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Linux kernel mirror (for testing)
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linux
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 NPT 0Fh (Athlon64 & Opteron), AMD Publication 32559,
41 * http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/32559.pdf
42 * Table 71. VID Code Voltages
43 * AMD Opteron processors don't follow the Intel specifications.
44 * I'm going to "make up" 2.4 as the spec number for the Opterons.
45 * No good reason just a mnemonic for the 24x Opteron processor
46 * series.
47 *
48 * The 17 specification is in fact Intel Mobile Voltage Positioning -
49 * (IMVP-II). You can find more information in the datasheet of Max1718
50 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452
51 *
52 * The 13 specification corresponds to the Intel Pentium M series. There
53 * doesn't seem to be any named specification for these. The conversion
54 * tables are detailed directly in the various Pentium M datasheets:
55 * http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm
56 *
57 * The 14 specification corresponds to Intel Core series. There
58 * doesn't seem to be any named specification for these. The conversion
59 * tables are detailed directly in the various Pentium Core datasheets:
60 * http://www.intel.com/design/mobile/datashts/309221.htm
61 *
62 * The 110 (VRM 11) specification corresponds to Intel Conroe based series.
63 * http://www.intel.com/design/processor/applnots/313214.htm
64 */
65
66/*
67 * vrm is the VRM/VRD document version multiplied by 10.
68 * val is the 4-bit or more VID code.
69 * Returned value is in mV to avoid floating point in the kernel.
70 * Some VID have some bits in uV scale, this is rounded to mV.
71 */
72int vid_from_reg(int val, u8 vrm)
73{
74 int vid;
75
76 switch(vrm) {
77
78 case 100: /* VRD 10.0 */
79 /* compute in uV, round to mV */
80 val &= 0x3f;
81 if((val & 0x1f) == 0x1f)
82 return 0;
83 if((val & 0x1f) <= 0x09 || val == 0x0a)
84 vid = 1087500 - (val & 0x1f) * 25000;
85 else
86 vid = 1862500 - (val & 0x1f) * 25000;
87 if(val & 0x20)
88 vid -= 12500;
89 return((vid + 500) / 1000);
90
91 case 110: /* Intel Conroe */
92 /* compute in uV, round to mV */
93 val &= 0xff;
94 if (val < 0x02 || val > 0xb2)
95 return 0;
96 return((1600000 - (val - 2) * 6250 + 500) / 1000);
97
98 case 24: /* AMD NPT 0Fh (Athlon64 & Opteron) */
99 val &= 0x3f;
100 return (val < 32) ? 1550 - 25 * val
101 : 775 - (25 * (val - 31)) / 2;
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
148struct 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
162static 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
184static 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
201u8 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
227u8 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
234EXPORT_SYMBOL(vid_from_reg);
235EXPORT_SYMBOL(vid_which_vrm);
236
237MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
238
239MODULE_DESCRIPTION("hwmon-vid driver");
240MODULE_LICENSE("GPL");