1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright IBM Corp. 1999, 2012
5 * Author(s): Hartmut Penner (hp@de.ibm.com),
6 * Martin Schwidefsky (schwidefsky@de.ibm.com)
8 * Derived from "arch/i386/kernel/setup.c"
9 * Copyright (C) 1995, Linus Torvalds
13 * This file handles the architecture-dependent parts of initialization
16 #define KMSG_COMPONENT "setup"
17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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>
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/bootmem.h>
38 #include <linux/root_dev.h>
39 #include <linux/console.h>
40 #include <linux/kernel_stat.h>
41 #include <linux/dma-contiguous.h>
42 #include <linux/device.h>
43 #include <linux/notifier.h>
44 #include <linux/pfn.h>
45 #include <linux/ctype.h>
46 #include <linux/reboot.h>
47 #include <linux/topology.h>
48 #include <linux/kexec.h>
49 #include <linux/crash_dump.h>
50 #include <linux/memory.h>
51 #include <linux/compat.h>
54 #include <asm/facility.h>
56 #include <asm/mmu_context.h>
57 #include <asm/cpcmd.h>
58 #include <asm/lowcore.h>
62 #include <asm/ptrace.h>
63 #include <asm/sections.h>
64 #include <asm/ebcdic.h>
66 #include <asm/os_info.h>
68 #include <asm/sysinfo.h>
70 #include <asm/alternative.h>
71 #include <asm/nospec-branch.h>
77 unsigned int console_mode
= 0;
78 EXPORT_SYMBOL(console_mode
);
80 unsigned int console_devno
= -1;
81 EXPORT_SYMBOL(console_devno
);
83 unsigned int console_irq
= -1;
84 EXPORT_SYMBOL(console_irq
);
86 unsigned long elf_hwcap __read_mostly
= 0;
87 char elf_platform
[ELF_PLATFORM_SIZE
];
89 unsigned long int_hwcap
= 0;
91 int __initdata memory_end_set
;
92 unsigned long __initdata memory_end
;
93 unsigned long __initdata max_physmem_end
;
95 unsigned long VMALLOC_START
;
96 EXPORT_SYMBOL(VMALLOC_START
);
98 unsigned long VMALLOC_END
;
99 EXPORT_SYMBOL(VMALLOC_END
);
101 struct page
*vmemmap
;
102 EXPORT_SYMBOL(vmemmap
);
104 unsigned long MODULES_VADDR
;
105 unsigned long MODULES_END
;
107 /* An array with a pointer to the lowcore of every CPU. */
108 struct lowcore
*lowcore_ptr
[NR_CPUS
];
109 EXPORT_SYMBOL(lowcore_ptr
);
112 * This is set up by the setup-routine at boot-time
113 * for S390 need to find out, what we have to setup
114 * using address 0x10400 ...
117 #include <asm/setup.h>
120 * condev= and conmode= setup parameter.
123 static int __init
condev_setup(char *str
)
127 vdev
= simple_strtoul(str
, &str
, 0);
128 if (vdev
>= 0 && vdev
< 65536) {
129 console_devno
= vdev
;
135 __setup("condev=", condev_setup
);
137 static void __init
set_preferred_console(void)
139 if (CONSOLE_IS_3215
|| CONSOLE_IS_SCLP
)
140 add_preferred_console("ttyS", 0, NULL
);
141 else if (CONSOLE_IS_3270
)
142 add_preferred_console("tty3270", 0, NULL
);
143 else if (CONSOLE_IS_VT220
)
144 add_preferred_console("ttyS", 1, NULL
);
145 else if (CONSOLE_IS_HVC
)
146 add_preferred_console("hvc", 0, NULL
);
149 static int __init
conmode_setup(char *str
)
151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
152 if (strncmp(str
, "hwc", 4) == 0 || strncmp(str
, "sclp", 5) == 0)
155 #if defined(CONFIG_TN3215_CONSOLE)
156 if (strncmp(str
, "3215", 5) == 0)
159 #if defined(CONFIG_TN3270_CONSOLE)
160 if (strncmp(str
, "3270", 5) == 0)
163 set_preferred_console();
167 __setup("conmode=", conmode_setup
);
169 static void __init
conmode_default(void)
171 char query_buffer
[1024];
175 cpcmd("QUERY CONSOLE", query_buffer
, 1024, NULL
);
176 console_devno
= simple_strtoul(query_buffer
+ 5, NULL
, 16);
177 ptr
= strstr(query_buffer
, "SUBCHANNEL =");
178 console_irq
= simple_strtoul(ptr
+ 13, NULL
, 16);
179 cpcmd("QUERY TERM", query_buffer
, 1024, NULL
);
180 ptr
= strstr(query_buffer
, "CONMODE");
182 * Set the conmode to 3215 so that the device recognition
183 * will set the cu_type of the console to 3215. If the
184 * conmode is 3270 and we don't set it back then both
185 * 3215 and the 3270 driver will try to access the console
186 * device (3215 as console and 3270 as normal tty).
188 cpcmd("TERM CONMODE 3215", NULL
, 0, NULL
);
190 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
195 if (strncmp(ptr
+ 8, "3270", 4) == 0) {
196 #if defined(CONFIG_TN3270_CONSOLE)
198 #elif defined(CONFIG_TN3215_CONSOLE)
200 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
203 } else if (strncmp(ptr
+ 8, "3215", 4) == 0) {
204 #if defined(CONFIG_TN3215_CONSOLE)
206 #elif defined(CONFIG_TN3270_CONSOLE)
208 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
212 } else if (MACHINE_IS_KVM
) {
213 if (sclp
.has_vt220
&& IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE
))
215 else if (sclp
.has_linemode
&& IS_ENABLED(CONFIG_SCLP_CONSOLE
))
220 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
226 #ifdef CONFIG_CRASH_DUMP
227 static void __init
setup_zfcpdump(void)
229 if (ipl_info
.type
!= IPL_TYPE_FCP_DUMP
)
233 strcat(boot_command_line
, " cio_ignore=all,!ipldev,!condev");
234 console_loglevel
= 2;
237 static inline void setup_zfcpdump(void) {}
238 #endif /* CONFIG_CRASH_DUMP */
241 * Reboot, halt and power_off stubs. They just call _machine_restart,
242 * _machine_halt or _machine_power_off.
245 void machine_restart(char *command
)
247 if ((!in_interrupt() && !in_atomic()) || oops_in_progress
)
249 * Only unblank the console if we are called in enabled
250 * context or a bust_spinlocks cleared the way for us.
253 _machine_restart(command
);
256 void machine_halt(void)
258 if (!in_interrupt() || oops_in_progress
)
260 * Only unblank the console if we are called in enabled
261 * context or a bust_spinlocks cleared the way for us.
267 void machine_power_off(void)
269 if (!in_interrupt() || oops_in_progress
)
271 * Only unblank the console if we are called in enabled
272 * context or a bust_spinlocks cleared the way for us.
275 _machine_power_off();
279 * Dummy power off function.
281 void (*pm_power_off
)(void) = machine_power_off
;
282 EXPORT_SYMBOL_GPL(pm_power_off
);
284 static int __init
early_parse_mem(char *p
)
286 memory_end
= memparse(p
, &p
);
287 memory_end
&= PAGE_MASK
;
291 early_param("mem", early_parse_mem
);
293 static int __init
parse_vmalloc(char *arg
)
297 VMALLOC_END
= (memparse(arg
, &arg
) + PAGE_SIZE
- 1) & PAGE_MASK
;
300 early_param("vmalloc", parse_vmalloc
);
302 void *restart_stack
__section(.data
);
304 static void __init
setup_lowcore_dat_off(void)
309 * Setup lowcore for boot cpu
311 BUILD_BUG_ON(sizeof(struct lowcore
) != LC_PAGES
* PAGE_SIZE
);
312 lc
= memblock_virt_alloc_low(sizeof(*lc
), sizeof(*lc
));
313 lc
->restart_psw
.mask
= PSW_KERNEL_BITS
;
314 lc
->restart_psw
.addr
= (unsigned long) restart_int_handler
;
315 lc
->external_new_psw
.mask
= PSW_KERNEL_BITS
| PSW_MASK_MCHECK
;
316 lc
->external_new_psw
.addr
= (unsigned long) ext_int_handler
;
317 lc
->svc_new_psw
.mask
= PSW_KERNEL_BITS
|
318 PSW_MASK_IO
| PSW_MASK_EXT
| PSW_MASK_MCHECK
;
319 lc
->svc_new_psw
.addr
= (unsigned long) system_call
;
320 lc
->program_new_psw
.mask
= PSW_KERNEL_BITS
| PSW_MASK_MCHECK
;
321 lc
->program_new_psw
.addr
= (unsigned long) pgm_check_handler
;
322 lc
->mcck_new_psw
.mask
= PSW_KERNEL_BITS
;
323 lc
->mcck_new_psw
.addr
= (unsigned long) mcck_int_handler
;
324 lc
->io_new_psw
.mask
= PSW_KERNEL_BITS
| PSW_MASK_MCHECK
;
325 lc
->io_new_psw
.addr
= (unsigned long) io_int_handler
;
326 lc
->clock_comparator
= clock_comparator_max
;
327 lc
->kernel_stack
= ((unsigned long) &init_thread_union
)
328 + THREAD_SIZE
- STACK_FRAME_OVERHEAD
- sizeof(struct pt_regs
);
329 lc
->async_stack
= (unsigned long)
330 memblock_virt_alloc(ASYNC_SIZE
, ASYNC_SIZE
)
331 + ASYNC_SIZE
- STACK_FRAME_OVERHEAD
- sizeof(struct pt_regs
);
332 lc
->panic_stack
= (unsigned long)
333 memblock_virt_alloc(PAGE_SIZE
, PAGE_SIZE
)
334 + PAGE_SIZE
- STACK_FRAME_OVERHEAD
- sizeof(struct pt_regs
);
335 lc
->current_task
= (unsigned long)&init_task
;
337 lc
->machine_flags
= S390_lowcore
.machine_flags
;
338 lc
->preempt_count
= S390_lowcore
.preempt_count
;
339 lc
->stfl_fac_list
= S390_lowcore
.stfl_fac_list
;
340 memcpy(lc
->stfle_fac_list
, S390_lowcore
.stfle_fac_list
,
341 sizeof(lc
->stfle_fac_list
));
342 memcpy(lc
->alt_stfle_fac_list
, S390_lowcore
.alt_stfle_fac_list
,
343 sizeof(lc
->alt_stfle_fac_list
));
344 nmi_alloc_boot_cpu(lc
);
345 vdso_alloc_boot_cpu(lc
);
346 lc
->sync_enter_timer
= S390_lowcore
.sync_enter_timer
;
347 lc
->async_enter_timer
= S390_lowcore
.async_enter_timer
;
348 lc
->exit_timer
= S390_lowcore
.exit_timer
;
349 lc
->user_timer
= S390_lowcore
.user_timer
;
350 lc
->system_timer
= S390_lowcore
.system_timer
;
351 lc
->steal_timer
= S390_lowcore
.steal_timer
;
352 lc
->last_update_timer
= S390_lowcore
.last_update_timer
;
353 lc
->last_update_clock
= S390_lowcore
.last_update_clock
;
355 restart_stack
= memblock_virt_alloc(ASYNC_SIZE
, ASYNC_SIZE
);
356 restart_stack
+= ASYNC_SIZE
;
359 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
360 * restart data to the absolute zero lowcore. This is necessary if
361 * PSW restart is done on an offline CPU that has lowcore zero.
363 lc
->restart_stack
= (unsigned long) restart_stack
;
364 lc
->restart_fn
= (unsigned long) do_restart
;
365 lc
->restart_data
= 0;
366 lc
->restart_source
= -1UL;
368 /* Setup absolute zero lowcore */
369 mem_assign_absolute(S390_lowcore
.restart_stack
, lc
->restart_stack
);
370 mem_assign_absolute(S390_lowcore
.restart_fn
, lc
->restart_fn
);
371 mem_assign_absolute(S390_lowcore
.restart_data
, lc
->restart_data
);
372 mem_assign_absolute(S390_lowcore
.restart_source
, lc
->restart_source
);
373 mem_assign_absolute(S390_lowcore
.restart_psw
, lc
->restart_psw
);
376 lc
->spinlock_lockval
= arch_spin_lockval(0);
377 lc
->spinlock_index
= 0;
378 arch_spin_lock_setup(0);
380 lc
->br_r1_trampoline
= 0x07f1; /* br %r1 */
382 set_prefix((u32
)(unsigned long) lc
);
386 static void __init
setup_lowcore_dat_on(void)
391 lc
->external_new_psw
.mask
|= PSW_MASK_DAT
;
392 lc
->svc_new_psw
.mask
|= PSW_MASK_DAT
;
393 lc
->program_new_psw
.mask
|= PSW_MASK_DAT
;
394 lc
->io_new_psw
.mask
|= PSW_MASK_DAT
;
397 static struct resource code_resource
= {
398 .name
= "Kernel code",
399 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
402 static struct resource data_resource
= {
403 .name
= "Kernel data",
404 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
407 static struct resource bss_resource
= {
408 .name
= "Kernel bss",
409 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
412 static struct resource __initdata
*standard_resources
[] = {
418 static void __init
setup_resources(void)
420 struct resource
*res
, *std_res
, *sub_res
;
421 struct memblock_region
*reg
;
424 code_resource
.start
= (unsigned long) &_text
;
425 code_resource
.end
= (unsigned long) &_etext
- 1;
426 data_resource
.start
= (unsigned long) &_etext
;
427 data_resource
.end
= (unsigned long) &_edata
- 1;
428 bss_resource
.start
= (unsigned long) &__bss_start
;
429 bss_resource
.end
= (unsigned long) &__bss_stop
- 1;
431 for_each_memblock(memory
, reg
) {
432 res
= memblock_virt_alloc(sizeof(*res
), 8);
433 res
->flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
;
435 res
->name
= "System RAM";
436 res
->start
= reg
->base
;
437 res
->end
= reg
->base
+ reg
->size
- 1;
438 request_resource(&iomem_resource
, res
);
440 for (j
= 0; j
< ARRAY_SIZE(standard_resources
); j
++) {
441 std_res
= standard_resources
[j
];
442 if (std_res
->start
< res
->start
||
443 std_res
->start
> res
->end
)
445 if (std_res
->end
> res
->end
) {
446 sub_res
= memblock_virt_alloc(sizeof(*sub_res
), 8);
448 sub_res
->end
= res
->end
;
449 std_res
->start
= res
->end
+ 1;
450 request_resource(res
, sub_res
);
452 request_resource(res
, std_res
);
456 #ifdef CONFIG_CRASH_DUMP
458 * Re-add removed crash kernel memory as reserved memory. This makes
459 * sure it will be mapped with the identity mapping and struct pages
460 * will be created, so it can be resized later on.
461 * However add it later since the crash kernel resource should not be
462 * part of the System RAM resource.
464 if (crashk_res
.end
) {
465 memblock_add_node(crashk_res
.start
, resource_size(&crashk_res
), 0);
466 memblock_reserve(crashk_res
.start
, resource_size(&crashk_res
));
467 insert_resource(&iomem_resource
, &crashk_res
);
472 static void __init
setup_memory_end(void)
474 unsigned long vmax
, vmalloc_size
, tmp
;
476 /* Choose kernel address space layout: 2, 3, or 4 levels. */
477 vmalloc_size
= VMALLOC_END
?: (128UL << 30) - MODULES_LEN
;
478 tmp
= (memory_end
?: max_physmem_end
) / PAGE_SIZE
;
479 tmp
= tmp
* (sizeof(struct page
) + PAGE_SIZE
);
480 if (tmp
+ vmalloc_size
+ MODULES_LEN
<= _REGION2_SIZE
)
481 vmax
= _REGION2_SIZE
; /* 3-level kernel page table */
483 vmax
= _REGION1_SIZE
; /* 4-level kernel page table */
484 /* module area is at the end of the kernel address space. */
486 MODULES_VADDR
= MODULES_END
- MODULES_LEN
;
487 VMALLOC_END
= MODULES_VADDR
;
488 VMALLOC_START
= vmax
- vmalloc_size
;
490 /* Split remaining virtual space between 1:1 mapping & vmemmap array */
491 tmp
= VMALLOC_START
/ (PAGE_SIZE
+ sizeof(struct page
));
492 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
493 tmp
= SECTION_ALIGN_UP(tmp
);
494 tmp
= VMALLOC_START
- tmp
* sizeof(struct page
);
495 tmp
&= ~((vmax
>> 11) - 1); /* align to page table level */
496 tmp
= min(tmp
, 1UL << MAX_PHYSMEM_BITS
);
497 vmemmap
= (struct page
*) tmp
;
499 /* Take care that memory_end is set and <= vmemmap */
500 memory_end
= min(memory_end
?: max_physmem_end
, tmp
);
501 max_pfn
= max_low_pfn
= PFN_DOWN(memory_end
);
502 memblock_remove(memory_end
, ULONG_MAX
);
504 pr_notice("The maximum memory size is %luMB\n", memory_end
>> 20);
507 #ifdef CONFIG_CRASH_DUMP
510 * When kdump is enabled, we have to ensure that no memory from
511 * the area [0 - crashkernel memory size] and
512 * [crashk_res.start - crashk_res.end] is set offline.
514 static int kdump_mem_notifier(struct notifier_block
*nb
,
515 unsigned long action
, void *data
)
517 struct memory_notify
*arg
= data
;
519 if (action
!= MEM_GOING_OFFLINE
)
521 if (arg
->start_pfn
< PFN_DOWN(resource_size(&crashk_res
)))
523 if (arg
->start_pfn
> PFN_DOWN(crashk_res
.end
))
525 if (arg
->start_pfn
+ arg
->nr_pages
- 1 < PFN_DOWN(crashk_res
.start
))
530 static struct notifier_block kdump_mem_nb
= {
531 .notifier_call
= kdump_mem_notifier
,
537 * Make sure that the area behind memory_end is protected
539 static void reserve_memory_end(void)
541 #ifdef CONFIG_CRASH_DUMP
542 if (ipl_info
.type
== IPL_TYPE_FCP_DUMP
&&
543 !OLDMEM_BASE
&& sclp
.hsa_size
) {
544 memory_end
= sclp
.hsa_size
;
545 memory_end
&= PAGE_MASK
;
551 memblock_reserve(memory_end
, ULONG_MAX
);
555 * Make sure that oldmem, where the dump is stored, is protected
557 static void reserve_oldmem(void)
559 #ifdef CONFIG_CRASH_DUMP
561 /* Forget all memory above the running kdump system */
562 memblock_reserve(OLDMEM_SIZE
, (phys_addr_t
)ULONG_MAX
);
567 * Make sure that oldmem, where the dump is stored, is protected
569 static void remove_oldmem(void)
571 #ifdef CONFIG_CRASH_DUMP
573 /* Forget all memory above the running kdump system */
574 memblock_remove(OLDMEM_SIZE
, (phys_addr_t
)ULONG_MAX
);
579 * Reserve memory for kdump kernel to be loaded with kexec
581 static void __init
reserve_crashkernel(void)
583 #ifdef CONFIG_CRASH_DUMP
584 unsigned long long crash_base
, crash_size
;
585 phys_addr_t low
, high
;
588 rc
= parse_crashkernel(boot_command_line
, memory_end
, &crash_size
,
591 crash_base
= ALIGN(crash_base
, KEXEC_CRASH_MEM_ALIGN
);
592 crash_size
= ALIGN(crash_size
, KEXEC_CRASH_MEM_ALIGN
);
593 if (rc
|| crash_size
== 0)
596 if (memblock
.memory
.regions
[0].size
< crash_size
) {
597 pr_info("crashkernel reservation failed: %s\n",
598 "first memory chunk must be at least crashkernel size");
602 low
= crash_base
?: OLDMEM_BASE
;
603 high
= low
+ crash_size
;
604 if (low
>= OLDMEM_BASE
&& high
<= OLDMEM_BASE
+ OLDMEM_SIZE
) {
605 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
608 /* Find suitable area in free memory */
609 low
= max_t(unsigned long, crash_size
, sclp
.hsa_size
);
610 high
= crash_base
? crash_base
+ crash_size
: ULONG_MAX
;
612 if (crash_base
&& crash_base
< low
) {
613 pr_info("crashkernel reservation failed: %s\n",
614 "crash_base too low");
617 low
= crash_base
?: low
;
618 crash_base
= memblock_find_in_range(low
, high
, crash_size
,
619 KEXEC_CRASH_MEM_ALIGN
);
623 pr_info("crashkernel reservation failed: %s\n",
624 "no suitable area found");
628 if (register_memory_notifier(&kdump_mem_nb
))
631 if (!OLDMEM_BASE
&& MACHINE_IS_VM
)
632 diag10_range(PFN_DOWN(crash_base
), PFN_DOWN(crash_size
));
633 crashk_res
.start
= crash_base
;
634 crashk_res
.end
= crash_base
+ crash_size
- 1;
635 memblock_remove(crash_base
, crash_size
);
636 pr_info("Reserving %lluMB of memory at %lluMB "
637 "for crashkernel (System RAM: %luMB)\n",
638 crash_size
>> 20, crash_base
>> 20,
639 (unsigned long)memblock
.memory
.total_size
>> 20);
640 os_info_crashkernel_add(crash_base
, crash_size
);
645 * Reserve the initrd from being used by memblock
647 static void __init
reserve_initrd(void)
649 #ifdef CONFIG_BLK_DEV_INITRD
650 if (!INITRD_START
|| !INITRD_SIZE
)
652 initrd_start
= INITRD_START
;
653 initrd_end
= initrd_start
+ INITRD_SIZE
;
654 memblock_reserve(INITRD_START
, INITRD_SIZE
);
659 * Check for initrd being in usable memory
661 static void __init
check_initrd(void)
663 #ifdef CONFIG_BLK_DEV_INITRD
664 if (INITRD_START
&& INITRD_SIZE
&&
665 !memblock_is_region_memory(INITRD_START
, INITRD_SIZE
)) {
666 pr_err("The initial RAM disk does not fit into the memory\n");
667 memblock_free(INITRD_START
, INITRD_SIZE
);
668 initrd_start
= initrd_end
= 0;
674 * Reserve memory used for lowcore/command line/kernel image.
676 static void __init
reserve_kernel(void)
678 unsigned long start_pfn
= PFN_UP(__pa(&_end
));
680 #ifdef CONFIG_DMA_API_DEBUG
682 * DMA_API_DEBUG code stumbles over addresses from the
683 * range [_ehead, _stext]. Mark the memory as reserved
684 * so it is not used for CONFIG_DMA_API_DEBUG=y.
686 memblock_reserve(0, PFN_PHYS(start_pfn
));
688 memblock_reserve(0, (unsigned long)_ehead
);
689 memblock_reserve((unsigned long)_stext
, PFN_PHYS(start_pfn
)
690 - (unsigned long)_stext
);
694 static void __init
setup_memory(void)
696 struct memblock_region
*reg
;
699 * Init storage key for present memory
701 for_each_memblock(memory
, reg
) {
702 storage_key_init_range(reg
->base
, reg
->base
+ reg
->size
);
704 psw_set_key(PAGE_DEFAULT_KEY
);
707 memblock_enforce_memory_limit(memblock_end_of_DRAM());
711 * Setup hardware capabilities.
713 static int __init
setup_hwcaps(void)
715 static const int stfl_bits
[6] = { 0, 2, 7, 17, 19, 21 };
720 * The store facility list bits numbers as found in the principles
721 * of operation are numbered with bit 1UL<<31 as number 0 to
722 * bit 1UL<<0 as number 31.
723 * Bit 0: instructions named N3, "backported" to esa-mode
724 * Bit 2: z/Architecture mode is active
725 * Bit 7: the store-facility-list-extended facility is installed
726 * Bit 17: the message-security assist is installed
727 * Bit 19: the long-displacement facility is installed
728 * Bit 21: the extended-immediate facility is installed
729 * Bit 22: extended-translation facility 3 is installed
730 * Bit 30: extended-translation facility 3 enhancement facility
731 * These get translated to:
732 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
733 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
734 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
735 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
737 for (i
= 0; i
< 6; i
++)
738 if (test_facility(stfl_bits
[i
]))
739 elf_hwcap
|= 1UL << i
;
741 if (test_facility(22) && test_facility(30))
742 elf_hwcap
|= HWCAP_S390_ETF3EH
;
745 * Check for additional facilities with store-facility-list-extended.
746 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
747 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
748 * as stored by stfl, bits 32-xxx contain additional facilities.
749 * How many facility words are stored depends on the number of
750 * doublewords passed to the instruction. The additional facilities
752 * Bit 42: decimal floating point facility is installed
753 * Bit 44: perform floating point operation facility is installed
755 * HWCAP_S390_DFP bit 6 (42 && 44).
757 if ((elf_hwcap
& (1UL << 2)) && test_facility(42) && test_facility(44))
758 elf_hwcap
|= HWCAP_S390_DFP
;
761 * Huge page support HWCAP_S390_HPAGE is bit 7.
763 if (MACHINE_HAS_EDAT1
)
764 elf_hwcap
|= HWCAP_S390_HPAGE
;
767 * 64-bit register support for 31-bit processes
768 * HWCAP_S390_HIGH_GPRS is bit 9.
770 elf_hwcap
|= HWCAP_S390_HIGH_GPRS
;
773 * Transactional execution support HWCAP_S390_TE is bit 10.
776 elf_hwcap
|= HWCAP_S390_TE
;
779 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
780 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
781 * instead of facility bit 129.
783 if (MACHINE_HAS_VX
) {
784 elf_hwcap
|= HWCAP_S390_VXRS
;
785 if (test_facility(134))
786 elf_hwcap
|= HWCAP_S390_VXRS_EXT
;
787 if (test_facility(135))
788 elf_hwcap
|= HWCAP_S390_VXRS_BCD
;
792 * Guarded storage support HWCAP_S390_GS is bit 12.
795 elf_hwcap
|= HWCAP_S390_GS
;
798 add_device_randomness(&cpu_id
, sizeof(cpu_id
));
799 switch (cpu_id
.machine
) {
802 default: /* Use "z900" as default for 64 bit kernels. */
803 strcpy(elf_platform
, "z900");
807 strcpy(elf_platform
, "z990");
811 strcpy(elf_platform
, "z9-109");
815 strcpy(elf_platform
, "z10");
819 strcpy(elf_platform
, "z196");
823 strcpy(elf_platform
, "zEC12");
827 strcpy(elf_platform
, "z13");
831 strcpy(elf_platform
, "z14");
836 * Virtualization support HWCAP_INT_SIE is bit 0.
839 int_hwcap
|= HWCAP_INT_SIE
;
843 arch_initcall(setup_hwcaps
);
846 * Add system information as device randomness
848 static void __init
setup_randomness(void)
850 struct sysinfo_3_2_2
*vmms
;
852 vmms
= (struct sysinfo_3_2_2
*) memblock_alloc(PAGE_SIZE
, PAGE_SIZE
);
853 if (stsi(vmms
, 3, 2, 2) == 0 && vmms
->count
)
854 add_device_randomness(&vmms
->vm
, sizeof(vmms
->vm
[0]) * vmms
->count
);
855 memblock_free((unsigned long) vmms
, PAGE_SIZE
);
859 * Find the correct size for the task_struct. This depends on
860 * the size of the struct fpu at the end of the thread_struct
861 * which is embedded in the task_struct.
863 static void __init
setup_task_size(void)
865 int task_size
= sizeof(struct task_struct
);
867 if (!MACHINE_HAS_VX
) {
868 task_size
-= sizeof(__vector128
) * __NUM_VXRS
;
869 task_size
+= sizeof(freg_t
) * __NUM_FPRS
;
871 arch_task_struct_size
= task_size
;
875 * Setup function called from init/main.c just after the banner
879 void __init
setup_arch(char **cmdline_p
)
882 * print what head.S has found out about the machine
885 pr_info("Linux is running as a z/VM "
886 "guest operating system in 64-bit mode\n");
887 else if (MACHINE_IS_KVM
)
888 pr_info("Linux is running under KVM in 64-bit mode\n");
889 else if (MACHINE_IS_LPAR
)
890 pr_info("Linux is running natively in 64-bit mode\n");
892 pr_info("Linux is running as a guest in 64-bit mode\n");
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
;
898 ROOT_DEV
= Root_RAM0
;
900 /* Is init_mm really needed? */
901 init_mm
.start_code
= PAGE_OFFSET
;
902 init_mm
.end_code
= (unsigned long) &_etext
;
903 init_mm
.end_data
= (unsigned long) &_edata
;
904 init_mm
.brk
= (unsigned long) &_end
;
906 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO
))
907 nospec_auto_detect();
910 #ifdef CONFIG_CRASH_DUMP
911 /* Deactivate elfcorehdr= kernel parameter */
912 elfcorehdr_addr
= ELFCORE_ADDR_MAX
;
919 /* Do some memory reservations *before* memory is added to memblock */
920 reserve_memory_end();
924 memblock_allow_resize();
926 /* Get information about *all* installed memory */
927 detect_memory_memblock();
932 * Make sure all chunks are MAX_ORDER aligned so we don't need the
933 * extra checks that HOLES_IN_ZONE would require.
935 * Is this still required?
937 memblock_trim_memory(1UL << (MAX_ORDER
- 1 + PAGE_SHIFT
));
941 dma_contiguous_reserve(memory_end
);
945 reserve_crashkernel();
946 #ifdef CONFIG_CRASH_DUMP
948 * Be aware that smp_save_dump_cpus() triggers a system reset.
949 * Therefore CPU and device initialization should be done afterwards.
951 smp_save_dump_cpus();
955 setup_lowcore_dat_off();
956 smp_fill_possible_mask();
957 cpu_detect_mhz_feature();
961 topology_init_early();
964 * Create kernel page tables and switch to virtual addressing.
969 * After paging_init created the kernel page table, the new PSWs
970 * in lowcore can now run with DAT enabled.
972 setup_lowcore_dat_on();
974 /* Setup default console */
976 set_preferred_console();
978 apply_alternative_instructions();
979 if (IS_ENABLED(CONFIG_EXPOLINE
))
980 nospec_init_branches();
982 /* Setup zfcpdump support */
985 /* Add system specific data to the random pool */