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/root_dev.h>
38 #include <linux/console.h>
39 #include <linux/kernel_stat.h>
40 #include <linux/dma-contiguous.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>
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>
72 #include <asm/mem_detect.h>
78 unsigned int console_mode
= 0;
79 EXPORT_SYMBOL(console_mode
);
81 unsigned int console_devno
= -1;
82 EXPORT_SYMBOL(console_devno
);
84 unsigned int console_irq
= -1;
85 EXPORT_SYMBOL(console_irq
);
87 unsigned long elf_hwcap __read_mostly
= 0;
88 char elf_platform
[ELF_PLATFORM_SIZE
];
90 unsigned long int_hwcap
= 0;
92 int __bootdata(noexec_disabled
);
93 int __bootdata(memory_end_set
);
94 unsigned long __bootdata(memory_end
);
95 unsigned long __bootdata(max_physmem_end
);
96 struct mem_detect_info
__bootdata(mem_detect
);
98 unsigned long VMALLOC_START
;
99 EXPORT_SYMBOL(VMALLOC_START
);
101 unsigned long VMALLOC_END
;
102 EXPORT_SYMBOL(VMALLOC_END
);
104 struct page
*vmemmap
;
105 EXPORT_SYMBOL(vmemmap
);
107 unsigned long MODULES_VADDR
;
108 unsigned long MODULES_END
;
110 /* An array with a pointer to the lowcore of every CPU. */
111 struct lowcore
*lowcore_ptr
[NR_CPUS
];
112 EXPORT_SYMBOL(lowcore_ptr
);
115 * This is set up by the setup-routine at boot-time
116 * for S390 need to find out, what we have to setup
117 * using address 0x10400 ...
120 #include <asm/setup.h>
123 * condev= and conmode= setup parameter.
126 static int __init
condev_setup(char *str
)
130 vdev
= simple_strtoul(str
, &str
, 0);
131 if (vdev
>= 0 && vdev
< 65536) {
132 console_devno
= vdev
;
138 __setup("condev=", condev_setup
);
140 static void __init
set_preferred_console(void)
142 if (CONSOLE_IS_3215
|| CONSOLE_IS_SCLP
)
143 add_preferred_console("ttyS", 0, NULL
);
144 else if (CONSOLE_IS_3270
)
145 add_preferred_console("tty3270", 0, NULL
);
146 else if (CONSOLE_IS_VT220
)
147 add_preferred_console("ttyS", 1, NULL
);
148 else if (CONSOLE_IS_HVC
)
149 add_preferred_console("hvc", 0, NULL
);
152 static int __init
conmode_setup(char *str
)
154 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
155 if (strncmp(str
, "hwc", 4) == 0 || strncmp(str
, "sclp", 5) == 0)
158 #if defined(CONFIG_TN3215_CONSOLE)
159 if (strncmp(str
, "3215", 5) == 0)
162 #if defined(CONFIG_TN3270_CONSOLE)
163 if (strncmp(str
, "3270", 5) == 0)
166 set_preferred_console();
170 __setup("conmode=", conmode_setup
);
172 static void __init
conmode_default(void)
174 char query_buffer
[1024];
178 cpcmd("QUERY CONSOLE", query_buffer
, 1024, NULL
);
179 console_devno
= simple_strtoul(query_buffer
+ 5, NULL
, 16);
180 ptr
= strstr(query_buffer
, "SUBCHANNEL =");
181 console_irq
= simple_strtoul(ptr
+ 13, NULL
, 16);
182 cpcmd("QUERY TERM", query_buffer
, 1024, NULL
);
183 ptr
= strstr(query_buffer
, "CONMODE");
185 * Set the conmode to 3215 so that the device recognition
186 * will set the cu_type of the console to 3215. If the
187 * conmode is 3270 and we don't set it back then both
188 * 3215 and the 3270 driver will try to access the console
189 * device (3215 as console and 3270 as normal tty).
191 cpcmd("TERM CONMODE 3215", NULL
, 0, NULL
);
193 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
198 if (strncmp(ptr
+ 8, "3270", 4) == 0) {
199 #if defined(CONFIG_TN3270_CONSOLE)
201 #elif defined(CONFIG_TN3215_CONSOLE)
203 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
206 } else if (strncmp(ptr
+ 8, "3215", 4) == 0) {
207 #if defined(CONFIG_TN3215_CONSOLE)
209 #elif defined(CONFIG_TN3270_CONSOLE)
211 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
215 } else if (MACHINE_IS_KVM
) {
216 if (sclp
.has_vt220
&& IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE
))
218 else if (sclp
.has_linemode
&& IS_ENABLED(CONFIG_SCLP_CONSOLE
))
223 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
227 if (IS_ENABLED(CONFIG_VT
) && IS_ENABLED(CONFIG_DUMMY_CONSOLE
))
228 conswitchp
= &dummy_con
;
231 #ifdef CONFIG_CRASH_DUMP
232 static void __init
setup_zfcpdump(void)
234 if (ipl_info
.type
!= IPL_TYPE_FCP_DUMP
)
238 strcat(boot_command_line
, " cio_ignore=all,!ipldev,!condev");
239 console_loglevel
= 2;
242 static inline void setup_zfcpdump(void) {}
243 #endif /* CONFIG_CRASH_DUMP */
246 * Reboot, halt and power_off stubs. They just call _machine_restart,
247 * _machine_halt or _machine_power_off.
250 void machine_restart(char *command
)
252 if ((!in_interrupt() && !in_atomic()) || oops_in_progress
)
254 * Only unblank the console if we are called in enabled
255 * context or a bust_spinlocks cleared the way for us.
258 _machine_restart(command
);
261 void machine_halt(void)
263 if (!in_interrupt() || oops_in_progress
)
265 * Only unblank the console if we are called in enabled
266 * context or a bust_spinlocks cleared the way for us.
272 void machine_power_off(void)
274 if (!in_interrupt() || oops_in_progress
)
276 * Only unblank the console if we are called in enabled
277 * context or a bust_spinlocks cleared the way for us.
280 _machine_power_off();
284 * Dummy power off function.
286 void (*pm_power_off
)(void) = machine_power_off
;
287 EXPORT_SYMBOL_GPL(pm_power_off
);
289 static int __init
parse_vmalloc(char *arg
)
293 VMALLOC_END
= (memparse(arg
, &arg
) + PAGE_SIZE
- 1) & PAGE_MASK
;
296 early_param("vmalloc", parse_vmalloc
);
298 void *restart_stack
__section(.data
);
300 unsigned long stack_alloc(void)
302 #ifdef CONFIG_VMAP_STACK
303 return (unsigned long)
304 __vmalloc_node_range(THREAD_SIZE
, THREAD_SIZE
,
305 VMALLOC_START
, VMALLOC_END
,
307 PAGE_KERNEL
, 0, NUMA_NO_NODE
,
308 __builtin_return_address(0));
310 return __get_free_pages(GFP_KERNEL
, THREAD_SIZE_ORDER
);
314 void stack_free(unsigned long stack
)
316 #ifdef CONFIG_VMAP_STACK
317 vfree((void *) stack
);
319 free_pages(stack
, THREAD_SIZE_ORDER
);
323 int __init
arch_early_irq_init(void)
327 stack
= __get_free_pages(GFP_KERNEL
, THREAD_SIZE_ORDER
);
329 panic("Couldn't allocate async stack");
330 S390_lowcore
.async_stack
= stack
+ STACK_INIT_OFFSET
;
334 static int __init
async_stack_realloc(void)
336 unsigned long old
, new;
338 old
= S390_lowcore
.async_stack
- STACK_INIT_OFFSET
;
341 panic("Couldn't allocate async stack");
342 S390_lowcore
.async_stack
= new + STACK_INIT_OFFSET
;
343 free_pages(old
, THREAD_SIZE_ORDER
);
346 early_initcall(async_stack_realloc
);
348 void __init
arch_call_rest_init(void)
350 struct stack_frame
*frame
;
353 stack
= stack_alloc();
355 panic("Couldn't allocate kernel stack");
356 current
->stack
= (void *) stack
;
357 #ifdef CONFIG_VMAP_STACK
358 current
->stack_vm_area
= (void *) stack
;
360 set_task_stack_end_magic(current
);
361 stack
+= STACK_INIT_OFFSET
;
362 S390_lowcore
.kernel_stack
= stack
;
363 frame
= (struct stack_frame
*) stack
;
364 memset(frame
, 0, sizeof(*frame
));
365 /* Branch to rest_init on the new stack, never returns */
367 " la 15,0(%[_frame])\n"
369 : : [_frame
] "a" (frame
));
372 static void __init
setup_lowcore(void)
377 * Setup lowcore for boot cpu
379 BUILD_BUG_ON(sizeof(struct lowcore
) != LC_PAGES
* PAGE_SIZE
);
380 lc
= memblock_alloc_low(sizeof(*lc
), sizeof(*lc
));
381 lc
->restart_psw
.mask
= PSW_KERNEL_BITS
;
382 lc
->restart_psw
.addr
= (unsigned long) restart_int_handler
;
383 lc
->external_new_psw
.mask
= PSW_KERNEL_BITS
|
384 PSW_MASK_DAT
| PSW_MASK_MCHECK
;
385 lc
->external_new_psw
.addr
= (unsigned long) ext_int_handler
;
386 lc
->svc_new_psw
.mask
= PSW_KERNEL_BITS
|
387 PSW_MASK_DAT
| PSW_MASK_IO
| PSW_MASK_EXT
| PSW_MASK_MCHECK
;
388 lc
->svc_new_psw
.addr
= (unsigned long) system_call
;
389 lc
->program_new_psw
.mask
= PSW_KERNEL_BITS
|
390 PSW_MASK_DAT
| PSW_MASK_MCHECK
;
391 lc
->program_new_psw
.addr
= (unsigned long) pgm_check_handler
;
392 lc
->mcck_new_psw
.mask
= PSW_KERNEL_BITS
;
393 lc
->mcck_new_psw
.addr
= (unsigned long) mcck_int_handler
;
394 lc
->io_new_psw
.mask
= PSW_KERNEL_BITS
|
395 PSW_MASK_DAT
| PSW_MASK_MCHECK
;
396 lc
->io_new_psw
.addr
= (unsigned long) io_int_handler
;
397 lc
->clock_comparator
= clock_comparator_max
;
398 lc
->nodat_stack
= ((unsigned long) &init_thread_union
)
399 + THREAD_SIZE
- STACK_FRAME_OVERHEAD
- sizeof(struct pt_regs
);
400 lc
->current_task
= (unsigned long)&init_task
;
402 lc
->machine_flags
= S390_lowcore
.machine_flags
;
403 lc
->preempt_count
= S390_lowcore
.preempt_count
;
404 lc
->stfl_fac_list
= S390_lowcore
.stfl_fac_list
;
405 memcpy(lc
->stfle_fac_list
, S390_lowcore
.stfle_fac_list
,
406 sizeof(lc
->stfle_fac_list
));
407 memcpy(lc
->alt_stfle_fac_list
, S390_lowcore
.alt_stfle_fac_list
,
408 sizeof(lc
->alt_stfle_fac_list
));
409 nmi_alloc_boot_cpu(lc
);
410 vdso_alloc_boot_cpu(lc
);
411 lc
->sync_enter_timer
= S390_lowcore
.sync_enter_timer
;
412 lc
->async_enter_timer
= S390_lowcore
.async_enter_timer
;
413 lc
->exit_timer
= S390_lowcore
.exit_timer
;
414 lc
->user_timer
= S390_lowcore
.user_timer
;
415 lc
->system_timer
= S390_lowcore
.system_timer
;
416 lc
->steal_timer
= S390_lowcore
.steal_timer
;
417 lc
->last_update_timer
= S390_lowcore
.last_update_timer
;
418 lc
->last_update_clock
= S390_lowcore
.last_update_clock
;
421 * Allocate the global restart stack which is the same for
422 * all CPUs in cast *one* of them does a PSW restart.
424 restart_stack
= memblock_alloc(THREAD_SIZE
, THREAD_SIZE
);
425 restart_stack
+= STACK_INIT_OFFSET
;
428 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
429 * restart data to the absolute zero lowcore. This is necessary if
430 * PSW restart is done on an offline CPU that has lowcore zero.
432 lc
->restart_stack
= (unsigned long) restart_stack
;
433 lc
->restart_fn
= (unsigned long) do_restart
;
434 lc
->restart_data
= 0;
435 lc
->restart_source
= -1UL;
437 /* Setup absolute zero lowcore */
438 mem_assign_absolute(S390_lowcore
.restart_stack
, lc
->restart_stack
);
439 mem_assign_absolute(S390_lowcore
.restart_fn
, lc
->restart_fn
);
440 mem_assign_absolute(S390_lowcore
.restart_data
, lc
->restart_data
);
441 mem_assign_absolute(S390_lowcore
.restart_source
, lc
->restart_source
);
442 mem_assign_absolute(S390_lowcore
.restart_psw
, lc
->restart_psw
);
445 lc
->spinlock_lockval
= arch_spin_lockval(0);
446 lc
->spinlock_index
= 0;
447 arch_spin_lock_setup(0);
449 lc
->br_r1_trampoline
= 0x07f1; /* br %r1 */
451 set_prefix((u32
)(unsigned long) lc
);
455 static struct resource code_resource
= {
456 .name
= "Kernel code",
457 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
460 static struct resource data_resource
= {
461 .name
= "Kernel data",
462 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
465 static struct resource bss_resource
= {
466 .name
= "Kernel bss",
467 .flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
,
470 static struct resource __initdata
*standard_resources
[] = {
476 static void __init
setup_resources(void)
478 struct resource
*res
, *std_res
, *sub_res
;
479 struct memblock_region
*reg
;
482 code_resource
.start
= (unsigned long) _text
;
483 code_resource
.end
= (unsigned long) _etext
- 1;
484 data_resource
.start
= (unsigned long) _etext
;
485 data_resource
.end
= (unsigned long) _edata
- 1;
486 bss_resource
.start
= (unsigned long) __bss_start
;
487 bss_resource
.end
= (unsigned long) __bss_stop
- 1;
489 for_each_memblock(memory
, reg
) {
490 res
= memblock_alloc(sizeof(*res
), 8);
491 res
->flags
= IORESOURCE_BUSY
| IORESOURCE_SYSTEM_RAM
;
493 res
->name
= "System RAM";
494 res
->start
= reg
->base
;
495 res
->end
= reg
->base
+ reg
->size
- 1;
496 request_resource(&iomem_resource
, res
);
498 for (j
= 0; j
< ARRAY_SIZE(standard_resources
); j
++) {
499 std_res
= standard_resources
[j
];
500 if (std_res
->start
< res
->start
||
501 std_res
->start
> res
->end
)
503 if (std_res
->end
> res
->end
) {
504 sub_res
= memblock_alloc(sizeof(*sub_res
), 8);
506 sub_res
->end
= res
->end
;
507 std_res
->start
= res
->end
+ 1;
508 request_resource(res
, sub_res
);
510 request_resource(res
, std_res
);
514 #ifdef CONFIG_CRASH_DUMP
516 * Re-add removed crash kernel memory as reserved memory. This makes
517 * sure it will be mapped with the identity mapping and struct pages
518 * will be created, so it can be resized later on.
519 * However add it later since the crash kernel resource should not be
520 * part of the System RAM resource.
522 if (crashk_res
.end
) {
523 memblock_add_node(crashk_res
.start
, resource_size(&crashk_res
), 0);
524 memblock_reserve(crashk_res
.start
, resource_size(&crashk_res
));
525 insert_resource(&iomem_resource
, &crashk_res
);
530 static void __init
setup_memory_end(void)
532 unsigned long vmax
, vmalloc_size
, tmp
;
534 /* Choose kernel address space layout: 3 or 4 levels. */
535 vmalloc_size
= VMALLOC_END
?: (128UL << 30) - MODULES_LEN
;
536 if (IS_ENABLED(CONFIG_KASAN
)) {
537 vmax
= IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING
)
541 tmp
= (memory_end
?: max_physmem_end
) / PAGE_SIZE
;
542 tmp
= tmp
* (sizeof(struct page
) + PAGE_SIZE
);
543 if (tmp
+ vmalloc_size
+ MODULES_LEN
<= _REGION2_SIZE
)
544 vmax
= _REGION2_SIZE
; /* 3-level kernel page table */
546 vmax
= _REGION1_SIZE
; /* 4-level kernel page table */
549 /* module area is at the end of the kernel address space. */
551 MODULES_VADDR
= MODULES_END
- MODULES_LEN
;
552 VMALLOC_END
= MODULES_VADDR
;
553 VMALLOC_START
= VMALLOC_END
- vmalloc_size
;
555 /* Split remaining virtual space between 1:1 mapping & vmemmap array */
556 tmp
= VMALLOC_START
/ (PAGE_SIZE
+ sizeof(struct page
));
557 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
558 tmp
= SECTION_ALIGN_UP(tmp
);
559 tmp
= VMALLOC_START
- tmp
* sizeof(struct page
);
560 tmp
&= ~((vmax
>> 11) - 1); /* align to page table level */
561 tmp
= min(tmp
, 1UL << MAX_PHYSMEM_BITS
);
562 vmemmap
= (struct page
*) tmp
;
564 /* Take care that memory_end is set and <= vmemmap */
565 memory_end
= min(memory_end
?: max_physmem_end
, (unsigned long)vmemmap
);
567 /* fit in kasan shadow memory region between 1:1 and vmemmap */
568 memory_end
= min(memory_end
, KASAN_SHADOW_START
);
569 vmemmap
= max(vmemmap
, (struct page
*)KASAN_SHADOW_END
);
571 max_pfn
= max_low_pfn
= PFN_DOWN(memory_end
);
572 memblock_remove(memory_end
, ULONG_MAX
);
574 pr_notice("The maximum memory size is %luMB\n", memory_end
>> 20);
577 #ifdef CONFIG_CRASH_DUMP
580 * When kdump is enabled, we have to ensure that no memory from
581 * the area [0 - crashkernel memory size] and
582 * [crashk_res.start - crashk_res.end] is set offline.
584 static int kdump_mem_notifier(struct notifier_block
*nb
,
585 unsigned long action
, void *data
)
587 struct memory_notify
*arg
= data
;
589 if (action
!= MEM_GOING_OFFLINE
)
591 if (arg
->start_pfn
< PFN_DOWN(resource_size(&crashk_res
)))
593 if (arg
->start_pfn
> PFN_DOWN(crashk_res
.end
))
595 if (arg
->start_pfn
+ arg
->nr_pages
- 1 < PFN_DOWN(crashk_res
.start
))
600 static struct notifier_block kdump_mem_nb
= {
601 .notifier_call
= kdump_mem_notifier
,
607 * Make sure that the area behind memory_end is protected
609 static void reserve_memory_end(void)
612 memblock_reserve(memory_end
, ULONG_MAX
);
616 * Make sure that oldmem, where the dump is stored, is protected
618 static void reserve_oldmem(void)
620 #ifdef CONFIG_CRASH_DUMP
622 /* Forget all memory above the running kdump system */
623 memblock_reserve(OLDMEM_SIZE
, (phys_addr_t
)ULONG_MAX
);
628 * Make sure that oldmem, where the dump is stored, is protected
630 static void remove_oldmem(void)
632 #ifdef CONFIG_CRASH_DUMP
634 /* Forget all memory above the running kdump system */
635 memblock_remove(OLDMEM_SIZE
, (phys_addr_t
)ULONG_MAX
);
640 * Reserve memory for kdump kernel to be loaded with kexec
642 static void __init
reserve_crashkernel(void)
644 #ifdef CONFIG_CRASH_DUMP
645 unsigned long long crash_base
, crash_size
;
646 phys_addr_t low
, high
;
649 rc
= parse_crashkernel(boot_command_line
, memory_end
, &crash_size
,
652 crash_base
= ALIGN(crash_base
, KEXEC_CRASH_MEM_ALIGN
);
653 crash_size
= ALIGN(crash_size
, KEXEC_CRASH_MEM_ALIGN
);
654 if (rc
|| crash_size
== 0)
657 if (memblock
.memory
.regions
[0].size
< crash_size
) {
658 pr_info("crashkernel reservation failed: %s\n",
659 "first memory chunk must be at least crashkernel size");
663 low
= crash_base
?: OLDMEM_BASE
;
664 high
= low
+ crash_size
;
665 if (low
>= OLDMEM_BASE
&& high
<= OLDMEM_BASE
+ OLDMEM_SIZE
) {
666 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
669 /* Find suitable area in free memory */
670 low
= max_t(unsigned long, crash_size
, sclp
.hsa_size
);
671 high
= crash_base
? crash_base
+ crash_size
: ULONG_MAX
;
673 if (crash_base
&& crash_base
< low
) {
674 pr_info("crashkernel reservation failed: %s\n",
675 "crash_base too low");
678 low
= crash_base
?: low
;
679 crash_base
= memblock_find_in_range(low
, high
, crash_size
,
680 KEXEC_CRASH_MEM_ALIGN
);
684 pr_info("crashkernel reservation failed: %s\n",
685 "no suitable area found");
689 if (register_memory_notifier(&kdump_mem_nb
))
692 if (!OLDMEM_BASE
&& MACHINE_IS_VM
)
693 diag10_range(PFN_DOWN(crash_base
), PFN_DOWN(crash_size
));
694 crashk_res
.start
= crash_base
;
695 crashk_res
.end
= crash_base
+ crash_size
- 1;
696 memblock_remove(crash_base
, crash_size
);
697 pr_info("Reserving %lluMB of memory at %lluMB "
698 "for crashkernel (System RAM: %luMB)\n",
699 crash_size
>> 20, crash_base
>> 20,
700 (unsigned long)memblock
.memory
.total_size
>> 20);
701 os_info_crashkernel_add(crash_base
, crash_size
);
706 * Reserve the initrd from being used by memblock
708 static void __init
reserve_initrd(void)
710 #ifdef CONFIG_BLK_DEV_INITRD
711 if (!INITRD_START
|| !INITRD_SIZE
)
713 initrd_start
= INITRD_START
;
714 initrd_end
= initrd_start
+ INITRD_SIZE
;
715 memblock_reserve(INITRD_START
, INITRD_SIZE
);
719 static void __init
reserve_mem_detect_info(void)
721 unsigned long start
, size
;
723 get_mem_detect_reserved(&start
, &size
);
725 memblock_reserve(start
, size
);
728 static void __init
free_mem_detect_info(void)
730 unsigned long start
, size
;
732 get_mem_detect_reserved(&start
, &size
);
734 memblock_free(start
, size
);
737 static void __init
memblock_physmem_add(phys_addr_t start
, phys_addr_t size
)
739 memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
740 start
, start
+ size
- 1);
741 memblock_add_range(&memblock
.memory
, start
, size
, 0, 0);
742 memblock_add_range(&memblock
.physmem
, start
, size
, 0, 0);
745 static const char * __init
get_mem_info_source(void)
747 switch (mem_detect
.info_source
) {
748 case MEM_DETECT_SCLP_STOR_INFO
:
749 return "sclp storage info";
750 case MEM_DETECT_DIAG260
:
752 case MEM_DETECT_SCLP_READ_INFO
:
753 return "sclp read info";
754 case MEM_DETECT_BIN_SEARCH
:
755 return "binary search";
760 static void __init
memblock_add_mem_detect_info(void)
762 unsigned long start
, end
;
765 memblock_dbg("physmem info source: %s (%hhd)\n",
766 get_mem_info_source(), mem_detect
.info_source
);
767 /* keep memblock lists close to the kernel */
768 memblock_set_bottom_up(true);
769 for_each_mem_detect_block(i
, &start
, &end
)
770 memblock_physmem_add(start
, end
- start
);
771 memblock_set_bottom_up(false);
776 * Check for initrd being in usable memory
778 static void __init
check_initrd(void)
780 #ifdef CONFIG_BLK_DEV_INITRD
781 if (INITRD_START
&& INITRD_SIZE
&&
782 !memblock_is_region_memory(INITRD_START
, INITRD_SIZE
)) {
783 pr_err("The initial RAM disk does not fit into the memory\n");
784 memblock_free(INITRD_START
, INITRD_SIZE
);
785 initrd_start
= initrd_end
= 0;
791 * Reserve memory used for lowcore/command line/kernel image.
793 static void __init
reserve_kernel(void)
795 unsigned long start_pfn
= PFN_UP(__pa(_end
));
797 #ifdef CONFIG_DMA_API_DEBUG
799 * DMA_API_DEBUG code stumbles over addresses from the
800 * range [PARMAREA_END, _stext]. Mark the memory as reserved
801 * so it is not used for CONFIG_DMA_API_DEBUG=y.
803 memblock_reserve(0, PFN_PHYS(start_pfn
));
805 memblock_reserve(0, PARMAREA_END
);
806 memblock_reserve((unsigned long)_stext
, PFN_PHYS(start_pfn
)
807 - (unsigned long)_stext
);
811 static void __init
setup_memory(void)
813 struct memblock_region
*reg
;
816 * Init storage key for present memory
818 for_each_memblock(memory
, reg
) {
819 storage_key_init_range(reg
->base
, reg
->base
+ reg
->size
);
821 psw_set_key(PAGE_DEFAULT_KEY
);
824 memblock_enforce_memory_limit(memblock_end_of_DRAM());
828 * Setup hardware capabilities.
830 static int __init
setup_hwcaps(void)
832 static const int stfl_bits
[6] = { 0, 2, 7, 17, 19, 21 };
837 * The store facility list bits numbers as found in the principles
838 * of operation are numbered with bit 1UL<<31 as number 0 to
839 * bit 1UL<<0 as number 31.
840 * Bit 0: instructions named N3, "backported" to esa-mode
841 * Bit 2: z/Architecture mode is active
842 * Bit 7: the store-facility-list-extended facility is installed
843 * Bit 17: the message-security assist is installed
844 * Bit 19: the long-displacement facility is installed
845 * Bit 21: the extended-immediate facility is installed
846 * Bit 22: extended-translation facility 3 is installed
847 * Bit 30: extended-translation facility 3 enhancement facility
848 * These get translated to:
849 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
850 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
851 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
852 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
854 for (i
= 0; i
< 6; i
++)
855 if (test_facility(stfl_bits
[i
]))
856 elf_hwcap
|= 1UL << i
;
858 if (test_facility(22) && test_facility(30))
859 elf_hwcap
|= HWCAP_S390_ETF3EH
;
862 * Check for additional facilities with store-facility-list-extended.
863 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
864 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
865 * as stored by stfl, bits 32-xxx contain additional facilities.
866 * How many facility words are stored depends on the number of
867 * doublewords passed to the instruction. The additional facilities
869 * Bit 42: decimal floating point facility is installed
870 * Bit 44: perform floating point operation facility is installed
872 * HWCAP_S390_DFP bit 6 (42 && 44).
874 if ((elf_hwcap
& (1UL << 2)) && test_facility(42) && test_facility(44))
875 elf_hwcap
|= HWCAP_S390_DFP
;
878 * Huge page support HWCAP_S390_HPAGE is bit 7.
880 if (MACHINE_HAS_EDAT1
)
881 elf_hwcap
|= HWCAP_S390_HPAGE
;
884 * 64-bit register support for 31-bit processes
885 * HWCAP_S390_HIGH_GPRS is bit 9.
887 elf_hwcap
|= HWCAP_S390_HIGH_GPRS
;
890 * Transactional execution support HWCAP_S390_TE is bit 10.
893 elf_hwcap
|= HWCAP_S390_TE
;
896 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
897 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
898 * instead of facility bit 129.
900 if (MACHINE_HAS_VX
) {
901 elf_hwcap
|= HWCAP_S390_VXRS
;
902 if (test_facility(134))
903 elf_hwcap
|= HWCAP_S390_VXRS_EXT
;
904 if (test_facility(135))
905 elf_hwcap
|= HWCAP_S390_VXRS_BCD
;
909 * Guarded storage support HWCAP_S390_GS is bit 12.
912 elf_hwcap
|= HWCAP_S390_GS
;
915 add_device_randomness(&cpu_id
, sizeof(cpu_id
));
916 switch (cpu_id
.machine
) {
919 default: /* Use "z900" as default for 64 bit kernels. */
920 strcpy(elf_platform
, "z900");
924 strcpy(elf_platform
, "z990");
928 strcpy(elf_platform
, "z9-109");
932 strcpy(elf_platform
, "z10");
936 strcpy(elf_platform
, "z196");
940 strcpy(elf_platform
, "zEC12");
944 strcpy(elf_platform
, "z13");
948 strcpy(elf_platform
, "z14");
953 * Virtualization support HWCAP_INT_SIE is bit 0.
956 int_hwcap
|= HWCAP_INT_SIE
;
960 arch_initcall(setup_hwcaps
);
963 * Add system information as device randomness
965 static void __init
setup_randomness(void)
967 struct sysinfo_3_2_2
*vmms
;
969 vmms
= (struct sysinfo_3_2_2
*) memblock_phys_alloc(PAGE_SIZE
,
971 if (stsi(vmms
, 3, 2, 2) == 0 && vmms
->count
)
972 add_device_randomness(&vmms
->vm
, sizeof(vmms
->vm
[0]) * vmms
->count
);
973 memblock_free((unsigned long) vmms
, PAGE_SIZE
);
977 * Find the correct size for the task_struct. This depends on
978 * the size of the struct fpu at the end of the thread_struct
979 * which is embedded in the task_struct.
981 static void __init
setup_task_size(void)
983 int task_size
= sizeof(struct task_struct
);
985 if (!MACHINE_HAS_VX
) {
986 task_size
-= sizeof(__vector128
) * __NUM_VXRS
;
987 task_size
+= sizeof(freg_t
) * __NUM_FPRS
;
989 arch_task_struct_size
= task_size
;
993 * Setup function called from init/main.c just after the banner
997 void __init
setup_arch(char **cmdline_p
)
1000 * print what head.S has found out about the machine
1003 pr_info("Linux is running as a z/VM "
1004 "guest operating system in 64-bit mode\n");
1005 else if (MACHINE_IS_KVM
)
1006 pr_info("Linux is running under KVM in 64-bit mode\n");
1007 else if (MACHINE_IS_LPAR
)
1008 pr_info("Linux is running natively in 64-bit mode\n");
1010 /* Have one command line that is parsed and saved in /proc/cmdline */
1011 /* boot_command_line has been already set up in early.c */
1012 *cmdline_p
= boot_command_line
;
1014 ROOT_DEV
= Root_RAM0
;
1016 /* Is init_mm really needed? */
1017 init_mm
.start_code
= PAGE_OFFSET
;
1018 init_mm
.end_code
= (unsigned long) _etext
;
1019 init_mm
.end_data
= (unsigned long) _edata
;
1020 init_mm
.brk
= (unsigned long) _end
;
1022 if (IS_ENABLED(CONFIG_EXPOLINE_AUTO
))
1023 nospec_auto_detect();
1025 parse_early_param();
1026 #ifdef CONFIG_CRASH_DUMP
1027 /* Deactivate elfcorehdr= kernel parameter */
1028 elfcorehdr_addr
= ELFCORE_ADDR_MAX
;
1035 /* Do some memory reservations *before* memory is added to memblock */
1036 reserve_memory_end();
1040 reserve_mem_detect_info();
1041 memblock_allow_resize();
1043 /* Get information about *all* installed memory */
1044 memblock_add_mem_detect_info();
1046 free_mem_detect_info();
1050 * Make sure all chunks are MAX_ORDER aligned so we don't need the
1051 * extra checks that HOLES_IN_ZONE would require.
1053 * Is this still required?
1055 memblock_trim_memory(1UL << (MAX_ORDER
- 1 + PAGE_SHIFT
));
1059 dma_contiguous_reserve(memory_end
);
1063 reserve_crashkernel();
1064 #ifdef CONFIG_CRASH_DUMP
1066 * Be aware that smp_save_dump_cpus() triggers a system reset.
1067 * Therefore CPU and device initialization should be done afterwards.
1069 smp_save_dump_cpus();
1074 smp_fill_possible_mask();
1075 cpu_detect_mhz_feature();
1079 topology_init_early();
1082 * Create kernel page tables and switch to virtual addressing.
1086 /* Setup default console */
1088 set_preferred_console();
1090 apply_alternative_instructions();
1091 if (IS_ENABLED(CONFIG_EXPOLINE
))
1092 nospec_init_branches();
1094 /* Setup zfcpdump support */
1097 /* Add system specific data to the random pool */