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author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:16:58 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:16:58 +0200 |
commit | f7627e2513987bb5d4e8cb13c4e0a478352141ac (patch) | |
tree | 46ef70a107285c1dfe8161a57f433d30252d285a /arch/x86/kernel/cpu/common.c | |
parent | 4ac24f63fd203bc12a841a88a2034dccd358d0d1 (diff) | |
download | linux-f7627e2513987bb5d4e8cb13c4e0a478352141ac.tar.gz linux-f7627e2513987bb5d4e8cb13c4e0a478352141ac.tar.bz2 linux-f7627e2513987bb5d4e8cb13c4e0a478352141ac.zip |
i386: move kernel/cpu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r-- | arch/x86/kernel/cpu/common.c | 733 |
1 files changed, 733 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c new file mode 100644 index 000000000000..d506201d397c --- /dev/null +++ b/arch/x86/kernel/cpu/common.c @@ -0,0 +1,733 @@ +#include <linux/init.h> +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/smp.h> +#include <linux/module.h> +#include <linux/percpu.h> +#include <linux/bootmem.h> +#include <asm/semaphore.h> +#include <asm/processor.h> +#include <asm/i387.h> +#include <asm/msr.h> +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/mtrr.h> +#include <asm/mce.h> +#ifdef CONFIG_X86_LOCAL_APIC +#include <asm/mpspec.h> +#include <asm/apic.h> +#include <mach_apic.h> +#endif + +#include "cpu.h" + +DEFINE_PER_CPU(struct gdt_page, gdt_page) = { .gdt = { + [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 }, + /* + * 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. + */ + [GDT_ENTRY_PNPBIOS_CS32] = { 0x0000ffff, 0x00409a00 },/* 32-bit code */ + [GDT_ENTRY_PNPBIOS_CS16] = { 0x0000ffff, 0x00009a00 },/* 16-bit code */ + [GDT_ENTRY_PNPBIOS_DS] = { 0x0000ffff, 0x00009200 }, /* 16-bit data */ + [GDT_ENTRY_PNPBIOS_TS1] = { 0x00000000, 0x00009200 },/* 16-bit data */ + [GDT_ENTRY_PNPBIOS_TS2] = { 0x00000000, 0x00009200 },/* 16-bit data */ + /* + * The APM segments have byte granularity and their bases + * are set at run time. All have 64k limits. + */ + [GDT_ENTRY_APMBIOS_BASE] = { 0x0000ffff, 0x00409a00 },/* 32-bit code */ + /* 16-bit code */ + [GDT_ENTRY_APMBIOS_BASE+1] = { 0x0000ffff, 0x00009a00 }, + [GDT_ENTRY_APMBIOS_BASE+2] = { 0x0000ffff, 0x00409200 }, /* data */ + + [GDT_ENTRY_ESPFIX_SS] = { 0x00000000, 0x00c09200 }, + [GDT_ENTRY_PERCPU] = { 0x00000000, 0x00000000 }, +} }; +EXPORT_PER_CPU_SYMBOL_GPL(gdt_page); + +static int cachesize_override __cpuinitdata = -1; +static int disable_x86_fxsr __cpuinitdata; +static int disable_x86_serial_nr __cpuinitdata = 1; +static int disable_x86_sep __cpuinitdata; + +struct cpu_dev * cpu_devs[X86_VENDOR_NUM] = {}; + +extern int disable_pse; + +static void __cpuinit default_init(struct cpuinfo_x86 * c) +{ + /* 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"); + } +} + +static struct cpu_dev __cpuinitdata default_cpu = { + .c_init = default_init, + .c_vendor = "Unknown", +}; +static struct cpu_dev * this_cpu __cpuinitdata = &default_cpu; + +static int __init cachesize_setup(char *str) +{ + get_option (&str, &cachesize_override); + return 1; +} +__setup("cachesize=", cachesize_setup); + +int __cpuinit get_model_name(struct cpuinfo_x86 *c) +{ + unsigned int *v; + char *p, *q; + + if (cpuid_eax(0x80000000) < 0x80000004) + return 0; + + 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]; + while ( *p == ' ' ) + p++; + if ( p != q ) { + while ( *p ) + *q++ = *p++; + while ( q <= &c->x86_model_id[48] ) + *q++ = '\0'; /* Zero-pad the rest */ + } + + return 1; +} + + +void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c) +{ + unsigned int n, dummy, ecx, edx, l2size; + + n = cpuid_eax(0x80000000); + + if (n >= 0x80000005) { + cpuid(0x80000005, &dummy, &dummy, &ecx, &edx); + printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n", + edx>>24, edx&0xFF, ecx>>24, ecx&0xFF); + c->x86_cache_size=(ecx>>24)+(edx>>24); + } + + if (n < 0x80000006) /* Some chips just has a large L1. */ + return; + + ecx = cpuid_ecx(0x80000006); + l2size = ecx >> 16; + + /* do processor-specific cache resizing */ + if (this_cpu->c_size_cache) + l2size = this_cpu->c_size_cache(c,l2size); + + /* Allow user to override all this if necessary. */ + if (cachesize_override != -1) + l2size = cachesize_override; + + if ( l2size == 0 ) + return; /* Again, no L2 cache is possible */ + + c->x86_cache_size = l2size; + + printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n", + l2size, ecx & 0xFF); +} + +/* 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 */ +} + + +static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c, int early) +{ + char *v = c->x86_vendor_id; + int i; + static int printed; + + for (i = 0; i < X86_VENDOR_NUM; i++) { + if (cpu_devs[i]) { + if (!strcmp(v,cpu_devs[i]->c_ident[0]) || + (cpu_devs[i]->c_ident[1] && + !strcmp(v,cpu_devs[i]->c_ident[1]))) { + c->x86_vendor = i; + if (!early) + this_cpu = cpu_devs[i]; + return; + } + } + } + if (!printed) { + printed++; + printk(KERN_ERR "CPU: Vendor unknown, using generic init.\n"); + printk(KERN_ERR "CPU: Your system may be unstable.\n"); + } + c->x86_vendor = X86_VENDOR_UNKNOWN; + this_cpu = &default_cpu; +} + + +static int __init x86_fxsr_setup(char * s) +{ + /* Tell all the other CPU's to not use it... */ + disable_x86_fxsr = 1; + + /* + * ... and clear the bits early in the boot_cpu_data + * so that the bootup process doesn't try to do this + * either. + */ + clear_bit(X86_FEATURE_FXSR, boot_cpu_data.x86_capability); + clear_bit(X86_FEATURE_XMM, boot_cpu_data.x86_capability); + return 1; +} +__setup("nofxsr", x86_fxsr_setup); + + +static int __init x86_sep_setup(char * s) +{ + disable_x86_sep = 1; + 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; + + asm("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)); + + 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); +} + +void __init cpu_detect(struct cpuinfo_x86 *c) +{ + /* Get vendor name */ + cpuid(0x00000000, &c->cpuid_level, + (int *)&c->x86_vendor_id[0], + (int *)&c->x86_vendor_id[8], + (int *)&c->x86_vendor_id[4]); + + c->x86 = 4; + if (c->cpuid_level >= 0x00000001) { + u32 junk, tfms, cap0, misc; + cpuid(0x00000001, &tfms, &misc, &junk, &cap0); + c->x86 = (tfms >> 8) & 15; + c->x86_model = (tfms >> 4) & 15; + if (c->x86 == 0xf) + c->x86 += (tfms >> 20) & 0xff; + if (c->x86 >= 0x6) + c->x86_model += ((tfms >> 16) & 0xF) << 4; + c->x86_mask = tfms & 15; + if (cap0 & (1<<19)) + c->x86_cache_alignment = ((misc >> 8) & 0xff) * 8; + } +} + +/* 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. */ +static void __init early_cpu_detect(void) +{ + struct cpuinfo_x86 *c = &boot_cpu_data; + + c->x86_cache_alignment = 32; + + if (!have_cpuid_p()) + return; + + cpu_detect(c); + + get_cpu_vendor(c, 1); +} + +static void __cpuinit generic_identify(struct cpuinfo_x86 * c) +{ + u32 tfms, xlvl; + int ebx; + + if (have_cpuid_p()) { + /* Get vendor name */ + cpuid(0x00000000, &c->cpuid_level, + (int *)&c->x86_vendor_id[0], + (int *)&c->x86_vendor_id[8], + (int *)&c->x86_vendor_id[4]); + + get_cpu_vendor(c, 0); + /* Initialize the standard set of capabilities */ + /* Note that the vendor-specific code below might override */ + + /* 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; + c->x86 = (tfms >> 8) & 15; + c->x86_model = (tfms >> 4) & 15; + if (c->x86 == 0xf) + c->x86 += (tfms >> 20) & 0xff; + if (c->x86 >= 0x6) + c->x86_model += ((tfms >> 16) & 0xF) << 4; + c->x86_mask = tfms & 15; +#ifdef CONFIG_X86_HT + c->apicid = phys_pkg_id((ebx >> 24) & 0xFF, 0); +#else + c->apicid = (ebx >> 24) & 0xFF; +#endif + if (c->x86_capability[0] & (1<<19)) + c->x86_clflush_size = ((ebx >> 8) & 0xff) * 8; + } else { + /* Have CPUID level 0 only - unheard of */ + c->x86 = 4; + } + + /* AMD-defined flags: level 0x80000001 */ + xlvl = cpuid_eax(0x80000000); + if ( (xlvl & 0xffff0000) == 0x80000000 ) { + if ( xlvl >= 0x80000001 ) { + c->x86_capability[1] = cpuid_edx(0x80000001); + c->x86_capability[6] = cpuid_ecx(0x80000001); + } + if ( xlvl >= 0x80000004 ) + get_model_name(c); /* Default name */ + } + + init_scattered_cpuid_features(c); + } + + early_intel_workaround(c); + +#ifdef CONFIG_X86_HT + c->phys_proc_id = (cpuid_ebx(1) >> 24) & 0xff; +#endif +} + +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_bit(X86_FEATURE_PN, c->x86_capability); + + /* 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); + + + +/* + * This does the hard work of actually picking apart the CPU stuff... + */ +static void __cpuinit identify_cpu(struct cpuinfo_x86 *c) +{ + int i; + + c->loops_per_jiffy = loops_per_jiffy; + c->x86_cache_size = -1; + c->x86_vendor = X86_VENDOR_UNKNOWN; + c->cpuid_level = -1; /* CPUID not detected */ + c->x86_model = c->x86_mask = 0; /* So far unknown... */ + c->x86_vendor_id[0] = '\0'; /* Unset */ + c->x86_model_id[0] = '\0'; /* Unset */ + c->x86_max_cores = 1; + c->x86_clflush_size = 32; + memset(&c->x86_capability, 0, sizeof c->x86_capability); + + if (!have_cpuid_p()) { + /* 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; + } + + generic_identify(c); + + printk(KERN_DEBUG "CPU: After generic identify, caps:"); + for (i = 0; i < NCAPINTS; i++) + printk(" %08lx", c->x86_capability[i]); + printk("\n"); + + if (this_cpu->c_identify) { + this_cpu->c_identify(c); + + printk(KERN_DEBUG "CPU: After vendor identify, caps:"); + for (i = 0; i < NCAPINTS; i++) + printk(" %08lx", c->x86_capability[i]); + printk("\n"); + } + + /* + * 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." + */ + + /* TSC disabled? */ + if ( tsc_disable ) + clear_bit(X86_FEATURE_TSC, c->x86_capability); + + /* FXSR disabled? */ + if (disable_x86_fxsr) { + clear_bit(X86_FEATURE_FXSR, c->x86_capability); + clear_bit(X86_FEATURE_XMM, c->x86_capability); + } + + /* SEP disabled? */ + if (disable_x86_sep) + clear_bit(X86_FEATURE_SEP, c->x86_capability); + + if (disable_pse) + clear_bit(X86_FEATURE_PSE, c->x86_capability); + + /* If the model name is still unset, do table lookup. */ + if ( !c->x86_model_id[0] ) { + char *p; + p = table_lookup_model(c); + if ( p ) + strcpy(c->x86_model_id, p); + else + /* Last resort... */ + sprintf(c->x86_model_id, "%02x/%02x", + c->x86, c->x86_model); + } + + /* Now the feature flags better reflect actual CPU features! */ + + printk(KERN_DEBUG "CPU: After all inits, caps:"); + for (i = 0; i < NCAPINTS; i++) + printk(" %08lx", c->x86_capability[i]); + printk("\n"); + + /* + * 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. + */ + if ( c != &boot_cpu_data ) { + /* AND the already accumulated flags with these */ + for ( i = 0 ; i < NCAPINTS ; i++ ) + boot_cpu_data.x86_capability[i] &= c->x86_capability[i]; + } + + /* Init Machine Check Exception if available. */ + mcheck_init(c); +} + +void __init identify_boot_cpu(void) +{ + identify_cpu(&boot_cpu_data); + sysenter_setup(); + enable_sep_cpu(); + mtrr_bp_init(); +} + +void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c) +{ + BUG_ON(c == &boot_cpu_data); + identify_cpu(c); + enable_sep_cpu(); + mtrr_ap_init(); +} + +#ifdef CONFIG_X86_HT +void __cpuinit detect_ht(struct cpuinfo_x86 *c) +{ + u32 eax, ebx, ecx, edx; + int index_msb, core_bits; + + cpuid(1, &eax, &ebx, &ecx, &edx); + + if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY)) + return; + + 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 ) { + + if (smp_num_siblings > NR_CPUS) { + printk(KERN_WARNING "CPU: Unsupported number of the " + "siblings %d", smp_num_siblings); + smp_num_siblings = 1; + return; + } + + index_msb = get_count_order(smp_num_siblings); + c->phys_proc_id = phys_pkg_id((ebx >> 24) & 0xFF, index_msb); + + printk(KERN_INFO "CPU: Physical Processor ID: %d\n", + c->phys_proc_id); + + 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); + + c->cpu_core_id = phys_pkg_id((ebx >> 24) & 0xFF, index_msb) & + ((1 << core_bits) - 1); + + if (c->x86_max_cores > 1) + printk(KERN_INFO "CPU: Processor Core ID: %d\n", + c->cpu_core_id); + } +} +#endif + +void __cpuinit print_cpu_info(struct cpuinfo_x86 *c) +{ + 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; + + if (vendor && strncmp(c->x86_model_id, vendor, strlen(vendor))) + printk("%s ", vendor); + + if (!c->x86_model_id[0]) + printk("%d86", c->x86); + else + printk("%s", c->x86_model_id); + + if (c->x86_mask || c->cpuid_level >= 0) + printk(" stepping %02x\n", c->x86_mask); + else + printk("\n"); +} + +cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE; + +/* This is hacky. :) + * We're emulating future behavior. + * In the future, the cpu-specific init functions will be called implicitly + * via the magic of initcalls. + * They will insert themselves into the cpu_devs structure. + * Then, when cpu_init() is called, we can just iterate over that array. + */ + +extern int intel_cpu_init(void); +extern int cyrix_init_cpu(void); +extern int nsc_init_cpu(void); +extern int amd_init_cpu(void); +extern int centaur_init_cpu(void); +extern int transmeta_init_cpu(void); +extern int nexgen_init_cpu(void); +extern int umc_init_cpu(void); + +void __init early_cpu_init(void) +{ + intel_cpu_init(); + cyrix_init_cpu(); + nsc_init_cpu(); + amd_init_cpu(); + centaur_init_cpu(); + transmeta_init_cpu(); + nexgen_init_cpu(); + umc_init_cpu(); + early_cpu_detect(); + +#ifdef CONFIG_DEBUG_PAGEALLOC + /* pse is not compatible with on-the-fly unmapping, + * disable it even if the cpus claim to support it. + */ + clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability); + disable_pse = 1; +#endif +} + +/* Make sure %fs is initialized properly in idle threads */ +struct pt_regs * __devinit idle_regs(struct pt_regs *regs) +{ + memset(regs, 0, sizeof(struct pt_regs)); + regs->xfs = __KERNEL_PERCPU; + return regs; +} + +/* Current gdt points %fs at the "master" per-cpu area: after this, + * it's on the real one. */ +void switch_to_new_gdt(void) +{ + struct Xgt_desc_struct gdt_descr; + + gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id()); + gdt_descr.size = GDT_SIZE - 1; + load_gdt(&gdt_descr); + asm("mov %0, %%fs" : : "r" (__KERNEL_PERCPU) : "memory"); +} + +/* + * 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. + */ +void __cpuinit cpu_init(void) +{ + int cpu = smp_processor_id(); + struct task_struct *curr = current; + struct tss_struct * t = &per_cpu(init_tss, cpu); + struct thread_struct *thread = &curr->thread; + + if (cpu_test_and_set(cpu, cpu_initialized)) { + 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); + if (tsc_disable && cpu_has_tsc) { + printk(KERN_NOTICE "Disabling TSC...\n"); + /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/ + clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability); + set_in_cr4(X86_CR4_TSD); + } + + load_idt(&idt_descr); + switch_to_new_gdt(); + + /* + * Set up and load the per-CPU TSS and LDT + */ + atomic_inc(&init_mm.mm_count); + curr->active_mm = &init_mm; + if (curr->mm) + BUG(); + enter_lazy_tlb(&init_mm, curr); + + load_esp0(t, thread); + set_tss_desc(cpu,t); + load_TR_desc(); + load_LDT(&init_mm.context); + +#ifdef CONFIG_DOUBLEFAULT + /* Set up doublefault TSS pointer in the GDT */ + __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss); +#endif + + /* Clear %gs. */ + asm volatile ("mov %0, %%gs" : : "r" (0)); + + /* Clear all 6 debug registers: */ + set_debugreg(0, 0); + set_debugreg(0, 1); + set_debugreg(0, 2); + set_debugreg(0, 3); + set_debugreg(0, 6); + set_debugreg(0, 7); + + /* + * Force FPU initialization: + */ + current_thread_info()->status = 0; + clear_used_math(); + mxcsr_feature_mask_init(); +} + +#ifdef CONFIG_HOTPLUG_CPU +void __cpuinit cpu_uninit(void) +{ + int cpu = raw_smp_processor_id(); + cpu_clear(cpu, cpu_initialized); + + /* lazy TLB state */ + per_cpu(cpu_tlbstate, cpu).state = 0; + per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm; +} +#endif |