RE: [EXT] Re: [PATCH 6/8] mtd: spinand: micron: Turn driver implementation generic

From: Shivamurthy Shastri (sshivamurthy)
Date: Mon Aug 19 2019 - 05:03:46 EST


Hi Miquel,

>
> Hi Shiva,
>
> shiva.linuxworks@xxxxxxxxx wrote on Mon, 22 Jul 2019 07:56:19 +0200:
>
> > From: Shivamurthy Shastri <sshivamurthy@xxxxxxxxxx>
> >
>
> I am not sure the "turn implemenatation generic" title describes what
> you do.
>
> > Driver is redesigned using parameter page to support Micron SPI NAND
> > flashes.
>
> Redesigned is perhaps a bit too much.
>
> "
> > The reason why spinand_select_op_variant globalized is that the Micron
> > driver no longer calling spinand_match_and_init.
> >
> > Signed-off-by: Shivamurthy Shastri <sshivamurthy@xxxxxxxxxx>
> > ---
> > drivers/mtd/nand/spi/core.c | 2 +-
> > drivers/mtd/nand/spi/micron.c | 61 +++++++++++++++++++++++++-------
> ---
> > include/linux/mtd/spinand.h | 4 +++
> > 3 files changed, 49 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
> > index 7ae76dab9141..aae715d388b7 100644
> > --- a/drivers/mtd/nand/spi/core.c
> > +++ b/drivers/mtd/nand/spi/core.c
> > @@ -920,7 +920,7 @@ static void spinand_manufacturer_cleanup(struct
> spinand_device *spinand)
> > return spinand->manufacturer->ops->cleanup(spinand);
> > }
> >
> > -static const struct spi_mem_op *
> > +const struct spi_mem_op *
> > spinand_select_op_variant(struct spinand_device *spinand,
> > const struct spinand_op_variants *variants)
> > {
> > diff --git a/drivers/mtd/nand/spi/micron.c
> b/drivers/mtd/nand/spi/micron.c
> > index 95bc5264ebc1..6fde93ec23a1 100644
> > --- a/drivers/mtd/nand/spi/micron.c
> > +++ b/drivers/mtd/nand/spi/micron.c
> > @@ -90,22 +90,10 @@ static int micron_ecc_get_status(struct
> spinand_device *spinand,
> > return -EINVAL;
> > }
> >
> > -static const struct spinand_info micron_spinand_table[] = {
> > - SPINAND_INFO("MT29F2G01ABAGD", 0x24,
> > - NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 2, 1, 1),
> > - NAND_ECCREQ(8, 512),
> > - SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
> > - &write_cache_variants,
> > - &update_cache_variants),
> > - 0,
> > - SPINAND_ECCINFO(&micron_ooblayout_ops,
> > - micron_ecc_get_status)),
> > -};
> > -
>
> I don't know if it is wise to drop this structure.
>
> > static int micron_spinand_detect(struct spinand_device *spinand)
> > {
> > + const struct spi_mem_op *op;
> > u8 *id = spinand->id.data;
> > - int ret;
> >
> > /*
> > * Micron SPI NAND read ID need a dummy byte,
> > @@ -114,16 +102,55 @@ static int micron_spinand_detect(struct
> spinand_device *spinand)
> > if (id[1] != SPINAND_MFR_MICRON)
> > return 0;
> >
> > - ret = spinand_match_and_init(spinand, micron_spinand_table,
> > - ARRAY_SIZE(micron_spinand_table),
> id[2]);
>
> I am not sure this is the right solution. I would keep this call and
> overwrite what you need to overwrite with the fixup hook.
>

Then, I will have dummy structure like below.

static const struct spinand_info micron_spinand_table[] = {
SPINAND_INFO(NULL, 0,
NAND_MEMORG(0, 0, 0, 0, 0, 0, 0, 0, 0),
NAND_ECCREQ(0, 0),
SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
&write_cache_variants,
&update_cache_variants),
0,
SPINAND_ECCINFO(&micron_ooblayout_ops,
micron_ecc_get_status)),
};

Let me know if you are thinking for different approach.

> > - if (ret)
> > - return ret;
> > + spinand->flags = 0;
> > + spinand->eccinfo.get_status = micron_ecc_get_status;
> > + spinand->eccinfo.ooblayout = &micron_ooblayout_ops;
> > +
> > + op = spinand_select_op_variant(spinand,
> > + &read_cache_variants);
> > + if (!op)
> > + return -ENOTSUPP;
> > +
> > + spinand->op_templates.read_cache = op;
> > +
> > + op = spinand_select_op_variant(spinand,
> > + &write_cache_variants);
> > + if (!op)
> > + return -ENOTSUPP;
> > +
> > + spinand->op_templates.write_cache = op;
> > +
> > + op = spinand_select_op_variant(spinand,
> > + &update_cache_variants);
> > + spinand->op_templates.update_cache = op;
> >
> > return 1;
> > }
> >
> > +static void micron_fixup_param_page(struct spinand_device *spinand,
> > + struct nand_onfi_params *p)
> > +{
> > + /*
> > + * As per Micron datasheets vendor[83] is defined as
> > + * die_select_feature
> > + */
> > + if (p->vendor[83] && !p->interleaved_bits)
> > + spinand->base.memorg.planes_per_lun = 1 << p-
> >vendor[0];
> > +
> > + spinand->base.memorg.ntargets = p->lun_count;
> > + spinand->base.memorg.luns_per_target = 1;
> > +
> > + /*
> > + * As per Micron datasheets,
> > + * vendor[82] is ECC maximum correctability
> > + */
> > + spinand->base.eccreq.strength = p->vendor[82];
> > + spinand->base.eccreq.step_size = 512;
> > +}
> > +
> > static const struct spinand_manufacturer_ops
> micron_spinand_manuf_ops = {
> > .detect = micron_spinand_detect,
> > + .fixup_param_page = micron_fixup_param_page,
> > };
> >
> > const struct spinand_manufacturer micron_spinand_manufacturer = {
> > diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
> > index fea820a20bc9..ddb2194273a8 100644
> > --- a/include/linux/mtd/spinand.h
> > +++ b/include/linux/mtd/spinand.h
> > @@ -461,4 +461,8 @@ int spinand_match_and_init(struct spinand_device
> *dev,
> > int spinand_upd_cfg(struct spinand_device *spinand, u8 mask, u8 val);
> > int spinand_select_target(struct spinand_device *spinand, unsigned int
> target);
> >
> > +const struct spi_mem_op *
> > +spinand_select_op_variant(struct spinand_device *spinand,
> > + const struct spinand_op_variants *variants);
> > +
> > #endif /* __LINUX_MTD_SPINAND_H */
>
>
>
>
> Thanks,
> MiquÃl