oxnas

oxnas

A family of ARM-based SoCs developed by Oxford Semi, later sold to PLXTECH.

SoC	cores	S-ATA	PCIe	GigE	OpenWrt support
OX815SE	ARM10	1	-	1	no
OX815DSE	ARM10	2	-	1	no
OX820 NAS7820	2x ARM11MPcore	2	1	1	yes
OX821 NAS7821	2x ARM11MPcore	2	1	1	yes
NAS7825	2x ARM11MPcore	2	2	2	?

OX82x / NAS782x architecture overview

2x ARM11MPCORE (ARMv7) core
LEON2 (SPARC v8) co-processor usable for power-management and DMA offloading tasks
no PCIe on OX820/NAS7820, 1x PCIe on OX821/NAS7821, 2x PCIe on NAS7825
up to 512MB DDR2 SDRAM
NAND or SPI serial flash (128MiB NAND typically found in the wild)
DesignWare/ST GigE core with GMII/RMGII (2x in NAS7825)
EHCI USB 2.0 Host (USB gadget mode might be possible as well)
OX934 single-DMA dual-port S-ATA controller (SoC supports JBOD and RAID0/1 in hardware, OpenWrt doesn't yet)
2x DesignWare/Synopsis S-ATA phy
Crypto engine (?)

History and availability

originally developed at Oxford Semi
Oxford Semi acquired by PLXTECH, NAS products renamed
PLXTECH acquired by Avago, announced end-of-life for NAS products
however, Avago got bulk-agreement with Rochester…

Known Limitations

The OpenWrt oxnas target doesn't support all hardware features of the SoC.

vendor's U-Boot doesn't support booting modern kernels
- chain-load a recent U-Boot which does
  This additional U-Boot stage uses UBI to load OpenWrt and stores it's environment in UBI
  In future, it may instead be feasible to replace the stock loader, kwboot-like serial recovery yet needs to be found…
  - PLL and SDRAM setup is board specific and needs to be taken care of if we want that

S-ATA core requires host-lock for port transfers
- S-ATA performance sucks when using both drivers simultanously e.g. for RAID-1
  vendor's Linux SDK uses hardware-supported RAID and JBOD, OpenWrt doesn't (yet)
  reference code: https://github.com/kref/linux-oxnas/blob/reference/sdk/drivers/md/ox820hwraid.c

no USB gadget support

USB 1.1 isochronous transfers are broken. As a work-around an extra USB 2.0 hub between the oxnas box and USB 1.x devices making use of isochronous transfers (e.g. USB audio interfaces) can be used.

Crypto engine undocumented/unsupported in all known GPL drops, no support in OpenWrt

LEON microcode loading not yet implemented, thus no watchdog and wake-on-lan
reference code: https://github.com/kref/linux-oxnas/blob/reference/sdk/arch/arm/plat-oxnas/leon.c
The GPL tarball WD-GPL-v1.18 of the Western Digital “My Book World Edition II (blue rings)” contains toolchain and sources of some LEON programs meant to be used with older oxnas SoCs. Besides the addresses, this looks very much the same as on newer SoCs.

no decent hddtemp-driven fancontrol for devices with fan implemented in OpenWrt
reference code: https://github.com/kref/linux-oxnas/blob/reference/sdk/arch/arm/plat-oxnas/thermAndFan.c
https://github.com/kref/linux-oxnas/blob/reference/sdk/arch/arm/plat-oxnas/thermistorCalibration.h

The Chaos Calmer 15.05 images for the Oxnas targets are missing some essential packages and kernel modules, most notably iptables and the conntrack kernel modules which are required for the firewall to work correctly. If you reconfigure the firewall or network (for example to create a WAN interface), be sure to install the respective packages beforehand.

Supported boards/devices

k=known backdoor
i=installer/flash image available
h=how-to available
s=serial access required for installation
0=missing fdt, please get in touch if you got that board/device and want to help porting or loan or donate hardware

board name	product name	status	wiki page
stg-212	ZyXEL NSA-212 / MitraStra STG-212 / Medion …	k,h	md86587
pogoplug-pro	Cloud Engines PogoPlug Pro (with mPCIe slot)	k,s	Pogoplug Pro
pogoplug-v3	Cloud Engines PogoPlug v3 (no PCIe)	k,s	pogoplugpro
kd20	Shuttle KD20	i
ch3hnas2	Conceptronic CH3HNAS2	0
em4172	Eminent EM4172 / Akitio MyCloud Duo	0
hmnhdce	iomega Home Media Network Hard Drive Cloud Edition	0
akitio	Silverstone DC01 / Akitio MyCloud mini	s
voyager	Corsair Voyager Air	0

Devices

The list of related devices: ToH:oxnas