1185377Ssam// SPDX-License-Identifier: GPL-2.0-or-later 2185377Ssam/* 3185377Ssam * hwmon-vid.c - VID/VRM/VRD voltage conversions 4185377Ssam * 5185377Ssam * Copyright (c) 2004 Rudolf Marek <r.marek@assembler.cz> 6185377Ssam * 7185377Ssam * Partly imported from i2c-vid.h of the lm_sensors project 8185377Ssam * Copyright (c) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com> 9185377Ssam * With assistance from Trent Piepho <xyzzy@speakeasy.org> 10185377Ssam */ 11185377Ssam 12185377Ssam#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13185377Ssam 14185377Ssam#include <linux/module.h> 15185377Ssam#include <linux/kernel.h> 16185377Ssam#include <linux/hwmon-vid.h> 17204644Srpaulo 18185377Ssam/* 19185377Ssam * Common code for decoding VID pins. 20185377Ssam * 21185377Ssam * References: 22185377Ssam * 23185377Ssam * For VRM 8.4 to 9.1, "VRM x.y DC-DC Converter Design Guidelines", 24185377Ssam * available at http://developer.intel.com/. 25185377Ssam * 26185377Ssam * For VRD 10.0 and up, "VRD x.y Design Guide", 27185377Ssam * available at http://developer.intel.com/. 28185377Ssam * 29185377Ssam * AMD Athlon 64 and AMD Opteron Processors, AMD Publication 26094, 30185377Ssam * http://support.amd.com/us/Processor_TechDocs/26094.PDF 31185377Ssam * Table 74. VID Code Voltages 32185377Ssam * This corresponds to an arbitrary VRM code of 24 in the functions below. 33185377Ssam * These CPU models (K8 revision <= E) have 5 VID pins. See also: 34185377Ssam * Revision Guide for AMD Athlon 64 and AMD Opteron Processors, AMD Publication 25759, 35185377Ssam * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25759.pdf 36185377Ssam * 37185377Ssam * AMD NPT Family 0Fh Processors, AMD Publication 32559, 38185377Ssam * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/32559.pdf 39185377Ssam * Table 71. VID Code Voltages 40185377Ssam * This corresponds to an arbitrary VRM code of 25 in the functions below. 41185377Ssam * These CPU models (K8 revision >= F) have 6 VID pins. See also: 42185377Ssam * Revision Guide for AMD NPT Family 0Fh Processors, AMD Publication 33610, 43185377Ssam * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/33610.pdf 44185377Ssam * 45185377Ssam * The 17 specification is in fact Intel Mobile Voltage Positioning - 46185377Ssam * (IMVP-II). You can find more information in the datasheet of Max1718 47185377Ssam * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452 48185377Ssam * 49185377Ssam * The 13 specification corresponds to the Intel Pentium M series. There 50185377Ssam * doesn't seem to be any named specification for these. The conversion 51185377Ssam * tables are detailed directly in the various Pentium M datasheets: 52185377Ssam * https://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm 53185377Ssam * 54185377Ssam * The 14 specification corresponds to Intel Core series. There 55185377Ssam * doesn't seem to be any named specification for these. The conversion 56185377Ssam * tables are detailed directly in the various Pentium Core datasheets: 57185377Ssam * https://www.intel.com/design/mobile/datashts/309221.htm 58185377Ssam * 59185377Ssam * The 110 (VRM 11) specification corresponds to Intel Conroe based series. 60185377Ssam * https://www.intel.com/design/processor/applnots/313214.htm 61185377Ssam */ 62185377Ssam 63185377Ssam/* 64185377Ssam * vrm is the VRM/VRD document version multiplied by 10. 65185377Ssam * val is the 4-bit or more VID code. 66185377Ssam * Returned value is in mV to avoid floating point in the kernel. 67185377Ssam * Some VID have some bits in uV scale, this is rounded to mV. 68185377Ssam */ 69185377Ssamint vid_from_reg(int val, u8 vrm) 70185377Ssam{ 71185377Ssam int vid; 72185377Ssam 73185377Ssam switch (vrm) { 74185377Ssam 75185377Ssam case 100: /* VRD 10.0 */ 76185377Ssam /* compute in uV, round to mV */ 77185377Ssam val &= 0x3f; 78185377Ssam if ((val & 0x1f) == 0x1f) 79185377Ssam return 0; 80185377Ssam if ((val & 0x1f) <= 0x09 || val == 0x0a) 81185377Ssam vid = 1087500 - (val & 0x1f) * 25000; 82185377Ssam else 83185377Ssam vid = 1862500 - (val & 0x1f) * 25000; 84185377Ssam if (val & 0x20) 85185377Ssam vid -= 12500; 86185377Ssam return (vid + 500) / 1000; 87185377Ssam 88185377Ssam case 110: /* Intel Conroe */ 89185377Ssam /* compute in uV, round to mV */ 90185377Ssam val &= 0xff; 91185377Ssam if (val < 0x02 || val > 0xb2) 92185377Ssam return 0; 93185377Ssam return (1600000 - (val - 2) * 6250 + 500) / 1000; 94185377Ssam 95185377Ssam case 24: /* Athlon64 & Opteron */ 96185377Ssam val &= 0x1f; 97185377Ssam if (val == 0x1f) 98185377Ssam return 0; 99185377Ssam fallthrough; 100185377Ssam case 25: /* AMD NPT 0Fh */ 101185377Ssam val &= 0x3f; 102185377Ssam return (val < 32) ? 1550 - 25 * val 103185377Ssam : 775 - (25 * (val - 31)) / 2; 104185377Ssam 105185377Ssam case 26: /* AMD family 10h to 15h, serial VID */ 106185377Ssam val &= 0x7f; 107185377Ssam if (val >= 0x7c) 108185377Ssam return 0; 109185377Ssam return DIV_ROUND_CLOSEST(15500 - 125 * val, 10); 110185377Ssam 111185377Ssam case 91: /* VRM 9.1 */ 112185377Ssam case 90: /* VRM 9.0 */ 113185377Ssam val &= 0x1f; 114185377Ssam return val == 0x1f ? 0 : 115185377Ssam 1850 - val * 25; 116185377Ssam 117185377Ssam case 85: /* VRM 8.5 */ 118185377Ssam val &= 0x1f; 119185377Ssam return (val & 0x10 ? 25 : 0) + 120185377Ssam ((val & 0x0f) > 0x04 ? 2050 : 1250) - 121185377Ssam ((val & 0x0f) * 50); 122185377Ssam 123185377Ssam case 84: /* VRM 8.4 */ 124185377Ssam val &= 0x0f; 125185377Ssam fallthrough; 126185377Ssam case 82: /* VRM 8.2 */ 127185377Ssam val &= 0x1f; 128185377Ssam return val == 0x1f ? 0 : 129185377Ssam val & 0x10 ? 5100 - (val) * 100 : 130185377Ssam 2050 - (val) * 50; 131185377Ssam case 17: /* Intel IMVP-II */ 132185377Ssam val &= 0x1f; 133185377Ssam return val & 0x10 ? 975 - (val & 0xF) * 25 : 134185377Ssam 1750 - val * 50; 135185377Ssam case 13: 136185377Ssam case 131: 137185377Ssam val &= 0x3f; 138185377Ssam /* Exception for Eden ULV 500 MHz */ 139185377Ssam if (vrm == 131 && val == 0x3f) 140185377Ssam val++; 141185377Ssam return 1708 - val * 16; 142185377Ssam case 14: /* Intel Core */ 143185377Ssam /* compute in uV, round to mV */ 144185377Ssam val &= 0x7f; 145185377Ssam return val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000; 146185377Ssam default: /* report 0 for unknown */ 147185377Ssam if (vrm) 148185377Ssam pr_warn("Requested unsupported VRM version (%u)\n", 149185377Ssam (unsigned int)vrm); 150185377Ssam return 0; 151185377Ssam } 152185377Ssam} 153185377SsamEXPORT_SYMBOL(vid_from_reg); 154185377Ssam 155185377Ssam/* 156185377Ssam * After this point is the code to automatically determine which 157185377Ssam * VRM/VRD specification should be used depending on the CPU. 158185377Ssam */ 159185377Ssam 160185377Ssamstruct vrm_model { 161185377Ssam u8 vendor; 162185377Ssam u8 family; 163185377Ssam u8 model_from; 164185377Ssam u8 model_to; 165185377Ssam u8 stepping_to; 166185377Ssam u8 vrm_type; 167185377Ssam}; 168185377Ssam 169185377Ssam#define ANY 0xFF 170185377Ssam 171185377Ssam#ifdef CONFIG_X86 172185377Ssam 173185377Ssam/* 174185377Ssam * The stepping_to parameter is highest acceptable stepping for current line. 175185377Ssam * The model match must be exact for 4-bit values. For model values 0x10 176185377Ssam * and above (extended model), all models below the parameter will match. 177185377Ssam */ 178185377Ssam 179static struct vrm_model vrm_models[] = { 180 {X86_VENDOR_AMD, 0x6, 0x0, ANY, ANY, 90}, /* Athlon Duron etc */ 181 {X86_VENDOR_AMD, 0xF, 0x0, 0x3F, ANY, 24}, /* Athlon 64, Opteron */ 182 /* 183 * In theory, all NPT family 0Fh processors have 6 VID pins and should 184 * thus use vrm 25, however in practice not all mainboards route the 185 * 6th VID pin because it is never needed. So we use the 5 VID pin 186 * variant (vrm 24) for the models which exist today. 187 */ 188 {X86_VENDOR_AMD, 0xF, 0x40, 0x7F, ANY, 24}, /* NPT family 0Fh */ 189 {X86_VENDOR_AMD, 0xF, 0x80, ANY, ANY, 25}, /* future fam. 0Fh */ 190 {X86_VENDOR_AMD, 0x10, 0x0, ANY, ANY, 25}, /* NPT family 10h */ 191 {X86_VENDOR_AMD, 0x11, 0x0, ANY, ANY, 26}, /* family 11h */ 192 {X86_VENDOR_AMD, 0x12, 0x0, ANY, ANY, 26}, /* family 12h */ 193 {X86_VENDOR_AMD, 0x14, 0x0, ANY, ANY, 26}, /* family 14h */ 194 {X86_VENDOR_AMD, 0x15, 0x0, ANY, ANY, 26}, /* family 15h */ 195 196 {X86_VENDOR_INTEL, 0x6, 0x0, 0x6, ANY, 82}, /* Pentium Pro, 197 * Pentium II, Xeon, 198 * Mobile Pentium, 199 * Celeron */ 200 {X86_VENDOR_INTEL, 0x6, 0x7, 0x7, ANY, 84}, /* Pentium III, Xeon */ 201 {X86_VENDOR_INTEL, 0x6, 0x8, 0x8, ANY, 82}, /* Pentium III, Xeon */ 202 {X86_VENDOR_INTEL, 0x6, 0x9, 0x9, ANY, 13}, /* Pentium M (130 nm) */ 203 {X86_VENDOR_INTEL, 0x6, 0xA, 0xA, ANY, 82}, /* Pentium III Xeon */ 204 {X86_VENDOR_INTEL, 0x6, 0xB, 0xB, ANY, 85}, /* Tualatin */ 205 {X86_VENDOR_INTEL, 0x6, 0xD, 0xD, ANY, 13}, /* Pentium M (90 nm) */ 206 {X86_VENDOR_INTEL, 0x6, 0xE, 0xE, ANY, 14}, /* Intel Core (65 nm) */ 207 {X86_VENDOR_INTEL, 0x6, 0xF, ANY, ANY, 110}, /* Intel Conroe and 208 * later */ 209 {X86_VENDOR_INTEL, 0xF, 0x0, 0x0, ANY, 90}, /* P4 */ 210 {X86_VENDOR_INTEL, 0xF, 0x1, 0x1, ANY, 90}, /* P4 Willamette */ 211 {X86_VENDOR_INTEL, 0xF, 0x2, 0x2, ANY, 90}, /* P4 Northwood */ 212 {X86_VENDOR_INTEL, 0xF, 0x3, ANY, ANY, 100}, /* Prescott and above 213 * assume VRD 10 */ 214 215 {X86_VENDOR_CENTAUR, 0x6, 0x7, 0x7, ANY, 85}, /* Eden ESP/Ezra */ 216 {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x8, 0x7, 85}, /* Ezra T */ 217 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, 0x7, 85}, /* Nehemiah */ 218 {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, ANY, 17}, /* C3-M, Eden-N */ 219 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, 0x7, 0}, /* No information */ 220 {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, ANY, 13}, /* C7-M, C7, 221 * Eden (Esther) */ 222 {X86_VENDOR_CENTAUR, 0x6, 0xD, 0xD, ANY, 134}, /* C7-D, C7-M, C7, 223 * Eden (Esther) */ 224}; 225 226/* 227 * Special case for VIA model D: there are two different possible 228 * VID tables, so we have to figure out first, which one must be 229 * used. This resolves temporary drm value 134 to 14 (Intel Core 230 * 7-bit VID), 13 (Pentium M 6-bit VID) or 131 (Pentium M 6-bit VID 231 * + quirk for Eden ULV 500 MHz). 232 * Note: something similar might be needed for model A, I'm not sure. 233 */ 234static u8 get_via_model_d_vrm(void) 235{ 236 unsigned int vid, brand, __maybe_unused dummy; 237 static const char *brands[4] = { 238 "C7-M", "C7", "Eden", "C7-D" 239 }; 240 241 rdmsr(0x198, dummy, vid); 242 vid &= 0xff; 243 244 rdmsr(0x1154, brand, dummy); 245 brand = ((brand >> 4) ^ (brand >> 2)) & 0x03; 246 247 if (vid > 0x3f) { 248 pr_info("Using %d-bit VID table for VIA %s CPU\n", 249 7, brands[brand]); 250 return 14; 251 } else { 252 pr_info("Using %d-bit VID table for VIA %s CPU\n", 253 6, brands[brand]); 254 /* Enable quirk for Eden */ 255 return brand == 2 ? 131 : 13; 256 } 257} 258 259static u8 find_vrm(u8 family, u8 model, u8 stepping, u8 vendor) 260{ 261 int i; 262 263 for (i = 0; i < ARRAY_SIZE(vrm_models); i++) { 264 if (vendor == vrm_models[i].vendor && 265 family == vrm_models[i].family && 266 model >= vrm_models[i].model_from && 267 model <= vrm_models[i].model_to && 268 stepping <= vrm_models[i].stepping_to) 269 return vrm_models[i].vrm_type; 270 } 271 272 return 0; 273} 274 275u8 vid_which_vrm(void) 276{ 277 struct cpuinfo_x86 *c = &cpu_data(0); 278 u8 vrm_ret; 279 280 if (c->x86 < 6) /* Any CPU with family lower than 6 */ 281 return 0; /* doesn't have VID */ 282 283 vrm_ret = find_vrm(c->x86, c->x86_model, c->x86_stepping, c->x86_vendor); 284 if (vrm_ret == 134) 285 vrm_ret = get_via_model_d_vrm(); 286 if (vrm_ret == 0) 287 pr_info("Unknown VRM version of your x86 CPU\n"); 288 return vrm_ret; 289} 290 291/* and now for something completely different for the non-x86 world */ 292#else 293u8 vid_which_vrm(void) 294{ 295 pr_info("Unknown VRM version of your CPU\n"); 296 return 0; 297} 298#endif 299EXPORT_SYMBOL(vid_which_vrm); 300 301MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>"); 302 303MODULE_DESCRIPTION("hwmon-vid driver"); 304MODULE_LICENSE("GPL"); 305