unit 的lcd不显示

[zjmitxwz]

[ 2.597060] Console: switching to colour frame buffer device 30x16
[ 2.603814] graphics fb1: fb_st7789vw frame buffer, 240x135, 63 KiB video memory, 4 KiB buffer memory, fps=20, spi0.0 at 50 MHz
[ 2.627212] sun4i-codec 1c22c00.codec: Codec <-> 1c22c00.codec mapping ok
[ 2.637300] Initializing XFRM netlink socket
[ 2.642159] NET: Registered protocol family 10
kernel加载了，修改boot.cmd显示到lcd但是lcd没有显示，用quark-n镜像里面的示例代码也不能显示