I have seen references to this around for a while on different forums and such, mainly for the rpi. This module definitely affects the RPis, and possibly other arm SBCs and even my laptop, but I do not know. The linux kernel tree, apparently, has a driver from 2018 and in the meantime, broadcom sold this business to cypress. Cypress has continued to develop and updated firmware and driver info on their web page in June this year. I have hacked in the firmware on a B+ and 'it appears' to work better with iwd. I am trying to build the kernel module to see if it is any better.
What I have noticed is that with iwd, the current brcmfmac module has trouble reconnecting to its SSID if it goes down then comes back up. Also, iwd AP mode will not work at all with the current brcmfmac module. I have made a kernel patch and am now trying to get it to build.
Does anyone have any experience with this new module? Any notes of improved performance with even the firmware files?
Can anyone point to a page that details how to build the module without building the whole kernel?
I can be a guilea pig and report back on any improvements.
https://community.cypress.com/docs/DOC-20044
https://community.cypress.com/servlet/JiveServlet/download/20044-1-56065/cypress-fmac-v5.4.18-2020_0625.zip