C语言调用Intel处理器CPUID指令的实例

来源 https://blog.csdn.net/subfate/article/details/50789905

在Linux环境下，使用C语言内嵌汇编的手段使用CPUID指令，进而在高级语言层面上看到获取的信息。

实现文件cpuid.c代码如下：

struct cpuid_result {

    uint32_t eax;

    uint32_t ebx;

    uint32_t ecx;

    uint32_t edx;

};

/*

* Generic CPUID function

*/

static inline struct cpuid_result cpuid(unsigned int op)

{

    struct cpuid_result result;

    __asm volatile(

        "mov %%ebx, %%edi;"

        "cpuid;"

        "mov %%ebx, %%esi;"

        "mov %%edi, %%ebx;"

        : "=a" (result.eax),

        "=S" (result.ebx),

        "=c" (result.ecx),

        "=d" (result.edx)

        : "" (op)

        : "edi");

    return result;

}

static inline unsigned int cpuid_eax(unsigned int op)

{

    //unsigned int eax, ebx, ecx, edx;

    struct cpuid_result regs;

    regs = cpuid(op);

    return regs.eax;

}

void get_cpu_vendor(char* cpu_vendor, unsigned int* cpuid_level)

{

    unsigned int cpuid_op = 0x00000000;

    char vendor_name[] = {'\0'};

    struct cpuid_result result;

    unsigned int level = ;

    vendor_name[] = '\0'; /* Unset */

    result = cpuid(cpuid_op); // eax为0表示读取vendor id，一共12字节，依次在ebx、edx、ecx。

    level = result.eax;

    vendor_name[] = (result.ebx >> ) & 0xff;

    vendor_name[] = (result.ebx >> ) & 0xff;

    vendor_name[] = (result.ebx >> ) & 0xff;

    vendor_name[] = (result.ebx >> ) & 0xff;

    vendor_name[] = (result.edx >> ) & 0xff;

    vendor_name[] = (result.edx >> ) & 0xff;

    vendor_name[] = (result.edx >> ) & 0xff;

    vendor_name[] = (result.edx >> ) & 0xff;

    vendor_name[] = (result.ecx >> ) & 0xff;

    vendor_name[] = (result.ecx >> ) & 0xff;

    vendor_name[] = (result.ecx >> ) & 0xff;

    vendor_name[] = (result.ecx >> ) & 0xff;

    vendor_name[] = '\0';

    strcpy(cpu_vendor, vendor_name);

    *cpuid_level = level;

}

void get_cpu_id(char* cpu_id, unsigned int* cpu_sign)

{

    unsigned int cpuid_op = 0x00000001;

    struct cpuid_result result;

    unsigned int sign = , id = ;

    unsigned int tmp = ;

    result = cpuid(cpuid_op);

    sign = result.eax;

    id = result.edx;

    sprintf(cpu_id, "%02X-%02X-%02X-%02X-%02X-%02X-%02X-%02X", (sign >> ) & 0xff, (sign >> ) & 0xff, (sign >> ) & 0xff, (sign >> ) & 0xff,

        (id >> ) & 0xff, (id >> ) & 0xff, (id >> ) & 0xff, (id >> ) & 0xff);

    *cpu_sign = sign;

}

struct cpuinfo_x86 {

    uint8_t    x86;        /* CPU family */

    uint8_t    x86_vendor;    /* CPU vendor */

    uint8_t    x86_model;  /* CPU model */

    uint8_t    x86_step;  /* CPU stepping */

};

// 参考IA32开发手册第2卷第3章。CPUID exa==0x01的图3-6

static inline void get_fms(struct cpuinfo_x86 *c, uint32_t tfms)

{

    c->x86 = (tfms >> ) & 0xf;

    c->x86_model = (tfms >> ) & 0xf;

    c->x86_step = tfms & 0xf;

    if (c->x86 == 0xf)

        c->x86 += (tfms >> ) & 0xff;

    if (c->x86 >= 0x6)

        c->x86_model += ((tfms >> ) & 0xF) << ;

}

void get_cpu_fms(unsigned int* family, unsigned int* model, unsigned int* stepping)

{

    unsigned int cpuid_op = 0x00000001;

    struct cpuinfo_x86 c;

    unsigned int ver = ;

    ver = cpuid_eax(cpuid_op);

    get_fms(&c, ver);

    *family = c.x86;

    *model = c.x86_model;

    *stepping = c.x86_step;

}

void get_cpu_name(char* processor_name)

{

    unsigned int cpuid_op = 0x80000002;

    struct cpuid_result regs;

    char temp_processor_name[];

    char* processor_name_start;

    unsigned int *name_as_ints = (unsigned int *)temp_processor_name;

    unsigned int i;

    /*

    用cpuid指令，eax传入0x80000002/0x80000003/0x80000004，

    共3个，每个4个寄存器，每个寄存器4字节，故一共48字节。

    参考IA32开发手册第2卷第3章。

    */

    for (i = ; i < ; i++) {

        regs = cpuid(cpuid_op + i);

        name_as_ints[i *  + ] = regs.eax;

        name_as_ints[i *  + ] = regs.ebx;

        name_as_ints[i *  + ] = regs.ecx;

        name_as_ints[i *  + ] = regs.edx;

    }

    temp_processor_name[] = '\0'; // 最后的字节为0，结束

    /* Skip leading spaces. */

    processor_name_start = temp_processor_name;

    while (*processor_name_start == ' ')

        processor_name_start++;

    memset(processor_name, , );

    strcpy(processor_name, processor_name_start);

}

void get_address_bits(unsigned int* linear, unsigned int* physical)

{

    unsigned int cpuid_op = 0x80000008;

    unsigned int tmp = ;

    tmp = cpuid_eax(cpuid_op);

    *linear = (tmp >> ) & 0xff;

    *physical = (tmp >> ) & 0xff;

}

主函数实现代码如下：

void get_hw_cpu(void)

{

    char buffer[] = { '\0' };

    unsigned int num = ;

    unsigned int f = , m = , s = ;

    unsigned int phy_bits = , vir_bits = ;

    memset((void *)buffer, '\0', sizeof(buffer));

    num = ;

    get_cpu_vendor(buffer, &num);

    fprintf(stdout, "vendor_id \t: %s\n", buffer);

    fprintf(stdout, "cpuid level \t: %u\n", num);

    memset((void *)buffer, '\0', sizeof(buffer));

    num = ;

    get_cpu_id(buffer, &num);

    fprintf(stdout, "cpu_id serial \t: %s\n", buffer);

    fprintf(stdout, "cpuid sign \t: %u\n", num);

    memset((void *)buffer, '\0', sizeof(buffer));

    get_cpu_name(buffer);

    fprintf(stdout, "model name \t: %s\n", buffer);

    get_cpu_fms(&f, &m, &s);

    fprintf(stdout, "cpu family \t: %u(0x%0X)\n", f, f);

    fprintf(stdout, "cpu model \t: %u(0x%0X)\n", m, m);

    fprintf(stdout, "cpu stepping \t: %u(0x%0X)\n", s, s);

    get_address_bits(&vir_bits, &phy_bits);

    fprintf(stdout, "address sizes \t: %u bits physical - %u bits virtual\n", phy_bits, vir_bits);

}

Intel处理器的CPUID远不止上文所述，详情请参考Intel IA32软件开发手册。

在GCC中获取CPUID信息（兼容VC） https://www.cnblogs.com/zyl910/archive/2012/08/06/getcpuid_gcc.html

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