Allwinner D1

FreeBSD Support

Driver support status

Device/Feature	Status	Commits	Notes
UART	Done
PLIC	Done	7339a8bd9739, 47ca5d103f
clk/reset	Done	c5c02a131a0e	`d1-r-ccu` not implemented; unclear who is/will be the consumer of these clocks
RTC	Done	9ddd516b8862	`aw_rtc(4)`, changes required
Timer	In-progress		`a10_timer(4)`, needed because SBI timer interface is not implemented
MMC	In-progress		`aw_mmc(4)`, changes required
Ethernet	In-progress		`if_awg(4)`
GPIO	In-progress		`aw_gpio(4)`
USB	In-progress		`aw_usbphy(4)`, `generic_fdt_ehci(4)`, `generic_fdt_ohci(4)`
USB OTG	In-progress		`musbotg(4)`
SPI	Unknown		Untested, supported by `aw_spi(4)`
I2C	Unknown		Untested, supported by `a10_twsi(4)`
Crypto Engine	Unsupported		No existing driver for allwinner crypto engine, `sun20i-d1-crypto`
Power domain	Unsupported		No existing driver for `sun20i-d1-ppu`

CPU support status

T-HEAD C906 WIP

Development branch

Available at https://github.com/mhorne/freebsd/tree/d1-dev.

The branch contains changes necessary to boot FreeBSD. It may be updated (force-push'd) without notice.

Firmware

Support for the T-HEAD C906 SoC is present upstream in OpenSBI. Install the sysutils/opensbi port or package.

u-boot support for the Nezha board is available in a custom fork, but has not been upstreamed. It is unclear if this will ever happen. https://github.com/smaeul/u-boot/tree/d1-wip

Build u-boot:

# Install prerequisites
pkg install opensbi riscv64-none-elf-gcc

# Clone repo
git clone https://github.com/smaeul/u-boot/tree/d1-wip u-boot-d1
cd u-boot-d1

# Configure + build
gmake nezha_defconfig
gmake -j8 CROSS_COMPILE=riscv64-none-elf- OPENSBI=/usr/local/share/opensbi/lp64/generic/firmware/fw_dynamic.bin

Note: configs for other boards are dongshan_nezha_stu_defconfig, lichee_rv_86_panel_defconfig, lichee_rv_dock_defconfig, and mangopi_mq_pro_defconfig.

Prepare SD Card

Fetch the latest GENERICSD image from https://download.freebsd.org/snapshots/riscv/riscv64/ISO-IMAGES/

Copy it to your drive:

# Extract it.
xz --decompress FreeBSD-GENERICSD.img.xz

# Copy using dd(1) to your SD device. The example is /dev/da0, but CHECK BEFORE YOU WRITE!
dd if=/path/to/FreeBSD-GENERICSD.img of=/dev/da0 bs=2m conv=sync status=progress

Inspect the result and delete unneeded firmware partitions:

# List the new partition table
gpart show da0
=>      40  12582832  da0  GPT  (30G) [CORRUPT]
        40      4056       - free -  (2.0M)
      4096      4096    1  hifive-fsbl  (2.0M)
      8192      8192    2  hifive-bbl  (4.0M)
     16384    110592    3  efi  (54M)
    126976  12455808    4  freebsd-ufs  (5.9G)
  12582784        88       - free -  (44K)


# Rewrite the backup GPT table
gpart recover da0

# Delete partitions (optional, but 'correct')
gpart delete -i 1 da0
gpart delete -i 2 da0

# Result:
gpart show da0
=>      40  62333872  da0  GPT  (30G)
        40     16344       - free -  (8.0M)
     16384    110592    3  efi  (54M)
    126976  12455808    4  freebsd-ufs  (5.9G)
  12582784  49751128       - free -  (24G)

Copy the u-boot firmware file, built previously.

dd if=/path/to/u-boot/u-boot-sunxi-with-spl.bin of=/dev/da0 bs=1k seek=128 conv=sync

Finally, install the custom kernel built from the dev branch:

mount /dev/da0p4 /mnt
cd /path/to/freebsd-src

make DESTDIR=/mnt TARGET=riscv installkernel
umount /mnt

You can make any other desired tweaks to the system before unmounting.

Upon first boot, the root partition will be automatically resized to fill the remaining space, and a swap partition will be added.

...

Starting file system checks:
/dev/ufs/rootfs: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ufs/rootfs: clean, 569155 free (1147 frags, 71001 blocks, 0.1% fragmentation)
Growing root partition to fill device
Adding swap partition
mmcsd0 recovering is not needed
mmcsd0p1 added
mmcsd0p4 resized
super-block backups (for fsck_ffs -b #) at:
 12804672, 14085120, 15365568, 16646016, 17926464, 19206912, 20487360,
 21767808, 23048256, 24328704, 25609152, 26889600, 28170048, 29450496,
 30730944, 32011392, 33291840, 34572288, 35852736, 37133184, 38413632,
 39694080, 40974528, 42254976, 43535424, 44815872, 46096320, 47376768,
 48657216, 49937664, 51218112, 52498560, 53779008, 55059456, 56339904, 57620352
Metadata value stored on mmcsd0p1.
Done.

...

root@generic:~ # gpart show
=>      40  62333872  mmcsd0  GPT  (30G)
        40     16344          - free -  (8.0M)
     16384    110592       3  efi  (54M)
    126976  58077184       4  freebsd-ufs  (28G)
  58204160   4128768       1  freebsd-swap  (2.0G)
  62332928       984          - free -  (492K)

Notes

Apparently the hardware does not have a static MAC address written in ROM; or u-boot doesn't know how to find it:

Warning: ethernet@4500000 (eth0) using random MAC address - 8e:e7:ab:cb:e0:fe

Each boot will generate a new MAC address, which is problematic when trying to netboot. The solution is to execute the saveenv command. After this, u-boot will use the saved address every time.