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[linux-beck.git] / arch / s390 / kernel / setup.c
1 /*
2  *  arch/s390/kernel/setup.c
3  *
4  *  S390 version
5  *    Copyright (C) IBM Corp. 1999,2010
6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "arch/i386/kernel/setup.c"
10  *    Copyright (C) 1995, Linus Torvalds
11  */
12
13 /*
14  * This file handles the architecture-dependent parts of initialization
15  */
16
17 #define KMSG_COMPONENT "setup"
18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
19
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/stddef.h>
26 #include <linux/unistd.h>
27 #include <linux/ptrace.h>
28 #include <linux/user.h>
29 #include <linux/tty.h>
30 #include <linux/ioport.h>
31 #include <linux/delay.h>
32 #include <linux/init.h>
33 #include <linux/initrd.h>
34 #include <linux/bootmem.h>
35 #include <linux/root_dev.h>
36 #include <linux/console.h>
37 #include <linux/kernel_stat.h>
38 #include <linux/device.h>
39 #include <linux/notifier.h>
40 #include <linux/pfn.h>
41 #include <linux/ctype.h>
42 #include <linux/reboot.h>
43 #include <linux/topology.h>
44 #include <linux/ftrace.h>
45 #include <linux/kexec.h>
46 #include <linux/crash_dump.h>
47 #include <linux/memory.h>
48
49 #include <asm/ipl.h>
50 #include <asm/uaccess.h>
51 #include <asm/system.h>
52 #include <asm/smp.h>
53 #include <asm/mmu_context.h>
54 #include <asm/cpcmd.h>
55 #include <asm/lowcore.h>
56 #include <asm/irq.h>
57 #include <asm/page.h>
58 #include <asm/ptrace.h>
59 #include <asm/sections.h>
60 #include <asm/ebcdic.h>
61 #include <asm/compat.h>
62 #include <asm/kvm_virtio.h>
63 #include <asm/diag.h>
64
65 long psw_kernel_bits    = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
66                           PSW_MASK_EA | PSW_MASK_BA;
67 long psw_user_bits      = PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
68                           PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
69                           PSW_MASK_PSTATE | PSW_ASC_HOME;
70
71 /*
72  * User copy operations.
73  */
74 struct uaccess_ops uaccess;
75 EXPORT_SYMBOL(uaccess);
76
77 /*
78  * Machine setup..
79  */
80 unsigned int console_mode = 0;
81 EXPORT_SYMBOL(console_mode);
82
83 unsigned int console_devno = -1;
84 EXPORT_SYMBOL(console_devno);
85
86 unsigned int console_irq = -1;
87 EXPORT_SYMBOL(console_irq);
88
89 unsigned long elf_hwcap = 0;
90 char elf_platform[ELF_PLATFORM_SIZE];
91
92 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
93
94 int __initdata memory_end_set;
95 unsigned long __initdata memory_end;
96
97 unsigned long VMALLOC_START;
98 EXPORT_SYMBOL(VMALLOC_START);
99
100 unsigned long VMALLOC_END;
101 EXPORT_SYMBOL(VMALLOC_END);
102
103 struct page *vmemmap;
104 EXPORT_SYMBOL(vmemmap);
105
106 /* An array with a pointer to the lowcore of every CPU. */
107 struct _lowcore *lowcore_ptr[NR_CPUS];
108 EXPORT_SYMBOL(lowcore_ptr);
109
110 /*
111  * This is set up by the setup-routine at boot-time
112  * for S390 need to find out, what we have to setup
113  * using address 0x10400 ...
114  */
115
116 #include <asm/setup.h>
117
118 /*
119  * condev= and conmode= setup parameter.
120  */
121
122 static int __init condev_setup(char *str)
123 {
124         int vdev;
125
126         vdev = simple_strtoul(str, &str, 0);
127         if (vdev >= 0 && vdev < 65536) {
128                 console_devno = vdev;
129                 console_irq = -1;
130         }
131         return 1;
132 }
133
134 __setup("condev=", condev_setup);
135
136 static void __init set_preferred_console(void)
137 {
138         if (MACHINE_IS_KVM)
139                 add_preferred_console("hvc", 0, NULL);
140         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
141                 add_preferred_console("ttyS", 0, NULL);
142         else if (CONSOLE_IS_3270)
143                 add_preferred_console("tty3270", 0, NULL);
144 }
145
146 static int __init conmode_setup(char *str)
147 {
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;
162 }
163
164 __setup("conmode=", conmode_setup);
165
166 static void __init conmode_default(void)
167 {
168         char query_buffer[1024];
169         char *ptr;
170
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");
178                 /*
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).
184                  */
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;
191                 }
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
208                 }
209         } else {
210 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
211                 SET_CONSOLE_SCLP;
212 #endif
213         }
214 }
215
216 #ifdef CONFIG_ZFCPDUMP
217 static void __init setup_zfcpdump(unsigned int console_devno)
218 {
219         static char str[41];
220
221         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
222                 return;
223         if (OLDMEM_BASE)
224                 return;
225         if (console_devno != -1)
226                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
227                         ipl_info.data.fcp.dev_id.devno, console_devno);
228         else
229                 sprintf(str, " cio_ignore=all,!0.0.%04x",
230                         ipl_info.data.fcp.dev_id.devno);
231         strcat(boot_command_line, str);
232         console_loglevel = 2;
233 }
234 #else
235 static inline void setup_zfcpdump(unsigned int console_devno) {}
236 #endif /* CONFIG_ZFCPDUMP */
237
238  /*
239  * Reboot, halt and power_off stubs. They just call _machine_restart,
240  * _machine_halt or _machine_power_off. 
241  */
242
243 void machine_restart(char *command)
244 {
245         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
246                 /*
247                  * Only unblank the console if we are called in enabled
248                  * context or a bust_spinlocks cleared the way for us.
249                  */
250                 console_unblank();
251         _machine_restart(command);
252 }
253
254 void machine_halt(void)
255 {
256         if (!in_interrupt() || oops_in_progress)
257                 /*
258                  * Only unblank the console if we are called in enabled
259                  * context or a bust_spinlocks cleared the way for us.
260                  */
261                 console_unblank();
262         _machine_halt();
263 }
264
265 void machine_power_off(void)
266 {
267         if (!in_interrupt() || oops_in_progress)
268                 /*
269                  * Only unblank the console if we are called in enabled
270                  * context or a bust_spinlocks cleared the way for us.
271                  */
272                 console_unblank();
273         _machine_power_off();
274 }
275
276 /*
277  * Dummy power off function.
278  */
279 void (*pm_power_off)(void) = machine_power_off;
280
281 static int __init early_parse_mem(char *p)
282 {
283         memory_end = memparse(p, &p);
284         memory_end_set = 1;
285         return 0;
286 }
287 early_param("mem", early_parse_mem);
288
289 static int __init parse_vmalloc(char *arg)
290 {
291         if (!arg)
292                 return -EINVAL;
293         VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
294         return 0;
295 }
296 early_param("vmalloc", parse_vmalloc);
297
298 unsigned int user_mode = HOME_SPACE_MODE;
299 EXPORT_SYMBOL_GPL(user_mode);
300
301 static int set_amode_primary(void)
302 {
303         psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
304         psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
305 #ifdef CONFIG_COMPAT
306         psw32_user_bits =
307                 (psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
308 #endif
309
310         if (MACHINE_HAS_MVCOS) {
311                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
312                 return 1;
313         } else {
314                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
315                 return 0;
316         }
317 }
318
319 /*
320  * Switch kernel/user addressing modes?
321  */
322 static int __init early_parse_switch_amode(char *p)
323 {
324         user_mode = PRIMARY_SPACE_MODE;
325         return 0;
326 }
327 early_param("switch_amode", early_parse_switch_amode);
328
329 static int __init early_parse_user_mode(char *p)
330 {
331         if (p && strcmp(p, "primary") == 0)
332                 user_mode = PRIMARY_SPACE_MODE;
333         else if (!p || strcmp(p, "home") == 0)
334                 user_mode = HOME_SPACE_MODE;
335         else
336                 return 1;
337         return 0;
338 }
339 early_param("user_mode", early_parse_user_mode);
340
341 static void setup_addressing_mode(void)
342 {
343         if (user_mode == PRIMARY_SPACE_MODE) {
344                 if (set_amode_primary())
345                         pr_info("Address spaces switched, "
346                                 "mvcos available\n");
347                 else
348                         pr_info("Address spaces switched, "
349                                 "mvcos not available\n");
350         }
351 }
352
353 static void __init
354 setup_lowcore(void)
355 {
356         struct _lowcore *lc;
357
358         /*
359          * Setup lowcore for boot cpu
360          */
361         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
362         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
363         lc->restart_psw.mask = psw_kernel_bits;
364         lc->restart_psw.addr =
365                 PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
366         lc->external_new_psw.mask = psw_kernel_bits |
367                 PSW_MASK_DAT | PSW_MASK_MCHECK;
368         lc->external_new_psw.addr =
369                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
370         lc->svc_new_psw.mask = psw_kernel_bits |
371                 PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
372         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
373         lc->program_new_psw.mask = psw_kernel_bits |
374                 PSW_MASK_DAT | PSW_MASK_MCHECK;
375         lc->program_new_psw.addr =
376                 PSW_ADDR_AMODE | (unsigned long) pgm_check_handler;
377         lc->mcck_new_psw.mask = psw_kernel_bits;
378         lc->mcck_new_psw.addr =
379                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
380         lc->io_new_psw.mask = psw_kernel_bits |
381                 PSW_MASK_DAT | PSW_MASK_MCHECK;
382         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
383         lc->clock_comparator = -1ULL;
384         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
385         lc->async_stack = (unsigned long)
386                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
387         lc->panic_stack = (unsigned long)
388                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
389         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
390         lc->thread_info = (unsigned long) &init_thread_union;
391         lc->machine_flags = S390_lowcore.machine_flags;
392         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
393         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
394                MAX_FACILITY_BIT/8);
395 #ifndef CONFIG_64BIT
396         if (MACHINE_HAS_IEEE) {
397                 lc->extended_save_area_addr = (__u32)
398                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
399                 /* enable extended save area */
400                 __ctl_set_bit(14, 29);
401         }
402 #else
403         lc->cmf_hpp = -1ULL;
404         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
405 #endif
406         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
407         lc->async_enter_timer = S390_lowcore.async_enter_timer;
408         lc->exit_timer = S390_lowcore.exit_timer;
409         lc->user_timer = S390_lowcore.user_timer;
410         lc->system_timer = S390_lowcore.system_timer;
411         lc->steal_timer = S390_lowcore.steal_timer;
412         lc->last_update_timer = S390_lowcore.last_update_timer;
413         lc->last_update_clock = S390_lowcore.last_update_clock;
414         lc->ftrace_func = S390_lowcore.ftrace_func;
415         set_prefix((u32)(unsigned long) lc);
416         lowcore_ptr[0] = lc;
417 }
418
419 static struct resource code_resource = {
420         .name  = "Kernel code",
421         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
422 };
423
424 static struct resource data_resource = {
425         .name = "Kernel data",
426         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
427 };
428
429 static struct resource bss_resource = {
430         .name = "Kernel bss",
431         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
432 };
433
434 static struct resource __initdata *standard_resources[] = {
435         &code_resource,
436         &data_resource,
437         &bss_resource,
438 };
439
440 static void __init setup_resources(void)
441 {
442         struct resource *res, *std_res, *sub_res;
443         int i, j;
444
445         code_resource.start = (unsigned long) &_text;
446         code_resource.end = (unsigned long) &_etext - 1;
447         data_resource.start = (unsigned long) &_etext;
448         data_resource.end = (unsigned long) &_edata - 1;
449         bss_resource.start = (unsigned long) &__bss_start;
450         bss_resource.end = (unsigned long) &__bss_stop - 1;
451
452         for (i = 0; i < MEMORY_CHUNKS; i++) {
453                 if (!memory_chunk[i].size)
454                         continue;
455                 if (memory_chunk[i].type == CHUNK_OLDMEM ||
456                     memory_chunk[i].type == CHUNK_CRASHK)
457                         continue;
458                 res = alloc_bootmem_low(sizeof(*res));
459                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
460                 switch (memory_chunk[i].type) {
461                 case CHUNK_READ_WRITE:
462                 case CHUNK_CRASHK:
463                         res->name = "System RAM";
464                         break;
465                 case CHUNK_READ_ONLY:
466                         res->name = "System ROM";
467                         res->flags |= IORESOURCE_READONLY;
468                         break;
469                 default:
470                         res->name = "reserved";
471                 }
472                 res->start = memory_chunk[i].addr;
473                 res->end = res->start + memory_chunk[i].size - 1;
474                 request_resource(&iomem_resource, res);
475
476                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
477                         std_res = standard_resources[j];
478                         if (std_res->start < res->start ||
479                             std_res->start > res->end)
480                                 continue;
481                         if (std_res->end > res->end) {
482                                 sub_res = alloc_bootmem_low(sizeof(*sub_res));
483                                 *sub_res = *std_res;
484                                 sub_res->end = res->end;
485                                 std_res->start = res->end + 1;
486                                 request_resource(res, sub_res);
487                         } else {
488                                 request_resource(res, std_res);
489                         }
490                 }
491         }
492 }
493
494 unsigned long real_memory_size;
495 EXPORT_SYMBOL_GPL(real_memory_size);
496
497 static void __init setup_memory_end(void)
498 {
499         unsigned long vmax, vmalloc_size, tmp;
500         int i;
501
502
503 #ifdef CONFIG_ZFCPDUMP
504         if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
505                 memory_end = ZFCPDUMP_HSA_SIZE;
506                 memory_end_set = 1;
507         }
508 #endif
509         real_memory_size = 0;
510         memory_end &= PAGE_MASK;
511
512         /*
513          * Make sure all chunks are MAX_ORDER aligned so we don't need the
514          * extra checks that HOLES_IN_ZONE would require.
515          */
516         for (i = 0; i < MEMORY_CHUNKS; i++) {
517                 unsigned long start, end;
518                 struct mem_chunk *chunk;
519                 unsigned long align;
520
521                 chunk = &memory_chunk[i];
522                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
523                 start = (chunk->addr + align - 1) & ~(align - 1);
524                 end = (chunk->addr + chunk->size) & ~(align - 1);
525                 if (start >= end)
526                         memset(chunk, 0, sizeof(*chunk));
527                 else {
528                         chunk->addr = start;
529                         chunk->size = end - start;
530                 }
531                 real_memory_size = max(real_memory_size,
532                                        chunk->addr + chunk->size);
533         }
534
535         /* Choose kernel address space layout: 2, 3, or 4 levels. */
536 #ifdef CONFIG_64BIT
537         vmalloc_size = VMALLOC_END ?: 128UL << 30;
538         tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
539         tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
540         if (tmp <= (1UL << 42))
541                 vmax = 1UL << 42;       /* 3-level kernel page table */
542         else
543                 vmax = 1UL << 53;       /* 4-level kernel page table */
544 #else
545         vmalloc_size = VMALLOC_END ?: 96UL << 20;
546         vmax = 1UL << 31;               /* 2-level kernel page table */
547 #endif
548         /* vmalloc area is at the end of the kernel address space. */
549         VMALLOC_END = vmax;
550         VMALLOC_START = vmax - vmalloc_size;
551
552         /* Split remaining virtual space between 1:1 mapping & vmemmap array */
553         tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
554         tmp = VMALLOC_START - tmp * sizeof(struct page);
555         tmp &= ~((vmax >> 11) - 1);     /* align to page table level */
556         tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
557         vmemmap = (struct page *) tmp;
558
559         /* Take care that memory_end is set and <= vmemmap */
560         memory_end = min(memory_end ?: real_memory_size, tmp);
561
562         /* Fixup memory chunk array to fit into 0..memory_end */
563         for (i = 0; i < MEMORY_CHUNKS; i++) {
564                 struct mem_chunk *chunk = &memory_chunk[i];
565
566                 if (chunk->addr >= memory_end) {
567                         memset(chunk, 0, sizeof(*chunk));
568                         continue;
569                 }
570                 if (chunk->addr + chunk->size > memory_end)
571                         chunk->size = memory_end - chunk->addr;
572         }
573 }
574
575 void *restart_stack __attribute__((__section__(".data")));
576
577 /*
578  * Setup new PSW and allocate stack for PSW restart interrupt
579  */
580 static void __init setup_restart_psw(void)
581 {
582         psw_t psw;
583
584         restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
585         restart_stack += ASYNC_SIZE;
586
587         /*
588          * Setup restart PSW for absolute zero lowcore. This is necesary
589          * if PSW restart is done on an offline CPU that has lowcore zero
590          */
591         psw.mask = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA | PSW_MASK_BA;
592         psw.addr = PSW_ADDR_AMODE | (unsigned long) psw_restart_int_handler;
593         copy_to_absolute_zero(&S390_lowcore.restart_psw, &psw, sizeof(psw));
594 }
595
596 static void __init setup_vmcoreinfo(void)
597 {
598 #ifdef CONFIG_KEXEC
599         unsigned long ptr = paddr_vmcoreinfo_note();
600
601         copy_to_absolute_zero(&S390_lowcore.vmcore_info, &ptr, sizeof(ptr));
602 #endif
603 }
604
605 #ifdef CONFIG_CRASH_DUMP
606
607 /*
608  * Find suitable location for crashkernel memory
609  */
610 static unsigned long __init find_crash_base(unsigned long crash_size,
611                                             char **msg)
612 {
613         unsigned long crash_base;
614         struct mem_chunk *chunk;
615         int i;
616
617         if (memory_chunk[0].size < crash_size) {
618                 *msg = "first memory chunk must be at least crashkernel size";
619                 return 0;
620         }
621         if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
622                 return OLDMEM_BASE;
623
624         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
625                 chunk = &memory_chunk[i];
626                 if (chunk->size == 0)
627                         continue;
628                 if (chunk->type != CHUNK_READ_WRITE)
629                         continue;
630                 if (chunk->size < crash_size)
631                         continue;
632                 crash_base = (chunk->addr + chunk->size) - crash_size;
633                 if (crash_base < crash_size)
634                         continue;
635                 if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
636                         continue;
637                 if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
638                         continue;
639                 return crash_base;
640         }
641         *msg = "no suitable area found";
642         return 0;
643 }
644
645 /*
646  * Check if crash_base and crash_size is valid
647  */
648 static int __init verify_crash_base(unsigned long crash_base,
649                                     unsigned long crash_size,
650                                     char **msg)
651 {
652         struct mem_chunk *chunk;
653         int i;
654
655         /*
656          * Because we do the swap to zero, we must have at least 'crash_size'
657          * bytes free space before crash_base
658          */
659         if (crash_size > crash_base) {
660                 *msg = "crashkernel offset must be greater than size";
661                 return -EINVAL;
662         }
663
664         /* First memory chunk must be at least crash_size */
665         if (memory_chunk[0].size < crash_size) {
666                 *msg = "first memory chunk must be at least crashkernel size";
667                 return -EINVAL;
668         }
669         /* Check if we fit into the respective memory chunk */
670         for (i = 0; i < MEMORY_CHUNKS; i++) {
671                 chunk = &memory_chunk[i];
672                 if (chunk->size == 0)
673                         continue;
674                 if (crash_base < chunk->addr)
675                         continue;
676                 if (crash_base >= chunk->addr + chunk->size)
677                         continue;
678                 /* we have found the memory chunk */
679                 if (crash_base + crash_size > chunk->addr + chunk->size) {
680                         *msg = "selected memory chunk is too small for "
681                                 "crashkernel memory";
682                         return -EINVAL;
683                 }
684                 return 0;
685         }
686         *msg = "invalid memory range specified";
687         return -EINVAL;
688 }
689
690 /*
691  * Reserve kdump memory by creating a memory hole in the mem_chunk array
692  */
693 static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
694                                          int type)
695 {
696         create_mem_hole(memory_chunk, addr, size, type);
697 }
698
699 /*
700  * When kdump is enabled, we have to ensure that no memory from
701  * the area [0 - crashkernel memory size] and
702  * [crashk_res.start - crashk_res.end] is set offline.
703  */
704 static int kdump_mem_notifier(struct notifier_block *nb,
705                               unsigned long action, void *data)
706 {
707         struct memory_notify *arg = data;
708
709         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
710                 return NOTIFY_BAD;
711         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
712                 return NOTIFY_OK;
713         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
714                 return NOTIFY_OK;
715         return NOTIFY_BAD;
716 }
717
718 static struct notifier_block kdump_mem_nb = {
719         .notifier_call = kdump_mem_notifier,
720 };
721
722 #endif
723
724 /*
725  * Make sure that oldmem, where the dump is stored, is protected
726  */
727 static void reserve_oldmem(void)
728 {
729 #ifdef CONFIG_CRASH_DUMP
730         if (!OLDMEM_BASE)
731                 return;
732
733         reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
734         reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
735                               CHUNK_OLDMEM);
736         if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
737                 saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
738         else
739                 saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
740 #endif
741 }
742
743 /*
744  * Reserve memory for kdump kernel to be loaded with kexec
745  */
746 static void __init reserve_crashkernel(void)
747 {
748 #ifdef CONFIG_CRASH_DUMP
749         unsigned long long crash_base, crash_size;
750         char *msg;
751         int rc;
752
753         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
754                                &crash_base);
755         if (rc || crash_size == 0)
756                 return;
757         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
758         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
759         if (register_memory_notifier(&kdump_mem_nb))
760                 return;
761         if (!crash_base)
762                 crash_base = find_crash_base(crash_size, &msg);
763         if (!crash_base) {
764                 pr_info("crashkernel reservation failed: %s\n", msg);
765                 unregister_memory_notifier(&kdump_mem_nb);
766                 return;
767         }
768         if (verify_crash_base(crash_base, crash_size, &msg)) {
769                 pr_info("crashkernel reservation failed: %s\n", msg);
770                 unregister_memory_notifier(&kdump_mem_nb);
771                 return;
772         }
773         if (!OLDMEM_BASE && MACHINE_IS_VM)
774                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
775         crashk_res.start = crash_base;
776         crashk_res.end = crash_base + crash_size - 1;
777         insert_resource(&iomem_resource, &crashk_res);
778         reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
779         pr_info("Reserving %lluMB of memory at %lluMB "
780                 "for crashkernel (System RAM: %luMB)\n",
781                 crash_size >> 20, crash_base >> 20, memory_end >> 20);
782 #endif
783 }
784
785 static void __init
786 setup_memory(void)
787 {
788         unsigned long bootmap_size;
789         unsigned long start_pfn, end_pfn;
790         int i;
791
792         /*
793          * partially used pages are not usable - thus
794          * we are rounding upwards:
795          */
796         start_pfn = PFN_UP(__pa(&_end));
797         end_pfn = max_pfn = PFN_DOWN(memory_end);
798
799 #ifdef CONFIG_BLK_DEV_INITRD
800         /*
801          * Move the initrd in case the bitmap of the bootmem allocater
802          * would overwrite it.
803          */
804
805         if (INITRD_START && INITRD_SIZE) {
806                 unsigned long bmap_size;
807                 unsigned long start;
808
809                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
810                 bmap_size = PFN_PHYS(bmap_size);
811
812                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
813                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
814
815 #ifdef CONFIG_CRASH_DUMP
816                         if (OLDMEM_BASE) {
817                                 /* Move initrd behind kdump oldmem */
818                                 if (start + INITRD_SIZE > OLDMEM_BASE &&
819                                     start < OLDMEM_BASE + OLDMEM_SIZE)
820                                         start = OLDMEM_BASE + OLDMEM_SIZE;
821                         }
822 #endif
823                         if (start + INITRD_SIZE > memory_end) {
824                                 pr_err("initrd extends beyond end of "
825                                        "memory (0x%08lx > 0x%08lx) "
826                                        "disabling initrd\n",
827                                        start + INITRD_SIZE, memory_end);
828                                 INITRD_START = INITRD_SIZE = 0;
829                         } else {
830                                 pr_info("Moving initrd (0x%08lx -> "
831                                         "0x%08lx, size: %ld)\n",
832                                         INITRD_START, start, INITRD_SIZE);
833                                 memmove((void *) start, (void *) INITRD_START,
834                                         INITRD_SIZE);
835                                 INITRD_START = start;
836                         }
837                 }
838         }
839 #endif
840
841         /*
842          * Initialize the boot-time allocator
843          */
844         bootmap_size = init_bootmem(start_pfn, end_pfn);
845
846         /*
847          * Register RAM areas with the bootmem allocator.
848          */
849
850         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
851                 unsigned long start_chunk, end_chunk, pfn;
852
853                 if (memory_chunk[i].type != CHUNK_READ_WRITE &&
854                     memory_chunk[i].type != CHUNK_CRASHK)
855                         continue;
856                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
857                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
858                 end_chunk = min(end_chunk, end_pfn);
859                 if (start_chunk >= end_chunk)
860                         continue;
861                 add_active_range(0, start_chunk, end_chunk);
862                 pfn = max(start_chunk, start_pfn);
863                 for (; pfn < end_chunk; pfn++)
864                         page_set_storage_key(PFN_PHYS(pfn),
865                                              PAGE_DEFAULT_KEY, 0);
866         }
867
868         psw_set_key(PAGE_DEFAULT_KEY);
869
870         free_bootmem_with_active_regions(0, max_pfn);
871
872         /*
873          * Reserve memory used for lowcore/command line/kernel image.
874          */
875         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
876         reserve_bootmem((unsigned long)_stext,
877                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
878                         BOOTMEM_DEFAULT);
879         /*
880          * Reserve the bootmem bitmap itself as well. We do this in two
881          * steps (first step was init_bootmem()) because this catches
882          * the (very unlikely) case of us accidentally initializing the
883          * bootmem allocator with an invalid RAM area.
884          */
885         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
886                         BOOTMEM_DEFAULT);
887
888 #ifdef CONFIG_CRASH_DUMP
889         if (crashk_res.start)
890                 reserve_bootmem(crashk_res.start,
891                                 crashk_res.end - crashk_res.start + 1,
892                                 BOOTMEM_DEFAULT);
893         if (is_kdump_kernel())
894                 reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
895                                 PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
896 #endif
897 #ifdef CONFIG_BLK_DEV_INITRD
898         if (INITRD_START && INITRD_SIZE) {
899                 if (INITRD_START + INITRD_SIZE <= memory_end) {
900                         reserve_bootmem(INITRD_START, INITRD_SIZE,
901                                         BOOTMEM_DEFAULT);
902                         initrd_start = INITRD_START;
903                         initrd_end = initrd_start + INITRD_SIZE;
904                 } else {
905                         pr_err("initrd extends beyond end of "
906                                "memory (0x%08lx > 0x%08lx) "
907                                "disabling initrd\n",
908                                initrd_start + INITRD_SIZE, memory_end);
909                         initrd_start = initrd_end = 0;
910                 }
911         }
912 #endif
913 }
914
915 /*
916  * Setup hardware capabilities.
917  */
918 static void __init setup_hwcaps(void)
919 {
920         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
921         struct cpuid cpu_id;
922         int i;
923
924         /*
925          * The store facility list bits numbers as found in the principles
926          * of operation are numbered with bit 1UL<<31 as number 0 to
927          * bit 1UL<<0 as number 31.
928          *   Bit 0: instructions named N3, "backported" to esa-mode
929          *   Bit 2: z/Architecture mode is active
930          *   Bit 7: the store-facility-list-extended facility is installed
931          *   Bit 17: the message-security assist is installed
932          *   Bit 19: the long-displacement facility is installed
933          *   Bit 21: the extended-immediate facility is installed
934          *   Bit 22: extended-translation facility 3 is installed
935          *   Bit 30: extended-translation facility 3 enhancement facility
936          * These get translated to:
937          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
938          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
939          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
940          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
941          */
942         for (i = 0; i < 6; i++)
943                 if (test_facility(stfl_bits[i]))
944                         elf_hwcap |= 1UL << i;
945
946         if (test_facility(22) && test_facility(30))
947                 elf_hwcap |= HWCAP_S390_ETF3EH;
948
949         /*
950          * Check for additional facilities with store-facility-list-extended.
951          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
952          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
953          * as stored by stfl, bits 32-xxx contain additional facilities.
954          * How many facility words are stored depends on the number of
955          * doublewords passed to the instruction. The additional facilities
956          * are:
957          *   Bit 42: decimal floating point facility is installed
958          *   Bit 44: perform floating point operation facility is installed
959          * translated to:
960          *   HWCAP_S390_DFP bit 6 (42 && 44).
961          */
962         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
963                 elf_hwcap |= HWCAP_S390_DFP;
964
965         /*
966          * Huge page support HWCAP_S390_HPAGE is bit 7.
967          */
968         if (MACHINE_HAS_HPAGE)
969                 elf_hwcap |= HWCAP_S390_HPAGE;
970
971         /*
972          * 64-bit register support for 31-bit processes
973          * HWCAP_S390_HIGH_GPRS is bit 9.
974          */
975         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
976
977         get_cpu_id(&cpu_id);
978         switch (cpu_id.machine) {
979         case 0x9672:
980 #if !defined(CONFIG_64BIT)
981         default:        /* Use "g5" as default for 31 bit kernels. */
982 #endif
983                 strcpy(elf_platform, "g5");
984                 break;
985         case 0x2064:
986         case 0x2066:
987 #if defined(CONFIG_64BIT)
988         default:        /* Use "z900" as default for 64 bit kernels. */
989 #endif
990                 strcpy(elf_platform, "z900");
991                 break;
992         case 0x2084:
993         case 0x2086:
994                 strcpy(elf_platform, "z990");
995                 break;
996         case 0x2094:
997         case 0x2096:
998                 strcpy(elf_platform, "z9-109");
999                 break;
1000         case 0x2097:
1001         case 0x2098:
1002                 strcpy(elf_platform, "z10");
1003                 break;
1004         case 0x2817:
1005         case 0x2818:
1006                 strcpy(elf_platform, "z196");
1007                 break;
1008         }
1009 }
1010
1011 /*
1012  * Setup function called from init/main.c just after the banner
1013  * was printed.
1014  */
1015
1016 void __init
1017 setup_arch(char **cmdline_p)
1018 {
1019         /*
1020          * print what head.S has found out about the machine
1021          */
1022 #ifndef CONFIG_64BIT
1023         if (MACHINE_IS_VM)
1024                 pr_info("Linux is running as a z/VM "
1025                         "guest operating system in 31-bit mode\n");
1026         else if (MACHINE_IS_LPAR)
1027                 pr_info("Linux is running natively in 31-bit mode\n");
1028         if (MACHINE_HAS_IEEE)
1029                 pr_info("The hardware system has IEEE compatible "
1030                         "floating point units\n");
1031         else
1032                 pr_info("The hardware system has no IEEE compatible "
1033                         "floating point units\n");
1034 #else /* CONFIG_64BIT */
1035         if (MACHINE_IS_VM)
1036                 pr_info("Linux is running as a z/VM "
1037                         "guest operating system in 64-bit mode\n");
1038         else if (MACHINE_IS_KVM)
1039                 pr_info("Linux is running under KVM in 64-bit mode\n");
1040         else if (MACHINE_IS_LPAR)
1041                 pr_info("Linux is running natively in 64-bit mode\n");
1042 #endif /* CONFIG_64BIT */
1043
1044         /* Have one command line that is parsed and saved in /proc/cmdline */
1045         /* boot_command_line has been already set up in early.c */
1046         *cmdline_p = boot_command_line;
1047
1048         ROOT_DEV = Root_RAM0;
1049
1050         init_mm.start_code = PAGE_OFFSET;
1051         init_mm.end_code = (unsigned long) &_etext;
1052         init_mm.end_data = (unsigned long) &_edata;
1053         init_mm.brk = (unsigned long) &_end;
1054
1055         if (MACHINE_HAS_MVCOS)
1056                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
1057         else
1058                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
1059
1060         parse_early_param();
1061
1062         setup_ipl();
1063         setup_memory_end();
1064         setup_addressing_mode();
1065         reserve_oldmem();
1066         reserve_crashkernel();
1067         setup_memory();
1068         setup_resources();
1069         setup_vmcoreinfo();
1070         setup_restart_psw();
1071         setup_lowcore();
1072
1073         cpu_init();
1074         s390_init_cpu_topology();
1075
1076         /*
1077          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
1078          */
1079         setup_hwcaps();
1080
1081         /*
1082          * Create kernel page tables and switch to virtual addressing.
1083          */
1084         paging_init();
1085
1086         /* Setup default console */
1087         conmode_default();
1088         set_preferred_console();
1089
1090         /* Setup zfcpdump support */
1091         setup_zfcpdump(console_devno);
1092 }