Everything is licensed under the GPLv2 or later unless stated otherwise

developing with this lk overlay:

[clever@system76:~/apps/rpi]$ git clone --recurse-submodules git@github.com:librerpi/lk-overlay.git
[clever@system76:~/apps/rpi]$ cd lk-overlay/
[clever@system76:~/apps/rpi/lk-overlay]$ nix-shell -A shell
[nix-shell:~/apps/rpi/lk-overlay]$ make PROJECT=rpi3-bootcode
[nix-shell:~/apps/rpi/lk-overlay]$ ls -lh build-rpi3-bootcode/lk.bin
-rwxr-xr-x 1 clever users 113K Mar 31 23:27 build-rpi3-bootcode/lk.bin

what features work

Feature	rpi1	rpi2	rpi3	rpi4
composite NTSC video	[x]	[x]	[x]	?
DSI video	[ ]	[ ]	[ ]	[ ]
HDMI video	[ ]	[ ]	[ ]	[ ]
DPI video, partially tested	[x]	[x]	[x]	?
v3d partially working	[x]	[x]	[x]	?
full 2d composition under firmware control	[x]	[x]	[x]	?
CSI, untested	[ ]	[ ]	[ ]	[ ]
i2c host (under linux)	?	[x]	[x]	?
SPI, untested	[ ]	[ ]	[ ]	[ ]
ISP, lacking code	[ ]	[ ]	[ ]	[ ]
video decode accel, lacking code	[ ]	[ ]	[ ]	[ ]
PWM audio, lacking code	[ ]	[ ]	[ ]	[ ]
booting Linux	?	[x]	?	?
Ethernet (including mac address from rpi serial number)	?	[x]	?	?
USB host (under linux)	?	[x]	?	?
SD/MicroSD: works 95% of the time	?	[x]	?	?

projects:

rpi1-test

builds LK for the armv6 found on the pi0 and pi1

currently not working on this overlay

rpi2-test

builds LK for the cortex-A7 found in a pi2

use lk.bin as your kernel.img file, with the official firmware

rpi3-test

builds LK in aarch64 mode for the cortex-A53 found in a pi3

use lk.bin as your kernel.img file, with the official firmware

rpi3-bootcode

builds LK for the VPU on any VC4 pi (pi0 to pi3), use lk.bin as bootcode.bin

rpi3-start

buids LK for the VPU on any VC4 pi (pi0 to pi3), use lk.elf as start.elf, with either the official bootcode.bin or vc4-stage1

rpi4-recovery

builds LK for the VPU on a VC6 pi (pi4, pi400, CM4), use lk.bin as recovery.bin or bootcode.bin in spi flash, must be signed with https://github.com/librerpi/rpi-tools/tree/master/signing-tool

rpi4-start4

builds LK for the VPU on a VC6 pi (pi4, pi400, CM4), use lk.elf as start4.elf, with the official SPI firmware

vc4-stage1

builds LK as a bootcode.bin replacement, loads lk.elf from either an ext2 partition or xmodem over the uart

vc4-stage2

a test stage2 for use with vc4-stage1, currently it just brings the DPI online

vc4-start

a test stage2, that will embed rpi1-test into itself, and run LK on both the VPU and ARM