intel_gsic.c

Go to the documentation of this file.

/*
 *  (C) 2003  Bruno Ducrot
 *  (C) 2004  Dominik Brodowski <[email protected]>
 *
 *  Licensed under the terms of the GNU GPL License version 2.
 *
 * Based on code found in
 * linux/include/asm-i386/ist.h and linux/arch/i386/kernel/setup.c
 * and originally developed by Andy Grover <[email protected]>
 */

#include <stdio.h>
#include <string.h>
#include <lrmi.h>

int main (void)
{
    struct LRMI_regs    r;
    int         retval;

    if (!LRMI_init())
        return 0;

    memset(&r, 0, sizeof(r));

    r.eax = 0x0000E980;
    r.edx = 0x47534943;

    retval = LRMI_int(0x15, &r);

    if (!retval) {
        printf("Failed!\n");
        return 0;
    }
    if (r.eax == 0x47534943) {
        printf("BIOS supports GSIC call:\n");
        printf("\tsignature: %c%c%c%c\n",
               (r.eax >> 24) & 0xff,
               (r.eax >> 16) & 0xff,
               (r.eax >> 8) & 0xff,
               (r.eax) & 0xff);
        printf("\tcommand port = 0x%.4x\n",
               r.ebx & 0xffff);
        printf("\tcommand =      0x%.4x\n",
               (r.ebx >> 16) & 0xffff);
        printf("\tevent port =   0x%.8x\n", r.ecx);
        printf("\tflags =        0x%.8x\n", r.edx);
        if (((r.ebx >> 16) & 0xffff) != 0x82) {
            printf("non-default command value. If speedstep-smi "
                   "doesn't work out of the box,\nyou may want to "
                   "try out the default value by passing "
                   "smi_cmd=0x82 to the module\n ON YOUR OWN "
                   "RISK.\n");
        }
        if ((r.ebx & 0xffff) != 0xb2) {
            printf("non-default command port. If speedstep-smi "
                   "doesn't work out of the box,\nyou may want to "
                   "try out the default value by passing "
                   "smi_port=0x82 to the module\n ON YOUR OWN "
                   "RISK.\n");
        }
    } else {
        printf("BIOS DOES NOT support GSIC call.  Dumping registers anyway:\n");
        printf("eax = 0x%.8x\n", r.eax);
        printf("ebx = 0x%.8x\n", r.ebx);
        printf("ecx = 0x%.8x\n", r.ecx);
        printf("edx = 0x%.8x\n", r.edx);
        printf("Note also that some BIOS do not support the initial "
               "GSIC call, but the newer\nspeeedstep-smi driver may "
               "work.\nFor this, you need to pass some arguments to "
               "the speedstep-smi driver:\n");
        printf("\tsmi_cmd=0x?? smi_port=0x?? smi_sig=1\n");
        printf("\nUnfortunately, you have to know what exactly are "
               "smi_cmd and smi_port, and this\nis system "
               "dependant.\n");
    }
    return 1;
}