cyw43-driver

I'm wondering how deep the hack is... it seems sending a frame is just setting some registers and waiting for an interrupt. This suggests (though I'm not an expert!) that they are talking to another layer of firmware that does the actual stuff? Reminds me a bit of the Raspberry pico board which has the main RP2040 SoC but where the WiFi is a separate WiFi/BT module (CYW43xx) with its own Arm cores. Not even the external register interface to the WiFi module is documented publicly, but there is an open source driver (https://github.com/georgerobotics/cyw43-driver/tree/cf924bb0...) so one can infer the specification. However, this driver yet again talks to software running on Arm codes inside the module, the code for which is supplied as big firmware binary blobs by the manufacturer (the blobs are actually in the linked repo, defined insid

Well, you can already do extreme tinkering to the point that RPi can no longer guarantee it functioning properly :) IIRC it's just that the bootcode.bin file is provided by Broadcom, and not the RPi foundation, so they can't open source it because they don't have the license to do so (this isn't the only proprietary blob in the default Pi distribution, but most of the other ones have open source alternatives/aren't that necessary/are open source now that they use the RP1 chip instead of broadcom peripherals). There's similar, slightly more open arrangements, with the Pi Pico W, where they can't provide the firmware for the Wifi chip, but they can provide a library to interface with it, with the caveat that the license _only_ allows for that library to be used with the RP* family of microcontrollers [1] [1]: https://github.com/georgeroboti

It does! Sadly, the firmware for the CYW43439 is a binary blob provided in the form of C header files[1] -- even though it's free for commercial use[2] as long as it's used with a RP2040 like in the Pico W. [1] https://github.com/georgerobotics/cyw43-driver/tree/main/fir... [2] https://github.com/georgerobotics/cyw43-driver/blob/main/LIC...