Re: [PATCH v4 8/9] mtd: rawnand: ingenic: Add support for the JZ4725B

[Paul Cercueil]

Hi Miquel,

Le lun. 4 mars 2019 à 16:09, Miquel Raynal <miquel.raynal@xxxxxxxxxxx> 
a écrit :
> Hi Paul,
>
> Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote on Mon, 04 Mar 2019 
> 19:30:04
> +0100:
>
> >  On Mon, Mar 4, 2019 at 11:35 AM, Miquel Raynal 
> > <miquel.raynal@xxxxxxxxxxx> wrote:
> >  > Hi Paul,
> >  >
> >  > Paul Cercueil <paul@xxxxxxxxxxxxxxx 
> > <mailto:paul@xxxxxxxxxxxxxxx>> > wrote on Sat,  9 Feb 2019 16:23:04
> >  > -0300:
> >  >
> >  >>  The boot ROM of the JZ4725B SoC expects a specific OOB layout 
> > on the
> >  >>  NAND, so we use it unconditionally in the ingenic-nand driver.
> >  >> >>  Also add the jz4725b-bch driver to support the 
> > JZ4725B-specific BCH
> >  >>  hardware.
> >  >> >>  Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx >> 
> > <mailto:paul@xxxxxxxxxxxxxxx>>
> >  >>  ---
> >  >> >>  Changes:
> >  >> >>  v2: Instead of forcing the OOB layout, leave it to the board 
> > code or
> >  >>      devicetree to decide if the jz4725b-specific layout should 
> > be >> used
> >  >>      or not.
> >  >> >>  v3: - Revert the change in v2, as the previous behaviour was 
> > >> correct.
> >  >>      - Also add support for the hardware BCH of the JZ4725B in 
> > this
> >  >>        patch.
> >  >> >>  v4: - Add MODULE_* macros
> >  >>      - Add tweaks suggested by upstream feedback
> >  >> >>   drivers/mtd/nand/raw/ingenic/Kconfig        |  10 +
> >  >>   drivers/mtd/nand/raw/ingenic/Makefile       |   1 +
> >  >>   drivers/mtd/nand/raw/ingenic/ingenic_nand.c |  48 ++++-
> >  >>   drivers/mtd/nand/raw/ingenic/jz4725b_bch.c  | 292 >> 
> > ++++++++++++++++++++++++++++
> >  >>   4 files changed, 350 insertions(+), 1 deletion(-)
> >  >>   create mode 100644 drivers/mtd/nand/raw/ingenic/jz4725b_bch.c
> >  >> >
> >  > [...]
> >  >
> >  >>  +static int jz4725b_calculate(struct ingenic_ecc *bch,
> >  >>  +			     struct ingenic_ecc_params *params,
> >  >>  +			     const u8 *buf, u8 *ecc_code)
> >  >>  +{
> >  >>  +	int ret;
> >  >>  +
> >  >>  +	mutex_lock(&bch->lock);
> >  >>  +	ret = jz4725b_bch_init(bch, params, true);
> >  >
> >  > I really don't like this bch_init name. A BCH initialization is 
> > what > is
> >  > supposed to be done only once (probably at boot time), can you 
> > find a
> >  > better name or a better organization of the correct/calculate 
> > path?
> >
> >  jz4725b_bch_setup() maybe?
>
> Unless I am not understanding what this does, I don't get why you 
> would
> need to do this setup everytime you want to use the ECC engine. Are 
> you
> sure this is needed?

It configures the hardware for a new ECC encoding or decoding sequence, 
so
yes, it has to be done everytime.

-Paul