Allwinner Sun4i/5i/6i/7i (sunxi)

Various vendors are offering development boards / single-board computer based on the Allwinner SoCs. These are running various flavors of the A1x/A20 SoCs, with different buildouts. The mach is called "sunxi".

For some specs rather see Allwinner_Technology#A-Series.

Supported Versions

Hardware Highlights

UEXT is an open standard port to provide serial, I²C and SPI expansion ports.

Installation

This section details what is required to install and upgrade OpenWrt. The generic procedure is described here: generic.flashing; this devices don‘t have a flash chip soldered to the PCB but an SD-Card slot.

Status

Patches have been back-ported from the http://linux-sunxi.org/ community, including device trees, clocks, timers, PIO, ethernet, USB, and, MMC.
These patches are currently being mainlined - eta. Linux 3.14 and 3.15 - by the community.

• SPL: done
• u-boot: done
• kernel: done
• rootfs: done

You have the option to boot the board from initramfs, SD card (recommended), USB storage, or NFS.

Working

• SD/MMC
• USB EHCI/OHCI
• EMAC (10/100 Mbps)
• A20 GMAC (10/100/1000 Mbps)
• SATA
• Clocks
• Timers
• SMP with HYP patches for 2014.04 u-boot
• Various devices, GPIO, IR

Being worked on

• NAND (have some snippets already)
• SPI (need integration)

Not being worked on

• Sound - need bump to 3.18

Installation process

Pre-built SD card images

You can build an SD card image directly from buildroot for your device.

• Check out trunk - https://dev.openwrt.org/wiki/GetSource
• Run make menuconfig
• Select device profile - f.e. BananaPi
• Start the build
• The built SD card images will be in bin/sunxi
• dd if=bin/sunxi/openwrt-sunxi-Bananapi-sdcard-vfat-ext4.img of=/dev/sdc

Assembling the SD card image yourself

OpenWrt trunk images are located in snapshots/trunk/sunxi/ folder.

For example if you have Cubieboard3/Cubietruck then download these files from the server:

• openwrt-sunxi-Cubietruck-u-boot-with-spl.bin
• openwrt-sunxi-Cubietruck-uEnv.txt
• sun7i-a20-cubietruck.dtb
• openwrt-sunxi-uImage
• openwrt-sunxi-root.ext4

SD layout

SD layout with 512 byte blocks:

SD preparation

We assume /dev/mmcblk0 is the SD card and Cubietruck is the board.

• Partition the SD card. Two partitions are created. The first is the boot partition, /dev/mmcblk0p1. The second is the root partition, /dev/mmcblk0p2.

# fdisk /dev/mmcblk0

Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-15523839, default 2048): 2048
Last sector, +sectors or +size{K,M,G} (2048-15523839, default 15523839): +15M 

Command (m for help): n
Partition type:
   p   primary (1 primary, 0 extended, 3 free)
   e   extended
Select (default p): p
Partition number (1-4, default 2): 2
First sector (32768-15523839, default 32768): 32768
Last sector, +sectors or +size{K,M,G} (32768-15523839, default 15523839): +240M

Command (m for help): p

Disk /dev/mmcblk0: 7948 MB, 7948206080 bytes
4 heads, 16 sectors/track, 242560 cylinders, total 15523840 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x17002d14

        Device Boot      Start         End      Blocks   Id  System
/dev/mmcblk0p1            2048       32767       15360   83  Linux
/dev/mmcblk0p2           32768      524287      245760   83  Linux

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

• Re-read the new partition table layout (e.g. by removing and re-inserting the SD card).
• Copy the SPL + U-boot image to the card

# dd if=bin/sunxi/uboot-sunxi-Cubietruck/openwrt-sunxi-Cubietruck-u-boot-with-spl.bin of=/dev/mmcblk0 bs=1024 seek=8

• Create a boot (FAT32) partition.

# mkfs.vfat /dev/mmcblk0p1

• Mount the boot partition.

# mount -t vfat /dev/mmcblk0p1 /mnt

• Copy the U-Boot environment file uEnv.txt to the boot partition.

# cp bin/sunxi/uboot-sunxi-Cubietruck/openwrt-sunxi-Cubietruck-uEnv.txt /mnt/uEnv.txt

• Copy the device tree data to the boot partition.

# cp bin/sunxi/sun7i-a20-cubietruck.dtb /mnt/dtb

• Copy the kernel image to the boot partition.

# cp bin/sunxi/openwrt-sunxi-uImage /mnt/uImage

• Resize the root filesystem image to match the partition size.

# resize2fs bin/sunxi/openwrt-sunxi-root.ext4 240M

• Create the root filesystem.

# dd if=bin/sunxi/openwrt-sunxi-root.ext4 of=/dev/mmcblk0p2 bs=128k

• Wrap up (flush buffers and unmount boot partition).

# sync
# umount /mnt

Upgrading OpenWrt

→generic.sysupgrade

*WiP*

If you have already installed OpenWrt and like to reflash for e.g. upgrading to a new OpenWrt version you can upgrade using the mtd command line tool. It is important that you put the firmware image into the ramdisk (/tmp) before you start flashing.

Links

For further information about the SoCs, go to http://linux-sunxi.org/Main_Page

How can you help

• We‘re looking for any A31 / A80 hardware at the moment
• Hardware donations - https://dev.openwrt.org/wiki/WantedHardware
• Test GPIOs and peripherals on A13/A20 and provide feedback