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v6.13.7
   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(sizeof(*res), SMP_CACHE_BYTES);
 884			if (!res)
 885				panic("%s: Failed to allocate %zu bytes\n",
 886				      __func__, sizeof(*res));
 887			res->name = "System RAM (boot alias)";
 888			res->start = boot_alias_start;
 889			res->end = phys_to_idmap(res_end);
 890			res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 891			request_resource(&iomem_resource, res);
 892		}
 893
 894		res = memblock_alloc(sizeof(*res), SMP_CACHE_BYTES);
 895		if (!res)
 896			panic("%s: Failed to allocate %zu bytes\n", __func__,
 897			      sizeof(*res));
 898		res->name  = "System RAM";
 899		res->start = start;
 900		res->end = res_end;
 901		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 902
 903		request_resource(&iomem_resource, res);
 904
 905		if (kernel_code.start >= res->start &&
 906		    kernel_code.end <= res->end)
 907			request_resource(res, &kernel_code);
 908		if (kernel_data.start >= res->start &&
 909		    kernel_data.end <= res->end)
 910			request_resource(res, &kernel_data);
 911	}
 912
 913	if (mdesc->video_start) {
 914		video_ram.start = mdesc->video_start;
 915		video_ram.end   = mdesc->video_end;
 916		request_resource(&iomem_resource, &video_ram);
 917	}
 918
 919	/*
 920	 * Some machines don't have the possibility of ever
 921	 * possessing lp0, lp1 or lp2
 922	 */
 923	if (mdesc->reserve_lp0)
 924		request_resource(&ioport_resource, &lp0);
 925	if (mdesc->reserve_lp1)
 926		request_resource(&ioport_resource, &lp1);
 927	if (mdesc->reserve_lp2)
 928		request_resource(&ioport_resource, &lp2);
 929}
 930
 931#if defined(CONFIG_VGA_CONSOLE)
 932struct screen_info vgacon_screen_info = {
 
 933 .orig_video_lines	= 30,
 934 .orig_video_cols	= 80,
 935 .orig_video_mode	= 0,
 936 .orig_video_ega_bx	= 0,
 937 .orig_video_isVGA	= 1,
 938 .orig_video_points	= 8
 939};
 940#endif
 941
 942static int __init customize_machine(void)
 943{
 944	/*
 945	 * customizes platform devices, or adds new ones
 946	 * On DT based machines, we fall back to populating the
 947	 * machine from the device tree, if no callback is provided,
 948	 * otherwise we would always need an init_machine callback.
 949	 */
 950	if (machine_desc->init_machine)
 951		machine_desc->init_machine();
 952
 953	return 0;
 954}
 955arch_initcall(customize_machine);
 956
 957static int __init init_machine_late(void)
 958{
 959	struct device_node *root;
 960	int ret;
 961
 962	if (machine_desc->init_late)
 963		machine_desc->init_late();
 964
 965	root = of_find_node_by_path("/");
 966	if (root) {
 967		ret = of_property_read_string(root, "serial-number",
 968					      &system_serial);
 969		if (ret)
 970			system_serial = NULL;
 971	}
 972
 973	if (!system_serial)
 974		system_serial = kasprintf(GFP_KERNEL, "%08x%08x",
 975					  system_serial_high,
 976					  system_serial_low);
 977
 978	return 0;
 979}
 980late_initcall(init_machine_late);
 981
 982#ifdef CONFIG_CRASH_RESERVE
 983/*
 984 * The crash region must be aligned to 128MB to avoid
 985 * zImage relocating below the reserved region.
 986 */
 987#define CRASH_ALIGN	(128 << 20)
 988
 989static inline unsigned long long get_total_mem(void)
 990{
 991	unsigned long total;
 992
 993	total = max_low_pfn - min_low_pfn;
 994	return total << PAGE_SHIFT;
 995}
 996
 997/**
 998 * reserve_crashkernel() - reserves memory are for crash kernel
 999 *
1000 * This function reserves memory area given in "crashkernel=" kernel command
1001 * line parameter. The memory reserved is used by a dump capture kernel when
1002 * primary kernel is crashing.
1003 */
1004static void __init reserve_crashkernel(void)
1005{
1006	unsigned long long crash_size, crash_base;
1007	unsigned long long total_mem;
1008	int ret;
1009
1010	total_mem = get_total_mem();
1011	ret = parse_crashkernel(boot_command_line, total_mem,
1012				&crash_size, &crash_base,
1013				NULL, NULL);
1014	/* invalid value specified or crashkernel=0 */
1015	if (ret || !crash_size)
1016		return;
1017
1018	if (crash_base <= 0) {
1019		unsigned long long crash_max = idmap_to_phys((u32)~0);
1020		unsigned long long lowmem_max = __pa(high_memory - 1) + 1;
1021		if (crash_max > lowmem_max)
1022			crash_max = lowmem_max;
1023
1024		crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
1025						       CRASH_ALIGN, crash_max);
1026		if (!crash_base) {
1027			pr_err("crashkernel reservation failed - No suitable area found.\n");
1028			return;
1029		}
1030	} else {
1031		unsigned long long crash_max = crash_base + crash_size;
1032		unsigned long long start;
1033
1034		start = memblock_phys_alloc_range(crash_size, SECTION_SIZE,
1035						  crash_base, crash_max);
1036		if (!start) {
 
1037			pr_err("crashkernel reservation failed - memory is in use.\n");
1038			return;
1039		}
1040	}
1041
 
 
 
 
 
 
 
1042	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
1043		(unsigned long)(crash_size >> 20),
1044		(unsigned long)(crash_base >> 20),
1045		(unsigned long)(total_mem >> 20));
1046
1047	/* The crashk resource must always be located in normal mem */
1048	crashk_res.start = crash_base;
1049	crashk_res.end = crash_base + crash_size - 1;
1050	insert_resource(&iomem_resource, &crashk_res);
1051
1052	if (arm_has_idmap_alias()) {
1053		/*
1054		 * If we have a special RAM alias for use at boot, we
1055		 * need to advertise to kexec tools where the alias is.
1056		 */
1057		static struct resource crashk_boot_res = {
1058			.name = "Crash kernel (boot alias)",
1059			.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
1060		};
1061
1062		crashk_boot_res.start = phys_to_idmap(crash_base);
1063		crashk_boot_res.end = crashk_boot_res.start + crash_size - 1;
1064		insert_resource(&iomem_resource, &crashk_boot_res);
1065	}
1066}
1067#else
1068static inline void reserve_crashkernel(void) {}
1069#endif /* CONFIG_CRASH_RESERVE*/
1070
1071void __init hyp_mode_check(void)
1072{
1073#ifdef CONFIG_ARM_VIRT_EXT
1074	sync_boot_mode();
1075
1076	if (is_hyp_mode_available()) {
1077		pr_info("CPU: All CPU(s) started in HYP mode.\n");
1078		pr_info("CPU: Virtualization extensions available.\n");
1079	} else if (is_hyp_mode_mismatched()) {
1080		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
1081			__boot_cpu_mode & MODE_MASK);
1082		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
1083	} else
1084		pr_info("CPU: All CPU(s) started in SVC mode.\n");
1085#endif
1086}
1087
1088static void (*__arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
1089
1090static int arm_restart(struct notifier_block *nb, unsigned long action,
1091		       void *data)
1092{
1093	__arm_pm_restart(action, data);
1094	return NOTIFY_DONE;
1095}
1096
1097static struct notifier_block arm_restart_nb = {
1098	.notifier_call = arm_restart,
1099	.priority = 128,
1100};
1101
1102void __init setup_arch(char **cmdline_p)
1103{
1104	const struct machine_desc *mdesc = NULL;
1105	void *atags_vaddr = NULL;
1106
1107	if (__atags_pointer)
1108		atags_vaddr = FDT_VIRT_BASE(__atags_pointer);
1109
1110	setup_processor();
1111	if (atags_vaddr) {
1112		mdesc = setup_machine_fdt(atags_vaddr);
1113		if (mdesc)
1114			memblock_reserve(__atags_pointer,
1115					 fdt_totalsize(atags_vaddr));
1116	}
1117	if (!mdesc)
1118		mdesc = setup_machine_tags(atags_vaddr, __machine_arch_type);
1119	if (!mdesc) {
1120		early_print("\nError: invalid dtb and unrecognized/unsupported machine ID\n");
1121		early_print("  r1=0x%08x, r2=0x%08x\n", __machine_arch_type,
1122			    __atags_pointer);
1123		if (__atags_pointer)
1124			early_print("  r2[]=%*ph\n", 16, atags_vaddr);
 
1125		dump_machine_table();
1126	}
1127
1128	machine_desc = mdesc;
1129	machine_name = mdesc->name;
1130	dump_stack_set_arch_desc("%s", mdesc->name);
1131
1132	if (mdesc->reboot_mode != REBOOT_HARD)
1133		reboot_mode = mdesc->reboot_mode;
1134
1135	setup_initial_init_mm(_text, _etext, _edata, _end);
 
 
 
1136
1137	/* populate cmd_line too for later use, preserving boot_command_line */
1138	strscpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
1139	*cmdline_p = cmd_line;
1140
1141	early_fixmap_init();
1142	early_ioremap_init();
1143
1144	parse_early_param();
1145
1146#ifdef CONFIG_MMU
1147	early_mm_init(mdesc);
1148#endif
1149	setup_dma_zone(mdesc);
1150	xen_early_init();
1151	arm_efi_init();
1152	/*
1153	 * Make sure the calculation for lowmem/highmem is set appropriately
1154	 * before reserving/allocating any memory
1155	 */
1156	adjust_lowmem_bounds();
1157	arm_memblock_init(mdesc);
1158	/* Memory may have been removed so recalculate the bounds. */
1159	adjust_lowmem_bounds();
1160
1161	early_ioremap_reset();
1162
1163	paging_init(mdesc);
1164	kasan_init();
1165	request_standard_resources(mdesc);
1166
1167	if (mdesc->restart) {
1168		__arm_pm_restart = mdesc->restart;
1169		register_restart_handler(&arm_restart_nb);
1170	}
1171
1172	unflatten_device_tree();
1173
1174	arm_dt_init_cpu_maps();
1175	psci_dt_init();
1176#ifdef CONFIG_SMP
1177	if (is_smp()) {
1178		if (!mdesc->smp_init || !mdesc->smp_init()) {
1179			if (psci_smp_available())
1180				smp_set_ops(&psci_smp_ops);
1181			else if (mdesc->smp)
1182				smp_set_ops(mdesc->smp);
1183		}
1184		smp_init_cpus();
1185		smp_build_mpidr_hash();
1186	}
1187#endif
1188
1189	if (!is_smp())
1190		hyp_mode_check();
1191
1192	reserve_crashkernel();
1193
 
 
 
 
1194#ifdef CONFIG_VT
1195#if defined(CONFIG_VGA_CONSOLE)
1196	vgacon_register_screen(&vgacon_screen_info);
 
 
1197#endif
1198#endif
1199
1200	if (mdesc->init_early)
1201		mdesc->init_early();
1202}
1203
1204bool arch_cpu_is_hotpluggable(int num)
 
1205{
1206	return platform_can_hotplug_cpu(num);
 
 
 
 
 
 
 
 
1207}
 
1208
1209#ifdef CONFIG_HAVE_PROC_CPU
1210static int __init proc_cpu_init(void)
1211{
1212	struct proc_dir_entry *res;
1213
1214	res = proc_mkdir("cpu", NULL);
1215	if (!res)
1216		return -ENOMEM;
1217	return 0;
1218}
1219fs_initcall(proc_cpu_init);
1220#endif
1221
1222static const char *hwcap_str[] = {
1223	"swp",
1224	"half",
1225	"thumb",
1226	"26bit",
1227	"fastmult",
1228	"fpa",
1229	"vfp",
1230	"edsp",
1231	"java",
1232	"iwmmxt",
1233	"crunch",
1234	"thumbee",
1235	"neon",
1236	"vfpv3",
1237	"vfpv3d16",
1238	"tls",
1239	"vfpv4",
1240	"idiva",
1241	"idivt",
1242	"vfpd32",
1243	"lpae",
1244	"evtstrm",
1245	"fphp",
1246	"asimdhp",
1247	"asimddp",
1248	"asimdfhm",
1249	"asimdbf16",
1250	"i8mm",
1251	NULL
1252};
1253
1254static const char *hwcap2_str[] = {
1255	"aes",
1256	"pmull",
1257	"sha1",
1258	"sha2",
1259	"crc32",
1260	"sb",
1261	"ssbs",
1262	NULL
1263};
1264
1265static int c_show(struct seq_file *m, void *v)
1266{
1267	int i, j;
1268	u32 cpuid;
1269
1270	for_each_online_cpu(i) {
1271		/*
1272		 * glibc reads /proc/cpuinfo to determine the number of
1273		 * online processors, looking for lines beginning with
1274		 * "processor".  Give glibc what it expects.
1275		 */
1276		seq_printf(m, "processor\t: %d\n", i);
1277		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1278		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1279			   cpu_name, cpuid & 15, elf_platform);
1280
1281#if defined(CONFIG_SMP)
1282		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1283			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1284			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1285#else
1286		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1287			   loops_per_jiffy / (500000/HZ),
1288			   (loops_per_jiffy / (5000/HZ)) % 100);
1289#endif
1290		/* dump out the processor features */
1291		seq_puts(m, "Features\t: ");
1292
1293		for (j = 0; hwcap_str[j]; j++)
1294			if (elf_hwcap & (1 << j))
1295				seq_printf(m, "%s ", hwcap_str[j]);
1296
1297		for (j = 0; hwcap2_str[j]; j++)
1298			if (elf_hwcap2 & (1 << j))
1299				seq_printf(m, "%s ", hwcap2_str[j]);
1300
1301		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1302		seq_printf(m, "CPU architecture: %s\n",
1303			   proc_arch[cpu_architecture()]);
1304
1305		if ((cpuid & 0x0008f000) == 0x00000000) {
1306			/* pre-ARM7 */
1307			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1308		} else {
1309			if ((cpuid & 0x0008f000) == 0x00007000) {
1310				/* ARM7 */
1311				seq_printf(m, "CPU variant\t: 0x%02x\n",
1312					   (cpuid >> 16) & 127);
1313			} else {
1314				/* post-ARM7 */
1315				seq_printf(m, "CPU variant\t: 0x%x\n",
1316					   (cpuid >> 20) & 15);
1317			}
1318			seq_printf(m, "CPU part\t: 0x%03x\n",
1319				   (cpuid >> 4) & 0xfff);
1320		}
1321		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1322	}
1323
1324	seq_printf(m, "Hardware\t: %s\n", machine_name);
1325	seq_printf(m, "Revision\t: %04x\n", system_rev);
1326	seq_printf(m, "Serial\t\t: %s\n", system_serial);
1327
1328	return 0;
1329}
1330
1331static void *c_start(struct seq_file *m, loff_t *pos)
1332{
1333	return *pos < 1 ? (void *)1 : NULL;
1334}
1335
1336static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1337{
1338	++*pos;
1339	return NULL;
1340}
1341
1342static void c_stop(struct seq_file *m, void *v)
1343{
1344}
1345
1346const struct seq_operations cpuinfo_op = {
1347	.start	= c_start,
1348	.next	= c_next,
1349	.stop	= c_stop,
1350	.show	= c_show
1351};
v4.17
 
   1/*
   2 *  linux/arch/arm/kernel/setup.c
   3 *
   4 *  Copyright (C) 1995-2001 Russell King
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10#include <linux/efi.h>
  11#include <linux/export.h>
  12#include <linux/kernel.h>
  13#include <linux/stddef.h>
  14#include <linux/ioport.h>
  15#include <linux/delay.h>
  16#include <linux/utsname.h>
  17#include <linux/initrd.h>
  18#include <linux/console.h>
  19#include <linux/bootmem.h>
  20#include <linux/seq_file.h>
  21#include <linux/screen_info.h>
  22#include <linux/of_platform.h>
  23#include <linux/init.h>
  24#include <linux/kexec.h>
 
 
  25#include <linux/of_fdt.h>
  26#include <linux/cpu.h>
  27#include <linux/interrupt.h>
  28#include <linux/smp.h>
  29#include <linux/proc_fs.h>
  30#include <linux/memblock.h>
  31#include <linux/bug.h>
  32#include <linux/compiler.h>
  33#include <linux/sort.h>
  34#include <linux/psci.h>
  35
  36#include <asm/unified.h>
  37#include <asm/cp15.h>
  38#include <asm/cpu.h>
  39#include <asm/cputype.h>
  40#include <asm/efi.h>
  41#include <asm/elf.h>
  42#include <asm/early_ioremap.h>
  43#include <asm/fixmap.h>
  44#include <asm/procinfo.h>
  45#include <asm/psci.h>
  46#include <asm/sections.h>
  47#include <asm/setup.h>
  48#include <asm/smp_plat.h>
  49#include <asm/mach-types.h>
  50#include <asm/cacheflush.h>
  51#include <asm/cachetype.h>
  52#include <asm/tlbflush.h>
  53#include <asm/xen/hypervisor.h>
  54
  55#include <asm/prom.h>
  56#include <asm/mach/arch.h>
  57#include <asm/mach/irq.h>
  58#include <asm/mach/time.h>
  59#include <asm/system_info.h>
  60#include <asm/system_misc.h>
  61#include <asm/traps.h>
  62#include <asm/unwind.h>
  63#include <asm/memblock.h>
  64#include <asm/virt.h>
 
  65
  66#include "atags.h"
  67
  68
  69#if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
  70char fpe_type[8];
  71
  72static int __init fpe_setup(char *line)
  73{
  74	memcpy(fpe_type, line, 8);
  75	return 1;
  76}
  77
  78__setup("fpe=", fpe_setup);
  79#endif
  80
  81extern void init_default_cache_policy(unsigned long);
  82extern void paging_init(const struct machine_desc *desc);
  83extern void early_mm_init(const struct machine_desc *);
  84extern void adjust_lowmem_bounds(void);
  85extern enum reboot_mode reboot_mode;
  86extern void setup_dma_zone(const struct machine_desc *desc);
  87
  88unsigned int processor_id;
  89EXPORT_SYMBOL(processor_id);
  90unsigned int __machine_arch_type __read_mostly;
  91EXPORT_SYMBOL(__machine_arch_type);
  92unsigned int cacheid __read_mostly;
  93EXPORT_SYMBOL(cacheid);
  94
  95unsigned int __atags_pointer __initdata;
  96
  97unsigned int system_rev;
  98EXPORT_SYMBOL(system_rev);
  99
 100const char *system_serial;
 101EXPORT_SYMBOL(system_serial);
 102
 103unsigned int system_serial_low;
 104EXPORT_SYMBOL(system_serial_low);
 105
 106unsigned int system_serial_high;
 107EXPORT_SYMBOL(system_serial_high);
 108
 109unsigned int elf_hwcap __read_mostly;
 110EXPORT_SYMBOL(elf_hwcap);
 111
 112unsigned int elf_hwcap2 __read_mostly;
 113EXPORT_SYMBOL(elf_hwcap2);
 114
 115
 116#ifdef MULTI_CPU
 117struct processor processor __ro_after_init;
 
 
 
 
 
 118#endif
 119#ifdef MULTI_TLB
 120struct cpu_tlb_fns cpu_tlb __ro_after_init;
 121#endif
 122#ifdef MULTI_USER
 123struct cpu_user_fns cpu_user __ro_after_init;
 124#endif
 125#ifdef MULTI_CACHE
 126struct cpu_cache_fns cpu_cache __ro_after_init;
 127#endif
 128#ifdef CONFIG_OUTER_CACHE
 129struct outer_cache_fns outer_cache __ro_after_init;
 130EXPORT_SYMBOL(outer_cache);
 131#endif
 132
 133/*
 134 * Cached cpu_architecture() result for use by assembler code.
 135 * C code should use the cpu_architecture() function instead of accessing this
 136 * variable directly.
 137 */
 138int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
 139
 140struct stack {
 141	u32 irq[3];
 142	u32 abt[3];
 143	u32 und[3];
 144	u32 fiq[3];
 145} ____cacheline_aligned;
 146
 147#ifndef CONFIG_CPU_V7M
 148static struct stack stacks[NR_CPUS];
 149#endif
 150
 151char elf_platform[ELF_PLATFORM_SIZE];
 152EXPORT_SYMBOL(elf_platform);
 153
 154static const char *cpu_name;
 155static const char *machine_name;
 156static char __initdata cmd_line[COMMAND_LINE_SIZE];
 157const struct machine_desc *machine_desc __initdata;
 158
 159static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
 160#define ENDIANNESS ((char)endian_test.l)
 161
 162DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
 163
 164/*
 165 * Standard memory resources
 166 */
 167static struct resource mem_res[] = {
 168	{
 169		.name = "Video RAM",
 170		.start = 0,
 171		.end = 0,
 172		.flags = IORESOURCE_MEM
 173	},
 174	{
 175		.name = "Kernel code",
 176		.start = 0,
 177		.end = 0,
 178		.flags = IORESOURCE_SYSTEM_RAM
 179	},
 180	{
 181		.name = "Kernel data",
 182		.start = 0,
 183		.end = 0,
 184		.flags = IORESOURCE_SYSTEM_RAM
 185	}
 186};
 187
 188#define video_ram   mem_res[0]
 189#define kernel_code mem_res[1]
 190#define kernel_data mem_res[2]
 191
 192static struct resource io_res[] = {
 193	{
 194		.name = "reserved",
 195		.start = 0x3bc,
 196		.end = 0x3be,
 197		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 198	},
 199	{
 200		.name = "reserved",
 201		.start = 0x378,
 202		.end = 0x37f,
 203		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 204	},
 205	{
 206		.name = "reserved",
 207		.start = 0x278,
 208		.end = 0x27f,
 209		.flags = IORESOURCE_IO | IORESOURCE_BUSY
 210	}
 211};
 212
 213#define lp0 io_res[0]
 214#define lp1 io_res[1]
 215#define lp2 io_res[2]
 216
 217static const char *proc_arch[] = {
 218	"undefined/unknown",
 219	"3",
 220	"4",
 221	"4T",
 222	"5",
 223	"5T",
 224	"5TE",
 225	"5TEJ",
 226	"6TEJ",
 227	"7",
 228	"7M",
 229	"?(12)",
 230	"?(13)",
 231	"?(14)",
 232	"?(15)",
 233	"?(16)",
 234	"?(17)",
 235};
 236
 237#ifdef CONFIG_CPU_V7M
 238static int __get_cpu_architecture(void)
 239{
 240	return CPU_ARCH_ARMv7M;
 241}
 242#else
 243static int __get_cpu_architecture(void)
 244{
 245	int cpu_arch;
 246
 247	if ((read_cpuid_id() & 0x0008f000) == 0) {
 248		cpu_arch = CPU_ARCH_UNKNOWN;
 249	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
 250		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
 251	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
 252		cpu_arch = (read_cpuid_id() >> 16) & 7;
 253		if (cpu_arch)
 254			cpu_arch += CPU_ARCH_ARMv3;
 255	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
 256		/* Revised CPUID format. Read the Memory Model Feature
 257		 * Register 0 and check for VMSAv7 or PMSAv7 */
 258		unsigned int mmfr0 = read_cpuid_ext(CPUID_EXT_MMFR0);
 259		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
 260		    (mmfr0 & 0x000000f0) >= 0x00000030)
 261			cpu_arch = CPU_ARCH_ARMv7;
 262		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
 263			 (mmfr0 & 0x000000f0) == 0x00000020)
 264			cpu_arch = CPU_ARCH_ARMv6;
 265		else
 266			cpu_arch = CPU_ARCH_UNKNOWN;
 267	} else
 268		cpu_arch = CPU_ARCH_UNKNOWN;
 269
 270	return cpu_arch;
 271}
 272#endif
 273
 274int __pure cpu_architecture(void)
 275{
 276	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
 277
 278	return __cpu_architecture;
 279}
 280
 281static int cpu_has_aliasing_icache(unsigned int arch)
 282{
 283	int aliasing_icache;
 284	unsigned int id_reg, num_sets, line_size;
 285
 286	/* PIPT caches never alias. */
 287	if (icache_is_pipt())
 288		return 0;
 289
 290	/* arch specifies the register format */
 291	switch (arch) {
 292	case CPU_ARCH_ARMv7:
 293		set_csselr(CSSELR_ICACHE | CSSELR_L1);
 294		isb();
 295		id_reg = read_ccsidr();
 296		line_size = 4 << ((id_reg & 0x7) + 2);
 297		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
 298		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
 299		break;
 300	case CPU_ARCH_ARMv6:
 301		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
 302		break;
 303	default:
 304		/* I-cache aliases will be handled by D-cache aliasing code */
 305		aliasing_icache = 0;
 306	}
 307
 308	return aliasing_icache;
 309}
 310
 311static void __init cacheid_init(void)
 312{
 313	unsigned int arch = cpu_architecture();
 314
 315	if (arch >= CPU_ARCH_ARMv6) {
 316		unsigned int cachetype = read_cpuid_cachetype();
 317
 318		if ((arch == CPU_ARCH_ARMv7M) && !(cachetype & 0xf000f)) {
 319			cacheid = 0;
 320		} else if ((cachetype & (7 << 29)) == 4 << 29) {
 321			/* ARMv7 register format */
 322			arch = CPU_ARCH_ARMv7;
 323			cacheid = CACHEID_VIPT_NONALIASING;
 324			switch (cachetype & (3 << 14)) {
 325			case (1 << 14):
 326				cacheid |= CACHEID_ASID_TAGGED;
 327				break;
 328			case (3 << 14):
 329				cacheid |= CACHEID_PIPT;
 330				break;
 331			}
 332		} else {
 333			arch = CPU_ARCH_ARMv6;
 334			if (cachetype & (1 << 23))
 335				cacheid = CACHEID_VIPT_ALIASING;
 336			else
 337				cacheid = CACHEID_VIPT_NONALIASING;
 338		}
 339		if (cpu_has_aliasing_icache(arch))
 340			cacheid |= CACHEID_VIPT_I_ALIASING;
 341	} else {
 342		cacheid = CACHEID_VIVT;
 343	}
 344
 345	pr_info("CPU: %s data cache, %s instruction cache\n",
 346		cache_is_vivt() ? "VIVT" :
 347		cache_is_vipt_aliasing() ? "VIPT aliasing" :
 348		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
 349		cache_is_vivt() ? "VIVT" :
 350		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
 351		icache_is_vipt_aliasing() ? "VIPT aliasing" :
 352		icache_is_pipt() ? "PIPT" :
 353		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
 354}
 355
 356/*
 357 * These functions re-use the assembly code in head.S, which
 358 * already provide the required functionality.
 359 */
 360extern struct proc_info_list *lookup_processor_type(unsigned int);
 361
 362void __init early_print(const char *str, ...)
 363{
 364	extern void printascii(const char *);
 365	char buf[256];
 366	va_list ap;
 367
 368	va_start(ap, str);
 369	vsnprintf(buf, sizeof(buf), str, ap);
 370	va_end(ap);
 371
 372#ifdef CONFIG_DEBUG_LL
 373	printascii(buf);
 374#endif
 375	printk("%s", buf);
 376}
 377
 378#ifdef CONFIG_ARM_PATCH_IDIV
 379
 380static inline u32 __attribute_const__ sdiv_instruction(void)
 381{
 382	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 383		/* "sdiv r0, r0, r1" */
 384		u32 insn = __opcode_thumb32_compose(0xfb90, 0xf0f1);
 385		return __opcode_to_mem_thumb32(insn);
 386	}
 387
 388	/* "sdiv r0, r0, r1" */
 389	return __opcode_to_mem_arm(0xe710f110);
 390}
 391
 392static inline u32 __attribute_const__ udiv_instruction(void)
 393{
 394	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 395		/* "udiv r0, r0, r1" */
 396		u32 insn = __opcode_thumb32_compose(0xfbb0, 0xf0f1);
 397		return __opcode_to_mem_thumb32(insn);
 398	}
 399
 400	/* "udiv r0, r0, r1" */
 401	return __opcode_to_mem_arm(0xe730f110);
 402}
 403
 404static inline u32 __attribute_const__ bx_lr_instruction(void)
 405{
 406	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
 407		/* "bx lr; nop" */
 408		u32 insn = __opcode_thumb32_compose(0x4770, 0x46c0);
 409		return __opcode_to_mem_thumb32(insn);
 410	}
 411
 412	/* "bx lr" */
 413	return __opcode_to_mem_arm(0xe12fff1e);
 414}
 415
 416static void __init patch_aeabi_idiv(void)
 417{
 418	extern void __aeabi_uidiv(void);
 419	extern void __aeabi_idiv(void);
 420	uintptr_t fn_addr;
 421	unsigned int mask;
 422
 423	mask = IS_ENABLED(CONFIG_THUMB2_KERNEL) ? HWCAP_IDIVT : HWCAP_IDIVA;
 424	if (!(elf_hwcap & mask))
 425		return;
 426
 427	pr_info("CPU: div instructions available: patching division code\n");
 428
 429	fn_addr = ((uintptr_t)&__aeabi_uidiv) & ~1;
 430	asm ("" : "+g" (fn_addr));
 431	((u32 *)fn_addr)[0] = udiv_instruction();
 432	((u32 *)fn_addr)[1] = bx_lr_instruction();
 433	flush_icache_range(fn_addr, fn_addr + 8);
 434
 435	fn_addr = ((uintptr_t)&__aeabi_idiv) & ~1;
 436	asm ("" : "+g" (fn_addr));
 437	((u32 *)fn_addr)[0] = sdiv_instruction();
 438	((u32 *)fn_addr)[1] = bx_lr_instruction();
 439	flush_icache_range(fn_addr, fn_addr + 8);
 440}
 441
 442#else
 443static inline void patch_aeabi_idiv(void) { }
 444#endif
 445
 446static void __init cpuid_init_hwcaps(void)
 447{
 448	int block;
 449	u32 isar5;
 
 
 450
 451	if (cpu_architecture() < CPU_ARCH_ARMv7)
 452		return;
 453
 454	block = cpuid_feature_extract(CPUID_EXT_ISAR0, 24);
 455	if (block >= 2)
 456		elf_hwcap |= HWCAP_IDIVA;
 457	if (block >= 1)
 458		elf_hwcap |= HWCAP_IDIVT;
 459
 460	/* LPAE implies atomic ldrd/strd instructions */
 461	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
 462	if (block >= 5)
 463		elf_hwcap |= HWCAP_LPAE;
 464
 465	/* check for supported v8 Crypto instructions */
 466	isar5 = read_cpuid_ext(CPUID_EXT_ISAR5);
 467
 468	block = cpuid_feature_extract_field(isar5, 4);
 469	if (block >= 2)
 470		elf_hwcap2 |= HWCAP2_PMULL;
 471	if (block >= 1)
 472		elf_hwcap2 |= HWCAP2_AES;
 473
 474	block = cpuid_feature_extract_field(isar5, 8);
 475	if (block >= 1)
 476		elf_hwcap2 |= HWCAP2_SHA1;
 477
 478	block = cpuid_feature_extract_field(isar5, 12);
 479	if (block >= 1)
 480		elf_hwcap2 |= HWCAP2_SHA2;
 481
 482	block = cpuid_feature_extract_field(isar5, 16);
 483	if (block >= 1)
 484		elf_hwcap2 |= HWCAP2_CRC32;
 
 
 
 
 
 
 
 
 
 
 
 
 485}
 486
 487static void __init elf_hwcap_fixup(void)
 488{
 489	unsigned id = read_cpuid_id();
 490
 491	/*
 492	 * HWCAP_TLS is available only on 1136 r1p0 and later,
 493	 * see also kuser_get_tls_init.
 494	 */
 495	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
 496	    ((id >> 20) & 3) == 0) {
 497		elf_hwcap &= ~HWCAP_TLS;
 498		return;
 499	}
 500
 501	/* Verify if CPUID scheme is implemented */
 502	if ((id & 0x000f0000) != 0x000f0000)
 503		return;
 504
 505	/*
 506	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
 507	 * avoid advertising SWP; it may not be atomic with
 508	 * multiprocessing cores.
 509	 */
 510	if (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) > 1 ||
 511	    (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) == 1 &&
 512	     cpuid_feature_extract(CPUID_EXT_ISAR4, 20) >= 3))
 513		elf_hwcap &= ~HWCAP_SWP;
 514}
 515
 516/*
 517 * cpu_init - initialise one CPU.
 518 *
 519 * cpu_init sets up the per-CPU stacks.
 520 */
 521void notrace cpu_init(void)
 522{
 523#ifndef CONFIG_CPU_V7M
 524	unsigned int cpu = smp_processor_id();
 525	struct stack *stk = &stacks[cpu];
 526
 527	if (cpu >= NR_CPUS) {
 528		pr_crit("CPU%u: bad primary CPU number\n", cpu);
 529		BUG();
 530	}
 531
 532	/*
 533	 * This only works on resume and secondary cores. For booting on the
 534	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
 535	 */
 536	set_my_cpu_offset(per_cpu_offset(cpu));
 537
 538	cpu_proc_init();
 539
 540	/*
 541	 * Define the placement constraint for the inline asm directive below.
 542	 * In Thumb-2, msr with an immediate value is not allowed.
 543	 */
 544#ifdef CONFIG_THUMB2_KERNEL
 545#define PLC	"r"
 
 546#else
 547#define PLC	"I"
 
 548#endif
 549
 550	/*
 551	 * setup stacks for re-entrant exception handlers
 552	 */
 553	__asm__ (
 554	"msr	cpsr_c, %1\n\t"
 555	"add	r14, %0, %2\n\t"
 556	"mov	sp, r14\n\t"
 557	"msr	cpsr_c, %3\n\t"
 558	"add	r14, %0, %4\n\t"
 559	"mov	sp, r14\n\t"
 560	"msr	cpsr_c, %5\n\t"
 561	"add	r14, %0, %6\n\t"
 562	"mov	sp, r14\n\t"
 563	"msr	cpsr_c, %7\n\t"
 564	"add	r14, %0, %8\n\t"
 565	"mov	sp, r14\n\t"
 566	"msr	cpsr_c, %9"
 567	    :
 568	    : "r" (stk),
 569	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
 570	      "I" (offsetof(struct stack, irq[0])),
 571	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
 572	      "I" (offsetof(struct stack, abt[0])),
 573	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
 574	      "I" (offsetof(struct stack, und[0])),
 575	      PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
 576	      "I" (offsetof(struct stack, fiq[0])),
 577	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
 578	    : "r14");
 579#endif
 580}
 581
 582u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
 583
 584void __init smp_setup_processor_id(void)
 585{
 586	int i;
 587	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
 588	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 589
 590	cpu_logical_map(0) = cpu;
 591	for (i = 1; i < nr_cpu_ids; ++i)
 592		cpu_logical_map(i) = i == cpu ? 0 : i;
 593
 594	/*
 595	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
 596	 * using percpu variable early, for example, lockdep will
 597	 * access percpu variable inside lock_release
 598	 */
 599	set_my_cpu_offset(0);
 600
 601	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
 602}
 603
 604struct mpidr_hash mpidr_hash;
 605#ifdef CONFIG_SMP
 606/**
 607 * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
 608 *			  level in order to build a linear index from an
 609 *			  MPIDR value. Resulting algorithm is a collision
 610 *			  free hash carried out through shifting and ORing
 611 */
 612static void __init smp_build_mpidr_hash(void)
 613{
 614	u32 i, affinity;
 615	u32 fs[3], bits[3], ls, mask = 0;
 616	/*
 617	 * Pre-scan the list of MPIDRS and filter out bits that do
 618	 * not contribute to affinity levels, ie they never toggle.
 619	 */
 620	for_each_possible_cpu(i)
 621		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
 622	pr_debug("mask of set bits 0x%x\n", mask);
 623	/*
 624	 * Find and stash the last and first bit set at all affinity levels to
 625	 * check how many bits are required to represent them.
 626	 */
 627	for (i = 0; i < 3; i++) {
 628		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
 629		/*
 630		 * Find the MSB bit and LSB bits position
 631		 * to determine how many bits are required
 632		 * to express the affinity level.
 633		 */
 634		ls = fls(affinity);
 635		fs[i] = affinity ? ffs(affinity) - 1 : 0;
 636		bits[i] = ls - fs[i];
 637	}
 638	/*
 639	 * An index can be created from the MPIDR by isolating the
 640	 * significant bits at each affinity level and by shifting
 641	 * them in order to compress the 24 bits values space to a
 642	 * compressed set of values. This is equivalent to hashing
 643	 * the MPIDR through shifting and ORing. It is a collision free
 644	 * hash though not minimal since some levels might contain a number
 645	 * of CPUs that is not an exact power of 2 and their bit
 646	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
 647	 */
 648	mpidr_hash.shift_aff[0] = fs[0];
 649	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
 650	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
 651						(bits[1] + bits[0]);
 652	mpidr_hash.mask = mask;
 653	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
 654	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
 655				mpidr_hash.shift_aff[0],
 656				mpidr_hash.shift_aff[1],
 657				mpidr_hash.shift_aff[2],
 658				mpidr_hash.mask,
 659				mpidr_hash.bits);
 660	/*
 661	 * 4x is an arbitrary value used to warn on a hash table much bigger
 662	 * than expected on most systems.
 663	 */
 664	if (mpidr_hash_size() > 4 * num_possible_cpus())
 665		pr_warn("Large number of MPIDR hash buckets detected\n");
 666	sync_cache_w(&mpidr_hash);
 667}
 668#endif
 669
 670static void __init setup_processor(void)
 
 
 
 
 671{
 672	struct proc_info_list *list;
 673
 674	/*
 675	 * locate processor in the list of supported processor
 676	 * types.  The linker builds this table for us from the
 677	 * entries in arch/arm/mm/proc-*.S
 678	 */
 679	list = lookup_processor_type(read_cpuid_id());
 680	if (!list) {
 681		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
 682		       read_cpuid_id());
 683		while (1);
 
 684	}
 685
 
 
 
 
 
 
 
 
 686	cpu_name = list->cpu_name;
 687	__cpu_architecture = __get_cpu_architecture();
 688
 689#ifdef MULTI_CPU
 690	processor = *list->proc;
 691#endif
 692#ifdef MULTI_TLB
 693	cpu_tlb = *list->tlb;
 694#endif
 695#ifdef MULTI_USER
 696	cpu_user = *list->user;
 697#endif
 698#ifdef MULTI_CACHE
 699	cpu_cache = *list->cache;
 700#endif
 701
 702	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
 703		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
 704		proc_arch[cpu_architecture()], get_cr());
 705
 706	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
 707		 list->arch_name, ENDIANNESS);
 708	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
 709		 list->elf_name, ENDIANNESS);
 710	elf_hwcap = list->elf_hwcap;
 711
 712	cpuid_init_hwcaps();
 713	patch_aeabi_idiv();
 714
 715#ifndef CONFIG_ARM_THUMB
 716	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
 717#endif
 718#ifdef CONFIG_MMU
 719	init_default_cache_policy(list->__cpu_mm_mmu_flags);
 720#endif
 721	erratum_a15_798181_init();
 722
 723	elf_hwcap_fixup();
 724
 725	cacheid_init();
 726	cpu_init();
 727}
 728
 729void __init dump_machine_table(void)
 730{
 731	const struct machine_desc *p;
 732
 733	early_print("Available machine support:\n\nID (hex)\tNAME\n");
 734	for_each_machine_desc(p)
 735		early_print("%08x\t%s\n", p->nr, p->name);
 736
 737	early_print("\nPlease check your kernel config and/or bootloader.\n");
 738
 739	while (true)
 740		/* can't use cpu_relax() here as it may require MMU setup */;
 741}
 742
 743int __init arm_add_memory(u64 start, u64 size)
 744{
 745	u64 aligned_start;
 746
 747	/*
 748	 * Ensure that start/size are aligned to a page boundary.
 749	 * Size is rounded down, start is rounded up.
 750	 */
 751	aligned_start = PAGE_ALIGN(start);
 752	if (aligned_start > start + size)
 753		size = 0;
 754	else
 755		size -= aligned_start - start;
 756
 757#ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
 758	if (aligned_start > ULONG_MAX) {
 759		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
 760			(long long)start);
 761		return -EINVAL;
 762	}
 763
 764	if (aligned_start + size > ULONG_MAX) {
 765		pr_crit("Truncating memory at 0x%08llx to fit in 32-bit physical address space\n",
 766			(long long)start);
 767		/*
 768		 * To ensure bank->start + bank->size is representable in
 769		 * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
 770		 * This means we lose a page after masking.
 771		 */
 772		size = ULONG_MAX - aligned_start;
 773	}
 774#endif
 775
 776	if (aligned_start < PHYS_OFFSET) {
 777		if (aligned_start + size <= PHYS_OFFSET) {
 778			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
 779				aligned_start, aligned_start + size);
 780			return -EINVAL;
 781		}
 782
 783		pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
 784			aligned_start, (u64)PHYS_OFFSET);
 785
 786		size -= PHYS_OFFSET - aligned_start;
 787		aligned_start = PHYS_OFFSET;
 788	}
 789
 790	start = aligned_start;
 791	size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
 792
 793	/*
 794	 * Check whether this memory region has non-zero size or
 795	 * invalid node number.
 796	 */
 797	if (size == 0)
 798		return -EINVAL;
 799
 800	memblock_add(start, size);
 801	return 0;
 802}
 803
 804/*
 805 * Pick out the memory size.  We look for mem=size@start,
 806 * where start and size are "size[KkMm]"
 807 */
 808
 809static int __init early_mem(char *p)
 810{
 811	static int usermem __initdata = 0;
 812	u64 size;
 813	u64 start;
 814	char *endp;
 815
 816	/*
 817	 * If the user specifies memory size, we
 818	 * blow away any automatically generated
 819	 * size.
 820	 */
 821	if (usermem == 0) {
 822		usermem = 1;
 823		memblock_remove(memblock_start_of_DRAM(),
 824			memblock_end_of_DRAM() - memblock_start_of_DRAM());
 825	}
 826
 827	start = PHYS_OFFSET;
 828	size  = memparse(p, &endp);
 829	if (*endp == '@')
 830		start = memparse(endp + 1, NULL);
 831
 832	arm_add_memory(start, size);
 833
 834	return 0;
 835}
 836early_param("mem", early_mem);
 837
 838static void __init request_standard_resources(const struct machine_desc *mdesc)
 839{
 840	struct memblock_region *region;
 841	struct resource *res;
 
 842
 843	kernel_code.start   = virt_to_phys(_text);
 844	kernel_code.end     = virt_to_phys(__init_begin - 1);
 845	kernel_data.start   = virt_to_phys(_sdata);
 846	kernel_data.end     = virt_to_phys(_end - 1);
 847
 848	for_each_memblock(memory, region) {
 849		phys_addr_t start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 850		phys_addr_t end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 851		unsigned long boot_alias_start;
 852
 853		/*
 
 
 
 
 
 
 
 854		 * Some systems have a special memory alias which is only
 855		 * used for booting.  We need to advertise this region to
 856		 * kexec-tools so they know where bootable RAM is located.
 857		 */
 858		boot_alias_start = phys_to_idmap(start);
 859		if (arm_has_idmap_alias() && boot_alias_start != IDMAP_INVALID_ADDR) {
 860			res = memblock_virt_alloc(sizeof(*res), 0);
 
 
 
 861			res->name = "System RAM (boot alias)";
 862			res->start = boot_alias_start;
 863			res->end = phys_to_idmap(end);
 864			res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 865			request_resource(&iomem_resource, res);
 866		}
 867
 868		res = memblock_virt_alloc(sizeof(*res), 0);
 
 
 
 869		res->name  = "System RAM";
 870		res->start = start;
 871		res->end = end;
 872		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 873
 874		request_resource(&iomem_resource, res);
 875
 876		if (kernel_code.start >= res->start &&
 877		    kernel_code.end <= res->end)
 878			request_resource(res, &kernel_code);
 879		if (kernel_data.start >= res->start &&
 880		    kernel_data.end <= res->end)
 881			request_resource(res, &kernel_data);
 882	}
 883
 884	if (mdesc->video_start) {
 885		video_ram.start = mdesc->video_start;
 886		video_ram.end   = mdesc->video_end;
 887		request_resource(&iomem_resource, &video_ram);
 888	}
 889
 890	/*
 891	 * Some machines don't have the possibility of ever
 892	 * possessing lp0, lp1 or lp2
 893	 */
 894	if (mdesc->reserve_lp0)
 895		request_resource(&ioport_resource, &lp0);
 896	if (mdesc->reserve_lp1)
 897		request_resource(&ioport_resource, &lp1);
 898	if (mdesc->reserve_lp2)
 899		request_resource(&ioport_resource, &lp2);
 900}
 901
 902#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE) || \
 903    defined(CONFIG_EFI)
 904struct screen_info screen_info = {
 905 .orig_video_lines	= 30,
 906 .orig_video_cols	= 80,
 907 .orig_video_mode	= 0,
 908 .orig_video_ega_bx	= 0,
 909 .orig_video_isVGA	= 1,
 910 .orig_video_points	= 8
 911};
 912#endif
 913
 914static int __init customize_machine(void)
 915{
 916	/*
 917	 * customizes platform devices, or adds new ones
 918	 * On DT based machines, we fall back to populating the
 919	 * machine from the device tree, if no callback is provided,
 920	 * otherwise we would always need an init_machine callback.
 921	 */
 922	if (machine_desc->init_machine)
 923		machine_desc->init_machine();
 924
 925	return 0;
 926}
 927arch_initcall(customize_machine);
 928
 929static int __init init_machine_late(void)
 930{
 931	struct device_node *root;
 932	int ret;
 933
 934	if (machine_desc->init_late)
 935		machine_desc->init_late();
 936
 937	root = of_find_node_by_path("/");
 938	if (root) {
 939		ret = of_property_read_string(root, "serial-number",
 940					      &system_serial);
 941		if (ret)
 942			system_serial = NULL;
 943	}
 944
 945	if (!system_serial)
 946		system_serial = kasprintf(GFP_KERNEL, "%08x%08x",
 947					  system_serial_high,
 948					  system_serial_low);
 949
 950	return 0;
 951}
 952late_initcall(init_machine_late);
 953
 954#ifdef CONFIG_KEXEC
 955/*
 956 * The crash region must be aligned to 128MB to avoid
 957 * zImage relocating below the reserved region.
 958 */
 959#define CRASH_ALIGN	(128 << 20)
 960
 961static inline unsigned long long get_total_mem(void)
 962{
 963	unsigned long total;
 964
 965	total = max_low_pfn - min_low_pfn;
 966	return total << PAGE_SHIFT;
 967}
 968
 969/**
 970 * reserve_crashkernel() - reserves memory are for crash kernel
 971 *
 972 * This function reserves memory area given in "crashkernel=" kernel command
 973 * line parameter. The memory reserved is used by a dump capture kernel when
 974 * primary kernel is crashing.
 975 */
 976static void __init reserve_crashkernel(void)
 977{
 978	unsigned long long crash_size, crash_base;
 979	unsigned long long total_mem;
 980	int ret;
 981
 982	total_mem = get_total_mem();
 983	ret = parse_crashkernel(boot_command_line, total_mem,
 984				&crash_size, &crash_base);
 985	if (ret)
 
 
 986		return;
 987
 988	if (crash_base <= 0) {
 989		unsigned long long crash_max = idmap_to_phys((u32)~0);
 990		unsigned long long lowmem_max = __pa(high_memory - 1) + 1;
 991		if (crash_max > lowmem_max)
 992			crash_max = lowmem_max;
 993		crash_base = memblock_find_in_range(CRASH_ALIGN, crash_max,
 994						    crash_size, CRASH_ALIGN);
 
 995		if (!crash_base) {
 996			pr_err("crashkernel reservation failed - No suitable area found.\n");
 997			return;
 998		}
 999	} else {
 
1000		unsigned long long start;
1001
1002		start = memblock_find_in_range(crash_base,
1003					       crash_base + crash_size,
1004					       crash_size, SECTION_SIZE);
1005		if (start != crash_base) {
1006			pr_err("crashkernel reservation failed - memory is in use.\n");
1007			return;
1008		}
1009	}
1010
1011	ret = memblock_reserve(crash_base, crash_size);
1012	if (ret < 0) {
1013		pr_warn("crashkernel reservation failed - memory is in use (0x%lx)\n",
1014			(unsigned long)crash_base);
1015		return;
1016	}
1017
1018	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
1019		(unsigned long)(crash_size >> 20),
1020		(unsigned long)(crash_base >> 20),
1021		(unsigned long)(total_mem >> 20));
1022
1023	/* The crashk resource must always be located in normal mem */
1024	crashk_res.start = crash_base;
1025	crashk_res.end = crash_base + crash_size - 1;
1026	insert_resource(&iomem_resource, &crashk_res);
1027
1028	if (arm_has_idmap_alias()) {
1029		/*
1030		 * If we have a special RAM alias for use at boot, we
1031		 * need to advertise to kexec tools where the alias is.
1032		 */
1033		static struct resource crashk_boot_res = {
1034			.name = "Crash kernel (boot alias)",
1035			.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
1036		};
1037
1038		crashk_boot_res.start = phys_to_idmap(crash_base);
1039		crashk_boot_res.end = crashk_boot_res.start + crash_size - 1;
1040		insert_resource(&iomem_resource, &crashk_boot_res);
1041	}
1042}
1043#else
1044static inline void reserve_crashkernel(void) {}
1045#endif /* CONFIG_KEXEC */
1046
1047void __init hyp_mode_check(void)
1048{
1049#ifdef CONFIG_ARM_VIRT_EXT
1050	sync_boot_mode();
1051
1052	if (is_hyp_mode_available()) {
1053		pr_info("CPU: All CPU(s) started in HYP mode.\n");
1054		pr_info("CPU: Virtualization extensions available.\n");
1055	} else if (is_hyp_mode_mismatched()) {
1056		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
1057			__boot_cpu_mode & MODE_MASK);
1058		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
1059	} else
1060		pr_info("CPU: All CPU(s) started in SVC mode.\n");
1061#endif
1062}
1063
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1064void __init setup_arch(char **cmdline_p)
1065{
1066	const struct machine_desc *mdesc;
 
 
 
 
1067
1068	setup_processor();
1069	mdesc = setup_machine_fdt(__atags_pointer);
 
 
 
 
 
1070	if (!mdesc)
1071		mdesc = setup_machine_tags(__atags_pointer, __machine_arch_type);
1072	if (!mdesc) {
1073		early_print("\nError: invalid dtb and unrecognized/unsupported machine ID\n");
1074		early_print("  r1=0x%08x, r2=0x%08x\n", __machine_arch_type,
1075			    __atags_pointer);
1076		if (__atags_pointer)
1077			early_print("  r2[]=%*ph\n", 16,
1078				    phys_to_virt(__atags_pointer));
1079		dump_machine_table();
1080	}
1081
1082	machine_desc = mdesc;
1083	machine_name = mdesc->name;
1084	dump_stack_set_arch_desc("%s", mdesc->name);
1085
1086	if (mdesc->reboot_mode != REBOOT_HARD)
1087		reboot_mode = mdesc->reboot_mode;
1088
1089	init_mm.start_code = (unsigned long) _text;
1090	init_mm.end_code   = (unsigned long) _etext;
1091	init_mm.end_data   = (unsigned long) _edata;
1092	init_mm.brk	   = (unsigned long) _end;
1093
1094	/* populate cmd_line too for later use, preserving boot_command_line */
1095	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
1096	*cmdline_p = cmd_line;
1097
1098	early_fixmap_init();
1099	early_ioremap_init();
1100
1101	parse_early_param();
1102
1103#ifdef CONFIG_MMU
1104	early_mm_init(mdesc);
1105#endif
1106	setup_dma_zone(mdesc);
1107	xen_early_init();
1108	efi_init();
1109	/*
1110	 * Make sure the calculation for lowmem/highmem is set appropriately
1111	 * before reserving/allocating any mmeory
1112	 */
1113	adjust_lowmem_bounds();
1114	arm_memblock_init(mdesc);
1115	/* Memory may have been removed so recalculate the bounds. */
1116	adjust_lowmem_bounds();
1117
1118	early_ioremap_reset();
1119
1120	paging_init(mdesc);
 
1121	request_standard_resources(mdesc);
1122
1123	if (mdesc->restart)
1124		arm_pm_restart = mdesc->restart;
 
 
1125
1126	unflatten_device_tree();
1127
1128	arm_dt_init_cpu_maps();
1129	psci_dt_init();
1130#ifdef CONFIG_SMP
1131	if (is_smp()) {
1132		if (!mdesc->smp_init || !mdesc->smp_init()) {
1133			if (psci_smp_available())
1134				smp_set_ops(&psci_smp_ops);
1135			else if (mdesc->smp)
1136				smp_set_ops(mdesc->smp);
1137		}
1138		smp_init_cpus();
1139		smp_build_mpidr_hash();
1140	}
1141#endif
1142
1143	if (!is_smp())
1144		hyp_mode_check();
1145
1146	reserve_crashkernel();
1147
1148#ifdef CONFIG_MULTI_IRQ_HANDLER
1149	handle_arch_irq = mdesc->handle_irq;
1150#endif
1151
1152#ifdef CONFIG_VT
1153#if defined(CONFIG_VGA_CONSOLE)
1154	conswitchp = &vga_con;
1155#elif defined(CONFIG_DUMMY_CONSOLE)
1156	conswitchp = &dummy_con;
1157#endif
1158#endif
1159
1160	if (mdesc->init_early)
1161		mdesc->init_early();
1162}
1163
1164
1165static int __init topology_init(void)
1166{
1167	int cpu;
1168
1169	for_each_possible_cpu(cpu) {
1170		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
1171		cpuinfo->cpu.hotpluggable = platform_can_hotplug_cpu(cpu);
1172		register_cpu(&cpuinfo->cpu, cpu);
1173	}
1174
1175	return 0;
1176}
1177subsys_initcall(topology_init);
1178
1179#ifdef CONFIG_HAVE_PROC_CPU
1180static int __init proc_cpu_init(void)
1181{
1182	struct proc_dir_entry *res;
1183
1184	res = proc_mkdir("cpu", NULL);
1185	if (!res)
1186		return -ENOMEM;
1187	return 0;
1188}
1189fs_initcall(proc_cpu_init);
1190#endif
1191
1192static const char *hwcap_str[] = {
1193	"swp",
1194	"half",
1195	"thumb",
1196	"26bit",
1197	"fastmult",
1198	"fpa",
1199	"vfp",
1200	"edsp",
1201	"java",
1202	"iwmmxt",
1203	"crunch",
1204	"thumbee",
1205	"neon",
1206	"vfpv3",
1207	"vfpv3d16",
1208	"tls",
1209	"vfpv4",
1210	"idiva",
1211	"idivt",
1212	"vfpd32",
1213	"lpae",
1214	"evtstrm",
 
 
 
 
 
 
1215	NULL
1216};
1217
1218static const char *hwcap2_str[] = {
1219	"aes",
1220	"pmull",
1221	"sha1",
1222	"sha2",
1223	"crc32",
 
 
1224	NULL
1225};
1226
1227static int c_show(struct seq_file *m, void *v)
1228{
1229	int i, j;
1230	u32 cpuid;
1231
1232	for_each_online_cpu(i) {
1233		/*
1234		 * glibc reads /proc/cpuinfo to determine the number of
1235		 * online processors, looking for lines beginning with
1236		 * "processor".  Give glibc what it expects.
1237		 */
1238		seq_printf(m, "processor\t: %d\n", i);
1239		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1240		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1241			   cpu_name, cpuid & 15, elf_platform);
1242
1243#if defined(CONFIG_SMP)
1244		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1245			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1246			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1247#else
1248		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1249			   loops_per_jiffy / (500000/HZ),
1250			   (loops_per_jiffy / (5000/HZ)) % 100);
1251#endif
1252		/* dump out the processor features */
1253		seq_puts(m, "Features\t: ");
1254
1255		for (j = 0; hwcap_str[j]; j++)
1256			if (elf_hwcap & (1 << j))
1257				seq_printf(m, "%s ", hwcap_str[j]);
1258
1259		for (j = 0; hwcap2_str[j]; j++)
1260			if (elf_hwcap2 & (1 << j))
1261				seq_printf(m, "%s ", hwcap2_str[j]);
1262
1263		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1264		seq_printf(m, "CPU architecture: %s\n",
1265			   proc_arch[cpu_architecture()]);
1266
1267		if ((cpuid & 0x0008f000) == 0x00000000) {
1268			/* pre-ARM7 */
1269			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1270		} else {
1271			if ((cpuid & 0x0008f000) == 0x00007000) {
1272				/* ARM7 */
1273				seq_printf(m, "CPU variant\t: 0x%02x\n",
1274					   (cpuid >> 16) & 127);
1275			} else {
1276				/* post-ARM7 */
1277				seq_printf(m, "CPU variant\t: 0x%x\n",
1278					   (cpuid >> 20) & 15);
1279			}
1280			seq_printf(m, "CPU part\t: 0x%03x\n",
1281				   (cpuid >> 4) & 0xfff);
1282		}
1283		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1284	}
1285
1286	seq_printf(m, "Hardware\t: %s\n", machine_name);
1287	seq_printf(m, "Revision\t: %04x\n", system_rev);
1288	seq_printf(m, "Serial\t\t: %s\n", system_serial);
1289
1290	return 0;
1291}
1292
1293static void *c_start(struct seq_file *m, loff_t *pos)
1294{
1295	return *pos < 1 ? (void *)1 : NULL;
1296}
1297
1298static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1299{
1300	++*pos;
1301	return NULL;
1302}
1303
1304static void c_stop(struct seq_file *m, void *v)
1305{
1306}
1307
1308const struct seq_operations cpuinfo_op = {
1309	.start	= c_start,
1310	.next	= c_next,
1311	.stop	= c_stop,
1312	.show	= c_show
1313};