source: bootcd/isolinux/syslinux-6.03/gpxe/src/arch/i386/include/bits/cpu.h

#ifndef I386_BITS_CPU_H
#define I386_BITS_CPU_H

/* Intel-defined CPU features, CPUID level 0x00000001, word 0 */
#define X86_FEATURE_FPU         0 /* Onboard FPU */
#define X86_FEATURE_VME         1 /* Virtual Mode Extensions */
#define X86_FEATURE_DE          2 /* Debugging Extensions */
#define X86_FEATURE_PSE         3 /* Page Size Extensions */
#define X86_FEATURE_TSC         4 /* Time Stamp Counter */
#define X86_FEATURE_MSR         5 /* Model-Specific Registers, RDMSR, WRMSR */
#define X86_FEATURE_PAE         6 /* Physical Address Extensions */
#define X86_FEATURE_MCE         7 /* Machine Check Architecture */
#define X86_FEATURE_CX8         8 /* CMPXCHG8 instruction */
#define X86_FEATURE_APIC        9 /* Onboard APIC */
#define X86_FEATURE_SEP         11 /* SYSENTER/SYSEXIT */
#define X86_FEATURE_MTRR        12 /* Memory Type Range Registers */
#define X86_FEATURE_PGE         13 /* Page Global Enable */
#define X86_FEATURE_MCA         14 /* Machine Check Architecture */
#define X86_FEATURE_CMOV        15 /* CMOV instruction (FCMOVCC and FCOMI too if FPU present) */
#define X86_FEATURE_PAT         16 /* Page Attribute Table */
#define X86_FEATURE_PSE36       17 /* 36-bit PSEs */
#define X86_FEATURE_PN          18 /* Processor serial number */
#define X86_FEATURE_CLFLSH      19 /* Supports the CLFLUSH instruction */
#define X86_FEATURE_DTES        21 /* Debug Trace Store */
#define X86_FEATURE_ACPI        22 /* ACPI via MSR */
#define X86_FEATURE_MMX         23 /* Multimedia Extensions */
#define X86_FEATURE_FXSR        24 /* FXSAVE and FXRSTOR instructions (fast save and restore */
                                          /* of FPU context), and CR4.OSFXSR available */
#define X86_FEATURE_XMM         25 /* Streaming SIMD Extensions */
#define X86_FEATURE_XMM2        26 /* Streaming SIMD Extensions-2 */
#define X86_FEATURE_SELFSNOOP   27 /* CPU self snoop */
#define X86_FEATURE_HT          28 /* Hyper-Threading */
#define X86_FEATURE_ACC         29 /* Automatic clock control */
#define X86_FEATURE_IA64        30 /* IA-64 processor */

/* AMD-defined CPU features, CPUID level 0x80000001, word 1 */
/* Don't duplicate feature flags which are redundant with Intel! */
#define X86_FEATURE_SYSCALL     11 /* SYSCALL/SYSRET */
#define X86_FEATURE_MMXEXT      22 /* AMD MMX extensions */
#define X86_FEATURE_LM          29 /* Long Mode (x86-64) */
#define X86_FEATURE_3DNOWEXT    30 /* AMD 3DNow! extensions */
#define X86_FEATURE_3DNOW       31 /* 3DNow! */

/** x86 CPU information */
struct cpuinfo_x86 {
        /** CPU features */
        unsigned int features;
        /** 64-bit CPU features */
        unsigned int amd_features;
};

/*
 * EFLAGS bits
 */
#define X86_EFLAGS_CF   0x00000001 /* Carry Flag */
#define X86_EFLAGS_PF   0x00000004 /* Parity Flag */
#define X86_EFLAGS_AF   0x00000010 /* Auxillary carry Flag */
#define X86_EFLAGS_ZF   0x00000040 /* Zero Flag */
#define X86_EFLAGS_SF   0x00000080 /* Sign Flag */
#define X86_EFLAGS_TF   0x00000100 /* Trap Flag */
#define X86_EFLAGS_IF   0x00000200 /* Interrupt Flag */
#define X86_EFLAGS_DF   0x00000400 /* Direction Flag */
#define X86_EFLAGS_OF   0x00000800 /* Overflow Flag */
#define X86_EFLAGS_IOPL 0x00003000 /* IOPL mask */
#define X86_EFLAGS_NT   0x00004000 /* Nested Task */
#define X86_EFLAGS_RF   0x00010000 /* Resume Flag */
#define X86_EFLAGS_VM   0x00020000 /* Virtual Mode */
#define X86_EFLAGS_AC   0x00040000 /* Alignment Check */
#define X86_EFLAGS_VIF  0x00080000 /* Virtual Interrupt Flag */
#define X86_EFLAGS_VIP  0x00100000 /* Virtual Interrupt Pending */
#define X86_EFLAGS_ID   0x00200000 /* CPUID detection flag */

/*
 * Generic CPUID function
 */
static inline __attribute__ (( always_inline )) void
cpuid ( int op, unsigned int *eax, unsigned int *ebx,
        unsigned int *ecx, unsigned int *edx ) {
        __asm__ ( "cpuid" :
                  "=a" ( *eax ), "=b" ( *ebx ), "=c" ( *ecx ), "=d" ( *edx )
                : "0" ( op ) );
}

extern void get_cpuinfo ( struct cpuinfo_x86 *cpu );

#endif /* I386_BITS_CPU_H */