common.c 28.5 KB
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#include <linux/init.h>
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#include <linux/kernel.h>
#include <linux/sched.h>
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#include <linux/string.h>
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#include <linux/bootmem.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/kgdb.h>
#include <linux/topology.h>
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#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <asm/i387.h>
#include <asm/msr.h>
#include <asm/io.h>
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#include <asm/linkage.h>
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#include <asm/mmu_context.h>
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#include <asm/mtrr.h>
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#include <asm/mce.h>
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#include <asm/pat.h>
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#include <asm/asm.h>
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#include <asm/numa.h>
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#include <asm/smp.h>
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#include <asm/cpu.h>
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#include <asm/cpumask.h>
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#include <asm/apic.h>
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#ifdef CONFIG_X86_LOCAL_APIC
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#include <asm/uv/uv.h>
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#endif

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#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/desc.h>
#include <asm/atomic.h>
#include <asm/proto.h>
#include <asm/sections.h>
#include <asm/setup.h>
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#include <asm/hypervisor.h>
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#include <asm/stackprotector.h>
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#include "cpu.h"

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#ifdef CONFIG_X86_64

/* all of these masks are initialized in setup_cpu_local_masks() */
cpumask_var_t cpu_callin_mask;
cpumask_var_t cpu_callout_mask;
cpumask_var_t cpu_initialized_mask;

/* representing cpus for which sibling maps can be computed */
cpumask_var_t cpu_sibling_setup_mask;

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/* correctly size the local cpu masks */
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void __init setup_cpu_local_masks(void)
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{
	alloc_bootmem_cpumask_var(&cpu_initialized_mask);
	alloc_bootmem_cpumask_var(&cpu_callin_mask);
	alloc_bootmem_cpumask_var(&cpu_callout_mask);
	alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
}

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#else /* CONFIG_X86_32 */

cpumask_t cpu_callin_map;
cpumask_t cpu_callout_map;
cpumask_t cpu_initialized;
cpumask_t cpu_sibling_setup_map;

#endif /* CONFIG_X86_32 */


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static struct cpu_dev *this_cpu __cpuinitdata;

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DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
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#ifdef CONFIG_X86_64
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	/*
	 * We need valid kernel segments for data and code in long mode too
	 * IRET will check the segment types  kkeil 2000/10/28
	 * Also sysret mandates a special GDT layout
	 *
	 * The TLS descriptors are currently at a different place compared to i386.
	 * Hopefully nobody expects them at a fixed place (Wine?)
	 */
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	[GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
	[GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
#else
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	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00cf9a00 } } },
	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9200 } } },
	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00cffa00 } } },
	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff200 } } },
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	/*
	 * Segments used for calling PnP BIOS have byte granularity.
	 * They code segments and data segments have fixed 64k limits,
	 * the transfer segment sizes are set at run time.
	 */
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	/* 32-bit code */
	[GDT_ENTRY_PNPBIOS_CS32] = { { { 0x0000ffff, 0x00409a00 } } },
	/* 16-bit code */
	[GDT_ENTRY_PNPBIOS_CS16] = { { { 0x0000ffff, 0x00009a00 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_DS] = { { { 0x0000ffff, 0x00009200 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_TS1] = { { { 0x00000000, 0x00009200 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_TS2] = { { { 0x00000000, 0x00009200 } } },
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	/*
	 * The APM segments have byte granularity and their bases
	 * are set at run time.  All have 64k limits.
	 */
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	/* 32-bit code */
	[GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
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	/* 16-bit code */
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	[GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
	/* data */
	[GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
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	[GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
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	[GDT_ENTRY_PERCPU] = { { { 0x0000ffff, 0x00cf9200 } } },
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	GDT_STACK_CANARY_INIT
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#endif
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} };
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EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
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#ifdef CONFIG_X86_32
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static int cachesize_override __cpuinitdata = -1;
static int disable_x86_serial_nr __cpuinitdata = 1;
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static int __init cachesize_setup(char *str)
{
	get_option(&str, &cachesize_override);
	return 1;
}
__setup("cachesize=", cachesize_setup);

static int __init x86_fxsr_setup(char *s)
{
	setup_clear_cpu_cap(X86_FEATURE_FXSR);
	setup_clear_cpu_cap(X86_FEATURE_XMM);
	return 1;
}
__setup("nofxsr", x86_fxsr_setup);

static int __init x86_sep_setup(char *s)
{
	setup_clear_cpu_cap(X86_FEATURE_SEP);
	return 1;
}
__setup("nosep", x86_sep_setup);

/* Standard macro to see if a specific flag is changeable */
static inline int flag_is_changeable_p(u32 flag)
{
	u32 f1, f2;

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	/*
	 * Cyrix and IDT cpus allow disabling of CPUID
	 * so the code below may return different results
	 * when it is executed before and after enabling
	 * the CPUID. Add "volatile" to not allow gcc to
	 * optimize the subsequent calls to this function.
	 */
	asm volatile ("pushfl\n\t"
		      "pushfl\n\t"
		      "popl %0\n\t"
		      "movl %0,%1\n\t"
		      "xorl %2,%0\n\t"
		      "pushl %0\n\t"
		      "popfl\n\t"
		      "pushfl\n\t"
		      "popl %0\n\t"
		      "popfl\n\t"
		      : "=&r" (f1), "=&r" (f2)
		      : "ir" (flag));
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	return ((f1^f2) & flag) != 0;
}

/* Probe for the CPUID instruction */
static int __cpuinit have_cpuid_p(void)
{
	return flag_is_changeable_p(X86_EFLAGS_ID);
}

static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
	if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr) {
		/* Disable processor serial number */
		unsigned long lo, hi;
		rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
		lo |= 0x200000;
		wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
		printk(KERN_NOTICE "CPU serial number disabled.\n");
		clear_cpu_cap(c, X86_FEATURE_PN);

		/* Disabling the serial number may affect the cpuid level */
		c->cpuid_level = cpuid_eax(0);
	}
}

static int __init x86_serial_nr_setup(char *s)
{
	disable_x86_serial_nr = 0;
	return 1;
}
__setup("serialnumber", x86_serial_nr_setup);
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#else
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static inline int flag_is_changeable_p(u32 flag)
{
	return 1;
}
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/* Probe for the CPUID instruction */
static inline int have_cpuid_p(void)
{
	return 1;
}
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static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
}
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#endif
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/*
 * Some CPU features depend on higher CPUID levels, which may not always
 * be available due to CPUID level capping or broken virtualization
 * software.  Add those features to this table to auto-disable them.
 */
struct cpuid_dependent_feature {
	u32 feature;
	u32 level;
};
static const struct cpuid_dependent_feature __cpuinitconst
cpuid_dependent_features[] = {
	{ X86_FEATURE_MWAIT,		0x00000005 },
	{ X86_FEATURE_DCA,		0x00000009 },
	{ X86_FEATURE_XSAVE,		0x0000000d },
	{ 0, 0 }
};

static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
{
	const struct cpuid_dependent_feature *df;
	for (df = cpuid_dependent_features; df->feature; df++) {
		/*
		 * Note: cpuid_level is set to -1 if unavailable, but
		 * extended_extended_level is set to 0 if unavailable
		 * and the legitimate extended levels are all negative
		 * when signed; hence the weird messing around with
		 * signs here...
		 */
		if (cpu_has(c, df->feature) &&
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		    ((s32)df->level < 0 ?
		     (u32)df->level > (u32)c->extended_cpuid_level :
		     (s32)df->level > (s32)c->cpuid_level)) {
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			clear_cpu_cap(c, df->feature);
			if (warn)
				printk(KERN_WARNING
				       "CPU: CPU feature %s disabled "
				       "due to lack of CPUID level 0x%x\n",
				       x86_cap_flags[df->feature],
				       df->level);
		}
	}
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}
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/*
 * Naming convention should be: <Name> [(<Codename>)]
 * This table only is used unless init_<vendor>() below doesn't set it;
 * in particular, if CPUID levels 0x80000002..4 are supported, this isn't used
 *
 */

/* Look up CPU names by table lookup. */
static char __cpuinit *table_lookup_model(struct cpuinfo_x86 *c)
{
	struct cpu_model_info *info;

	if (c->x86_model >= 16)
		return NULL;	/* Range check */

	if (!this_cpu)
		return NULL;

	info = this_cpu->c_models;

	while (info && info->family) {
		if (info->family == c->x86)
			return info->model_names[c->x86_model];
		info++;
	}
	return NULL;		/* Not found */
}

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__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;

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void load_percpu_segment(int cpu)
{
#ifdef CONFIG_X86_32
	loadsegment(fs, __KERNEL_PERCPU);
#else
	loadsegment(gs, 0);
	wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
#endif
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	load_stack_canary_segment();
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}

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/* Current gdt points %fs at the "master" per-cpu area: after this,
 * it's on the real one. */
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void switch_to_new_gdt(int cpu)
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{
	struct desc_ptr gdt_descr;

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	gdt_descr.address = (long)get_cpu_gdt_table(cpu);
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	gdt_descr.size = GDT_SIZE - 1;
	load_gdt(&gdt_descr);
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	/* Reload the per-cpu base */
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	load_percpu_segment(cpu);
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}

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static struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
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static void __cpuinit default_init(struct cpuinfo_x86 *c)
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{
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#ifdef CONFIG_X86_64
	display_cacheinfo(c);
#else
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	/* Not much we can do here... */
	/* Check if at least it has cpuid */
	if (c->cpuid_level == -1) {
		/* No cpuid. It must be an ancient CPU */
		if (c->x86 == 4)
			strcpy(c->x86_model_id, "486");
		else if (c->x86 == 3)
			strcpy(c->x86_model_id, "386");
	}
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#endif
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}

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static struct cpu_dev __cpuinitdata default_cpu = {
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	.c_init	= default_init,
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	.c_vendor = "Unknown",
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	.c_x86_vendor = X86_VENDOR_UNKNOWN,
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};

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static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
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{
	unsigned int *v;
	char *p, *q;

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	if (c->extended_cpuid_level < 0x80000004)
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		return;
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	v = (unsigned int *) c->x86_model_id;
	cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
	cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
	cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
	c->x86_model_id[48] = 0;

	/* Intel chips right-justify this string for some dumb reason;
	   undo that brain damage */
	p = q = &c->x86_model_id[0];
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	while (*p == ' ')
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	     p++;
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	if (p != q) {
	     while (*p)
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		  *q++ = *p++;
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	     while (q <= &c->x86_model_id[48])
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		  *q++ = '\0';	/* Zero-pad the rest */
	}
}

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void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
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{
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	unsigned int n, dummy, ebx, ecx, edx, l2size;
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	n = c->extended_cpuid_level;
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	if (n >= 0x80000005) {
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		cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
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		printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
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				edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
		c->x86_cache_size = (ecx>>24) + (edx>>24);
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#ifdef CONFIG_X86_64
		/* On K8 L1 TLB is inclusive, so don't count it */
		c->x86_tlbsize = 0;
#endif
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	}

	if (n < 0x80000006)	/* Some chips just has a large L1. */
		return;

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	cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
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	l2size = ecx >> 16;
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#ifdef CONFIG_X86_64
	c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
#else
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	/* do processor-specific cache resizing */
	if (this_cpu->c_size_cache)
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		l2size = this_cpu->c_size_cache(c, l2size);
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	/* Allow user to override all this if necessary. */
	if (cachesize_override != -1)
		l2size = cachesize_override;

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	if (l2size == 0)
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		return;		/* Again, no L2 cache is possible */
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#endif
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	c->x86_cache_size = l2size;

	printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
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			l2size, ecx & 0xFF);
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}

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void __cpuinit detect_ht(struct cpuinfo_x86 *c)
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{
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#ifdef CONFIG_X86_HT
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	u32 eax, ebx, ecx, edx;
	int index_msb, core_bits;
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	if (!cpu_has(c, X86_FEATURE_HT))
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		return;
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	if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
		goto out;
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	if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
		return;
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	cpuid(1, &eax, &ebx, &ecx, &edx);
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	smp_num_siblings = (ebx & 0xff0000) >> 16;

	if (smp_num_siblings == 1) {
		printk(KERN_INFO  "CPU: Hyper-Threading is disabled\n");
	} else if (smp_num_siblings > 1) {

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		if (smp_num_siblings > nr_cpu_ids) {
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			printk(KERN_WARNING "CPU: Unsupported number of siblings %d",
					smp_num_siblings);
			smp_num_siblings = 1;
			return;
		}

		index_msb = get_count_order(smp_num_siblings);
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		c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
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		smp_num_siblings = smp_num_siblings / c->x86_max_cores;

		index_msb = get_count_order(smp_num_siblings);

		core_bits = get_count_order(c->x86_max_cores);

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		c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
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					       ((1 << core_bits) - 1);
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	}

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out:
	if ((c->x86_max_cores * smp_num_siblings) > 1) {
		printk(KERN_INFO  "CPU: Physical Processor ID: %d\n",
		       c->phys_proc_id);
		printk(KERN_INFO  "CPU: Processor Core ID: %d\n",
		       c->cpu_core_id);
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	}
#endif
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}
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static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
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{
	char *v = c->x86_vendor_id;
	int i;
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	static int printed;
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	for (i = 0; i < X86_VENDOR_NUM; i++) {
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		if (!cpu_devs[i])
			break;

		if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
		    (cpu_devs[i]->c_ident[1] &&
		     !strcmp(v, cpu_devs[i]->c_ident[1]))) {
			this_cpu = cpu_devs[i];
			c->x86_vendor = this_cpu->c_x86_vendor;
			return;
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		}
	}
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	if (!printed) {
		printed++;
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		printk(KERN_ERR "CPU: vendor_id '%s' unknown, using generic init.\n", v);
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		printk(KERN_ERR "CPU: Your system may be unstable.\n");
	}
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	c->x86_vendor = X86_VENDOR_UNKNOWN;
	this_cpu = &default_cpu;
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}

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void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
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{
	/* Get vendor name */
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	cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
	      (unsigned int *)&c->x86_vendor_id[0],
	      (unsigned int *)&c->x86_vendor_id[8],
	      (unsigned int *)&c->x86_vendor_id[4]);
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	c->x86 = 4;
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	/* Intel-defined flags: level 0x00000001 */
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	if (c->cpuid_level >= 0x00000001) {
		u32 junk, tfms, cap0, misc;
		cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
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		c->x86 = (tfms >> 8) & 0xf;
		c->x86_model = (tfms >> 4) & 0xf;
		c->x86_mask = tfms & 0xf;
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		if (c->x86 == 0xf)
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			c->x86 += (tfms >> 20) & 0xff;
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		if (c->x86 >= 0x6)
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			c->x86_model += ((tfms >> 16) & 0xf) << 4;
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		if (cap0 & (1<<19)) {
			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
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			c->x86_cache_alignment = c->x86_clflush_size;
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		}
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	}
}
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static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
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{
	u32 tfms, xlvl;
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	u32 ebx;
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	/* Intel-defined flags: level 0x00000001 */
	if (c->cpuid_level >= 0x00000001) {
		u32 capability, excap;
		cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
		c->x86_capability[0] = capability;
		c->x86_capability[4] = excap;
	}
541

542 543 544 545 546 547 548
	/* AMD-defined flags: level 0x80000001 */
	xlvl = cpuid_eax(0x80000000);
	c->extended_cpuid_level = xlvl;
	if ((xlvl & 0xffff0000) == 0x80000000) {
		if (xlvl >= 0x80000001) {
			c->x86_capability[1] = cpuid_edx(0x80000001);
			c->x86_capability[6] = cpuid_ecx(0x80000001);
549 550 551
		}
	}

552 553 554 555 556 557
#ifdef CONFIG_X86_64
	if (c->extended_cpuid_level >= 0x80000008) {
		u32 eax = cpuid_eax(0x80000008);

		c->x86_virt_bits = (eax >> 8) & 0xff;
		c->x86_phys_bits = eax & 0xff;
558
	}
559
#endif
560 561 562

	if (c->extended_cpuid_level >= 0x80000007)
		c->x86_power = cpuid_edx(0x80000007);
563 564

}
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static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_32
	int i;

	/*
	 * First of all, decide if this is a 486 or higher
	 * It's a 486 if we can modify the AC flag
	 */
	if (flag_is_changeable_p(X86_EFLAGS_AC))
		c->x86 = 4;
	else
		c->x86 = 3;

	for (i = 0; i < X86_VENDOR_NUM; i++)
		if (cpu_devs[i] && cpu_devs[i]->c_identify) {
			c->x86_vendor_id[0] = 0;
			cpu_devs[i]->c_identify(c);
			if (c->x86_vendor_id[0]) {
				get_cpu_vendor(c);
				break;
			}
		}
#endif
}

592 593 594 595 596 597 598 599 600
/*
 * Do minimum CPU detection early.
 * Fields really needed: vendor, cpuid_level, family, model, mask,
 * cache alignment.
 * The others are not touched to avoid unwanted side effects.
 *
 * WARNING: this function is only called on the BP.  Don't add code here
 * that is supposed to run on all CPUs.
 */
601
static void __init early_identify_cpu(struct cpuinfo_x86 *c)
602
{
603 604 605
#ifdef CONFIG_X86_64
	c->x86_clflush_size = 64;
#else
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	c->x86_clflush_size = 32;
607
#endif
608
	c->x86_cache_alignment = c->x86_clflush_size;
609

610
	memset(&c->x86_capability, 0, sizeof c->x86_capability);
611
	c->extended_cpuid_level = 0;
612

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	if (!have_cpuid_p())
		identify_cpu_without_cpuid(c);

	/* cyrix could have cpuid enabled via c_identify()*/
617 618 619 620 621
	if (!have_cpuid_p())
		return;

	cpu_detect(c);

622
	get_cpu_vendor(c);
623

624
	get_cpu_cap(c);
625

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	if (this_cpu->c_early_init)
		this_cpu->c_early_init(c);
628

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#ifdef CONFIG_SMP
630
	c->cpu_index = boot_cpu_id;
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#endif
632
	filter_cpuid_features(c, false);
633 634
}

635 636
void __init early_cpu_init(void)
{
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	struct cpu_dev **cdev;
	int count = 0;

	printk("KERNEL supported cpus:\n");
	for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
		struct cpu_dev *cpudev = *cdev;
		unsigned int j;
644

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		if (count >= X86_VENDOR_NUM)
			break;
		cpu_devs[count] = cpudev;
		count++;

		for (j = 0; j < 2; j++) {
			if (!cpudev->c_ident[j])
				continue;
			printk("  %s %s\n", cpudev->c_vendor,
				cpudev->c_ident[j]);
		}
	}
657 658

	early_identify_cpu(&boot_cpu_data);
659
}
660

661 662
/*
 * The NOPL instruction is supposed to exist on all CPUs with
663
 * family >= 6; unfortunately, that's not true in practice because
664
 * of early VIA chips and (more importantly) broken virtualizers that
665 666 667
 * are not easy to detect.  In the latter case it doesn't even *fail*
 * reliably, so probing for it doesn't even work.  Disable it completely
 * unless we can find a reliable way to detect all the broken cases.
668 669 670 671
 */
static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
{
	clear_cpu_cap(c, X86_FEATURE_NOPL);
672 673
}

674
static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
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{
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	c->extended_cpuid_level = 0;
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678
	if (!have_cpuid_p())
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		identify_cpu_without_cpuid(c);
680

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	/* cyrix could have cpuid enabled via c_identify()*/
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	if (!have_cpuid_p())
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		return;
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685
	cpu_detect(c);
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687
	get_cpu_vendor(c);
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689
	get_cpu_cap(c);
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691 692
	if (c->cpuid_level >= 0x00000001) {
		c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
693 694
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_HT
695
		c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
696
# else
697
		c->apicid = c->initial_apicid;
698 699
# endif
#endif
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701 702
#ifdef CONFIG_X86_HT
		c->phys_proc_id = c->initial_apicid;
703
#endif
704
	}
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706
	get_model_name(c); /* Default name */
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708 709
	init_scattered_cpuid_features(c);
	detect_nopl(c);
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}

/*
 * This does the hard work of actually picking apart the CPU stuff...
 */
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static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
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{
	int i;

	c->loops_per_jiffy = loops_per_jiffy;
	c->x86_cache_size = -1;
	c->x86_vendor = X86_VENDOR_UNKNOWN;
	c->x86_model = c->x86_mask = 0;	/* So far unknown... */
	c->x86_vendor_id[0] = '\0'; /* Unset */
	c->x86_model_id[0] = '\0';  /* Unset */
725
	c->x86_max_cores = 1;
726
	c->x86_coreid_bits = 0;
727
#ifdef CONFIG_X86_64
728 729 730
	c->x86_clflush_size = 64;
#else
	c->cpuid_level = -1;	/* CPUID not detected */
731
	c->x86_clflush_size = 32;
732 733
#endif
	c->x86_cache_alignment = c->x86_clflush_size;
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	memset(&c->x86_capability, 0, sizeof c->x86_capability);

	generic_identify(c);

738
	if (this_cpu->c_identify)
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		this_cpu->c_identify(c);

741
#ifdef CONFIG_X86_64
742
	c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
743 744
#endif

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	/*
	 * Vendor-specific initialization.  In this section we
	 * canonicalize the feature flags, meaning if there are
	 * features a certain CPU supports which CPUID doesn't
	 * tell us, CPUID claiming incorrect flags, or other bugs,
	 * we handle them here.
	 *
	 * At the end of this section, c->x86_capability better
	 * indicate the features this CPU genuinely supports!
	 */
	if (this_cpu->c_init)
		this_cpu->c_init(c);

	/* Disable the PN if appropriate */
	squash_the_stupid_serial_number(c);

	/*
	 * The vendor-specific functions might have changed features.  Now
	 * we do "generic changes."
	 */

766 767 768
	/* Filter out anything that depends on CPUID levels we don't have */
	filter_cpuid_features(c, true);

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	/* If the model name is still unset, do table lookup. */
770
	if (!c->x86_model_id[0]) {
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		char *p;
		p = table_lookup_model(c);
773
		if (p)
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			strcpy(c->x86_model_id, p);
		else
			/* Last resort... */
			sprintf(c->x86_model_id, "%02x/%02x",
778
				c->x86, c->x86_model);
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	}

781 782 783 784
#ifdef CONFIG_X86_64
	detect_ht(c);
#endif

785
	init_hypervisor(c);
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	/*
	 * On SMP, boot_cpu_data holds the common feature set between
	 * all CPUs; so make sure that we indicate which features are
	 * common between the CPUs.  The first time this routine gets
	 * executed, c == &boot_cpu_data.
	 */
792
	if (c != &boot_cpu_data) {
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		/* AND the already accumulated flags with these */
794
		for (i = 0; i < NCAPINTS; i++)
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			boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
	}

798 799
	/* Clear all flags overriden by options */
	for (i = 0; i < NCAPINTS; i++)
800
		c->x86_capability[i] &= ~cleared_cpu_caps[i];
801

802
#ifdef CONFIG_X86_MCE
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	/* Init Machine Check Exception if available. */
	mcheck_init(c);
805
#endif
806 807

	select_idle_routine(c);
808 809 810 811

#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
	numa_add_cpu(smp_processor_id());
#endif
812
}
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814 815 816 817 818 819 820 821 822 823
#ifdef CONFIG_X86_64
static void vgetcpu_set_mode(void)
{
	if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
		vgetcpu_mode = VGETCPU_RDTSCP;
	else
		vgetcpu_mode = VGETCPU_LSL;
}
#endif

824 825 826
void __init identify_boot_cpu(void)
{
	identify_cpu(&boot_cpu_data);
827
#ifdef CONFIG_X86_32
828
	sysenter_setup();
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	enable_sep_cpu();
830 831
#else
	vgetcpu_set_mode();
832
#endif
833
}
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835 836 837 838
void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
{
	BUG_ON(c == &boot_cpu_data);
	identify_cpu(c);
839
#ifdef CONFIG_X86_32
840
	enable_sep_cpu();
841
#endif
842
	mtrr_ap_init();
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}

845 846 847 848
struct msr_range {
	unsigned min;
	unsigned max;
};
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850 851 852 853 854 855
static struct msr_range msr_range_array[] __cpuinitdata = {
	{ 0x00000000, 0x00000418},
	{ 0xc0000000, 0xc000040b},
	{ 0xc0010000, 0xc0010142},
	{ 0xc0011000, 0xc001103b},
};
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857 858 859 860 861 862 863 864 865 866 867 868 869 870
static void __cpuinit print_cpu_msr(void)
{
	unsigned index;
	u64 val;
	int i;
	unsigned index_min, index_max;

	for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
		index_min = msr_range_array[i].min;
		index_max = msr_range_array[i].max;
		for (index = index_min; index < index_max; index++) {
			if (rdmsrl_amd_safe(index, &val))
				continue;
			printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
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		}
872 873
	}
}
874

875 876 877 878
static int show_msr __cpuinitdata;
static __init int setup_show_msr(char *arg)
{
	int num;
879

880
	get_option(&arg, &num);
881

882 883 884
	if (num > 0)
		show_msr = num;
	return 1;
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}
886
__setup("show_msr=", setup_show_msr);
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static __init int setup_noclflush(char *arg)
{
	setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
	return 1;
}
__setup("noclflush", setup_noclflush);

895
void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
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{
	char *vendor = NULL;

	if (c->x86_vendor < X86_VENDOR_NUM)
		vendor = this_cpu->c_vendor;
	else if (c->cpuid_level >= 0)
		vendor = c->x86_vendor_id;

904
	if (vendor && !strstr(c->x86_model_id, vendor))
905
		printk(KERN_CONT "%s ", vendor);
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907 908
	if (c->x86_model_id[0])
		printk(KERN_CONT "%s", c->x86_model_id);
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	else
910
		printk(KERN_CONT "%d86", c->x86);
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912
	if (c->x86_mask || c->cpuid_level >= 0)
913
		printk(KERN_CONT " stepping %02x\n", c->x86_mask);
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	else
915
		printk(KERN_CONT "\n");
916 917 918 919 920 921 922 923

#ifdef CONFIG_SMP
	if (c->cpu_index < show_msr)
		print_cpu_msr();
#else
	if (show_msr)
		print_cpu_msr();
#endif
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}

926 927 928 929 930 931 932 933 934 935 936
static __init int setup_disablecpuid(char *arg)
{
	int bit;
	if (get_option(&arg, &bit) && bit < NCAPINTS*32)
		setup_clear_cpu_cap(bit);
	else
		return 0;
	return 1;
}
__setup("clearcpuid=", setup_disablecpuid);

937 938 939
#ifdef CONFIG_X86_64
struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };

940 941
DEFINE_PER_CPU_FIRST(union irq_stack_union,
		     irq_stack_union) __aligned(PAGE_SIZE);
942
DEFINE_PER_CPU(char *, irq_stack_ptr) =
943
	init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
944

945 946 947
DEFINE_PER_CPU(unsigned long, kernel_stack) =
	(unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
EXPORT_PER_CPU_SYMBOL(kernel_stack);
948

949
DEFINE_PER_CPU(unsigned int, irq_count) = -1;
950

951 952 953
static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
	[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ])
	__aligned(PAGE_SIZE);
954 955 956 957 958

extern asmlinkage void ignore_sysret(void);

/* May not be marked __init: used by software suspend */
void syscall_init(void)
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{
960 961 962 963 964 965 966 967
	/*
	 * LSTAR and STAR live in a bit strange symbiosis.
	 * They both write to the same internal register. STAR allows to
	 * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
	 */
	wrmsrl(MSR_STAR,  ((u64)__USER32_CS)<<48  | ((u64)__KERNEL_CS)<<32);
	wrmsrl(MSR_LSTAR, system_call);
	wrmsrl(MSR_CSTAR, ignore_sysret);
968

969 970 971
#ifdef CONFIG_IA32_EMULATION
	syscall32_cpu_init();
#endif
972

973 974 975
	/* Flags to clear on syscall */
	wrmsrl(MSR_SYSCALL_MASK,
	       X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
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}
977

978 979 980 981 982 983 984 985
unsigned long kernel_eflags;

/*
 * Copies of the original ist values from the tss are only accessed during
 * debugging, no special alignment required.
 */
DEFINE_PER_CPU(struct orig_ist, orig_ist);

986
#else	/* x86_64 */
987

988 989 990
#ifdef CONFIG_CC_STACKPROTECTOR
DEFINE_PER_CPU(unsigned long, stack_canary);
#endif
991

992
/* Make sure %fs and %gs are initialized properly in idle threads */
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struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
994 995
{
	memset(regs, 0, sizeof(struct pt_regs));
996
	regs->fs = __KERNEL_PERCPU;
997
	regs->gs = __KERNEL_STACK_CANARY;
998 999
	return regs;
}
1000
#endif	/* x86_64 */
1001

1002 1003 1004 1005 1006
/*
 * cpu_init() initializes state that is per-CPU. Some data is already
 * initialized (naturally) in the bootstrap process, such as the GDT
 * and IDT. We reload them nevertheless, this function acts as a
 * 'CPU state barrier', nothing should get across.
1007
 * A lot of state is already set up in PDA init for 64 bit
1008
 */
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
#ifdef CONFIG_X86_64
void __cpuinit cpu_init(void)
{
	int cpu = stack_smp_processor_id();
	struct tss_struct *t = &per_cpu(init_tss, cpu);
	struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
	unsigned long v;
	struct task_struct *me;
	int i;

1019 1020 1021 1022 1023
#ifdef CONFIG_NUMA
	if (cpu != 0 && percpu_read(node_number) == 0 &&
	    cpu_to_node(cpu) != NUMA_NO_NODE)
		percpu_write(node_number, cpu_to_node(cpu));
#endif
1024 1025 1026

	me = current;

1027
	if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
		panic("CPU#%d already initialized!\n", cpu);

	printk(KERN_INFO "Initializing CPU#%d\n", cpu);

	clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);

	/*
	 * Initialize the per-CPU GDT with the boot GDT,
	 * and set up the GDT descriptor:
	 */

1039
	switch_to_new_gdt(cpu);
1040 1041
	loadsegment(fs, 0);

1042 1043 1044 1045 1046 1047 1048 1049 1050 1051
	load_idt((const struct desc_ptr *)&idt_descr);

	memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
	syscall_init();

	wrmsrl(MSR_FS_BASE, 0);
	wrmsrl(MSR_KERNEL_GS_BASE, 0);
	barrier();

	check_efer();
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	if (cpu != 0)
1053 1054 1055 1056 1057 1058
		enable_x2apic();

	/*
	 * set up and load the per-CPU TSS
	 */
	if (!orig_ist->ist[0]) {
1059 1060 1061
		static const unsigned int sizes[N_EXCEPTION_STACKS] = {
		  [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
		  [DEBUG_STACK - 1] = DEBUG_STKSZ
1062
		};
1063
		char *estacks = per_cpu(exception_stacks, cpu);
1064
		for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1065
			estacks += sizes[v];
1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098
			orig_ist->ist[v] = t->x86_tss.ist[v] =
					(unsigned long)estacks;
		}
	}

	t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
	/*
	 * <= is required because the CPU will access up to
	 * 8 bits beyond the end of the IO permission bitmap.
	 */
	for (i = 0; i <= IO_BITMAP_LONGS; i++)
		t->io_bitmap[i] = ~0UL;

	atomic_inc(&init_mm.mm_count);
	me->active_mm = &init_mm;
	if (me->mm)
		BUG();
	enter_lazy_tlb(&init_mm, me);

	load_sp0(t, &current->thread);
	set_tss_desc(cpu, t);
	load_TR_desc();
	load_LDT(&init_mm.context);

#ifdef CONFIG_KGDB
	/*
	 * If the kgdb is connected no debug regs should be altered.  This
	 * is only applicable when KGDB and a KGDB I/O module are built
	 * into the kernel and you are using early debugging with
	 * kgdbwait. KGDB will control the kernel HW breakpoint registers.
	 */
	if (kgdb_connected && arch_kgdb_ops.correct_hw_break)
		arch_kgdb_ops.correct_hw_break();
1099
	else
1100
#endif
1101 1102 1103 1104 1105 1106 1107 1108 1109 1110
	{
		/*
		 * Clear all 6 debug registers:
		 */
		set_debugreg(0UL, 0);
		set_debugreg(0UL, 1);
		set_debugreg(0UL, 2);
		set_debugreg(0UL, 3);
		set_debugreg(0UL, 6);
		set_debugreg(0UL, 7);
1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122
	}

	fpu_init();

	raw_local_save_flags(kernel_eflags);

	if (is_uv_system())
		uv_cpu_init();
}

#else

1123
void __cpuinit cpu_init(void)
1124
{
1125 1126
	int cpu = smp_processor_id();
	struct task_struct *curr = current;
1127
	struct tss_struct *t = &per_cpu(init_tss, cpu);
1128
	struct thread_struct *thread = &curr->thread;
1129

1130
	if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
1131 1132 1133 1134 1135 1136 1137 1138 1139
		printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
		for (;;) local_irq_enable();
	}

	printk(KERN_INFO "Initializing CPU#%d\n", cpu);

	if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
		clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);

1140
	load_idt(&idt_descr);
1141
	switch_to_new_gdt(cpu);
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	/*
	 * Set up and load the per-CPU TSS and LDT
	 */
	atomic_inc(&init_mm.mm_count);
1147 1148 1149 1150
	curr->active_mm = &init_mm;
	if (curr->mm)
		BUG();
	enter_lazy_tlb(&init_mm, curr);
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1151

1152
	load_sp0(t, thread);
1153
	set_tss_desc(cpu, t);
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	load_TR_desc();
	load_LDT(&init_mm.context);

1157
#ifdef CONFIG_DOUBLEFAULT
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1158 1159
	/* Set up doublefault TSS pointer in the GDT */
	__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1160
#endif
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	/* Clear all 6 debug registers: */
1163 1164 1165 1166 1167 1168
	set_debugreg(0, 0);
	set_debugreg(0, 1);
	set_debugreg(0, 2);
	set_debugreg(0, 3);
	set_debugreg(0, 6);
	set_debugreg(0, 7);
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	/*
	 * Force FPU initialization:
	 */
1173 1174 1175 1176
	if (cpu_has_xsave)
		current_thread_info()->status = TS_XSAVE;
	else
		current_thread_info()->status = 0;
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	clear_used_math();
	mxcsr_feature_mask_init();
1179 1180 1181 1182

	/*
	 * Boot processor to setup the FP and extended state context info.
	 */
1183
	if (smp_processor_id() == boot_cpu_id)
1184 1185 1186
		init_thread_xstate();

	xsave_init();
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}
1188

1189 1190

#endif