From patchwork Wed Feb 26 10:23:13 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: pekon gupta X-Patchwork-Id: 324255 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:770:15f::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id F2BEE2C009B for ; Wed, 26 Feb 2014 21:24:58 +1100 (EST) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WIbfG-0006oO-Lz; Wed, 26 Feb 2014 10:24:35 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WIbf5-0001E8-LI; Wed, 26 Feb 2014 10:24:23 +0000 Received: from devils.ext.ti.com ([198.47.26.153]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WIber-0001Aq-D4 for linux-mtd@lists.infradead.org; Wed, 26 Feb 2014 10:24:11 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id s1QANhdn032604; Wed, 26 Feb 2014 04:23:43 -0600 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id s1QANhQB029597; Wed, 26 Feb 2014 04:23:43 -0600 Received: from dflp33.itg.ti.com (10.64.6.16) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.174.1; Wed, 26 Feb 2014 04:23:43 -0600 Received: from psplinux063.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id s1QANYi4029477; Wed, 26 Feb 2014 04:23:41 -0600 From: Pekon Gupta To: Brian Norris Subject: [PATCH v6 3/4] mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch4 in omap_calculate_ecc_bch Date: Wed, 26 Feb 2014 15:53:13 +0530 Message-ID: <1393410194-15094-4-git-send-email-pekon@ti.com> X-Mailer: git-send-email 1.8.5.1.163.gd7aced9 In-Reply-To: <1393410194-15094-1-git-send-email-pekon@ti.com> References: <1393410194-15094-1-git-send-email-pekon@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140226_052409_609926_BF180D1E X-CRM114-Status: GOOD ( 15.25 ) X-Spam-Score: -6.9 (------) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-6.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [198.47.26.153 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Stefan Roese , linux-mtd , Pekon Gupta , Artem Bityutskiy X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org merges omap3_calculate_ecc_bch4() into omap_calculate_ecc_bch() so that common callback can be used for both OMAP_ECC_BCH4_CODE_HW and OMAP_ECC_BCH4_CODE_HW_DETECTION_SW ecc-schemes +---------------------+-------------------------------------------------------+ |ecc-scheme | nand_chip->calculate() after this patch | +---------------------+-------------------------------------------------------+ |HAM1_ECC | omap_calculate_ecc() | +---------------------+-------------------------------------------------------+ |BCH4_HW_DETECTION_SW | omap3_calculate_ecc_bch4() -> omap_calculate_ecc_bch()| |BCH4_HW | omap_calculate_ecc_bch() | |BCH8_HW_DETECTION_SW | omap3_calculate_ecc_bch8() | |BCH8_HW | omap_calculate_ecc_bch() | +---------------------+-------------------------------------------------------+ Tested-by: Stefan Roese Signed-off-by: Pekon Gupta --- drivers/mtd/nand/omap2.c | 51 ++++++++++-------------------------------------- 1 file changed, 10 insertions(+), 41 deletions(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index f1a33eb..bcc7ecc1 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -1116,48 +1116,10 @@ static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode) writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control); } #endif +static u8 bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f}; #ifdef CONFIG_MTD_NAND_ECC_BCH /** - * omap3_calculate_ecc_bch4 - Generate 7 bytes of ECC bytes - * @mtd: MTD device structure - * @dat: The pointer to data on which ecc is computed - * @ecc_code: The ecc_code buffer - */ -static int omap3_calculate_ecc_bch4(struct mtd_info *mtd, const u_char *dat, - u_char *ecc_code) -{ - struct omap_nand_info *info = container_of(mtd, struct omap_nand_info, - mtd); - unsigned long nsectors, val1, val2; - int i; - - nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1; - - for (i = 0; i < nsectors; i++) { - - /* Read hw-computed remainder */ - val1 = readl(info->reg.gpmc_bch_result0[i]); - val2 = readl(info->reg.gpmc_bch_result1[i]); - - /* - * Add constant polynomial to remainder, in order to get an ecc - * sequence of 0xFFs for a buffer filled with 0xFFs; and - * left-justify the resulting polynomial. - */ - *ecc_code++ = 0x28 ^ ((val2 >> 12) & 0xFF); - *ecc_code++ = 0x13 ^ ((val2 >> 4) & 0xFF); - *ecc_code++ = 0xcc ^ (((val2 & 0xF) << 4)|((val1 >> 28) & 0xF)); - *ecc_code++ = 0x39 ^ ((val1 >> 20) & 0xFF); - *ecc_code++ = 0x96 ^ ((val1 >> 12) & 0xFF); - *ecc_code++ = 0xac ^ ((val1 >> 4) & 0xFF); - *ecc_code++ = 0x7f ^ ((val1 & 0xF) << 4); - } - - return 0; -} - -/** * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes * @mtd: MTD device structure * @dat: The pointer to data on which ecc is computed @@ -1204,7 +1166,6 @@ static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat, } #endif /* CONFIG_MTD_NAND_ECC_BCH */ -#ifdef CONFIG_MTD_NAND_OMAP_BCH /** * omap_calculate_ecc_bch - Generate bytes of ECC bytes * @mtd: MTD device structure @@ -1247,6 +1208,7 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, *ecc_code++ = ((bch_val1 >> 8) & 0xFF); *ecc_code++ = (bch_val1 & 0xFF); break; + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: case OMAP_ECC_BCH4_CODE_HW: bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]); bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]); @@ -1265,6 +1227,12 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, /* ECC scheme specific syndrome customizations */ switch (info->ecc_opt) { + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: + /* Add constant polynomial to remainder, so that + * ECC of blank pages results in 0x0 on reading back */ + for (i = 0; i < eccbytes; i++) + ecc_calc[i] ^= bch4_polynomial[i]; + break; case OMAP_ECC_BCH4_CODE_HW: /* Set 8th ECC byte as 0x0 for ROM compatibility */ ecc_calc[eccbytes - 1] = 0x0; @@ -1307,6 +1275,7 @@ static int count_zero_bits(u_char *buf, int length, return 0; } +#ifdef CONFIG_MTD_NAND_OMAP_BCH /** * omap_elm_correct_data - corrects page data area in case error reported * @mtd: MTD device structure @@ -1841,7 +1810,7 @@ static int omap_nand_probe(struct platform_device *pdev) nand_chip->ecc.strength = 4; nand_chip->ecc.hwctl = omap3_enable_hwecc_bch; nand_chip->ecc.correct = nand_bch_correct_data; - nand_chip->ecc.calculate = omap3_calculate_ecc_bch4; + nand_chip->ecc.calculate = omap_calculate_ecc_bch; /* define ECC layout */ ecclayout->eccbytes = nand_chip->ecc.bytes * (mtd->writesize /