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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 
 
 
 
  4 */
  5
  6#include <linux/seq_file.h>
  7#include <linux/fs.h>
  8#include <linux/delay.h>
  9#include <linux/root_dev.h>
 10#include <linux/clk.h>
 11#include <linux/clocksource.h>
 12#include <linux/console.h>
 13#include <linux/module.h>
 14#include <linux/sizes.h>
 15#include <linux/cpu.h>
 16#include <linux/of_clk.h>
 17#include <linux/of_fdt.h>
 18#include <linux/of.h>
 19#include <linux/cache.h>
 20#include <uapi/linux/mount.h>
 21#include <asm/sections.h>
 22#include <asm/arcregs.h>
 23#include <asm/asserts.h>
 24#include <asm/tlb.h>
 25#include <asm/setup.h>
 26#include <asm/page.h>
 27#include <asm/irq.h>
 28#include <asm/unwind.h>
 29#include <asm/mach_desc.h>
 30#include <asm/smp.h>
 31#include <asm/dsp-impl.h>
 32#include <soc/arc/mcip.h>
 33
 34#define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
 35
 36unsigned int intr_to_DE_cnt;
 37
 38/* Part of U-boot ABI: see head.S */
 39int __initdata uboot_tag;
 40int __initdata uboot_magic;
 41char __initdata *uboot_arg;
 42
 43const struct machine_desc *machine_desc;
 44
 45struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
 46
 47struct cpuinfo_arc {
 48	int arcver;
 49	unsigned int t0:1, t1:1;
 50	struct {
 51		unsigned long base;
 52		unsigned int sz;
 53	} iccm, dccm;
 54};
 55
 56#ifdef CONFIG_ISA_ARCV2
 57
 58static const struct id_to_str arc_hs_rel[] = {
 59	/* ID.ARCVER,	Release */
 60	{ 0x51, 	"R2.0" },
 61	{ 0x52, 	"R2.1" },
 62	{ 0x53,		"R3.0" },
 
 
 
 
 
 63};
 64
 65static const struct id_to_str arc_hs_ver54_rel[] = {
 66	/* UARCH.MAJOR,	Release */
 67	{  0,		"R3.10a"},
 68	{  1,		"R3.50a"},
 69	{  2,		"R3.60a"},
 70	{  3,		"R4.00a"},
 71	{  0xFF,	NULL   }
 72};
 73#endif
 
 
 74
 75static int
 76arcompact_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
 77{
 78	int n = 0;
 79#ifdef CONFIG_ISA_ARCOMPACT
 80	char *cpu_nm, *isa_nm = "ARCompact";
 81	struct bcr_fp_arcompact fpu_sp, fpu_dp;
 82	int atomic = 0, be, present;
 83	int bpu_full, bpu_cache, bpu_pred;
 84	struct bcr_bpu_arcompact bpu;
 85	struct bcr_iccm_arcompact iccm;
 86	struct bcr_dccm_arcompact dccm;
 87	struct bcr_generic isa;
 88
 89	READ_BCR(ARC_REG_ISA_CFG_BCR, isa);
 90
 91	if (!isa.ver)	/* ISA BCR absent, use Kconfig info */
 92		atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
 93	else {
 94		/* ARC700_BUILD only has 2 bits of isa info */
 95		atomic = isa.info & 1;
 96	}
 97
 98	be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
 99
100	if (info->arcver < 0x34)
101		cpu_nm = "ARC750";
102	else
103		cpu_nm = "ARC770";
104
105	n += scnprintf(buf + n, len - n, "processor [%d]\t: %s (%s ISA) %s%s%s\n",
106		       c, cpu_nm, isa_nm,
107		       IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
108		       IS_AVAIL1(be, "[Big-Endian]"));
109
110	READ_BCR(ARC_REG_FP_BCR, fpu_sp);
111	READ_BCR(ARC_REG_DPFP_BCR, fpu_dp);
 
 
 
112
113	if (fpu_sp.ver | fpu_dp.ver)
114		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
115			       IS_AVAIL1(fpu_sp.ver, "SP "),
116			       IS_AVAIL1(fpu_dp.ver, "DP "));
117
118	READ_BCR(ARC_REG_BPU_BCR, bpu);
119	bpu_full = bpu.fam ? 1 : 0;
120	bpu_cache = 256 << (bpu.ent - 1);
121	bpu_pred = 256 << (bpu.ent - 1);
 
 
 
 
 
 
 
 
 
122
123	n += scnprintf(buf + n, len - n,
124			"BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
125			IS_AVAIL1(bpu_full, "full"),
126			IS_AVAIL1(!bpu_full, "partial"),
127			bpu_cache, bpu_pred);
128
129	READ_BCR(ARC_REG_ICCM_BUILD, iccm);
130	if (iccm.ver) {
131		info->iccm.sz = 4096 << iccm.sz;	/* 8K to 512K */
132		info->iccm.base = iccm.base << 16;
133	}
134
135	READ_BCR(ARC_REG_DCCM_BUILD, dccm);
136	if (dccm.ver) {
137		unsigned long base;
138		info->dccm.sz = 2048 << dccm.sz;	/* 2K to 256K */
 
139
140		base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD);
141		info->dccm.base = base & ~0xF;
 
142	}
143
144	/* ARCompact ISA specific sanity checks */
145	present = fpu_dp.ver;	/* SP has no arch visible regs */
146	CHK_OPT_STRICT(CONFIG_ARC_FPU_SAVE_RESTORE, present);
147#endif
148	return n;
149
150}
151
152static int arcv2_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
153{
154	int n = 0;
155#ifdef CONFIG_ISA_ARCV2
156	const char *release = "", *cpu_nm = "HS38", *isa_nm = "ARCv2";
157	int dual_issue = 0, dual_enb = 0, mpy_opt, present;
158	int bpu_full, bpu_cache, bpu_pred, bpu_ret_stk;
159	char mpy_nm[16], lpb_nm[32];
160	struct bcr_isa_arcv2 isa;
161	struct bcr_mpy mpy;
162	struct bcr_fp_arcv2 fpu;
163	struct bcr_bpu_arcv2 bpu;
164	struct bcr_lpb lpb;
165	struct bcr_iccm_arcv2 iccm;
166	struct bcr_dccm_arcv2 dccm;
167	struct bcr_erp erp;
168
169	/*
170	 * Initial HS cores bumped AUX IDENTITY.ARCVER for each release until
171	 * ARCVER 0x54 which introduced AUX MICRO_ARCH_BUILD and subsequent
172	 * releases only update it.
173	 */
174
175	if (info->arcver > 0x50 && info->arcver <= 0x53) {
176		release = arc_hs_rel[info->arcver - 0x51].str;
177	} else {
178		const struct id_to_str *tbl;
179		struct bcr_uarch_build uarch;
180
181		READ_BCR(ARC_REG_MICRO_ARCH_BCR, uarch);
 
182
183		for (tbl = &arc_hs_ver54_rel[0]; tbl->id != 0xFF; tbl++) {
184			if (uarch.maj == tbl->id) {
185				release = tbl->str;
186				break;
187			}
188		}
189		if (uarch.prod == 4) {
190			unsigned int exec_ctrl;
191
192			cpu_nm = "HS48";
193			dual_issue = 1;
194			/* if dual issue hardware, is it enabled ? */
195			READ_BCR(AUX_EXEC_CTRL, exec_ctrl);
196			dual_enb = !(exec_ctrl & 1);
197		}
198	}
 
199
200	READ_BCR(ARC_REG_ISA_CFG_BCR, isa);
 
 
 
201
202	n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s%s%s\n",
203		       c, cpu_nm, release, isa_nm,
204		       IS_AVAIL1(isa.be, "[Big-Endian]"),
205		       IS_AVAIL3(dual_issue, dual_enb, " Dual-Issue "));
206
207	READ_BCR(ARC_REG_MPY_BCR, mpy);
208	mpy_opt = 2;	/* stock MPY/MPYH */
209	if (mpy.dsp)	/* OPT 7-9 */
210		mpy_opt = mpy.dsp + 6;
211
212	scnprintf(mpy_nm, 16, "mpy[opt %d] ", mpy_opt);
213
214	READ_BCR(ARC_REG_FP_V2_BCR, fpu);
215
216	n += scnprintf(buf + n, len - n, "ISA Extn\t: %s%s%s%s%s%s%s%s%s%s%s\n",
217		       IS_AVAIL2(isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
218		       IS_AVAIL2(isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
219		       IS_AVAIL2(isa.unalign, "unalign ", CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS),
220		       IS_AVAIL1(mpy.ver, mpy_nm),
221		       IS_AVAIL1(isa.div_rem, "div_rem "),
222		       IS_AVAIL1((fpu.sp | fpu.dp), "  FPU:"),
223		       IS_AVAIL1(fpu.sp, " sp"),
224		       IS_AVAIL1(fpu.dp, " dp"));
225
226	READ_BCR(ARC_REG_BPU_BCR, bpu);
227	bpu_full = bpu.ft;
228	bpu_cache = 256 << bpu.bce;
229	bpu_pred = 2048 << bpu.pte;
230	bpu_ret_stk = 4 << bpu.rse;
231
232	READ_BCR(ARC_REG_LPB_BUILD, lpb);
233	if (lpb.ver) {
234		unsigned int ctl;
235		ctl = read_aux_reg(ARC_REG_LPB_CTRL);
236
237		scnprintf(lpb_nm, sizeof(lpb_nm), " Loop Buffer:%d %s",
238			  lpb.entries, IS_DISABLED_RUN(!ctl));
239	}
240
241	n += scnprintf(buf + n, len - n,
242			"BPU\t\t: %s%s match, cache:%d, Predict Table:%d Return stk: %d%s\n",
243			IS_AVAIL1(bpu_full, "full"),
244			IS_AVAIL1(!bpu_full, "partial"),
245			bpu_cache, bpu_pred, bpu_ret_stk,
246			lpb_nm);
247
248	READ_BCR(ARC_REG_ICCM_BUILD, iccm);
249	if (iccm.ver) {
250		unsigned long base;
251		info->iccm.sz = 256 << iccm.sz00;	/* 512B to 16M */
252		if (iccm.sz00 == 0xF && iccm.sz01 > 0)
253			info->iccm.sz <<= iccm.sz01;
254		base = read_aux_reg(ARC_REG_AUX_ICCM);
255		info->iccm.base = base & 0xF0000000;
256	}
257
258	READ_BCR(ARC_REG_DCCM_BUILD, dccm);
259	if (dccm.ver) {
260		unsigned long base;
261		info->dccm.sz = 256 << dccm.sz0;
262		if (dccm.sz0 == 0xF && dccm.sz1 > 0)
263			info->dccm.sz <<= dccm.sz1;
264		base = read_aux_reg(ARC_REG_AUX_DCCM);
265		info->dccm.base = base & 0xF0000000;
266	}
267
268	/* Error Protection: ECC/Parity */
269	READ_BCR(ARC_REG_ERP_BUILD, erp);
270	if (erp.ver) {
271		struct ctl_erp ctl;
272		READ_BCR(ARC_REG_ERP_CTRL, ctl);
273		/* inverted bits: 0 means enabled */
274		n += scnprintf(buf + n, len - n, "Extn [ECC]\t: %s%s%s%s%s%s\n",
275				IS_AVAIL3(erp.ic,  !ctl.dpi, "IC "),
276				IS_AVAIL3(erp.dc,  !ctl.dpd, "DC "),
277				IS_AVAIL3(erp.mmu, !ctl.mpd, "MMU "));
278	}
279
280	/* ARCv2 ISA specific sanity checks */
281	present = fpu.sp | fpu.dp | mpy.dsp;	/* DSP and/or FPU */
282	CHK_OPT_STRICT(CONFIG_ARC_HAS_ACCL_REGS, present);
283
284	dsp_config_check();
285#endif
286	return n;
287}
288
289static char *arc_cpu_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
290{
291	struct bcr_identity ident;
292	struct bcr_timer timer;
293	struct bcr_generic bcr;
294	struct mcip_bcr mp;
295	struct bcr_actionpoint ap;
296	unsigned long vec_base;
297	int ap_num, ap_full, smart, rtt, n;
 
 
 
 
 
 
298
299	memset(info, 0, sizeof(struct cpuinfo_arc));
 
 
 
 
 
 
 
 
 
300
301	READ_BCR(AUX_IDENTITY, ident);
302	info->arcver = ident.family;
303
304	n = scnprintf(buf, len,
305		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
306		       ident.family, ident.cpu_id, ident.chip_id);
 
 
 
 
307
 
308	if (is_isa_arcompact()) {
309		n += arcompact_mumbojumbo(c, info, buf + n, len - n);
310	} else if (is_isa_arcv2()){
311		n += arcv2_mumbojumbo(c, info, buf + n, len - n);
312	}
313
314	n += arc_mmu_mumbojumbo(c, buf + n, len - n);
315	n += arc_cache_mumbojumbo(c, buf + n, len - n);
316
317	READ_BCR(ARC_REG_TIMERS_BCR, timer);
318	info->t0 = timer.t0;
319	info->t1 = timer.t1;
 
 
320
321	READ_BCR(ARC_REG_MCIP_BCR, mp);
322	vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
 
 
 
 
 
323
324	n += scnprintf(buf + n, len - n,
325		       "Timers\t\t: %s%s%s%s%s%s\nVector Table\t: %#lx\n",
326		       IS_AVAIL1(timer.t0, "Timer0 "),
327		       IS_AVAIL1(timer.t1, "Timer1 "),
328		       IS_AVAIL2(timer.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
329		       IS_AVAIL2(mp.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
330		       vec_base);
331
332	READ_BCR(ARC_REG_AP_BCR, ap);
333	if (ap.ver) {
334		ap_num = 2 << ap.num;
335		ap_full = !ap.min;
336	}
337
338	READ_BCR(ARC_REG_SMART_BCR, bcr);
339	smart = bcr.ver ? 1 : 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340
341	READ_BCR(ARC_REG_RTT_BCR, bcr);
342	rtt = bcr.ver ? 1 : 0;
343
344	if (ap.ver | smart | rtt) {
345		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s",
346			       IS_AVAIL1(smart, "smaRT "),
347			       IS_AVAIL1(rtt, "RTT "));
348		if (ap.ver) {
349			n += scnprintf(buf + n, len - n, "ActionPoint %d/%s",
350				       ap_num,
351				       ap_full ? "full":"min");
352		}
353		n += scnprintf(buf + n, len - n, "\n");
354	}
355
356	if (info->dccm.sz || info->iccm.sz)
 
 
 
 
 
 
 
 
 
357		n += scnprintf(buf + n, len - n,
358			       "Extn [CCM]\t: DCCM @ %lx, %d KB / ICCM: @ %lx, %d KB\n",
359			       info->dccm.base, TO_KB(info->dccm.sz),
360			       info->iccm.base, TO_KB(info->iccm.sz));
 
361
362	return buf;
363}
364
365void chk_opt_strict(char *opt_name, bool hw_exists, bool opt_ena)
366{
367	if (hw_exists && !opt_ena)
368		pr_warn(" ! Enable %s for working apps\n", opt_name);
369	else if (!hw_exists && opt_ena)
370		panic("Disable %s, hardware NOT present\n", opt_name);
371}
372
373void chk_opt_weak(char *opt_name, bool hw_exists, bool opt_ena)
374{
375	if (!hw_exists && opt_ena)
376		panic("Disable %s, hardware NOT present\n", opt_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
377}
378
379/*
380 * ISA agnostic sanity checks
381 */
382static void arc_chk_core_config(struct cpuinfo_arc *info)
383{
384	if (!info->t0)
 
 
 
385		panic("Timer0 is not present!\n");
386
387	if (!info->t1)
388		panic("Timer1 is not present!\n");
389
390#ifdef CONFIG_ARC_HAS_DCCM
391	/*
392	 * DCCM can be arbit placed in hardware.
393	 * Make sure its placement/sz matches what Linux is built with
394	 */
395	if ((unsigned int)__arc_dccm_base != info->dccm.base)
396		panic("Linux built with incorrect DCCM Base address\n");
397
398	if (CONFIG_ARC_DCCM_SZ * SZ_1K != info->dccm.sz)
399		panic("Linux built with incorrect DCCM Size\n");
400#endif
401
402#ifdef CONFIG_ARC_HAS_ICCM
403	if (CONFIG_ARC_ICCM_SZ * SZ_1K != info->iccm.sz)
404		panic("Linux built with incorrect ICCM Size\n");
405#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
406}
407
408/*
409 * Initialize and setup the processor core
410 * This is called by all the CPUs thus should not do special case stuff
411 *    such as only for boot CPU etc
412 */
413
414void setup_processor(void)
415{
416	struct cpuinfo_arc info;
417	int c = smp_processor_id();
418	char str[512];
 
419
420	pr_info("%s", arc_cpu_mumbojumbo(c, &info, str, sizeof(str)));
421	pr_info("%s", arc_platform_smp_cpuinfo());
422
423	arc_chk_core_config(&info);
424
425	arc_init_IRQ();
426	arc_mmu_init();
427	arc_cache_init();
428
 
 
 
 
429}
430
431static inline bool uboot_arg_invalid(unsigned long addr)
432{
433	/*
434	 * Check that it is a untranslated address (although MMU is not enabled
435	 * yet, it being a high address ensures this is not by fluke)
436	 */
437	if (addr < PAGE_OFFSET)
438		return true;
439
440	/* Check that address doesn't clobber resident kernel image */
441	return addr >= (unsigned long)_stext && addr <= (unsigned long)_end;
442}
443
444#define IGNORE_ARGS		"Ignore U-boot args: "
445
446/* uboot_tag values for U-boot - kernel ABI revision 0; see head.S */
447#define UBOOT_TAG_NONE		0
448#define UBOOT_TAG_CMDLINE	1
449#define UBOOT_TAG_DTB		2
450/* We always pass 0 as magic from U-boot */
451#define UBOOT_MAGIC_VALUE	0
452
453void __init handle_uboot_args(void)
454{
455	bool use_embedded_dtb = true;
456	bool append_cmdline = false;
457
458	/* check that we know this tag */
459	if (uboot_tag != UBOOT_TAG_NONE &&
460	    uboot_tag != UBOOT_TAG_CMDLINE &&
461	    uboot_tag != UBOOT_TAG_DTB) {
462		pr_warn(IGNORE_ARGS "invalid uboot tag: '%08x'\n", uboot_tag);
463		goto ignore_uboot_args;
464	}
465
466	if (uboot_magic != UBOOT_MAGIC_VALUE) {
467		pr_warn(IGNORE_ARGS "non zero uboot magic\n");
468		goto ignore_uboot_args;
469	}
470
471	if (uboot_tag != UBOOT_TAG_NONE &&
472            uboot_arg_invalid((unsigned long)uboot_arg)) {
473		pr_warn(IGNORE_ARGS "invalid uboot arg: '%px'\n", uboot_arg);
474		goto ignore_uboot_args;
475	}
476
477	/* see if U-boot passed an external Device Tree blob */
478	if (uboot_tag == UBOOT_TAG_DTB) {
479		machine_desc = setup_machine_fdt((void *)uboot_arg);
480
481		/* external Device Tree blob is invalid - use embedded one */
482		use_embedded_dtb = !machine_desc;
483	}
484
485	if (uboot_tag == UBOOT_TAG_CMDLINE)
486		append_cmdline = true;
487
488ignore_uboot_args:
489
490	if (use_embedded_dtb) {
491		machine_desc = setup_machine_fdt(__dtb_start);
492		if (!machine_desc)
493			panic("Embedded DT invalid\n");
494	}
495
496	/*
497	 * NOTE: @boot_command_line is populated by setup_machine_fdt() so this
498	 * append processing can only happen after.
499	 */
500	if (append_cmdline) {
501		/* Ensure a whitespace between the 2 cmdlines */
502		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
503		strlcat(boot_command_line, uboot_arg, COMMAND_LINE_SIZE);
 
 
 
 
504	}
505}
506
507void __init setup_arch(char **cmdline_p)
508{
509	handle_uboot_args();
510
511	/* Save unparsed command line copy for /proc/cmdline */
512	*cmdline_p = boot_command_line;
513
514	/* To force early parsing of things like mem=xxx */
515	parse_early_param();
516
517	/* Platform/board specific: e.g. early console registration */
518	if (machine_desc->init_early)
519		machine_desc->init_early();
520
521	smp_init_cpus();
522
523	setup_processor();
524	setup_arch_memory();
525
526	/* copy flat DT out of .init and then unflatten it */
527	unflatten_and_copy_device_tree();
528
529	/* Can be issue if someone passes cmd line arg "ro"
530	 * But that is unlikely so keeping it as it is
531	 */
532	root_mountflags &= ~MS_RDONLY;
533
 
 
 
 
534	arc_unwind_init();
535}
536
537/*
538 * Called from start_kernel() - boot CPU only
539 */
540void __init time_init(void)
541{
542	of_clk_init(NULL);
543	timer_probe();
544}
545
546static int __init customize_machine(void)
547{
548	if (machine_desc->init_machine)
549		machine_desc->init_machine();
550
551	return 0;
552}
553arch_initcall(customize_machine);
554
555static int __init init_late_machine(void)
556{
557	if (machine_desc->init_late)
558		machine_desc->init_late();
559
560	return 0;
561}
562late_initcall(init_late_machine);
563/*
564 *  Get CPU information for use by the procfs.
565 */
566
567#define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
568#define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
569
570static int show_cpuinfo(struct seq_file *m, void *v)
571{
572	char *str;
573	int cpu_id = ptr_to_cpu(v);
574	struct device *cpu_dev = get_cpu_device(cpu_id);
575	struct cpuinfo_arc info;
576	struct clk *cpu_clk;
577	unsigned long freq = 0;
578
579	if (!cpu_online(cpu_id)) {
580		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
581		goto done;
582	}
583
584	str = (char *)__get_free_page(GFP_KERNEL);
585	if (!str)
586		goto done;
587
588	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, &info, str, PAGE_SIZE));
589
590	cpu_clk = clk_get(cpu_dev, NULL);
591	if (IS_ERR(cpu_clk)) {
592		seq_printf(m, "CPU speed \t: Cannot get clock for processor [%d]\n",
593			   cpu_id);
594	} else {
595		freq = clk_get_rate(cpu_clk);
596	}
597	if (freq)
598		seq_printf(m, "CPU speed\t: %lu.%02lu Mhz\n",
599			   freq / 1000000, (freq / 10000) % 100);
600
601	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
602		   loops_per_jiffy / (500000 / HZ),
603		   (loops_per_jiffy / (5000 / HZ)) % 100);
604
 
 
 
605	seq_printf(m, arc_platform_smp_cpuinfo());
606
607	free_page((unsigned long)str);
608done:
609	seq_printf(m, "\n");
610
611	return 0;
612}
613
614static void *c_start(struct seq_file *m, loff_t *pos)
615{
616	/*
617	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
618	 * However since NULL is also a valid cpu-id (0), we use a round-about
619	 * way to pass it w/o having to kmalloc/free a 2 byte string.
620	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
621	 */
622	return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
623}
624
625static void *c_next(struct seq_file *m, void *v, loff_t *pos)
626{
627	++*pos;
628	return c_start(m, pos);
629}
630
631static void c_stop(struct seq_file *m, void *v)
632{
633}
634
635const struct seq_operations cpuinfo_op = {
636	.start	= c_start,
637	.next	= c_next,
638	.stop	= c_stop,
639	.show	= show_cpuinfo
640};
641
642static DEFINE_PER_CPU(struct cpu, cpu_topology);
643
644static int __init topology_init(void)
645{
646	int cpu;
647
648	for_each_present_cpu(cpu)
649	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
650
651	return 0;
652}
653
654subsys_initcall(topology_init);
v4.10.11
 
  1/*
  2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 */
  8
  9#include <linux/seq_file.h>
 10#include <linux/fs.h>
 11#include <linux/delay.h>
 12#include <linux/root_dev.h>
 13#include <linux/clk-provider.h>
 14#include <linux/clocksource.h>
 15#include <linux/console.h>
 16#include <linux/module.h>
 
 17#include <linux/cpu.h>
 
 18#include <linux/of_fdt.h>
 19#include <linux/of.h>
 20#include <linux/cache.h>
 
 21#include <asm/sections.h>
 22#include <asm/arcregs.h>
 
 23#include <asm/tlb.h>
 24#include <asm/setup.h>
 25#include <asm/page.h>
 26#include <asm/irq.h>
 27#include <asm/unwind.h>
 28#include <asm/mach_desc.h>
 29#include <asm/smp.h>
 
 
 30
 31#define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
 32
 33unsigned int intr_to_DE_cnt;
 34
 35/* Part of U-boot ABI: see head.S */
 36int __initdata uboot_tag;
 
 37char __initdata *uboot_arg;
 38
 39const struct machine_desc *machine_desc;
 40
 41struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
 42
 43struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
 
 
 
 
 
 
 
 
 
 44
 45static const struct id_to_str arc_cpu_rel[] = {
 46#ifdef CONFIG_ISA_ARCOMPACT
 47	{ 0x34, "R4.10"},
 48	{ 0x35, "R4.11"},
 49#else
 50	{ 0x51, "R2.0" },
 51	{ 0x52, "R2.1" },
 52	{ 0x53, "R3.0" },
 53#endif
 54	{ 0x00, NULL   }
 55};
 56
 57static const struct id_to_str arc_cpu_nm[] = {
 58#ifdef CONFIG_ISA_ARCOMPACT
 59	{ 0x20, "ARC 600"   },
 60	{ 0x30, "ARC 770"   },  /* 750 identified seperately */
 61#else
 62	{ 0x40, "ARC EM"  },
 63	{ 0x50, "ARC HS38"  },
 
 64#endif
 65	{ 0x00, "Unknown"   }
 66};
 67
 68static void read_decode_ccm_bcr(struct cpuinfo_arc *cpu)
 
 69{
 70	if (is_isa_arcompact()) {
 71		struct bcr_iccm_arcompact iccm;
 72		struct bcr_dccm_arcompact dccm;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 73
 74		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
 75		if (iccm.ver) {
 76			cpu->iccm.sz = 4096 << iccm.sz;	/* 8K to 512K */
 77			cpu->iccm.base_addr = iccm.base << 16;
 78		}
 79
 80		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
 81		if (dccm.ver) {
 82			unsigned long base;
 83			cpu->dccm.sz = 2048 << dccm.sz;	/* 2K to 256K */
 84
 85			base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD);
 86			cpu->dccm.base_addr = base & ~0xF;
 87		}
 88	} else {
 89		struct bcr_iccm_arcv2 iccm;
 90		struct bcr_dccm_arcv2 dccm;
 91		unsigned long region;
 92
 93		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
 94		if (iccm.ver) {
 95			cpu->iccm.sz = 256 << iccm.sz00;	/* 512B to 16M */
 96			if (iccm.sz00 == 0xF && iccm.sz01 > 0)
 97				cpu->iccm.sz <<= iccm.sz01;
 98
 99			region = read_aux_reg(ARC_REG_AUX_ICCM);
100			cpu->iccm.base_addr = region & 0xF0000000;
101		}
 
 
 
 
 
 
 
 
102
103		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
104		if (dccm.ver) {
105			cpu->dccm.sz = 256 << dccm.sz0;
106			if (dccm.sz0 == 0xF && dccm.sz1 > 0)
107				cpu->dccm.sz <<= dccm.sz1;
108
109			region = read_aux_reg(ARC_REG_AUX_DCCM);
110			cpu->dccm.base_addr = region & 0xF0000000;
111		}
112	}
 
 
 
 
 
 
 
113}
114
115static void read_arc_build_cfg_regs(void)
116{
117	struct bcr_timer timer;
118	struct bcr_generic bcr;
119	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
120	const struct id_to_str *tbl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
121
122	FIX_PTR(cpu);
 
 
 
 
123
124	READ_BCR(AUX_IDENTITY, cpu->core);
125	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
126
127	for (tbl = &arc_cpu_rel[0]; tbl->id != 0; tbl++) {
128		if (cpu->core.family == tbl->id) {
129			cpu->details = tbl->str;
130			break;
 
131		}
132	}
 
133
134	for (tbl = &arc_cpu_nm[0]; tbl->id != 0; tbl++) {
135		if ((cpu->core.family & 0xF0) == tbl->id)
136			break;
 
 
 
137	}
138	cpu->name = tbl->str;
139
140	READ_BCR(ARC_REG_TIMERS_BCR, timer);
141	cpu->extn.timer0 = timer.t0;
142	cpu->extn.timer1 = timer.t1;
143	cpu->extn.rtc = timer.rtc;
144
145	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
146
147	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
 
 
148
149	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
150	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
151	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
152	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
153	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
154	cpu->extn.swape = (cpu->core.family >= 0x34) ? 1 :
155				IS_ENABLED(CONFIG_ARC_HAS_SWAPE);
 
 
 
 
 
 
 
 
 
156
157	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
 
 
 
 
 
 
 
 
158
159	/* Read CCM BCRs for boot reporting even if not enabled in Kconfig */
160	read_decode_ccm_bcr(cpu);
 
 
 
 
 
 
 
 
 
161
162	read_decode_mmu_bcr();
163	read_decode_cache_bcr();
 
164
165	if (is_isa_arcompact()) {
166		struct bcr_fp_arcompact sp, dp;
167		struct bcr_bpu_arcompact bpu;
 
168
169		READ_BCR(ARC_REG_FP_BCR, sp);
170		READ_BCR(ARC_REG_DPFP_BCR, dp);
171		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
172		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
173
174		READ_BCR(ARC_REG_BPU_BCR, bpu);
175		cpu->bpu.ver = bpu.ver;
176		cpu->bpu.full = bpu.fam ? 1 : 0;
177		if (bpu.ent) {
178			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
179			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
180		}
181	} else {
182		struct bcr_fp_arcv2 spdp;
183		struct bcr_bpu_arcv2 bpu;
184
185		READ_BCR(ARC_REG_FP_V2_BCR, spdp);
186		cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
187		cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
188
189		READ_BCR(ARC_REG_BPU_BCR, bpu);
190		cpu->bpu.ver = bpu.ver;
191		cpu->bpu.full = bpu.ft;
192		cpu->bpu.num_cache = 256 << bpu.bce;
193		cpu->bpu.num_pred = 2048 << bpu.pte;
194	}
195
196	READ_BCR(ARC_REG_AP_BCR, bcr);
197	cpu->extn.ap = bcr.ver ? 1 : 0;
198
199	READ_BCR(ARC_REG_SMART_BCR, bcr);
200	cpu->extn.smart = bcr.ver ? 1 : 0;
201
202	READ_BCR(ARC_REG_RTT_BCR, bcr);
203	cpu->extn.rtt = bcr.ver ? 1 : 0;
204
205	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
206
207	/* some hacks for lack of feature BCR info in old ARC700 cores */
208	if (is_isa_arcompact()) {
209		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
210			cpu->isa.atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
211		else
212			cpu->isa.atomic = cpu->isa.atomic1;
213
214		cpu->isa.be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
 
215
216		 /* there's no direct way to distinguish 750 vs. 770 */
217		if (unlikely(cpu->core.family < 0x34 || cpu->mmu.ver < 3))
218			cpu->name = "ARC750";
219	}
220}
221
222static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
223{
224	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
225	struct bcr_identity *core = &cpu->core;
226	int i, n = 0;
227
228	FIX_PTR(cpu);
229
230	n += scnprintf(buf + n, len - n,
231		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
232		       core->family, core->cpu_id, core->chip_id);
 
 
 
 
 
 
 
 
 
 
233
234	n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s\n",
235		       cpu_id, cpu->name, cpu->details,
236		       is_isa_arcompact() ? "ARCompact" : "ARCv2",
237		       IS_AVAIL1(cpu->isa.be, "[Big-Endian]"));
238
239	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s%s%s\nISA Extn\t: ",
240		       IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
241		       IS_AVAIL1(cpu->extn.timer1, "Timer1 "),
242		       IS_AVAIL2(cpu->extn.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
243		       IS_AVAIL2(cpu->extn.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT));
244
245	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
246			   IS_AVAIL2(cpu->isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
247			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
248			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
249
250	if (i)
251		n += scnprintf(buf + n, len - n, "\n\t\t: ");
252
253	if (cpu->extn_mpy.ver) {
254		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
255			n += scnprintf(buf + n, len - n, "mpy ");
256		} else {
257			int opt = 2;	/* stock MPY/MPYH */
258
259			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
260				opt = cpu->extn_mpy.dsp + 6;
261
262			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
 
 
 
 
 
 
 
263		}
 
264	}
265
266	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
267		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
268		       IS_AVAIL1(cpu->extn.norm, "norm "),
269		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
270		       IS_AVAIL1(cpu->extn.swap, "swap "),
271		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
272		       IS_AVAIL1(cpu->extn.crc, "crc "),
273		       IS_AVAIL2(cpu->extn.swape, "swape", CONFIG_ARC_HAS_SWAPE));
274
275	if (cpu->bpu.ver)
276		n += scnprintf(buf + n, len - n,
277			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
278			      IS_AVAIL1(cpu->bpu.full, "full"),
279			      IS_AVAIL1(!cpu->bpu.full, "partial"),
280			      cpu->bpu.num_cache, cpu->bpu.num_pred);
281
282	return buf;
283}
284
285static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
286{
287	int n = 0;
288	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 
 
 
289
290	FIX_PTR(cpu);
291
292	n += scnprintf(buf + n, len - n, "Vector Table\t: %#x\n", cpu->vec_base);
293
294	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
295		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
296			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
297			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
298
299	if (cpu->extn.debug)
300		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
301			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
302			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
303			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
304
305	if (cpu->dccm.sz || cpu->iccm.sz)
306		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
307			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
308			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
309
310	n += scnprintf(buf + n, len - n, "OS ABI [v%d]\t: %s\n",
311			EF_ARC_OSABI_CURRENT >> 8,
312			EF_ARC_OSABI_CURRENT == EF_ARC_OSABI_V3 ?
313			"no-legacy-syscalls" : "64-bit data any register aligned");
314
315	return buf;
316}
317
318static void arc_chk_core_config(void)
 
 
 
319{
320	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
321	int fpu_enabled;
322
323	if (!cpu->extn.timer0)
324		panic("Timer0 is not present!\n");
325
326	if (!cpu->extn.timer1)
327		panic("Timer1 is not present!\n");
328
329#ifdef CONFIG_ARC_HAS_DCCM
330	/*
331	 * DCCM can be arbit placed in hardware.
332	 * Make sure it's placement/sz matches what Linux is built with
333	 */
334	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
335		panic("Linux built with incorrect DCCM Base address\n");
336
337	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
338		panic("Linux built with incorrect DCCM Size\n");
339#endif
340
341#ifdef CONFIG_ARC_HAS_ICCM
342	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
343		panic("Linux built with incorrect ICCM Size\n");
344#endif
345
346	/*
347	 * FP hardware/software config sanity
348	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
349	 * -If not, it will crash trying to save/restore the non-existant regs
350	 *
351	 * (only DPDP checked since SP has no arch visible regs)
352	 */
353	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
354
355	if (cpu->extn.fpu_dp && !fpu_enabled)
356		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
357	else if (!cpu->extn.fpu_dp && fpu_enabled)
358		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
359}
360
361/*
362 * Initialize and setup the processor core
363 * This is called by all the CPUs thus should not do special case stuff
364 *    such as only for boot CPU etc
365 */
366
367void setup_processor(void)
368{
 
 
369	char str[512];
370	int cpu_id = smp_processor_id();
371
372	read_arc_build_cfg_regs();
373	arc_init_IRQ();
374
375	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
376
 
377	arc_mmu_init();
378	arc_cache_init();
379
380	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
381	printk(arc_platform_smp_cpuinfo());
382
383	arc_chk_core_config();
384}
385
386static inline int is_kernel(unsigned long addr)
387{
388	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
389		return 1;
390	return 0;
 
 
 
 
 
 
391}
392
393void __init setup_arch(char **cmdline_p)
 
 
 
 
 
 
 
 
 
394{
395#ifdef CONFIG_ARC_UBOOT_SUPPORT
396	/* make sure that uboot passed pointer to cmdline/dtb is valid */
397	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
398		panic("Invalid uboot arg\n");
399
400	/* See if u-boot passed an external Device Tree blob */
401	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
402	if (!machine_desc)
403#endif
404	{
405		/* No, so try the embedded one */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
406		machine_desc = setup_machine_fdt(__dtb_start);
407		if (!machine_desc)
408			panic("Embedded DT invalid\n");
 
409
410		/*
411		 * If we are here, it is established that @uboot_arg didn't
412		 * point to DT blob. Instead if u-boot says it is cmdline,
413		 * append to embedded DT cmdline.
414		 * setup_machine_fdt() would have populated @boot_command_line
415		 */
416		if (uboot_tag == 1) {
417			/* Ensure a whitespace between the 2 cmdlines */
418			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
419			strlcat(boot_command_line, uboot_arg,
420				COMMAND_LINE_SIZE);
421		}
422	}
 
 
 
 
 
423
424	/* Save unparsed command line copy for /proc/cmdline */
425	*cmdline_p = boot_command_line;
426
427	/* To force early parsing of things like mem=xxx */
428	parse_early_param();
429
430	/* Platform/board specific: e.g. early console registration */
431	if (machine_desc->init_early)
432		machine_desc->init_early();
433
434	smp_init_cpus();
435
436	setup_processor();
437	setup_arch_memory();
438
439	/* copy flat DT out of .init and then unflatten it */
440	unflatten_and_copy_device_tree();
441
442	/* Can be issue if someone passes cmd line arg "ro"
443	 * But that is unlikely so keeping it as it is
444	 */
445	root_mountflags &= ~MS_RDONLY;
446
447#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
448	conswitchp = &dummy_con;
449#endif
450
451	arc_unwind_init();
452}
453
454/*
455 * Called from start_kernel() - boot CPU only
456 */
457void __init time_init(void)
458{
459	of_clk_init(NULL);
460	clocksource_probe();
461}
462
463static int __init customize_machine(void)
464{
465	if (machine_desc->init_machine)
466		machine_desc->init_machine();
467
468	return 0;
469}
470arch_initcall(customize_machine);
471
472static int __init init_late_machine(void)
473{
474	if (machine_desc->init_late)
475		machine_desc->init_late();
476
477	return 0;
478}
479late_initcall(init_late_machine);
480/*
481 *  Get CPU information for use by the procfs.
482 */
483
484#define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
485#define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
486
487static int show_cpuinfo(struct seq_file *m, void *v)
488{
489	char *str;
490	int cpu_id = ptr_to_cpu(v);
491	struct device_node *core_clk = of_find_node_by_name(NULL, "core_clk");
492	u32 freq = 0;
 
 
493
494	if (!cpu_online(cpu_id)) {
495		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
496		goto done;
497	}
498
499	str = (char *)__get_free_page(GFP_TEMPORARY);
500	if (!str)
501		goto done;
502
503	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
504
505	of_property_read_u32(core_clk, "clock-frequency", &freq);
 
 
 
 
 
 
506	if (freq)
507		seq_printf(m, "CPU speed\t: %u.%02u Mhz\n",
508			   freq / 1000000, (freq / 10000) % 100);
509
510	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
511		   loops_per_jiffy / (500000 / HZ),
512		   (loops_per_jiffy / (5000 / HZ)) % 100);
513
514	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
515	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
516	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
517	seq_printf(m, arc_platform_smp_cpuinfo());
518
519	free_page((unsigned long)str);
520done:
521	seq_printf(m, "\n");
522
523	return 0;
524}
525
526static void *c_start(struct seq_file *m, loff_t *pos)
527{
528	/*
529	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
530	 * However since NULL is also a valid cpu-id (0), we use a round-about
531	 * way to pass it w/o having to kmalloc/free a 2 byte string.
532	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
533	 */
534	return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
535}
536
537static void *c_next(struct seq_file *m, void *v, loff_t *pos)
538{
539	++*pos;
540	return c_start(m, pos);
541}
542
543static void c_stop(struct seq_file *m, void *v)
544{
545}
546
547const struct seq_operations cpuinfo_op = {
548	.start	= c_start,
549	.next	= c_next,
550	.stop	= c_stop,
551	.show	= show_cpuinfo
552};
553
554static DEFINE_PER_CPU(struct cpu, cpu_topology);
555
556static int __init topology_init(void)
557{
558	int cpu;
559
560	for_each_present_cpu(cpu)
561	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
562
563	return 0;
564}
565
566subsys_initcall(topology_init);