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setup.c

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linux-6.19.14/arch/arm/kernel/setup.c C
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/arch/arm/kernel/setup.c
   4 *
   5 *  Copyright (C) 1995-2001 Russell King
   6 */
   7#include <linux/efi.h>
   8#include <linux/export.h>
   9#include <linux/kernel.h>
  10#include <linux/stddef.h>
  11#include <linux/ioport.h>
  12#include <linux/delay.h>
  13#include <linux/utsname.h>
  14#include <linux/initrd.h>
  15#include <linux/console.h>
  16#include <linux/seq_file.h>
  17#include <linux/screen_info.h>
  18#include <linux/init.h>
  19#include <linux/kexec.h>
  20#include <linux/libfdt.h>
  21#include <linux/of.h>
  22#include <linux/of_fdt.h>
  23#include <linux/cpu.h>
  24#include <linux/interrupt.h>
  25#include <linux/smp.h>
  26#include <linux/proc_fs.h>
  27#include <linux/memblock.h>
  28#include <linux/bug.h>
  29#include <linux/compiler.h>
  30#include <linux/sort.h>
  31#include <linux/psci.h>
  32
  33#include <asm/unified.h>
  34#include <asm/cp15.h>
  35#include <asm/cpu.h>
  36#include <asm/cputype.h>
  37#include <asm/efi.h>
  38#include <asm/elf.h>
  39#include <asm/early_ioremap.h>
  40#include <asm/fixmap.h>
  41#include <asm/procinfo.h>
  42#include <asm/psci.h>
  43#include <asm/sections.h>
  44#include <asm/setup.h>
  45#include <asm/smp_plat.h>
  46#include <asm/mach-types.h>
  47#include <asm/cacheflush.h>
  48#include <asm/cachetype.h>
  49#include <asm/tlbflush.h>
  50#include <asm/xen/hypervisor.h>
  51
  52#include <asm/prom.h>
  53#include <asm/mach/arch.h>
  54#include <asm/mach/irq.h>
  55#include <asm/mach/time.h>
  56#include <asm/system_info.h>
  57#include <asm/system_misc.h>
  58#include <asm/traps.h>
  59#include <asm/unwind.h>
  60#include <asm/memblock.h>
  61#include <asm/virt.h>
  62#include <asm/kasan.h>
  63
  64#include "atags.h"
  65
  66
  67#if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
  68char fpe_type[8];
  69
  70static int __init fpe_setup(char *line)
  71{
  72	memcpy(fpe_type, line, 8);
  73	return 1;
  74}
  75
  76__setup("fpe=", fpe_setup);
  77#endif
  78
  79unsigned int processor_id;
  80EXPORT_SYMBOL(processor_id);
  81unsigned int __machine_arch_type __read_mostly;
  82EXPORT_SYMBOL(__machine_arch_type);
  83unsigned int cacheid __read_mostly;
  84EXPORT_SYMBOL(cacheid);
  85
  86unsigned int __atags_pointer __initdata;
  87
  88unsigned int system_rev;
  89EXPORT_SYMBOL(system_rev);
  90
  91const char *system_serial;
  92EXPORT_SYMBOL(system_serial);
  93
  94unsigned int system_serial_low;
  95EXPORT_SYMBOL(system_serial_low);
  96
  97unsigned int system_serial_high;
  98EXPORT_SYMBOL(system_serial_high);
  99
 100unsigned int elf_hwcap __read_mostly;
 101EXPORT_SYMBOL(elf_hwcap);
 102
 103unsigned int elf_hwcap2 __read_mostly;
 104EXPORT_SYMBOL(elf_hwcap2);
 105
 106
 107#ifdef MULTI_CPU
 108struct processor processor __ro_after_init;
 109#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
 110struct processor *cpu_vtable[NR_CPUS] = {
 111	[0] = &processor,
 112};
 113#endif
 114#endif
 115#ifdef MULTI_TLB
 116struct cpu_tlb_fns cpu_tlb __ro_after_init;
 117#endif
 118#ifdef MULTI_USER
 119struct cpu_user_fns cpu_user __ro_after_init;
 120#endif
 121#ifdef MULTI_CACHE
 122struct cpu_cache_fns cpu_cache __ro_after_init;
 123#endif
 124#ifdef CONFIG_OUTER_CACHE
 125struct outer_cache_fns outer_cache __ro_after_init;
 126EXPORT_SYMBOL(outer_cache);
 127#endif
 128
 129/*
 130 * Cached cpu_architecture() result for use by assembler code.
 131 * C code should use the cpu_architecture() function instead of accessing this
 132 * variable directly.
 133 */
 134int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
 135
 136struct stack {
 137	u32 irq[4];
 138	u32 abt[4];
 139	u32 und[4];
 140	u32 fiq[4];
 141} ____cacheline_aligned;
 142
 143#ifndef CONFIG_CPU_V7M
 144static struct stack stacks[NR_CPUS];
 145#endif
 146
 147char elf_platform[ELF_PLATFORM_SIZE];
 148EXPORT_SYMBOL(elf_platform);
 149
 150static const char *cpu_name;
 151static const char *machine_name;
 152static char __initdata cmd_line[COMMAND_LINE_SIZE];
 153const struct machine_desc *machine_desc __initdata;
 154
 155static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
 156#define ENDIANNESS ((char)endian_test.l)
 157
 158DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
 159
 160/*
 161 * Standard memory resources
 162 */
 163static struct resource mem_res[] = {
 164	{
 165		.name = "Video RAM",
 166		.start = 0,
 167		.end = 0,
 168		.flags = IORESOURCE_MEM
 169	},
 170	{
 171		.name = "Kernel code",
 172		.start = 0,
 173		.end = 0,
 174		.flags = IORESOURCE_SYSTEM_RAM
 175	},
 176	{
 177		.name = "Kernel data",
 178		.start = 0,
 179		.end = 0,
 180		.flags = IORESOURCE_SYSTEM_RAM
 181	}
 182};
 183
 184#define video_ram   mem_res[0]
 185#define kernel_code mem_res[1]
 186#define kernel_data mem_res[2]
 187
 188static struct resource io_res[] = {
 189	{
 190		.name = "reserved",
 191		.start = 0x3bc,
 192		.end = 0x3be,
 193		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 194	},
 195	{
 196		.name = "reserved",
 197		.start = 0x378,
 198		.end = 0x37f,
 199		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 200	},
 201	{
 202		.name = "reserved",
 203		.start = 0x278,
 204		.end = 0x27f,
 205		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 206	}
 207};
 208
 209#define lp0 io_res[0]
 210#define lp1 io_res[1]
 211#define lp2 io_res[2]
 212
 213static const char *proc_arch[] = {
 214	"undefined/unknown",
 215	"3",
 216	"4",
 217	"4T",
 218	"5",
 219	"5T",
 220	"5TE",
 221	"5TEJ",
 222	"6TEJ",
 223	"7",
 224	"7M",
 225	"?(12)",
 226	"?(13)",
 227	"?(14)",
 228	"?(15)",
 229	"?(16)",
 230	"?(17)",
 231};
 232
 233#ifdef CONFIG_CPU_V7M
 234static int __get_cpu_architecture(void)
 235{
 236	return CPU_ARCH_ARMv7M;
 237}
 238#else
 239static int __get_cpu_architecture(void)
 240{
 241	int cpu_arch;
 242
 243	if ((read_cpuid_id() & 0x0008f000) == 0) {
 244		cpu_arch = CPU_ARCH_UNKNOWN;
 245	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
 246		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
 247	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
 248		cpu_arch = (read_cpuid_id() >> 16) & 7;
 249		if (cpu_arch)
 250			cpu_arch += CPU_ARCH_ARMv3;
 251	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
 252		/* Revised CPUID format. Read the Memory Model Feature
 253		 * Register 0 and check for VMSAv7 or PMSAv7 */
 254		unsigned int mmfr0 = read_cpuid_ext(CPUID_EXT_MMFR0);
 255		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
 256		    (mmfr0 & 0x000000f0) >= 0x00000030)
 257			cpu_arch = CPU_ARCH_ARMv7;
 258		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
 259			 (mmfr0 & 0x000000f0) == 0x00000020)
 260			cpu_arch = CPU_ARCH_ARMv6;
 261		else
 262			cpu_arch = CPU_ARCH_UNKNOWN;
 263	} else
 264		cpu_arch = CPU_ARCH_UNKNOWN;
 265
 266	return cpu_arch;
 267}
 268#endif
 269
 270int __pure cpu_architecture(void)
 271{
 272	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
 273
 274	return __cpu_architecture;
 275}
 276
 277static int cpu_has_aliasing_icache(unsigned int arch)
 278{
 279	int aliasing_icache;
 280	unsigned int id_reg, num_sets, line_size;
 281
 282	/* PIPT caches never alias. */
 283	if (icache_is_pipt())
 284		return 0;
 285
 286	/* arch specifies the register format */
 287	switch (arch) {
 288	case CPU_ARCH_ARMv7:
 289		set_csselr(CSSELR_ICACHE | CSSELR_L1);
 290		isb();
 291		id_reg = read_ccsidr();
 292		line_size = 4 << ((id_reg & 0x7) + 2);
 293		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
 294		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
 295		break;
 296	case CPU_ARCH_ARMv6:
 297		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
 298		break;
 299	default:
 300		/* I-cache aliases will be handled by D-cache aliasing code */
 301		aliasing_icache = 0;
 302	}
 303
 304	return aliasing_icache;
 305}
 306
 307static void __init cacheid_init(void)
 308{
 309	unsigned int arch = cpu_architecture();
 310
 311	if (arch >= CPU_ARCH_ARMv6) {
 312		unsigned int cachetype = read_cpuid_cachetype();
 313
 314		if ((arch == CPU_ARCH_ARMv7M) && !(cachetype & 0xf000f)) {
 315			cacheid = 0;
 316		} else if ((cachetype & (7 << 29)) == 4 << 29) {
 317			/* ARMv7 register format */
 318			arch = CPU_ARCH_ARMv7;
 319			cacheid = CACHEID_VIPT_NONALIASING;
 320			switch (cachetype & (3 << 14)) {
 321			case (1 << 14):
 322				cacheid |= CACHEID_ASID_TAGGED;
 323				break;
 324			case (3 << 14):
 325				cacheid |= CACHEID_PIPT;
 326				break;
 327			}
 328		} else {
 329			arch = CPU_ARCH_ARMv6;
 330			if (cachetype & (1 << 23))
 331				cacheid = CACHEID_VIPT_ALIASING;
 332			else
 333				cacheid = CACHEID_VIPT_NONALIASING;
 334		}
 335		if (cpu_has_aliasing_icache(arch))
 336			cacheid |= CACHEID_VIPT_I_ALIASING;
 337	} else {
 338		cacheid = CACHEID_VIVT;
 339	}
 340
 341	pr_info("CPU: %s data cache, %s instruction cache\n",
 342		cache_is_vivt() ? "VIVT" :
 343		cache_is_vipt_aliasing() ? "VIPT aliasing" :
 344		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
 345		cache_is_vivt() ? "VIVT" :
 346		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
 347		icache_is_vipt_aliasing() ? "VIPT aliasing" :
 348		icache_is_pipt() ? "PIPT" :
 349		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
 350}
 351
 352/*
 353 * These functions re-use the assembly code in head.S, which
 354 * already provide the required functionality.
 355 */
 356extern struct proc_info_list *lookup_processor_type(unsigned int);
 357
 358void __init early_print(const char *str, ...)
 359{
 360	extern void printascii(const char *);
 361	char buf[256];
 362	va_list ap;
 363
 364	va_start(ap, str);
 365	vsnprintf(buf, sizeof(buf), str, ap);
 366	va_end(ap);
 367
 368#ifdef CONFIG_DEBUG_LL
 369	printascii(buf);
 370#endif
 371	printk("%s", buf);
 372}
 373
 374#ifdef CONFIG_ARM_PATCH_IDIV
 375
 376static inline u32 __attribute_const__ sdiv_instruction(void)
 377{
 378	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 379		/* "sdiv r0, r0, r1" */
 380		u32 insn = __opcode_thumb32_compose(0xfb90, 0xf0f1);
 381		return __opcode_to_mem_thumb32(insn);
 382	}
 383
 384	/* "sdiv r0, r0, r1" */
 385	return __opcode_to_mem_arm(0xe710f110);
 386}
 387
 388static inline u32 __attribute_const__ udiv_instruction(void)
 389{
 390	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 391		/* "udiv r0, r0, r1" */
 392		u32 insn = __opcode_thumb32_compose(0xfbb0, 0xf0f1);
 393		return __opcode_to_mem_thumb32(insn);
 394	}
 395
 396	/* "udiv r0, r0, r1" */
 397	return __opcode_to_mem_arm(0xe730f110);
 398}
 399
 400static inline u32 __attribute_const__ bx_lr_instruction(void)
 401{
 402	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 403		/* "bx lr; nop" */
 404		u32 insn = __opcode_thumb32_compose(0x4770, 0x46c0);
 405		return __opcode_to_mem_thumb32(insn);
 406	}
 407
 408	/* "bx lr" */
 409	return __opcode_to_mem_arm(0xe12fff1e);
 410}
 411
 412static void __init patch_aeabi_idiv(void)
 413{
 414	extern void __aeabi_uidiv(void);
 415	extern void __aeabi_idiv(void);
 416	uintptr_t fn_addr;
 417	unsigned int mask;
 418
 419	mask = IS_ENABLED(CONFIG_THUMB2_KERNEL) ? HWCAP_IDIVT : HWCAP_IDIVA;
 420	if (!(elf_hwcap & mask))
 421		return;
 422
 423	pr_info("CPU: div instructions available: patching division code\n");
 424
 425	fn_addr = ((uintptr_t)&__aeabi_uidiv) & ~1;
 426	asm ("" : "+g" (fn_addr));
 427	((u32 *)fn_addr)[0] = udiv_instruction();
 428	((u32 *)fn_addr)[1] = bx_lr_instruction();
 429	flush_icache_range(fn_addr, fn_addr + 8);
 430
 431	fn_addr = ((uintptr_t)&__aeabi_idiv) & ~1;
 432	asm ("" : "+g" (fn_addr));
 433	((u32 *)fn_addr)[0] = sdiv_instruction();
 434	((u32 *)fn_addr)[1] = bx_lr_instruction();
 435	flush_icache_range(fn_addr, fn_addr + 8);
 436}
 437
 438#else
 439static inline void patch_aeabi_idiv(void) { }
 440#endif
 441
 442static void __init cpuid_init_hwcaps(void)
 443{
 444	int block;
 445	u32 isar5;
 446	u32 isar6;
 447	u32 pfr2;
 448
 449	if (cpu_architecture() < CPU_ARCH_ARMv7)
 450		return;
 451
 452	block = cpuid_feature_extract(CPUID_EXT_ISAR0, 24);
 453	if (block >= 2)
 454		elf_hwcap |= HWCAP_IDIVA;
 455	if (block >= 1)
 456		elf_hwcap |= HWCAP_IDIVT;
 457
 458	/* LPAE implies atomic ldrd/strd instructions */
 459	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
 460	if (block >= 5)
 461		elf_hwcap |= HWCAP_LPAE;
 462
 463	/* check for supported v8 Crypto instructions */
 464	isar5 = read_cpuid_ext(CPUID_EXT_ISAR5);
 465
 466	block = cpuid_feature_extract_field(isar5, 4);
 467	if (block >= 2)
 468		elf_hwcap2 |= HWCAP2_PMULL;
 469	if (block >= 1)
 470		elf_hwcap2 |= HWCAP2_AES;
 471
 472	block = cpuid_feature_extract_field(isar5, 8);
 473	if (block >= 1)
 474		elf_hwcap2 |= HWCAP2_SHA1;
 475
 476	block = cpuid_feature_extract_field(isar5, 12);
 477	if (block >= 1)
 478		elf_hwcap2 |= HWCAP2_SHA2;
 479
 480	block = cpuid_feature_extract_field(isar5, 16);
 481	if (block >= 1)
 482		elf_hwcap2 |= HWCAP2_CRC32;
 483
 484	/* Check for Speculation barrier instruction */
 485	isar6 = read_cpuid_ext(CPUID_EXT_ISAR6);
 486	block = cpuid_feature_extract_field(isar6, 12);
 487	if (block >= 1)
 488		elf_hwcap2 |= HWCAP2_SB;
 489
 490	/* Check for Speculative Store Bypassing control */
 491	pfr2 = read_cpuid_ext(CPUID_EXT_PFR2);
 492	block = cpuid_feature_extract_field(pfr2, 4);
 493	if (block >= 1)
 494		elf_hwcap2 |= HWCAP2_SSBS;
 495}
 496
 497static void __init elf_hwcap_fixup(void)
 498{
 499	unsigned id = read_cpuid_id();
 500
 501	/*
 502	 * HWCAP_TLS is available only on 1136 r1p0 and later,
 503	 * see also kuser_get_tls_init.
 504	 */
 505	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
 506	    ((id >> 20) & 3) == 0) {
 507		elf_hwcap &= ~HWCAP_TLS;
 508		return;
 509	}
 510
 511	/* Verify if CPUID scheme is implemented */
 512	if ((id & 0x000f0000) != 0x000f0000)
 513		return;
 514
 515	/*
 516	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
 517	 * avoid advertising SWP; it may not be atomic with
 518	 * multiprocessing cores.
 519	 */
 520	if (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) > 1 ||
 521	    (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) == 1 &&
 522	     cpuid_feature_extract(CPUID_EXT_ISAR4, 20) >= 3))
 523		elf_hwcap &= ~HWCAP_SWP;
 524}
 525
 526/*
 527 * cpu_init - initialise one CPU.
 528 *
 529 * cpu_init sets up the per-CPU stacks.
 530 */
 531void notrace cpu_init(void)
 532{
 533#ifndef CONFIG_CPU_V7M
 534	unsigned int cpu = smp_processor_id();
 535	struct stack *stk = &stacks[cpu];
 536
 537	if (cpu >= NR_CPUS) {
 538		pr_crit("CPU%u: bad primary CPU number\n", cpu);
 539		BUG();
 540	}
 541
 542	/*
 543	 * This only works on resume and secondary cores. For booting on the
 544	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
 545	 */
 546	set_my_cpu_offset(per_cpu_offset(cpu));
 547
 548	cpu_proc_init();
 549
 550	/*
 551	 * Define the placement constraint for the inline asm directive below.
 552	 * In Thumb-2, msr with an immediate value is not allowed.
 553	 */
 554#ifdef CONFIG_THUMB2_KERNEL
 555#define PLC_l	"l"
 556#define PLC_r	"r"
 557#else
 558#define PLC_l	"I"
 559#define PLC_r	"I"
 560#endif
 561
 562	/*
 563	 * setup stacks for re-entrant exception handlers
 564	 */
 565	__asm__ (
 566	"msr	cpsr_c, %1\n\t"
 567	"add	r14, %0, %2\n\t"
 568	"mov	sp, r14\n\t"
 569	"msr	cpsr_c, %3\n\t"
 570	"add	r14, %0, %4\n\t"
 571	"mov	sp, r14\n\t"
 572	"msr	cpsr_c, %5\n\t"
 573	"add	r14, %0, %6\n\t"
 574	"mov	sp, r14\n\t"
 575	"msr	cpsr_c, %7\n\t"
 576	"add	r14, %0, %8\n\t"
 577	"mov	sp, r14\n\t"
 578	"msr	cpsr_c, %9"
 579	    :
 580	    : "r" (stk),
 581	      PLC_r (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
 582	      "I" (offsetof(struct stack, irq[0])),
 583	      PLC_r (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
 584	      "I" (offsetof(struct stack, abt[0])),
 585	      PLC_r (PSR_F_BIT | PSR_I_BIT | UND_MODE),
 586	      "I" (offsetof(struct stack, und[0])),
 587	      PLC_r (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
 588	      "I" (offsetof(struct stack, fiq[0])),
 589	      PLC_l (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
 590	    : "r14");
 591#endif
 592}
 593
 594u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
 595
 596void __init smp_setup_processor_id(void)
 597{
 598	int i;
 599	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
 600	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 601
 602	cpu_logical_map(0) = cpu;
 603	for (i = 1; i < nr_cpu_ids; ++i)
 604		cpu_logical_map(i) = i == cpu ? 0 : i;
 605
 606	/*
 607	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
 608	 * using percpu variable early, for example, lockdep will
 609	 * access percpu variable inside lock_release
 610	 */
 611	set_my_cpu_offset(0);
 612
 613	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
 614}
 615
 616struct mpidr_hash mpidr_hash;
 617#ifdef CONFIG_SMP
 618/**
 619 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
 620 *			  level in order to build a linear index from an
 621 *			  MPIDR value. Resulting algorithm is a collision
 622 *			  free hash carried out through shifting and ORing
 623 */
 624static void __init smp_build_mpidr_hash(void)
 625{
 626	u32 i, affinity;
 627	u32 fs[3], bits[3], ls, mask = 0;
 628	/*
 629	 * Pre-scan the list of MPIDRS and filter out bits that do
 630	 * not contribute to affinity levels, ie they never toggle.
 631	 */
 632	for_each_possible_cpu(i)
 633		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
 634	pr_debug("mask of set bits 0x%x\n", mask);
 635	/*
 636	 * Find and stash the last and first bit set at all affinity levels to
 637	 * check how many bits are required to represent them.
 638	 */
 639	for (i = 0; i < 3; i++) {
 640		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
 641		/*
 642		 * Find the MSB bit and LSB bits position
 643		 * to determine how many bits are required
 644		 * to express the affinity level.
 645		 */
 646		ls = fls(affinity);
 647		fs[i] = affinity ? ffs(affinity) - 1 : 0;
 648		bits[i] = ls - fs[i];
 649	}
 650	/*
 651	 * An index can be created from the MPIDR by isolating the
 652	 * significant bits at each affinity level and by shifting
 653	 * them in order to compress the 24 bits values space to a
 654	 * compressed set of values. This is equivalent to hashing
 655	 * the MPIDR through shifting and ORing. It is a collision free
 656	 * hash though not minimal since some levels might contain a number
 657	 * of CPUs that is not an exact power of 2 and their bit
 658	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
 659	 */
 660	mpidr_hash.shift_aff[0] = fs[0];
 661	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
 662	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
 663						(bits[1] + bits[0]);
 664	mpidr_hash.mask = mask;
 665	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
 666	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
 667				mpidr_hash.shift_aff[0],
 668				mpidr_hash.shift_aff[1],
 669				mpidr_hash.shift_aff[2],
 670				mpidr_hash.mask,
 671				mpidr_hash.bits);
 672	/*
 673	 * 4x is an arbitrary value used to warn on a hash table much bigger
 674	 * than expected on most systems.
 675	 */
 676	if (mpidr_hash_size() > 4 * num_possible_cpus())
 677		pr_warn("Large number of MPIDR hash buckets detected\n");
 678	sync_cache_w(&mpidr_hash);
 679}
 680#endif
 681
 682/*
 683 * locate processor in the list of supported processor types.  The linker
 684 * builds this table for us from the entries in arch/arm/mm/proc-*.S
 685 */
 686struct proc_info_list *lookup_processor(u32 midr)
 687{
 688	struct proc_info_list *list = lookup_processor_type(midr);
 689
 690	if (!list) {
 691		pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n",
 692		       smp_processor_id(), midr);
 693		while (1)
 694		/* can't use cpu_relax() here as it may require MMU setup */;
 695	}
 696
 697	return list;
 698}
 699
 700static void __init setup_processor(void)
 701{
 702	unsigned int midr = read_cpuid_id();
 703	struct proc_info_list *list = lookup_processor(midr);
 704
 705	cpu_name = list->cpu_name;
 706	__cpu_architecture = __get_cpu_architecture();
 707
 708	init_proc_vtable(list->proc);
 709#ifdef MULTI_TLB
 710	cpu_tlb = *list->tlb;
 711#endif
 712#ifdef MULTI_USER
 713	cpu_user = *list->user;
 714#endif
 715#ifdef MULTI_CACHE
 716	cpu_cache = *list->cache;
 717#endif
 718
 719	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
 720		list->cpu_name, midr, midr & 15,
 721		proc_arch[cpu_architecture()], get_cr());
 722
 723	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
 724		 list->arch_name, ENDIANNESS);
 725	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
 726		 list->elf_name, ENDIANNESS);
 727	elf_hwcap = list->elf_hwcap;
 728
 729	cpuid_init_hwcaps();
 730	patch_aeabi_idiv();
 731
 732#ifndef CONFIG_ARM_THUMB
 733	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
 734#endif
 735#ifdef CONFIG_MMU
 736	init_default_cache_policy(list->__cpu_mm_mmu_flags);
 737#endif
 738	erratum_a15_798181_init();
 739
 740	elf_hwcap_fixup();
 741
 742	cacheid_init();
 743	cpu_init();
 744}
 745
 746void __init dump_machine_table(void)
 747{
 748	const struct machine_desc *p;
 749
 750	early_print("Available machine support:\n\nID (hex)\tNAME\n");
 751	for_each_machine_desc(p)
 752		early_print("%08x\t%s\n", p->nr, p->name);
 753
 754	early_print("\nPlease check your kernel config and/or bootloader.\n");
 755
 756	while (true)
 757		/* can't use cpu_relax() here as it may require MMU setup */;
 758}
 759
 760int __init arm_add_memory(u64 start, u64 size)
 761{
 762	u64 aligned_start;
 763
 764	/*
 765	 * Ensure that start/size are aligned to a page boundary.
 766	 * Size is rounded down, start is rounded up.
 767	 */
 768	aligned_start = PAGE_ALIGN(start);
 769	if (aligned_start > start + size)
 770		size = 0;
 771	else
 772		size -= aligned_start - start;
 773
 774#ifndef CONFIG_PHYS_ADDR_T_64BIT
 775	if (aligned_start > ULONG_MAX) {
 776		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
 777			start);
 778		return -EINVAL;
 779	}
 780
 781	if (aligned_start + size > ULONG_MAX) {
 782		pr_crit("Truncating memory at 0x%08llx to fit in 32-bit physical address space\n",
 783			(long long)start);
 784		/*
 785		 * To ensure bank->start + bank->size is representable in
 786		 * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
 787		 * This means we lose a page after masking.
 788		 */
 789		size = ULONG_MAX - aligned_start;
 790	}
 791#endif
 792
 793	if (aligned_start < PHYS_OFFSET) {
 794		if (aligned_start + size <= PHYS_OFFSET) {
 795			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
 796				aligned_start, aligned_start + size);
 797			return -EINVAL;
 798		}
 799
 800		pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
 801			aligned_start, (u64)PHYS_OFFSET);
 802
 803		size -= PHYS_OFFSET - aligned_start;
 804		aligned_start = PHYS_OFFSET;
 805	}
 806
 807	start = aligned_start;
 808	size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
 809
 810	/*
 811	 * Check whether this memory region has non-zero size or
 812	 * invalid node number.
 813	 */
 814	if (size == 0)
 815		return -EINVAL;
 816
 817	memblock_add(start, size);
 818	return 0;
 819}
 820
 821/*
 822 * Pick out the memory size.  We look for mem=size@start,
 823 * where start and size are "size[KkMm]"
 824 */
 825
 826static int __init early_mem(char *p)
 827{
 828	static int usermem __initdata = 0;
 829	u64 size;
 830	u64 start;
 831	char *endp;
 832
 833	/*
 834	 * If the user specifies memory size, we
 835	 * blow away any automatically generated
 836	 * size.
 837	 */
 838	if (usermem == 0) {
 839		usermem = 1;
 840		memblock_remove(memblock_start_of_DRAM(),
 841			memblock_end_of_DRAM() - memblock_start_of_DRAM());
 842	}
 843
 844	start = PHYS_OFFSET;
 845	size  = memparse(p, &endp);
 846	if (*endp == '@')
 847		start = memparse(endp + 1, NULL);
 848
 849	arm_add_memory(start, size);
 850
 851	return 0;
 852}
 853early_param("mem", early_mem);
 854
 855static void __init request_standard_resources(const struct machine_desc *mdesc)
 856{
 857	phys_addr_t start, end, res_end;
 858	struct resource *res;
 859	u64 i;
 860
 861	kernel_code.start   = virt_to_phys(_text);
 862	kernel_code.end     = virt_to_phys(__init_begin - 1);
 863	kernel_data.start   = virt_to_phys(_sdata);
 864	kernel_data.end     = virt_to_phys(_end - 1);
 865
 866	for_each_mem_range(i, &start, &end) {
 867		unsigned long boot_alias_start;
 868
 869		/*
 870		 * In memblock, end points to the first byte after the
 871		 * range while in resourses, end points to the last byte in
 872		 * the range.
 873		 */
 874		res_end = end - 1;
 875
 876		/*
 877		 * Some systems have a special memory alias which is only
 878		 * used for booting.  We need to advertise this region to
 879		 * kexec-tools so they know where bootable RAM is located.
 880		 */
 881		boot_alias_start = phys_to_idmap(start);
 882		if (arm_has_idmap_alias() && boot_alias_start != IDMAP_INVALID_ADDR) {
 883			res = memblock_alloc_or_panic(sizeof(*res), SMP_CACHE_BYTES);
 884			res->name = "System RAM (boot alias)";
 885			res->start = boot_alias_start;
 886			res->end = phys_to_idmap(res_end);
 887			res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 888			request_resource(&iomem_resource, res);
 889		}
 890
 891		res = memblock_alloc_or_panic(sizeof(*res), SMP_CACHE_BYTES);
 892		res->name  = "System RAM";
 893		res->start = start;
 894		res->end = res_end;
 895		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 896
 897		request_resource(&iomem_resource, res);
 898
 899		if (kernel_code.start >= res->start &&
 900		    kernel_code.end <= res->end)
 901			request_resource(res, &kernel_code);
 902		if (kernel_data.start >= res->start &&
 903		    kernel_data.end <= res->end)
 904			request_resource(res, &kernel_data);
 905	}
 906
 907	if (mdesc->video_start) {
 908		video_ram.start = mdesc->video_start;
 909		video_ram.end   = mdesc->video_end;
 910		request_resource(&iomem_resource, &video_ram);
 911	}
 912
 913	/*
 914	 * Some machines don't have the possibility of ever
 915	 * possessing lp0, lp1 or lp2
 916	 */
 917	if (mdesc->reserve_lp0)
 918		request_resource(&ioport_resource, &lp0);
 919	if (mdesc->reserve_lp1)
 920		request_resource(&ioport_resource, &lp1);
 921	if (mdesc->reserve_lp2)
 922		request_resource(&ioport_resource, &lp2);
 923}
 924
 925#if defined(CONFIG_VGA_CONSOLE)
 926struct screen_info vgacon_screen_info = {
 927 .orig_video_lines	= 30,
 928 .orig_video_cols	= 80,
 929 .orig_video_mode	= 0,
 930 .orig_video_ega_bx	= 0,
 931 .orig_video_isVGA	= 1,
 932 .orig_video_points	= 8
 933};
 934#endif
 935
 936static int __init customize_machine(void)
 937{
 938	/*
 939	 * customizes platform devices, or adds new ones
 940	 * On DT based machines, we fall back to populating the
 941	 * machine from the device tree, if no callback is provided,
 942	 * otherwise we would always need an init_machine callback.
 943	 */
 944	if (machine_desc->init_machine)
 945		machine_desc->init_machine();
 946
 947	return 0;
 948}
 949arch_initcall(customize_machine);
 950
 951static int __init init_machine_late(void)
 952{
 953	struct device_node *root;
 954	int ret;
 955
 956	if (machine_desc->init_late)
 957		machine_desc->init_late();
 958
 959	root = of_find_node_by_path("/");
 960	if (root) {
 961		ret = of_property_read_string(root, "serial-number",
 962					      &system_serial);
 963		if (ret)
 964			system_serial = NULL;
 965	}
 966
 967	if (!system_serial)
 968		system_serial = kasprintf(GFP_KERNEL, "%08x%08x",
 969					  system_serial_high,
 970					  system_serial_low);
 971
 972	return 0;
 973}
 974late_initcall(init_machine_late);
 975
 976#ifdef CONFIG_CRASH_RESERVE
 977/*
 978 * The crash region must be aligned to 128MB to avoid
 979 * zImage relocating below the reserved region.
 980 */
 981#define CRASH_ALIGN	(128 << 20)
 982
 983static inline unsigned long long get_total_mem(void)
 984{
 985	unsigned long total;
 986
 987	total = max_low_pfn - min_low_pfn;
 988	return total << PAGE_SHIFT;
 989}
 990
 991/**
 992 * reserve_crashkernel() - reserves memory are for crash kernel
 993 *
 994 * This function reserves memory area given in "crashkernel=" kernel command
 995 * line parameter. The memory reserved is used by a dump capture kernel when
 996 * primary kernel is crashing.
 997 */
 998static void __init reserve_crashkernel(void)
 999{
1000	unsigned long long crash_size, crash_base;
1001	unsigned long long total_mem;
1002	int ret;
1003
1004	total_mem = get_total_mem();
1005	ret = parse_crashkernel(boot_command_line, total_mem,
1006				&crash_size, &crash_base,
1007				NULL, NULL, NULL);
1008	/* invalid value specified or crashkernel=0 */
1009	if (ret || !crash_size)
1010		return;
1011
1012	if (crash_base <= 0) {
1013		unsigned long long crash_max = idmap_to_phys((u32)~0);
1014		unsigned long long lowmem_max = __pa(high_memory - 1) + 1;
1015		if (crash_max > lowmem_max)
1016			crash_max = lowmem_max;
1017
1018		crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
1019						       CRASH_ALIGN, crash_max);
1020		if (!crash_base) {
1021			pr_err("crashkernel reservation failed - No suitable area found.\n");
1022			return;
1023		}
1024	} else {
1025		unsigned long long crash_max = crash_base + crash_size;
1026		unsigned long long start;
1027
1028		start = memblock_phys_alloc_range(crash_size, SECTION_SIZE,
1029						  crash_base, crash_max);
1030		if (!start) {
1031			pr_err("crashkernel reservation failed - memory is in use.\n");
1032			return;
1033		}
1034	}
1035
1036	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
1037		(unsigned long)(crash_size >> 20),
1038		(unsigned long)(crash_base >> 20),
1039		(unsigned long)(total_mem >> 20));
1040
1041	/* The crashk resource must always be located in normal mem */
1042	crashk_res.start = crash_base;
1043	crashk_res.end = crash_base + crash_size - 1;
1044	insert_resource(&iomem_resource, &crashk_res);
1045
1046	if (arm_has_idmap_alias()) {
1047		/*
1048		 * If we have a special RAM alias for use at boot, we
1049		 * need to advertise to kexec tools where the alias is.
1050		 */
1051		static struct resource crashk_boot_res = {
1052			.name = "Crash kernel (boot alias)",
1053			.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
1054		};
1055
1056		crashk_boot_res.start = phys_to_idmap(crash_base);
1057		crashk_boot_res.end = crashk_boot_res.start + crash_size - 1;
1058		insert_resource(&iomem_resource, &crashk_boot_res);
1059	}
1060}
1061#else
1062static inline void reserve_crashkernel(void) {}
1063#endif /* CONFIG_CRASH_RESERVE*/
1064
1065void __init hyp_mode_check(void)
1066{
1067#ifdef CONFIG_ARM_VIRT_EXT
1068	sync_boot_mode();
1069
1070	if (is_hyp_mode_available()) {
1071		pr_info("CPU: All CPU(s) started in HYP mode.\n");
1072		pr_info("CPU: Virtualization extensions available.\n");
1073	} else if (is_hyp_mode_mismatched()) {
1074		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
1075			__boot_cpu_mode & MODE_MASK);
1076		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
1077	} else
1078		pr_info("CPU: All CPU(s) started in SVC mode.\n");
1079#endif
1080}
1081
1082static void (*__arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
1083
1084static int arm_restart(struct notifier_block *nb, unsigned long action,
1085		       void *data)
1086{
1087	__arm_pm_restart(action, data);
1088	return NOTIFY_DONE;
1089}
1090
1091static struct notifier_block arm_restart_nb = {
1092	.notifier_call = arm_restart,
1093	.priority = 128,
1094};
1095
1096void __init setup_arch(char **cmdline_p)
1097{
1098	const struct machine_desc *mdesc = NULL;
1099	void *atags_vaddr = NULL;
1100
1101	if (__atags_pointer)
1102		atags_vaddr = FDT_VIRT_BASE(__atags_pointer);
1103
1104	setup_processor();
1105	if (atags_vaddr) {
1106		mdesc = setup_machine_fdt(atags_vaddr);
1107		if (mdesc)
1108			memblock_reserve(__atags_pointer,
1109					 fdt_totalsize(atags_vaddr));
1110	}
1111	if (!mdesc)
1112		mdesc = setup_machine_tags(atags_vaddr, __machine_arch_type);
1113	if (!mdesc) {
1114		early_print("\nError: invalid dtb and unrecognized/unsupported machine ID\n");
1115		early_print("  r1=0x%08x, r2=0x%08x\n", __machine_arch_type,
1116			    __atags_pointer);
1117		if (__atags_pointer)
1118			early_print("  r2[]=%*ph\n", 16, atags_vaddr);
1119		dump_machine_table();
1120	}
1121
1122	machine_desc = mdesc;
1123	machine_name = mdesc->name;
1124	dump_stack_set_arch_desc("%s", mdesc->name);
1125
1126	if (mdesc->reboot_mode != REBOOT_HARD)
1127		reboot_mode = mdesc->reboot_mode;
1128
1129	setup_initial_init_mm(_text, _etext, _edata, _end);
1130
1131	/* populate cmd_line too for later use, preserving boot_command_line */
1132	strscpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
1133	*cmdline_p = cmd_line;
1134
1135	early_fixmap_init();
1136	early_ioremap_init();
1137
1138	parse_early_param();
1139
1140#ifdef CONFIG_MMU
1141	early_mm_init(mdesc);
1142#endif
1143	setup_dma_zone(mdesc);
1144	xen_early_init();
1145	arm_efi_init();
1146	/*
1147	 * Make sure the calculation for lowmem/highmem is set appropriately
1148	 * before reserving/allocating any memory
1149	 */
1150	adjust_lowmem_bounds();
1151	arm_memblock_init(mdesc);
1152	/* Memory may have been removed so recalculate the bounds. */
1153	adjust_lowmem_bounds();
1154
1155	early_ioremap_reset();
1156
1157	paging_init(mdesc);
1158	kasan_init();
1159	request_standard_resources(mdesc);
1160
1161	if (mdesc->restart) {
1162		__arm_pm_restart = mdesc->restart;
1163		register_restart_handler(&arm_restart_nb);
1164	}
1165
1166	unflatten_device_tree();
1167
1168	arm_dt_init_cpu_maps();
1169	psci_dt_init();
1170#ifdef CONFIG_SMP
1171	if (is_smp()) {
1172		if (!mdesc->smp_init || !mdesc->smp_init()) {
1173			if (psci_smp_available())
1174				smp_set_ops(&psci_smp_ops);
1175			else if (mdesc->smp)
1176				smp_set_ops(mdesc->smp);
1177		}
1178		smp_init_cpus();
1179		smp_build_mpidr_hash();
1180	}
1181#endif
1182
1183	if (!is_smp())
1184		hyp_mode_check();
1185
1186	reserve_crashkernel();
1187
1188#ifdef CONFIG_VT
1189#if defined(CONFIG_VGA_CONSOLE)
1190	vgacon_register_screen(&vgacon_screen_info);
1191#endif
1192#endif
1193
1194	if (mdesc->init_early)
1195		mdesc->init_early();
1196}
1197
1198bool arch_cpu_is_hotpluggable(int num)
1199{
1200	return platform_can_hotplug_cpu(num);
1201}
1202
1203#ifdef CONFIG_HAVE_PROC_CPU
1204static int __init proc_cpu_init(void)
1205{
1206	struct proc_dir_entry *res;
1207
1208	res = proc_mkdir("cpu", NULL);
1209	if (!res)
1210		return -ENOMEM;
1211	return 0;
1212}
1213fs_initcall(proc_cpu_init);
1214#endif
1215
1216static const char *hwcap_str[] = {
1217	"swp",
1218	"half",
1219	"thumb",
1220	"26bit",
1221	"fastmult",
1222	"fpa",
1223	"vfp",
1224	"edsp",
1225	"java",
1226	"iwmmxt",
1227	"crunch",
1228	"thumbee",
1229	"neon",
1230	"vfpv3",
1231	"vfpv3d16",
1232	"tls",
1233	"vfpv4",
1234	"idiva",
1235	"idivt",
1236	"vfpd32",
1237	"lpae",
1238	"evtstrm",
1239	"fphp",
1240	"asimdhp",
1241	"asimddp",
1242	"asimdfhm",
1243	"asimdbf16",
1244	"i8mm",
1245	NULL
1246};
1247
1248static const char *hwcap2_str[] = {
1249	"aes",
1250	"pmull",
1251	"sha1",
1252	"sha2",
1253	"crc32",
1254	"sb",
1255	"ssbs",
1256	NULL
1257};
1258
1259static int c_show(struct seq_file *m, void *v)
1260{
1261	int i, j;
1262	u32 cpuid;
1263
1264	for_each_online_cpu(i) {
1265		/*
1266		 * glibc reads /proc/cpuinfo to determine the number of
1267		 * online processors, looking for lines beginning with
1268		 * "processor".  Give glibc what it expects.
1269		 */
1270		seq_printf(m, "processor\t: %d\n", i);
1271		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1272		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1273			   cpu_name, cpuid & 15, elf_platform);
1274
1275#if defined(CONFIG_SMP)
1276		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1277			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1278			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1279#else
1280		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1281			   loops_per_jiffy / (500000/HZ),
1282			   (loops_per_jiffy / (5000/HZ)) % 100);
1283#endif
1284		/* dump out the processor features */
1285		seq_puts(m, "Features\t: ");
1286
1287		for (j = 0; hwcap_str[j]; j++)
1288			if (elf_hwcap & (1 << j))
1289				seq_printf(m, "%s ", hwcap_str[j]);
1290
1291		for (j = 0; hwcap2_str[j]; j++)
1292			if (elf_hwcap2 & (1 << j))
1293				seq_printf(m, "%s ", hwcap2_str[j]);
1294
1295		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1296		seq_printf(m, "CPU architecture: %s\n",
1297			   proc_arch[cpu_architecture()]);
1298
1299		if ((cpuid & 0x0008f000) == 0x00000000) {
1300			/* pre-ARM7 */
1301			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1302		} else {
1303			if ((cpuid & 0x0008f000) == 0x00007000) {
1304				/* ARM7 */
1305				seq_printf(m, "CPU variant\t: 0x%02x\n",
1306					   (cpuid >> 16) & 127);
1307			} else {
1308				/* post-ARM7 */
1309				seq_printf(m, "CPU variant\t: 0x%x\n",
1310					   (cpuid >> 20) & 15);
1311			}
1312			seq_printf(m, "CPU part\t: 0x%03x\n",
1313				   (cpuid >> 4) & 0xfff);
1314		}
1315		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1316	}
1317
1318	seq_printf(m, "Hardware\t: %s\n", machine_name);
1319	seq_printf(m, "Revision\t: %04x\n", system_rev);
1320	seq_printf(m, "Serial\t\t: %s\n", system_serial);
1321
1322	return 0;
1323}
1324
1325static void *c_start(struct seq_file *m, loff_t *pos)
1326{
1327	return *pos < 1 ? (void *)1 : NULL;
1328}
1329
1330static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1331{
1332	++*pos;
1333	return NULL;
1334}
1335
1336static void c_stop(struct seq_file *m, void *v)
1337{
1338}
1339
1340const struct seq_operations cpuinfo_op = {
1341	.start	= c_start,
1342	.next	= c_next,
1343	.stop	= c_stop,
1344	.show	= c_show
1345};
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