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 Athlon 64 and AMD Opteron Processors, AMD Publication 26094, 41 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF 42 * Table 74. VID Code Voltages 43 * This corresponds to an arbitrary VRM code of 24 in the functions below. 44 * These CPU models (K8 revision <= E) have 5 VID pins. See also: 45 * Revision Guide for AMD Athlon 64 and AMD Opteron Processors, AMD Publication 25759, 46 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25759.pdf 47 * 48 * AMD NPT Family 0Fh Processors, AMD Publication 32559, 49 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/32559.pdf 50 * Table 71. VID Code Voltages 51 * This corresponds to an arbitrary VRM code of 25 in the functions below. 52 * These CPU models (K8 revision >= F) have 6 VID pins. See also: 53 * Revision Guide for AMD NPT Family 0Fh Processors, AMD Publication 33610, 54 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/33610.pdf 55 * 56 * The 17 specification is in fact Intel Mobile Voltage Positioning - 57 * (IMVP-II). You can find more information in the datasheet of Max1718 58 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452 59 * 60 * The 13 specification corresponds to the Intel Pentium M series. There 61 * doesn't seem to be any named specification for these. The conversion 62 * tables are detailed directly in the various Pentium M datasheets: 63 * http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm 64 * 65 * The 14 specification corresponds to Intel Core series. There 66 * doesn't seem to be any named specification for these. The conversion 67 * tables are detailed directly in the various Pentium Core datasheets: 68 * http://www.intel.com/design/mobile/datashts/309221.htm 69 * 70 * The 110 (VRM 11) specification corresponds to Intel Conroe based series. 71 * http://www.intel.com/design/processor/applnots/313214.htm 72 */ 73 74 /* 75 * vrm is the VRM/VRD document version multiplied by 10. 76 * val is the 4-bit or more VID code. 77 * Returned value is in mV to avoid floating point in the kernel. 78 * Some VID have some bits in uV scale, this is rounded to mV. 79 */ 80 int vid_from_reg(int val, u8 vrm) 81 { 82 int vid; 83 84 switch(vrm) { 85 86 case 100: /* VRD 10.0 */ 87 /* compute in uV, round to mV */ 88 val &= 0x3f; 89 if((val & 0x1f) == 0x1f) 90 return 0; 91 if((val & 0x1f) <= 0x09 || val == 0x0a) 92 vid = 1087500 - (val & 0x1f) * 25000; 93 else 94 vid = 1862500 - (val & 0x1f) * 25000; 95 if(val & 0x20) 96 vid -= 12500; 97 return((vid + 500) / 1000); 98 99 case 110: /* Intel Conroe */ 100 /* compute in uV, round to mV */ 101 val &= 0xff; 102 if (val < 0x02 || val > 0xb2) 103 return 0; 104 return((1600000 - (val - 2) * 6250 + 500) / 1000); 105 106 case 24: /* Athlon64 & Opteron */ 107 val &= 0x1f; 108 if (val == 0x1f) 109 return 0; 110 /* fall through */ 111 case 25: /* AMD NPT 0Fh */ 112 val &= 0x3f; 113 return (val < 32) ? 1550 - 25 * val 114 : 775 - (25 * (val - 31)) / 2; 115 116 case 91: /* VRM 9.1 */ 117 case 90: /* VRM 9.0 */ 118 val &= 0x1f; 119 return(val == 0x1f ? 0 : 120 1850 - val * 25); 121 122 case 85: /* VRM 8.5 */ 123 val &= 0x1f; 124 return((val & 0x10 ? 25 : 0) + 125 ((val & 0x0f) > 0x04 ? 2050 : 1250) - 126 ((val & 0x0f) * 50)); 127 128 case 84: /* VRM 8.4 */ 129 val &= 0x0f; 130 /* fall through */ 131 case 82: /* VRM 8.2 */ 132 val &= 0x1f; 133 return(val == 0x1f ? 0 : 134 val & 0x10 ? 5100 - (val) * 100 : 135 2050 - (val) * 50); 136 case 17: /* Intel IMVP-II */ 137 val &= 0x1f; 138 return(val & 0x10 ? 975 - (val & 0xF) * 25 : 139 1750 - val * 50); 140 case 13: 141 val &= 0x3f; 142 return(1708 - val * 16); 143 case 14: /* Intel Core */ 144 /* compute in uV, round to mV */ 145 val &= 0x7f; 146 return(val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000); 147 default: /* report 0 for unknown */ 148 if (vrm) 149 printk(KERN_WARNING "hwmon-vid: Requested unsupported " 150 "VRM version (%u)\n", (unsigned int)vrm); 151 return 0; 152 } 153 } 154 155 156 /* 157 * After this point is the code to automatically determine which 158 * VRM/VRD specification should be used depending on the CPU. 159 */ 160 161 struct vrm_model { 162 u8 vendor; 163 u8 eff_family; 164 u8 eff_model; 165 u8 eff_stepping; 166 u8 vrm_type; 167 }; 168 169 #define ANY 0xFF 170 171 #ifdef CONFIG_X86 172 173 /* 174 * The stepping parameter is highest acceptable stepping for current line. 175 * The model match must be exact for 4-bit values. For model values 0x10 176 * and above (extended model), all models below the parameter will match. 177 */ 178 179 static struct vrm_model vrm_models[] = { 180 {X86_VENDOR_AMD, 0x6, ANY, ANY, 90}, /* Athlon Duron etc */ 181 {X86_VENDOR_AMD, 0xF, 0x3F, ANY, 24}, /* Athlon 64, Opteron */ 182 {X86_VENDOR_AMD, 0xF, ANY, ANY, 25}, /* NPT family 0Fh */ 183 {X86_VENDOR_AMD, 0x10, ANY, ANY, 25}, /* NPT family 10h */ 184 {X86_VENDOR_INTEL, 0x6, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 185 {X86_VENDOR_INTEL, 0x6, 0xB, ANY, 85}, /* Tualatin */ 186 {X86_VENDOR_INTEL, 0x6, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 187 {X86_VENDOR_INTEL, 0x6, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 188 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, 110}, /* Intel Conroe */ 189 {X86_VENDOR_INTEL, 0x6, ANY, ANY, 82}, /* any P6 */ 190 {X86_VENDOR_INTEL, 0xF, 0x0, ANY, 90}, /* P4 */ 191 {X86_VENDOR_INTEL, 0xF, 0x1, ANY, 90}, /* P4 Willamette */ 192 {X86_VENDOR_INTEL, 0xF, 0x2, ANY, 90}, /* P4 Northwood */ 193 {X86_VENDOR_INTEL, 0xF, ANY, ANY, 100}, /* Prescott and above assume VRD 10 */ 194 {X86_VENDOR_CENTAUR, 0x6, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 195 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x7, 85}, /* Ezra T */ 196 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x7, 85}, /* Nemiah */ 197 {X86_VENDOR_CENTAUR, 0x6, 0x9, ANY, 17}, /* C3-M, Eden-N */ 198 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0x7, 0}, /* No information */ 199 {X86_VENDOR_CENTAUR, 0x6, 0xA, ANY, 13}, /* C7, Esther */ 200 {X86_VENDOR_UNKNOWN, ANY, ANY, ANY, 0} /* stop here */ 201 }; 202 203 static u8 find_vrm(u8 eff_family, u8 eff_model, u8 eff_stepping, u8 vendor) 204 { 205 int i = 0; 206 207 while (vrm_models[i].vendor!=X86_VENDOR_UNKNOWN) { 208 if (vrm_models[i].vendor==vendor) 209 if ((vrm_models[i].eff_family==eff_family) 210 && ((vrm_models[i].eff_model==eff_model) || 211 (vrm_models[i].eff_model >= 0x10 && 212 eff_model <= vrm_models[i].eff_model) || 213 (vrm_models[i].eff_model==ANY)) && 214 (eff_stepping <= vrm_models[i].eff_stepping)) 215 return vrm_models[i].vrm_type; 216 i++; 217 } 218 219 return 0; 220 } 221 222 u8 vid_which_vrm(void) 223 { 224 struct cpuinfo_x86 *c = &cpu_data(0); 225 u32 eax; 226 u8 eff_family, eff_model, eff_stepping, vrm_ret; 227 228 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 229 return 0; /* doesn't have VID and/or CPUID */ 230 231 eax = cpuid_eax(1); 232 eff_family = ((eax & 0x00000F00)>>8); 233 eff_model = ((eax & 0x000000F0)>>4); 234 eff_stepping = eax & 0xF; 235 if (eff_family == 0xF) { /* use extended model & family */ 236 eff_family += ((eax & 0x00F00000)>>20); 237 eff_model += ((eax & 0x000F0000)>>16)<<4; 238 } 239 vrm_ret = find_vrm(eff_family, eff_model, eff_stepping, c->x86_vendor); 240 if (vrm_ret == 0) 241 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your " 242 "x86 CPU\n"); 243 return vrm_ret; 244 } 245 246 /* and now for something completely different for the non-x86 world */ 247 #else 248 u8 vid_which_vrm(void) 249 { 250 printk(KERN_INFO "hwmon-vid: Unknown VRM version of your CPU\n"); 251 return 0; 252 } 253 #endif 254 255 EXPORT_SYMBOL(vid_from_reg); 256 EXPORT_SYMBOL(vid_which_vrm); 257 258 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); 259 260 MODULE_DESCRIPTION("hwmon-vid driver"); 261 MODULE_LICENSE("GPL"); 262