From patchwork Mon Jul 29 13:29:53 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 2834982 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0DEBFC0319 for ; Mon, 29 Jul 2013 13:32:23 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DEF93201F5 for ; Mon, 29 Jul 2013 13:32:21 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8310020205 for ; Mon, 29 Jul 2013 13:32:20 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V3nY0-0005GW-GJ; Mon, 29 Jul 2013 13:31:37 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V3nXi-0001Oa-A0; Mon, 29 Jul 2013 13:31:18 +0000 Received: from bear.ext.ti.com ([192.94.94.41]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V3nXE-0001JC-5u for linux-arm-kernel@lists.infradead.org; Mon, 29 Jul 2013 13:30:53 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6TDUJvQ011171; Mon, 29 Jul 2013 08:30:19 -0500 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6TDUI96007996; Mon, 29 Jul 2013 08:30:18 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.2.342.3; Mon, 29 Jul 2013 08:30:18 -0500 Received: from joel-laptop.itg.ti.com (h0-79.vpn.ti.com [172.24.0.79]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6TDTuP5008221; Mon, 29 Jul 2013 08:30:17 -0500 From: Joel Fernandes To: Tony Lindgren , Sekhar Nori , Santosh Shilimkar , Sricharan R , Rajendra Nayak , Lokesh Vutla , Matt Porter , Grant Likely , Rob Herring , Vinod Koul , Dan Williams , Mark Brown , Benoit Cousson , Russell King , Arnd Bergmann , Olof Johansson , Balaji TK , Gururaja Hebbar , Chris Ball , Jason Kridner Subject: [PATCH 7/9] ARM: edma: Don't clear EMR of channel in edma_stop Date: Mon, 29 Jul 2013 08:29:53 -0500 Message-ID: <1375104595-16018-8-git-send-email-joelf@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1375104595-16018-1-git-send-email-joelf@ti.com> References: <1375104595-16018-1-git-send-email-joelf@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130729_093048_641399_270D2D73 X-CRM114-Status: GOOD ( 14.20 ) X-Spam-Score: -8.4 (--------) Cc: Linux DaVinci Kernel List , Joel Fernandes , Linux MMC List , Linux Kernel Mailing List , Linux OMAP List , Linux ARM Kernel List X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 We certainly don't want error conditions to be cleared anywhere as this will make us 'forget' about missed events. We depend on knowing which events were missed in order to be able to reissue them. This fixes a race condition where the EMR was being cleared by the transfer completion interrupt handler. Basically, what was happening was: Missed event | | V SG1-SG2-SG3-Null \ \__TC Interrupt (Almost same time as ARM is executing TC interrupt handler, an event got missed and also forgotten by clearing the EMR). The EMR is ultimately being cleared by the Error interrupt handler once it is handled so we don't have to do it in edma_stop. Signed-off-by: Joel Fernandes --- arch/arm/common/edma.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c index 10995b2..dec772e 100644 --- a/arch/arm/common/edma.c +++ b/arch/arm/common/edma.c @@ -1328,7 +1328,6 @@ void edma_stop(unsigned channel) edma_shadow0_write_array(ctlr, SH_EECR, j, mask); edma_shadow0_write_array(ctlr, SH_ECR, j, mask); edma_shadow0_write_array(ctlr, SH_SECR, j, mask); - edma_write_array(ctlr, EDMA_EMCR, j, mask); pr_debug("EDMA: EER%d %08x\n", j, edma_shadow0_read_array(ctlr, SH_EER, j));