Re: [PATCH v2 0/3] mtd: nand: add randomizer support

[Boris Brezillon <boris.brezillon@free-electrons.com>]

Hi Brian,

Anything blocking in this series?
I was expecting to get it into 4.5, but it's too late now. Could you
consider reviewing it (in order to take it into 4.6 if everything is
OK for you)?

The reason I'd like to get this into Linux rather quickly is because I
want to port the sunxi-nand driver to u-boot, and these randomizer
stuff are required on most sunxi boards.
IOW, u-boot users would not understand if I port a NAND driver that
appears to be useless for their board(s) :-/.

Thanks,

Boris

On Wed,  2 Dec 2015 12:01:04 +0100
Boris Brezillon <boris.brezillon@free-electrons.com> wrote:

> Hello,
> 
> This series is a proposal to add support for randomizers (either software
> or hardware) to NAND flash controller drivers.
> 
> The last patch is the sunxi HW randomizer implementation and is just given
> as an example (it won't apply on the MTD tree, because it depends on other
> stuff not yet posted on the MTD ML, but if you want a full overview of the
> NAND Flash controller driver you can take a look at this series [2]).
> 
> I can also provide a software implementation based on LFSR (Left Feedback
> Shift Register) algorithm, thought I haven't tested it yet, hence why it's
> not part of this series. Let me know if you're interested in this
> implementation.
> 
> This series depends on the "per-partition ECC" series [1], because I need
> the randomizer seed to be different depending on the partition (for the
> same reason I needed ECC config to be different for each partition: the
> bootrom config might not fit the NAND chip requirements).
> 
> I'd like to have feedback from both MTD maintainers and driver
> developers who might need to implement (or use) a randomizer in their
> system, so feel free to comment on this series.
> 
> Best Regards,
> 
> Boris
> 
> [1] https://lkml.org/lkml/2014/2/12/627
> [2] https://groups.google.com/forum/#!msg/linux-sunxi/s3lBb01I0Js/z2NoCFJ83g4J 
> 
> Changes since v1:
> - add some comments to explain how the sunxi randomizer works
> - fix a few minor bugs and coding style issues
> 
> Boris Brezillon (3):
>   mtd: nand: add NAND_NEED_SCRAMBLING option flag
>   mtd: nand: add NAND_NEED_SCRAMBLING flag to the H27UCG8T2ATR-BC
>     definition
>   mtd: nand: sunxi: add randomizer support
> 
>  drivers/mtd/nand/nand_ids.c   |   4 +-
>  drivers/mtd/nand/sunxi_nand.c | 287 ++++++++++++++++++++++++++++++++++++++----
>  include/linux/mtd/nand.h      |   6 +
>  3 files changed, 269 insertions(+), 28 deletions(-)
> 



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com