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 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