Quelle  intel_gsic.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  (C) 2003  Bruno Ducrot
 *  (C) 2004  Dominik Brodowski <linux@dominikbrodowski.de>
 *
 * Based on code found in
 * linux/include/asm-i386/ist.h and linux/arch/i386/kernel/setup.c
 * and originally developed by Andy Grover <andrew.grover@intel.com>
 */

#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\nspeedstep-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 "
         "dependent.\n");
 }
 return 1;
}