mvebu: add support for Zyxel NAS326

mvebu: add support for Zyxel NAS326

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Hardware:
CPU: ARMADA 380 1x1332Mhz
RAM: 512MB DDR3
FLASH: 256MB MX30LF2G18AC
2x SATA III
2x USB3.0
1x USB2.0
i2c to control various states.
RTC with battery
1Gbit LAN (WoL capable)
9x LED
RESET button at back
Power button at front (gpio-poweroff)
Copy button at front

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Doesn't work
FAN control
buzzer

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UART connections

Connect UART to port J3 115200
+----+----+----+----+----+
|3.3V| TX | RX |    | GND|
+----+----+----+    +----+
Depend of UART adapter board can fail to boot when adapter is attached. (all leds are dimmed) .
In that case disconnect UART for an < second and after that all leds should be white.
Stop u-boot by ctrl-c within 3s window. (bootdelay 7s or more helps)
setenv bootdelay 7
saveenv

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Instalation via UART

Boot initramfs-kernel.bin
setenv ethact egiga0
setenv serverip 192.168.1.11
setenv ipaddr 192.168.1.12
tftpboot 0x02000000 *initramfs-kernel.bin
bootm 0x02000000 -

Device is DHCP client by default ( as the other supported NAS)

do backup into safe space
/dev/mtd3 Kernel-1
/dev/mtd4 RootFS-1

use sysupgrade in console or via luci

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MAC addresses

mac stored in u-boot-env ethaddr
label mac = eth0 mac =  5c:6a:80:xx:xx:xx

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Setting up u-boot  dual boot

u-boot contain two banks contain two OEM copies
To boot OpenWrt from bank1
setenv next_bootfrom 1
saveenv

To boot OEM from bank2
setenv next_bootfrom 2
saveenv

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Configuration via i2c
install i2c-tools

Enable WoL
i2cset -y 0x0 0xa 0xa 0x0006 w

Disable WoL
i2cset -y 0x0 0xa 0xa 0x0306 w

Enable auto power on
i2cset -y 0x0 0x0a 0x0a 0x0107 w

Disable auto power on
i2cset -y 0x0 0x0a 0x0a 0x0007 w

Signed-off-by: Robert Senderek <robert.senderek@10g.pl>
Link: https://github.com/openwrt/openwrt/pull/23228
Signed-off-by: Robert Marko <robimarko@gmail.com>