From mboxrd@z Thu Jan 1 00:00:00 1970 From: Abhishek Sahu Subject: Re: [PATCH v3 06/16] mtd: rawnand: qcom: use the ecc strength from device parameter Date: Mon, 28 May 2018 11:31:30 +0530 Message-ID: <85165cc27bb06fd7078dd04048d763ad@codeaurora.org> References: <1527250904-21988-1-git-send-email-absahu@codeaurora.org> <1527250904-21988-7-git-send-email-absahu@codeaurora.org> <20180526104305.6f957db9@xps13> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20180526104305.6f957db9@xps13> Sender: linux-kernel-owner@vger.kernel.org To: Miquel Raynal Cc: Boris Brezillon , David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Cyrille Pitchen , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, Andy Gross , Archit Taneja List-Id: linux-arm-msm@vger.kernel.org On 2018-05-26 14:13, Miquel Raynal wrote: > Hi Abhishek, > > On Fri, 25 May 2018 17:51:34 +0530, Abhishek Sahu > wrote: > >> Currently the driver uses the ECC strength specified in DT. >> The QPIC/EBI2 NAND supports 4 or 8-bit ECC correction. The same >> kind of board can have different NAND parts so use the ECC >> strength from device parameters if it is not specified in DT. >> >> Signed-off-by: Abhishek Sahu >> --- >> * Changes from v2: >> NONE > > Yes you did change things: > > - s/<< 2/* 4/ > - updated the cwperpage location > - the block handling the ecc-step-size property has been removed in a > previous patch > > Please be careful with that, it is time consuming to review the patches > all over again. > Sorry Miquel for that. I Will pay more attention to this. I can understand the effort require in reviewing and how this can help in making review quicker. >> >> * Changes from v1: >> >> 1. Removed the custom logic and used the helper fuction. >> >> drivers/mtd/nand/raw/qcom_nandc.c | 29 +++++++++++++++++++++-------- >> 1 file changed, 21 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c >> b/drivers/mtd/nand/raw/qcom_nandc.c >> index b538390..7377923 100644 >> --- a/drivers/mtd/nand/raw/qcom_nandc.c >> +++ b/drivers/mtd/nand/raw/qcom_nandc.c >> @@ -2315,19 +2315,39 @@ static int qcom_nand_ooblayout_free(struct >> mtd_info *mtd, int section, >> .free = qcom_nand_ooblayout_free, >> }; >> >> +static int >> +qcom_nandc_calc_ecc_bytes(int step_size, int strength) >> +{ >> + return strength == 4 ? 12 : 16; >> +} >> +NAND_ECC_CAPS_SINGLE(qcom_nandc_ecc_caps, qcom_nandc_calc_ecc_bytes, >> + NANDC_STEP_SIZE, 4, 8); >> + >> static int qcom_nand_host_setup(struct qcom_nand_host *host) >> { >> struct nand_chip *chip = &host->chip; >> struct mtd_info *mtd = nand_to_mtd(chip); >> struct nand_ecc_ctrl *ecc = &chip->ecc; >> struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip); >> - int cwperpage, bad_block_byte; >> + int cwperpage, bad_block_byte, ret; >> bool wide_bus; >> int ecc_mode = 1; >> >> /* controller only supports 512 bytes of data in each step */ >> ecc->size = NANDC_STEP_SIZE; >> wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false; >> + cwperpage = mtd->writesize / NANDC_STEP_SIZE; >> + >> + /* >> + * Each CW has 4 available OOB bytes which will be protected with >> ECC >> + * so remaining bytes can be used for ECC. >> + */ >> + ret = nand_ecc_choose_conf(chip, &qcom_nandc_ecc_caps, >> + mtd->oobsize - cwperpage * 4); > > Nitpick: could you add parenthesis around (cwperpage * 4) just for > clarity. > Thanks Miquel. I will update that. Regards, Abhishek >> + if (ret) { >> + dev_err(nandc->dev, "No valid ECC settings possible\n"); >> + return ret; >> + } >> >> if (ecc->strength >= 8) { >> /* 8 bit ECC defaults to BCH ECC on all platforms */ >> @@ -2396,7 +2416,6 @@ static int qcom_nand_host_setup(struct >> qcom_nand_host *host) >> >> mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops); >> >> - cwperpage = mtd->writesize / ecc->size; >> nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage, >> cwperpage); >> >> @@ -2412,12 +2431,6 @@ static int qcom_nand_host_setup(struct >> qcom_nand_host *host) >> * for 8 bit ECC >> */ >> host->cw_size = host->cw_data + ecc->bytes; >> - >> - if (ecc->bytes * (mtd->writesize / ecc->size) > mtd->oobsize) { >> - dev_err(nandc->dev, "ecc data doesn't fit in OOB area\n"); >> - return -EINVAL; >> - } >> - >> bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + >> 1; >> >> host->cfg0 = (cwperpage - 1) << CW_PER_PAGE > > Once corrected: > > Acked-by: Miquel Raynal > > Thanks, > Miquèl