android_kernel_xiaomi_sm8350/arch/i386/kernel/cpu/common.c
James Bottomley 2b932f6cf0 [PATCH] x86: fix broken SMP boot sequence
Recent GDT changes broke the SMP boot sequence if the booting CPU is
numbered anything other than zero.  There's also a subtle source of error
in that the boot time CPU now uses cpu_gdt_table (which is actually the GDT
for booting CPUs in head.S).  This patch fixes both problems by making GDT
descriptors themselves allocated from a per_cpu area and switching to them
in cpu_init(), which now means that cpu_gdt_table is exclusively used for
booting CPUs again.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Matt Tolentino <metolent@snoqualmie.dp.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:38 -08:00

683 lines
17 KiB
C

#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>
#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 Xgt_desc_struct, cpu_gdt_descr);
EXPORT_PER_CPU_SYMBOL(cpu_gdt_descr);
DEFINE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
static int cachesize_override __devinitdata = -1;
static int disable_x86_fxsr __devinitdata = 0;
static int disable_x86_serial_nr __devinitdata = 1;
struct cpu_dev * cpu_devs[X86_VENDOR_NUM] = {};
extern int disable_pse;
static void 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 default_cpu = {
.c_init = default_init,
.c_vendor = "Unknown",
};
static struct cpu_dev * this_cpu = &default_cpu;
static int __init cachesize_setup(char *str)
{
get_option (&str, &cachesize_override);
return 1;
}
__setup("cachesize=", cachesize_setup);
int __devinit 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 __devinit 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 __devinit *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 __devinit 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)
{
disable_x86_fxsr = 1;
return 1;
}
__setup("nofxsr", x86_fxsr_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 __devinit have_cpuid_p(void)
{
return flag_is_changeable_p(X86_EFLAGS_ID);
}
/* 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;
/* 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, 1);
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;
}
}
void __devinit generic_identify(struct cpuinfo_x86 * c)
{
u32 tfms, xlvl;
int junk;
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, &junk, &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;
c->x86_model += ((tfms >> 16) & 0xF) << 4;
}
c->x86_mask = tfms & 15;
} 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 */
}
}
early_intel_workaround(c);
#ifdef CONFIG_X86_HT
phys_proc_id[smp_processor_id()] = (cpuid_ebx(1) >> 24) & 0xff;
#endif
}
static void __devinit 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...
*/
void __devinit 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;
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);
}
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_vendor, 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);
if (c == &boot_cpu_data)
sysenter_setup();
enable_sep_cpu();
if (c == &boot_cpu_data)
mtrr_bp_init();
else
mtrr_ap_init();
}
#ifdef CONFIG_X86_HT
void __devinit detect_ht(struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;
int index_msb, core_bits;
int cpu = smp_processor_id();
cpuid(1, &eax, &ebx, &ecx, &edx);
c->apicid = phys_pkg_id((ebx >> 24) & 0xFF, 0);
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);
phys_proc_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
phys_proc_id[cpu]);
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);
cpu_core_id[cpu] = 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",
cpu_core_id[cpu]);
}
}
#endif
void __devinit 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 __devinitdata = 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 rise_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();
rise_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
}
/*
* 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 __devinit cpu_init(void)
{
int cpu = smp_processor_id();
struct tss_struct * t = &per_cpu(init_tss, cpu);
struct thread_struct *thread = &current->thread;
struct desc_struct *gdt;
__u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
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);
}
/*
* This is a horrible hack to allocate the GDT. The problem
* is that cpu_init() is called really early for the boot CPU
* (and hence needs bootmem) but much later for the secondary
* CPUs, when bootmem will have gone away
*/
if (NODE_DATA(0)->bdata->node_bootmem_map) {
gdt = (struct desc_struct *)alloc_bootmem_pages(PAGE_SIZE);
/* alloc_bootmem_pages panics on failure, so no check */
memset(gdt, 0, PAGE_SIZE);
} else {
gdt = (struct desc_struct *)get_zeroed_page(GFP_KERNEL);
if (unlikely(!gdt)) {
printk(KERN_CRIT "CPU%d failed to allocate GDT\n", cpu);
for (;;)
local_irq_enable();
}
}
/*
* Initialize the per-CPU GDT with the boot GDT,
* and set up the GDT descriptor:
*/
memcpy(gdt, cpu_gdt_table, GDT_SIZE);
/* Set up GDT entry for 16bit stack */
*(__u64 *)(&gdt[GDT_ENTRY_ESPFIX_SS]) |=
((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
(CPU_16BIT_STACK_SIZE - 1);
cpu_gdt_descr->size = GDT_SIZE - 1;
cpu_gdt_descr->address = (unsigned long)gdt;
load_gdt(cpu_gdt_descr);
load_idt(&idt_descr);
/*
* Set up and load the per-CPU TSS and LDT
*/
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
if (current->mm)
BUG();
enter_lazy_tlb(&init_mm, current);
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 %fs and %gs. */
asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
/* 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 __devinit 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