More importantly, I received the internal test board from WRTnode team. It is the WRTnode 2Q, featuring a Qualcomm Atheros QCA9531 chip.
This board integrates a ETH switch, and 802.11n ath9k wifi radio.
128Mbyte RAM, 16Mbyte Flash, 300Mhz 11n 2T2Rspi , i2c , gpio , PCI-e , USB2.0
This is quite enough for all the applications relate to linux. And the price is about 15USD when quantity is around 1k.
The module itself is NGFF.2 card compatible.
We can see from the LEDE project’s git that the WRTnode 2Q has been supported: Click here
WRTnode2P is equipped with MediaTek’s MT7628, which has more UART ports
The way of using peripherals like SPI, I2C, GPIO for ar71xx is not integrated into device tree yet, LEDE is planning to do so soon.