1 /* 2 hwmon-vid.c - VID/VRM/VRD voltage conversions 3 4 Copyright (c) 2004 Rudolf Marek <r.marek@sh.cvut.cz> 5 6 Partly imported from i2c-vid.h of the lm_sensors project 7 Copyright (c) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com> 8 With assistance from Trent Piepho <xyzzy@speakeasy.org> 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 2 of the License, or 13 (at your option) any later version. 14 15 This program is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with this program; if not, write to the Free Software 22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 23 */ 24 25 #include <linux/config.h> 26 #include <linux/module.h> 27 #include <linux/kernel.h> 28 #include <linux/hwmon-vid.h> 29 30 /* 31 Common code for decoding VID pins. 32 33 References: 34 35 For VRM 8.4 to 9.1, "VRM x.y DC-DC Converter Design Guidelines", 36 available at http://developer.intel.com/. 37 38 For VRD 10.0 and up, "VRD x.y Design Guide", 39 available at http://developer.intel.com/. 40 41 AMD Opteron processors don't follow the Intel specifications. 42 I'm going to "make up" 2.4 as the spec number for the Opterons. 43 No good reason just a mnemonic for the 24x Opteron processor 44 series. 45 46 Opteron VID encoding is: 47 00000 = 1.550 V 48 00001 = 1.525 V 49 . . . . 50 11110 = 0.800 V 51 11111 = 0.000 V (off) 52 53 The 17 specification is in fact Intel Mobile Voltage Positioning - 54 (IMVP-II). You can find more information in the datasheet of Max1718 55 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452 56 57 The 13 specification corresponds to the Intel Pentium M series. There 58 doesn't seem to be any named specification for these. The conversion 59 tables are detailed directly in the various Pentium M datasheets: 60 http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm 61 62 The 14 specification corresponds to Intel Core series. There 63 doesn't seem to be any named specification for these. The conversion 64 tables are detailed directly in the various Pentium Core datasheets: 65 http://www.intel.com/design/mobile/datashts/309221.htm 66 67 The 110 (VRM 11) specification corresponds to Intel Conroe based series. 68 http://www.intel.com/design/processor/applnots/313214.htm 69 */ 70 71 /* vrm is the VRM/VRD document version multiplied by 10. 72 val is the 4-bit or more VID code. 73 Returned value is in mV to avoid floating point in the kernel. 74 Some VID have some bits in uV scale, this is rounded to mV */ 75 int vid_from_reg(int val, u8 vrm) 76 { 77 int vid; 78 79 switch(vrm) { 80 81 case 100: /* VRD 10.0 */ 82 /* compute in uV, round to mV */ 83 val &= 0x3f; 84 if((val & 0x1f) == 0x1f) 85 return 0; 86 if((val & 0x1f) <= 0x09 || val == 0x0a) 87 vid = 1087500 - (val & 0x1f) * 25000; 88 else 89 vid = 1862500 - (val & 0x1f) * 25000; 90 if(val & 0x20) 91 vid -= 12500; 92 return((vid + 500) / 1000); 93 94 case 110: /* Intel Conroe */ 95 /* compute in uV, round to mV */ 96 val &= 0xff; 97 if(((val & 0x7e) == 0xfe) || (!(val & 0x7e))) 98 return 0; 99 return((1600000 - (val - 2) * 6250 + 500) / 1000); 100 case 24: /* Opteron processor */ 101 val &= 0x1f; 102 return(val == 0x1f ? 0 : 1550 - val * 25); 103 104 case 91: /* VRM 9.1 */ 105 case 90: /* VRM 9.0 */ 106 val &= 0x1f; 107 return(val == 0x1f ? 0 : 108 1850 - val * 25); 109 110 case 85: /* VRM 8.5 */ 111 val &= 0x1f; 112 return((val & 0x10 ? 25 : 0) + 113 ((val & 0x0f) > 0x04 ? 2050 : 1250) - 114 ((val & 0x0f) * 50)); 115 116 case 84: /* VRM 8.4 */ 117 val &= 0x0f; 118 /* fall through */ 119 case 82: /* VRM 8.2 */ 120 val &= 0x1f; 121 return(val == 0x1f ? 0 : 122 val & 0x10 ? 5100 - (val) * 100 : 123 2050 - (val) * 50); 124 case 17: /* Intel IMVP-II */ 125 val &= 0x1f; 126 return(val & 0x10 ? 975 - (val & 0xF) * 25 : 127 1750 - val * 50); 128 case 13: 129 val &= 0x3f; 130 return(1708 - val * 16); 131 case 14: /* Intel Core */ 132 /* compute in uV, round to mV */ 133 val &= 0x7f; 134 return(val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000); 135 default: /* report 0 for unknown */ 136 printk(KERN_INFO "hwmon-vid: requested unknown VRM version\n"); 137 return 0; 138 } 139 } 140 141 142 /* 143 After this point is the code to automatically determine which 144 VRM/VRD specification should be used depending on the CPU. 145 */ 146 147 struct vrm_model { 148 u8 vendor; 149 u8 eff_family; 150 u8 eff_model; 151 u8 eff_stepping; 152 u8 vrm_type; 153 }; 154 155 #define ANY 0xFF 156 157 #ifdef CONFIG_X86 158 159 /* the stepping parameter is highest acceptable stepping for current line */ 160 161 static struct vrm_model vrm_models[] = { 162 {X86_VENDOR_AMD, 0x6, ANY, ANY, 90}, /* Athlon Duron etc */ 163 {X86_VENDOR_AMD, 0xF, ANY, ANY, 24}, /* Athlon 64, Opteron and above VRM 24 */ 164 {X86_VENDOR_INTEL, 0x6, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 165 {X86_VENDOR_INTEL, 0x6, 0xB, ANY, 85}, /* Tualatin */ 166 {X86_VENDOR_INTEL, 0x6, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 167 {X86_VENDOR_INTEL, 0x6, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 168 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, 110}, /* Intel Conroe */ 169 {X86_VENDOR_INTEL, 0x6, ANY, ANY, 82}, /* any P6 */ 170 {X86_VENDOR_INTEL, 0x7, ANY, ANY, 0}, /* Itanium */ 171 {X86_VENDOR_INTEL, 0xF, 0x0, ANY, 90}, /* P4 */ 172 {X86_VENDOR_INTEL, 0xF, 0x1, ANY, 90}, /* P4 Willamette */ 173 {X86_VENDOR_INTEL, 0xF, 0x2, ANY, 90}, /* P4 Northwood */ 174 {X86_VENDOR_INTEL, 0xF, ANY, ANY, 100}, /* Prescott and above assume VRD 10 */ 175 {X86_VENDOR_INTEL, 0x10, ANY, ANY, 0}, /* Itanium 2 */ 176 {X86_VENDOR_CENTAUR, 0x6, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 177 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x7, 85}, /* Ezra T */ 178 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x7, 85}, /* Nemiah */ 179 {X86_VENDOR_CENTAUR, 0x6, 0x9, ANY, 17}, /* C3-M */ 180 {X86_VENDOR_UNKNOWN, ANY, ANY, ANY, 0} /* stop here */ 181 }; 182 183 static u8 find_vrm(u8 eff_family, u8 eff_model, u8 eff_stepping, u8 vendor) 184 { 185 int i = 0; 186 187 while (vrm_models[i].vendor!=X86_VENDOR_UNKNOWN) { 188 if (vrm_models[i].vendor==vendor) 189 if ((vrm_models[i].eff_family==eff_family) 190 && ((vrm_models[i].eff_model==eff_model) || 191 (vrm_models[i].eff_model==ANY)) && 192 (eff_stepping <= vrm_models[i].eff_stepping)) 193 return vrm_models[i].vrm_type; 194 i++; 195 } 196 197 return 0; 198 } 199 200 u8 vid_which_vrm(void) 201 { 202 struct cpuinfo_x86 *c = cpu_data; 203 u32 eax; 204 u8 eff_family, eff_model, eff_stepping, vrm_ret; 205 206 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 207 return 0; /* doesn't have VID and/or CPUID */ 208 209 eax = cpuid_eax(1); 210 eff_family = ((eax & 0x00000F00)>>8); 211 eff_model = ((eax & 0x000000F0)>>4); 212 eff_stepping = eax & 0xF; 213 if (eff_family == 0xF) { /* use extended model & family */ 214 eff_family += ((eax & 0x00F00000)>>20); 215 eff_model += ((eax & 0x000F0000)>>16)<<4; 216 } 217 vrm_ret = find_vrm(eff_family, eff_model, eff_stepping, c->x86_vendor); 218 if (vrm_ret == 0) 219 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your " 220 "x86 CPU\n"); 221 return vrm_ret; 222 } 223 224 /* and now for something completely different for the non-x86 world */ 225 #else 226 u8 vid_which_vrm(void) 227 { 228 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your CPU\n"); 229 return 0; 230 } 231 #endif 232 233 EXPORT_SYMBOL(vid_from_reg); 234 EXPORT_SYMBOL(vid_which_vrm); 235 236 MODULE_AUTHOR("Rudolf Marek <r.marek@sh.cvut.cz>"); 237 238 MODULE_DESCRIPTION("hwmon-vid driver"); 239 MODULE_LICENSE("GPL"); 240