1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * (C) 2003 Bruno Ducrot
4 * (C) 2004 Dominik Brodowski <linux@dominikbrodowski.de>
5 *
6 * Based on code found in
7 * linux/include/asm-i386/ist.h and linux/arch/i386/kernel/setup.c
8 * and originally developed by Andy Grover <andrew.grover@intel.com>
9 */
10
11 #include <stdio.h>
12 #include <string.h>
13 #include <lrmi.h>
14
main(void)15 int main (void)
16 {
17 struct LRMI_regs r;
18 int retval;
19
20 if (!LRMI_init())
21 return 0;
22
23 memset(&r, 0, sizeof(r));
24
25 r.eax = 0x0000E980;
26 r.edx = 0x47534943;
27
28 retval = LRMI_int(0x15, &r);
29
30 if (!retval) {
31 printf("Failed!\n");
32 return 0;
33 }
34 if (r.eax == 0x47534943) {
35 printf("BIOS supports GSIC call:\n");
36 printf("\tsignature: %c%c%c%c\n",
37 (r.eax >> 24) & 0xff,
38 (r.eax >> 16) & 0xff,
39 (r.eax >> 8) & 0xff,
40 (r.eax) & 0xff);
41 printf("\tcommand port = 0x%.4x\n",
42 r.ebx & 0xffff);
43 printf("\tcommand = 0x%.4x\n",
44 (r.ebx >> 16) & 0xffff);
45 printf("\tevent port = 0x%.8x\n", r.ecx);
46 printf("\tflags = 0x%.8x\n", r.edx);
47 if (((r.ebx >> 16) & 0xffff) != 0x82) {
48 printf("non-default command value. If speedstep-smi "
49 "doesn't work out of the box,\nyou may want to "
50 "try out the default value by passing "
51 "smi_cmd=0x82 to the module\n ON YOUR OWN "
52 "RISK.\n");
53 }
54 if ((r.ebx & 0xffff) != 0xb2) {
55 printf("non-default command port. If speedstep-smi "
56 "doesn't work out of the box,\nyou may want to "
57 "try out the default value by passing "
58 "smi_port=0x82 to the module\n ON YOUR OWN "
59 "RISK.\n");
60 }
61 } else {
62 printf("BIOS DOES NOT support GSIC call. Dumping registers anyway:\n");
63 printf("eax = 0x%.8x\n", r.eax);
64 printf("ebx = 0x%.8x\n", r.ebx);
65 printf("ecx = 0x%.8x\n", r.ecx);
66 printf("edx = 0x%.8x\n", r.edx);
67 printf("Note also that some BIOS do not support the initial "
68 "GSIC call, but the newer\nspeedstep-smi driver may "
69 "work.\nFor this, you need to pass some arguments to "
70 "the speedstep-smi driver:\n");
71 printf("\tsmi_cmd=0x?? smi_port=0x?? smi_sig=1\n");
72 printf("\nUnfortunately, you have to know what exactly are "
73 "smi_cmd and smi_port, and this\nis system "
74 "dependent.\n");
75 }
76 return 1;
77 }
78