[SPARC64]: Sanitize %pstate writes for sun4v.
[linux-2.6] / arch / sparc64 / kernel / setup.c
1 /*  $Id: setup.c,v 1.72 2002/02/09 19:49:30 davem Exp $
2  *  linux/arch/sparc64/kernel/setup.c
3  *
4  *  Copyright (C) 1995,1996  David S. Miller (davem@caip.rutgers.edu)
5  *  Copyright (C) 1997       Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6  */
7
8 #include <linux/errno.h>
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
11 #include <linux/mm.h>
12 #include <linux/stddef.h>
13 #include <linux/unistd.h>
14 #include <linux/ptrace.h>
15 #include <linux/slab.h>
16 #include <asm/smp.h>
17 #include <linux/user.h>
18 #include <linux/a.out.h>
19 #include <linux/tty.h>
20 #include <linux/delay.h>
21 #include <linux/config.h>
22 #include <linux/fs.h>
23 #include <linux/seq_file.h>
24 #include <linux/syscalls.h>
25 #include <linux/kdev_t.h>
26 #include <linux/major.h>
27 #include <linux/string.h>
28 #include <linux/init.h>
29 #include <linux/inet.h>
30 #include <linux/console.h>
31 #include <linux/root_dev.h>
32 #include <linux/interrupt.h>
33 #include <linux/cpu.h>
34 #include <linux/initrd.h>
35
36 #include <asm/system.h>
37 #include <asm/io.h>
38 #include <asm/processor.h>
39 #include <asm/oplib.h>
40 #include <asm/page.h>
41 #include <asm/pgtable.h>
42 #include <asm/idprom.h>
43 #include <asm/head.h>
44 #include <asm/starfire.h>
45 #include <asm/mmu_context.h>
46 #include <asm/timer.h>
47 #include <asm/sections.h>
48 #include <asm/setup.h>
49 #include <asm/mmu.h>
50
51 #ifdef CONFIG_IP_PNP
52 #include <net/ipconfig.h>
53 #endif
54
55 struct screen_info screen_info = {
56         0, 0,                   /* orig-x, orig-y */
57         0,                      /* unused */
58         0,                      /* orig-video-page */
59         0,                      /* orig-video-mode */
60         128,                    /* orig-video-cols */
61         0, 0, 0,                /* unused, ega_bx, unused */
62         54,                     /* orig-video-lines */
63         0,                      /* orig-video-isVGA */
64         16                      /* orig-video-points */
65 };
66
67 /* Typing sync at the prom prompt calls the function pointed to by
68  * the sync callback which I set to the following function.
69  * This should sync all filesystems and return, for now it just
70  * prints out pretty messages and returns.
71  */
72
73 void (*prom_palette)(int);
74 void (*prom_keyboard)(void);
75
76 static void
77 prom_console_write(struct console *con, const char *s, unsigned n)
78 {
79         prom_write(s, n);
80 }
81
82 static struct console prom_console = {
83         .name =         "prom",
84         .write =        prom_console_write,
85         .flags =        CON_CONSDEV | CON_ENABLED,
86         .index =        -1,
87 };
88
89 #define PROM_TRUE       -1
90 #define PROM_FALSE      0
91
92 /* Pretty sick eh? */
93 int prom_callback(long *args)
94 {
95         struct console *cons, *saved_console = NULL;
96         unsigned long flags;
97         char *cmd;
98         extern spinlock_t prom_entry_lock;
99
100         if (!args)
101                 return -1;
102         if (!(cmd = (char *)args[0]))
103                 return -1;
104
105         /*
106          * The callback can be invoked on the cpu that first dropped 
107          * into prom_cmdline after taking the serial interrupt, or on 
108          * a slave processor that was smp_captured() if the 
109          * administrator has done a switch-cpu inside obp. In either 
110          * case, the cpu is marked as in-interrupt. Drop IRQ locks.
111          */
112         irq_exit();
113
114         /* XXX Revisit the locking here someday.  This is a debugging
115          * XXX feature so it isnt all that critical.  -DaveM
116          */
117         local_irq_save(flags);
118
119         spin_unlock(&prom_entry_lock);
120         cons = console_drivers;
121         while (cons) {
122                 unregister_console(cons);
123                 cons->flags &= ~(CON_PRINTBUFFER);
124                 cons->next = saved_console;
125                 saved_console = cons;
126                 cons = console_drivers;
127         }
128         register_console(&prom_console);
129         if (!strcmp(cmd, "sync")) {
130                 prom_printf("PROM `%s' command...\n", cmd);
131                 show_free_areas();
132                 if (current->pid != 0) {
133                         local_irq_enable();
134                         sys_sync();
135                         local_irq_disable();
136                 }
137                 args[2] = 0;
138                 args[args[1] + 3] = -1;
139                 prom_printf("Returning to PROM\n");
140         } else if (!strcmp(cmd, "va>tte-data")) {
141                 unsigned long ctx, va;
142                 unsigned long tte = 0;
143                 long res = PROM_FALSE;
144
145                 ctx = args[3];
146                 va = args[4];
147                 if (ctx) {
148                         /*
149                          * Find process owning ctx, lookup mapping.
150                          */
151                         struct task_struct *p;
152                         struct mm_struct *mm = NULL;
153                         pgd_t *pgdp;
154                         pud_t *pudp;
155                         pmd_t *pmdp;
156                         pte_t *ptep;
157                         pte_t pte;
158
159                         for_each_process(p) {
160                                 mm = p->mm;
161                                 if (CTX_NRBITS(mm->context) == ctx)
162                                         break;
163                         }
164                         if (!mm ||
165                             CTX_NRBITS(mm->context) != ctx)
166                                 goto done;
167
168                         pgdp = pgd_offset(mm, va);
169                         if (pgd_none(*pgdp))
170                                 goto done;
171                         pudp = pud_offset(pgdp, va);
172                         if (pud_none(*pudp))
173                                 goto done;
174                         pmdp = pmd_offset(pudp, va);
175                         if (pmd_none(*pmdp))
176                                 goto done;
177
178                         /* Preemption implicitly disabled by virtue of
179                          * being called from inside OBP.
180                          */
181                         ptep = pte_offset_map(pmdp, va);
182                         pte = *ptep;
183                         if (pte_present(pte)) {
184                                 tte = pte_val(pte);
185                                 res = PROM_TRUE;
186                         }
187                         pte_unmap(ptep);
188                         goto done;
189                 }
190
191                 if ((va >= KERNBASE) && (va < (KERNBASE + (4 * 1024 * 1024)))) {
192                         extern unsigned long sparc64_kern_pri_context;
193
194                         /* Spitfire Errata #32 workaround */
195                         __asm__ __volatile__("stxa      %0, [%1] %2\n\t"
196                                              "flush     %%g6"
197                                              : /* No outputs */
198                                              : "r" (sparc64_kern_pri_context),
199                                                "r" (PRIMARY_CONTEXT),
200                                                "i" (ASI_DMMU));
201
202                         /*
203                          * Locked down tlb entry.
204                          */
205
206                         if (tlb_type == spitfire)
207                                 tte = spitfire_get_dtlb_data(SPITFIRE_HIGHEST_LOCKED_TLBENT);
208                         else if (tlb_type == cheetah || tlb_type == cheetah_plus)
209                                 tte = cheetah_get_ldtlb_data(CHEETAH_HIGHEST_LOCKED_TLBENT);
210
211                         res = PROM_TRUE;
212                         goto done;
213                 }
214
215                 if (va < PGDIR_SIZE) {
216                         /*
217                          * vmalloc or prom_inherited mapping.
218                          */
219                         pgd_t *pgdp;
220                         pud_t *pudp;
221                         pmd_t *pmdp;
222                         pte_t *ptep;
223                         pte_t pte;
224                         int error;
225
226                         if ((va >= LOW_OBP_ADDRESS) && (va < HI_OBP_ADDRESS)) {
227                                 tte = prom_virt_to_phys(va, &error);
228                                 if (!error)
229                                         res = PROM_TRUE;
230                                 goto done;
231                         }
232                         pgdp = pgd_offset_k(va);
233                         if (pgd_none(*pgdp))
234                                 goto done;
235                         pudp = pud_offset(pgdp, va);
236                         if (pud_none(*pudp))
237                                 goto done;
238                         pmdp = pmd_offset(pudp, va);
239                         if (pmd_none(*pmdp))
240                                 goto done;
241
242                         /* Preemption implicitly disabled by virtue of
243                          * being called from inside OBP.
244                          */
245                         ptep = pte_offset_kernel(pmdp, va);
246                         pte = *ptep;
247                         if (pte_present(pte)) {
248                                 tte = pte_val(pte);
249                                 res = PROM_TRUE;
250                         }
251                         goto done;
252                 }
253
254                 if (va < PAGE_OFFSET) {
255                         /*
256                          * No mappings here.
257                          */
258                         goto done;
259                 }
260
261                 if (va & (1UL << 40)) {
262                         /*
263                          * I/O page.
264                          */
265
266                         tte = (__pa(va) & _PAGE_PADDR) |
267                               _PAGE_VALID | _PAGE_SZ4MB |
268                               _PAGE_E | _PAGE_P | _PAGE_W;
269                         res = PROM_TRUE;
270                         goto done;
271                 }
272
273                 /*
274                  * Normal page.
275                  */
276                 tte = (__pa(va) & _PAGE_PADDR) |
277                       _PAGE_VALID | _PAGE_SZ4MB |
278                       _PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W;
279                 res = PROM_TRUE;
280
281         done:
282                 if (res == PROM_TRUE) {
283                         args[2] = 3;
284                         args[args[1] + 3] = 0;
285                         args[args[1] + 4] = res;
286                         args[args[1] + 5] = tte;
287                 } else {
288                         args[2] = 2;
289                         args[args[1] + 3] = 0;
290                         args[args[1] + 4] = res;
291                 }
292         } else if (!strcmp(cmd, ".soft1")) {
293                 unsigned long tte;
294
295                 tte = args[3];
296                 prom_printf("%lx:\"%s%s%s%s%s\" ",
297                             (tte & _PAGE_SOFT) >> 7,
298                             tte & _PAGE_MODIFIED ? "M" : "-",
299                             tte & _PAGE_ACCESSED ? "A" : "-",
300                             tte & _PAGE_READ     ? "W" : "-",
301                             tte & _PAGE_WRITE    ? "R" : "-",
302                             tte & _PAGE_PRESENT  ? "P" : "-");
303
304                 args[2] = 2;
305                 args[args[1] + 3] = 0;
306                 args[args[1] + 4] = PROM_TRUE;
307         } else if (!strcmp(cmd, ".soft2")) {
308                 unsigned long tte;
309
310                 tte = args[3];
311                 prom_printf("%lx ", (tte & 0x07FC000000000000UL) >> 50);
312
313                 args[2] = 2;
314                 args[args[1] + 3] = 0;
315                 args[args[1] + 4] = PROM_TRUE;
316         } else {
317                 prom_printf("unknown PROM `%s' command...\n", cmd);
318         }
319         unregister_console(&prom_console);
320         while (saved_console) {
321                 cons = saved_console;
322                 saved_console = cons->next;
323                 register_console(cons);
324         }
325         spin_lock(&prom_entry_lock);
326         local_irq_restore(flags);
327
328         /*
329          * Restore in-interrupt status for a resume from obp.
330          */
331         irq_enter();
332         return 0;
333 }
334
335 unsigned int boot_flags = 0;
336 #define BOOTME_DEBUG  0x1
337 #define BOOTME_SINGLE 0x2
338
339 /* Exported for mm/init.c:paging_init. */
340 unsigned long cmdline_memory_size = 0;
341
342 static struct console prom_debug_console = {
343         .name =         "debug",
344         .write =        prom_console_write,
345         .flags =        CON_PRINTBUFFER,
346         .index =        -1,
347 };
348
349 /* XXX Implement this at some point... */
350 void kernel_enter_debugger(void)
351 {
352 }
353
354 int obp_system_intr(void)
355 {
356         if (boot_flags & BOOTME_DEBUG) {
357                 printk("OBP: system interrupted\n");
358                 prom_halt();
359                 return 1;
360         }
361         return 0;
362 }
363
364 /* 
365  * Process kernel command line switches that are specific to the
366  * SPARC or that require special low-level processing.
367  */
368 static void __init process_switch(char c)
369 {
370         switch (c) {
371         case 'd':
372                 boot_flags |= BOOTME_DEBUG;
373                 break;
374         case 's':
375                 boot_flags |= BOOTME_SINGLE;
376                 break;
377         case 'h':
378                 prom_printf("boot_flags_init: Halt!\n");
379                 prom_halt();
380                 break;
381         case 'p':
382                 /* Use PROM debug console. */
383                 register_console(&prom_debug_console);
384                 break;
385         case 'P':
386                 /* Force UltraSPARC-III P-Cache on. */
387                 if (tlb_type != cheetah) {
388                         printk("BOOT: Ignoring P-Cache force option.\n");
389                         break;
390                 }
391                 cheetah_pcache_forced_on = 1;
392                 add_taint(TAINT_MACHINE_CHECK);
393                 cheetah_enable_pcache();
394                 break;
395
396         default:
397                 printk("Unknown boot switch (-%c)\n", c);
398                 break;
399         }
400 }
401
402 static void __init process_console(char *commands)
403 {
404         serial_console = 0;
405         commands += 8;
406         /* Linux-style serial */
407         if (!strncmp(commands, "ttyS", 4))
408                 serial_console = simple_strtoul(commands + 4, NULL, 10) + 1;
409         else if (!strncmp(commands, "tty", 3)) {
410                 char c = *(commands + 3);
411                 /* Solaris-style serial */
412                 if (c == 'a' || c == 'b') {
413                         serial_console = c - 'a' + 1;
414                         prom_printf ("Using /dev/tty%c as console.\n", c);
415                 }
416                 /* else Linux-style fbcon, not serial */
417         }
418 #if defined(CONFIG_PROM_CONSOLE)
419         if (!strncmp(commands, "prom", 4)) {
420                 char *p;
421
422                 for (p = commands - 8; *p && *p != ' '; p++)
423                         *p = ' ';
424                 conswitchp = &prom_con;
425         }
426 #endif
427 }
428
429 static void __init boot_flags_init(char *commands)
430 {
431         while (*commands) {
432                 /* Move to the start of the next "argument". */
433                 while (*commands && *commands == ' ')
434                         commands++;
435
436                 /* Process any command switches, otherwise skip it. */
437                 if (*commands == '\0')
438                         break;
439                 if (*commands == '-') {
440                         commands++;
441                         while (*commands && *commands != ' ')
442                                 process_switch(*commands++);
443                         continue;
444                 }
445                 if (!strncmp(commands, "console=", 8)) {
446                         process_console(commands);
447                 } else if (!strncmp(commands, "mem=", 4)) {
448                         /*
449                          * "mem=XXX[kKmM]" overrides the PROM-reported
450                          * memory size.
451                          */
452                         cmdline_memory_size = simple_strtoul(commands + 4,
453                                                              &commands, 0);
454                         if (*commands == 'K' || *commands == 'k') {
455                                 cmdline_memory_size <<= 10;
456                                 commands++;
457                         } else if (*commands=='M' || *commands=='m') {
458                                 cmdline_memory_size <<= 20;
459                                 commands++;
460                         }
461                 }
462                 while (*commands && *commands != ' ')
463                         commands++;
464         }
465 }
466
467 extern void panic_setup(char *, int *);
468
469 extern unsigned short root_flags;
470 extern unsigned short root_dev;
471 extern unsigned short ram_flags;
472 #define RAMDISK_IMAGE_START_MASK        0x07FF
473 #define RAMDISK_PROMPT_FLAG             0x8000
474 #define RAMDISK_LOAD_FLAG               0x4000
475
476 extern int root_mountflags;
477
478 char reboot_command[COMMAND_LINE_SIZE];
479
480 static struct pt_regs fake_swapper_regs = { { 0, }, 0, 0, 0, 0 };
481
482 void register_prom_callbacks(void)
483 {
484         prom_setcallback(prom_callback);
485         prom_feval(": linux-va>tte-data 2 \" va>tte-data\" $callback drop ; "
486                    "' linux-va>tte-data to va>tte-data");
487         prom_feval(": linux-.soft1 1 \" .soft1\" $callback 2drop ; "
488                    "' linux-.soft1 to .soft1");
489         prom_feval(": linux-.soft2 1 \" .soft2\" $callback 2drop ; "
490                    "' linux-.soft2 to .soft2");
491 }
492
493 static void __init per_cpu_patch(void)
494 {
495 #ifdef CONFIG_SMP
496         struct cpuid_patch_entry *p;
497         unsigned long ver;
498         int is_jbus;
499
500         if (tlb_type == spitfire && !this_is_starfire)
501                 return;
502
503         __asm__ ("rdpr %%ver, %0" : "=r" (ver));
504         is_jbus = ((ver >> 32) == __JALAPENO_ID ||
505                    (ver >> 32) == __SERRANO_ID);
506
507         p = &__cpuid_patch;
508         while (p < &__cpuid_patch_end) {
509                 unsigned long addr = p->addr;
510                 unsigned int *insns;
511
512                 switch (tlb_type) {
513                 case spitfire:
514                         insns = &p->starfire[0];
515                         break;
516                 case cheetah:
517                 case cheetah_plus:
518                         if (is_jbus)
519                                 insns = &p->cheetah_jbus[0];
520                         else
521                                 insns = &p->cheetah_safari[0];
522                         break;
523                 case hypervisor:
524                         insns = &p->sun4v[0];
525                         break;
526                 default:
527                         prom_printf("Unknown cpu type, halting.\n");
528                         prom_halt();
529                 };
530
531                 *(unsigned int *) (addr +  0) = insns[0];
532                 __asm__ __volatile__("flush     %0" : : "r" (addr +  0));
533
534                 *(unsigned int *) (addr +  4) = insns[1];
535                 __asm__ __volatile__("flush     %0" : : "r" (addr +  4));
536
537                 *(unsigned int *) (addr +  8) = insns[2];
538                 __asm__ __volatile__("flush     %0" : : "r" (addr +  8));
539
540                 *(unsigned int *) (addr + 12) = insns[3];
541                 __asm__ __volatile__("flush     %0" : : "r" (addr + 12));
542
543                 p++;
544         }
545 #endif
546 }
547
548 static void __init gl_patch(void)
549 {
550         struct gl_1insn_patch_entry *p1;
551         struct gl_2insn_patch_entry *p2;
552
553         if (tlb_type != hypervisor)
554                 return;
555
556         p1 = &__gl_1insn_patch;
557         while (p1 < &__gl_1insn_patch_end) {
558                 unsigned long addr = p1->addr;
559
560                 *(unsigned int *) (addr +  0) = p1->insn;
561                 __asm__ __volatile__("flush     %0" : : "r" (addr +  0));
562
563                 p1++;
564         }
565
566         p2 = &__gl_2insn_patch;
567         while (p2 < &__gl_2insn_patch_end) {
568                 unsigned long addr = p2->addr;
569
570                 *(unsigned int *) (addr +  0) = p2->insns[0];
571                 __asm__ __volatile__("flush     %0" : : "r" (addr +  0));
572
573                 *(unsigned int *) (addr +  3) = p2->insns[1];
574                 __asm__ __volatile__("flush     %0" : : "r" (addr +  4));
575
576                 p2++;
577         }
578 }
579
580 void __init setup_arch(char **cmdline_p)
581 {
582         /* Initialize PROM console and command line. */
583         *cmdline_p = prom_getbootargs();
584         strcpy(saved_command_line, *cmdline_p);
585
586         printk("ARCH: SUN4U\n");
587
588 #ifdef CONFIG_DUMMY_CONSOLE
589         conswitchp = &dummy_con;
590 #elif defined(CONFIG_PROM_CONSOLE)
591         conswitchp = &prom_con;
592 #endif
593
594         /* Work out if we are starfire early on */
595         check_if_starfire();
596
597         /* Now we know enough to patch the get_cpuid sequences
598          * used by trap code.
599          */
600         per_cpu_patch();
601
602         gl_patch();
603
604         boot_flags_init(*cmdline_p);
605
606         idprom_init();
607
608         if (!root_flags)
609                 root_mountflags &= ~MS_RDONLY;
610         ROOT_DEV = old_decode_dev(root_dev);
611 #ifdef CONFIG_BLK_DEV_INITRD
612         rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
613         rd_prompt = ((ram_flags & RAMDISK_PROMPT_FLAG) != 0);
614         rd_doload = ((ram_flags & RAMDISK_LOAD_FLAG) != 0);     
615 #endif
616
617         task_thread_info(&init_task)->kregs = &fake_swapper_regs;
618
619 #ifdef CONFIG_IP_PNP
620         if (!ic_set_manually) {
621                 int chosen = prom_finddevice ("/chosen");
622                 u32 cl, sv, gw;
623                 
624                 cl = prom_getintdefault (chosen, "client-ip", 0);
625                 sv = prom_getintdefault (chosen, "server-ip", 0);
626                 gw = prom_getintdefault (chosen, "gateway-ip", 0);
627                 if (cl && sv) {
628                         ic_myaddr = cl;
629                         ic_servaddr = sv;
630                         if (gw)
631                                 ic_gateway = gw;
632 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_RARP)
633                         ic_proto_enabled = 0;
634 #endif
635                 }
636         }
637 #endif
638
639         smp_setup_cpu_possible_map();
640
641         paging_init();
642
643         /* Get boot processor trap_block[] setup.  */
644         init_cur_cpu_trap();
645 }
646
647 static int __init set_preferred_console(void)
648 {
649         int idev, odev;
650
651         /* The user has requested a console so this is already set up. */
652         if (serial_console >= 0)
653                 return -EBUSY;
654
655         idev = prom_query_input_device();
656         odev = prom_query_output_device();
657         if (idev == PROMDEV_IKBD && odev == PROMDEV_OSCREEN) {
658                 serial_console = 0;
659         } else if (idev == PROMDEV_ITTYA && odev == PROMDEV_OTTYA) {
660                 serial_console = 1;
661         } else if (idev == PROMDEV_ITTYB && odev == PROMDEV_OTTYB) {
662                 serial_console = 2;
663         } else if (idev == PROMDEV_IRSC && odev == PROMDEV_ORSC) {
664                 serial_console = 3;
665         } else {
666                 prom_printf("Inconsistent console: "
667                             "input %d, output %d\n",
668                             idev, odev);
669                 prom_halt();
670         }
671
672         if (serial_console)
673                 return add_preferred_console("ttyS", serial_console - 1, NULL);
674
675         return -ENODEV;
676 }
677 console_initcall(set_preferred_console);
678
679 /* BUFFER is PAGE_SIZE bytes long. */
680
681 extern char *sparc_cpu_type;
682 extern char *sparc_fpu_type;
683
684 extern void smp_info(struct seq_file *);
685 extern void smp_bogo(struct seq_file *);
686 extern void mmu_info(struct seq_file *);
687
688 unsigned int dcache_parity_tl1_occurred;
689 unsigned int icache_parity_tl1_occurred;
690
691 static int ncpus_probed;
692
693 static int show_cpuinfo(struct seq_file *m, void *__unused)
694 {
695         seq_printf(m, 
696                    "cpu\t\t: %s\n"
697                    "fpu\t\t: %s\n"
698                    "promlib\t\t: Version 3 Revision %d\n"
699                    "prom\t\t: %d.%d.%d\n"
700                    "type\t\t: sun4u\n"
701                    "ncpus probed\t: %d\n"
702                    "ncpus active\t: %d\n"
703                    "D$ parity tl1\t: %u\n"
704                    "I$ parity tl1\t: %u\n"
705 #ifndef CONFIG_SMP
706                    "Cpu0Bogo\t: %lu.%02lu\n"
707                    "Cpu0ClkTck\t: %016lx\n"
708 #endif
709                    ,
710                    sparc_cpu_type,
711                    sparc_fpu_type,
712                    prom_rev,
713                    prom_prev >> 16,
714                    (prom_prev >> 8) & 0xff,
715                    prom_prev & 0xff,
716                    ncpus_probed,
717                    num_online_cpus(),
718                    dcache_parity_tl1_occurred,
719                    icache_parity_tl1_occurred
720 #ifndef CONFIG_SMP
721                    , cpu_data(0).udelay_val/(500000/HZ),
722                    (cpu_data(0).udelay_val/(5000/HZ)) % 100,
723                    cpu_data(0).clock_tick
724 #endif
725                 );
726 #ifdef CONFIG_SMP
727         smp_bogo(m);
728 #endif
729         mmu_info(m);
730 #ifdef CONFIG_SMP
731         smp_info(m);
732 #endif
733         return 0;
734 }
735
736 static void *c_start(struct seq_file *m, loff_t *pos)
737 {
738         /* The pointer we are returning is arbitrary,
739          * it just has to be non-NULL and not IS_ERR
740          * in the success case.
741          */
742         return *pos == 0 ? &c_start : NULL;
743 }
744
745 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
746 {
747         ++*pos;
748         return c_start(m, pos);
749 }
750
751 static void c_stop(struct seq_file *m, void *v)
752 {
753 }
754
755 struct seq_operations cpuinfo_op = {
756         .start =c_start,
757         .next = c_next,
758         .stop = c_stop,
759         .show = show_cpuinfo,
760 };
761
762 extern int stop_a_enabled;
763
764 void sun_do_break(void)
765 {
766         if (!stop_a_enabled)
767                 return;
768
769         prom_printf("\n");
770         flush_user_windows();
771
772         prom_cmdline();
773 }
774
775 int serial_console = -1;
776 int stop_a_enabled = 1;
777
778 static int __init topology_init(void)
779 {
780         int i, err;
781
782         err = -ENOMEM;
783
784         /* Count the number of physically present processors in
785          * the machine, even on uniprocessor, so that /proc/cpuinfo
786          * output is consistent with 2.4.x
787          */
788         ncpus_probed = 0;
789         while (!cpu_find_by_instance(ncpus_probed, NULL, NULL))
790                 ncpus_probed++;
791
792         for (i = 0; i < NR_CPUS; i++) {
793                 if (cpu_possible(i)) {
794                         struct cpu *p = kmalloc(sizeof(*p), GFP_KERNEL);
795
796                         if (p) {
797                                 memset(p, 0, sizeof(*p));
798                                 register_cpu(p, i, NULL);
799                                 err = 0;
800                         }
801                 }
802         }
803
804         return err;
805 }
806
807 subsys_initcall(topology_init);