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[linux/fpc-iii.git] / arch / s390 / kernel / setup.c
blob3d1d808ea8a97bb31be7dee6a7c06e16b3f56ad6
1 /*
2 * S390 version
3 * Copyright IBM Corp. 1999, 2012
4 * Author(s): Hartmut Penner (hp@de.ibm.com),
5 * Martin Schwidefsky (schwidefsky@de.ibm.com)
7 * Derived from "arch/i386/kernel/setup.c"
8 * Copyright (C) 1995, Linus Torvalds
9 */
12 * This file handles the architecture-dependent parts of initialization
15 #define KMSG_COMPONENT "setup"
16 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
18 #include <linux/errno.h>
19 #include <linux/export.h>
20 #include <linux/sched.h>
21 #include <linux/sched/task.h>
22 #include <linux/cpu.h>
23 #include <linux/kernel.h>
24 #include <linux/memblock.h>
25 #include <linux/mm.h>
26 #include <linux/stddef.h>
27 #include <linux/unistd.h>
28 #include <linux/ptrace.h>
29 #include <linux/random.h>
30 #include <linux/user.h>
31 #include <linux/tty.h>
32 #include <linux/ioport.h>
33 #include <linux/delay.h>
34 #include <linux/init.h>
35 #include <linux/initrd.h>
36 #include <linux/bootmem.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>
52 #include <asm/ipl.h>
53 #include <asm/facility.h>
54 #include <asm/smp.h>
55 #include <asm/mmu_context.h>
56 #include <asm/cpcmd.h>
57 #include <asm/lowcore.h>
58 #include <asm/irq.h>
59 #include <asm/page.h>
60 #include <asm/ptrace.h>
61 #include <asm/sections.h>
62 #include <asm/ebcdic.h>
63 #include <asm/kvm_virtio.h>
64 #include <asm/diag.h>
65 #include <asm/os_info.h>
66 #include <asm/sclp.h>
67 #include <asm/sysinfo.h>
68 #include <asm/numa.h>
69 #include "entry.h"
72 * Machine setup..
74 unsigned int console_mode = 0;
75 EXPORT_SYMBOL(console_mode);
77 unsigned int console_devno = -1;
78 EXPORT_SYMBOL(console_devno);
80 unsigned int console_irq = -1;
81 EXPORT_SYMBOL(console_irq);
83 unsigned long elf_hwcap __read_mostly = 0;
84 char elf_platform[ELF_PLATFORM_SIZE];
86 unsigned long int_hwcap = 0;
88 int __initdata memory_end_set;
89 unsigned long __initdata memory_end;
90 unsigned long __initdata max_physmem_end;
92 unsigned long VMALLOC_START;
93 EXPORT_SYMBOL(VMALLOC_START);
95 unsigned long VMALLOC_END;
96 EXPORT_SYMBOL(VMALLOC_END);
98 struct page *vmemmap;
99 EXPORT_SYMBOL(vmemmap);
101 unsigned long MODULES_VADDR;
102 unsigned long MODULES_END;
104 /* An array with a pointer to the lowcore of every CPU. */
105 struct lowcore *lowcore_ptr[NR_CPUS];
106 EXPORT_SYMBOL(lowcore_ptr);
109 * This is set up by the setup-routine at boot-time
110 * for S390 need to find out, what we have to setup
111 * using address 0x10400 ...
114 #include <asm/setup.h>
117 * condev= and conmode= setup parameter.
120 static int __init condev_setup(char *str)
122 int vdev;
124 vdev = simple_strtoul(str, &str, 0);
125 if (vdev >= 0 && vdev < 65536) {
126 console_devno = vdev;
127 console_irq = -1;
129 return 1;
132 __setup("condev=", condev_setup);
134 static void __init set_preferred_console(void)
136 if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
137 add_preferred_console("ttyS", 0, NULL);
138 else if (CONSOLE_IS_3270)
139 add_preferred_console("tty3270", 0, NULL);
140 else if (CONSOLE_IS_VT220)
141 add_preferred_console("ttyS", 1, NULL);
142 else if (CONSOLE_IS_HVC)
143 add_preferred_console("hvc", 0, NULL);
146 static int __init conmode_setup(char *str)
148 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
149 if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
150 SET_CONSOLE_SCLP;
151 #endif
152 #if defined(CONFIG_TN3215_CONSOLE)
153 if (strncmp(str, "3215", 5) == 0)
154 SET_CONSOLE_3215;
155 #endif
156 #if defined(CONFIG_TN3270_CONSOLE)
157 if (strncmp(str, "3270", 5) == 0)
158 SET_CONSOLE_3270;
159 #endif
160 set_preferred_console();
161 return 1;
164 __setup("conmode=", conmode_setup);
166 static void __init conmode_default(void)
168 char query_buffer[1024];
169 char *ptr;
171 if (MACHINE_IS_VM) {
172 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
173 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
174 ptr = strstr(query_buffer, "SUBCHANNEL =");
175 console_irq = simple_strtoul(ptr + 13, NULL, 16);
176 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
177 ptr = strstr(query_buffer, "CONMODE");
179 * Set the conmode to 3215 so that the device recognition
180 * will set the cu_type of the console to 3215. If the
181 * conmode is 3270 and we don't set it back then both
182 * 3215 and the 3270 driver will try to access the console
183 * device (3215 as console and 3270 as normal tty).
185 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
186 if (ptr == NULL) {
187 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
188 SET_CONSOLE_SCLP;
189 #endif
190 return;
192 if (strncmp(ptr + 8, "3270", 4) == 0) {
193 #if defined(CONFIG_TN3270_CONSOLE)
194 SET_CONSOLE_3270;
195 #elif defined(CONFIG_TN3215_CONSOLE)
196 SET_CONSOLE_3215;
197 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
198 SET_CONSOLE_SCLP;
199 #endif
200 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
201 #if defined(CONFIG_TN3215_CONSOLE)
202 SET_CONSOLE_3215;
203 #elif defined(CONFIG_TN3270_CONSOLE)
204 SET_CONSOLE_3270;
205 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
206 SET_CONSOLE_SCLP;
207 #endif
209 } else if (MACHINE_IS_KVM) {
210 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
211 SET_CONSOLE_VT220;
212 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
213 SET_CONSOLE_SCLP;
214 else
215 SET_CONSOLE_HVC;
216 } else {
217 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
218 SET_CONSOLE_SCLP;
219 #endif
223 #ifdef CONFIG_CRASH_DUMP
224 static void __init setup_zfcpdump(void)
226 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
227 return;
228 if (OLDMEM_BASE)
229 return;
230 strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
231 console_loglevel = 2;
233 #else
234 static inline void setup_zfcpdump(void) {}
235 #endif /* CONFIG_CRASH_DUMP */
238 * Reboot, halt and power_off stubs. They just call _machine_restart,
239 * _machine_halt or _machine_power_off.
242 void machine_restart(char *command)
244 if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
246 * Only unblank the console if we are called in enabled
247 * context or a bust_spinlocks cleared the way for us.
249 console_unblank();
250 _machine_restart(command);
253 void machine_halt(void)
255 if (!in_interrupt() || oops_in_progress)
257 * Only unblank the console if we are called in enabled
258 * context or a bust_spinlocks cleared the way for us.
260 console_unblank();
261 _machine_halt();
264 void machine_power_off(void)
266 if (!in_interrupt() || oops_in_progress)
268 * Only unblank the console if we are called in enabled
269 * context or a bust_spinlocks cleared the way for us.
271 console_unblank();
272 _machine_power_off();
276 * Dummy power off function.
278 void (*pm_power_off)(void) = machine_power_off;
279 EXPORT_SYMBOL_GPL(pm_power_off);
281 static int __init early_parse_mem(char *p)
283 memory_end = memparse(p, &p);
284 memory_end &= PAGE_MASK;
285 memory_end_set = 1;
286 return 0;
288 early_param("mem", early_parse_mem);
290 static int __init parse_vmalloc(char *arg)
292 if (!arg)
293 return -EINVAL;
294 VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
295 return 0;
297 early_param("vmalloc", parse_vmalloc);
299 void *restart_stack __section(.data);
301 static void __init setup_lowcore(void)
303 struct lowcore *lc;
306 * Setup lowcore for boot cpu
308 BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * 4096);
309 lc = memblock_virt_alloc_low(sizeof(*lc), sizeof(*lc));
310 lc->restart_psw.mask = PSW_KERNEL_BITS;
311 lc->restart_psw.addr = (unsigned long) restart_int_handler;
312 lc->external_new_psw.mask = PSW_KERNEL_BITS |
313 PSW_MASK_DAT | PSW_MASK_MCHECK;
314 lc->external_new_psw.addr = (unsigned long) ext_int_handler;
315 lc->svc_new_psw.mask = PSW_KERNEL_BITS |
316 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
317 lc->svc_new_psw.addr = (unsigned long) system_call;
318 lc->program_new_psw.mask = PSW_KERNEL_BITS |
319 PSW_MASK_DAT | PSW_MASK_MCHECK;
320 lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
321 lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
322 lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
323 lc->io_new_psw.mask = PSW_KERNEL_BITS |
324 PSW_MASK_DAT | PSW_MASK_MCHECK;
325 lc->io_new_psw.addr = (unsigned long) io_int_handler;
326 lc->clock_comparator = -1ULL;
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;
336 lc->lpp = LPP_MAGIC;
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 MAX_FACILITY_BIT/8);
342 if (MACHINE_HAS_VX || MACHINE_HAS_GS) {
343 unsigned long bits, size;
345 bits = MACHINE_HAS_GS ? 11 : 10;
346 size = 1UL << bits;
347 lc->mcesad = (__u64) memblock_virt_alloc(size, size);
348 if (MACHINE_HAS_GS)
349 lc->mcesad |= bits;
351 lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
352 lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
353 lc->async_enter_timer = S390_lowcore.async_enter_timer;
354 lc->exit_timer = S390_lowcore.exit_timer;
355 lc->user_timer = S390_lowcore.user_timer;
356 lc->system_timer = S390_lowcore.system_timer;
357 lc->steal_timer = S390_lowcore.steal_timer;
358 lc->last_update_timer = S390_lowcore.last_update_timer;
359 lc->last_update_clock = S390_lowcore.last_update_clock;
361 restart_stack = memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE);
362 restart_stack += ASYNC_SIZE;
365 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
366 * restart data to the absolute zero lowcore. This is necessary if
367 * PSW restart is done on an offline CPU that has lowcore zero.
369 lc->restart_stack = (unsigned long) restart_stack;
370 lc->restart_fn = (unsigned long) do_restart;
371 lc->restart_data = 0;
372 lc->restart_source = -1UL;
374 /* Setup absolute zero lowcore */
375 mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
376 mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
377 mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
378 mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
379 mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
381 #ifdef CONFIG_SMP
382 lc->spinlock_lockval = arch_spin_lockval(0);
383 #endif
385 set_prefix((u32)(unsigned long) lc);
386 lowcore_ptr[0] = lc;
389 static struct resource code_resource = {
390 .name = "Kernel code",
391 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
394 static struct resource data_resource = {
395 .name = "Kernel data",
396 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
399 static struct resource bss_resource = {
400 .name = "Kernel bss",
401 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
404 static struct resource __initdata *standard_resources[] = {
405 &code_resource,
406 &data_resource,
407 &bss_resource,
410 static void __init setup_resources(void)
412 struct resource *res, *std_res, *sub_res;
413 struct memblock_region *reg;
414 int j;
416 code_resource.start = (unsigned long) &_text;
417 code_resource.end = (unsigned long) &_etext - 1;
418 data_resource.start = (unsigned long) &_etext;
419 data_resource.end = (unsigned long) &_edata - 1;
420 bss_resource.start = (unsigned long) &__bss_start;
421 bss_resource.end = (unsigned long) &__bss_stop - 1;
423 for_each_memblock(memory, reg) {
424 res = memblock_virt_alloc(sizeof(*res), 8);
425 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
427 res->name = "System RAM";
428 res->start = reg->base;
429 res->end = reg->base + reg->size - 1;
430 request_resource(&iomem_resource, res);
432 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
433 std_res = standard_resources[j];
434 if (std_res->start < res->start ||
435 std_res->start > res->end)
436 continue;
437 if (std_res->end > res->end) {
438 sub_res = memblock_virt_alloc(sizeof(*sub_res), 8);
439 *sub_res = *std_res;
440 sub_res->end = res->end;
441 std_res->start = res->end + 1;
442 request_resource(res, sub_res);
443 } else {
444 request_resource(res, std_res);
448 #ifdef CONFIG_CRASH_DUMP
450 * Re-add removed crash kernel memory as reserved memory. This makes
451 * sure it will be mapped with the identity mapping and struct pages
452 * will be created, so it can be resized later on.
453 * However add it later since the crash kernel resource should not be
454 * part of the System RAM resource.
456 if (crashk_res.end) {
457 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
458 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
459 insert_resource(&iomem_resource, &crashk_res);
461 #endif
464 static void __init setup_memory_end(void)
466 unsigned long vmax, vmalloc_size, tmp;
468 /* Choose kernel address space layout: 2, 3, or 4 levels. */
469 vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
470 tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
471 tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
472 if (tmp + vmalloc_size + MODULES_LEN <= (1UL << 42))
473 vmax = 1UL << 42; /* 3-level kernel page table */
474 else
475 vmax = 1UL << 53; /* 4-level kernel page table */
476 /* module area is at the end of the kernel address space. */
477 MODULES_END = vmax;
478 MODULES_VADDR = MODULES_END - MODULES_LEN;
479 VMALLOC_END = MODULES_VADDR;
480 VMALLOC_START = vmax - vmalloc_size;
482 /* Split remaining virtual space between 1:1 mapping & vmemmap array */
483 tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
484 /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
485 tmp = SECTION_ALIGN_UP(tmp);
486 tmp = VMALLOC_START - tmp * sizeof(struct page);
487 tmp &= ~((vmax >> 11) - 1); /* align to page table level */
488 tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
489 vmemmap = (struct page *) tmp;
491 /* Take care that memory_end is set and <= vmemmap */
492 memory_end = min(memory_end ?: max_physmem_end, tmp);
493 max_pfn = max_low_pfn = PFN_DOWN(memory_end);
494 memblock_remove(memory_end, ULONG_MAX);
496 pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
499 #ifdef CONFIG_CRASH_DUMP
502 * When kdump is enabled, we have to ensure that no memory from
503 * the area [0 - crashkernel memory size] and
504 * [crashk_res.start - crashk_res.end] is set offline.
506 static int kdump_mem_notifier(struct notifier_block *nb,
507 unsigned long action, void *data)
509 struct memory_notify *arg = data;
511 if (action != MEM_GOING_OFFLINE)
512 return NOTIFY_OK;
513 if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
514 return NOTIFY_BAD;
515 if (arg->start_pfn > PFN_DOWN(crashk_res.end))
516 return NOTIFY_OK;
517 if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
518 return NOTIFY_OK;
519 return NOTIFY_BAD;
522 static struct notifier_block kdump_mem_nb = {
523 .notifier_call = kdump_mem_notifier,
526 #endif
529 * Make sure that the area behind memory_end is protected
531 static void reserve_memory_end(void)
533 #ifdef CONFIG_CRASH_DUMP
534 if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
535 !OLDMEM_BASE && sclp.hsa_size) {
536 memory_end = sclp.hsa_size;
537 memory_end &= PAGE_MASK;
538 memory_end_set = 1;
540 #endif
541 if (!memory_end_set)
542 return;
543 memblock_reserve(memory_end, ULONG_MAX);
547 * Make sure that oldmem, where the dump is stored, is protected
549 static void reserve_oldmem(void)
551 #ifdef CONFIG_CRASH_DUMP
552 if (OLDMEM_BASE)
553 /* Forget all memory above the running kdump system */
554 memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
555 #endif
559 * Make sure that oldmem, where the dump is stored, is protected
561 static void remove_oldmem(void)
563 #ifdef CONFIG_CRASH_DUMP
564 if (OLDMEM_BASE)
565 /* Forget all memory above the running kdump system */
566 memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
567 #endif
571 * Reserve memory for kdump kernel to be loaded with kexec
573 static void __init reserve_crashkernel(void)
575 #ifdef CONFIG_CRASH_DUMP
576 unsigned long long crash_base, crash_size;
577 phys_addr_t low, high;
578 int rc;
580 rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
581 &crash_base);
583 crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
584 crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
585 if (rc || crash_size == 0)
586 return;
588 if (memblock.memory.regions[0].size < crash_size) {
589 pr_info("crashkernel reservation failed: %s\n",
590 "first memory chunk must be at least crashkernel size");
591 return;
594 low = crash_base ?: OLDMEM_BASE;
595 high = low + crash_size;
596 if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
597 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
598 crash_base = low;
599 } else {
600 /* Find suitable area in free memory */
601 low = max_t(unsigned long, crash_size, sclp.hsa_size);
602 high = crash_base ? crash_base + crash_size : ULONG_MAX;
604 if (crash_base && crash_base < low) {
605 pr_info("crashkernel reservation failed: %s\n",
606 "crash_base too low");
607 return;
609 low = crash_base ?: low;
610 crash_base = memblock_find_in_range(low, high, crash_size,
611 KEXEC_CRASH_MEM_ALIGN);
614 if (!crash_base) {
615 pr_info("crashkernel reservation failed: %s\n",
616 "no suitable area found");
617 return;
620 if (register_memory_notifier(&kdump_mem_nb))
621 return;
623 if (!OLDMEM_BASE && MACHINE_IS_VM)
624 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
625 crashk_res.start = crash_base;
626 crashk_res.end = crash_base + crash_size - 1;
627 memblock_remove(crash_base, crash_size);
628 pr_info("Reserving %lluMB of memory at %lluMB "
629 "for crashkernel (System RAM: %luMB)\n",
630 crash_size >> 20, crash_base >> 20,
631 (unsigned long)memblock.memory.total_size >> 20);
632 os_info_crashkernel_add(crash_base, crash_size);
633 #endif
637 * Reserve the initrd from being used by memblock
639 static void __init reserve_initrd(void)
641 #ifdef CONFIG_BLK_DEV_INITRD
642 if (!INITRD_START || !INITRD_SIZE)
643 return;
644 initrd_start = INITRD_START;
645 initrd_end = initrd_start + INITRD_SIZE;
646 memblock_reserve(INITRD_START, INITRD_SIZE);
647 #endif
651 * Check for initrd being in usable memory
653 static void __init check_initrd(void)
655 #ifdef CONFIG_BLK_DEV_INITRD
656 if (INITRD_START && INITRD_SIZE &&
657 !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
658 pr_err("The initial RAM disk does not fit into the memory\n");
659 memblock_free(INITRD_START, INITRD_SIZE);
660 initrd_start = initrd_end = 0;
662 #endif
666 * Reserve memory used for lowcore/command line/kernel image.
668 static void __init reserve_kernel(void)
670 unsigned long start_pfn = PFN_UP(__pa(&_end));
672 #ifdef CONFIG_DMA_API_DEBUG
674 * DMA_API_DEBUG code stumbles over addresses from the
675 * range [_ehead, _stext]. Mark the memory as reserved
676 * so it is not used for CONFIG_DMA_API_DEBUG=y.
678 memblock_reserve(0, PFN_PHYS(start_pfn));
679 #else
680 memblock_reserve(0, (unsigned long)_ehead);
681 memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
682 - (unsigned long)_stext);
683 #endif
686 static void __init setup_memory(void)
688 struct memblock_region *reg;
691 * Init storage key for present memory
693 for_each_memblock(memory, reg) {
694 storage_key_init_range(reg->base, reg->base + reg->size);
696 psw_set_key(PAGE_DEFAULT_KEY);
698 /* Only cosmetics */
699 memblock_enforce_memory_limit(memblock_end_of_DRAM());
703 * Setup hardware capabilities.
705 static int __init setup_hwcaps(void)
707 static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
708 struct cpuid cpu_id;
709 int i;
712 * The store facility list bits numbers as found in the principles
713 * of operation are numbered with bit 1UL<<31 as number 0 to
714 * bit 1UL<<0 as number 31.
715 * Bit 0: instructions named N3, "backported" to esa-mode
716 * Bit 2: z/Architecture mode is active
717 * Bit 7: the store-facility-list-extended facility is installed
718 * Bit 17: the message-security assist is installed
719 * Bit 19: the long-displacement facility is installed
720 * Bit 21: the extended-immediate facility is installed
721 * Bit 22: extended-translation facility 3 is installed
722 * Bit 30: extended-translation facility 3 enhancement facility
723 * These get translated to:
724 * HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
725 * HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
726 * HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
727 * HWCAP_S390_ETF3EH bit 8 (22 && 30).
729 for (i = 0; i < 6; i++)
730 if (test_facility(stfl_bits[i]))
731 elf_hwcap |= 1UL << i;
733 if (test_facility(22) && test_facility(30))
734 elf_hwcap |= HWCAP_S390_ETF3EH;
737 * Check for additional facilities with store-facility-list-extended.
738 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
739 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
740 * as stored by stfl, bits 32-xxx contain additional facilities.
741 * How many facility words are stored depends on the number of
742 * doublewords passed to the instruction. The additional facilities
743 * are:
744 * Bit 42: decimal floating point facility is installed
745 * Bit 44: perform floating point operation facility is installed
746 * translated to:
747 * HWCAP_S390_DFP bit 6 (42 && 44).
749 if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
750 elf_hwcap |= HWCAP_S390_DFP;
753 * Huge page support HWCAP_S390_HPAGE is bit 7.
755 if (MACHINE_HAS_EDAT1)
756 elf_hwcap |= HWCAP_S390_HPAGE;
759 * 64-bit register support for 31-bit processes
760 * HWCAP_S390_HIGH_GPRS is bit 9.
762 elf_hwcap |= HWCAP_S390_HIGH_GPRS;
765 * Transactional execution support HWCAP_S390_TE is bit 10.
767 if (test_facility(50) && test_facility(73))
768 elf_hwcap |= HWCAP_S390_TE;
771 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
772 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
773 * instead of facility bit 129.
775 if (MACHINE_HAS_VX) {
776 elf_hwcap |= HWCAP_S390_VXRS;
777 if (test_facility(134))
778 elf_hwcap |= HWCAP_S390_VXRS_EXT;
779 if (test_facility(135))
780 elf_hwcap |= HWCAP_S390_VXRS_BCD;
784 * Guarded storage support HWCAP_S390_GS is bit 12.
786 if (MACHINE_HAS_GS)
787 elf_hwcap |= HWCAP_S390_GS;
789 get_cpu_id(&cpu_id);
790 add_device_randomness(&cpu_id, sizeof(cpu_id));
791 switch (cpu_id.machine) {
792 case 0x2064:
793 case 0x2066:
794 default: /* Use "z900" as default for 64 bit kernels. */
795 strcpy(elf_platform, "z900");
796 break;
797 case 0x2084:
798 case 0x2086:
799 strcpy(elf_platform, "z990");
800 break;
801 case 0x2094:
802 case 0x2096:
803 strcpy(elf_platform, "z9-109");
804 break;
805 case 0x2097:
806 case 0x2098:
807 strcpy(elf_platform, "z10");
808 break;
809 case 0x2817:
810 case 0x2818:
811 strcpy(elf_platform, "z196");
812 break;
813 case 0x2827:
814 case 0x2828:
815 strcpy(elf_platform, "zEC12");
816 break;
817 case 0x2964:
818 case 0x2965:
819 strcpy(elf_platform, "z13");
820 break;
824 * Virtualization support HWCAP_INT_SIE is bit 0.
826 if (sclp.has_sief2)
827 int_hwcap |= HWCAP_INT_SIE;
829 return 0;
831 arch_initcall(setup_hwcaps);
834 * Add system information as device randomness
836 static void __init setup_randomness(void)
838 struct sysinfo_3_2_2 *vmms;
840 vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE);
841 if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
842 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
843 memblock_free((unsigned long) vmms, PAGE_SIZE);
847 * Find the correct size for the task_struct. This depends on
848 * the size of the struct fpu at the end of the thread_struct
849 * which is embedded in the task_struct.
851 static void __init setup_task_size(void)
853 int task_size = sizeof(struct task_struct);
855 if (!MACHINE_HAS_VX) {
856 task_size -= sizeof(__vector128) * __NUM_VXRS;
857 task_size += sizeof(freg_t) * __NUM_FPRS;
859 arch_task_struct_size = task_size;
863 * Setup function called from init/main.c just after the banner
864 * was printed.
867 void __init setup_arch(char **cmdline_p)
870 * print what head.S has found out about the machine
872 if (MACHINE_IS_VM)
873 pr_info("Linux is running as a z/VM "
874 "guest operating system in 64-bit mode\n");
875 else if (MACHINE_IS_KVM)
876 pr_info("Linux is running under KVM in 64-bit mode\n");
877 else if (MACHINE_IS_LPAR)
878 pr_info("Linux is running natively in 64-bit mode\n");
880 /* Have one command line that is parsed and saved in /proc/cmdline */
881 /* boot_command_line has been already set up in early.c */
882 *cmdline_p = boot_command_line;
884 ROOT_DEV = Root_RAM0;
886 /* Is init_mm really needed? */
887 init_mm.start_code = PAGE_OFFSET;
888 init_mm.end_code = (unsigned long) &_etext;
889 init_mm.end_data = (unsigned long) &_edata;
890 init_mm.brk = (unsigned long) &_end;
892 parse_early_param();
893 #ifdef CONFIG_CRASH_DUMP
894 /* Deactivate elfcorehdr= kernel parameter */
895 elfcorehdr_addr = ELFCORE_ADDR_MAX;
896 #endif
898 os_info_init();
899 setup_ipl();
900 setup_task_size();
902 /* Do some memory reservations *before* memory is added to memblock */
903 reserve_memory_end();
904 reserve_oldmem();
905 reserve_kernel();
906 reserve_initrd();
907 memblock_allow_resize();
909 /* Get information about *all* installed memory */
910 detect_memory_memblock();
912 remove_oldmem();
915 * Make sure all chunks are MAX_ORDER aligned so we don't need the
916 * extra checks that HOLES_IN_ZONE would require.
918 * Is this still required?
920 memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
922 setup_memory_end();
923 setup_memory();
924 dma_contiguous_reserve(memory_end);
926 check_initrd();
927 reserve_crashkernel();
928 #ifdef CONFIG_CRASH_DUMP
930 * Be aware that smp_save_dump_cpus() triggers a system reset.
931 * Therefore CPU and device initialization should be done afterwards.
933 smp_save_dump_cpus();
934 #endif
936 setup_resources();
937 setup_lowcore();
938 smp_fill_possible_mask();
939 cpu_detect_mhz_feature();
940 cpu_init();
941 numa_setup();
942 smp_detect_cpus();
943 topology_init_early();
946 * Create kernel page tables and switch to virtual addressing.
948 paging_init();
950 /* Setup default console */
951 conmode_default();
952 set_preferred_console();
954 /* Setup zfcpdump support */
955 setup_zfcpdump();
957 /* Add system specific data to the random pool */
958 setup_randomness();