From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 11 Apr 2018 20:57:57 +0200 From: Boris Brezillon To: Xiaolei Li Cc: , linux-mediatek@lists.infradead.org, linux-mtd@lists.infradead.org, srv_heupstream@mediatek.com Subject: Re: [PATCH 5/8] mtd: rawnand: Modify ->calc_ecc_bytes() hook in nand_ecc_caps Message-ID: <20180411205757.06495b7b@bbrezillon> In-Reply-To: <1523418118-57686-6-git-send-email-xiaolei.li@mediatek.com> References: <1523418118-57686-1-git-send-email-xiaolei.li@mediatek.com> <1523418118-57686-6-git-send-email-xiaolei.li@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 11 Apr 2018 11:41:55 +0800 Xiaolei Li 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)? > > Signed-off-by: Xiaolei Li > --- > 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.