Reading from multiple die stacked NAND flssh memory with flashrom

[s3th_0x]

Hi all,

I'm interested in reading from a Winbond's NAND Flash Memory W25M02GV <https://www.winbond.com/resource-files/W25M02GV%20Rev%20I%20051721.pdf>, but unfortunately  flashrom does not support this chip yet. There are few differences between this chip and those already available in the flashchips.h from Winbond.
It uses a SpiStack technology, which means stacking multiple die in one, in this case two nand 1G each. The ID for this nand is W25N01GV <https://www.winbond.com/resource-files/W25M02GV%20Rev%20I%20051721.pdf>. Actually the W25M02GV <https://www.winbond.com/resource-files/W25M02GV%20Rev%20I%20051721.pdf> is composed by two W25N01GV <https://www.winbond.com/resource-files/W25M02GV%20Rev%20I%20051721.pdf> NAND.
this chip, for almost every instruction, has one or more dummy bytes after the instruction. This feature seems not to be implemented in any chip currently listed in flashrom.
Also, my fault, I admit that I don't fully understand all the differences that could be hidden in having more than one die (perhaps more than the ones I mentioned above), and consequently the implications that it could entail in the implementation.

I hope someone will be interested in developing this ability and can help me.

Thanks,
s3th0x

References:
Datasheet: https://www.winbond.com/resource-files/W25M02GV%20Rev%20I%20051721.pdf
Linux Kernel MTD: https://elixir.bootlin.com/linux/latest/source/drivers/mtd/nand/spi/winbond....
Arduino Library: https://github.com/squaresausage/WinbondW25N