 as console and 3270 as normal tty).
259 		 */
260 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
261 		if (ptr == NULL) {
262 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
263 			SET_CONSOLE_SCLP;
264 #endif
265 			return;
266 		}
267 		if (str_has_prefix(ptr + 8, "3270")) {
268 #if defined(CONFIG_TN3270_CONSOLE)
269 			SET_CONSOLE_3270;
270 #elif defined(CONFIG_TN3215_CONSOLE)
271 			SET_CONSOLE_3215;
272 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
273 			SET_CONSOLE_SCLP;
274 #endif
275 		} else if (str_has_prefix(ptr + 8, "3215")) {
276 #if defined(CONFIG_TN3215_CONSOLE)
277 			SET_CONSOLE_3215;
278 #elif defined(CONFIG_TN3270_CONSOLE)
279 			SET_CONSOLE_3270;
280 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
281 			SET_CONSOLE_SCLP;
282 #endif
283 		}
284 	} else if (MACHINE_IS_KVM) {
285 		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
286 			SET_CONSOLE_VT220;
287 		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
288 			SET_CONSOLE_SCLP;
289 		else
290 			SET_CONSOLE_HVC;
291 	} else {
292 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
293 		SET_CONSOLE_SCLP;
294 #endif
295 	}
296 }
297 
298 #ifdef CONFIG_CRASH_DUMP
setup_zfcpdump(void)299 static void __init setup_zfcpdump(void)
300 {
301 	if (!is_ipl_type_dump())
302 		return;
303 	if (oldmem_data.start)
304 		return;
305 	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
306 	console_loglevel = 2;
307 }
308 #else
setup_zfcpdump(void)309 static inline void setup_zfcpdump(void) {}
310 #endif /* CONFIG_CRASH_DUMP */
311 
312  /*
313  * Reboot, halt and power_off stubs. They just call _machine_restart,
314  * _machine_halt or _machine_power_off.
315  */
316 
machine_restart(char * command)317 void machine_restart(char *command)
318 {
319 	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
320 		/*
321 		 * Only unblank the console if we are called in enabled
322 		 * context or a bust_spinlocks cleared the way for us.
323 		 */
324 		console_unblank();
325 	_machine_restart(command);
326 }
327 
machine_halt(void)328 void machine_halt(void)
329 {
330 	if (!in_interrupt() || oops_in_progress)
331 		/*
332 		 * Only unblank the console if we are called in enabled
333 		 * context or a bust_spinlocks cleared the way for us.
334 		 */
335 		console_unblank();
336 	_machine_halt();
337 }
338 
machine_power_off(void)339 void machine_power_off(void)
340 {
341 	if (!in_interrupt() || oops_in_progress)
342 		/*
343 		 * Only unblank the console if we are called in enabled
344 		 * context or a bust_spinlocks cleared the way for us.
345 		 */
346 		console_unblank();
347 	_machine_power_off();
348 }
349 
350 /*
351  * Dummy power off function.
352  */
353 void (*pm_power_off)(void) = machine_power_off;
354 EXPORT_SYMBOL_GPL(pm_power_off);
355 
356 void *restart_stack;
357 
stack_alloc(void)358 unsigned long stack_alloc(void)
359 {
360 #ifdef CONFIG_VMAP_STACK
361 	void *ret;
362 
363 	ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
364 			     NUMA_NO_NODE, __builtin_return_address(0));
365 	kmemleak_not_leak(ret);
366 	return (unsigned long)ret;
367 #else
368 	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
369 #endif
370 }
371 
stack_free(unsigned long stack)372 void stack_free(unsigned long stack)
373 {
374 #ifdef CONFIG_VMAP_STACK
375 	vfree((void *) stack);
376 #else
377 	free_pages(stack, THREAD_SIZE_ORDER);
378 #endif
379 }
380 
arch_early_irq_init(void)381 int __init arch_early_irq_init(void)
382 {
383 	unsigned long stack;
384 
385 	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
386 	if (!stack)
387 		panic("Couldn't allocate async stack");
388 	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
389 	return 0;
390 }
391 
arch_call_rest_init(void)392 void __init arch_call_rest_init(void)
393 {
394 	unsigned long stack;
395 
396 	stack = stack_alloc();
397 	if (!stack)
398 		panic("Couldn't allocate kernel stack");
399 	current->stack = (void *) stack;
400 #ifdef CONFIG_VMAP_STACK
401 	current->stack_vm_area = (void *) stack;
402 #endif
403 	set_task_stack_end_magic(current);
404 	stack += STACK_INIT_OFFSET;
405 	S390_lowcore.kernel_stack = stack;
406 	call_on_stack_noreturn(rest_init, stack);
407 }
408 
setup_lowcore_dat_off(void)409 static void __init setup_lowcore_dat_off(void)
410 {
411 	unsigned long int_psw_mask = PSW_KERNEL_BITS;
412 	unsigned long mcck_stack;
413 	struct lowcore *lc;
414 
415 	if (IS_ENABLED(CONFIG_KASAN))
416 		int_psw_mask |= PSW_MASK_DAT;
417 
418 	/*
419 	 * Setup lowcore for boot cpu
420 	 */
421 	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
422 	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
423 	if (!lc)
424 		panic("%s: Failed to allocate %zu bytes align=%zx\n",
425 		      __func__, sizeof(*lc), sizeof(*lc));
426 
427 	lc->restart_psw.mask = PSW_KERNEL_BITS;
428 	lc->restart_psw.addr = (unsigned long) restart_int_handler;
429 	lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
430 	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
431 	lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
432 	lc->svc_new_psw.addr = (unsigned long) system_call;
433 	lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
434 	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
435 	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
436 	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
437 	lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
438 	lc->io_new_psw.addr = (unsigned long) io_int_handler;
439 	lc->clock_comparator = clock_comparator_max;
440 	lc->nodat_stack = ((unsigned long) &init_thread_union)
441 		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
442 	lc->current_task = (unsigned long)&init_task;
443 	lc->lpp = LPP_MAGIC;
444 	lc->machine_flags = S390_lowcore.machine_flags;
445 	lc->preempt_count = S390_lowcore.preempt_count;
446 	nmi_alloc_boot_cpu(lc);
447 	lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
448 	lc->exit_timer = S390_lowcore.exit_timer;
449 	lc->user_timer = S390_lowcore.user_timer;
450 	lc->system_timer = S390_lowcore.system_timer;
451 	lc->steal_timer = S390_lowcore.steal_timer;
452 	lc->last_update_timer = S390_lowcore.last_update_timer;
453 	lc->last_update_clock = S390_lowcore.last_update_clock;
454 
455 	/*
456 	 * Allocate the global restart stack which is the same for
457 	 * all CPUs in cast *one* of them does a PSW restart.
458 	 */
459 	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
460 	if (!restart_stack)
461 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
462 		      __func__, THREAD_SIZE, THREAD_SIZE);
463 	restart_stack += STACK_INIT_OFFSET;
464 
465 	/*
466 	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
467 	 * restart data to the absolute zero lowcore. This is necessary if
468 	 * PSW restart is done on an offline CPU that has lowcore zero.
469 	 */
470 	lc->restart_stack = (unsigned long) restart_stack;
471 	lc->restart_fn = (unsigned long) do_restart;
472 	lc->restart_data = 0;
473 	lc->restart_source = -1U;
474 
475 	mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
476 	if (!mcck_stack)
477 		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
478 		      __func__, THREAD_SIZE, THREAD_SIZE);
479 	lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
480 
481 	/* Setup absolute zero lowcore */
482 	put_abs_lowcore(restart_stack, lc->restart_stack);
483 	put_abs_lowcore(restart_fn, lc->restart_fn);
484 	put_abs_lowcore(restart_data, lc->restart_data);
485 	put_abs_lowcore(restart_source, lc->restart_source);
486 	put_abs_lowcore(restart_psw, lc->restart_psw);
487 	put_abs_lowcore(mcesad, lc->mcesad);
488 
489 	lc->spinlock_lockval = arch_spin_lockval(0);
490 	lc->spinlock_index = 0;
491 	arch_spin_lock_setup(0);
492 	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
493 	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
494 	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
495 	lc->preempt_count = PREEMPT_DISABLED;
496 
497 	set_prefix((u32)(unsigned long) lc);
498 	lowcore_ptr[0] = lc;
499 }
500 
setup_lowcore_dat_on(void)501 static void __init setup_lowcore_dat_on(void)
502 {
503 	struct lowcore *lc = lowcore_ptr[0];
504 	int cr;
505 
506 	__ctl_clear_bit(0, 28);
507 	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
508 	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
509 	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
510 	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
511 	__ctl_store(S390_lowcore.cregs_save_area, 0, 15);
512 	__ctl_set_bit(0, 28);
513 	put_abs_lowcore(restart_flags, RESTART_FLAG_CTLREGS);
514 	put_abs_lowcore(program_new_psw, lc->program_new_psw);
515 	for (cr = 0; cr < ARRAY_SIZE(lc->cregs_save_area); cr++)
516 		put_abs_lowcore(cregs_save_area[cr], lc->cregs_save_area[cr]);
517 }
518 
519 static struct resource code_resource = {
520 	.name  = "Kernel code",
521 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
522 };
523 
524 static struct resource data_resource = {
525 	.name = "Kernel data",
526 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
527 };
528 
529 static struct resource bss_resource = {
530 	.name = "Kernel bss",
531 	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
532 };
533 
534 static struct resource __initdata *standard_resources[] = {
535 	&code_resource,
536 	&data_resource,
537 	&bss_resource,
538 };
539 
setup_resources(void)540 static void __init setup_resources(void)
541 {
542 	struct resource *res, *std_res, *sub_res;
543 	phys_addr_t start, end;
544 	int j;
545 	u64 i;
546 
547 	code_resource.start = (unsigned long) _text;
548 	code_resource.end = (unsigned long) _etext - 1;
549 	data_resource.start = (unsigned long) _etext;
550 	data_resource.end = (unsigned long) _edata - 1;
551 	bss_resource.start = (unsigned long) __bss_start;
552 	bss_resource.end = (unsigned long) __bss_stop - 1;
553 
554 	for_each_mem_range(i, &start, &end) {
555 		res = memblock_alloc(sizeof(*res), 8);
556 		if (!res)
557 			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
558 			      __func__, sizeof(*res), 8);
559 		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
560 
561 		res->name = "System RAM";
562 		res->start = start;
563 		/*
564 		 * In memblock, end points to the first byte after the
565 		 * range while in resourses, end points to the last byte in
566 		 * the range.
567 		 */
568 		res->end = end - 1;
569 		request_resource(&iomem_resource, res);
570 
571 		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
572 			std_res = standard_resources[j];
573 			if (std_res->start < res->start ||
574 			    std_res->start > res->end)
575 				continue;
576 			if (std_res->end > res->end) {
577 				sub_res = memblock_alloc(sizeof(*sub_res), 8);
578 				if (!sub_res)
579 					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
580 					      __func__, sizeof(*sub_res), 8);
581 				*sub_res = *std_res;
582 				sub_res->end = res->end;
583 				std_res->start = res->end + 1;
584 				request_resource(res, sub_res);
585 			} else {
586 				request_resource(res, std_res);
587 			}
588 		}
589 	}
590 #ifdef CONFIG_CRASH_DUMP
591 	/*
592 	 * Re-add removed crash kernel memory as reserved memory. This makes
593 	 * sure it will be mapped with the identity mapping and struct pages
594 	 * will be created, so it can be resized later on.
595 	 * However add it later since the crash kernel resource should not be
596 	 * part of the System RAM resource.
597 	 */
598 	if (crashk_res.end) {
599 		memblock_add_node(crashk_res.start, resource_size(&crashk_res),
600 				  0, MEMBLOCK_NONE);
601 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
602 		insert_resource(&iomem_resource, &crashk_res);
603 	}
604 #endif
605 }
606 
setup_memory_end(void)607 static void __init setup_memory_end(void)
608 {
609 	memblock_remove(ident_map_size, ULONG_MAX);
610 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
611 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
612 }
613 
614 #ifdef CONFIG_CRASH_DUMP
615 
616 /*
617  * When kdump is enabled, we have to ensure that no memory from the area
618  * [0 - crashkernel memory size] is set offline - it will be exchanged with
619  * the crashkernel memory region when kdump is triggered. The crashkernel
620  * memory region can never get offlined (pages are unmovable).
621  */
kdump_mem_notifier(struct notifier_block * nb,unsigned long action,void * data)622 static int kdump_mem_notifier(struct notifier_block *nb,
623 			      unsigned long action, void *data)
624 {
625 	struct memory_notify *arg = data;
626 
627 	if (action != MEM_GOING_OFFLINE)
628 		return NOTIFY_OK;
629 	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
630 		return NOTIFY_BAD;
631 	return NOTIFY_OK;
632 }
633 
634 static struct notifier_block kdump_mem_nb = {
635 	.notifier_call = kdump_mem_notifier,
636 };
637 
638 #endif
639 
640 /*
641  * Reserve memory for kdump kernel to be loaded with kexec
642  */
reserve_crashkernel(void)643 static void __init reserve_crashkernel(void)
644 {
645 #ifdef CONFIG_CRASH_DUMP
646 	unsigned long long crash_base, crash_size;
647 	phys_addr_t low, high;
648 	int rc;
649 
650 	rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
651 			       &crash_base);
652 
653 	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
654 	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
655 	if (rc || crash_size == 0)
656 		return;
657 
658 	if (memblock.memory.regions[0].size < crash_size) {
659 		pr_info("crashkernel reservation failed: %s\n",
660 			"first memory chunk must be at least crashkernel size");
661 		return;
662 	}
663 
664 	low = crash_base ?: oldmem_data.start;
665 	high = low + crash_size;
666 	if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
667 		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
668 		crash_base = low;
669 	} else {
670 		/* Find suitable area in free memory */
671 		low = max_t(unsigned long, crash_size, sclp.hsa_size);
672 		high = crash_base ? crash_base + crash_size : ULONG_MAX;
673 
674 		if (crash_base && crash_base < low) {
675 			pr_info("crashkernel reservation failed: %s\n",
676 				"crash_base too low");
677 			return;
678 		}
679 		low = crash_base ?: low;
680 		crash_base = memblock_phys_alloc_range(crash_size,
681 						       KEXEC_CRASH_MEM_ALIGN,
682 						       low, high);
683 	}
684 
685 	if (!crash_base) {
686 		pr_info("crashkernel reservation failed: %s\n",
687 			"no suitable area found");
688 		return;
689 	}
690 
691 	if (register_memory_notifier(&kdump_mem_nb)) {
692 		memblock_free(crash_base, crash_size);
693 		return;
694 	}
695 
696 	if (!oldmem_data.start && MACHINE_IS_VM)
697 		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
698 	crashk_res.start = crash_base;
699 	crashk_res.end = crash_base + crash_size - 1;
700 	memblock_remove(crash_base, crash_size);
701 	pr_info("Reserving %lluMB of memory at %lluMB "
702 		"for crashkernel (System RAM: %luMB)\n",
703 		crash_size >> 20, crash_base >> 20,
704 		(unsigned long)memblock.memory.total_size >> 20);
705 	os_info_crashkernel_add(crash_base, crash_size);
706 #endif
707 }
708 
709 /*
710  * Reserve the initrd from being used by memblock
711  */
reserve_initrd(void)712 static void __init reserve_initrd(void)
713 {
714 #ifdef CONFIG_BLK_DEV_INITRD
715 	if (!initrd_data.start || !initrd_data.size)
716 		return;
717 	initrd_start = initrd_data.start;
718 	initrd_end = initrd_start + initrd_data.size;
719 	memblock_reserve(initrd_data.start, initrd_data.size);
720 #endif
721 }
722 
723 /*
724  * Reserve the memory area used to pass the certificate lists
725  */
reserve_certificate_list(void)726 static void __init reserve_certificate_list(void)
727 {
728 	if (ipl_cert_list_addr)
729 		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
730 }
731 
reserve_mem_detect_info(void)732 static void __init reserve_mem_detect_info(void)
733 {
734 	unsigned long start, size;
735 
736 	get_mem_detect_reserved(&start, &size);
737 	if (size)
738 		memblock_reserve(start, size);
739 }
740 
free_mem_detect_info(void)741 static void __init free_mem_detect_info(void)
742 {
743 	unsigned long start, size;
744 
745 	get_mem_detect_reserved(&start, &size);
746 	if (size)
747 		memblock_free(start, size);
748 }
749 
get_mem_info_source(void)750 static const char * __init get_mem_info_source(void)
751 {
752 	switch (mem_detect.info_source) {
753 	case MEM_DETECT_SCLP_STOR_INFO:
754 		return "sclp storage info";
755 	case MEM_DETECT_DIAG260:
756 		return "diag260";
757 	case MEM_DETECT_SCLP_READ_INFO:
758 		return "sclp read info";
759 	case MEM_DETECT_BIN_SEARCH:
760 		return "binary search";
761 	}
762 	return "none";
763 }
764 
memblock_add_mem_detect_info(void)765 static void __init memblock_add_mem_detect_info(void)
766 {
767 	unsigned long start, end;
768 	int i;
769 
770 	pr_debug("physmem info source: %s (%hhd)\n",
771 		 get_mem_info_source(), mem_detect.info_source);
772 	/* keep memblock lists close to the kernel */
773 	memblock_set_bottom_up(true);
774 	for_each_mem_detect_block(i, &start, &end) {
775 		memblock_add(start, end - start);
776 		memblock_physmem_add(start, end - start);
777 	}
778 	memblock_set_bottom_up(false);
779 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
780 	memblock_dump_all();
781 }
782 
783 /*
784  * Check for initrd being in usable memory
785  */
check_initrd(void)786 static void __init check_initrd(void)
787 {
788 #ifdef CONFIG_BLK_DEV_INITRD
789 	if (initrd_data.start && initrd_data.size &&
790 	    !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
791 		pr_err("The initial RAM disk does not fit into the memory\n");
792 		memblock_free(initrd_data.start, initrd_data.size);
793 		initrd_start = initrd_end = 0;
794 	}
795 #endif
796 }
797 
798 /*
799  * Reserve memory used for lowcore/command line/kernel image.
800  */
reserve_kernel(void)801 static void __init reserve_kernel(void)
802 {
803 	memblock_reserve(0, STARTUP_NORMAL_OFFSET);
804 	memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
805 	memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
806 	memblock_reserve(__amode31_base, __eamode31 - __samode31);
807 	memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
808 	memblock_reserve(__pa(_stext), _end - _stext);
809 }
810 
setup_memory(void)811 static void __init setup_memory(void)
812 {
813 	phys_addr_t start, end;
814 	u64 i;
815 
816 	/*
817 	 * Init storage key for present memory
818 	 */
819 	for_each_mem_range(i, &start, &end)
820 		storage_key_init_range(start, end);
821 
822 	psw_set_key(PAGE_DEFAULT_KEY);
823 }
824 
relocate_amode31_section(void)825 static void __init relocate_amode31_section(void)
826 {
827 	unsigned long amode31_size = __eamode31 - __samode31;
828 	long amode31_offset = __amode31_base - __samode31;
829 	long *ptr;
830 
831 	pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
832 
833 	/* Move original AMODE31 section to the new one */
834 	memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
835 	/* Zero out the old AMODE31 section to catch invalid accesses within it */
836 	memset((void *)__samode31, 0, amode31_size);
837 
838 	/* Update all AMODE31 region references */
839 	for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
840 		*ptr += amode31_offset;
841 }
842 
843 /* This must be called after AMODE31 relocation */
setup_cr(void)844 static void __init setup_cr(void)
845 {
846 	union ctlreg2 cr2;
847 	union ctlreg5 cr5;
848 	union ctlreg15 cr15;
849 
850 	__ctl_duct[1] = (unsigned long)__ctl_aste;
851 	__ctl_duct[2] = (unsigned long)__ctl_aste;
852 	__ctl_duct[4] = (unsigned long)__ctl_duald;
853 
854 	/* Update control registers CR2, CR5 and CR15 */
855 	__ctl_store(cr2.val, 2, 2);
856 	__ctl_store(cr5.val, 5, 5);
857 	__ctl_store(cr15.val, 15, 15);
858 	cr2.ducto = (unsigned long)__ctl_duct >> 6;
859 	cr5.pasteo = (unsigned long)__ctl_duct >> 6;
860 	cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
861 	__ctl_load(cr2.val, 2, 2);
862 	__ctl_load(cr5.val, 5, 5);
863 	__ctl_load(cr15.val, 15, 15);
864 }
865 
866 /*
867  * Add system information as device randomness
868  */
setup_randomness(void)869 static void __init setup_randomness(void)
870 {
871 	struct sysinfo_3_2_2 *vmms;
872 
873 	vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
874 							    PAGE_SIZE);
875 	if (!vmms)
876 		panic("Failed to allocate memory for sysinfo structure\n");
877 
878 	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
879 		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
880 	memblock_free((unsigned long) vmms, PAGE_SIZE);
881 
882 #ifdef CONFIG_ARCH_RANDOM
883 	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
884 		static_branch_enable(&s390_arch_random_available);
885 #endif
886 }
887 
888 /*
889  * Find the correct size for the task_struct. This depends on
890  * the size of the struct fpu at the end of the thread_struct
891  * which is embedded in the task_struct.
892  */
setup_task_size(void)893 static void __init setup_task_size(void)
894 {
895 	int task_size = sizeof(struct task_struct);
896 
897 	if (!MACHINE_HAS_VX) {
898 		task_size -= sizeof(__vector128) * __NUM_VXRS;
899 		task_size += sizeof(freg_t) * __NUM_FPRS;
900 	}
901 	arch_task_struct_size = task_size;
902 }
903 
904 /*
905  * Issue diagnose 318 to set the control program name and
906  * version codes.
907  */
setup_control_program_code(void)908 static void __init setup_control_program_code(void)
909 {
910 	union diag318_info diag318_info = {
911 		.cpnc = CPNC_LINUX,
912 		.cpvc = 0,
913 	};
914 
915 	if (!sclp.has_diag318)
916 		return;
917 
918 	diag_stat_inc(DIAG_STAT_X318);
919 	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
920 }
921 
922 /*
923  * Print the component list from the IPL report
924  */
log_component_list(void)925 static void __init log_component_list(void)
926 {
927 	struct ipl_rb_component_entry *ptr, *end;
928 	char *str;
929 
930 	if (!early_ipl_comp_list_addr)
931 		return;
932 	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
933 		pr_info("Linux is running with Secure-IPL enabled\n");
934 	else
935 		pr_info("Linux is running with Secure-IPL disabled\n");
936 	ptr = (void *) early_ipl_comp_list_addr;
937 	end = (void *) ptr + early_ipl_comp_list_size;
938 	pr_info("The IPL report contains the following components:\n");
939 	while (ptr < end) {
940 		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
941 			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
942 				str = "signed, verified";
943 			else
944 				str = "signed, verification failed";
945 		} else {
946 			str = "not signed";
947 		}
948 		pr_info("%016llx - %016llx (%s)\n",
949 			ptr->addr, ptr->addr + ptr->len, str);
950 		ptr++;
951 	}
952 }
953 
954 /*
955  * Setup function called from init/main.c just after the banner
956  * was printed.
957  */
958 
setup_arch(char ** cmdline_p)959 void __init setup_arch(char **cmdline_p)
960 {
961         /*
962          * print what head.S has found out about the machine
963          */
964 	if (MACHINE_IS_VM)
965 		pr_info("Linux is running as a z/VM "
966 			"guest operating system in 64-bit mode\n");
967 	else if (MACHINE_IS_KVM)
968 		pr_info("Linux is running under KVM in 64-bit mode\n");
969 	else if (MACHINE_IS_LPAR)
970 		pr_info("Linux is running natively in 64-bit mode\n");
971 	else
972 		pr_info("Linux is running as a guest in 64-bit mode\n");
973 
974 	log_component_list();
975 
976 	/* Have one command line that is parsed and saved in /proc/cmdline */
977 	/* boot_command_line has been already set up in early.c */
978 	*cmdline_p = boot_command_line;
979 
980         ROOT_DEV = Root_RAM0;
981 
982 	setup_initial_init_mm(_text, _etext, _edata, _end);
983 
984 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
985 		nospec_auto_detect();
986 
987 	jump_label_init();
988 	parse_early_param();
989 #ifdef CONFIG_CRASH_DUMP
990 	/* Deactivate elfcorehdr= kernel parameter */
991 	elfcorehdr_addr = ELFCORE_ADDR_MAX;
992 #endif
993 
994 	os_info_init();
995 	setup_ipl();
996 	setup_task_size();
997 	setup_control_program_code();
998 
999 	/* Do some memory reservations *before* memory is added to memblock */
1000 	reserve_kernel();
1001 	reserve_initrd();
1002 	reserve_certificate_list();
1003 	reserve_mem_detect_info();
1004 	memblock_set_current_limit(ident_map_size);
1005 	memblock_allow_resize();
1006 
1007 	/* Get information about *all* installed memory */
1008 	memblock_add_mem_detect_info();
1009 
1010 	free_mem_detect_info();
1011 
1012 	relocate_amode31_section();
1013 	setup_cr();
1014 
1015 	setup_uv();
1016 	setup_memory_end();
1017 	setup_memory();
1018 	dma_contiguous_reserve(ident_map_size);
1019 	vmcp_cma_reserve();
1020 	if (MACHINE_HAS_EDAT2)
1021 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1022 
1023 	check_initrd();
1024 	reserve_crashkernel();
1025 #ifdef CONFIG_CRASH_DUMP
1026 	/*
1027 	 * Be aware that smp_save_dump_cpus() triggers a system reset.
1028 	 * Therefore CPU and device initialization should be done afterwards.
1029 	 */
1030 	smp_save_dump_cpus();
1031 #endif
1032 
1033 	setup_resources();
1034 	setup_lowcore_dat_off();
1035 	smp_fill_possible_mask();
1036 	cpu_detect_mhz_feature();
1037         cpu_init();
1038 	numa_setup();
1039 	smp_detect_cpus();
1040 	topology_init_early();
1041 
1042 	/*
1043 	 * Create kernel page tables and switch to virtual addressing.
1044 	 */
1045         paging_init();
1046 
1047 	/*
1048 	 * After paging_init created the kernel page table, the new PSWs
1049 	 * in lowcore can now run with DAT enabled.
1050 	 */
1051 	setup_lowcore_dat_on();
1052 
1053         /* Setup default console */
1054 	conmode_default();
1055 	set_preferred_console();
1056 
1057 	apply_alternative_instructions();
1058 	if (IS_ENABLED(CONFIG_EXPOLINE))
1059 		nospec_init_branches();
1060 
1061 	/* Setup zfcp/nvme dump support */
1062 	setup_zfcpdump();
1063 
1064 	/* Add system specific data to the random pool */
1065 	setup_randomness();
1066 }
1067