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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 26 27 #include <linux/module.h> 28 #include <linux/kernel.h> 29 #include <linux/hwmon-vid.h> 30 31 /* 32 * Common code for decoding VID pins. 33 * 34 * References: 35 * 36 * For VRM 8.4 to 9.1, "VRM x.y DC-DC Converter Design Guidelines", 37 * available at http://developer.intel.com/. 38 * 39 * For VRD 10.0 and up, "VRD x.y Design Guide", 40 * available at http://developer.intel.com/. 41 * 42 * AMD Athlon 64 and AMD Opteron Processors, AMD Publication 26094, 43 * http://support.amd.com/us/Processor_TechDocs/26094.PDF 44 * Table 74. VID Code Voltages 45 * This corresponds to an arbitrary VRM code of 24 in the functions below. 46 * These CPU models (K8 revision <= E) have 5 VID pins. See also: 47 * Revision Guide for AMD Athlon 64 and AMD Opteron Processors, AMD Publication 25759, 48 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25759.pdf 49 * 50 * AMD NPT Family 0Fh Processors, AMD Publication 32559, 51 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/32559.pdf 52 * Table 71. VID Code Voltages 53 * This corresponds to an arbitrary VRM code of 25 in the functions below. 54 * These CPU models (K8 revision >= F) have 6 VID pins. See also: 55 * Revision Guide for AMD NPT Family 0Fh Processors, AMD Publication 33610, 56 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/33610.pdf 57 * 58 * The 17 specification is in fact Intel Mobile Voltage Positioning - 59 * (IMVP-II). You can find more information in the datasheet of Max1718 60 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452 61 * 62 * The 13 specification corresponds to the Intel Pentium M series. There 63 * doesn't seem to be any named specification for these. The conversion 64 * tables are detailed directly in the various Pentium M datasheets: 65 * http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm 66 * 67 * The 14 specification corresponds to Intel Core series. There 68 * doesn't seem to be any named specification for these. The conversion 69 * tables are detailed directly in the various Pentium Core datasheets: 70 * http://www.intel.com/design/mobile/datashts/309221.htm 71 * 72 * The 110 (VRM 11) specification corresponds to Intel Conroe based series. 73 * http://www.intel.com/design/processor/applnots/313214.htm 74 */ 75 76 /* 77 * vrm is the VRM/VRD document version multiplied by 10. 78 * val is the 4-bit or more VID code. 79 * Returned value is in mV to avoid floating point in the kernel. 80 * Some VID have some bits in uV scale, this is rounded to mV. 81 */ 82 int vid_from_reg(int val, u8 vrm) 83 { 84 int vid; 85 86 switch (vrm) { 87 88 case 100: /* VRD 10.0 */ 89 /* compute in uV, round to mV */ 90 val &= 0x3f; 91 if ((val & 0x1f) == 0x1f) 92 return 0; 93 if ((val & 0x1f) <= 0x09 || val == 0x0a) 94 vid = 1087500 - (val & 0x1f) * 25000; 95 else 96 vid = 1862500 - (val & 0x1f) * 25000; 97 if (val & 0x20) 98 vid -= 12500; 99 return (vid + 500) / 1000; 100 101 case 110: /* Intel Conroe */ 102 /* compute in uV, round to mV */ 103 val &= 0xff; 104 if (val < 0x02 || val > 0xb2) 105 return 0; 106 return (1600000 - (val - 2) * 6250 + 500) / 1000; 107 108 case 24: /* Athlon64 & Opteron */ 109 val &= 0x1f; 110 if (val == 0x1f) 111 return 0; 112 /* fall through */ 113 case 25: /* AMD NPT 0Fh */ 114 val &= 0x3f; 115 return (val < 32) ? 1550 - 25 * val 116 : 775 - (25 * (val - 31)) / 2; 117 118 case 26: /* AMD family 10h to 15h, serial VID */ 119 val &= 0x7f; 120 if (val >= 0x7c) 121 return 0; 122 return DIV_ROUND_CLOSEST(15500 - 125 * val, 10); 123 124 case 91: /* VRM 9.1 */ 125 case 90: /* VRM 9.0 */ 126 val &= 0x1f; 127 return val == 0x1f ? 0 : 128 1850 - val * 25; 129 130 case 85: /* VRM 8.5 */ 131 val &= 0x1f; 132 return (val & 0x10 ? 25 : 0) + 133 ((val & 0x0f) > 0x04 ? 2050 : 1250) - 134 ((val & 0x0f) * 50); 135 136 case 84: /* VRM 8.4 */ 137 val &= 0x0f; 138 /* fall through */ 139 case 82: /* VRM 8.2 */ 140 val &= 0x1f; 141 return val == 0x1f ? 0 : 142 val & 0x10 ? 5100 - (val) * 100 : 143 2050 - (val) * 50; 144 case 17: /* Intel IMVP-II */ 145 val &= 0x1f; 146 return val & 0x10 ? 975 - (val & 0xF) * 25 : 147 1750 - val * 50; 148 case 13: 149 case 131: 150 val &= 0x3f; 151 /* Exception for Eden ULV 500 MHz */ 152 if (vrm == 131 && val == 0x3f) 153 val++; 154 return 1708 - val * 16; 155 case 14: /* Intel Core */ 156 /* compute in uV, round to mV */ 157 val &= 0x7f; 158 return val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000; 159 default: /* report 0 for unknown */ 160 if (vrm) 161 pr_warn("Requested unsupported VRM version (%u)\n", 162 (unsigned int)vrm); 163 return 0; 164 } 165 } 166 EXPORT_SYMBOL(vid_from_reg); 167 168 /* 169 * After this point is the code to automatically determine which 170 * VRM/VRD specification should be used depending on the CPU. 171 */ 172 173 struct vrm_model { 174 u8 vendor; 175 u8 family; 176 u8 model_from; 177 u8 model_to; 178 u8 stepping_to; 179 u8 vrm_type; 180 }; 181 182 #define ANY 0xFF 183 184 #ifdef CONFIG_X86 185 186 /* 187 * The stepping_to parameter is highest acceptable stepping for current line. 188 * The model match must be exact for 4-bit values. For model values 0x10 189 * and above (extended model), all models below the parameter will match. 190 */ 191 192 static struct vrm_model vrm_models[] = { 193 {X86_VENDOR_AMD, 0x6, 0x0, ANY, ANY, 90}, /* Athlon Duron etc */ 194 {X86_VENDOR_AMD, 0xF, 0x0, 0x3F, ANY, 24}, /* Athlon 64, Opteron */ 195 /* 196 * In theory, all NPT family 0Fh processors have 6 VID pins and should 197 * thus use vrm 25, however in practice not all mainboards route the 198 * 6th VID pin because it is never needed. So we use the 5 VID pin 199 * variant (vrm 24) for the models which exist today. 200 */ 201 {X86_VENDOR_AMD, 0xF, 0x40, 0x7F, ANY, 24}, /* NPT family 0Fh */ 202 {X86_VENDOR_AMD, 0xF, 0x80, ANY, ANY, 25}, /* future fam. 0Fh */ 203 {X86_VENDOR_AMD, 0x10, 0x0, ANY, ANY, 25}, /* NPT family 10h */ 204 {X86_VENDOR_AMD, 0x11, 0x0, ANY, ANY, 26}, /* family 11h */ 205 {X86_VENDOR_AMD, 0x12, 0x0, ANY, ANY, 26}, /* family 12h */ 206 {X86_VENDOR_AMD, 0x14, 0x0, ANY, ANY, 26}, /* family 14h */ 207 {X86_VENDOR_AMD, 0x15, 0x0, ANY, ANY, 26}, /* family 15h */ 208 209 {X86_VENDOR_INTEL, 0x6, 0x0, 0x6, ANY, 82}, /* Pentium Pro, 210 * Pentium II, Xeon, 211 * Mobile Pentium, 212 * Celeron */ 213 {X86_VENDOR_INTEL, 0x6, 0x7, 0x7, ANY, 84}, /* Pentium III, Xeon */ 214 {X86_VENDOR_INTEL, 0x6, 0x8, 0x8, ANY, 82}, /* Pentium III, Xeon */ 215 {X86_VENDOR_INTEL, 0x6, 0x9, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 216 {X86_VENDOR_INTEL, 0x6, 0xA, 0xA, ANY, 82}, /* Pentium III Xeon */ 217 {X86_VENDOR_INTEL, 0x6, 0xB, 0xB, ANY, 85}, /* Tualatin */ 218 {X86_VENDOR_INTEL, 0x6, 0xD, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 219 {X86_VENDOR_INTEL, 0x6, 0xE, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 220 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, ANY, 110}, /* Intel Conroe and 221 * later */ 222 {X86_VENDOR_INTEL, 0xF, 0x0, 0x0, ANY, 90}, /* P4 */ 223 {X86_VENDOR_INTEL, 0xF, 0x1, 0x1, ANY, 90}, /* P4 Willamette */ 224 {X86_VENDOR_INTEL, 0xF, 0x2, 0x2, ANY, 90}, /* P4 Northwood */ 225 {X86_VENDOR_INTEL, 0xF, 0x3, ANY, ANY, 100}, /* Prescott and above 226 * assume VRD 10 */ 227 228 {X86_VENDOR_CENTAUR, 0x6, 0x7, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 229 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x8, 0x7, 85}, /* Ezra T */ 230 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, 0x7, 85}, /* Nehemiah */ 231 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, ANY, 17}, /* C3-M, Eden-N */ 232 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, 0x7, 0}, /* No information */ 233 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, ANY, 13}, /* C7-M, C7, 234 * Eden (Esther) */ 235 {X86_VENDOR_CENTAUR, 0x6, 0xD, 0xD, ANY, 134}, /* C7-D, C7-M, C7, 236 * Eden (Esther) */ 237 }; 238 239 /* 240 * Special case for VIA model D: there are two different possible 241 * VID tables, so we have to figure out first, which one must be 242 * used. This resolves temporary drm value 134 to 14 (Intel Core 243 * 7-bit VID), 13 (Pentium M 6-bit VID) or 131 (Pentium M 6-bit VID 244 * + quirk for Eden ULV 500 MHz). 245 * Note: something similar might be needed for model A, I'm not sure. 246 */ 247 static u8 get_via_model_d_vrm(void) 248 { 249 unsigned int vid, brand, __maybe_unused dummy; 250 static const char *brands[4] = { 251 "C7-M", "C7", "Eden", "C7-D" 252 }; 253 254 rdmsr(0x198, dummy, vid); 255 vid &= 0xff; 256 257 rdmsr(0x1154, brand, dummy); 258 brand = ((brand >> 4) ^ (brand >> 2)) & 0x03; 259 260 if (vid > 0x3f) { 261 pr_info("Using %d-bit VID table for VIA %s CPU\n", 262 7, brands[brand]); 263 return 14; 264 } else { 265 pr_info("Using %d-bit VID table for VIA %s CPU\n", 266 6, brands[brand]); 267 /* Enable quirk for Eden */ 268 return brand == 2 ? 131 : 13; 269 } 270 } 271 272 static u8 find_vrm(u8 family, u8 model, u8 stepping, u8 vendor) 273 { 274 int i; 275 276 for (i = 0; i < ARRAY_SIZE(vrm_models); i++) { 277 if (vendor == vrm_models[i].vendor && 278 family == vrm_models[i].family && 279 model >= vrm_models[i].model_from && 280 model <= vrm_models[i].model_to && 281 stepping <= vrm_models[i].stepping_to) 282 return vrm_models[i].vrm_type; 283 } 284 285 return 0; 286 } 287 288 u8 vid_which_vrm(void) 289 { 290 struct cpuinfo_x86 *c = &cpu_data(0); 291 u8 vrm_ret; 292 293 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 294 return 0; /* doesn't have VID */ 295 296 vrm_ret = find_vrm(c->x86, c->x86_model, c->x86_mask, c->x86_vendor); 297 if (vrm_ret == 134) 298 vrm_ret = get_via_model_d_vrm(); 299 if (vrm_ret == 0) 300 pr_info("Unknown VRM version of your x86 CPU\n"); 301 return vrm_ret; 302 } 303 304 /* and now for something completely different for the non-x86 world */ 305 #else 306 u8 vid_which_vrm(void) 307 { 308 pr_info("Unknown VRM version of your CPU\n"); 309 return 0; 310 } 311 #endif 312 EXPORT_SYMBOL(vid_which_vrm); 313 314 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); 315 316 MODULE_DESCRIPTION("hwmon-vid driver"); 317 MODULE_LICENSE("GPL"); 318