From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751846AbeDDMnl (ORCPT ); Wed, 4 Apr 2018 08:43:41 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:41718 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751743AbeDDMni (ORCPT ); Wed, 4 Apr 2018 08:43:38 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3648C60F78 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=absahu@codeaurora.org From: Abhishek Sahu To: Boris Brezillon Cc: 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 , Abhishek Sahu Subject: [PATCH 8/9] mtd: nand: qcom: helper function for raw read Date: Wed, 4 Apr 2018 18:12:24 +0530 Message-Id: <1522845745-6624-9-git-send-email-absahu@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1522845745-6624-1-git-send-email-absahu@codeaurora.org> References: <1522845745-6624-1-git-send-email-absahu@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch does minor code reorganization for raw reads. Currently the raw read is required for complete page but for subsequent patches related with erased codeword bit flips detection, only few CW should be read. So, this patch adds helper function and introduces the read CW bitmask which specifies which CW reads are required in complete page. Signed-off-by: Abhishek Sahu --- drivers/mtd/nand/qcom_nandc.c | 186 +++++++++++++++++++++++++----------------- 1 file changed, 110 insertions(+), 76 deletions(-) diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c index 40c790e..f5d1fa4 100644 --- a/drivers/mtd/nand/qcom_nandc.c +++ b/drivers/mtd/nand/qcom_nandc.c @@ -1590,6 +1590,114 @@ static int check_flash_errors(struct qcom_nand_host *host, int cw_cnt) } /* + * Helper to perform the page raw read operation. The read_cw_mask will be + * used to specify the codewords for which the data should be read. The + * single page contains multiple CW. Sometime, only few CW data is required + * in complete page. Also, start address will be determined with + * this CW mask to skip unnecessary data copy from NAND flash device. Then, + * actual data copy from NAND controller to data buffer will be done only + * for the CWs which have the mask set. + */ +static int +nandc_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip, + u8 *data_buf, u8 *oob_buf, + int page, unsigned long read_cw_mask) +{ + struct qcom_nand_host *host = to_qcom_nand_host(chip); + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip); + struct nand_ecc_ctrl *ecc = &chip->ecc; + int i, ret; + int read_loc, start_step, last_step; + + nand_read_page_op(chip, page, 0, NULL, 0); + + host->use_ecc = false; + start_step = ffs(read_cw_mask) - 1; + last_step = fls(read_cw_mask); + + clear_bam_transaction(nandc); + set_address(host, host->cw_size * start_step, page); + update_rw_regs(host, last_step - start_step, true); + config_nand_page_read(nandc); + + for (i = start_step; i < last_step; i++) { + int data_size1, data_size2, oob_size1, oob_size2; + int reg_off = FLASH_BUF_ACC; + + data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1); + oob_size1 = host->bbm_size; + + if (i == (ecc->steps - 1)) { + data_size2 = ecc->size - data_size1 - + ((ecc->steps - 1) << 2); + oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw + + host->spare_bytes; + } else { + data_size2 = host->cw_data - data_size1; + oob_size2 = host->ecc_bytes_hw + host->spare_bytes; + } + + /* + * Don't perform actual data copy from NAND controller to data + * buffer through DMA for this codeword + */ + if (!(read_cw_mask & BIT(i))) { + if (nandc->props->is_bam) + nandc_set_read_loc(nandc, 0, 0, 0, 1); + + config_nand_cw_read(nandc, false); + + data_buf += data_size1 + data_size2; + oob_buf += oob_size1 + oob_size2; + + continue; + } + + if (nandc->props->is_bam) { + read_loc = 0; + nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0); + read_loc += data_size1; + + nandc_set_read_loc(nandc, 1, read_loc, oob_size1, 0); + read_loc += oob_size1; + + nandc_set_read_loc(nandc, 2, read_loc, data_size2, 0); + read_loc += data_size2; + + nandc_set_read_loc(nandc, 3, read_loc, oob_size2, 1); + } + + config_nand_cw_read(nandc, false); + + read_data_dma(nandc, reg_off, data_buf, data_size1, 0); + reg_off += data_size1; + data_buf += data_size1; + + read_data_dma(nandc, reg_off, oob_buf, oob_size1, 0); + reg_off += oob_size1; + oob_buf += oob_size1; + + read_data_dma(nandc, reg_off, data_buf, data_size2, 0); + reg_off += data_size2; + data_buf += data_size2; + + read_data_dma(nandc, reg_off, oob_buf, oob_size2, 0); + oob_buf += oob_size2; + } + + ret = submit_descs(nandc); + if (ret) + dev_err(nandc->dev, "failure to read raw page\n"); + + free_descs(nandc); + + if (!ret) + ret = check_flash_errors(host, last_step - start_step); + + return 0; +} + +/* * reads back status registers set by the controller to notify page read * errors. this is equivalent to what 'ecc->correct()' would do. */ @@ -1839,82 +1947,8 @@ static int qcom_nandc_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip, uint8_t *buf, int oob_required, int page) { - struct qcom_nand_host *host = to_qcom_nand_host(chip); - struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip); - u8 *data_buf, *oob_buf; - struct nand_ecc_ctrl *ecc = &chip->ecc; - int i, ret; - int read_loc; - - nand_read_page_op(chip, page, 0, NULL, 0); - data_buf = buf; - oob_buf = chip->oob_poi; - - host->use_ecc = false; - - clear_bam_transaction(nandc); - update_rw_regs(host, ecc->steps, true); - config_nand_page_read(nandc); - - for (i = 0; i < ecc->steps; i++) { - int data_size1, data_size2, oob_size1, oob_size2; - int reg_off = FLASH_BUF_ACC; - - data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1); - oob_size1 = host->bbm_size; - - if (i == (ecc->steps - 1)) { - data_size2 = ecc->size - data_size1 - - ((ecc->steps - 1) << 2); - oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw + - host->spare_bytes; - } else { - data_size2 = host->cw_data - data_size1; - oob_size2 = host->ecc_bytes_hw + host->spare_bytes; - } - - if (nandc->props->is_bam) { - read_loc = 0; - nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0); - read_loc += data_size1; - - nandc_set_read_loc(nandc, 1, read_loc, oob_size1, 0); - read_loc += oob_size1; - - nandc_set_read_loc(nandc, 2, read_loc, data_size2, 0); - read_loc += data_size2; - - nandc_set_read_loc(nandc, 3, read_loc, oob_size2, 1); - } - - config_nand_cw_read(nandc, false); - - read_data_dma(nandc, reg_off, data_buf, data_size1, 0); - reg_off += data_size1; - data_buf += data_size1; - - read_data_dma(nandc, reg_off, oob_buf, oob_size1, 0); - reg_off += oob_size1; - oob_buf += oob_size1; - - read_data_dma(nandc, reg_off, data_buf, data_size2, 0); - reg_off += data_size2; - data_buf += data_size2; - - read_data_dma(nandc, reg_off, oob_buf, oob_size2, 0); - oob_buf += oob_size2; - } - - ret = submit_descs(nandc); - if (ret) - dev_err(nandc->dev, "failure to read raw page\n"); - - free_descs(nandc); - - if (!ret) - ret = check_flash_errors(host, ecc->steps); - - return 0; + return nandc_read_page_raw(mtd, chip, buf, chip->oob_poi, page, + BIT(chip->ecc.steps) - 1); } /* implements ecc->read_oob() */ -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation