From patchwork Mon Nov 23 13:09:39 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ludovic Desroches X-Patchwork-Id: 7681231 Return-Path: X-Original-To: patchwork-dmaengine@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 063B0BF90C for ; Mon, 23 Nov 2015 13:11:24 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3370520704 for ; Mon, 23 Nov 2015 13:11:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4B4E7205DC for ; Mon, 23 Nov 2015 13:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752998AbbKWNKE (ORCPT ); Mon, 23 Nov 2015 08:10:04 -0500 Received: from eusmtp01.atmel.com ([212.144.249.243]:56624 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753983AbbKWNJz (ORCPT ); Mon, 23 Nov 2015 08:09:55 -0500 Received: from ibiza.corp.atmel.com (10.161.101.13) by eusmtp01.atmel.com (10.161.101.31) with Microsoft SMTP Server id 14.3.235.1; Mon, 23 Nov 2015 14:09:51 +0100 From: Ludovic Desroches To: CC: , , , , Ludovic Desroches Subject: [PATCH 2/2] dmaengine: at_xdmac: fix spurious flag status for mem2mem transfers Date: Mon, 23 Nov 2015 14:09:39 +0100 Message-ID: <1448284184-15171-2-git-send-email-ludovic.desroches@atmel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1448284184-15171-1-git-send-email-ludovic.desroches@atmel.com> References: <1448284184-15171-1-git-send-email-ludovic.desroches@atmel.com> MIME-Version: 1.0 Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, 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 When setting the channel configuration register, the perid field is not set to 0 since it is useless for mem2mem transfers. Unfortunately, a device has 0 as perid. It could cause spurious flags status because the controller could mix some events from the two channels. For that reason, use the highest perid value for mem2mem transfers since it doesn't match the perid of other devices. Signed-off-by: Ludovic Desroches Acked-by: Nicolas Ferre --- drivers/dma/at_xdmac.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index d09277f..b90e62f 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -863,8 +863,12 @@ at_xdmac_interleaved_queue_desc(struct dma_chan *chan, * access. Hopefully we can access DDR through both ports (at least on * SAMA5D4x), so we can use the same interface for source and dest, * that solves the fact we don't know the direction. + * ERRATA: Even if useless for memory transfers, the PERID has to not + * match the one of another channel. If not, it could lead to spurious + * flag status. */ - u32 chan_cc = AT_XDMAC_CC_DIF(0) + u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) + | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) | AT_XDMAC_CC_MBSIZE_SIXTEEN | AT_XDMAC_CC_TYPE_MEM_TRAN; @@ -1039,8 +1043,12 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, * access DDR through both ports (at least on SAMA5D4x), so we can use * the same interface for source and dest, that solves the fact we * don't know the direction. + * ERRATA: Even if useless for memory transfers, the PERID has to not + * match the one of another channel. If not, it could lead to spurious + * flag status. */ - u32 chan_cc = AT_XDMAC_CC_DAM_INCREMENTED_AM + u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) + | AT_XDMAC_CC_DAM_INCREMENTED_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) @@ -1140,8 +1148,12 @@ static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan, * access. Hopefully we can access DDR through both ports (at least on * SAMA5D4x), so we can use the same interface for source and dest, * that solves the fact we don't know the direction. + * ERRATA: Even if useless for memory transfers, the PERID has to not + * match the one of another channel. If not, it could lead to spurious + * flag status. */ - u32 chan_cc = AT_XDMAC_CC_DAM_UBS_AM + u32 chan_cc = AT_XDMAC_CC_PERID(0x3f) + | AT_XDMAC_CC_DAM_UBS_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0)