From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout2.samsung.com ([203.254.224.25]) by bombadil.infradead.org with esmtp (Exim 4.72 #1 (Red Hat Linux)) id 1OqE5e-0006Eh-Dc for linux-mtd@lists.infradead.org; Mon, 30 Aug 2010 23:48:39 +0000 Received: from epmmp2 (mailout2.samsung.com [203.254.224.25]) by mailout2.samsung.com (Sun Java(tm) System Messaging Server 7u3-15.01 64bit (built Feb 12 2010)) with ESMTP id <0L7Z0071IOS4QO70@mailout2.samsung.com> for linux-mtd@lists.infradead.org; Tue, 31 Aug 2010 08:48:04 +0900 (KST) Received: from TNRNDGASPAPP1.tn.corp.samsungelectronics.net ([165.213.149.150]) by mmp2.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0L7Z00HELOS49M@mmp2.samsung.com> for linux-mtd@lists.infradead.org; Tue, 31 Aug 2010 08:48:04 +0900 (KST) Date: Tue, 31 Aug 2010 08:48:01 +0900 From: Kyungmin Park Subject: [PATCH v2] MTD: OneNAND: Fix loop hang when DMA error at Samsung SoCs To: linux-mtd@lists.infradead.org Message-id: <20100830234801.GA16862@july> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT Content-disposition: inline Cc: Artem.Bityutskiy@nokia.com, dwmw2@infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Kyungmin Park When DMA error occurs. it's loop hang since it can't exit the loop. and it's the right DMA handling code as Spec. Signed-off-by: Kyungmin Park --- Changelog v1 Add the timeout as Artem comment drivers/mtd/onenand/samsung.c | 17 ++++++++++------- 1 files changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/mtd/onenand/samsung.c b/drivers/mtd/onenand/samsung.c index d604629..bdaa228 100644 --- a/drivers/mtd/onenand/samsung.c +++ b/drivers/mtd/onenand/samsung.c @@ -535,6 +535,7 @@ static int s5pc110_dma_ops(void *dst, void *src, size_t count, int direction) { void __iomem *base = onenand->dma_addr; int status; + unsigned long timeout; writel(src, base + S5PC110_DMA_SRC_ADDR); writel(dst, base + S5PC110_DMA_DST_ADDR); @@ -552,15 +553,17 @@ static int s5pc110_dma_ops(void *dst, void *src, size_t count, int direction) writel(S5PC110_DMA_TRANS_CMD_TR, base + S5PC110_DMA_TRANS_CMD); + timeout = jiffies + msec_to_jiffies(20); + do { status = readl(base + S5PC110_DMA_TRANS_STATUS); - } while (!(status & S5PC110_DMA_TRANS_STATUS_TD)); - - if (status & S5PC110_DMA_TRANS_STATUS_TE) { - writel(S5PC110_DMA_TRANS_CMD_TEC, base + S5PC110_DMA_TRANS_CMD); - writel(S5PC110_DMA_TRANS_CMD_TDC, base + S5PC110_DMA_TRANS_CMD); - return -EIO; - } + if (status & S5PC110_DMA_TRANS_STATUS_TE) { + writel(S5PC110_DMA_TRANS_CMD_TEC, + base + S5PC110_DMA_TRANS_CMD); + return -EIO; + } + } while (!(status & S5PC110_DMA_TRANS_STATUS_TD) && + time_before(jiffies, timeout)); writel(S5PC110_DMA_TRANS_CMD_TDC, base + S5PC110_DMA_TRANS_CMD); -- 1.5.3.3