MTD with non-power-of-2 page size

[Dave Kitchen]

I have just started to work with barebox on an Atmel at91sam9g45 processor.
The board has an Atmel AT45DB161 dataflash configured as 528-byte page size.
I find that eg saveenv command does not run as the page erase fails with 
EINVAL. On tracing this is fired from the page size and offset 
correction code [mtd/core,c mtd_erase_align()] which uses bit masking to 
align the size and offset. Unfortunately bit-masking does not work with 
non-power-of-2 pages. Has anyone else addressed this problem?

The 'trivial' exercise of replacing the bit masks by modulo [%] operator 
does not succeed as the compiler I am using (gcc!) does not support 
long-long divmod.

Regards
Dave Kitchen
InSync technology Ltd