1 /* 2 hwmon-vid.c - VID/VRM/VRD voltage conversions 3 4 Copyright (c) 2004 Rudolf Marek <r.marek@assembler.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/module.h> 26 #include <linux/kernel.h> 27 #include <linux/hwmon-vid.h> 28 29 /* 30 Common code for decoding VID pins. 31 32 References: 33 34 For VRM 8.4 to 9.1, "VRM x.y DC-DC Converter Design Guidelines", 35 available at http://developer.intel.com/. 36 37 For VRD 10.0 and up, "VRD x.y Design Guide", 38 available at http://developer.intel.com/. 39 40 AMD Opteron processors don't follow the Intel specifications. 41 I'm going to "make up" 2.4 as the spec number for the Opterons. 42 No good reason just a mnemonic for the 24x Opteron processor 43 series. 44 45 Opteron VID encoding is: 46 00000 = 1.550 V 47 00001 = 1.525 V 48 . . . . 49 11110 = 0.800 V 50 11111 = 0.000 V (off) 51 52 The 17 specification is in fact Intel Mobile Voltage Positioning - 53 (IMVP-II). You can find more information in the datasheet of Max1718 54 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452 55 56 The 13 specification corresponds to the Intel Pentium M series. There 57 doesn't seem to be any named specification for these. The conversion 58 tables are detailed directly in the various Pentium M datasheets: 59 http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm 60 61 The 14 specification corresponds to Intel Core series. There 62 doesn't seem to be any named specification for these. The conversion 63 tables are detailed directly in the various Pentium Core datasheets: 64 http://www.intel.com/design/mobile/datashts/309221.htm 65 66 The 110 (VRM 11) specification corresponds to Intel Conroe based series. 67 http://www.intel.com/design/processor/applnots/313214.htm 68 */ 69 70 /* vrm is the VRM/VRD document version multiplied by 10. 71 val is the 4-bit or more VID code. 72 Returned value is in mV to avoid floating point in the kernel. 73 Some VID have some bits in uV scale, this is rounded to mV */ 74 int vid_from_reg(int val, u8 vrm) 75 { 76 int vid; 77 78 switch(vrm) { 79 80 case 100: /* VRD 10.0 */ 81 /* compute in uV, round to mV */ 82 val &= 0x3f; 83 if((val & 0x1f) == 0x1f) 84 return 0; 85 if((val & 0x1f) <= 0x09 || val == 0x0a) 86 vid = 1087500 - (val & 0x1f) * 25000; 87 else 88 vid = 1862500 - (val & 0x1f) * 25000; 89 if(val & 0x20) 90 vid -= 12500; 91 return((vid + 500) / 1000); 92 93 case 110: /* Intel Conroe */ 94 /* compute in uV, round to mV */ 95 val &= 0xff; 96 if (val < 0x02 || val > 0xb2) 97 return 0; 98 return((1600000 - (val - 2) * 6250 + 500) / 1000); 99 case 24: /* Opteron processor */ 100 val &= 0x1f; 101 return(val == 0x1f ? 0 : 1550 - val * 25); 102 103 case 91: /* VRM 9.1 */ 104 case 90: /* VRM 9.0 */ 105 val &= 0x1f; 106 return(val == 0x1f ? 0 : 107 1850 - val * 25); 108 109 case 85: /* VRM 8.5 */ 110 val &= 0x1f; 111 return((val & 0x10 ? 25 : 0) + 112 ((val & 0x0f) > 0x04 ? 2050 : 1250) - 113 ((val & 0x0f) * 50)); 114 115 case 84: /* VRM 8.4 */ 116 val &= 0x0f; 117 /* fall through */ 118 case 82: /* VRM 8.2 */ 119 val &= 0x1f; 120 return(val == 0x1f ? 0 : 121 val & 0x10 ? 5100 - (val) * 100 : 122 2050 - (val) * 50); 123 case 17: /* Intel IMVP-II */ 124 val &= 0x1f; 125 return(val & 0x10 ? 975 - (val & 0xF) * 25 : 126 1750 - val * 50); 127 case 13: 128 val &= 0x3f; 129 return(1708 - val * 16); 130 case 14: /* Intel Core */ 131 /* compute in uV, round to mV */ 132 val &= 0x7f; 133 return(val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000); 134 default: /* report 0 for unknown */ 135 if (vrm) 136 printk(KERN_WARNING "hwmon-vid: Requested unsupported " 137 "VRM version (%u)\n", (unsigned int)vrm); 138 return 0; 139 } 140 } 141 142 143 /* 144 After this point is the code to automatically determine which 145 VRM/VRD specification should be used depending on the CPU. 146 */ 147 148 struct vrm_model { 149 u8 vendor; 150 u8 eff_family; 151 u8 eff_model; 152 u8 eff_stepping; 153 u8 vrm_type; 154 }; 155 156 #define ANY 0xFF 157 158 #ifdef CONFIG_X86 159 160 /* the stepping parameter is highest acceptable stepping for current line */ 161 162 static struct vrm_model vrm_models[] = { 163 {X86_VENDOR_AMD, 0x6, ANY, ANY, 90}, /* Athlon Duron etc */ 164 {X86_VENDOR_AMD, 0xF, ANY, ANY, 24}, /* Athlon 64, Opteron and above VRM 24 */ 165 {X86_VENDOR_INTEL, 0x6, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 166 {X86_VENDOR_INTEL, 0x6, 0xB, ANY, 85}, /* Tualatin */ 167 {X86_VENDOR_INTEL, 0x6, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 168 {X86_VENDOR_INTEL, 0x6, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 169 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, 110}, /* Intel Conroe */ 170 {X86_VENDOR_INTEL, 0x6, ANY, ANY, 82}, /* any P6 */ 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_CENTAUR, 0x6, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 176 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x7, 85}, /* Ezra T */ 177 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x7, 85}, /* Nemiah */ 178 {X86_VENDOR_CENTAUR, 0x6, 0x9, ANY, 17}, /* C3-M, Eden-N */ 179 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0x7, 0}, /* No information */ 180 {X86_VENDOR_CENTAUR, 0x6, 0xA, ANY, 13}, /* C7, Esther */ 181 {X86_VENDOR_UNKNOWN, ANY, ANY, ANY, 0} /* stop here */ 182 }; 183 184 static u8 find_vrm(u8 eff_family, u8 eff_model, u8 eff_stepping, u8 vendor) 185 { 186 int i = 0; 187 188 while (vrm_models[i].vendor!=X86_VENDOR_UNKNOWN) { 189 if (vrm_models[i].vendor==vendor) 190 if ((vrm_models[i].eff_family==eff_family) 191 && ((vrm_models[i].eff_model==eff_model) || 192 (vrm_models[i].eff_model==ANY)) && 193 (eff_stepping <= vrm_models[i].eff_stepping)) 194 return vrm_models[i].vrm_type; 195 i++; 196 } 197 198 return 0; 199 } 200 201 u8 vid_which_vrm(void) 202 { 203 struct cpuinfo_x86 *c = &cpu_data(0); 204 u32 eax; 205 u8 eff_family, eff_model, eff_stepping, vrm_ret; 206 207 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 208 return 0; /* doesn't have VID and/or CPUID */ 209 210 eax = cpuid_eax(1); 211 eff_family = ((eax & 0x00000F00)>>8); 212 eff_model = ((eax & 0x000000F0)>>4); 213 eff_stepping = eax & 0xF; 214 if (eff_family == 0xF) { /* use extended model & family */ 215 eff_family += ((eax & 0x00F00000)>>20); 216 eff_model += ((eax & 0x000F0000)>>16)<<4; 217 } 218 vrm_ret = find_vrm(eff_family, eff_model, eff_stepping, c->x86_vendor); 219 if (vrm_ret == 0) 220 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your " 221 "x86 CPU\n"); 222 return vrm_ret; 223 } 224 225 /* and now for something completely different for the non-x86 world */ 226 #else 227 u8 vid_which_vrm(void) 228 { 229 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your CPU\n"); 230 return 0; 231 } 232 #endif 233 234 EXPORT_SYMBOL(vid_from_reg); 235 EXPORT_SYMBOL(vid_which_vrm); 236 237 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); 238 239 MODULE_DESCRIPTION("hwmon-vid driver"); 240 MODULE_LICENSE("GPL"); 241