Support UBI u-boot

[Andy Pont]

JH wrote...


>I added NAND and UBIFS support to my Yocto layer machine config file:
>
>UBOOT_CONFIG = "nand"
>UBOOT_CONFIG[nand] += "mx6ull_14x14_evk_config"
>UBOOT_CONFIG[nand] += "mx6ull_14x14_evk_nand_config"
>UBOOT_CONFIG[nand] += "ubi"
>UBOOT_CONFIG[nand] += "ubifs"
>
>But my u-boot.imx-nand still could not support ubi:
>
>=> ubi part rootfs
>Unknown command 'ubi' - try ‘help’
You need to start to read through the various sources to figure out for 
yourself what is going on!

Starting from the bottom, in U-Boot 2017.03 all of the command sources 
are in the “cmd” directory. The “ubi …” command are all in ubi.c.  
Reading cmd/Makefile shows that file gets added into the build if 
CONFIG_CMD_UBI is enabled.

The next place to look is whether or not that is set in your defconfig 
for U-Boot or overwritten somewhere in a recipe in your Yocto build 
environment.

-Andy.