From patchwork Sat Jul 13 20:54:50 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: pekon gupta X-Patchwork-Id: 2827194 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4E40BC0AB2 for ; Sat, 13 Jul 2013 20:56:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CF64920122 for ; Sat, 13 Jul 2013 20:55:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 38EE720116 for ; Sat, 13 Jul 2013 20:55:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751341Ab3GMUz5 (ORCPT ); Sat, 13 Jul 2013 16:55:57 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:33951 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751221Ab3GMUz4 (ORCPT ); Sat, 13 Jul 2013 16:55:56 -0400 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6DKtHLH015446; Sat, 13 Jul 2013 15:55:17 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6DKtHGj008187; Sat, 13 Jul 2013 15:55:17 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Sat, 13 Jul 2013 15:55:16 -0500 Received: from psplinux064.india.ti.com (psplinux064.india.ti.com [10.24.100.118]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6DKt1Sq012200; Sat, 13 Jul 2013 15:55:13 -0500 From: Pekon Gupta To: , , , , CC: , , , , , , , Pekon Gupta Subject: [PATCH v5 3/4] mtd:nand:omap2: updated support for BCH4 ECC scheme Date: Sun, 14 Jul 2013 02:24:50 +0530 Message-ID: <1373748891-7779-4-git-send-email-pekon@ti.com> X-Mailer: git-send-email 1.8.1 In-Reply-To: <1373748891-7779-1-git-send-email-pekon@ti.com> References: <1373748891-7779-1-git-send-email-pekon@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds following two flavours of BCH4 ECC scheme in omap2-nand driver - OMAP_ECC_BCH4_CODE_HW_DETECTION_SW - uses GPMC H/W engine for calculating ECC. - uses software library (lib/bch.h & nand_bch.h) for error correction. - OMAP_ECC_BCH4_CODE_HW - uses GPMC H/W engine for calculating ECC. - uses ELM H/W engine for error correction. With this patch omap2-nand driver supports following ECC schemes: +---------------------------------------+---------------+---------------+ | ECC scheme |ECC calculation|Error detection| +---------------------------------------+---------------+---------------+ |OMAP_ECC_HAMMING_CODE_DEFAULT |S/W |S/W | |OMAP_ECC_HAMMING_CODE_HW |H/W (GPMC) |S/W | |OMAP_ECC_HAMMING_CODE_HW_ROMCODE |H/W (GPMC) |S/W | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH4_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| |OMAP_ECC_BCH4_CODE_HW |H/W (GPMC) |H/W (ELM) | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W (lib/bch.h)| |OMAP_ECC_BCH8_CODE_HW |H/W (GPMC) |H/W (ELM) | +---------------------------------------+---------------+---------------+ Important: - Selection of OMAP_ECC_BCHx_CODE_HW_DETECTION_SW requires, Kconfig: CONFIG_MTD_NAND_ECC_BCH: enables S/W based BCH ECC algorithm. - Selection of OMAP_ECC_BCHx_CODE_HW requires, Kconfig: CONFIG_MTD_NAND_OMAP_BCH: enables ELM H/W module. Signed-off-by: Pekon Gupta --- .../devicetree/bindings/mtd/gpmc-nand.txt | 27 +++- drivers/mtd/nand/Kconfig | 30 +--- drivers/mtd/nand/omap2.c | 168 +++++++++------------ include/linux/platform_data/mtd-nand-omap2.h | 10 +- 4 files changed, 102 insertions(+), 133 deletions(-) diff --git a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt index c6551b6..d307c67 100644 --- a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt +++ b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt @@ -28,26 +28,43 @@ Optional properties: "hamming_code_sw" 1-bit Hamming ECC - ECC calculation in software - Error detection in software + - ECC layout compatible with S/W scheme "hamming_code_hw" 1-bit Hamming ECC - ECC calculation in hardware - Error detection in software + - ECC layout compatible with S/W scheme "hamming_code_hw_romcode" 1-bit Hamming ECC - ECC calculation in hardware - Error detection in software - - ECC layout compatible to ROM code + - ECC layout compatible with ROM code - "bch8_hw_code_detection_sw" 8-bit BCH ECC + "bch4_code_hw_detection_sw" 4-bit BCH ECC - ECC calculation in hardware - Error detection in software - - depends on CONFIG_MTD_NAND_ECC_BCH + - ECC layout compatible with S/W scheme + * depends on CONFIG_MTD_NAND_ECC_BCH + + "bch4_code_hw" 4-bit BCH ECC + - ECC calculation in hardware + - Error detection in hardware + - ECC layout compatible with ROM code + * depends on CONFIG_MTD_NAND_OMAP_BCH + * requires to be specified + + "bch8_code_hw_detection_sw" 8-bit BCH ECC + - ECC calculation in hardware + - Error detection in software + - ECC layout compatible with S/W scheme + * depends on CONFIG_MTD_NAND_ECC_BCH "bch8_code_hw" 8-bit BCH ECC - ECC calculation in hardware - Error detection in hardware - - depends on CONFIG_MTD_NAND_OMAP_BCH - - requires to be specified + - ECC layout compatible with ROM code + * depends on CONFIG_MTD_NAND_OMAP_BCH + * requires to be specified - elm_id: Specifies elm device node. This is required to diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 5ef8f5e..64830f9 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -95,35 +95,13 @@ config MTD_NAND_OMAP2 config MTD_NAND_OMAP_BCH depends on MTD_NAND && MTD_NAND_OMAP2 && ARCH_OMAP3 - tristate "Enable support for hardware BCH error correction" + tristate "Support hardware based BCH error correction" default n select BCH - select BCH_CONST_PARAMS help - Support for hardware BCH error correction. - -choice - prompt "BCH error correction capability" - depends on MTD_NAND_OMAP_BCH - -config MTD_NAND_OMAP_BCH8 - bool "8 bits / 512 bytes (recommended)" - help - Support correcting up to 8 bitflips per 512-byte block. - This will use 13 bytes of spare area per 512 bytes of page data. - This is the recommended mode, as 4-bit mode does not work - on some OMAP3 revisions, due to a hardware bug. - -config MTD_NAND_OMAP_BCH4 - bool "4 bits / 512 bytes" - help - Support correcting up to 4 bitflips per 512-byte block. - This will use 7 bytes of spare area per 512 bytes of page data. - Note that this mode does not work on some OMAP3 revisions, due to a - hardware bug. Please check your OMAP datasheet before selecting this - mode. - -endchoice + Some devices have built-in ELM hardware engine, which can be used to + locate and correct errors when using BCH ECC scheme. This enables the + driver support for same. if MTD_NAND_OMAP_BCH config BCH_CONST_M diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index ea857cc..e9ef743 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -27,6 +27,7 @@ #ifdef CONFIG_MTD_NAND_ECC_BCH #include +#include #endif #ifdef CONFIG_MTD_NAND_OMAP_BCH #include @@ -144,7 +145,6 @@ #define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */ #define BADBLOCK_MARKER_LENGTH 0x2 -#define OMAP_ECC_BCH8_POLYNOMIAL 0x201b #ifdef CONFIG_MTD_NAND_OMAP_BCH static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, @@ -185,10 +185,9 @@ struct omap_nand_info { OMAP_NAND_IO_WRITE, /* write */ } iomode; u_char *buf; - int buf_len; + int buf_len; struct gpmc_nand_regs reg; /* fields specific for BCHx_HW ECC scheme */ - struct bch_control *bch; bool is_elm_used; struct device *elm_dev; struct device_node *of_node; @@ -1227,58 +1226,6 @@ static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat, return 0; } -/** - * omap3_correct_data_bch - Decode received data and correct errors - * @mtd: MTD device structure - * @data: page data - * @read_ecc: ecc read from nand flash - * @calc_ecc: ecc read from HW ECC registers - */ -static int omap3_correct_data_bch(struct mtd_info *mtd, u_char *data, - u_char *read_ecc, u_char *calc_ecc) -{ - int i, count; - /* cannot correct more than 8 errors */ - unsigned int errloc[8]; - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - - count = decode_bch(info->bch, NULL, 512, read_ecc, calc_ecc, NULL, - errloc); - if (count > 0) { - /* correct errors */ - for (i = 0; i < count; i++) { - /* correct data only, not ecc bytes */ - if (errloc[i] < 8*512) - data[errloc[i]/8] ^= 1 << (errloc[i] & 7); - pr_debug("corrected bitflip %u\n", errloc[i]); - } - } else if (count < 0) { - pr_err("ecc unrecoverable error\n"); - } - return count; -} - -/** - * omap3_free_bch - Release BCH ecc resources - * @mtd: MTD device structure - */ -static void omap3_free_bch(struct mtd_info *mtd) -{ - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - if (info->bch) { - free_bch(info->bch); - info->bch = NULL; - } -} - -#else - -static void omap3_free_bch(struct mtd_info *mtd) -{ -} - #endif /* CONFIG_MTD_NAND_ECC_BCH */ @@ -1730,13 +1677,13 @@ static int omap_nand_probe(struct platform_device *pdev) info->pdev = pdev; info->gpmc_cs = pdata->cs; info->reg = pdata->reg; - info->bch = NULL; info->nand.options = NAND_BUSWIDTH_AUTO; info->nand.options |= NAND_SKIP_BBTSCAN; #ifdef CONFIG_MTD_NAND_OMAP_BCH info->of_node = pdata->of_node; #endif + info->nand.ecc.priv = NULL; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (res == NULL) { @@ -1933,21 +1880,43 @@ static int omap_nand_probe(struct platform_device *pdev) omap_oobinfo.eccbytes; goto custom_ecc_layout; +#ifdef CONFIG_MTD_NAND_ECC_BCH + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: + pr_info("using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW ECC scheme"); + info->nand.ecc.mode = NAND_ECC_HW; + info->nand.ecc.size = 512; + info->nand.ecc.bytes = 7; + info->nand.ecc.strength = 4; + info->nand.ecc.hwctl = omap3_enable_hwecc_bch; + info->nand.ecc.correct = nand_bch_correct_data; + info->nand.ecc.calculate = omap3_calculate_ecc_bch4; + /* software bch library is used for locating errors */ + info->nand.ecc.priv = nand_bch_init(mtd, + info->nand.ecc.size, + info->nand.ecc.bytes, + &info->nand.ecc.layout); + if (!info->nand.ecc.priv) { + pr_err("unable initialize S/W BCH logic\n"); + err = -EINVAL; + goto out_release_mem_region; + } + goto generic_ecc_layout; +#endif #ifdef CONFIG_MTD_NAND_OMAP_BCH - case OMAP_ECC_BCH8_CODE_HW: - pr_info("using OMAP_ECC_BCH8_CODE_HW ECC scheme\n"); + case OMAP_ECC_BCH4_CODE_HW: + pr_info("using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); info->nand.ecc.mode = NAND_ECC_HW; info->nand.ecc.size = 512; - /* 14th bit is kept reserved for ROM-code compatibility */ - info->nand.ecc.bytes = 13 + 1; - info->nand.ecc.strength = 8; + /* 8th bit is kept reserved for ROM-code compatibility */ + info->nand.ecc.bytes = 7 + 1; + info->nand.ecc.strength = 4; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; info->nand.ecc.correct = omap_elm_correct_data; info->nand.ecc.calculate = omap3_calculate_ecc_bch; info->nand.ecc.read_page = omap_read_page_bch; info->nand.ecc.write_page = omap_write_page_bch; - /* This ECC scheme requires ELM H/W block */ - if (is_elm_present(info, BCH8_ECC) < 0) { + /* ELM H/W engine is used for locating errors */ + if (is_elm_present(info, BCH4_ECC) < 0) { pr_err("ELM module not detected, required for ECC\n"); err = -EINVAL; goto out_release_mem_region; @@ -1969,51 +1938,46 @@ static int omap_nand_probe(struct platform_device *pdev) info->nand.ecc.bytes = 13; info->nand.ecc.strength = 8; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; - info->nand.ecc.correct = omap3_correct_data_bch; + info->nand.ecc.correct = nand_bch_correct_data; info->nand.ecc.calculate = omap3_calculate_ecc_bch8; - /* define custom ECC layout */ - omap_oobinfo.eccbytes = info->nand.ecc.bytes * - (mtd->writesize / - info->nand.ecc.size); - omap_oobinfo.eccpos[0] = info->mtd.oobsize - - omap_oobinfo.eccbytes; - omap_oobinfo.oobfree->offset = BADBLOCK_MARKER_LENGTH; /* software bch library is used for locating errors */ - info->bch = init_bch(info->nand.ecc.bytes, - info->nand.ecc.strength, - OMAP_ECC_BCH8_POLYNOMIAL); - if (!info->bch) { + info->nand.ecc.priv = nand_bch_init(mtd, + info->nand.ecc.size, + info->nand.ecc.bytes, + &info->nand.ecc.layout); + if (!info->nand.ecc.priv) { pr_err("unable initialize S/W BCH logic\n"); err = -EINVAL; goto out_release_mem_region; } - goto custom_ecc_layout; - - case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: - pr_info("using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW ECC\n"); + goto generic_ecc_layout; +#endif +#ifdef CONFIG_MTD_NAND_OMAP_BCH + case OMAP_ECC_BCH8_CODE_HW: + pr_info("using OMAP_ECC_BCH8_CODE_HW ECC scheme\n"); info->nand.ecc.mode = NAND_ECC_HW; info->nand.ecc.size = 512; - info->nand.ecc.bytes = 7; - info->nand.ecc.strength = 4; + /* 14th bit is kept reserved for ROM-code compatibility */ + info->nand.ecc.bytes = 13 + 1; + info->nand.ecc.strength = 8; info->nand.ecc.hwctl = omap3_enable_hwecc_bch; - info->nand.ecc.correct = omap3_correct_data_bch; - info->nand.ecc.calculate = omap3_calculate_ecc_bch4; + info->nand.ecc.correct = omap_elm_correct_data; + info->nand.ecc.calculate = omap3_calculate_ecc_bch; + info->nand.ecc.read_page = omap_read_page_bch; + info->nand.ecc.write_page = omap_write_page_bch; + /* ELM H/W engine is used for locating errors */ + if (is_elm_present(info, BCH8_ECC) < 0) { + pr_err("ELM module not detected, required for ECC\n"); + err = -EINVAL; + goto out_release_mem_region; + } /* define custom ECC layout */ omap_oobinfo.eccbytes = info->nand.ecc.bytes * (mtd->writesize / info->nand.ecc.size); - omap_oobinfo.eccpos[0] = info->mtd.oobsize - + omap_oobinfo.eccpos[0] = BADBLOCK_MARKER_LENGTH; + omap_oobinfo.oobfree->offset = omap_oobinfo.eccpos[0] + omap_oobinfo.eccbytes; - omap_oobinfo.oobfree->offset = BADBLOCK_MARKER_LENGTH; - /* software bch library is used for locating errors */ - info->bch = init_bch(info->nand.ecc.bytes, - info->nand.ecc.strength, - OMAP_ECC_BCH8_POLYNOMIAL); - if (!info->bch) { - pr_err("unable initialize S/W BCH logic\n"); - err = -EINVAL; - goto out_release_mem_region; - } goto custom_ecc_layout; #endif default: @@ -2065,8 +2029,14 @@ out_release_mem_region: if (info->gpmc_irq_fifo > 0) free_irq(info->gpmc_irq_fifo, info); release_mem_region(info->phys_base, info->mem_size); + out_free_info: - omap3_free_bch(&info->mtd); +#ifdef CONFIG_MTD_NAND_ECC_BCH + if (info->nand.ecc.priv) { + nand_bch_free(info->nand.ecc.priv); + info->nand.ecc.priv = NULL; + } +#endif kfree(info); return err; @@ -2078,8 +2048,12 @@ static int omap_nand_remove(struct platform_device *pdev) struct mtd_info *mtd = platform_get_drvdata(pdev); struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, mtd); - omap3_free_bch(&info->mtd); - +#ifdef CONFIG_MTD_NAND_ECC_BCH + if (info->nand.ecc.priv) { + nand_bch_free(info->nand.ecc.priv); + info->nand.ecc.priv = NULL; + } +#endif if (info->dma) dma_release_channel(info->dma); diff --git a/include/linux/platform_data/mtd-nand-omap2.h b/include/linux/platform_data/mtd-nand-omap2.h index ce74576..9fcee61 100644 --- a/include/linux/platform_data/mtd-nand-omap2.h +++ b/include/linux/platform_data/mtd-nand-omap2.h @@ -30,14 +30,14 @@ enum omap_ecc { /* 1-bit ECC calculation by GPMC, Error detection by Software */ /* ECC layout compatible to legacy ROMCODE. */ OMAP_ECC_HAMMING_CODE_HW_ROMCODE, - /* 4-bit ECC calculation by GPMC, Error detection by ELM */ - OMAP_ECC_BCH4_CODE_HW, /* 4-bit ECC calculation by GPMC, Error detection by Software */ OMAP_ECC_BCH4_CODE_HW_DETECTION_SW, - /* 8-bit ECC calculation by GPMC, Error detection by ELM */ - OMAP_ECC_BCH8_CODE_HW, + /* 4-bit ECC calculation by GPMC, Error detection by ELM */ + OMAP_ECC_BCH4_CODE_HW, /* 8-bit ECC calculation by GPMC, Error detection by Software */ - OMAP_ECC_BCH8_CODE_HW_DETECTION_SW + OMAP_ECC_BCH8_CODE_HW_DETECTION_SW, + /* 8-bit ECC calculation by GPMC, Error detection by ELM */ + OMAP_ECC_BCH8_CODE_HW }; struct gpmc_nand_regs {