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 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 strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
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
arch_early_irq_init(void)383 int __init arch_early_irq_init(void)
384 {
385 unsigned long stack;
386
387 stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
388 if (!stack)
389 panic("Couldn't allocate async stack");
390 S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
391 return 0;
392 }
393
arch_call_rest_init(void)394 void __init arch_call_rest_init(void)
395 {
396 unsigned long stack;
397
398 stack = stack_alloc();
399 if (!stack)
400 panic("Couldn't allocate kernel stack");
401 current->stack = (void *) stack;
402 #ifdef CONFIG_VMAP_STACK
403 current->stack_vm_area = (void *) stack;
404 #endif
405 set_task_stack_end_magic(current);
406 stack += STACK_INIT_OFFSET;
407 S390_lowcore.kernel_stack = stack;
408 call_on_stack_noreturn(rest_init, stack);
409 }
410
setup_lowcore_dat_off(void)411 static void __init setup_lowcore_dat_off(void)
412 {
413 unsigned long int_psw_mask = PSW_KERNEL_BITS;
414 unsigned long mcck_stack;
415 struct lowcore *lc;
416
417 if (IS_ENABLED(CONFIG_KASAN))
418 int_psw_mask |= PSW_MASK_DAT;
419
420 /*
421 * Setup lowcore for boot cpu
422 */
423 BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
424 lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
425 if (!lc)
426 panic("%s: Failed to allocate %zu bytes align=%zx\n",
427 __func__, sizeof(*lc), sizeof(*lc));
428
429 lc->restart_psw.mask = PSW_KERNEL_BITS;
430 lc->restart_psw.addr = (unsigned long) restart_int_handler;
431 lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
432 lc->external_new_psw.addr = (unsigned long) ext_int_handler;
433 lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
434 lc->svc_new_psw.addr = (unsigned long) system_call;
435 lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
436 lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
437 lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
438 lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
439 lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
440 lc->io_new_psw.addr = (unsigned long) io_int_handler;
441 lc->clock_comparator = clock_comparator_max;
442 lc->nodat_stack = ((unsigned long) &init_thread_union)
443 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
444 lc->current_task = (unsigned long)&init_task;
445 lc->lpp = LPP_MAGIC;
446 lc->machine_flags = S390_lowcore.machine_flags;
447 lc->preempt_count = S390_lowcore.preempt_count;
448 nmi_alloc_mcesa_early(&lc->mcesad);
449 lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
450 lc->exit_timer = S390_lowcore.exit_timer;
451 lc->user_timer = S390_lowcore.user_timer;
452 lc->system_timer = S390_lowcore.system_timer;
453 lc->steal_timer = S390_lowcore.steal_timer;
454 lc->last_update_timer = S390_lowcore.last_update_timer;
455 lc->last_update_clock = S390_lowcore.last_update_clock;
456
457 /*
458 * Allocate the global restart stack which is the same for
459 * all CPUs in cast *one* of them does a PSW restart.
460 */
461 restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
462 if (!restart_stack)
463 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
464 __func__, THREAD_SIZE, THREAD_SIZE);
465 restart_stack += STACK_INIT_OFFSET;
466
467 /*
468 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
469 * restart data to the absolute zero lowcore. This is necessary if
470 * PSW restart is done on an offline CPU that has lowcore zero.
471 */
472 lc->restart_stack = (unsigned long) restart_stack;
473 lc->restart_fn = (unsigned long) do_restart;
474 lc->restart_data = 0;
475 lc->restart_source = -1U;
476
477 mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
478 if (!mcck_stack)
479 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
480 __func__, THREAD_SIZE, THREAD_SIZE);
481 lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
482
483 /* Setup absolute zero lowcore */
484 put_abs_lowcore(restart_stack, lc->restart_stack);
485 put_abs_lowcore(restart_fn, lc->restart_fn);
486 put_abs_lowcore(restart_data, lc->restart_data);
487 put_abs_lowcore(restart_source, lc->restart_source);
488 put_abs_lowcore(restart_psw, lc->restart_psw);
489 put_abs_lowcore(mcesad, lc->mcesad);
490
491 lc->spinlock_lockval = arch_spin_lockval(0);
492 lc->spinlock_index = 0;
493 arch_spin_lock_setup(0);
494 lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
495 lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
496 lc->preempt_count = PREEMPT_DISABLED;
497
498 set_prefix(__pa(lc));
499 lowcore_ptr[0] = lc;
500 }
501
setup_lowcore_dat_on(void)502 static void __init setup_lowcore_dat_on(void)
503 {
504 struct lowcore *lc = lowcore_ptr[0];
505 int cr;
506
507 __ctl_clear_bit(0, 28);
508 S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
509 S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
510 S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
511 S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
512 __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
513 __ctl_set_bit(0, 28);
514 put_abs_lowcore(restart_flags, RESTART_FLAG_CTLREGS);
515 put_abs_lowcore(program_new_psw, lc->program_new_psw);
516 for (cr = 0; cr < ARRAY_SIZE(lc->cregs_save_area); cr++)
517 put_abs_lowcore(cregs_save_area[cr], lc->cregs_save_area[cr]);
518 }
519
520 static struct resource code_resource = {
521 .name = "Kernel code",
522 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
523 };
524
525 static struct resource data_resource = {
526 .name = "Kernel data",
527 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
528 };
529
530 static struct resource bss_resource = {
531 .name = "Kernel bss",
532 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
533 };
534
535 static struct resource __initdata *standard_resources[] = {
536 &code_resource,
537 &data_resource,
538 &bss_resource,
539 };
540
setup_resources(void)541 static void __init setup_resources(void)
542 {
543 struct resource *res, *std_res, *sub_res;
544 phys_addr_t start, end;
545 int j;
546 u64 i;
547
548 code_resource.start = (unsigned long) _text;
549 code_resource.end = (unsigned long) _etext - 1;
550 data_resource.start = (unsigned long) _etext;
551 data_resource.end = (unsigned long) _edata - 1;
552 bss_resource.start = (unsigned long) __bss_start;
553 bss_resource.end = (unsigned long) __bss_stop - 1;
554
555 for_each_mem_range(i, &start, &end) {
556 res = memblock_alloc(sizeof(*res), 8);
557 if (!res)
558 panic("%s: Failed to allocate %zu bytes align=0x%x\n",
559 __func__, sizeof(*res), 8);
560 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
561
562 res->name = "System RAM";
563 res->start = start;
564 /*
565 * In memblock, end points to the first byte after the
566 * range while in resourses, end points to the last byte in
567 * the range.
568 */
569 res->end = end - 1;
570 request_resource(&iomem_resource, res);
571
572 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
573 std_res = standard_resources[j];
574 if (std_res->start < res->start ||
575 std_res->start > res->end)
576 continue;
577 if (std_res->end > res->end) {
578 sub_res = memblock_alloc(sizeof(*sub_res), 8);
579 if (!sub_res)
580 panic("%s: Failed to allocate %zu bytes align=0x%x\n",
581 __func__, sizeof(*sub_res), 8);
582 *sub_res = *std_res;
583 sub_res->end = res->end;
584 std_res->start = res->end + 1;
585 request_resource(res, sub_res);
586 } else {
587 request_resource(res, std_res);
588 }
589 }
590 }
591 #ifdef CONFIG_CRASH_DUMP
592 /*
593 * Re-add removed crash kernel memory as reserved memory. This makes
594 * sure it will be mapped with the identity mapping and struct pages
595 * will be created, so it can be resized later on.
596 * However add it later since the crash kernel resource should not be
597 * part of the System RAM resource.
598 */
599 if (crashk_res.end) {
600 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
601 0, MEMBLOCK_NONE);
602 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
603 insert_resource(&iomem_resource, &crashk_res);
604 }
605 #endif
606 }
607
setup_memory_end(void)608 static void __init setup_memory_end(void)
609 {
610 memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
611 max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
612 pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
613 }
614
615 #ifdef CONFIG_CRASH_DUMP
616
617 /*
618 * When kdump is enabled, we have to ensure that no memory from the area
619 * [0 - crashkernel memory size] is set offline - it will be exchanged with
620 * the crashkernel memory region when kdump is triggered. The crashkernel
621 * memory region can never get offlined (pages are unmovable).
622 */
kdump_mem_notifier(struct notifier_block * nb,unsigned long action,void * data)623 static int kdump_mem_notifier(struct notifier_block *nb,
624 unsigned long action, void *data)
625 {
626 struct memory_notify *arg = data;
627
628 if (action != MEM_GOING_OFFLINE)
629 return NOTIFY_OK;
630 if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
631 return NOTIFY_BAD;
632 return NOTIFY_OK;
633 }
634
635 static struct notifier_block kdump_mem_nb = {
636 .notifier_call = kdump_mem_notifier,
637 };
638
639 #endif
640
641 /*
642 * Reserve memory for kdump kernel to be loaded with kexec
643 */
reserve_crashkernel(void)644 static void __init reserve_crashkernel(void)
645 {
646 #ifdef CONFIG_CRASH_DUMP
647 unsigned long long crash_base, crash_size;
648 phys_addr_t low, high;
649 int rc;
650
651 rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
652 &crash_base);
653
654 crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
655 crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
656 if (rc || crash_size == 0)
657 return;
658
659 if (memblock.memory.regions[0].size < crash_size) {
660 pr_info("crashkernel reservation failed: %s\n",
661 "first memory chunk must be at least crashkernel size");
662 return;
663 }
664
665 low = crash_base ?: oldmem_data.start;
666 high = low + crash_size;
667 if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
668 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
669 crash_base = low;
670 } else {
671 /* Find suitable area in free memory */
672 low = max_t(unsigned long, crash_size, sclp.hsa_size);
673 high = crash_base ? crash_base + crash_size : ULONG_MAX;
674
675 if (crash_base && crash_base < low) {
676 pr_info("crashkernel reservation failed: %s\n",
677 "crash_base too low");
678 return;
679 }
680 low = crash_base ?: low;
681 crash_base = memblock_phys_alloc_range(crash_size,
682 KEXEC_CRASH_MEM_ALIGN,
683 low, high);
684 }
685
686 if (!crash_base) {
687 pr_info("crashkernel reservation failed: %s\n",
688 "no suitable area found");
689 return;
690 }
691
692 if (register_memory_notifier(&kdump_mem_nb)) {
693 memblock_phys_free(crash_base, crash_size);
694 return;
695 }
696
697 if (!oldmem_data.start && MACHINE_IS_VM)
698 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
699 crashk_res.start = crash_base;
700 crashk_res.end = crash_base + crash_size - 1;
701 memblock_remove(crash_base, crash_size);
702 pr_info("Reserving %lluMB of memory at %lluMB "
703 "for crashkernel (System RAM: %luMB)\n",
704 crash_size >> 20, crash_base >> 20,
705 (unsigned long)memblock.memory.total_size >> 20);
706 os_info_crashkernel_add(crash_base, crash_size);
707 #endif
708 }
709
710 /*
711 * Reserve the initrd from being used by memblock
712 */
reserve_initrd(void)713 static void __init reserve_initrd(void)
714 {
715 #ifdef CONFIG_BLK_DEV_INITRD
716 if (!initrd_data.start || !initrd_data.size)
717 return;
718 initrd_start = (unsigned long)__va(initrd_data.start);
719 initrd_end = initrd_start + initrd_data.size;
720 memblock_reserve(initrd_data.start, initrd_data.size);
721 #endif
722 }
723
724 /*
725 * Reserve the memory area used to pass the certificate lists
726 */
reserve_certificate_list(void)727 static void __init reserve_certificate_list(void)
728 {
729 if (ipl_cert_list_addr)
730 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
731 }
732
reserve_mem_detect_info(void)733 static void __init reserve_mem_detect_info(void)
734 {
735 unsigned long start, size;
736
737 get_mem_detect_reserved(&start, &size);
738 if (size)
739 memblock_reserve(start, size);
740 }
741
free_mem_detect_info(void)742 static void __init free_mem_detect_info(void)
743 {
744 unsigned long start, size;
745
746 get_mem_detect_reserved(&start, &size);
747 if (size)
748 memblock_phys_free(start, size);
749 }
750
get_mem_info_source(void)751 static const char * __init get_mem_info_source(void)
752 {
753 switch (mem_detect.info_source) {
754 case MEM_DETECT_SCLP_STOR_INFO:
755 return "sclp storage info";
756 case MEM_DETECT_DIAG260:
757 return "diag260";
758 case MEM_DETECT_SCLP_READ_INFO:
759 return "sclp read info";
760 case MEM_DETECT_BIN_SEARCH:
761 return "binary search";
762 }
763 return "none";
764 }
765
memblock_add_mem_detect_info(void)766 static void __init memblock_add_mem_detect_info(void)
767 {
768 unsigned long start, end;
769 int i;
770
771 pr_debug("physmem info source: %s (%hhd)\n",
772 get_mem_info_source(), mem_detect.info_source);
773 /* keep memblock lists close to the kernel */
774 memblock_set_bottom_up(true);
775 for_each_mem_detect_block(i, &start, &end) {
776 memblock_add(start, end - start);
777 memblock_physmem_add(start, end - start);
778 }
779 memblock_set_bottom_up(false);
780 memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
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_phys_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 = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
874 if (!vmms)
875 panic("Failed to allocate memory for sysinfo structure\n");
876 if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
877 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
878 memblock_free(vmms, PAGE_SIZE);
879
880 #ifdef CONFIG_ARCH_RANDOM
881 if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
882 static_branch_enable(&s390_arch_random_available);
883 #endif
884 }
885
886 /*
887 * Find the correct size for the task_struct. This depends on
888 * the size of the struct fpu at the end of the thread_struct
889 * which is embedded in the task_struct.
890 */
setup_task_size(void)891 static void __init setup_task_size(void)
892 {
893 int task_size = sizeof(struct task_struct);
894
895 if (!MACHINE_HAS_VX) {
896 task_size -= sizeof(__vector128) * __NUM_VXRS;
897 task_size += sizeof(freg_t) * __NUM_FPRS;
898 }
899 arch_task_struct_size = task_size;
900 }
901
902 /*
903 * Issue diagnose 318 to set the control program name and
904 * version codes.
905 */
setup_control_program_code(void)906 static void __init setup_control_program_code(void)
907 {
908 union diag318_info diag318_info = {
909 .cpnc = CPNC_LINUX,
910 .cpvc = 0,
911 };
912
913 if (!sclp.has_diag318)
914 return;
915
916 diag_stat_inc(DIAG_STAT_X318);
917 asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
918 }
919
920 /*
921 * Print the component list from the IPL report
922 */
log_component_list(void)923 static void __init log_component_list(void)
924 {
925 struct ipl_rb_component_entry *ptr, *end;
926 char *str;
927
928 if (!early_ipl_comp_list_addr)
929 return;
930 if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
931 pr_info("Linux is running with Secure-IPL enabled\n");
932 else
933 pr_info("Linux is running with Secure-IPL disabled\n");
934 ptr = (void *) early_ipl_comp_list_addr;
935 end = (void *) ptr + early_ipl_comp_list_size;
936 pr_info("The IPL report contains the following components:\n");
937 while (ptr < end) {
938 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
939 if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
940 str = "signed, verified";
941 else
942 str = "signed, verification failed";
943 } else {
944 str = "not signed";
945 }
946 pr_info("%016llx - %016llx (%s)\n",
947 ptr->addr, ptr->addr + ptr->len, str);
948 ptr++;
949 }
950 }
951
952 /*
953 * Setup function called from init/main.c just after the banner
954 * was printed.
955 */
956
setup_arch(char ** cmdline_p)957 void __init setup_arch(char **cmdline_p)
958 {
959 /*
960 * print what head.S has found out about the machine
961 */
962 if (MACHINE_IS_VM)
963 pr_info("Linux is running as a z/VM "
964 "guest operating system in 64-bit mode\n");
965 else if (MACHINE_IS_KVM)
966 pr_info("Linux is running under KVM in 64-bit mode\n");
967 else if (MACHINE_IS_LPAR)
968 pr_info("Linux is running natively in 64-bit mode\n");
969 else
970 pr_info("Linux is running as a guest in 64-bit mode\n");
971
972 log_component_list();
973
974 /* Have one command line that is parsed and saved in /proc/cmdline */
975 /* boot_command_line has been already set up in early.c */
976 *cmdline_p = boot_command_line;
977
978 ROOT_DEV = Root_RAM0;
979
980 setup_initial_init_mm(_text, _etext, _edata, _end);
981
982 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
983 nospec_auto_detect();
984
985 jump_label_init();
986 parse_early_param();
987 #ifdef CONFIG_CRASH_DUMP
988 /* Deactivate elfcorehdr= kernel parameter */
989 elfcorehdr_addr = ELFCORE_ADDR_MAX;
990 #endif
991
992 os_info_init();
993 setup_ipl();
994 setup_task_size();
995 setup_control_program_code();
996
997 /* Do some memory reservations *before* memory is added to memblock */
998 reserve_kernel();
999 reserve_initrd();
1000 reserve_certificate_list();
1001 reserve_mem_detect_info();
1002 memblock_set_current_limit(ident_map_size);
1003 memblock_allow_resize();
1004
1005 /* Get information about *all* installed memory */
1006 memblock_add_mem_detect_info();
1007
1008 free_mem_detect_info();
1009 setup_memory_end();
1010 memblock_dump_all();
1011 setup_memory();
1012
1013 relocate_amode31_section();
1014 setup_cr();
1015 setup_uv();
1016 dma_contiguous_reserve(ident_map_size);
1017 vmcp_cma_reserve();
1018 if (MACHINE_HAS_EDAT2)
1019 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1020
1021 check_initrd();
1022 reserve_crashkernel();
1023 #ifdef CONFIG_CRASH_DUMP
1024 /*
1025 * Be aware that smp_save_dump_cpus() triggers a system reset.
1026 * Therefore CPU and device initialization should be done afterwards.
1027 */
1028 smp_save_dump_cpus();
1029 #endif
1030
1031 setup_resources();
1032 setup_lowcore_dat_off();
1033 smp_fill_possible_mask();
1034 cpu_detect_mhz_feature();
1035 cpu_init();
1036 numa_setup();
1037 smp_detect_cpus();
1038 topology_init_early();
1039
1040 if (test_facility(193))
1041 static_branch_enable(&cpu_has_bear);
1042
1043 /*
1044 * Create kernel page tables and switch to virtual addressing.
1045 */
1046 paging_init();
1047
1048 /*
1049 * After paging_init created the kernel page table, the new PSWs
1050 * in lowcore can now run with DAT enabled.
1051 */
1052 setup_lowcore_dat_on();
1053
1054 /* Setup default console */
1055 conmode_default();
1056 set_preferred_console();
1057
1058 apply_alternative_instructions();
1059 if (IS_ENABLED(CONFIG_EXPOLINE))
1060 nospec_init_branches();
1061
1062 /* Setup zfcp/nvme dump support */
1063 setup_zfcpdump();
1064
1065 /* Add system specific data to the random pool */
1066 setup_randomness();
1067 }
1068