From patchwork Wed Dec 19 11:03:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 154247 Delivered-To: patch@linaro.org Received: by 2002:a2e:299d:0:0:0:0:0 with SMTP id p29-v6csp4796901ljp; Wed, 19 Dec 2018 03:03:55 -0800 (PST) X-Google-Smtp-Source: AFSGD/Wzj9Vv/yTqhxe8voP6zFqEYsKlHRj32cREq55/XrjLIMhbeaYG7upgiRLfmrHlNnUNGhnw X-Received: by 2002:a50:94f4:: with SMTP id t49mr19907756eda.24.1545217434904; Wed, 19 Dec 2018 03:03:54 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1545217434; cv=none; d=google.com; s=arc-20160816; b=QqtO88YJnsG4cMTKFt82z/vaPzQw4uwr77Lk3bKNCkX1nSmpCS0+ycsvkczvLSz8/v KyZSEm7cKVHhdStiQxJBBYlLy47r6ldk4AAYk3lOr1O622Uq/yIfNxQzZpPqJSSmPcK4 G4UVaE+eKPZyHSF2hIrl/BPJYY6EtKOzJwrKVe61+voEZPg4p7FOqfI5dP1Tt0b0d3KL m2SSNddf8wdIzrEIL1Qga6b/huSKzwoU/BR7vl18COdVLbmGI4O0olkr0nOIbxFgkA3j gSgYB+PPU3l00UQpuMYNakBxvnIXsgk3vgTpVYvfkzjfpwlUeRN14sTZWyIGaqeqWe8o AtKg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:mime-version :list-subscribe:list-help:list-post:list-archive:list-unsubscribe :list-id:precedence:subject:references:in-reply-to:message-id:date :to:from:dkim-signature:dkim-filter; bh=eixbl+YheKw3JLl23RDPOhrABawJlREv1uoTXFPoWSc=; b=CV/4nuB8qviCvHrko/+Al8HnJdJXCAu54bNiEGWlgCUWjoRQ+615CL1Ve9VcQNZE1Z oFTDmWaofz1ZEF69W982/grcLooDAxp1TjlnCQlVIphRzQkhApSBLCDZ2pn7hT2YGeyh 5VIghX2QIM1jykYeM3wUT4lcHAtq8Y9qWnHzkVsUYsGXBi8f2wC5TvU/nn0SaHxCbiVX c2/JORUzawkx+apphkvOuh2QLgaRx3I0rNQ2fYxTpCgDcMC5w0usTsEDRoxngxN6vOH6 X/D7LBHHHt79S/Hupo8LaKrJHsvLsjSQrq0SPK38I1fTuX5dKn9tXyNHPgpeQ7rXFAHW reGA== ARC-Authentication-Results: i=1; mx.google.com; dkim=neutral (body hash did not verify) header.i=@nifty.com header.s=dec2015msa header.b=Eq+5iwel; spf=pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de Return-Path: Received: from lists.denx.de (dione.denx.de. [81.169.180.215]) by mx.google.com with ESMTP id u28si4195688edi.62.2018.12.19.03.03.54; Wed, 19 Dec 2018 03:03:54 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) client-ip=81.169.180.215; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@nifty.com header.s=dec2015msa header.b=Eq+5iwel; spf=pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by lists.denx.de (Postfix, from userid 105) id 083DAC22076; Wed, 19 Dec 2018 11:03:51 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lists.denx.de X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.0 Received: from lists.denx.de (localhost [IPv6:::1]) by lists.denx.de (Postfix) with ESMTP id 7BD2BC21EF2; Wed, 19 Dec 2018 11:03:48 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id 964ADC21F98; Wed, 19 Dec 2018 11:03:47 +0000 (UTC) Received: from conuserg-09.nifty.com (conuserg-09.nifty.com [210.131.2.76]) by lists.denx.de (Postfix) with ESMTPS id A14F1C21EF2 for ; Wed, 19 Dec 2018 11:03:46 +0000 (UTC) Received: from pug.e01.socionext.com (p14092-ipngnfx01kyoto.kyoto.ocn.ne.jp [153.142.97.92]) (authenticated) by conuserg-09.nifty.com with ESMTP id wBJB3SMQ001192; Wed, 19 Dec 2018 20:03:32 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-09.nifty.com wBJB3SMQ001192 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1545217412; bh=WGRl6r1m0R2t/3xEAjlOKP8P9bQAZMbu/0pdWlomXek=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Eq+5iwelcFOgbt5fL6ica82gxB/nphab4LICNYxr9AkXOuXjN4KuhiRPQkOJUuqGC wQsIY0BfbuRxk06vDV5voKxjhzq1sr97yu0dR+YqW6p7QmuO8eB0a4gOrlaVHSeDr/ XtUjFxltlSaimVS5CjuTatRn2pQJbxg0dbUCgdMsUHOUU3N3bqbX/CzM60RCJWg7vx up7p6OzutakxaxmnvA7MbY76uLmN2uTewYmENYtCAGzjMB2HrQ9EGq3k9r5lajA5xA 5gna1xS8fV2u2u1U4Bxx6J/h1/k1vfS4b56a3k/VCJ5BnJukLFcjuMtrqx9IyohqK3 fjtOE9DvX3KUQ== X-Nifty-SrcIP: [153.142.97.92] From: Masahiro Yamada To: u-boot@lists.denx.de Date: Wed, 19 Dec 2018 20:03:19 +0900 Message-Id: <1545217401-27018-8-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1545217401-27018-1-git-send-email-yamada.masahiro@socionext.com> References: <1545217401-27018-1-git-send-email-yamada.masahiro@socionext.com> Subject: [U-Boot] [PATCH 7/9] mtd: rawnand: denali: fix a race condition when DMA is kicked X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.18 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" Based on Linux commit cf51e4b9c34407bf0c3d9b582b7837e047e1df47 Add the register read-back, commenting why this is necessary. Signed-off-by: Masahiro Yamada --- drivers/mtd/nand/raw/denali.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c index bbfa3b6..e0eb133 100644 --- a/drivers/mtd/nand/raw/denali.c +++ b/drivers/mtd/nand/raw/denali.c @@ -587,6 +587,12 @@ static int denali_dma_xfer(struct denali_nand_info *denali, void *buf, } iowrite32(DMA_ENABLE__FLAG, denali->reg + DMA_ENABLE); + /* + * The ->setup_dma() hook kicks DMA by using the data/command + * interface, which belongs to a different AXI port from the + * register interface. Read back the register to avoid a race. + */ + ioread32(denali->reg + DMA_ENABLE); denali_reset_irq(denali); denali->setup_dma(denali, dma_addr, page, write);