Hi Alex,
On Tuesday 17 May 2011 15:00:45 Alex Waterman wrote:
I am working on porting U-Boot to a sequoia based PPC440 board. It boots off NAND flash via the NDFC on the PPC440. Our NAND chip has a 16 bit bus which has presented some minor problems.
Yes, until now, all 4xx boards use 8bit NAND chips.
The NDFC code is pretty much what we need except for a few functions that I made some changes to. In particular the two functions that I changed are board_nand_init() and board_nand_select_device().
What changes did you have to make? Some 8/16 bit related changes? Or something else?
However, I would like to use the rest of the NDFC code.
It should be the goal, to use *only* the common NDFC code. If you have found some bugs, or you need some changes for 16bit devices, we should try to integrate them into the common code.
All of the functions in the NDFC code are declared static so I can't access them outside of ndfc.c; is there a reason for that? Does it save code space?
One idea behind the static declarations is to not pollute the namespace.
At the moment, in the source tree I have, I just copied ndfc.c to a different source file, made the changes I needed, and compiled that.
Ughhh!
But I don't like the idea of duplicating a significant amount of code. Any suggestions on how I should proceed with this?
Yes, please see above. Please explain what changes you need exactly and we will see, if we can integrate them into the common driver.
Likewise much of our board specific support files are copies from the sequoia code. Would it be better to symlink to the ones that are not modified? Or is it OK to just copy the relevant source files into our own board directory and make minor adjustments as needed?
Usually we copy those files into a new board directly. When the similarities are too big, then we should probably think about splitting to common parts into some other directory (arch/powerpc/cpu/ppc4xx/ppc440epx.c ???).
Best regards, Stefan
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