Linux Gets New Thermal Driver Code Ahead of Alder Lake
Written by Michael Larabel in Intel on 4 July 2021 at 09:14 AM EDT. 1 Comment
INTEL --
The thermal subsystem updates for the Linux 5.14 kernel include more work on Intel's int340x driver that is used by newer Intel laptops for dealing with their varying thermal control capabilities and exposing more thermal information to user-space for use by Intel's Thermal Daemon (Thermald). This cycle the work includes a new driver that will be used by next-gen Alder Lake SoCs.

Among the Intel int340x thermal work for Linux 5.14 is the introduction of a new processor_thermal PCI MMIO-based driver. This PCI driver registers a thermal zone and the temperatures and trip points are using PCI MMIO rather than ACPI methods for communication. This PCI MMIO thermal driver is set so far just to be used for upcoming Alder Lake SoCs and isn't used by already supported int340x-using hardware.

Also for this next kernel the Intel int340x code exports more attributes via sysfs. The current DDR memory data rate is exposed as a new "ddr_data_rate" attribute on sysfs for those wondering if the DDR speed is being set lower for thermal reasons.

The other new attribute on sysfs for int340x is "rfi_restriction" for showing or setting the Radio Frequency Interference (RFI) protection state. This is part of Intel's recent work around radio frequency interference mitigation on Linux.

The Intel thermal work and other new code in this subsystem can be found via this pull request. The work though hasn't landed as it looks like the thermal code will be re-submitted but without the NVIDIA Tegra changes due to build breakage.
Related News
About The Author
Author picture

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter or contacted via MichaelLarabel.com.

Popular News This Week