From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753098AbdHKLkm (ORCPT ); Fri, 11 Aug 2017 07:40:42 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:55226 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753072AbdHKLki (ORCPT ); Fri, 11 Aug 2017 07:40:38 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 287DC60738 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@free-electrons.com Cc: dwmw2@infradead.org, computersforpeace@gmail.com, marek.vasut@gmail.com, richard@nod.at, cyrille.pitchen@wedev4u.fr, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, andy.gross@linaro.org, architt@codeaurora.org, sricharan@codeaurora.org, Abhishek Sahu Subject: [PATCH v4 10/20] mtd: nand: qcom: erased codeword detection configuration Date: Fri, 11 Aug 2017 17:09:25 +0530 Message-Id: <1502451575-15712-11-git-send-email-absahu@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1502451575-15712-1-git-send-email-absahu@codeaurora.org> References: <1502451575-15712-1-git-send-email-absahu@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The NAND controller returns ECC failure during read of completely erased codeword. The NAND controller has hardware functionality to detect erased codeword in case of BCH ECC algorithm. The NAND_ERASED_CW_DETECT_CFG register controls the erased codeword/page detection controller. This register should be reset before every page read by setting and clearing bit 0 of NAND_ERASED_CW_DETECT_CFG. Signed-off-by: Abhishek Sahu --- drivers/mtd/nand/qcom_nandc.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c index b452cfb..3d9fd7f 100644 --- a/drivers/mtd/nand/qcom_nandc.c +++ b/drivers/mtd/nand/qcom_nandc.c @@ -200,6 +200,11 @@ #define NAND_BAM_NWD BIT(1) /* Finish writing in the current sgl and start writing in another sgl */ #define NAND_BAM_NEXT_SGL BIT(2) +/* + * Erased codeword status is being used two times in single transfer so this + * flag will determine the current value of erased codeword status register + */ +#define NAND_ERASED_CW_SET BIT(4) /* * This data type corresponds to the BAM transaction which will be used for all @@ -278,6 +283,8 @@ struct nandc_regs { __le32 read_location2; __le32 read_location3; + __le32 erased_cw_detect_cfg_clr; + __le32 erased_cw_detect_cfg_set; }; /* @@ -805,6 +812,13 @@ static int write_reg_dma(struct qcom_nand_controller *nandc, int first, if (first == NAND_FLASH_CMD) flow_control = true; + if (first == NAND_ERASED_CW_DETECT_CFG) { + if (flags & NAND_ERASED_CW_SET) + vaddr = ®s->erased_cw_detect_cfg_set; + else + vaddr = ®s->erased_cw_detect_cfg_clr; + } + if (first == NAND_EXEC_CMD) flags |= NAND_BAM_NWD; @@ -857,6 +871,9 @@ static void config_nand_page_read(struct qcom_nand_controller *nandc) write_reg_dma(nandc, NAND_ADDR0, 2, 0); write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0); write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1, 0); + write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1, 0); + write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1, + NAND_ERASED_CW_SET | NAND_BAM_NEXT_SGL); } /* @@ -2258,6 +2275,10 @@ static int qcom_nand_host_setup(struct qcom_nand_host *host) host->clrflashstatus = FS_READY_BSY_N; host->clrreadstatus = 0xc0; + nandc->regs->erased_cw_detect_cfg_clr = + cpu_to_le32(CLR_ERASED_PAGE_DET); + nandc->regs->erased_cw_detect_cfg_set = + cpu_to_le32(SET_ERASED_PAGE_DET); dev_dbg(nandc->dev, "cfg0 %x cfg1 %x ecc_buf_cfg %x ecc_bch cfg %x cw_size %d cw_data %d strength %d parity_bytes %d steps %d\n", -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation