Re: [PATCH 5/8] mtd: rawnand: Modify ->calc_ecc_bytes() hook in nand_ecc_caps

xiaolei li
2018-04-12T05:44:41Z

On Wed, 2018-04-11 at 20:57 +0200, Boris Brezillon wrote:
> On Wed, 11 Apr 2018 11:41:55 +0800
> Xiaolei Li <xiaolei.li-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org> wrote:
>
> > Maybe some controllers need more information besides step size and ecc
> > strength to calculate ECC bytes.
> >
> > struct nand_ecc_ctrl provides lots of ECC control information include
> > private ECC control data. So, add it into ->calc_ecc_bytes() interface,
> > to make this hook be more flexible.
>
> I'm not fond of this approach. Why don't you provide a different
> function for the 2 cases you have (parity = 13 and parity = 14)?
>
OK. It is achievable. Will rollback this change in patch v2.
Thanks.

> >
> > Signed-off-by: Xiaolei Li <xiaolei.li-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
> > ---
> > drivers/mtd/nand/raw/denali.c | 3 +-
> > drivers/mtd/nand/raw/denali.h | 2 +-
> > drivers/mtd/nand/raw/nand_base.c | 11 ++++--
> > include/linux/mtd/rawnand.h | 77 ++++++++++++++++++++--------------------
> > 4 files changed, 50 insertions(+), 43 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c
> > index 2a302a1..907609c 100644
> > --- a/drivers/mtd/nand/raw/denali.c
> > +++ b/drivers/mtd/nand/raw/denali.c
> > @@ -1113,7 +1113,8 @@ static void denali_hw_init(struct denali_nand_info *denali)
> > iowrite32(0xffff, denali->reg + SPARE_AREA_MARKER);
> > }
> >
> > -int denali_calc_ecc_bytes(int step_size, int strength)
> > +int denali_calc_ecc_bytes(struct nand_ecc_ctrl *ecc, int step_size,
> > + int strength)
> > {
> > /* BCH code. Denali requires ecc.bytes to be multiple of 2 */
> > return DIV_ROUND_UP(strength * fls(step_size * 8), 16) * 2;
> > diff --git a/drivers/mtd/nand/raw/denali.h b/drivers/mtd/nand/raw/denali.h
> > index 9ad33d2..644dffd 100644
> > --- a/drivers/mtd/nand/raw/denali.h
> > +++ b/drivers/mtd/nand/raw/denali.h
> > @@ -328,7 +328,7 @@ struct denali_nand_info {
> > #define DENALI_CAP_HW_ECC_FIXUP BIT(0)
> > #define DENALI_CAP_DMA_64BIT BIT(1)
> >
> > -int denali_calc_ecc_bytes(int step_size, int strength);
> > +int denali_calc_ecc_bytes(struct nand_ecc_ctrl *, int, int);
> > int denali_init(struct denali_nand_info *denali);
> > void denali_remove(struct denali_nand_info *denali);
> >
> > diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> > index d0b993f..e17abc8 100644
> > --- a/drivers/mtd/nand/raw/nand_base.c
> > +++ b/drivers/mtd/nand/raw/nand_base.c
> > @@ -6052,6 +6052,7 @@ int nand_check_ecc_caps(struct nand_chip *chip,
> > const struct nand_ecc_caps *caps, int oobavail)
> > {
> > struct mtd_info *mtd = nand_to_mtd(chip);
> > + struct nand_ecc_ctrl *ecc = &chip->ecc;
> > const struct nand_ecc_step_info *stepinfo;
> > int preset_step = chip->ecc.size;
> > int preset_strength = chip->ecc.strength;
> > @@ -6076,7 +6077,7 @@ int nand_check_ecc_caps(struct nand_chip *chip,
> > if (stepinfo->strengths[j] != preset_strength)
> > continue;
> >
> > - ecc_bytes = caps->calc_ecc_bytes(preset_step,
> > + ecc_bytes = caps->calc_ecc_bytes(ecc, preset_step,
> > preset_strength);
> > if (WARN_ON_ONCE(ecc_bytes < 0))
> > return ecc_bytes;
> > @@ -6114,6 +6115,7 @@ int nand_match_ecc_req(struct nand_chip *chip,
> > const struct nand_ecc_caps *caps, int oobavail)
> > {
> > struct mtd_info *mtd = nand_to_mtd(chip);
> > + struct nand_ecc_ctrl *ecc = &chip->ecc;
> > const struct nand_ecc_step_info *stepinfo;
> > int req_step = chip->ecc_step_ds;
> > int req_strength = chip->ecc_strength_ds;
> > @@ -6152,7 +6154,8 @@ int nand_match_ecc_req(struct nand_chip *chip,
> >
> > nsteps = mtd->writesize / step_size;
> >
> > - ecc_bytes = caps->calc_ecc_bytes(step_size, strength);
> > + ecc_bytes = caps->calc_ecc_bytes(ecc, step_size,
> > + strength);
> > if (WARN_ON_ONCE(ecc_bytes < 0))
> > continue;
> > ecc_bytes_total = ecc_bytes * nsteps;
> > @@ -6198,6 +6201,7 @@ int nand_maximize_ecc(struct nand_chip *chip,
> > const struct nand_ecc_caps *caps, int oobavail)
> > {
> > struct mtd_info *mtd = nand_to_mtd(chip);
> > + struct nand_ecc_ctrl *ecc = &chip->ecc;
> > const struct nand_ecc_step_info *stepinfo;
> > int step_size, strength, nsteps, ecc_bytes, corr;
> > int best_corr = 0;
> > @@ -6224,7 +6228,8 @@ int nand_maximize_ecc(struct nand_chip *chip,
> >
> > nsteps = mtd->writesize / step_size;
> >
> > - ecc_bytes = caps->calc_ecc_bytes(step_size, strength);
> > + ecc_bytes = caps->calc_ecc_bytes(ecc, step_size,
> > + strength);
> > if (WARN_ON_ONCE(ecc_bytes < 0))
> > continue;
> >
> > diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
> > index 5dad59b..e7c7fdb 100644
> > --- a/include/linux/mtd/rawnand.h
> > +++ b/include/linux/mtd/rawnand.h
> > @@ -507,44 +507,6 @@ static inline void nand_hw_control_init(struct nand_hw_control *nfc)
> > }
> >
> > /**
> > - * struct nand_ecc_step_info - ECC step information of ECC engine
> > - * @stepsize: data bytes per ECC step
> > - * @strengths: array of supported strengths
> > - * @nstrengths: number of supported strengths
> > - */
> > -struct nand_ecc_step_info {
> > - int stepsize;
> > - const int *strengths;
> > - int nstrengths;
> > -};
> > -
> > -/**
> > - * struct nand_ecc_caps - capability of ECC engine
> > - * @stepinfos: array of ECC step information
> > - * @nstepinfos: number of ECC step information
> > - * @calc_ecc_bytes: driver's hook to calculate ECC bytes per step
> > - */
> > -struct nand_ecc_caps {
> > - const struct nand_ecc_step_info *stepinfos;
> > - int nstepinfos;
> > - int (*calc_ecc_bytes)(int step_size, int strength);
> > -};
> > -
> > -/* a shorthand to generate struct nand_ecc_caps with only one ECC stepsize */
> > -#define NAND_ECC_CAPS_SINGLE(__name, __calc, __step, ...) \
> > -static const int __name##_strengths[] = { __VA_ARGS__ }; \
> > -static const struct nand_ecc_step_info __name##_stepinfo = { \
> > - .stepsize = __step, \
> > - .strengths = __name##_strengths, \
> > - .nstrengths = ARRAY_SIZE(__name##_strengths), \
> > -}; \
> > -static const struct nand_ecc_caps __name = { \
> > - .stepinfos = &__name##_stepinfo, \
> > - .nstepinfos = 1, \
> > - .calc_ecc_bytes = __calc, \
> > -}
> > -
> > -/**
> > * struct nand_ecc_ctrl - Control structure for ECC
> > * @mode: ECC mode
> > * @algo: ECC algorithm
> > @@ -639,6 +601,45 @@ struct nand_ecc_ctrl {
> > };
> >
> > /**
> > + * struct nand_ecc_step_info - ECC step information of ECC engine
> > + * @stepsize: data bytes per ECC step
> > + * @strengths: array of supported strengths
> > + * @nstrengths: number of supported strengths
> > + */
> > +struct nand_ecc_step_info {
> > + int stepsize;
> > + const int *strengths;
> > + int nstrengths;
> > +};
> > +
> > +/**
> > + * struct nand_ecc_caps - capability of ECC engine
> > + * @stepinfos: array of ECC step information
> > + * @nstepinfos: number of ECC step information
> > + * @calc_ecc_bytes: driver's hook to calculate ECC bytes per step
> > + */
> > +struct nand_ecc_caps {
> > + const struct nand_ecc_step_info *stepinfos;
> > + int nstepinfos;
> > + int (*calc_ecc_bytes)(struct nand_ecc_ctrl *ecc, int step_size,
> > + int strength);
> > +};
> > +
> > +/* a shorthand to generate struct nand_ecc_caps with only one ECC stepsize */
> > +#define NAND_ECC_CAPS_SINGLE(__name, __calc, __step, ...) \
> > +static const int __name##_strengths[] = { __VA_ARGS__ }; \
> > +static const struct nand_ecc_step_info __name##_stepinfo = { \
> > + .stepsize = __step, \
> > + .strengths = __name##_strengths, \
> > + .nstrengths = ARRAY_SIZE(__name##_strengths), \
> > +}; \
> > +static const struct nand_ecc_caps __name = { \
> > + .stepinfos = &__name##_stepinfo, \
> > + .nstepinfos = 1, \
> > + .calc_ecc_bytes = __calc, \
> > +}
> > +
> > +/**
> > * struct nand_sdr_timings - SDR NAND chip timings
> > *
> > * This struct defines the timing requirements of a SDR NAND chip.
>