xref: /openbmc/linux/arch/xtensa/kernel/setup.c (revision d2f4a190)
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  * Copyright (C) 2014 - 2016  Cadence Design Systems Inc.
11  *
12  * Chris Zankel	<chris@zankel.net>
13  * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
14  * Kevin Chea
15  * Marc Gauthier<marc@tensilica.com> <marc@alumni.uwaterloo.ca>
16  */
17 
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/mm.h>
21 #include <linux/proc_fs.h>
22 #include <linux/screen_info.h>
23 #include <linux/kernel.h>
24 #include <linux/percpu.h>
25 #include <linux/cpu.h>
26 #include <linux/of.h>
27 #include <linux/of_fdt.h>
28 
29 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
30 # include <linux/console.h>
31 #endif
32 
33 #ifdef CONFIG_PROC_FS
34 # include <linux/seq_file.h>
35 #endif
36 
37 #include <asm/bootparam.h>
38 #include <asm/kasan.h>
39 #include <asm/mmu_context.h>
40 #include <asm/page.h>
41 #include <asm/param.h>
42 #include <asm/platform.h>
43 #include <asm/processor.h>
44 #include <asm/sections.h>
45 #include <asm/setup.h>
46 #include <asm/smp.h>
47 #include <asm/sysmem.h>
48 #include <asm/timex.h>
49 
50 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
51 struct screen_info screen_info = {
52 	.orig_x = 0,
53 	.orig_y = 24,
54 	.orig_video_cols = 80,
55 	.orig_video_lines = 24,
56 	.orig_video_isVGA = 1,
57 	.orig_video_points = 16,
58 };
59 #endif
60 
61 #ifdef CONFIG_BLK_DEV_INITRD
62 extern unsigned long initrd_start;
63 extern unsigned long initrd_end;
64 extern int initrd_below_start_ok;
65 #endif
66 
67 #ifdef CONFIG_USE_OF
68 void *dtb_start = __dtb_start;
69 #endif
70 
71 extern unsigned long loops_per_jiffy;
72 
73 /* Command line specified as configuration option. */
74 
75 static char __initdata command_line[COMMAND_LINE_SIZE];
76 
77 #ifdef CONFIG_CMDLINE_BOOL
78 static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
79 #endif
80 
81 #ifdef CONFIG_PARSE_BOOTPARAM
82 /*
83  * Boot parameter parsing.
84  *
85  * The Xtensa port uses a list of variable-sized tags to pass data to
86  * the kernel. The first tag must be a BP_TAG_FIRST tag for the list
87  * to be recognised. The list is terminated with a zero-sized
88  * BP_TAG_LAST tag.
89  */
90 
91 typedef struct tagtable {
92 	u32 tag;
93 	int (*parse)(const bp_tag_t*);
94 } tagtable_t;
95 
96 #define __tagtable(tag, fn) static tagtable_t __tagtable_##fn 		\
97 	__section(".taglist") __attribute__((used)) = { tag, fn }
98 
99 /* parse current tag */
100 
101 static int __init parse_tag_mem(const bp_tag_t *tag)
102 {
103 	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
104 
105 	if (mi->type != MEMORY_TYPE_CONVENTIONAL)
106 		return -1;
107 
108 	return memblock_add(mi->start, mi->end - mi->start);
109 }
110 
111 __tagtable(BP_TAG_MEMORY, parse_tag_mem);
112 
113 #ifdef CONFIG_BLK_DEV_INITRD
114 
115 static int __init parse_tag_initrd(const bp_tag_t* tag)
116 {
117 	struct bp_meminfo *mi = (struct bp_meminfo *)(tag->data);
118 
119 	initrd_start = (unsigned long)__va(mi->start);
120 	initrd_end = (unsigned long)__va(mi->end);
121 
122 	return 0;
123 }
124 
125 __tagtable(BP_TAG_INITRD, parse_tag_initrd);
126 
127 #endif /* CONFIG_BLK_DEV_INITRD */
128 
129 #ifdef CONFIG_USE_OF
130 
131 static int __init parse_tag_fdt(const bp_tag_t *tag)
132 {
133 	dtb_start = __va(tag->data[0]);
134 	return 0;
135 }
136 
137 __tagtable(BP_TAG_FDT, parse_tag_fdt);
138 
139 #endif /* CONFIG_USE_OF */
140 
141 static int __init parse_tag_cmdline(const bp_tag_t* tag)
142 {
143 	strscpy(command_line, (char *)(tag->data), COMMAND_LINE_SIZE);
144 	return 0;
145 }
146 
147 __tagtable(BP_TAG_COMMAND_LINE, parse_tag_cmdline);
148 
149 static int __init parse_bootparam(const bp_tag_t* tag)
150 {
151 	extern tagtable_t __tagtable_begin, __tagtable_end;
152 	tagtable_t *t;
153 
154 	/* Boot parameters must start with a BP_TAG_FIRST tag. */
155 
156 	if (tag->id != BP_TAG_FIRST) {
157 		pr_warn("Invalid boot parameters!\n");
158 		return 0;
159 	}
160 
161 	tag = (bp_tag_t*)((unsigned long)tag + sizeof(bp_tag_t) + tag->size);
162 
163 	/* Parse all tags. */
164 
165 	while (tag != NULL && tag->id != BP_TAG_LAST) {
166 		for (t = &__tagtable_begin; t < &__tagtable_end; t++) {
167 			if (tag->id == t->tag) {
168 				t->parse(tag);
169 				break;
170 			}
171 		}
172 		if (t == &__tagtable_end)
173 			pr_warn("Ignoring tag 0x%08x\n", tag->id);
174 		tag = (bp_tag_t*)((unsigned long)(tag + 1) + tag->size);
175 	}
176 
177 	return 0;
178 }
179 #else
180 static int __init parse_bootparam(const bp_tag_t *tag)
181 {
182 	pr_info("Ignoring boot parameters at %p\n", tag);
183 	return 0;
184 }
185 #endif
186 
187 #ifdef CONFIG_USE_OF
188 
189 #if !XCHAL_HAVE_PTP_MMU || XCHAL_HAVE_SPANNING_WAY
190 unsigned long xtensa_kio_paddr = XCHAL_KIO_DEFAULT_PADDR;
191 EXPORT_SYMBOL(xtensa_kio_paddr);
192 
193 static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
194 		int depth, void *data)
195 {
196 	const __be32 *ranges;
197 	int len;
198 
199 	if (depth > 1)
200 		return 0;
201 
202 	if (!of_flat_dt_is_compatible(node, "simple-bus"))
203 		return 0;
204 
205 	ranges = of_get_flat_dt_prop(node, "ranges", &len);
206 	if (!ranges)
207 		return 1;
208 	if (len == 0)
209 		return 1;
210 
211 	xtensa_kio_paddr = of_read_ulong(ranges+1, 1);
212 	/* round down to nearest 256MB boundary */
213 	xtensa_kio_paddr &= 0xf0000000;
214 
215 	init_kio();
216 
217 	return 1;
218 }
219 #else
220 static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
221 		int depth, void *data)
222 {
223 	return 1;
224 }
225 #endif
226 
227 void __init early_init_devtree(void *params)
228 {
229 	early_init_dt_scan(params);
230 	of_scan_flat_dt(xtensa_dt_io_area, NULL);
231 
232 	if (!command_line[0])
233 		strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
234 }
235 
236 #endif /* CONFIG_USE_OF */
237 
238 /*
239  * Initialize architecture. (Early stage)
240  */
241 
242 void __init init_arch(bp_tag_t *bp_start)
243 {
244 	/* Initialize MMU. */
245 
246 	init_mmu();
247 
248 	/* Initialize initial KASAN shadow map */
249 
250 	kasan_early_init();
251 
252 	/* Parse boot parameters */
253 
254 	if (bp_start)
255 		parse_bootparam(bp_start);
256 
257 #ifdef CONFIG_USE_OF
258 	early_init_devtree(dtb_start);
259 #endif
260 
261 #ifdef CONFIG_CMDLINE_BOOL
262 	if (!command_line[0])
263 		strscpy(command_line, default_command_line, COMMAND_LINE_SIZE);
264 #endif
265 
266 	/* Early hook for platforms */
267 
268 	platform_init(bp_start);
269 }
270 
271 /*
272  * Initialize system. Setup memory and reserve regions.
273  */
274 
275 static inline int __init_memblock mem_reserve(unsigned long start,
276 					      unsigned long end)
277 {
278 	return memblock_reserve(start, end - start);
279 }
280 
281 void __init setup_arch(char **cmdline_p)
282 {
283 	pr_info("config ID: %08x:%08x\n",
284 		xtensa_get_sr(SREG_EPC), xtensa_get_sr(SREG_EXCSAVE));
285 	if (xtensa_get_sr(SREG_EPC) != XCHAL_HW_CONFIGID0 ||
286 	    xtensa_get_sr(SREG_EXCSAVE) != XCHAL_HW_CONFIGID1)
287 		pr_info("built for config ID: %08x:%08x\n",
288 			XCHAL_HW_CONFIGID0, XCHAL_HW_CONFIGID1);
289 
290 	*cmdline_p = command_line;
291 	platform_setup(cmdline_p);
292 	strscpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
293 
294 	/* Reserve some memory regions */
295 
296 #ifdef CONFIG_BLK_DEV_INITRD
297 	if (initrd_start < initrd_end &&
298 	    !mem_reserve(__pa(initrd_start), __pa(initrd_end)))
299 		initrd_below_start_ok = 1;
300 	else
301 		initrd_start = 0;
302 #endif
303 
304 	mem_reserve(__pa(_stext), __pa(_end));
305 #ifdef CONFIG_XIP_KERNEL
306 	mem_reserve(__pa(_xip_start), __pa(_xip_end));
307 #endif
308 
309 #ifdef CONFIG_VECTORS_ADDR
310 #ifdef SUPPORT_WINDOWED
311 	mem_reserve(__pa(_WindowVectors_text_start),
312 		    __pa(_WindowVectors_text_end));
313 #endif
314 
315 	mem_reserve(__pa(_DebugInterruptVector_text_start),
316 		    __pa(_DebugInterruptVector_text_end));
317 
318 	mem_reserve(__pa(_KernelExceptionVector_text_start),
319 		    __pa(_KernelExceptionVector_text_end));
320 
321 	mem_reserve(__pa(_UserExceptionVector_text_start),
322 		    __pa(_UserExceptionVector_text_end));
323 
324 	mem_reserve(__pa(_DoubleExceptionVector_text_start),
325 		    __pa(_DoubleExceptionVector_text_end));
326 
327 	mem_reserve(__pa(_exception_text_start),
328 		    __pa(_exception_text_end));
329 #if XCHAL_EXCM_LEVEL >= 2
330 	mem_reserve(__pa(_Level2InterruptVector_text_start),
331 		    __pa(_Level2InterruptVector_text_end));
332 #endif
333 #if XCHAL_EXCM_LEVEL >= 3
334 	mem_reserve(__pa(_Level3InterruptVector_text_start),
335 		    __pa(_Level3InterruptVector_text_end));
336 #endif
337 #if XCHAL_EXCM_LEVEL >= 4
338 	mem_reserve(__pa(_Level4InterruptVector_text_start),
339 		    __pa(_Level4InterruptVector_text_end));
340 #endif
341 #if XCHAL_EXCM_LEVEL >= 5
342 	mem_reserve(__pa(_Level5InterruptVector_text_start),
343 		    __pa(_Level5InterruptVector_text_end));
344 #endif
345 #if XCHAL_EXCM_LEVEL >= 6
346 	mem_reserve(__pa(_Level6InterruptVector_text_start),
347 		    __pa(_Level6InterruptVector_text_end));
348 #endif
349 
350 #endif /* CONFIG_VECTORS_ADDR */
351 
352 #ifdef CONFIG_SECONDARY_RESET_VECTOR
353 	mem_reserve(__pa(_SecondaryResetVector_text_start),
354 		    __pa(_SecondaryResetVector_text_end));
355 #endif
356 	parse_early_param();
357 	bootmem_init();
358 	kasan_init();
359 	unflatten_and_copy_device_tree();
360 
361 #ifdef CONFIG_SMP
362 	smp_init_cpus();
363 #endif
364 
365 	paging_init();
366 	zones_init();
367 
368 #ifdef CONFIG_VT
369 # if defined(CONFIG_VGA_CONSOLE)
370 	conswitchp = &vga_con;
371 # endif
372 #endif
373 }
374 
375 static DEFINE_PER_CPU(struct cpu, cpu_data);
376 
377 static int __init topology_init(void)
378 {
379 	int i;
380 
381 	for_each_possible_cpu(i) {
382 		struct cpu *cpu = &per_cpu(cpu_data, i);
383 		cpu->hotpluggable = !!i;
384 		register_cpu(cpu, i);
385 	}
386 
387 	return 0;
388 }
389 subsys_initcall(topology_init);
390 
391 void cpu_reset(void)
392 {
393 #if XCHAL_HAVE_PTP_MMU && IS_ENABLED(CONFIG_MMU)
394 	local_irq_disable();
395 	/*
396 	 * We have full MMU: all autoload ways, ways 7, 8 and 9 of DTLB must
397 	 * be flushed.
398 	 * Way 4 is not currently used by linux.
399 	 * Ways 5 and 6 shall not be touched on MMUv2 as they are hardwired.
400 	 * Way 5 shall be flushed and way 6 shall be set to identity mapping
401 	 * on MMUv3.
402 	 */
403 	local_flush_tlb_all();
404 	invalidate_page_directory();
405 #if XCHAL_HAVE_SPANNING_WAY
406 	/* MMU v3 */
407 	{
408 		unsigned long vaddr = (unsigned long)cpu_reset;
409 		unsigned long paddr = __pa(vaddr);
410 		unsigned long tmpaddr = vaddr + SZ_512M;
411 		unsigned long tmp0, tmp1, tmp2, tmp3;
412 
413 		/*
414 		 * Find a place for the temporary mapping. It must not be
415 		 * in the same 512MB region with vaddr or paddr, otherwise
416 		 * there may be multihit exception either on entry to the
417 		 * temporary mapping, or on entry to the identity mapping.
418 		 * (512MB is the biggest page size supported by TLB.)
419 		 */
420 		while (((tmpaddr ^ paddr) & -SZ_512M) == 0)
421 			tmpaddr += SZ_512M;
422 
423 		/* Invalidate mapping in the selected temporary area */
424 		if (itlb_probe(tmpaddr) & BIT(ITLB_HIT_BIT))
425 			invalidate_itlb_entry(itlb_probe(tmpaddr));
426 		if (itlb_probe(tmpaddr + PAGE_SIZE) & BIT(ITLB_HIT_BIT))
427 			invalidate_itlb_entry(itlb_probe(tmpaddr + PAGE_SIZE));
428 
429 		/*
430 		 * Map two consecutive pages starting at the physical address
431 		 * of this function to the temporary mapping area.
432 		 */
433 		write_itlb_entry(__pte((paddr & PAGE_MASK) |
434 				       _PAGE_HW_VALID |
435 				       _PAGE_HW_EXEC |
436 				       _PAGE_CA_BYPASS),
437 				 tmpaddr & PAGE_MASK);
438 		write_itlb_entry(__pte(((paddr & PAGE_MASK) + PAGE_SIZE) |
439 				       _PAGE_HW_VALID |
440 				       _PAGE_HW_EXEC |
441 				       _PAGE_CA_BYPASS),
442 				 (tmpaddr & PAGE_MASK) + PAGE_SIZE);
443 
444 		/* Reinitialize TLB */
445 		__asm__ __volatile__ ("movi	%0, 1f\n\t"
446 				      "movi	%3, 2f\n\t"
447 				      "add	%0, %0, %4\n\t"
448 				      "add	%3, %3, %5\n\t"
449 				      "jx	%0\n"
450 				      /*
451 				       * No literal, data or stack access
452 				       * below this point
453 				       */
454 				      "1:\n\t"
455 				      /* Initialize *tlbcfg */
456 				      "movi	%0, 0\n\t"
457 				      "wsr	%0, itlbcfg\n\t"
458 				      "wsr	%0, dtlbcfg\n\t"
459 				      /* Invalidate TLB way 5 */
460 				      "movi	%0, 4\n\t"
461 				      "movi	%1, 5\n"
462 				      "1:\n\t"
463 				      "iitlb	%1\n\t"
464 				      "idtlb	%1\n\t"
465 				      "add	%1, %1, %6\n\t"
466 				      "addi	%0, %0, -1\n\t"
467 				      "bnez	%0, 1b\n\t"
468 				      /* Initialize TLB way 6 */
469 				      "movi	%0, 7\n\t"
470 				      "addi	%1, %9, 3\n\t"
471 				      "addi	%2, %9, 6\n"
472 				      "1:\n\t"
473 				      "witlb	%1, %2\n\t"
474 				      "wdtlb	%1, %2\n\t"
475 				      "add	%1, %1, %7\n\t"
476 				      "add	%2, %2, %7\n\t"
477 				      "addi	%0, %0, -1\n\t"
478 				      "bnez	%0, 1b\n\t"
479 				      "isync\n\t"
480 				      /* Jump to identity mapping */
481 				      "jx	%3\n"
482 				      "2:\n\t"
483 				      /* Complete way 6 initialization */
484 				      "witlb	%1, %2\n\t"
485 				      "wdtlb	%1, %2\n\t"
486 				      /* Invalidate temporary mapping */
487 				      "sub	%0, %9, %7\n\t"
488 				      "iitlb	%0\n\t"
489 				      "add	%0, %0, %8\n\t"
490 				      "iitlb	%0"
491 				      : "=&a"(tmp0), "=&a"(tmp1), "=&a"(tmp2),
492 					"=&a"(tmp3)
493 				      : "a"(tmpaddr - vaddr),
494 					"a"(paddr - vaddr),
495 					"a"(SZ_128M), "a"(SZ_512M),
496 					"a"(PAGE_SIZE),
497 					"a"((tmpaddr + SZ_512M) & PAGE_MASK)
498 				      : "memory");
499 	}
500 #endif
501 #endif
502 	__asm__ __volatile__ ("movi	a2, 0\n\t"
503 			      "wsr	a2, icountlevel\n\t"
504 			      "movi	a2, 0\n\t"
505 			      "wsr	a2, icount\n\t"
506 #if XCHAL_NUM_IBREAK > 0
507 			      "wsr	a2, ibreakenable\n\t"
508 #endif
509 #if XCHAL_HAVE_LOOPS
510 			      "wsr	a2, lcount\n\t"
511 #endif
512 			      "movi	a2, 0x1f\n\t"
513 			      "wsr	a2, ps\n\t"
514 			      "isync\n\t"
515 			      "jx	%0\n\t"
516 			      :
517 			      : "a" (XCHAL_RESET_VECTOR_VADDR)
518 			      : "a2");
519 	for (;;)
520 		;
521 }
522 
523 void machine_restart(char * cmd)
524 {
525 	platform_restart();
526 }
527 
528 void machine_halt(void)
529 {
530 	platform_halt();
531 	while (1);
532 }
533 
534 void machine_power_off(void)
535 {
536 	platform_power_off();
537 	while (1);
538 }
539 #ifdef CONFIG_PROC_FS
540 
541 /*
542  * Display some core information through /proc/cpuinfo.
543  */
544 
545 static int
546 c_show(struct seq_file *f, void *slot)
547 {
548 	/* high-level stuff */
549 	seq_printf(f, "CPU count\t: %u\n"
550 		      "CPU list\t: %*pbl\n"
551 		      "vendor_id\t: Tensilica\n"
552 		      "model\t\t: Xtensa " XCHAL_HW_VERSION_NAME "\n"
553 		      "core ID\t\t: " XCHAL_CORE_ID "\n"
554 		      "build ID\t: 0x%x\n"
555 		      "config ID\t: %08x:%08x\n"
556 		      "byte order\t: %s\n"
557 		      "cpu MHz\t\t: %lu.%02lu\n"
558 		      "bogomips\t: %lu.%02lu\n",
559 		      num_online_cpus(),
560 		      cpumask_pr_args(cpu_online_mask),
561 		      XCHAL_BUILD_UNIQUE_ID,
562 		      xtensa_get_sr(SREG_EPC), xtensa_get_sr(SREG_EXCSAVE),
563 		      XCHAL_HAVE_BE ?  "big" : "little",
564 		      ccount_freq/1000000,
565 		      (ccount_freq/10000) % 100,
566 		      loops_per_jiffy/(500000/HZ),
567 		      (loops_per_jiffy/(5000/HZ)) % 100);
568 	seq_puts(f, "flags\t\t: "
569 #if XCHAL_HAVE_NMI
570 		     "nmi "
571 #endif
572 #if XCHAL_HAVE_DEBUG
573 		     "debug "
574 # if XCHAL_HAVE_OCD
575 		     "ocd "
576 # endif
577 #endif
578 #if XCHAL_HAVE_DENSITY
579 	    	     "density "
580 #endif
581 #if XCHAL_HAVE_BOOLEANS
582 		     "boolean "
583 #endif
584 #if XCHAL_HAVE_LOOPS
585 		     "loop "
586 #endif
587 #if XCHAL_HAVE_NSA
588 		     "nsa "
589 #endif
590 #if XCHAL_HAVE_MINMAX
591 		     "minmax "
592 #endif
593 #if XCHAL_HAVE_SEXT
594 		     "sext "
595 #endif
596 #if XCHAL_HAVE_CLAMPS
597 		     "clamps "
598 #endif
599 #if XCHAL_HAVE_MAC16
600 		     "mac16 "
601 #endif
602 #if XCHAL_HAVE_MUL16
603 		     "mul16 "
604 #endif
605 #if XCHAL_HAVE_MUL32
606 		     "mul32 "
607 #endif
608 #if XCHAL_HAVE_MUL32_HIGH
609 		     "mul32h "
610 #endif
611 #if XCHAL_HAVE_FP
612 		     "fpu "
613 #endif
614 #if XCHAL_HAVE_S32C1I
615 		     "s32c1i "
616 #endif
617 #if XCHAL_HAVE_EXCLUSIVE
618 		     "exclusive "
619 #endif
620 		     "\n");
621 
622 	/* Registers. */
623 	seq_printf(f,"physical aregs\t: %d\n"
624 		     "misc regs\t: %d\n"
625 		     "ibreak\t\t: %d\n"
626 		     "dbreak\t\t: %d\n",
627 		     XCHAL_NUM_AREGS,
628 		     XCHAL_NUM_MISC_REGS,
629 		     XCHAL_NUM_IBREAK,
630 		     XCHAL_NUM_DBREAK);
631 
632 
633 	/* Interrupt. */
634 	seq_printf(f,"num ints\t: %d\n"
635 		     "ext ints\t: %d\n"
636 		     "int levels\t: %d\n"
637 		     "timers\t\t: %d\n"
638 		     "debug level\t: %d\n",
639 		     XCHAL_NUM_INTERRUPTS,
640 		     XCHAL_NUM_EXTINTERRUPTS,
641 		     XCHAL_NUM_INTLEVELS,
642 		     XCHAL_NUM_TIMERS,
643 		     XCHAL_DEBUGLEVEL);
644 
645 	/* Cache */
646 	seq_printf(f,"icache line size: %d\n"
647 		     "icache ways\t: %d\n"
648 		     "icache size\t: %d\n"
649 		     "icache flags\t: "
650 #if XCHAL_ICACHE_LINE_LOCKABLE
651 		     "lock "
652 #endif
653 		     "\n"
654 		     "dcache line size: %d\n"
655 		     "dcache ways\t: %d\n"
656 		     "dcache size\t: %d\n"
657 		     "dcache flags\t: "
658 #if XCHAL_DCACHE_IS_WRITEBACK
659 		     "writeback "
660 #endif
661 #if XCHAL_DCACHE_LINE_LOCKABLE
662 		     "lock "
663 #endif
664 		     "\n",
665 		     XCHAL_ICACHE_LINESIZE,
666 		     XCHAL_ICACHE_WAYS,
667 		     XCHAL_ICACHE_SIZE,
668 		     XCHAL_DCACHE_LINESIZE,
669 		     XCHAL_DCACHE_WAYS,
670 		     XCHAL_DCACHE_SIZE);
671 
672 	return 0;
673 }
674 
675 /*
676  * We show only CPU #0 info.
677  */
678 static void *
679 c_start(struct seq_file *f, loff_t *pos)
680 {
681 	return (*pos == 0) ? (void *)1 : NULL;
682 }
683 
684 static void *
685 c_next(struct seq_file *f, void *v, loff_t *pos)
686 {
687 	++*pos;
688 	return c_start(f, pos);
689 }
690 
691 static void
692 c_stop(struct seq_file *f, void *v)
693 {
694 }
695 
696 const struct seq_operations cpuinfo_op =
697 {
698 	.start	= c_start,
699 	.next	= c_next,
700 	.stop	= c_stop,
701 	.show	= c_show,
702 };
703 
704 #endif /* CONFIG_PROC_FS */
705