Hi Jeff,

On Friday 06 October 2006 19:56, Jeff Mann wrote:

It appears that the nand flash controller support recently added to u-boot for the ppc400ep/epx only supports the use of a single nand chip.

Yes. That's the current status.

The nand flash controller supports up to four devices using chip selects 0-3. I am working on making two devices work right now for my use, but I would like to update the flash-controller support. I am open for comments on this.

What I think I need to do is add an #config CFG_440_USENANDCONTROLLER option and an entry into the nand_chip struct for holding the chip select numbers for each chip. Then in addition to configuring an array of nand bases {CFG_NAND_BASE} (which would all be the same address because it is the address of the nand controller), the chip selects are put in a configured array and put into the nand_chip nand struct. The read and write functions would then need to be updated to enable the right chip select in the nand controller config register too.

Comments? Suggestions? What am I missing?

It seems to me that we are missing a board/cpu specific function to select a different NAND chip, when the device is changed via the "nand device x" command. This 440EP(x) specific function would then setup the NDFC configuration register (NDFC0_CR) to enable the desired NAND chip select. And to make it easy I suggest that NAND device 0 represents chips select 0 and so on... So no need for additional config options or config arrays.

What do you think?

Best regards, Stefan