1 Kernel driver k8temp 1 Kernel driver k8temp
2 ==================== 2 ====================
3 3
4 Supported chips: 4 Supported chips:
5 5
6 * AMD Athlon64/FX or Opteron CPUs 6 * AMD Athlon64/FX or Opteron CPUs
7 7
8 Prefix: 'k8temp' 8 Prefix: 'k8temp'
9 9
10 Addresses scanned: PCI space 10 Addresses scanned: PCI space
11 11
12 Datasheet: https://www.amd.com/system/file 12 Datasheet: https://www.amd.com/system/files/TechDocs/32559.pdf
13 13
14 Author: Rudolf Marek 14 Author: Rudolf Marek
15 15
16 Contact: Rudolf Marek <r.marek@assembler.cz> 16 Contact: Rudolf Marek <r.marek@assembler.cz>
17 17
18 Description 18 Description
19 ----------- 19 -----------
20 20
21 This driver permits reading temperature sensor 21 This driver permits reading temperature sensor(s) embedded inside AMD K8
22 family CPUs (Athlon64/FX, Opteron). Official d 22 family CPUs (Athlon64/FX, Opteron). Official documentation says that it works
23 from revision F of K8 core, but in fact it see 23 from revision F of K8 core, but in fact it seems to be implemented for all
24 revisions of K8 except the first two revisions 24 revisions of K8 except the first two revisions (SH-B0 and SH-B3).
25 25
26 Please note that you will need at least lm-sen 26 Please note that you will need at least lm-sensors 2.10.1 for proper userspace
27 support. 27 support.
28 28
29 There can be up to four temperature sensors in 29 There can be up to four temperature sensors inside single CPU. The driver
30 will auto-detect the sensors and will display 30 will auto-detect the sensors and will display only temperatures from
31 implemented sensors. 31 implemented sensors.
32 32
33 Mapping of /sys files is as follows: 33 Mapping of /sys files is as follows:
34 34
35 ============= ================================ 35 ============= ===================================
36 temp1_input temperature of Core 0 and "place 36 temp1_input temperature of Core 0 and "place" 0
37 temp2_input temperature of Core 0 and "place 37 temp2_input temperature of Core 0 and "place" 1
38 temp3_input temperature of Core 1 and "place 38 temp3_input temperature of Core 1 and "place" 0
39 temp4_input temperature of Core 1 and "place 39 temp4_input temperature of Core 1 and "place" 1
40 ============= ================================ 40 ============= ===================================
41 41
42 Temperatures are measured in degrees Celsius a 42 Temperatures are measured in degrees Celsius and measurement resolution is
43 1 degree C. It is expected that future CPU wil 43 1 degree C. It is expected that future CPU will have better resolution. The
44 temperature is updated once a second. Valid te 44 temperature is updated once a second. Valid temperatures are from -49 to
45 206 degrees C. 45 206 degrees C.
46 46
47 Temperature known as TCaseMax was specified fo 47 Temperature known as TCaseMax was specified for processors up to revision E.
48 This temperature is defined as temperature bet 48 This temperature is defined as temperature between heat-spreader and CPU
49 case, so the internal CPU temperature supplied 49 case, so the internal CPU temperature supplied by this driver can be higher.
50 There is no easy way how to measure the temper 50 There is no easy way how to measure the temperature which will correlate
51 with TCaseMax temperature. 51 with TCaseMax temperature.
52 52
53 For newer revisions of CPU (rev F, socket AM2) 53 For newer revisions of CPU (rev F, socket AM2) there is a mathematically
54 computed temperature called TControl, which mu 54 computed temperature called TControl, which must be lower than TControlMax.
55 55
56 The relationship is following: 56 The relationship is following:
57 57
58 temp1_input - TjOffset*2 < TControlMax 58 temp1_input - TjOffset*2 < TControlMax,
59 59
60 TjOffset is not yet exported by the driver, TC 60 TjOffset is not yet exported by the driver, TControlMax is usually
61 70 degrees C. The rule of the thumb -> CPU tem 61 70 degrees C. The rule of the thumb -> CPU temperature should not cross
62 60 degrees C too much. 62 60 degrees C too much.
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