rpi-3b-wifi

Raspberry Pi 3B (32 Bit) Bare Metal Wifi Driver

This is an attempt to write bare metal wifi driver for raspberry pi by following Plan9 code.

Build Process

• Get docker desktop for your host operating system
• Change directory to rpi-3b-wifi
• Invoke ./build.sh
• Find binary in current working directory.
• IMAGE directory has all the files which can be directly copied to sd card of PI to test this code.

Current Status : Wifi driver NOT WORKING

Development Plan

• Set up basic utilities like printf, timers, interrupt
• Use emmec controller to read sd card's contents
• Add sdhost driver to read sd card's content
• Remove EMMC dependency to read sd card
• Write basic SDIO driver for EMMC
• Use emmc + sdio to enable wifi
• Get broadcom binary driver for wifi chip
• Load broadcom driver into wifi chip
• Join network with no security
• Join network with wpa2/psk security
• Initialize wifi
• Send packets
• Use light wight network library to use wifi
• Write basic http hello world test example using wifi

make DISABLE_EXP=1 to disable experimental

• Troubleshooting

Prefetch exception handler from dwelch67/mmu prints last value of R0 = 0000A1E0 DFSR= 000008A7 => [2:0] = 0b111 => translation fault page from manual. IFSR= 00001629 lr = 00008700 instruction = E92D4010 => e92d4010 push {r4, lr} 00008040

dump of data abort exception 00022680 00000001 00001629 00010584 E1D400B7 00022220 Last Ro value, DFSR, IFSR, LR, instruction, i don't know this

Last Ro value	DFSR	IFSR	LR	instruction	Unkwown
00022680	00000001	00001629	00010584	E1D400B7	00022220

Format source code using:

make format