xref: /linux/arch/xtensa/kernel/setup.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * arch/xtensa/kernel/setup.c
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 1995  Linus Torvalds
9  * Copyright (C) 2001 - 2005  Tensilica Inc.
10  *
11  * Chris Zankel	<chris@zankel.net>
12  * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
13  * Kevin Chea
14  * Marc Gauthier<marc@tensilica.com> <marc@alumni.uwaterloo.ca>
15  */
16 
17 #include <linux/errno.h>
18 #include <linux/init.h>
19 #include <linux/mm.h>
20 #include <linux/proc_fs.h>
21 #include <linux/screen_info.h>
22 #include <linux/bootmem.h>
23 #include <linux/kernel.h>
24 #include <linux/percpu.h>
25 #include <linux/clk-provider.h>
26 #include <linux/cpu.h>
27 #include <linux/of_fdt.h>
28 #include <linux/of_platform.h>
29 
30 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
31 # include <linux/console.h>
32 #endif
33 
34 #ifdef CONFIG_RTC
35 # include <linux/timex.h>
36 #endif
37 
38 #ifdef CONFIG_PROC_FS
39 # include <linux/seq_file.h>
40 #endif
41 
42 #include <asm/bootparam.h>
43 #include <asm/mmu_context.h>
44 #include <asm/pgtable.h>
45 #include <asm/processor.h>
46 #include <asm/timex.h>
47 #include <asm/platform.h>
48 #include <asm/page.h>
49 #include <asm/setup.h>
50 #include <asm/param.h>
51 #include <asm/traps.h>
52 #include <asm/smp.h>
53 #include <asm/sysmem.h>
54 
55 #include <platform/hardware.h>
56 
57 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
58 struct screen_info screen_info = { 0, 24, 0, 0, 0, 80, 0, 0, 0, 24, 1, 16};
59 #endif
60 
61 #ifdef CONFIG_BLK_DEV_FD
62 extern struct fd_ops no_fd_ops;
63 struct fd_ops *fd_ops;
64 #endif
65 
66 extern struct rtc_ops no_rtc_ops;
67 struct rtc_ops *rtc_ops;
68 
69 #ifdef CONFIG_BLK_DEV_INITRD
70 extern unsigned long initrd_start;
71 extern unsigned long initrd_end;
72 int initrd_is_mapped = 0;
73 extern int initrd_below_start_ok;
74 #endif
75 
76 #ifdef CONFIG_OF
77 void *dtb_start = __dtb_start;
78 #endif
79 
80 unsigned char aux_device_present;
81 extern unsigned long loops_per_jiffy;
82 
83 /* Command line specified as configuration option. */
84 
85 static char __initdata command_line[COMMAND_LINE_SIZE];
86 
87 #ifdef CONFIG_CMDLINE_BOOL
88 static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
89 #endif
90 
91 /*
92  * Boot parameter parsing.
93  *
94  * The Xtensa port uses a list of variable-sized tags to pass data to
95  * the kernel. The first tag must be a BP_TAG_FIRST tag for the list
96  * to be recognised. The list is terminated with a zero-sized
97  * BP_TAG_LAST tag.
98  */
99 
100 typedef struct tagtable {
101 	u32 tag;
102 	int (*parse)(const bp_tag_t*);
103 } tagtable_t;
104 
105 #define __tagtable(tag, fn) static tagtable_t __tagtable_##fn 		\
106 	__attribute__((used, section(".taglist"))) = { tag, fn }
107 
108 /* parse current tag */
109 
110 static int __init parse_tag_mem(const bp_tag_t *tag)
111 {
112 	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
113 
114 	if (mi->type != MEMORY_TYPE_CONVENTIONAL)
115 		return -1;
116 
117 	return add_sysmem_bank(mi->start, mi->end);
118 }
119 
120 __tagtable(BP_TAG_MEMORY, parse_tag_mem);
121 
122 #ifdef CONFIG_BLK_DEV_INITRD
123 
124 static int __init parse_tag_initrd(const bp_tag_t* tag)
125 {
126 	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
127 
128 	initrd_start = (unsigned long)__va(mi->start);
129 	initrd_end = (unsigned long)__va(mi->end);
130 
131 	return 0;
132 }
133 
134 __tagtable(BP_TAG_INITRD, parse_tag_initrd);
135 
136 #ifdef CONFIG_OF
137 
138 static int __init parse_tag_fdt(const bp_tag_t *tag)
139 {
140 	dtb_start = __va(tag->data[0]);
141 	return 0;
142 }
143 
144 __tagtable(BP_TAG_FDT, parse_tag_fdt);
145 
146 #endif /* CONFIG_OF */
147 
148 #endif /* CONFIG_BLK_DEV_INITRD */
149 
150 static int __init parse_tag_cmdline(const bp_tag_t* tag)
151 {
152 	strlcpy(command_line, (char *)(tag->data), COMMAND_LINE_SIZE);
153 	return 0;
154 }
155 
156 __tagtable(BP_TAG_COMMAND_LINE, parse_tag_cmdline);
157 
158 static int __init parse_bootparam(const bp_tag_t* tag)
159 {
160 	extern tagtable_t __tagtable_begin, __tagtable_end;
161 	tagtable_t *t;
162 
163 	/* Boot parameters must start with a BP_TAG_FIRST tag. */
164 
165 	if (tag->id != BP_TAG_FIRST) {
166 		printk(KERN_WARNING "Invalid boot parameters!\n");
167 		return 0;
168 	}
169 
170 	tag = (bp_tag_t*)((unsigned long)tag + sizeof(bp_tag_t) + tag->size);
171 
172 	/* Parse all tags. */
173 
174 	while (tag != NULL && tag->id != BP_TAG_LAST) {
175 	 	for (t = &__tagtable_begin; t < &__tagtable_end; t++) {
176 			if (tag->id == t->tag) {
177 				t->parse(tag);
178 				break;
179 			}
180 		}
181 		if (t == &__tagtable_end)
182 			printk(KERN_WARNING "Ignoring tag "
183 			       "0x%08x\n", tag->id);
184 		tag = (bp_tag_t*)((unsigned long)(tag + 1) + tag->size);
185 	}
186 
187 	return 0;
188 }
189 
190 #ifdef CONFIG_OF
191 bool __initdata dt_memory_scan = false;
192 
193 #if !XCHAL_HAVE_PTP_MMU || XCHAL_HAVE_SPANNING_WAY
194 unsigned long xtensa_kio_paddr = XCHAL_KIO_DEFAULT_PADDR;
195 EXPORT_SYMBOL(xtensa_kio_paddr);
196 
197 static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
198 		int depth, void *data)
199 {
200 	const __be32 *ranges;
201 	int len;
202 
203 	if (depth > 1)
204 		return 0;
205 
206 	if (!of_flat_dt_is_compatible(node, "simple-bus"))
207 		return 0;
208 
209 	ranges = of_get_flat_dt_prop(node, "ranges", &len);
210 	if (!ranges)
211 		return 1;
212 	if (len == 0)
213 		return 1;
214 
215 	xtensa_kio_paddr = of_read_ulong(ranges+1, 1);
216 	/* round down to nearest 256MB boundary */
217 	xtensa_kio_paddr &= 0xf0000000;
218 
219 	return 1;
220 }
221 #else
222 static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
223 		int depth, void *data)
224 {
225 	return 1;
226 }
227 #endif
228 
229 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
230 {
231 	if (!dt_memory_scan)
232 		return;
233 
234 	size &= PAGE_MASK;
235 	add_sysmem_bank(base, base + size);
236 }
237 
238 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
239 {
240 	return __alloc_bootmem(size, align, 0);
241 }
242 
243 void __init early_init_devtree(void *params)
244 {
245 	if (sysmem.nr_banks == 0)
246 		dt_memory_scan = true;
247 
248 	early_init_dt_scan(params);
249 	of_scan_flat_dt(xtensa_dt_io_area, NULL);
250 
251 	if (!command_line[0])
252 		strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
253 }
254 
255 static int __init xtensa_device_probe(void)
256 {
257 	of_clk_init(NULL);
258 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
259 	return 0;
260 }
261 
262 device_initcall(xtensa_device_probe);
263 
264 #endif /* CONFIG_OF */
265 
266 /*
267  * Initialize architecture. (Early stage)
268  */
269 
270 void __init init_arch(bp_tag_t *bp_start)
271 {
272 	/* Parse boot parameters */
273 
274 	if (bp_start)
275 		parse_bootparam(bp_start);
276 
277 #ifdef CONFIG_OF
278 	early_init_devtree(dtb_start);
279 #endif
280 
281 	if (sysmem.nr_banks == 0) {
282 		add_sysmem_bank(PLATFORM_DEFAULT_MEM_START,
283 				PLATFORM_DEFAULT_MEM_START +
284 				PLATFORM_DEFAULT_MEM_SIZE);
285 	}
286 
287 #ifdef CONFIG_CMDLINE_BOOL
288 	if (!command_line[0])
289 		strlcpy(command_line, default_command_line, COMMAND_LINE_SIZE);
290 #endif
291 
292 	/* Early hook for platforms */
293 
294 	platform_init(bp_start);
295 
296 	/* Initialize MMU. */
297 
298 	init_mmu();
299 }
300 
301 /*
302  * Initialize system. Setup memory and reserve regions.
303  */
304 
305 extern char _end;
306 extern char _stext;
307 extern char _WindowVectors_text_start;
308 extern char _WindowVectors_text_end;
309 extern char _DebugInterruptVector_literal_start;
310 extern char _DebugInterruptVector_text_end;
311 extern char _KernelExceptionVector_literal_start;
312 extern char _KernelExceptionVector_text_end;
313 extern char _UserExceptionVector_literal_start;
314 extern char _UserExceptionVector_text_end;
315 extern char _DoubleExceptionVector_literal_start;
316 extern char _DoubleExceptionVector_text_end;
317 #if XCHAL_EXCM_LEVEL >= 2
318 extern char _Level2InterruptVector_text_start;
319 extern char _Level2InterruptVector_text_end;
320 #endif
321 #if XCHAL_EXCM_LEVEL >= 3
322 extern char _Level3InterruptVector_text_start;
323 extern char _Level3InterruptVector_text_end;
324 #endif
325 #if XCHAL_EXCM_LEVEL >= 4
326 extern char _Level4InterruptVector_text_start;
327 extern char _Level4InterruptVector_text_end;
328 #endif
329 #if XCHAL_EXCM_LEVEL >= 5
330 extern char _Level5InterruptVector_text_start;
331 extern char _Level5InterruptVector_text_end;
332 #endif
333 #if XCHAL_EXCM_LEVEL >= 6
334 extern char _Level6InterruptVector_text_start;
335 extern char _Level6InterruptVector_text_end;
336 #endif
337 
338 
339 
340 #ifdef CONFIG_S32C1I_SELFTEST
341 #if XCHAL_HAVE_S32C1I
342 
343 static int __initdata rcw_word, rcw_probe_pc, rcw_exc;
344 
345 /*
346  * Basic atomic compare-and-swap, that records PC of S32C1I for probing.
347  *
348  * If *v == cmp, set *v = set.  Return previous *v.
349  */
350 static inline int probed_compare_swap(int *v, int cmp, int set)
351 {
352 	int tmp;
353 
354 	__asm__ __volatile__(
355 			"	movi	%1, 1f\n"
356 			"	s32i	%1, %4, 0\n"
357 			"	wsr	%2, scompare1\n"
358 			"1:	s32c1i	%0, %3, 0\n"
359 			: "=a" (set), "=&a" (tmp)
360 			: "a" (cmp), "a" (v), "a" (&rcw_probe_pc), "0" (set)
361 			: "memory"
362 			);
363 	return set;
364 }
365 
366 /* Handle probed exception */
367 
368 static void __init do_probed_exception(struct pt_regs *regs,
369 		unsigned long exccause)
370 {
371 	if (regs->pc == rcw_probe_pc) {	/* exception on s32c1i ? */
372 		regs->pc += 3;		/* skip the s32c1i instruction */
373 		rcw_exc = exccause;
374 	} else {
375 		do_unhandled(regs, exccause);
376 	}
377 }
378 
379 /* Simple test of S32C1I (soc bringup assist) */
380 
381 static int __init check_s32c1i(void)
382 {
383 	int n, cause1, cause2;
384 	void *handbus, *handdata, *handaddr; /* temporarily saved handlers */
385 
386 	rcw_probe_pc = 0;
387 	handbus  = trap_set_handler(EXCCAUSE_LOAD_STORE_ERROR,
388 			do_probed_exception);
389 	handdata = trap_set_handler(EXCCAUSE_LOAD_STORE_DATA_ERROR,
390 			do_probed_exception);
391 	handaddr = trap_set_handler(EXCCAUSE_LOAD_STORE_ADDR_ERROR,
392 			do_probed_exception);
393 
394 	/* First try an S32C1I that does not store: */
395 	rcw_exc = 0;
396 	rcw_word = 1;
397 	n = probed_compare_swap(&rcw_word, 0, 2);
398 	cause1 = rcw_exc;
399 
400 	/* took exception? */
401 	if (cause1 != 0) {
402 		/* unclean exception? */
403 		if (n != 2 || rcw_word != 1)
404 			panic("S32C1I exception error");
405 	} else if (rcw_word != 1 || n != 1) {
406 		panic("S32C1I compare error");
407 	}
408 
409 	/* Then an S32C1I that stores: */
410 	rcw_exc = 0;
411 	rcw_word = 0x1234567;
412 	n = probed_compare_swap(&rcw_word, 0x1234567, 0xabcde);
413 	cause2 = rcw_exc;
414 
415 	if (cause2 != 0) {
416 		/* unclean exception? */
417 		if (n != 0xabcde || rcw_word != 0x1234567)
418 			panic("S32C1I exception error (b)");
419 	} else if (rcw_word != 0xabcde || n != 0x1234567) {
420 		panic("S32C1I store error");
421 	}
422 
423 	/* Verify consistency of exceptions: */
424 	if (cause1 || cause2) {
425 		pr_warn("S32C1I took exception %d, %d\n", cause1, cause2);
426 		/* If emulation of S32C1I upon bus error gets implemented,
427 		   we can get rid of this panic for single core (not SMP) */
428 		panic("S32C1I exceptions not currently supported");
429 	}
430 	if (cause1 != cause2)
431 		panic("inconsistent S32C1I exceptions");
432 
433 	trap_set_handler(EXCCAUSE_LOAD_STORE_ERROR, handbus);
434 	trap_set_handler(EXCCAUSE_LOAD_STORE_DATA_ERROR, handdata);
435 	trap_set_handler(EXCCAUSE_LOAD_STORE_ADDR_ERROR, handaddr);
436 	return 0;
437 }
438 
439 #else /* XCHAL_HAVE_S32C1I */
440 
441 /* This condition should not occur with a commercially deployed processor.
442    Display reminder for early engr test or demo chips / FPGA bitstreams */
443 static int __init check_s32c1i(void)
444 {
445 	pr_warn("Processor configuration lacks atomic compare-and-swap support!\n");
446 	return 0;
447 }
448 
449 #endif /* XCHAL_HAVE_S32C1I */
450 early_initcall(check_s32c1i);
451 #endif /* CONFIG_S32C1I_SELFTEST */
452 
453 
454 void __init setup_arch(char **cmdline_p)
455 {
456 	strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
457 	*cmdline_p = command_line;
458 
459 	/* Reserve some memory regions */
460 
461 #ifdef CONFIG_BLK_DEV_INITRD
462 	if (initrd_start < initrd_end) {
463 		initrd_is_mapped = mem_reserve(__pa(initrd_start),
464 					       __pa(initrd_end), 0) == 0;
465 		initrd_below_start_ok = 1;
466 	} else {
467 		initrd_start = 0;
468 	}
469 #endif
470 
471 	mem_reserve(__pa(&_stext),__pa(&_end), 1);
472 
473 	mem_reserve(__pa(&_WindowVectors_text_start),
474 		    __pa(&_WindowVectors_text_end), 0);
475 
476 	mem_reserve(__pa(&_DebugInterruptVector_literal_start),
477 		    __pa(&_DebugInterruptVector_text_end), 0);
478 
479 	mem_reserve(__pa(&_KernelExceptionVector_literal_start),
480 		    __pa(&_KernelExceptionVector_text_end), 0);
481 
482 	mem_reserve(__pa(&_UserExceptionVector_literal_start),
483 		    __pa(&_UserExceptionVector_text_end), 0);
484 
485 	mem_reserve(__pa(&_DoubleExceptionVector_literal_start),
486 		    __pa(&_DoubleExceptionVector_text_end), 0);
487 
488 #if XCHAL_EXCM_LEVEL >= 2
489 	mem_reserve(__pa(&_Level2InterruptVector_text_start),
490 		    __pa(&_Level2InterruptVector_text_end), 0);
491 #endif
492 #if XCHAL_EXCM_LEVEL >= 3
493 	mem_reserve(__pa(&_Level3InterruptVector_text_start),
494 		    __pa(&_Level3InterruptVector_text_end), 0);
495 #endif
496 #if XCHAL_EXCM_LEVEL >= 4
497 	mem_reserve(__pa(&_Level4InterruptVector_text_start),
498 		    __pa(&_Level4InterruptVector_text_end), 0);
499 #endif
500 #if XCHAL_EXCM_LEVEL >= 5
501 	mem_reserve(__pa(&_Level5InterruptVector_text_start),
502 		    __pa(&_Level5InterruptVector_text_end), 0);
503 #endif
504 #if XCHAL_EXCM_LEVEL >= 6
505 	mem_reserve(__pa(&_Level6InterruptVector_text_start),
506 		    __pa(&_Level6InterruptVector_text_end), 0);
507 #endif
508 
509 	parse_early_param();
510 	bootmem_init();
511 
512 	unflatten_and_copy_device_tree();
513 
514 	platform_setup(cmdline_p);
515 
516 #ifdef CONFIG_SMP
517 	smp_init_cpus();
518 #endif
519 
520 	paging_init();
521 	zones_init();
522 
523 #ifdef CONFIG_VT
524 # if defined(CONFIG_VGA_CONSOLE)
525 	conswitchp = &vga_con;
526 # elif defined(CONFIG_DUMMY_CONSOLE)
527 	conswitchp = &dummy_con;
528 # endif
529 #endif
530 
531 #ifdef CONFIG_PCI
532 	platform_pcibios_init();
533 #endif
534 }
535 
536 static DEFINE_PER_CPU(struct cpu, cpu_data);
537 
538 static int __init topology_init(void)
539 {
540 	int i;
541 
542 	for_each_possible_cpu(i) {
543 		struct cpu *cpu = &per_cpu(cpu_data, i);
544 		cpu->hotpluggable = !!i;
545 		register_cpu(cpu, i);
546 	}
547 
548 	return 0;
549 }
550 subsys_initcall(topology_init);
551 
552 void machine_restart(char * cmd)
553 {
554 	platform_restart();
555 }
556 
557 void machine_halt(void)
558 {
559 	platform_halt();
560 	while (1);
561 }
562 
563 void machine_power_off(void)
564 {
565 	platform_power_off();
566 	while (1);
567 }
568 #ifdef CONFIG_PROC_FS
569 
570 /*
571  * Display some core information through /proc/cpuinfo.
572  */
573 
574 static int
575 c_show(struct seq_file *f, void *slot)
576 {
577 	/* high-level stuff */
578 	seq_printf(f, "CPU count\t: %u\n"
579 		      "CPU list\t: %*pbl\n"
580 		      "vendor_id\t: Tensilica\n"
581 		      "model\t\t: Xtensa " XCHAL_HW_VERSION_NAME "\n"
582 		      "core ID\t\t: " XCHAL_CORE_ID "\n"
583 		      "build ID\t: 0x%x\n"
584 		      "byte order\t: %s\n"
585 		      "cpu MHz\t\t: %lu.%02lu\n"
586 		      "bogomips\t: %lu.%02lu\n",
587 		      num_online_cpus(),
588 		      cpumask_pr_args(cpu_online_mask),
589 		      XCHAL_BUILD_UNIQUE_ID,
590 		      XCHAL_HAVE_BE ?  "big" : "little",
591 		      ccount_freq/1000000,
592 		      (ccount_freq/10000) % 100,
593 		      loops_per_jiffy/(500000/HZ),
594 		      (loops_per_jiffy/(5000/HZ)) % 100);
595 
596 	seq_printf(f,"flags\t\t: "
597 #if XCHAL_HAVE_NMI
598 		     "nmi "
599 #endif
600 #if XCHAL_HAVE_DEBUG
601 		     "debug "
602 # if XCHAL_HAVE_OCD
603 		     "ocd "
604 # endif
605 #endif
606 #if XCHAL_HAVE_DENSITY
607 	    	     "density "
608 #endif
609 #if XCHAL_HAVE_BOOLEANS
610 		     "boolean "
611 #endif
612 #if XCHAL_HAVE_LOOPS
613 		     "loop "
614 #endif
615 #if XCHAL_HAVE_NSA
616 		     "nsa "
617 #endif
618 #if XCHAL_HAVE_MINMAX
619 		     "minmax "
620 #endif
621 #if XCHAL_HAVE_SEXT
622 		     "sext "
623 #endif
624 #if XCHAL_HAVE_CLAMPS
625 		     "clamps "
626 #endif
627 #if XCHAL_HAVE_MAC16
628 		     "mac16 "
629 #endif
630 #if XCHAL_HAVE_MUL16
631 		     "mul16 "
632 #endif
633 #if XCHAL_HAVE_MUL32
634 		     "mul32 "
635 #endif
636 #if XCHAL_HAVE_MUL32_HIGH
637 		     "mul32h "
638 #endif
639 #if XCHAL_HAVE_FP
640 		     "fpu "
641 #endif
642 #if XCHAL_HAVE_S32C1I
643 		     "s32c1i "
644 #endif
645 		     "\n");
646 
647 	/* Registers. */
648 	seq_printf(f,"physical aregs\t: %d\n"
649 		     "misc regs\t: %d\n"
650 		     "ibreak\t\t: %d\n"
651 		     "dbreak\t\t: %d\n",
652 		     XCHAL_NUM_AREGS,
653 		     XCHAL_NUM_MISC_REGS,
654 		     XCHAL_NUM_IBREAK,
655 		     XCHAL_NUM_DBREAK);
656 
657 
658 	/* Interrupt. */
659 	seq_printf(f,"num ints\t: %d\n"
660 		     "ext ints\t: %d\n"
661 		     "int levels\t: %d\n"
662 		     "timers\t\t: %d\n"
663 		     "debug level\t: %d\n",
664 		     XCHAL_NUM_INTERRUPTS,
665 		     XCHAL_NUM_EXTINTERRUPTS,
666 		     XCHAL_NUM_INTLEVELS,
667 		     XCHAL_NUM_TIMERS,
668 		     XCHAL_DEBUGLEVEL);
669 
670 	/* Cache */
671 	seq_printf(f,"icache line size: %d\n"
672 		     "icache ways\t: %d\n"
673 		     "icache size\t: %d\n"
674 		     "icache flags\t: "
675 #if XCHAL_ICACHE_LINE_LOCKABLE
676 		     "lock "
677 #endif
678 		     "\n"
679 		     "dcache line size: %d\n"
680 		     "dcache ways\t: %d\n"
681 		     "dcache size\t: %d\n"
682 		     "dcache flags\t: "
683 #if XCHAL_DCACHE_IS_WRITEBACK
684 		     "writeback "
685 #endif
686 #if XCHAL_DCACHE_LINE_LOCKABLE
687 		     "lock "
688 #endif
689 		     "\n",
690 		     XCHAL_ICACHE_LINESIZE,
691 		     XCHAL_ICACHE_WAYS,
692 		     XCHAL_ICACHE_SIZE,
693 		     XCHAL_DCACHE_LINESIZE,
694 		     XCHAL_DCACHE_WAYS,
695 		     XCHAL_DCACHE_SIZE);
696 
697 	return 0;
698 }
699 
700 /*
701  * We show only CPU #0 info.
702  */
703 static void *
704 c_start(struct seq_file *f, loff_t *pos)
705 {
706 	return (*pos == 0) ? (void *)1 : NULL;
707 }
708 
709 static void *
710 c_next(struct seq_file *f, void *v, loff_t *pos)
711 {
712 	return NULL;
713 }
714 
715 static void
716 c_stop(struct seq_file *f, void *v)
717 {
718 }
719 
720 const struct seq_operations cpuinfo_op =
721 {
722 	.start	= c_start,
723 	.next	= c_next,
724 	.stop	= c_stop,
725 	.show	= c_show,
726 };
727 
728 #endif /* CONFIG_PROC_FS */
729