[U-Boot] [BUG] efiloader: cannot boot OpenBSD on armv7 via bootefi

[Heinrich Schuchardt]

Hello Nedko,

you reported on the IRC channel:

<nedko> i'm trying to get openbsd-6.4 kernel booted with latest u-boot.
it works with both v2018.09 and v2019.01, but not with latest git
<nedko> i'm reproducing this with default configs for sunxi lime2-emmc
<nedko> it seems that openbsd kernel loading stage is going well, but
then execution does not happen, there is no "OpenBSD/armv7 booting ..."

Olimex A20-OLinuXino-LIME2-eMMC uses the ARMv7 architecture.

The relevant source for the OpenBSD bootloader can be found at

https://github.com/openbsd/src.git in sys/arch/armv7/stand/efiboot/

While on the armv8 architecture SetVirtualAddressMap() is called it is
not called for armv7.

Alex has described in patch

efi_loader: Patch non-runtime code out at ExitBootServices already
https://lists.denx.de/pipermail/u-boot/2019-January/356845.html

that currently U-Boot does not support booting without calling
SetVirtualAddressMap() and provided a fix.

The patch has not been merged due to requested changes.

I tried to reproduce the problem on a BananaPi

This was my recipe:
Copy
https://ftp.eu.openbsd.org/pub/OpenBSD/6.4/armv7/miniroot-cubox-64.fs
to an SD-Card.
Add Linux sun7i-a20-bananapi.dtb to the first partition.
Flash Bananapi_defconfig U-Boot v2019.04-rc3 to the SD-Card

After resetting the board the installer started. All further reboots
failed even with Alex's patch applied.

Further analysis is needed.

Best regards

Heinrich