Apple M1 PCIe Driver Under Review For The Linux Kernel
This Apple PCIe driver created by the open-source community -- including Correlium and Asahi Linux -- is for the M1 right now while presumably will be applicable to future iterations of the Apple Silicon SoCs. With this driver Linux can begin working for the Apple M1 device USB Type-A ports as well as the Ethernet port.
Work is still being done for getting the WiFi and Bluetooth working on these Apple Silicon devices that began shipping at the end of last year. While the Apple M1 PCIe driver is now out for review, it also depends upon a GPIO driver that is still a work-in-progress. So for now this driver was submitted as a "request for comments".
More details for those interested in this Linux work around Apple M1 PCI Express support can see this kernel mailing list.
For a look at the overall Apple M1 Linux state at the moment, see the Asahi project's August progress report from yesterday.