[[!meta title="NetBSD/evbarm on Allwinner Technology SoCs"]]

[[!toc levels=2]]

# Supported boards
 - [Banana Pi](http://www.bananapi.org/p/product.html) (BPI)
 - Cubieboard, Cubieboard 2 (CUBIEBOARD)
 - Cubietruck (CUBIETRUCK)
 - [Merrii Hummingbird A31](http://www.merrii.com/en/pla_d.asp?id=172) (HUMMINGBIRD_A31)

# Supported hardware
 - SoCs
   - Cortex-A8: A10
   - Cortex-A7: A20, A31
 - SD/MMC controller (DMA)
 - DMA controller
 - GPIO
   - Configuration using FEX scripts is supported
 - UART
 - I2C
 - P2WI (A31)
 - PMU
   - AXP209 (A20)
   - AXP221 (A31)
 - Watchdog timer
 - RTC
 - Audio codec
 - USB host
   - OHCI
   - EHCI
   - OTG (not yet working on A31)
 - SATA (A10/A20)
 - Gigabit Ethernet (GMAC)

# TODO
 - MULTIPROCESSOR is not yet stable
 - HDMI (some work completed here for A20)
 - Framebuffer
 - OTG (A31)
 - USB device mode
 - Bluetooth / WiFi (Cubietruck, Hummingbird A31)
 - 3G (Hummingbird A31)
 - SD/MMC UHS-I support (needs sdmmc(4) changes)
 - TV input (Hummingbird A31)
 - NAND
 - Fast Ethernet (EMAC)

# Installation

## A10 / A20 based boards

* Start with an ARMv7 image from *evbarm-earmv7hf/binary/gzimg/* such as *beaglebone.img*
* Download a U-Boot build for your board from the linux-sunxi web site <http://dl.linux-sunxi.org/nightly/u-boot-sunxi/u-boot-sunxi/u-boot-sunxi-latest/>
* Write the *u-boot-sunxi-with-spl.bin* loader to the base image:
[[!template  id=programlisting text="""
# dd if=u-boot-sunxi-with-spl.bin of=beaglebone.img bs=1k seek=8 conv=notrunc
"""]]
* Write the image to an SD card.
* Copy the kernel (netbsd.ub) for your board to the root of the MS-DOS partition.
* Create or edit uEnv.txt on the MS-DOS partition:
[[!template  id=programlisting text="""
bootargs=root=ld0a
uenvcmd=mmc dev 0; mmc rescan; fatload mmc 0:1 82000000 netbsd.ub; bootm 82000000
"""]]

## A31 based boards

TBD.

# Big (endian) fun

You can run this boards with a little endian (this is the default and implied by above install instructions)
or with a big endian kernel and userland. However, kernel and userland endianness needs to match.

To build a big endian release (or sets) use 
[[!template  id=programlisting text="""
./build.sh -m evbearmv7hf-eb 
"""]]
where -eb means endianness big, hf is hardware floating point support, and earm is the modern "extended" ABI for ARM CPUs, and finally v7 is version 7 of the supported instruction set.

# Board specific notes

## Merrii Hummingbird A31

There doesn't appear to be a meaningful way to generate a MAC address on these boards. U-Boot from the A31 SDK and from the u-boot-sunxi tree both lack GMAC support, and the Security ID registers (at 0x01c23800) appear to be empty.

To overcome this, you can specify your own MAC address in *uEnv.txt*:
[[!template  id=programlisting text="""
bootargs=root=ld0a awge0.mac-address=02:a0:3d:88:1a:1e
"""]]