source: mainline/kernel/arch/ia32/src/cpu/cpu.c@ 76fca31

/*
 * Copyright (c) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup ia32
 * @{
 */
/** @file
 */

#include <arch/cpu.h>
#include <arch/cpuid.h>
#include <arch/pm.h>

#include <arch.h>
#include <arch/types.h>
#include <print.h>
#include <fpu_context.h>

#include <arch/smp/apic.h>
#include <arch/syscall.h>

/*
 * Identification of CPUs.
 * Contains only non-MP-Specification specific SMP code.
 */
#define AMD_CPUID_EBX   0x68747541
#define AMD_CPUID_ECX   0x444d4163
#define AMD_CPUID_EDX   0x69746e65

#define INTEL_CPUID_EBX 0x756e6547
#define INTEL_CPUID_ECX 0x6c65746e
#define INTEL_CPUID_EDX 0x49656e69


enum vendor {
        VendorUnknown=0,
        VendorAMD,
        VendorIntel
};

static char *vendor_str[] = {
        "Unknown Vendor",
        "AMD",
        "Intel"
};

void fpu_disable(void)
{
        asm volatile (
                "mov %%cr0,%%eax;"
                "or $8,%%eax;"
                "mov %%eax,%%cr0;"
                :
                :
                : "%eax"
        );
}

void fpu_enable(void)
{
        asm volatile (
                "mov %%cr0,%%eax;"
                "and $0xffFFffF7,%%eax;"
                "mov %%eax,%%cr0;"
                :
                :
                : "%eax"
        );      
}

void cpu_arch_init(void)
{
        cpuid_feature_info fi;
        cpuid_extended_feature_info efi;
        cpu_info_t info;
        uint32_t help = 0;
        
        CPU->arch.tss = tss_p;
        CPU->arch.tss->iomap_base = &CPU->arch.tss->iomap[0] - ((uint8_t *) CPU->arch.tss);

        CPU->fpu_owner = NULL;

        cpuid(1, &info);

        fi.word = info.cpuid_edx;
        efi.word = info.cpuid_ecx;
        
        if (fi.bits.fxsr)
                fpu_fxsr();
        else
                fpu_fsr();      
        
        if (fi.bits.sse) {
                asm volatile (
                        "mov %%cr4,%0\n"
                        "or %1,%0\n"
                        "mov %0,%%cr4\n"
                        : "+r" (help)
                        : "i" (CR4_OSFXSR_MASK|(1<<10)) 
                );
        }
        
        /* Setup fast SYSENTER/SYSEXIT syscalls */
        syscall_setup_cpu();
}

void cpu_identify(void)
{
        cpu_info_t info;

        CPU->arch.vendor = VendorUnknown;
        if (has_cpuid()) {
                cpuid(0, &info);

                /*
                 * Check for AMD processor.
                 */
                if ((info.cpuid_ebx == AMD_CPUID_EBX)
                    && (info.cpuid_ecx == AMD_CPUID_ECX)
                        && (info.cpuid_edx == AMD_CPUID_EDX))
                        CPU->arch.vendor = VendorAMD;
                
                /*
                 * Check for Intel processor.
                 */             
                if ((info.cpuid_ebx == INTEL_CPUID_EBX)
                    && (info.cpuid_ecx == INTEL_CPUID_ECX)
                        && (info.cpuid_edx == INTEL_CPUID_EDX))
                        CPU->arch.vendor = VendorIntel;
                
                cpuid(1, &info);
                CPU->arch.family = (info.cpuid_eax >> 8) & 0x0f;
                CPU->arch.model = (info.cpuid_eax >> 4) & 0x0f;
                CPU->arch.stepping = (info.cpuid_eax >> 0) & 0x0f;                                              
        }
}

void cpu_print_report(cpu_t* cpu)
{
        printf("cpu%u: (%s family=%u model=%u stepping=%u) %" PRIu16 " MHz\n",
                cpu->id, vendor_str[cpu->arch.vendor], cpu->arch.family,
                cpu->arch.model, cpu->arch.stepping, cpu->frequency_mhz);
}

/** @}
 */