xref: /OK3568_Linux_fs/kernel/Documentation/hwmon/ibmaem.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunKernel driver ibmaem
2*4882a593Smuzhiyun====================
3*4882a593Smuzhiyun
4*4882a593SmuzhiyunThis driver talks to the IBM Systems Director Active Energy Manager, known
5*4882a593Smuzhiyunhenceforth as AEM.
6*4882a593Smuzhiyun
7*4882a593SmuzhiyunSupported systems:
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun  * Any recent IBM System X server with AEM support.
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun    This includes the x3350, x3550, x3650, x3655, x3755, x3850 M2,
12*4882a593Smuzhiyun    x3950 M2, and certain HC10/HS2x/LS2x/QS2x blades.
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun    The IPMI host interface
15*4882a593Smuzhiyun    driver ("ipmi-si") needs to be loaded for this driver to do anything.
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun    Prefix: 'ibmaem'
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun    Datasheet: Not available
20*4882a593Smuzhiyun
21*4882a593SmuzhiyunAuthor: Darrick J. Wong
22*4882a593Smuzhiyun
23*4882a593SmuzhiyunDescription
24*4882a593Smuzhiyun-----------
25*4882a593Smuzhiyun
26*4882a593SmuzhiyunThis driver implements sensor reading support for the energy and power meters
27*4882a593Smuzhiyunavailable on various IBM System X hardware through the BMC.  All sensor banks
28*4882a593Smuzhiyunwill be exported as platform devices; this driver can talk to both v1 and v2
29*4882a593Smuzhiyuninterfaces.  This driver is completely separate from the older ibmpex driver.
30*4882a593Smuzhiyun
31*4882a593SmuzhiyunThe v1 AEM interface has a simple set of features to monitor energy use.  There
32*4882a593Smuzhiyunis a register that displays an estimate of raw energy consumption since the
33*4882a593Smuzhiyunlast BMC reset, and a power sensor that returns average power use over a
34*4882a593Smuzhiyunconfigurable interval.
35*4882a593Smuzhiyun
36*4882a593SmuzhiyunThe v2 AEM interface is a bit more sophisticated, being able to present a wider
37*4882a593Smuzhiyunrange of energy and power use registers, the power cap as set by the AEM
38*4882a593Smuzhiyunsoftware, and temperature sensors.
39*4882a593Smuzhiyun
40*4882a593SmuzhiyunSpecial Features
41*4882a593Smuzhiyun----------------
42*4882a593Smuzhiyun
43*4882a593SmuzhiyunThe "power_cap" value displays the current system power cap, as set by the AEM
44*4882a593Smuzhiyunsoftware.  Setting the power cap from the host is not currently supported.
45