[U-Boot] 8/16 bit support for NAND at runtime

[Vipin KUMAR <vipin.kumar@st.com>]

Hi All,

This query is wrt NAND 8/16 bit device support at runtime. Currently,
the u-boot code can support only one of these at a time.

Although the NAND device in itself can be recognized by reading the
device id, the NAND controllers may need different platform specific
initializations for different device attached.

The current u-boot is written in such a way that
1. Initializes chip->options for a particular buswidth option
2. calls board_nand_init once and proceeds to read the device id

Although it matches the buswidth selected through chip->options and the
the buswidth of device id it reads and returns an error if they don't 
match, probably a better way can be to reinitialize NAND controller 
based on 16 bit device and re-read the device id.

This way both type of devices can be supported at runtime

Please let me know your opinion on this.
Please also let me know if I am missing something

Regards
Vipin