Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752091AbdHDHsY (ORCPT ); Fri, 4 Aug 2017 03:48:24 -0400 Received: from mail.free-electrons.com ([62.4.15.54]:50411 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751284AbdHDHsW (ORCPT ); Fri, 4 Aug 2017 03:48:22 -0400 Date: Fri, 4 Aug 2017 09:48:19 +0200 From: Boris Brezillon To: Abhishek Sahu Cc: dwmw2@infradead.org, computersforpeace@gmail.com, marek.vasut@gmail.com, richard@nod.at, cyrille.pitchen@wedev4u.fr, robh+dt@kernel.org, mark.rutland@arm.com, linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, andy.gross@linaro.org, architt@codeaurora.org, sricharan@codeaurora.org Subject: Re: [PATCH v2 07/25] mtd: nand: qcom: reorganize nand page read Message-ID: <20170804094819.78bd9208@bbrezillon> In-Reply-To: <1500464893-11352-8-git-send-email-absahu@codeaurora.org> References: <1500464893-11352-1-git-send-email-absahu@codeaurora.org> <1500464893-11352-8-git-send-email-absahu@codeaurora.org> X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4667 Lines: 135 On Wed, 19 Jul 2017 17:17:55 +0530 Abhishek Sahu wrote: > Each NAND page consist of multiple codewords. Following is > sequence for NAND page read according to hardware guide. > > 1. Program Power-up configuration, page row, page column > address and flash configuration registers. > 2. Write NAND_FLASH_CMD followed by NANC_EXEC_CMD for each > codeword. > 3. Read NAND_FLASH_STATUS for each codeword. > > The step 1 should be done once for each page and step 2,3 should > be done for each codeword. > > Currently, all the 3 steps are being done for each codeword which > is wrong. Now this patch reorganizes read page functions to > configure page specific register once and per codeword specific > registers for each NAND ECC step. Applied. Thanks, Boris > > Signed-off-by: Abhishek Sahu > --- > drivers/mtd/nand/qcom_nandc.c | 37 +++++++++++++++++++++++++++---------- > 1 file changed, 27 insertions(+), 10 deletions(-) > > diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c > index 110a26a..27ea594 100644 > --- a/drivers/mtd/nand/qcom_nandc.c > +++ b/drivers/mtd/nand/qcom_nandc.c > @@ -605,15 +605,23 @@ static int write_data_dma(struct qcom_nand_controller *nandc, int reg_off, > } > > /* > - * helper to prepare dma descriptors to configure registers needed for reading a > - * codeword/step in a page > + * Helper to prepare DMA descriptors for configuring registers > + * before reading a NAND page. > */ > -static void config_cw_read(struct qcom_nand_controller *nandc) > +static void config_nand_page_read(struct qcom_nand_controller *nandc) > { > - write_reg_dma(nandc, NAND_FLASH_CMD, 3); > + write_reg_dma(nandc, NAND_ADDR0, 2); > write_reg_dma(nandc, NAND_DEV0_CFG0, 3); > write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1); > +} > > +/* > + * Helper to prepare DMA descriptors for configuring registers > + * before reading each codeword in NAND page. > + */ > +static void config_nand_cw_read(struct qcom_nand_controller *nandc) > +{ > + write_reg_dma(nandc, NAND_FLASH_CMD, 1); > write_reg_dma(nandc, NAND_EXEC_CMD, 1); > > read_reg_dma(nandc, NAND_FLASH_STATUS, 2); > @@ -621,9 +629,15 @@ static void config_cw_read(struct qcom_nand_controller *nandc) > } > > /* > - * helpers to prepare dma descriptors used to configure registers needed for > - * writing a codeword/step in a page > + * Helper to prepare dma descriptors to configure registers needed for reading a > + * single codeword in page > */ > +static void config_nand_single_cw_page_read(struct qcom_nand_controller *nandc) > +{ > + config_nand_page_read(nandc); > + config_nand_cw_read(nandc); > +} > + > static void config_cw_write_pre(struct qcom_nand_controller *nandc) > { > write_reg_dma(nandc, NAND_FLASH_CMD, 3); > @@ -692,7 +706,7 @@ static int nandc_param(struct qcom_nand_host *host) > nandc->buf_count = 512; > memset(nandc->data_buffer, 0xff, nandc->buf_count); > > - config_cw_read(nandc); > + config_nand_single_cw_page_read(nandc); > > read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, > nandc->buf_count); > @@ -1105,6 +1119,8 @@ static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf, > struct nand_ecc_ctrl *ecc = &chip->ecc; > int i, ret; > > + config_nand_page_read(nandc); > + > /* queue cmd descs for each codeword */ > for (i = 0; i < ecc->steps; i++) { > int data_size, oob_size; > @@ -1118,7 +1134,7 @@ static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf, > oob_size = host->ecc_bytes_hw + host->spare_bytes; > } > > - config_cw_read(nandc); > + config_nand_cw_read(nandc); > > if (data_buf) > read_data_dma(nandc, FLASH_BUF_ACC, data_buf, > @@ -1178,7 +1194,7 @@ static int copy_last_cw(struct qcom_nand_host *host, int page) > set_address(host, host->cw_size * (ecc->steps - 1), page); > update_rw_regs(host, 1, true); > > - config_cw_read(nandc); > + config_nand_single_cw_page_read(nandc); > > read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, size); > > @@ -1228,6 +1244,7 @@ static int qcom_nandc_read_page_raw(struct mtd_info *mtd, > > host->use_ecc = false; > 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; > @@ -1246,7 +1263,7 @@ static int qcom_nandc_read_page_raw(struct mtd_info *mtd, > oob_size2 = host->ecc_bytes_hw + host->spare_bytes; > } > > - config_cw_read(nandc); > + config_nand_cw_read(nandc); > > read_data_dma(nandc, reg_off, data_buf, data_size1); > reg_off += data_size1;