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    SubjectRe: [PATCH v4 00/52] mtd: rework ECC layout definition
    On Mon, Mar 07, 2016 at 10:46:50AM +0100, Boris Brezillon wrote:
    > Hello,
    >
    > This patchset aims at getting rid of the nand_ecclayout limitations.
    > struct nand_ecclayout is defining fixed eccpos and oobfree arrays which
    > can only be increased by modifying the MTD_MAX_ECCPOS_ENTRIES_LARGE and
    > MTD_MAX_OOBFREE_ENTRIES_LARGE macros.
    > This approach forces us to modify the macro values each time we add a
    > new NAND chip with a bigger OOB area, and increasing these arrays also
    > penalize all platforms, even those who only support small NAND devices
    > (with small OOB area).
    >
    > The idea to overcome this limitation, is to define the ECC/OOB layout
    > by the mean of two functions: ->ecc() and ->free(), which will
    > basically return the same information has those stored in the
    > nand_ecclayout struct.
    >
    > Another advantage of this solution is that ECC layouts are usually
    > following a repetitive pattern (i.e. leave X bytes free and put Y bytes
    > of ECC per ECC chunk), which allows one to implement the ->ecc()
    > and ->free() functions with a simple logic that can be applied
    > to any size of OOB.
    >
    > Patches 1 to 4 are just cleanups or trivial fixes that can be taken
    > independently.
    >
    > Also note that the last two commits are removing the nand_ecclayout
    > definition, thus preventing any new driver to use this structure.
    > Of course, this step can be delayed if some of the previous patches
    > are not accepted.
    >
    > All those changes are available here [1].
    >
    > Best Regards,
    >
    > Boris
    >
    > [1]https://github.com/bbrezillon/linux-0day/tree/nand/ecclayout

    FYI, I've pushed patches 1-4 to l2-mtd.git. I'll take another look at
    them this week I hope (or your new fellow, Richard, can!), then you can
    queue them up for the next cycle.

    Brian

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