[S390] Have s390 use add_active_range() and free_area_init_nodes.
[linux-2.6.git] / arch / s390 / kernel / setup.c
1 /*
2  *  arch/s390/kernel/setup.c
3  *
4  *  S390 version
5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
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 #include <linux/errno.h>
18 #include <linux/module.h>
19 #include <linux/sched.h>
20 #include <linux/kernel.h>
21 #include <linux/mm.h>
22 #include <linux/stddef.h>
23 #include <linux/unistd.h>
24 #include <linux/ptrace.h>
25 #include <linux/slab.h>
26 #include <linux/user.h>
27 #include <linux/a.out.h>
28 #include <linux/tty.h>
29 #include <linux/ioport.h>
30 #include <linux/delay.h>
31 #include <linux/init.h>
32 #include <linux/initrd.h>
33 #include <linux/bootmem.h>
34 #include <linux/root_dev.h>
35 #include <linux/console.h>
36 #include <linux/seq_file.h>
37 #include <linux/kernel_stat.h>
38 #include <linux/device.h>
39 #include <linux/notifier.h>
40 #include <linux/pfn.h>
41
42 #include <asm/uaccess.h>
43 #include <asm/system.h>
44 #include <asm/smp.h>
45 #include <asm/mmu_context.h>
46 #include <asm/cpcmd.h>
47 #include <asm/lowcore.h>
48 #include <asm/irq.h>
49 #include <asm/page.h>
50 #include <asm/ptrace.h>
51 #include <asm/sections.h>
52
53 /*
54  * User copy operations.
55  */
56 struct uaccess_ops uaccess;
57 EXPORT_SYMBOL_GPL(uaccess);
58
59 /*
60  * Machine setup..
61  */
62 unsigned int console_mode = 0;
63 unsigned int console_devno = -1;
64 unsigned int console_irq = -1;
65 unsigned long memory_size = 0;
66 unsigned long machine_flags = 0;
67 struct {
68         unsigned long addr, size, type;
69 } memory_chunk[MEMORY_CHUNKS] = { { 0 } };
70 #define CHUNK_READ_WRITE 0
71 #define CHUNK_READ_ONLY 1
72 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
73 static unsigned long __initdata memory_end;
74
75 /*
76  * This is set up by the setup-routine at boot-time
77  * for S390 need to find out, what we have to setup
78  * using address 0x10400 ...
79  */
80
81 #include <asm/setup.h>
82
83 static struct resource code_resource = {
84         .name  = "Kernel code",
85         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
86 };
87
88 static struct resource data_resource = {
89         .name = "Kernel data",
90         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
91 };
92
93 /*
94  * cpu_init() initializes state that is per-CPU.
95  */
96 void __devinit cpu_init (void)
97 {
98         int addr = hard_smp_processor_id();
99
100         /*
101          * Store processor id in lowcore (used e.g. in timer_interrupt)
102          */
103         asm volatile("stidp %0": "=m" (S390_lowcore.cpu_data.cpu_id));
104         S390_lowcore.cpu_data.cpu_addr = addr;
105
106         /*
107          * Force FPU initialization:
108          */
109         clear_thread_flag(TIF_USEDFPU);
110         clear_used_math();
111
112         atomic_inc(&init_mm.mm_count);
113         current->active_mm = &init_mm;
114         if (current->mm)
115                 BUG();
116         enter_lazy_tlb(&init_mm, current);
117 }
118
119 /*
120  * VM halt and poweroff setup routines
121  */
122 char vmhalt_cmd[128] = "";
123 char vmpoff_cmd[128] = "";
124 char vmpanic_cmd[128] = "";
125
126 static inline void strncpy_skip_quote(char *dst, char *src, int n)
127 {
128         int sx, dx;
129
130         dx = 0;
131         for (sx = 0; src[sx] != 0; sx++) {
132                 if (src[sx] == '"') continue;
133                 dst[dx++] = src[sx];
134                 if (dx >= n) break;
135         }
136 }
137
138 static int __init vmhalt_setup(char *str)
139 {
140         strncpy_skip_quote(vmhalt_cmd, str, 127);
141         vmhalt_cmd[127] = 0;
142         return 1;
143 }
144
145 __setup("vmhalt=", vmhalt_setup);
146
147 static int __init vmpoff_setup(char *str)
148 {
149         strncpy_skip_quote(vmpoff_cmd, str, 127);
150         vmpoff_cmd[127] = 0;
151         return 1;
152 }
153
154 __setup("vmpoff=", vmpoff_setup);
155
156 static int vmpanic_notify(struct notifier_block *self, unsigned long event,
157                           void *data)
158 {
159         if (MACHINE_IS_VM && strlen(vmpanic_cmd) > 0)
160                 cpcmd(vmpanic_cmd, NULL, 0, NULL);
161
162         return NOTIFY_OK;
163 }
164
165 #define PANIC_PRI_VMPANIC       0
166
167 static struct notifier_block vmpanic_nb = {
168         .notifier_call = vmpanic_notify,
169         .priority = PANIC_PRI_VMPANIC
170 };
171
172 static int __init vmpanic_setup(char *str)
173 {
174         static int register_done __initdata = 0;
175
176         strncpy_skip_quote(vmpanic_cmd, str, 127);
177         vmpanic_cmd[127] = 0;
178         if (!register_done) {
179                 register_done = 1;
180                 atomic_notifier_chain_register(&panic_notifier_list,
181                                                &vmpanic_nb);
182         }
183         return 1;
184 }
185
186 __setup("vmpanic=", vmpanic_setup);
187
188 /*
189  * condev= and conmode= setup parameter.
190  */
191
192 static int __init condev_setup(char *str)
193 {
194         int vdev;
195
196         vdev = simple_strtoul(str, &str, 0);
197         if (vdev >= 0 && vdev < 65536) {
198                 console_devno = vdev;
199                 console_irq = -1;
200         }
201         return 1;
202 }
203
204 __setup("condev=", condev_setup);
205
206 static int __init conmode_setup(char *str)
207 {
208 #if defined(CONFIG_SCLP_CONSOLE)
209         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
210                 SET_CONSOLE_SCLP;
211 #endif
212 #if defined(CONFIG_TN3215_CONSOLE)
213         if (strncmp(str, "3215", 5) == 0)
214                 SET_CONSOLE_3215;
215 #endif
216 #if defined(CONFIG_TN3270_CONSOLE)
217         if (strncmp(str, "3270", 5) == 0)
218                 SET_CONSOLE_3270;
219 #endif
220         return 1;
221 }
222
223 __setup("conmode=", conmode_setup);
224
225 static void __init conmode_default(void)
226 {
227         char query_buffer[1024];
228         char *ptr;
229
230         if (MACHINE_IS_VM) {
231                 __cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
232                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
233                 ptr = strstr(query_buffer, "SUBCHANNEL =");
234                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
235                 __cpcmd("QUERY TERM", query_buffer, 1024, NULL);
236                 ptr = strstr(query_buffer, "CONMODE");
237                 /*
238                  * Set the conmode to 3215 so that the device recognition 
239                  * will set the cu_type of the console to 3215. If the
240                  * conmode is 3270 and we don't set it back then both
241                  * 3215 and the 3270 driver will try to access the console
242                  * device (3215 as console and 3270 as normal tty).
243                  */
244                 __cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
245                 if (ptr == NULL) {
246 #if defined(CONFIG_SCLP_CONSOLE)
247                         SET_CONSOLE_SCLP;
248 #endif
249                         return;
250                 }
251                 if (strncmp(ptr + 8, "3270", 4) == 0) {
252 #if defined(CONFIG_TN3270_CONSOLE)
253                         SET_CONSOLE_3270;
254 #elif defined(CONFIG_TN3215_CONSOLE)
255                         SET_CONSOLE_3215;
256 #elif defined(CONFIG_SCLP_CONSOLE)
257                         SET_CONSOLE_SCLP;
258 #endif
259                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
260 #if defined(CONFIG_TN3215_CONSOLE)
261                         SET_CONSOLE_3215;
262 #elif defined(CONFIG_TN3270_CONSOLE)
263                         SET_CONSOLE_3270;
264 #elif defined(CONFIG_SCLP_CONSOLE)
265                         SET_CONSOLE_SCLP;
266 #endif
267                 }
268         } else if (MACHINE_IS_P390) {
269 #if defined(CONFIG_TN3215_CONSOLE)
270                 SET_CONSOLE_3215;
271 #elif defined(CONFIG_TN3270_CONSOLE)
272                 SET_CONSOLE_3270;
273 #endif
274         } else {
275 #if defined(CONFIG_SCLP_CONSOLE)
276                 SET_CONSOLE_SCLP;
277 #endif
278         }
279 }
280
281 #ifdef CONFIG_SMP
282 extern void machine_restart_smp(char *);
283 extern void machine_halt_smp(void);
284 extern void machine_power_off_smp(void);
285
286 void (*_machine_restart)(char *command) = machine_restart_smp;
287 void (*_machine_halt)(void) = machine_halt_smp;
288 void (*_machine_power_off)(void) = machine_power_off_smp;
289 #else
290 /*
291  * Reboot, halt and power_off routines for non SMP.
292  */
293 static void do_machine_restart_nonsmp(char * __unused)
294 {
295         do_reipl();
296 }
297
298 static void do_machine_halt_nonsmp(void)
299 {
300         if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
301                 cpcmd(vmhalt_cmd, NULL, 0, NULL);
302         signal_processor(smp_processor_id(), sigp_stop_and_store_status);
303 }
304
305 static void do_machine_power_off_nonsmp(void)
306 {
307         if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
308                 cpcmd(vmpoff_cmd, NULL, 0, NULL);
309         signal_processor(smp_processor_id(), sigp_stop_and_store_status);
310 }
311
312 void (*_machine_restart)(char *command) = do_machine_restart_nonsmp;
313 void (*_machine_halt)(void) = do_machine_halt_nonsmp;
314 void (*_machine_power_off)(void) = do_machine_power_off_nonsmp;
315 #endif
316
317  /*
318  * Reboot, halt and power_off stubs. They just call _machine_restart,
319  * _machine_halt or _machine_power_off. 
320  */
321
322 void machine_restart(char *command)
323 {
324         if (!in_interrupt() || oops_in_progress)
325                 /*
326                  * Only unblank the console if we are called in enabled
327                  * context or a bust_spinlocks cleared the way for us.
328                  */
329                 console_unblank();
330         _machine_restart(command);
331 }
332
333 void machine_halt(void)
334 {
335         if (!in_interrupt() || oops_in_progress)
336                 /*
337                  * Only unblank the console if we are called in enabled
338                  * context or a bust_spinlocks cleared the way for us.
339                  */
340                 console_unblank();
341         _machine_halt();
342 }
343
344 void machine_power_off(void)
345 {
346         if (!in_interrupt() || oops_in_progress)
347                 /*
348                  * Only unblank the console if we are called in enabled
349                  * context or a bust_spinlocks cleared the way for us.
350                  */
351                 console_unblank();
352         _machine_power_off();
353 }
354
355 /*
356  * Dummy power off function.
357  */
358 void (*pm_power_off)(void) = machine_power_off;
359
360 static int __init early_parse_mem(char *p)
361 {
362         memory_end = memparse(p, &p);
363         return 0;
364 }
365 early_param("mem", early_parse_mem);
366
367 /*
368  * "ipldelay=XXX[sm]" sets ipl delay in seconds or minutes
369  */
370 static int __init early_parse_ipldelay(char *p)
371 {
372         unsigned long delay = 0;
373
374         delay = simple_strtoul(p, &p, 0);
375
376         switch (*p) {
377         case 's':
378         case 'S':
379                 delay *= 1000000;
380                 break;
381         case 'm':
382         case 'M':
383                 delay *= 60 * 1000000;
384         }
385
386         /* now wait for the requested amount of time */
387         udelay(delay);
388
389         return 0;
390 }
391 early_param("ipldelay", early_parse_ipldelay);
392
393 static void __init
394 setup_lowcore(void)
395 {
396         struct _lowcore *lc;
397         int lc_pages;
398
399         /*
400          * Setup lowcore for boot cpu
401          */
402         lc_pages = sizeof(void *) == 8 ? 2 : 1;
403         lc = (struct _lowcore *)
404                 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
405         memset(lc, 0, lc_pages * PAGE_SIZE);
406         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
407         lc->restart_psw.addr =
408                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
409         lc->external_new_psw.mask = PSW_KERNEL_BITS;
410         lc->external_new_psw.addr =
411                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
412         lc->svc_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
413         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
414         lc->program_new_psw.mask = PSW_KERNEL_BITS;
415         lc->program_new_psw.addr =
416                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
417         lc->mcck_new_psw.mask =
418                 PSW_KERNEL_BITS & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
419         lc->mcck_new_psw.addr =
420                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
421         lc->io_new_psw.mask = PSW_KERNEL_BITS;
422         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
423         lc->ipl_device = S390_lowcore.ipl_device;
424         lc->jiffy_timer = -1LL;
425         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
426         lc->async_stack = (unsigned long)
427                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
428         lc->panic_stack = (unsigned long)
429                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
430         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
431         lc->thread_info = (unsigned long) &init_thread_union;
432 #ifndef CONFIG_64BIT
433         if (MACHINE_HAS_IEEE) {
434                 lc->extended_save_area_addr = (__u32)
435                         __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
436                 /* enable extended save area */
437                 ctl_set_bit(14, 29);
438         }
439 #endif
440         set_prefix((u32)(unsigned long) lc);
441 }
442
443 static void __init
444 setup_resources(void)
445 {
446         struct resource *res;
447         int i;
448
449         code_resource.start = (unsigned long) &_text;
450         code_resource.end = (unsigned long) &_etext - 1;
451         data_resource.start = (unsigned long) &_etext;
452         data_resource.end = (unsigned long) &_edata - 1;
453
454         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
455                 res = alloc_bootmem_low(sizeof(struct resource));
456                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
457                 switch (memory_chunk[i].type) {
458                 case CHUNK_READ_WRITE:
459                         res->name = "System RAM";
460                         break;
461                 case CHUNK_READ_ONLY:
462                         res->name = "System ROM";
463                         res->flags |= IORESOURCE_READONLY;
464                         break;
465                 default:
466                         res->name = "reserved";
467                 }
468                 res->start = memory_chunk[i].addr;
469                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
470                 request_resource(&iomem_resource, res);
471                 request_resource(res, &code_resource);
472                 request_resource(res, &data_resource);
473         }
474 }
475
476 static void __init
477 setup_memory(void)
478 {
479         unsigned long bootmap_size;
480         unsigned long start_pfn, end_pfn, init_pfn;
481         int i;
482
483         /*
484          * partially used pages are not usable - thus
485          * we are rounding upwards:
486          */
487         start_pfn = PFN_UP(__pa(&_end));
488         end_pfn = max_pfn = PFN_DOWN(memory_end);
489
490         /* Initialize storage key for kernel pages */
491         for (init_pfn = 0 ; init_pfn < start_pfn; init_pfn++)
492                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
493
494 #ifdef CONFIG_BLK_DEV_INITRD
495         /*
496          * Move the initrd in case the bitmap of the bootmem allocater
497          * would overwrite it.
498          */
499
500         if (INITRD_START && INITRD_SIZE) {
501                 unsigned long bmap_size;
502                 unsigned long start;
503
504                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
505                 bmap_size = PFN_PHYS(bmap_size);
506
507                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
508                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
509
510                         if (start + INITRD_SIZE > memory_end) {
511                                 printk("initrd extends beyond end of memory "
512                                        "(0x%08lx > 0x%08lx)\n"
513                                        "disabling initrd\n",
514                                        start + INITRD_SIZE, memory_end);
515                                 INITRD_START = INITRD_SIZE = 0;
516                         } else {
517                                 printk("Moving initrd (0x%08lx -> 0x%08lx, "
518                                        "size: %ld)\n",
519                                        INITRD_START, start, INITRD_SIZE);
520                                 memmove((void *) start, (void *) INITRD_START,
521                                         INITRD_SIZE);
522                                 INITRD_START = start;
523                         }
524                 }
525         }
526 #endif
527
528         /*
529          * Initialize the boot-time allocator
530          */
531         bootmap_size = init_bootmem(start_pfn, end_pfn);
532
533         /*
534          * Register RAM areas with the bootmem allocator.
535          */
536
537         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
538                 unsigned long start_chunk, end_chunk, pfn;
539
540                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
541                         continue;
542                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
543                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size) - 1;
544                 end_chunk = min(end_chunk, end_pfn);
545                 if (start_chunk >= end_chunk)
546                         continue;
547                 add_active_range(0, start_chunk, end_chunk);
548                 pfn = max(start_chunk, start_pfn);
549                 for (; pfn <= end_chunk; pfn++)
550                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
551         }
552
553         psw_set_key(PAGE_DEFAULT_KEY);
554
555         free_bootmem_with_active_regions(0, max_pfn);
556         reserve_bootmem(0, PFN_PHYS(start_pfn));
557
558         /*
559          * Reserve the bootmem bitmap itself as well. We do this in two
560          * steps (first step was init_bootmem()) because this catches
561          * the (very unlikely) case of us accidentally initializing the
562          * bootmem allocator with an invalid RAM area.
563          */
564         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size);
565
566 #ifdef CONFIG_BLK_DEV_INITRD
567         if (INITRD_START && INITRD_SIZE) {
568                 if (INITRD_START + INITRD_SIZE <= memory_end) {
569                         reserve_bootmem(INITRD_START, INITRD_SIZE);
570                         initrd_start = INITRD_START;
571                         initrd_end = initrd_start + INITRD_SIZE;
572                 } else {
573                         printk("initrd extends beyond end of memory "
574                                "(0x%08lx > 0x%08lx)\ndisabling initrd\n",
575                                initrd_start + INITRD_SIZE, memory_end);
576                         initrd_start = initrd_end = 0;
577                 }
578         }
579 #endif
580 }
581
582 /*
583  * Setup function called from init/main.c just after the banner
584  * was printed.
585  */
586
587 void __init
588 setup_arch(char **cmdline_p)
589 {
590         /*
591          * print what head.S has found out about the machine
592          */
593 #ifndef CONFIG_64BIT
594         printk((MACHINE_IS_VM) ?
595                "We are running under VM (31 bit mode)\n" :
596                "We are running native (31 bit mode)\n");
597         printk((MACHINE_HAS_IEEE) ?
598                "This machine has an IEEE fpu\n" :
599                "This machine has no IEEE fpu\n");
600 #else /* CONFIG_64BIT */
601         printk((MACHINE_IS_VM) ?
602                "We are running under VM (64 bit mode)\n" :
603                "We are running native (64 bit mode)\n");
604 #endif /* CONFIG_64BIT */
605
606         /* Save unparsed command line copy for /proc/cmdline */
607         strlcpy(saved_command_line, COMMAND_LINE, COMMAND_LINE_SIZE);
608
609         *cmdline_p = COMMAND_LINE;
610         *(*cmdline_p + COMMAND_LINE_SIZE - 1) = '\0';
611
612         ROOT_DEV = Root_RAM0;
613
614         init_mm.start_code = PAGE_OFFSET;
615         init_mm.end_code = (unsigned long) &_etext;
616         init_mm.end_data = (unsigned long) &_edata;
617         init_mm.brk = (unsigned long) &_end;
618
619         memory_end = memory_size;
620
621         if (MACHINE_HAS_MVCOS)
622                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
623         else
624                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
625
626         parse_early_param();
627
628 #ifndef CONFIG_64BIT
629         memory_end &= ~0x400000UL;
630
631         /*
632          * We need some free virtual space to be able to do vmalloc.
633          * On a machine with 2GB memory we make sure that we have at
634          * least 128 MB free space for vmalloc.
635          */
636         if (memory_end > 1920*1024*1024)
637                 memory_end = 1920*1024*1024;
638 #else /* CONFIG_64BIT */
639         memory_end &= ~0x200000UL;
640 #endif /* CONFIG_64BIT */
641
642         setup_memory();
643         setup_resources();
644         setup_lowcore();
645
646         cpu_init();
647         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
648         smp_setup_cpu_possible_map();
649
650         /*
651          * Create kernel page tables and switch to virtual addressing.
652          */
653         paging_init();
654
655         /* Setup default console */
656         conmode_default();
657 }
658
659 void print_cpu_info(struct cpuinfo_S390 *cpuinfo)
660 {
661    printk("cpu %d "
662 #ifdef CONFIG_SMP
663            "phys_idx=%d "
664 #endif
665            "vers=%02X ident=%06X machine=%04X unused=%04X\n",
666            cpuinfo->cpu_nr,
667 #ifdef CONFIG_SMP
668            cpuinfo->cpu_addr,
669 #endif
670            cpuinfo->cpu_id.version,
671            cpuinfo->cpu_id.ident,
672            cpuinfo->cpu_id.machine,
673            cpuinfo->cpu_id.unused);
674 }
675
676 /*
677  * show_cpuinfo - Get information on one CPU for use by procfs.
678  */
679
680 static int show_cpuinfo(struct seq_file *m, void *v)
681 {
682         struct cpuinfo_S390 *cpuinfo;
683         unsigned long n = (unsigned long) v - 1;
684
685         preempt_disable();
686         if (!n) {
687                 seq_printf(m, "vendor_id       : IBM/S390\n"
688                                "# processors    : %i\n"
689                                "bogomips per cpu: %lu.%02lu\n",
690                                num_online_cpus(), loops_per_jiffy/(500000/HZ),
691                                (loops_per_jiffy/(5000/HZ))%100);
692         }
693         if (cpu_online(n)) {
694 #ifdef CONFIG_SMP
695                 if (smp_processor_id() == n)
696                         cpuinfo = &S390_lowcore.cpu_data;
697                 else
698                         cpuinfo = &lowcore_ptr[n]->cpu_data;
699 #else
700                 cpuinfo = &S390_lowcore.cpu_data;
701 #endif
702                 seq_printf(m, "processor %li: "
703                                "version = %02X,  "
704                                "identification = %06X,  "
705                                "machine = %04X\n",
706                                n, cpuinfo->cpu_id.version,
707                                cpuinfo->cpu_id.ident,
708                                cpuinfo->cpu_id.machine);
709         }
710         preempt_enable();
711         return 0;
712 }
713
714 static void *c_start(struct seq_file *m, loff_t *pos)
715 {
716         return *pos < NR_CPUS ? (void *)((unsigned long) *pos + 1) : NULL;
717 }
718 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
719 {
720         ++*pos;
721         return c_start(m, pos);
722 }
723 static void c_stop(struct seq_file *m, void *v)
724 {
725 }
726 struct seq_operations cpuinfo_op = {
727         .start  = c_start,
728         .next   = c_next,
729         .stop   = c_stop,
730         .show   = show_cpuinfo,
731 };
732