Nintendo Wii U support added to -current

[Jared McNeill <jmcneill%invisible.ca@localhost>]

Yesterday I committed support for the Nintendo Wii U to NetBSD -current.

The Wii U is a very nice upgrade from the Wii:

 * CPU is a 1.24GHz tri-core PowerPC (IBM 750 derivative)
 * 2GB RAM
 * GPU is AMD Radeon (probably R7xx)
 * HDMI / composite / component video out
 * 4x USB 2.0 ports
 * SD card slot
 * SATA Blu-ray drive
 * Touch screen, buttons, camera integrated into the controller

To get NetBSD up and running, you need a homebrew-enabled system. You can 
do this with an SD card and internet connection, no additional hardware 
required. Follow the instructions for installing Aroma on 
https://wiiu.hacks.guide to prepare the system for installation. This only 
needs to be done once.

Once the system is homebrew-enabled, prepare an SD card with the NetBSD 
install. I _strongly_ recommend using an A2-class microSD card for this.

Files required:

 * https://nycdn.netbsd.org/pub/NetBSD-daily/HEAD/latest/evbppc/binary/gzimg/nintendo.img.gz
 * https://github.com/wiiu-env/fw_img_payload/releases/download/v0.2/fw_img_payload_v0_2.zip
 * https://gitlab.com/linux-wiiu/linux-loader/-/jobs/artifacts/master/raw/fw.img?job=loader-build

To setup the SD card:

 1) Uncompress nintendo.img.gz and image the SD card using your
    favourite image writing software (dd, balenaEtcher, etc).
 2) Mount the new FAT file-system that was written to the SD card. You
    should see a directory named "linux" and a file named "netbsd" in the
    root directory. Make a new directory named "wiiu".
 3) Uncompress fw_img_payload_v0_2.zip and copy "payload.elf" to the
    "wiiu" directory.
 4) Copy linux-loader to the root directory as "fw.img".

The final layout of the FAT file-system should look something like this:

   fw.img
   linux/boot.cfg
   netbsd
   wiiu/payload.elf

(There will be other files present, those are to support the original Wii).

Power on the Wii U with this SD card installed and the system should boot 
automatically into NetBSD. On first boot, it will grow the FFS file-system 
to fill the entire SD card and reboot once, this is expected. Once it 
boots a second time, you can login as "root" and use the system as any 
other NetBSD install.

Take care,
Jared