From patchwork Tue Oct 15 05:49:50 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: pekon gupta X-Patchwork-Id: 3043461 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 47CBFBF924 for ; Tue, 15 Oct 2013 05:51:25 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3F3522016C for ; Tue, 15 Oct 2013 05:51:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1637220173 for ; Tue, 15 Oct 2013 05:51:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932829Ab3JOFvV (ORCPT ); Tue, 15 Oct 2013 01:51:21 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:35571 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932512Ab3JOFvQ (ORCPT ); Tue, 15 Oct 2013 01:51:16 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id r9F5oYMx029480; Tue, 15 Oct 2013 00:50:34 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id r9F5oYgx020689; Tue, 15 Oct 2013 00:50:34 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.2.342.3; Tue, 15 Oct 2013 00:50:34 -0500 Received: from psplinux063.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id r9F5oHYX016248; Tue, 15 Oct 2013 00:50:29 -0500 From: Pekon Gupta To: , , , , , CC: , , , , , , , , , , , Pekon Gupta Subject: [PATCH v9 2/9] ARM: OMAP2+: cleaned-up DT support of various ECC schemes Date: Tue, 15 Oct 2013 11:19:50 +0530 Message-ID: <1381816197-20477-3-git-send-email-pekon@ti.com> X-Mailer: git-send-email 1.8.1 In-Reply-To: <1381816197-20477-1-git-send-email-pekon@ti.com> References: <1381816197-20477-1-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=-4.4 required=5.0 tests=BAYES_00,KHOP_BIG_TO_CC, RCVD_IN_DNSWL_HI, 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 OMAP NAND driver support multiple ECC scheme, which can used in different flavours, depending on in-build Hardware engines present on SoC. This patch updates following in DT bindings related to sectionion of ecc-schemes - ti,elm-id: replaces elm_id (maintains backward compatibility) - ti,nand-ecc-opts: selection of h/w or s/w implementation of an ecc-scheme depends on ti,elm-id. (supported values ham1, bch4, and bch8) - maintain backward compatibility to deprecated DT bindings (sw, hw, hw-romcode) Below table shows different flavours of ecc-schemes supported by OMAP devices +---------------------------------------+---------------+---------------+ | ECC scheme |ECC calculation|Error detection| +---------------------------------------+---------------+---------------+ |OMAP_ECC_HAM1_CODE_HW |H/W (GPMC) |S/W | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH8_CODE_HW_DETECTION_SW |H/W (GPMC) |S/W | |(requires CONFIG_MTD_NAND_ECC_BCH) | | | +---------------------------------------+---------------+---------------+ |OMAP_ECC_BCH8_CODE_HW |H/W (GPMC) |H/W (ELM) | |(requires CONFIG_MTD_NAND_OMAP_BCH && | | | | ti,elm-id in DT) | | | +---------------------------------------+---------------+---------------+ To optimize footprint of omap2-nand driver, selection of some ECC schemes also require enabling following Kconfigs, in addition to setting appropriate DT bindings - Kconfig:CONFIG_MTD_NAND_ECC_BCH error detection done in software - Kconfig:CONFIG_MTD_NAND_OMAP_BCH error detection done by h/w engine Signed-off-by: Pekon Gupta Reviewed-by: Felipe Balbi Acked-by: Tony Lindgren --- .../devicetree/bindings/mtd/gpmc-nand.txt | 8 +++- arch/arm/mach-omap2/gpmc.c | 45 ++++++++++++++++------ include/linux/platform_data/mtd-nand-omap2.h | 14 +++++-- 3 files changed, 50 insertions(+), 17 deletions(-) diff --git a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt index 25ee232..5e1f31b 100644 --- a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt +++ b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt @@ -36,8 +36,12 @@ Optional properties: "prefetch-dma" Prefetch enabled sDMA mode "prefetch-irq" Prefetch enabled irq mode - - elm_id: Specifies elm device node. This is required to support BCH - error correction using ELM module. + - elm_id: use "ti,elm-id" instead + - ti,elm-id: Specifies phandle of the ELM devicetree node. + ELM is an on-chip hardware engine on TI SoC which is used for + locating ECC errors for BCHx algorithms. SoC devices which have + ELM hardware engines should specify this device node in .dtsi + Using ELM for ECC error correction frees some CPU cycles. For inline partiton table parsing (optional): diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c index c9fb353..9473c9f 100644 --- a/arch/arm/mach-omap2/gpmc.c +++ b/arch/arm/mach-omap2/gpmc.c @@ -1341,12 +1341,6 @@ static void __maybe_unused gpmc_read_timings_dt(struct device_node *np, #ifdef CONFIG_MTD_NAND -static const char * const nand_ecc_opts[] = { - [OMAP_ECC_HAM1_CODE_HW] = "ham1", - [OMAP_ECC_BCH4_CODE_HW] = "bch4", - [OMAP_ECC_BCH8_CODE_HW] = "bch8", -}; - static const char * const nand_xfer_types[] = { [NAND_OMAP_PREFETCH_POLLED] = "prefetch-polled", [NAND_OMAP_POLLED] = "polled", @@ -1376,12 +1370,39 @@ static int gpmc_probe_nand_child(struct platform_device *pdev, gpmc_nand_data->cs = val; gpmc_nand_data->of_node = child; - if (!of_property_read_string(child, "ti,nand-ecc-opt", &s)) - for (val = 0; val < ARRAY_SIZE(nand_ecc_opts); val++) - if (!strcasecmp(s, nand_ecc_opts[val])) { - gpmc_nand_data->ecc_opt = val; - break; - } + /* Detect availability of ELM module */ + gpmc_nand_data->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0); + if (gpmc_nand_data->elm_of_node == NULL) + gpmc_nand_data->elm_of_node = + of_parse_phandle(child, "elm_id", 0); + if (gpmc_nand_data->elm_of_node == NULL) + pr_warn("%s: ti,elm-id property not found\n", __func__); + + /* select NAND ecc-opt */ + if (of_property_read_string(child, "ti,nand-ecc-opt", &s)) { + pr_err("%s: ti,nand-ecc-opt not found\n", __func__); + return -ENODEV; + } + if (!strcmp(s, "ham1") || !strcmp(s, "sw") || + !strcmp(s, "hw") || !strcmp(s, "hw-romcode")) + gpmc_nand_data->ecc_opt = + OMAP_ECC_HAM1_CODE_HW; + else if (!strcmp(s, "bch4")) + if (gpmc_nand_data->elm_of_node) + gpmc_nand_data->ecc_opt = + OMAP_ECC_BCH4_CODE_HW; + else + gpmc_nand_data->ecc_opt = + OMAP_ECC_BCH4_CODE_HW_DETECTION_SW; + else if (!strcmp(s, "bch8")) + if (gpmc_nand_data->elm_of_node) + gpmc_nand_data->ecc_opt = + OMAP_ECC_BCH8_CODE_HW; + else + gpmc_nand_data->ecc_opt = + OMAP_ECC_BCH8_CODE_HW_DETECTION_SW; + else + pr_err("%s: ti,nand-ecc-opt invalid value\n", __func__); if (!of_property_read_string(child, "ti,nand-xfer-type", &s)) for (val = 0; val < ARRAY_SIZE(nand_xfer_types); val++) diff --git a/include/linux/platform_data/mtd-nand-omap2.h b/include/linux/platform_data/mtd-nand-omap2.h index cb5a54a..4da5bfa 100644 --- a/include/linux/platform_data/mtd-nand-omap2.h +++ b/include/linux/platform_data/mtd-nand-omap2.h @@ -23,9 +23,16 @@ enum nand_io { }; enum omap_ecc { - OMAP_ECC_HAM1_CODE_HW = 0, /* 1-bit Hamming ecc code */ - OMAP_ECC_BCH4_CODE_HW, /* 4-bit BCH ecc code */ - OMAP_ECC_BCH8_CODE_HW, /* 8-bit BCH ecc code */ + /* 1-bit ECC calculation by GPMC, Error detection by Software */ + OMAP_ECC_HAM1_CODE_HW = 0, + /* 4-bit ECC calculation by GPMC, Error detection by Software */ + OMAP_ECC_BCH4_CODE_HW_DETECTION_SW, + /* 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, + /* 8-bit ECC calculation by GPMC, Error detection by ELM */ + OMAP_ECC_BCH8_CODE_HW, }; struct gpmc_nand_regs { @@ -59,5 +66,6 @@ struct omap_nand_platform_data { /* for passing the partitions */ struct device_node *of_node; + struct device_node *elm_of_node; }; #endif