OpenCloudOS-Kernel/arch/x86/kernel/cpu/common.c

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#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/bootmem.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/kgdb.h>
#include <linux/topology.h>
#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <asm/i387.h>
#include <asm/msr.h>
#include <asm/io.h>
#include <asm/linkage.h>
#include <asm/mmu_context.h>
#include <asm/mtrr.h>
#include <asm/mce.h>
#include <asm/pat.h>
#include <asm/asm.h>
#include <asm/numa.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/mpspec.h>
#include <asm/apic.h>
#include <mach_apic.h>
#include <asm/genapic.h>
#endif
#include <asm/pda.h>
#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>
#include "cpu.h"
static struct cpu_dev *this_cpu __cpuinitdata;
#ifdef CONFIG_X86_64
/* 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?) */
DEFINE_PER_CPU(struct gdt_page, gdt_page) = { .gdt = {
[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
DEFINE_PER_CPU_PAGE_ALIGNED(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.
*/
/* 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 } } },
/*
* The APM segments have byte granularity and their bases
* are set at run time. All have 64k limits.
*/
/* 32-bit code */
[GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
/* 16-bit code */
[GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
/* data */
[GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
[GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
[GDT_ENTRY_PERCPU] = { { { 0x00000000, 0x00000000 } } },
} };
#endif
EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
#ifdef CONFIG_X86_32
static int cachesize_override __cpuinitdata = -1;
static int disable_x86_serial_nr __cpuinitdata = 1;
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;
/*
* 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));
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);
#else
static inline int flag_is_changeable_p(u32 flag)
{
return 1;
}
/* Probe for the CPUID instruction */
static inline int have_cpuid_p(void)
{
return 1;
}
static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
}
#endif
/*
* 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 */
}
__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;
/* 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 desc_ptr gdt_descr;
gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
#ifdef CONFIG_X86_32
asm("mov %0, %%fs" : : "r" (__KERNEL_PERCPU) : "memory");
#endif
}
static struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
static void __cpuinit default_init(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_64
display_cacheinfo(c);
#else
/* 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");
}
#endif
}
static struct cpu_dev __cpuinitdata default_cpu = {
.c_init = default_init,
.c_vendor = "Unknown",
.c_x86_vendor = X86_VENDOR_UNKNOWN,
};
static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
{
unsigned int *v;
char *p, *q;
if (c->extended_cpuid_level < 0x80000004)
return;
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 */
}
}
void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
{
unsigned int n, dummy, ebx, ecx, edx, l2size;
n = c->extended_cpuid_level;
if (n >= 0x80000005) {
cpuid(0x80000005, &dummy, &ebx, &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);
#ifdef CONFIG_X86_64
/* On K8 L1 TLB is inclusive, so don't count it */
c->x86_tlbsize = 0;
#endif
}
if (n < 0x80000006) /* Some chips just has a large L1. */
return;
cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
l2size = ecx >> 16;
#ifdef CONFIG_X86_64
c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
#else
/* 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 */
#endif
c->x86_cache_size = l2size;
printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
l2size, ecx & 0xFF);
}
void __cpuinit detect_ht(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_HT
u32 eax, ebx, ecx, edx;
int index_msb, core_bits;
if (!cpu_has(c, X86_FEATURE_HT))
return;
if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
goto out;
if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
return;
cpuid(1, &eax, &ebx, &ecx, &edx);
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 siblings %d",
smp_num_siblings);
smp_num_siblings = 1;
return;
}
index_msb = get_count_order(smp_num_siblings);
#ifdef CONFIG_X86_64
c->phys_proc_id = phys_pkg_id(index_msb);
#else
c->phys_proc_id = phys_pkg_id(c->initial_apicid, index_msb);
#endif
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);
#ifdef CONFIG_X86_64
c->cpu_core_id = phys_pkg_id(index_msb) &
((1 << core_bits) - 1);
#else
c->cpu_core_id = phys_pkg_id(c->initial_apicid, index_msb) &
((1 << core_bits) - 1);
#endif
}
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);
}
#endif
}
static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
{
char *v = c->x86_vendor_id;
int i;
static int printed;
for (i = 0; i < X86_VENDOR_NUM; i++) {
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;
}
}
if (!printed) {
printed++;
printk(KERN_ERR "CPU: vendor_id '%s' unknown, using generic init.\n", v);
printk(KERN_ERR "CPU: Your system may be unstable.\n");
}
c->x86_vendor = X86_VENDOR_UNKNOWN;
this_cpu = &default_cpu;
}
void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
{
/* Get vendor name */
x86: fix sparse warnings in cpu/common.c The casts will always be needed, may as well make them the right signedness. The ebx variables can easily be unsigned, may as well. arch/x86/kernel/cpu/common.c:261:21: warning: incorrect type in argument 2 (different signedness) arch/x86/kernel/cpu/common.c:261:21: expected unsigned int *eax arch/x86/kernel/cpu/common.c:261:21: got int *<noident> arch/x86/kernel/cpu/common.c:262:9: warning: incorrect type in argument 3 (different signedness) arch/x86/kernel/cpu/common.c:262:9: expected unsigned int *ebx arch/x86/kernel/cpu/common.c:262:9: got int *<noident> arch/x86/kernel/cpu/common.c:263:9: warning: incorrect type in argument 4 (different signedness) arch/x86/kernel/cpu/common.c:263:9: expected unsigned int *ecx arch/x86/kernel/cpu/common.c:263:9: got int *<noident> arch/x86/kernel/cpu/common.c:264:9: warning: incorrect type in argument 5 (different signedness) arch/x86/kernel/cpu/common.c:264:9: expected unsigned int *edx arch/x86/kernel/cpu/common.c:264:9: got int *<noident> arch/x86/kernel/cpu/common.c:293:30: warning: incorrect type in argument 3 (different signedness) arch/x86/kernel/cpu/common.c:293:30: expected unsigned int *ebx arch/x86/kernel/cpu/common.c:293:30: got int *<noident> arch/x86/kernel/cpu/common.c:350:22: warning: incorrect type in argument 2 (different signedness) arch/x86/kernel/cpu/common.c:350:22: expected unsigned int *eax arch/x86/kernel/cpu/common.c:350:22: got int *<noident> arch/x86/kernel/cpu/common.c:351:10: warning: incorrect type in argument 3 (different signedness) arch/x86/kernel/cpu/common.c:351:10: expected unsigned int *ebx arch/x86/kernel/cpu/common.c:351:10: got int *<noident> arch/x86/kernel/cpu/common.c:352:10: warning: incorrect type in argument 4 (different signedness) arch/x86/kernel/cpu/common.c:352:10: expected unsigned int *ecx arch/x86/kernel/cpu/common.c:352:10: got int *<noident> arch/x86/kernel/cpu/common.c:353:10: warning: incorrect type in argument 5 (different signedness) arch/x86/kernel/cpu/common.c:353:10: expected unsigned int *edx arch/x86/kernel/cpu/common.c:353:10: got int *<noident> arch/x86/kernel/cpu/common.c:362:30: warning: incorrect type in argument 3 (different signedness) arch/x86/kernel/cpu/common.c:362:30: expected unsigned int *ebx arch/x86/kernel/cpu/common.c:362:30: got int *<noident> Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-02 00:49:43 +08:00
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]);
c->x86 = 4;
/* Intel-defined flags: level 0x00000001 */
if (c->cpuid_level >= 0x00000001) {
u32 junk, tfms, cap0, misc;
cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
c->x86 = (tfms >> 8) & 0xf;
c->x86_model = (tfms >> 4) & 0xf;
c->x86_mask = tfms & 0xf;
if (c->x86 == 0xf)
c->x86 += (tfms >> 20) & 0xff;
if (c->x86 >= 0x6)
c->x86_model += ((tfms >> 16) & 0xf) << 4;
if (cap0 & (1<<19)) {
c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
c->x86_cache_alignment = c->x86_clflush_size;
}
}
}
static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
{
u32 tfms, xlvl;
u32 ebx;
/* 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;
}
/* 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);
}
}
#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;
}
#endif
if (c->extended_cpuid_level >= 0x80000007)
c->x86_power = cpuid_edx(0x80000007);
}
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
}
/*
* 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_identify_cpu(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_64
c->x86_clflush_size = 64;
#else
c->x86_clflush_size = 32;
#endif
c->x86_cache_alignment = c->x86_clflush_size;
memset(&c->x86_capability, 0, sizeof c->x86_capability);
c->extended_cpuid_level = 0;
if (!have_cpuid_p())
identify_cpu_without_cpuid(c);
/* cyrix could have cpuid enabled via c_identify()*/
if (!have_cpuid_p())
return;
cpu_detect(c);
get_cpu_vendor(c);
get_cpu_cap(c);
if (this_cpu->c_early_init)
this_cpu->c_early_init(c);
validate_pat_support(c);
#ifdef CONFIG_SMP
c->cpu_index = boot_cpu_id;
#endif
}
void __init early_cpu_init(void)
{
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;
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]);
}
}
early_identify_cpu(&boot_cpu_data);
}
/*
* The NOPL instruction is supposed to exist on all CPUs with
* family >= 6; unfortunately, that's not true in practice because
* of early VIA chips and (more importantly) broken virtualizers that
* 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.
*/
static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
{
clear_cpu_cap(c, X86_FEATURE_NOPL);
}
static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
{
c->extended_cpuid_level = 0;
if (!have_cpuid_p())
identify_cpu_without_cpuid(c);
/* cyrix could have cpuid enabled via c_identify()*/
if (!have_cpuid_p())
return;
cpu_detect(c);
get_cpu_vendor(c);
get_cpu_cap(c);
if (c->cpuid_level >= 0x00000001) {
c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_HT
c->apicid = phys_pkg_id(c->initial_apicid, 0);
# else
c->apicid = c->initial_apicid;
# endif
#endif
#ifdef CONFIG_X86_HT
c->phys_proc_id = c->initial_apicid;
#endif
}
get_model_name(c); /* Default name */
init_scattered_cpuid_features(c);
detect_nopl(c);
}
/*
* 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->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_coreid_bits = 0;
#ifdef CONFIG_X86_64
c->x86_clflush_size = 64;
#else
c->cpuid_level = -1; /* CPUID not detected */
c->x86_clflush_size = 32;
#endif
c->x86_cache_alignment = c->x86_clflush_size;
memset(&c->x86_capability, 0, sizeof c->x86_capability);
generic_identify(c);
if (this_cpu->c_identify)
this_cpu->c_identify(c);
#ifdef CONFIG_X86_64
c->apicid = phys_pkg_id(0);
#endif
/*
* 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."
*/
/* 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);
}
#ifdef CONFIG_X86_64
detect_ht(c);
#endif
/*
* 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];
}
/* Clear all flags overriden by options */
for (i = 0; i < NCAPINTS; i++)
x86: fix boot failure on 486 due to TSC breakage > Diffing dmesg between git7 and git8 doesn't sched any light since > git8 also removed the printouts of the x86 caps as they were being > initialised and updated. I'm currently adding those printouts back > in the hope of seeing where and when the caps get broken. That turned out to be very illuminating: --- dmesg-2.6.24-git7 2008-02-24 18:01:25.295851000 +0100 +++ dmesg-2.6.24-git8 2008-02-24 18:01:25.530358000 +0100 ... CPU: After generic identify, caps: 00000003 00000000 00000000 00000000 00000000 00000000 00000000 00000000 CPU: After all inits, caps: 00000003 00000000 00000000 00000000 00000000 00000000 00000000 00000000 +CPU: After applying cleared_cpu_caps, caps: 00000013 00000000 00000000 00000000 00000000 00000000 00000000 00000000 Notice how the TSC cap bit goes from Off to On. (The first two lines are printout loops from -git7 forward-ported to -git8, the third line is the same printout loop added just after the xor-with-cleared_cpu_caps[] loop.) Here's how the breakage occurs: 1. arch/x86/kernel/tsc_32.c:tsc_init() sees !cpu_has_tsc, so bails and calls setup_clear_cpu_cap(X86_FEATURE_TSC). 2. include/asm-x86/cpufeature.h:setup_clear_cpu_cap(bit) clears the bit in boot_cpu_data and sets it in cleared_cpu_caps 3. arch/x86/kernel/cpu/common.c:identify_cpu() XORs all caps in with cleared_cpu_caps HOWEVER, at this point c->x86_capability correctly has TSC Off, cleared_cpu_caps has TSC On, so the XOR incorrectly sets TSC to On in c->x86_capability, with disastrous results. The real bug is that clearing bits with XOR only works if the bits are known to be 1 prior to the XOR, and that's not true here. A simple fix is to convert the XOR to AND-NOT instead. The following patch does that, and allows my 486 to boot 2.6.25-rc kernels again. [ mingo@elte.hu: fixed a similar bug in setup_64.c as well. ] The breakage was introduced via commit 7d851c8d3db0. Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-25 01:27:03 +08:00
c->x86_capability[i] &= ~cleared_cpu_caps[i];
#ifdef CONFIG_X86_MCE
/* Init Machine Check Exception if available. */
mcheck_init(c);
#endif
select_idle_routine(c);
#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
numa_add_cpu(smp_processor_id());
#endif
}
#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
void __init identify_boot_cpu(void)
{
identify_cpu(&boot_cpu_data);
#ifdef CONFIG_X86_32
sysenter_setup();
enable_sep_cpu();
#else
vgetcpu_set_mode();
#endif
}
void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
{
BUG_ON(c == &boot_cpu_data);
identify_cpu(c);
#ifdef CONFIG_X86_32
enable_sep_cpu();
#endif
mtrr_ap_init();
}
struct msr_range {
unsigned min;
unsigned max;
};
static struct msr_range msr_range_array[] __cpuinitdata = {
{ 0x00000000, 0x00000418},
{ 0xc0000000, 0xc000040b},
{ 0xc0010000, 0xc0010142},
{ 0xc0011000, 0xc001103b},
};
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);
}
}
}
static int show_msr __cpuinitdata;
static __init int setup_show_msr(char *arg)
{
int num;
get_option(&arg, &num);
if (num > 0)
show_msr = num;
return 1;
}
__setup("show_msr=", setup_show_msr);
static __init int setup_noclflush(char *arg)
{
setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
return 1;
}
__setup("noclflush", setup_noclflush);
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 && !strstr(c->x86_model_id, vendor))
printk(KERN_CONT "%s ", vendor);
if (c->x86_model_id[0])
printk(KERN_CONT "%s", c->x86_model_id);
else
printk(KERN_CONT "%d86", c->x86);
if (c->x86_mask || c->cpuid_level >= 0)
printk(KERN_CONT " stepping %02x\n", c->x86_mask);
else
printk(KERN_CONT "\n");
#ifdef CONFIG_SMP
if (c->cpu_index < show_msr)
print_cpu_msr();
#else
if (show_msr)
print_cpu_msr();
#endif
}
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);
cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;
#ifdef CONFIG_X86_64
struct x8664_pda **_cpu_pda __read_mostly;
EXPORT_SYMBOL(_cpu_pda);
struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };
char boot_cpu_stack[IRQSTACKSIZE] __page_aligned_bss;
void __cpuinit pda_init(int cpu)
{
struct x8664_pda *pda = cpu_pda(cpu);
/* Setup up data that may be needed in __get_free_pages early */
loadsegment(fs, 0);
loadsegment(gs, 0);
/* Memory clobbers used to order PDA accessed */
mb();
wrmsrl(MSR_GS_BASE, pda);
mb();
pda->cpunumber = cpu;
pda->irqcount = -1;
pda->kernelstack = (unsigned long)stack_thread_info() -
PDA_STACKOFFSET + THREAD_SIZE;
pda->active_mm = &init_mm;
pda->mmu_state = 0;
if (cpu == 0) {
/* others are initialized in smpboot.c */
pda->pcurrent = &init_task;
pda->irqstackptr = boot_cpu_stack;
pda->irqstackptr += IRQSTACKSIZE - 64;
} else {
if (!pda->irqstackptr) {
pda->irqstackptr = (char *)
__get_free_pages(GFP_ATOMIC, IRQSTACK_ORDER);
if (!pda->irqstackptr)
panic("cannot allocate irqstack for cpu %d",
cpu);
pda->irqstackptr += IRQSTACKSIZE - 64;
}
if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE)
pda->nodenumber = cpu_to_node(cpu);
}
}
char boot_exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ +
DEBUG_STKSZ] __page_aligned_bss;
extern asmlinkage void ignore_sysret(void);
/* May not be marked __init: used by software suspend */
void syscall_init(void)
{
/*
* 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);
#ifdef CONFIG_IA32_EMULATION
syscall32_cpu_init();
#endif
/* Flags to clear on syscall */
wrmsrl(MSR_SYSCALL_MASK,
X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
}
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);
#else
/* Make sure %fs is initialized properly in idle threads */
struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
{
memset(regs, 0, sizeof(struct pt_regs));
regs->fs = __KERNEL_PERCPU;
return regs;
}
#endif
/*
* 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.
* A lot of state is already set up in PDA init for 64 bit
*/
#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;
char *estacks = NULL;
struct task_struct *me;
int i;
/* CPU 0 is initialised in head64.c */
if (cpu != 0)
pda_init(cpu);
else
estacks = boot_exception_stacks;
me = current;
if (cpu_test_and_set(cpu, cpu_initialized))
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:
*/
switch_to_new_gdt();
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();
if (cpu != 0 && x2apic)
enable_x2apic();
/*
* set up and load the per-CPU TSS
*/
if (!orig_ist->ist[0]) {
static const unsigned int order[N_EXCEPTION_STACKS] = {
[0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STACK_ORDER,
[DEBUG_STACK - 1] = DEBUG_STACK_ORDER
};
for (v = 0; v < N_EXCEPTION_STACKS; v++) {
if (cpu) {
estacks = (char *)__get_free_pages(GFP_ATOMIC, order[v]);
if (!estacks)
panic("Cannot allocate exception "
"stack %ld %d\n", v, cpu);
}
estacks += PAGE_SIZE << order[v];
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();
else {
#endif
/*
* 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);
#ifdef CONFIG_KGDB
/* If the kgdb is connected no debug regs should be altered. */
}
#endif
fpu_init();
raw_local_save_flags(kernel_eflags);
if (is_uv_system())
uv_cpu_init();
}
#else
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);
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_sp0(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:
*/
if (cpu_has_xsave)
current_thread_info()->status = TS_XSAVE;
else
current_thread_info()->status = 0;
clear_used_math();
mxcsr_feature_mask_init();
/*
* Boot processor to setup the FP and extended state context info.
*/
if (smp_processor_id() == boot_cpu_id)
init_thread_xstate();
xsave_init();
}
#endif