armv6 kernel support for Raspberry Pi 3 in default aarch32 mode

[Sylvain Garrigues]

Hi,

2017-08-10 1:58 GMT+02:00 Mark Millard <markmi at dsl-only.net>:
>
> Overall: Supporting aarch32 is not automatic
> even if one starts from armv7 or specifically
> a cortex-a53 context unless one was lucky
> enough to happen to not touch or depend on
> any of the differences at any stage.


 Thanks. I guess though that it's quite easily feasible for someone
familiar with arm lower level initialization.

I can see NetBSD managed to make the armv7 kernel boot on Raspberry Pi 3
with one commit:
Get the RPI3 working (in aarch32 mode) by recognising Cortex A53 CPUs. -
https://github.com/IIJ-NetBSD/netbsd-src/commit/00335f7adc380a125d045279c1a0f5525fb557da

Same for OpenBSD folks:
http://marc.info/?l=openbsd-tech&m=145692659524971&w=2

Plus FreeBSD's RPI2 armv6 kernel does boot and recognize the cortex-a53
with qemu-aarch64:
qemu-system-aarch64 -M raspi2 -cpu cortex-a53 -m 1024 -smp 4 -kernel
kernel.bin -serial stdio -dtb rpi2.dtb

So I guess we too are really not far to boot RPI2 "armv6" kernel on
raspberry pi 2 v1.2 and raspberry pi 3.
I wish I could help.

Sylvain