Blog/IT87 driver for the it8686 sensor chip
2021-11-05 How to enable the IT87 driver for the it8686 sensor chip[edit | edit source]
I have a Gigabyte B450M-DS3H motherboard and a AMD Ryzen 3000G CPU with it. The hardware monitoring support in Linux has long been lacking support for the ITE IT8686E Super IO Sensor chipset that this motherboard uses. This means that Linux has only had basic support for temperature monitoring, but no support for detailed temperatures and voltage monitoring.
The output from lm_sensors has been very brief with k10temp showing one CPU temperature and the ACPI module not being accurate.
/home/forza # sensors
amdgpu-pci-0700 Adapter: PCI adapter GPU temp: +26.0°C acpitz-acpi-0 Adapter: ACPI interface ACPI temp: +16.8°C (crit = +20.8°C) k10temp-pci-00c3 Adapter: PCI adapter CPU temp: +26.5°C
The modified it87 driver[edit | edit source]
I found a modified it87 driver that supports the IT8686 chipset over at Frank Crawford's fork of the it87 driver. Installation requires that you have kernel sources installed and that you have the gcc compiler toolchain installed. Please see your distribution's manual for how to do this.
Compiling the source code[edit | edit source]
1. Download the source code.
# mkdir /usr/src/it87 # cd /usr/src/it87 /usr/src/it87 # wget https://github.com/frankcrawford/it87/archive/refs/heads/master.zip
2. Unpack the source code.
/usr/src/it87 # unzip master.zip
Archive: master.zip 40bec4b5a7896d4406d2a7d095d06c0624c24aca creating: it87-master/ inflating: it87-master/ISSUES inflating: it87-master/ITE_Register_map.csv inflating: it87-master/ITE_Register_map.pdf inflating: it87-master/Makefile inflating: it87-master/README inflating: it87-master/compat.h inflating: it87-master/dkms.conf inflating: it87-master/it87.c
3. Compile the source code
/usr/src/it87 # cd it87-master
/usr/src/it87/it87-master # make
CC [M] /usr/src/it87/new/it87-master/it87.o
/usr/src/it87/new/it87-master/it87.c: In function ‘get_temp_type’:
/usr/src/it87/new/it87-master/it87.c:1479:28: warning: this statement may fall through [-Wimplicit-fallthrough=]
1479 | if (index < 3)
| ^
/usr/src/it87/new/it87-master/it87.c:1481:17: note: here
1481 | case it8655:
| ^~~~
MODPOST /usr/src/it87/new/it87-master/Module.symvers
CC [M] /usr/src/it87/new/it87-master/it87.mod.o
LD [M] /usr/src/it87/new/it87-master/it87.ko
4. Install the it87 module
/usr/src/it87/it87-master # sudo make install
5. Load the module. You have add force_id=0x8686 ignore_resource_conflict=1 to modprobe to load the module.
/usr/src/it87/it87-master # sudo modprobe it87 force_id=0x8686 ignore_resource_conflict=1
The kernel logs will show it successfully loaded:
# dmesg
[435404.633106] it87: loading out-of-tree module taints kernel. [435404.634328] it87: it87 driver version v1.0-48-g40bec4b [435404.634447] it87: Found IT8686E chip at 0xa40, revision 2 [435404.634494] it87: Beeping is supported [435404.634532] ACPI Warning: SystemIO range 0x0000000000000A45-0x0000000000000A46 conflicts with OpRegion 0x0000000000000A45-0x0000000000000A46 (\GSA1.SIO1) (20210604/utaddress-204) [435404.634543] ACPI: OSL: Resource conflict; ACPI support missing from driver? [435404.634544] ACPI: OSL: Resource conflict: System may be unstable or behave erratically
Creating a custom senors.d/it87.conf[edit | edit source]
The raw voltage and temperature values from the sensor chip needs adjusting to be correct. Different motherboard models need different calculations to show the correct values and names for each of the inputs. This is achieved by creating a file /etc/sensors.d/gigabyte-it87.conf with the following content:
File: /etc/sensors.d/gigabyte-it87.conf
chip "it8686-*"
label in0 "Vcore"
label in1 "+3.3V"
compute in1 @ * 1.65, @ / 1.65
label in2 "+12.0V"
compute in2 @ * 6, @ / 6
label in3 "+5.0V"
compute in3 @ * 2.5, @ / 2.5
label in4 "VSOC"
label in5 "VDDP"
label in6 "DRAM"
label in7 "3VSB"
label in8 "VBAT"
label fan1 "CPU Fan"
label fan2 "SYS Fan 1"
label fan3 "SYS Fan 2"
label fan4 "SYS Fan 3_PUMP"
label fan5 "CPU_OPT"
label temp1 "System"
label temp2 "Chipset"
label temp3 "CPU"
label temp4 "PCIe x16"
label temp5 "VRM"
label temp6 "VSoC"
label intrusion0 "Intrusion"
I based the above from a sensors.d config file for a similar Gigabyte motherboard, so the values might not be absolutely correct.
Now when you run sensors you get proper names and values for each input.
# sensors
it8686-isa-0a40 Adapter: ISA adapter Vcore: 732.00 mV (min = +0.00 V, max = +3.06 V) +3.3V: 3.43 V (min = +0.00 V, max = +5.05 V) +12.0V: 12.31 V (min = +0.00 V, max = +18.36 V) +5.0V: 4.98 V (min = +0.00 V, max = +7.65 V) VSOC: 1.10 V (min = +0.00 V, max = +3.06 V) VDDP: 912.00 mV (min = +0.00 V, max = +3.06 V) DRAM: 1.21 V (min = +0.00 V, max = +3.06 V) 3VSB: 3.29 V (min = +0.00 V, max = +6.12 V) VBAT: 3.26 V CPU Fan: 744 RPM (min = 0 RPM) SYS Fan 1: 0 RPM (min = 0 RPM) System: +32.0°C (low = +127.0°C, high = +127.0°C) sensor = thermistor Chipset: +51.0°C (low = +127.0°C, high = +127.0°C) sensor = thermistor CPU: +26.0°C (low = +0.0°C, high = +70.0°C) sensor = AMD AMDSI PCIe x16: +18.0°C (low = +0.0°C, high = +127.0°C) sensor = thermistor VRM: +30.0°C (low = +0.0°C, high = -113.0°C) sensor = thermistor VSoC: +37.0°C (low = +0.0°C, high = -113.0°C) sensor = thermistor
Loading it87 on Gentoo Linux[edit | edit source]
If you want to autoload the module on Gentoo Linux during the boot you can add the module config to either /etc/modules-load.d/it87.conf (systemd) or /etc/conf.d/modules (OpenRC). Then you must add the modprobe options to /etc/modprobe.d/it87.conf.
File: /etc/modprobe.d/it87.conf
options it87 force_id=0x8686 ignore_resource_conflict=1
For OpenRC you would use:
File: /etc/conf.d/modules
modules="it87"
For systemd you would use:
File: /etc/modules-load.d/it87.conf
it87
