Re: [PATCH v4 0/5] mtd: nand: Add on-die ECC support

[Brian Norris <computersforpeace@gmail.com>]

Hi David,

On Mon, Mar 31, 2014 at 05:28:52PM -0600, David Mosberger wrote:
> This patch-series is designed to go on top of Gerhard Sittig's
> patch series "mtd: nand: introduce a READMODE command".
> 
> The patches add on-die ECC support as found on some Micron flash chips.
> 
> David Mosberger (5):
>   mtd: nand: Detect Micron flash with on-die ECC (aka "internal ECC")
>     enabled.
>   mtd: nand: Add NAND_ECC_HW_ON_DIE ECC-mode.
>   mtd: nand: Enable subpage-reads on flashes with on-die ECC enabled.
>   mtd: nand: Allocate extra buffers needed for on-die ECC controller.
>   mtd: nand: Improve bitflip detection for on-die ECC scheme.

As I commented on your patches, I think this series is tied too closely
to a single flash part. I gave a few pointers where it can be unraveled
a bit, but please consider more ways to do so if possible. And ask
questions if anything is unclear or difficult.

Aside: if we continue to get more pseudo-generic features with
(relatively) small per-vendor differences, it may be time to do some
cleanup, and push some of the vendor-specific stuff into a new file
drivers/mtd/nand/nand_vendor.c. Already, I think a lot of the
nand_get_flash_type() stuff is so logically separate from much of the
NAND operation core, that maybe it should be pulled out. I don't expect
you to do this cleanup for me, but it may help guide you in determining
how to split certain functionality cleanly into pieces.

Thanks,
Brian