vfs: pass ppos=NULL to .read()/.write() of FMODE_STREAM files
[sfrench/cifs-2.6.git] / Documentation / hwmon / coretemp.rst
1 Kernel driver coretemp
2 ======================
3
4 Supported chips:
5   * All Intel Core family
6
7     Prefix: 'coretemp'
8
9     CPUID: family 0x6, models
10
11                             - 0xe (Pentium M DC), 0xf (Core 2 DC 65nm),
12                             - 0x16 (Core 2 SC 65nm), 0x17 (Penryn 45nm),
13                             - 0x1a (Nehalem), 0x1c (Atom), 0x1e (Lynnfield),
14                             - 0x26 (Tunnel Creek Atom), 0x27 (Medfield Atom),
15                             - 0x36 (Cedar Trail Atom)
16
17     Datasheet:
18
19                Intel 64 and IA-32 Architectures Software Developer's Manual
20                Volume 3A: System Programming Guide
21
22                http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
23
24 Author: Rudolf Marek
25
26 Description
27 -----------
28
29 This driver permits reading the DTS (Digital Temperature Sensor) embedded
30 inside Intel CPUs. This driver can read both the per-core and per-package
31 temperature using the appropriate sensors. The per-package sensor is new;
32 as of now, it is present only in the SandyBridge platform. The driver will
33 show the temperature of all cores inside a package under a single device
34 directory inside hwmon.
35
36 Temperature is measured in degrees Celsius and measurement resolution is
37 1 degree C. Valid temperatures are from 0 to TjMax degrees C, because
38 the actual value of temperature register is in fact a delta from TjMax.
39
40 Temperature known as TjMax is the maximum junction temperature of processor,
41 which depends on the CPU model. See table below. At this temperature, protection
42 mechanism will perform actions to forcibly cool down the processor. Alarm
43 may be raised, if the temperature grows enough (more than TjMax) to trigger
44 the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
45
46 All Sysfs entries are named with their core_id (represented here by 'X').
47
48 ================= ========================================================
49 tempX_input       Core temperature (in millidegrees Celsius).
50 tempX_max         All cooling devices should be turned on (on Core2).
51 tempX_crit        Maximum junction temperature (in millidegrees Celsius).
52 tempX_crit_alarm  Set when Out-of-spec bit is set, never clears.
53                   Correct CPU operation is no longer guaranteed.
54 tempX_label       Contains string "Core X", where X is processor
55                   number. For Package temp, this will be "Physical id Y",
56                   where Y is the package number.
57 ================= ========================================================
58
59 On CPU models which support it, TjMax is read from a model-specific register.
60 On other models, it is set to an arbitrary value based on weak heuristics.
61 If these heuristics don't work for you, you can pass the correct TjMax value
62 as a module parameter (tjmax).
63
64 Appendix A. Known TjMax lists (TBD):
65 Some information comes from ark.intel.com
66
67 =============== =============================================== ================
68 Process         Processor                                       TjMax(C)
69
70 22nm            Core i5/i7 Processors
71                 i7 3920XM, 3820QM, 3720QM, 3667U, 3520M         105
72                 i5 3427U, 3360M/3320M                           105
73                 i7 3770/3770K                                   105
74                 i5 3570/3570K, 3550, 3470/3450                  105
75                 i7 3770S                                        103
76                 i5 3570S/3550S, 3475S/3470S/3450S               103
77                 i7 3770T                                        94
78                 i5 3570T                                        94
79                 i5 3470T                                        91
80
81 32nm            Core i3/i5/i7 Processors
82                 i7 2600                                         98
83                 i7 660UM/640/620, 640LM/620, 620M, 610E         105
84                 i5 540UM/520/430, 540M/520/450/430              105
85                 i3 330E, 370M/350/330                           90 rPGA, 105 BGA
86                 i3 330UM                                        105
87
88 32nm            Core i7 Extreme Processors
89                 980X                                            100
90
91 32nm            Celeron Processors
92                 U3400                                           105
93                 P4505/P4500                                     90
94
95 32nm            Atom Processors
96                 S1260/1220                                      95
97                 S1240                                           102
98                 Z2460                                           90
99                 Z2760                                           90
100                 D2700/2550/2500                                 100
101                 N2850/2800/2650/2600                            100
102
103 45nm            Xeon Processors 5400 Quad-Core
104                 X5492, X5482, X5472, X5470, X5460, X5450        85
105                 E5472, E5462, E5450/40/30/20/10/05              85
106                 L5408                                           95
107                 L5430, L5420, L5410                             70
108
109 45nm            Xeon Processors 5200 Dual-Core
110                 X5282, X5272, X5270, X5260                      90
111                 E5240                                           90
112                 E5205, E5220                                    70, 90
113                 L5240                                           70
114                 L5238, L5215                                    95
115
116 45nm            Atom Processors
117                 D525/510/425/410                                100
118                 K525/510/425/410                                100
119                 Z670/650                                        90
120                 Z560/550/540/530P/530/520PT/520/515/510PT/510P  90
121                 Z510/500                                        90
122                 N570/550                                        100
123                 N475/470/455/450                                100
124                 N280/270                                        90
125                 330/230                                         125
126                 E680/660/640/620                                90
127                 E680T/660T/640T/620T                            110
128                 E665C/645C                                      90
129                 E665CT/645CT                                    110
130                 CE4170/4150/4110                                110
131                 CE4200 series                                   unknown
132                 CE5300 series                                   unknown
133
134 45nm            Core2 Processors
135                 Solo ULV SU3500/3300                            100
136                 T9900/9800/9600/9550/9500/9400/9300/8300/8100   105
137                 T6670/6500/6400                                 105
138                 T6600                                           90
139                 SU9600/9400/9300                                105
140                 SP9600/9400                                     105
141                 SL9600/9400/9380/9300                           105
142                 P9700/9600/9500/8800/8700/8600/8400/7570        105
143                 P7550/7450                                      90
144
145 45nm            Core2 Quad Processors
146                 Q9100/9000                                      100
147
148 45nm            Core2 Extreme Processors
149                 X9100/9000                                      105
150                 QX9300                                          100
151
152 45nm            Core i3/i5/i7 Processors
153                 i7 940XM/920                                    100
154                 i7 840QM/820/740/720                            100
155
156 45nm            Celeron Processors
157                 SU2300                                          100
158                 900                                             105
159
160 65nm            Core2 Duo Processors
161                 Solo U2200, U2100                               100
162                 U7700/7600/7500                                 100
163                 T7800/7700/7600/7500/7400/7300/7250/7200/7100   100
164                 T5870/5670/5600/5550/5500/5470/5450/5300/5270   100
165                 T5250                                           100
166                 T5800/5750/5200                                 85
167                 L7700/7500/7400/7300/7200                       100
168
169 65nm            Core2 Extreme Processors
170                 X7900/7800                                      100
171
172 65nm            Core Duo Processors
173                 U2500/2400                                      100
174                 T2700/2600/2450/2400/2350/2300E/2300/2250/2050  100
175                 L2500/2400/2300                                 100
176
177 65nm            Core Solo Processors
178                 U1500/1400/1300                                 100
179                 T1400/1350/1300/1250                            100
180
181 65nm            Xeon Processors 5000 Quad-Core
182                 X5000                                           90-95
183                 E5000                                           80
184                 L5000                                           70
185                 L5318                                           95
186
187 65nm            Xeon Processors 5000 Dual-Core
188                 5080, 5063, 5060, 5050, 5030                    80-90
189                 5160, 5150, 5148, 5140, 5130, 5120, 5110        80
190                 L5138                                           100
191
192 65nm            Celeron Processors
193                 T1700/1600                                      100
194                 560/550/540/530                                 100
195 =============== =============================================== ================