From patchwork Thu Aug 2 08:56:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Petazzoni X-Patchwork-Id: 952650 X-Patchwork-Delegate: miquel.raynal@bootlin.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="QNRLvYOa"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41h3vx4QK0z9s3x for ; Thu, 2 Aug 2018 18:57:16 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=74AtF2HqwGpmJ/X4aLD39CHG2K8TInKDWQfs6WiMQ0I=; b=QNR LvYOa6dKXshndgDveNWVKOEvu8hf3kInz3dIhdRRsHnLH6KTL/m5UwtqWWfCyzfV2LP2rdDCinUvc QnpUTGPsYcVT8FEos3DxAsq1okzn+yTzcbn+OhRWZevmn2k0pfzradWL2hSlFKsygkxXxHrO+YsHV uxpK74W/MC240rundSq3H9aZP8iKVjgHV3Kz4fd+7jGAEezqrgL6/S6lOf9s7QOSDAxXMED6ArTdn 6rTD1eg1bx7BTpeJ6mARyyebSa9/SD/mAGZTQ8X/8+T23/Vpbxcb8RK3aUFo8eTUqrgv6Kcy4aTi5 zipOFDAS0ttg53/bqafNSSD1G2WPeNQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fl9Pv-0007o1-6U; Thu, 02 Aug 2018 08:57:07 +0000 Received: from mail.bootlin.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fl9Pr-0007lk-JK for linux-mtd@lists.infradead.org; Thu, 02 Aug 2018 08:57:05 +0000 Received: by mail.bootlin.com (Postfix, from userid 110) id 8F1D0206F6; Thu, 2 Aug 2018 10:56:49 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on mail.bootlin.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.4.0 Received: from localhost (AAubervilliers-681-1-89-120.w90-88.abo.wanadoo.fr [90.88.30.120]) by mail.bootlin.com (Postfix) with ESMTPSA id 611742069C; Thu, 2 Aug 2018 10:56:39 +0200 (CEST) From: Thomas Petazzoni To: Miquel Raynal , Boris Brezillon , Richard Weinberger , linux-mtd@lists.infradead.org, Marek Vasut , David Woodhouse , Brian Norris Subject: [PATCH v2] mtd: nand: use regmap_update_bits() in marvell_nand for syscon access Date: Thu, 2 Aug 2018 10:56:25 +0200 Message-Id: <20180802085625.29635-1-thomas.petazzoni@bootlin.com> X-Mailer: git-send-email 2.14.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180802_015703_773112_75654BD7 X-CRM114-Status: GOOD ( 12.86 ) X-Spam-Score: -0.0 (/) X-Spam-Report: SpamAssassin version 3.4.1 on bombadil.infradead.org summary: Content analysis details: (-0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [62.4.15.54 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ofer Heifetz , Thomas Petazzoni MIME-Version: 1.0 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org The marvell_nfc_init() function fiddles with some bits of a system controller on Armada 7K/8K. However, it does a read/modify/write sequence on GENCONF_CLK_GATING_CTRL and GENCONF_ND_CLK_CTRL, which isn't safe from a concurrency point of view, as the regmap lock isn't taken accross the read/modify/write sequence. To solve this issue, use regmap_update_bits(). While at it, since the "reg" variable is no longer needed for the read/modify/write sequences, get rid of it for the regmap_write() to GENCONF_SOC_DEVICE_MUX, and directly pass the value to be written as argument. Fixes: 02f26ecf8c772 ("mtd: nand: add reworked Marvell NAND controller driver") Signed-off-by: Thomas Petazzoni --- Changes since v1: - Add Fixes: tag - Drop the regmap_update_bits() for GENCONF_SOC_DEVICE_MUX, and keep regmap_write(). This patch is not Cc'ed to stable, because it doesn't qualify according to the rule "It must fix a real bug that bothers people (not a, "This could be a problem..." type thing)" mentioned in Documentation/process/stable-kernel-rules.rst. --- drivers/mtd/nand/raw/marvell_nand.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/drivers/mtd/nand/raw/marvell_nand.c b/drivers/mtd/nand/raw/marvell_nand.c index ebb1d141b900..65aadbfa1fe8 100644 --- a/drivers/mtd/nand/raw/marvell_nand.c +++ b/drivers/mtd/nand/raw/marvell_nand.c @@ -2691,24 +2691,23 @@ static int marvell_nfc_init(struct marvell_nfc *nfc) struct regmap *sysctrl_base = syscon_regmap_lookup_by_phandle(np, "marvell,system-controller"); - u32 reg; if (IS_ERR(sysctrl_base)) return PTR_ERR(sysctrl_base); - reg = GENCONF_SOC_DEVICE_MUX_NFC_EN | - GENCONF_SOC_DEVICE_MUX_ECC_CLK_RST | - GENCONF_SOC_DEVICE_MUX_ECC_CORE_RST | - GENCONF_SOC_DEVICE_MUX_NFC_INT_EN; - regmap_write(sysctrl_base, GENCONF_SOC_DEVICE_MUX, reg); + regmap_write(sysctrl_base, GENCONF_SOC_DEVICE_MUX, + GENCONF_SOC_DEVICE_MUX_NFC_EN | + GENCONF_SOC_DEVICE_MUX_ECC_CLK_RST | + GENCONF_SOC_DEVICE_MUX_ECC_CORE_RST | + GENCONF_SOC_DEVICE_MUX_NFC_INT_EN); - regmap_read(sysctrl_base, GENCONF_CLK_GATING_CTRL, ®); - reg |= GENCONF_CLK_GATING_CTRL_ND_GATE; - regmap_write(sysctrl_base, GENCONF_CLK_GATING_CTRL, reg); + regmap_update_bits(sysctrl_base, GENCONF_CLK_GATING_CTRL, + GENCONF_CLK_GATING_CTRL_ND_GATE, + GENCONF_CLK_GATING_CTRL_ND_GATE); - regmap_read(sysctrl_base, GENCONF_ND_CLK_CTRL, ®); - reg |= GENCONF_ND_CLK_CTRL_EN; - regmap_write(sysctrl_base, GENCONF_ND_CLK_CTRL, reg); + regmap_update_bits(sysctrl_base, GENCONF_ND_CLK_CTRL, + GENCONF_ND_CLK_CTRL_EN, + GENCONF_ND_CLK_CTRL_EN); } /* Configure the DMA if appropriate */