AMD Working On WiFi RFI Interference Mitigation For Linux

As a step toward further improving AMD laptop support under Linux, AMD engineers have been working on WiFi radio frequency interference (RFI) mitigation support for Linux with their latest laptops.

Similar to Intel RFI work years ago, AMD is trying to mitigate radio frequency interference between the WiFi chipset and other components with new AMD Ryzen laptops. In particular, working around interference from the GDDR/DDR memory clocks with the local radio module frequency bands used by WiFi 6 / 6e / 7 can cause problems. The mitigation is to advertise the frequencies in use and in turn consumers can use this information to avoid those frequencies for "sensitive" features.

This ACPI WBRF mitigation is currently wired up between the AMD Radeon graphics driver's power management code and then consuming that frequency information are patches to the Qualcomm Ath12k WiFi driver and the MT76 WiFi driver for the MediaTek MT7921 chipset. One suggestion raised already in the code review is potentially moving the ACPI WBRF handling into the mac80211/cfg80211 code rather than duplicating the logic in each of the relevant WiFi drivers being used.

On the AMD platform side this ACPI WBRF feature is currently implemented for SMU 13.0.0 and SMU 13.0.7 IP blocks that are found with the very newest AMD Ryzen laptop designs beginning to come to market.

Those interested in this wiFi radio frequency interference mitigation work being pursued by AMD can find this set of patches now out for review on the kernel mailing list.