[ericfontaine]

Ok, I simply linked to that as an example of a device that can interface with the free ath9k driver. Looking at https://www.qca.qualcomm.com/wp-content/uploads/2013/11/AR92... I can't really see any closer detail inside of the black boxes labeled "Baseband PHY and Wireless MAC" and "Host Interface" but I can make a very educated guess that they are running some very simple RISC and/or DSP with code off a ROM responsible for performing all the non-analog functions necessary for wireless media access control (e.g. error recovery, finding free channels, Rx/Tx buffering) and for interfacing with PCIe bus, outside of functions that handle higher level of the networking stack that are more practically implemented in the ath9k driver code running in the x86 cpu.