oxnas

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

• 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 (?)

• 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...

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

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

The list of related devices: ToH:oxnas