Re: [PATCH v2 9/9] mtd: rawnand: jz4780-bch: Add support for the JZ4740

Paul Cercueil
2019-02-03T15:41:49Z

Le dim. 3 févr. 2019 à 12:07, Boris Brezillon <bbrezillon@kernel.org>
a écrit :
> On Sun, 03 Feb 2019 11:56:32 -0300
> Paul Cercueil <paul@crapouillou.net> wrote:
>
>> Le dim. 3 févr. 2019 à 11:16, Boris Brezillon
>> <bbrezillon@kernel.org>
>> a écrit :
>> > On Sun, 03 Feb 2019 10:58:13 -0300
>> > Paul Cercueil <paul@crapouillou.net> wrote:
>> >
>> >> Le dim. 3 févr. 2019 à 4:35, Boris Brezillon
>> >> <bbrezillon@kernel.org>
>> >> a écrit :
>> >> > On Sat, 2 Feb 2019 20:19:26 -0300
>> >> > Paul Cercueil <paul@crapouillou.net> wrote:
>> >> >
>> >> >> Add the backend code for the jz4780-bch driver to support
>> the
>> >> JZ4740
>> >> >> SoC from Ingenic.
>> >> >>
>> >> >> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>> >> >> ---
>> >> >>
>> >> >> Changes:
>> >> >>
>> >> >> v2: New patch
>> >> >>
>> >> >> drivers/mtd/nand/raw/ingenic/Makefile | 2 +-
>> >> >> drivers/mtd/nand/raw/ingenic/jz4740_bch.c | 173
>> >> >> ++++++++++++++++++
>> >> >> .../mtd/nand/raw/ingenic/jz4780_bch_common.c | 1 +
>> >> >> .../nand/raw/ingenic/jz4780_bch_internal.h | 1 +
>> >> >> 4 files changed, 176 insertions(+), 1 deletion(-)
>> >> >> create mode 100644
>> drivers/mtd/nand/raw/ingenic/jz4740_bch.c
>> >> >>
>> >> >> diff --git a/drivers/mtd/nand/raw/ingenic/Makefile
>> >> >> b/drivers/mtd/nand/raw/ingenic/Makefile
>> >> >> index f38b467490cf..d16c96113a93 100644
>> >> >> --- a/drivers/mtd/nand/raw/ingenic/Makefile
>> >> >> +++ b/drivers/mtd/nand/raw/ingenic/Makefile
>> >> >> @@ -1,3 +1,3 @@
>> >> >> obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740_nand.o
>> >> >> obj-$(CONFIG_MTD_NAND_JZ4780) += jz4780_nand.o
>> >> jz4780_bch_common.o
>> >> >> \
>> >> >> - jz4780_bch.o jz4725b_bch.o
>> >> >> + jz4780_bch.o jz4725b_bch.o jz4740_bch.o
>> >> >
>> >> > I still don't see the point of the
>> jz4780_bch_common/jz47xxx_bch
>> >> > separation. You seem to always embed all objects anyway, so
>> you
>> >> can
>> >> > just put the code for both engines in the same source file and
>> >> decide
>> >> > which one to use based on the compat (which you already do
>> >> anyway).
>> >>
>> >> Each SoC has a different set of registers for the BCH hardware.
>> I
>> >> can
>> >> try to
>> >> cram everything into one file, but it won't be that much
>> cleaner.
>> >
>> > Then maybe they deserve separate drivers/modules.
>> >
>> > BTW, didn't you say that one IP uses Reed-Salomon instead of BCH.
>> I'd
>> > suggest prefixing structs and functions with jz47xx_ecc instead of
>> > jz47xx_bch and naming the common part jz47xx_ecc.c to reflect
>> that.
>>
>> Would it be a good idea to make a generic ECC API that the
>> jz47xx_nand
>> driver could use? Then the three jz47xx BCH codepaths could be
>> separate
>> drivers that register with the generic ECC core.
>
> Definitely. Actually, Miquel is already working on that, but I don't
> think it's a good idea to wait for this new framework to be finished
> to
> get your changes merged. So I'd recommend having a jz specific ECC API
> (pretty much the one you have in the common file expect it would be
> prefixed with _ecc instead of _bch) and convert it to the generic
> approach afterwards. Given the size of the common.c file, you can even
> put everything in jz47xx_ecc.h as inline funcs to avoid having yet
> another module.

Ok, perfect, I'll do that.
Thank you for your input!