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 91: /* VRM 9.1 */ 119 case 90: /* VRM 9.0 */ 120 val &= 0x1f; 121 return val == 0x1f ? 0 : 122 1850 - val * 25; 123 124 case 85: /* VRM 8.5 */ 125 val &= 0x1f; 126 return (val & 0x10 ? 25 : 0) + 127 ((val & 0x0f) > 0x04 ? 2050 : 1250) - 128 ((val & 0x0f) * 50); 129 130 case 84: /* VRM 8.4 */ 131 val &= 0x0f; 132 /* fall through */ 133 case 82: /* VRM 8.2 */ 134 val &= 0x1f; 135 return val == 0x1f ? 0 : 136 val & 0x10 ? 5100 - (val) * 100 : 137 2050 - (val) * 50; 138 case 17: /* Intel IMVP-II */ 139 val &= 0x1f; 140 return val & 0x10 ? 975 - (val & 0xF) * 25 : 141 1750 - val * 50; 142 case 13: 143 case 131: 144 val &= 0x3f; 145 /* Exception for Eden ULV 500 MHz */ 146 if (vrm == 131 && val == 0x3f) 147 val++; 148 return 1708 - val * 16; 149 case 14: /* Intel Core */ 150 /* compute in uV, round to mV */ 151 val &= 0x7f; 152 return val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000; 153 default: /* report 0 for unknown */ 154 if (vrm) 155 pr_warn("Requested unsupported VRM version (%u)\n", 156 (unsigned int)vrm); 157 return 0; 158 } 159 } 160 EXPORT_SYMBOL(vid_from_reg); 161 162 /* 163 * After this point is the code to automatically determine which 164 * VRM/VRD specification should be used depending on the CPU. 165 */ 166 167 struct vrm_model { 168 u8 vendor; 169 u8 family; 170 u8 model_from; 171 u8 model_to; 172 u8 stepping_to; 173 u8 vrm_type; 174 }; 175 176 #define ANY 0xFF 177 178 #ifdef CONFIG_X86 179 180 /* 181 * The stepping_to parameter is highest acceptable stepping for current line. 182 * The model match must be exact for 4-bit values. For model values 0x10 183 * and above (extended model), all models below the parameter will match. 184 */ 185 186 static struct vrm_model vrm_models[] = { 187 {X86_VENDOR_AMD, 0x6, 0x0, ANY, ANY, 90}, /* Athlon Duron etc */ 188 {X86_VENDOR_AMD, 0xF, 0x0, 0x3F, ANY, 24}, /* Athlon 64, Opteron */ 189 /* 190 * In theory, all NPT family 0Fh processors have 6 VID pins and should 191 * thus use vrm 25, however in practice not all mainboards route the 192 * 6th VID pin because it is never needed. So we use the 5 VID pin 193 * variant (vrm 24) for the models which exist today. 194 */ 195 {X86_VENDOR_AMD, 0xF, 0x40, 0x7F, ANY, 24}, /* NPT family 0Fh */ 196 {X86_VENDOR_AMD, 0xF, 0x80, ANY, ANY, 25}, /* future fam. 0Fh */ 197 {X86_VENDOR_AMD, 0x10, 0x0, ANY, ANY, 25}, /* NPT family 10h */ 198 199 {X86_VENDOR_INTEL, 0x6, 0x0, 0x6, ANY, 82}, /* Pentium Pro, 200 * Pentium II, Xeon, 201 * Mobile Pentium, 202 * Celeron */ 203 {X86_VENDOR_INTEL, 0x6, 0x7, 0x7, ANY, 84}, /* Pentium III, Xeon */ 204 {X86_VENDOR_INTEL, 0x6, 0x8, 0x8, ANY, 82}, /* Pentium III, Xeon */ 205 {X86_VENDOR_INTEL, 0x6, 0x9, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 206 {X86_VENDOR_INTEL, 0x6, 0xA, 0xA, ANY, 82}, /* Pentium III Xeon */ 207 {X86_VENDOR_INTEL, 0x6, 0xB, 0xB, ANY, 85}, /* Tualatin */ 208 {X86_VENDOR_INTEL, 0x6, 0xD, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 209 {X86_VENDOR_INTEL, 0x6, 0xE, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 210 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, ANY, 110}, /* Intel Conroe and 211 * later */ 212 {X86_VENDOR_INTEL, 0xF, 0x0, 0x0, ANY, 90}, /* P4 */ 213 {X86_VENDOR_INTEL, 0xF, 0x1, 0x1, ANY, 90}, /* P4 Willamette */ 214 {X86_VENDOR_INTEL, 0xF, 0x2, 0x2, ANY, 90}, /* P4 Northwood */ 215 {X86_VENDOR_INTEL, 0xF, 0x3, ANY, ANY, 100}, /* Prescott and above 216 * assume VRD 10 */ 217 218 {X86_VENDOR_CENTAUR, 0x6, 0x7, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 219 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x8, 0x7, 85}, /* Ezra T */ 220 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, 0x7, 85}, /* Nehemiah */ 221 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, ANY, 17}, /* C3-M, Eden-N */ 222 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, 0x7, 0}, /* No information */ 223 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, ANY, 13}, /* C7-M, C7, 224 * Eden (Esther) */ 225 {X86_VENDOR_CENTAUR, 0x6, 0xD, 0xD, ANY, 134}, /* C7-D, C7-M, C7, 226 * Eden (Esther) */ 227 }; 228 229 /* 230 * Special case for VIA model D: there are two different possible 231 * VID tables, so we have to figure out first, which one must be 232 * used. This resolves temporary drm value 134 to 14 (Intel Core 233 * 7-bit VID), 13 (Pentium M 6-bit VID) or 131 (Pentium M 6-bit VID 234 * + quirk for Eden ULV 500 MHz). 235 * Note: something similar might be needed for model A, I'm not sure. 236 */ 237 static u8 get_via_model_d_vrm(void) 238 { 239 unsigned int vid, brand, dummy; 240 static const char *brands[4] = { 241 "C7-M", "C7", "Eden", "C7-D" 242 }; 243 244 rdmsr(0x198, dummy, vid); 245 vid &= 0xff; 246 247 rdmsr(0x1154, brand, dummy); 248 brand = ((brand >> 4) ^ (brand >> 2)) & 0x03; 249 250 if (vid > 0x3f) { 251 pr_info("Using %d-bit VID table for VIA %s CPU\n", 252 7, brands[brand]); 253 return 14; 254 } else { 255 pr_info("Using %d-bit VID table for VIA %s CPU\n", 256 6, brands[brand]); 257 /* Enable quirk for Eden */ 258 return brand == 2 ? 131 : 13; 259 } 260 } 261 262 static u8 find_vrm(u8 family, u8 model, u8 stepping, u8 vendor) 263 { 264 int i; 265 266 for (i = 0; i < ARRAY_SIZE(vrm_models); i++) { 267 if (vendor == vrm_models[i].vendor && 268 family == vrm_models[i].family && 269 model >= vrm_models[i].model_from && 270 model <= vrm_models[i].model_to && 271 stepping <= vrm_models[i].stepping_to) 272 return vrm_models[i].vrm_type; 273 } 274 275 return 0; 276 } 277 278 u8 vid_which_vrm(void) 279 { 280 struct cpuinfo_x86 *c = &cpu_data(0); 281 u8 vrm_ret; 282 283 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 284 return 0; /* doesn't have VID */ 285 286 vrm_ret = find_vrm(c->x86, c->x86_model, c->x86_mask, c->x86_vendor); 287 if (vrm_ret == 134) 288 vrm_ret = get_via_model_d_vrm(); 289 if (vrm_ret == 0) 290 pr_info("Unknown VRM version of your x86 CPU\n"); 291 return vrm_ret; 292 } 293 294 /* and now for something completely different for the non-x86 world */ 295 #else 296 u8 vid_which_vrm(void) 297 { 298 pr_info("Unknown VRM version of your CPU\n"); 299 return 0; 300 } 301 #endif 302 EXPORT_SYMBOL(vid_which_vrm); 303 304 MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); 305 306 MODULE_DESCRIPTION("hwmon-vid driver"); 307 MODULE_LICENSE("GPL"); 308