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Diffstat (limited to 'arch/i386/kernel/cpu/common.c')
-rw-r--r--arch/i386/kernel/cpu/common.c634
1 files changed, 634 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c
new file mode 100644
index 000000000000..ebd5d8247faa
--- /dev/null
+++ b/arch/i386/kernel/cpu/common.c
@@ -0,0 +1,634 @@
+#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 <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 desc_struct, cpu_gdt_table[GDT_ENTRIES]);
+EXPORT_PER_CPU_SYMBOL(cpu_gdt_table);
+
+DEFINE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
+EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
+
+static int cachesize_override __initdata = -1;
+static int disable_x86_fxsr __initdata = 0;
+static int disable_x86_serial_nr __initdata = 1;
+
+struct cpu_dev * cpu_devs[X86_VENDOR_NUM] = {};
+
+extern void mcheck_init(struct cpuinfo_x86 *c);
+
+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,
+};
+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 __init 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 __init 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 __init *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 */
+}
+
+
+void __init get_cpu_vendor(struct cpuinfo_x86 *c, int early)
+{
+ char *v = c->x86_vendor_id;
+ int i;
+
+ 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];
+ break;
+ }
+ }
+ }
+}
+
+
+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 __init 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. */
+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;
+ c->x86_model += ((tfms >> 16) & 0xF) << 4;
+ }
+ c->x86_mask = tfms & 15;
+ if (cap0 & (1<<19))
+ c->x86_cache_alignment = ((misc >> 8) & 0xff) * 8;
+ }
+
+ early_intel_workaround(c);
+}
+
+void __init 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 */
+ }
+ }
+}
+
+static void __init 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 __init 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_num_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. */
+#ifdef CONFIG_X86_MCE
+ mcheck_init(c);
+#endif
+}
+
+#ifdef CONFIG_X86_HT
+void __init detect_ht(struct cpuinfo_x86 *c)
+{
+ u32 eax, ebx, ecx, edx;
+ int index_lsb, index_msb, tmp;
+ int cpu = smp_processor_id();
+
+ if (!cpu_has(c, X86_FEATURE_HT))
+ 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 ) {
+ index_lsb = 0;
+ index_msb = 31;
+
+ if (smp_num_siblings > NR_CPUS) {
+ printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
+ smp_num_siblings = 1;
+ return;
+ }
+ tmp = smp_num_siblings;
+ while ((tmp & 1) == 0) {
+ tmp >>=1 ;
+ index_lsb++;
+ }
+ tmp = smp_num_siblings;
+ while ((tmp & 0x80000000 ) == 0) {
+ tmp <<=1 ;
+ index_msb--;
+ }
+ if (index_lsb != index_msb )
+ index_msb++;
+ 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]);
+ }
+}
+#endif
+
+void __init 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 __initdata = 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 __init cpu_init (void)
+{
+ int cpu = smp_processor_id();
+ struct tss_struct * t = &per_cpu(init_tss, cpu);
+ struct thread_struct *thread = &current->thread;
+ __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, 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);
+ }
+
+ /*
+ * Initialize the per-CPU GDT with the boot GDT,
+ * and set up the GDT descriptor:
+ */
+ memcpy(&per_cpu(cpu_gdt_table, cpu), cpu_gdt_table,
+ GDT_SIZE);
+
+ /* Set up GDT entry for 16bit stack */
+ *(__u64 *)&(per_cpu(cpu_gdt_table, cpu)[GDT_ENTRY_ESPFIX_SS]) |=
+ ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
+ ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
+ (CPU_16BIT_STACK_SIZE - 1);
+
+ cpu_gdt_descr[cpu].size = GDT_SIZE - 1;
+ cpu_gdt_descr[cpu].address =
+ (unsigned long)&per_cpu(cpu_gdt_table, cpu);
+
+ /*
+ * Set up the per-thread TLS descriptor cache:
+ */
+ memcpy(thread->tls_array, &per_cpu(cpu_gdt_table, cpu),
+ GDT_ENTRY_TLS_ENTRIES * 8);
+
+ __asm__ __volatile__("lgdt %0" : : "m" (cpu_gdt_descr[cpu]));
+ __asm__ __volatile__("lidt %0" : : "m" (idt_descr));
+
+ /*
+ * Delete NT
+ */
+ __asm__("pushfl ; andl $0xffffbfff,(%esp) ; popfl");
+
+ /*
+ * 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);
+
+ /* Set up doublefault TSS pointer in the GDT */
+ __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
+
+ /* Clear %fs and %gs. */
+ asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
+
+ /* Clear all 6 debug registers: */
+
+#define CD(register) __asm__("movl %0,%%db" #register ::"r"(0) );
+
+ CD(0); CD(1); CD(2); CD(3); /* no db4 and db5 */; CD(6); CD(7);
+
+#undef CD
+
+ /*
+ * Force FPU initialization:
+ */
+ current_thread_info()->status = 0;
+ clear_used_math();
+ mxcsr_feature_mask_init();
+}