From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 13A8FEE0213 for ; Thu, 14 Sep 2023 03:00:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7u0TkBethkUQV3TILbvooSU6DdDMG5M9sjNVRbrEd2Q=; b=EPZZaWcTdn/BGf CqHio6BGF3nRAZOMfnOCuoTiNGYgCe+neSiL4qc8rlxo6+n4o+2LngOwRHHHMOBUbYP2RVz5+8tkT BHFjgsLR1Q2348zyLaOoItoGNQxIpRq85Q8JK8c4NYiVwfwxpVDIc2E5MBskdYFfRcHxQVjnmWDMA sQiT+ta3VbGVkWHr08OjyyGu+yS8TE067nGqUHOu6Y+oIRnS7WtmwgB743VylzryYCWTwLVrJKfwj I+nFdeyJROzqra9YtCYWsyaWeFF5RCIAzaTv39MyfkFebzK3IgEUJ7z6DEFweR0NgeCk5HE6DbuHl gXKt2TxKGI4cR6mSj2JA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qgcb6-007CvO-2D; Thu, 14 Sep 2023 03:00:52 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qgba2-0072iV-1i for linux-arm-kernel@lists.infradead.org; Thu, 14 Sep 2023 01:55:48 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6336661BE2; Thu, 14 Sep 2023 01:55:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6A5DC433C8; Thu, 14 Sep 2023 01:55:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694656541; bh=gXVhJOHHu42wAbkHvrobBuAxMZhcTwxM0j4OPJEY6D0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qG71OHQbCaL+Ti3zHuIzIPYGVRd66+PjwUbFGa3ApuSX6nVQebACo4fUqJs0KEp4Z k+SkH3r8R4IK5c+6DmKI0Oy8BkmjmALWRqYHgJIctNuxwnDCCkY9PBfvpq/gxwUuYG AiAw1Ko4OfmWKqTy7Z3xvcpEuKiS/wLUa9yQR6HE7Wk9CMcvNbgwDBfi17MVEnnBLd vRjI+C2IFMh27iM4FQCDBZCP9krp8XsWFrYpnjIED2Tmbrqpzm+uGHZ44fBRWf+qVc 6FJJDqOs2x5c1GyaaXM2wNhB9WGfmmP5wVdf7QbqdpHzrYPfaWx0aTMQ6f0uqGSxEF B4vsSPIPxQSLA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Tobias Schramm , Mark Brown , Sasha Levin , wens@csie.org, jernej.skrabec@gmail.com, samuel@sholland.org, linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev Subject: [PATCH AUTOSEL 5.15 2/3] spi: sun6i: reduce DMA RX transfer width to single byte Date: Wed, 13 Sep 2023 21:55:35 -0400 Message-Id: <20230914015536.51984-2-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230914015536.51984-1-sashal@kernel.org> References: <20230914015536.51984-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.131 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230913_185542_644380_417E501C X-CRM114-Status: GOOD ( 13.71 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Tobias Schramm [ Upstream commit 171f8a49f212e87a8b04087568e1b3d132e36a18 ] Through empirical testing it has been determined that sometimes RX SPI transfers with DMA enabled return corrupted data. This is down to single or even multiple bytes lost during DMA transfer from SPI peripheral to memory. It seems the RX FIFO within the SPI peripheral can become confused when performing bus read accesses wider than a single byte to it during an active SPI transfer. This patch reduces the width of individual DMA read accesses to the RX FIFO to a single byte to mitigate that issue. Signed-off-by: Tobias Schramm Link: https://lore.kernel.org/r/20230827152558.5368-2-t.schramm@manjaro.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-sun6i.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c index 23ad052528dbe..2bfe87873edb3 100644 --- a/drivers/spi/spi-sun6i.c +++ b/drivers/spi/spi-sun6i.c @@ -200,7 +200,7 @@ static int sun6i_spi_prepare_dma(struct sun6i_spi *sspi, struct dma_slave_config rxconf = { .direction = DMA_DEV_TO_MEM, .src_addr = sspi->dma_addr_rx, - .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, + .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, .src_maxburst = 8, }; -- 2.40.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel