I just hooked up one of these to my Raspberry Pi CM dev kit.
http://www.buydisplay.com/default/4-3-tft-lcd-display-module-controller-board-w-serial-spi-i2c-mcu
I am quite impressed on their work for this. I also ran it on the arietta G25 (its a 400mhz) board and works smoothly there as well.
Check out the video on this page.
http://www.acmesystems.it/arietta_adafruit_lcd28
What i just cant wrap my head around is the Edison is faster than the G25 & on top of this has 2 cores. Why is the Edisons SPI so lame?
I have given up on it. The CS - CS delays are killing me with it, and i cannot find any reason why this is.