xref: /linux/Documentation/hwmon/sbtsi_temp.rst (revision daa2be74b1b2302004945b2a5e32424e177cc7da)
1.. SPDX-License-Identifier: GPL-2.0-or-later
2
3Kernel driver sbtsi_temp
4========================
5
6Supported hardware:
7
8  * Sideband interface (SBI) Temperature Sensor Interface (SB-TSI)
9    compliant AMD SoC temperature device.
10
11    Prefix: 'sbtsi_temp'
12
13    Addresses scanned: This driver doesn't support address scanning.
14
15    To instantiate this driver on an AMD CPU with SB-TSI
16    support, the i2c bus number would be the bus connected from the board
17    management controller (BMC) to the CPU. The i2c address is specified in
18    Section 6.3.1 of the SoC register reference: The SB-TSI address is normally
19    98h for socket 0 and 90h for socket 1, but it could vary based on hardware
20    address select pins.
21
22    Datasheet: The SB-TSI interface and protocol is available as part of
23               the open source SoC register reference at:
24
25	       https://www.amd.com/system/files/TechDocs/56255_OSRR.pdf
26
27               The Advanced Platform Management Link (APML) Specification is
28               available at:
29
30	       http://developer.amd.com/wordpress/media/2012/10/41918.pdf
31
32Author: Kun Yi <kunyi@google.com>
33
34Description
35-----------
36
37The SBI temperature sensor interface (SB-TSI) is an emulation of the software
38and physical interface of a typical 8-pin remote temperature sensor (RTS) on
39AMD SoCs. It implements one temperature sensor with readings and limit
40registers encode the temperature in increments of 0.125 from 0 to 255.875.
41Limits can be set through the writable thresholds, and if reached will trigger
42corresponding alert signals.
43