From patchwork Fri Jan 6 20:07:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Grygorii Strashko X-Patchwork-Id: 712138 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3twFwt433Gz9t1B for ; Sat, 7 Jan 2017 07:08:30 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161337AbdAFUIA (ORCPT ); Fri, 6 Jan 2017 15:08:00 -0500 Received: from lelnx193.ext.ti.com ([198.47.27.77]:11067 "EHLO lelnx193.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S937976AbdAFUHk (ORCPT ); Fri, 6 Jan 2017 15:07:40 -0500 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by lelnx193.ext.ti.com (8.15.1/8.15.1) with ESMTP id v06K7cir022634; Fri, 6 Jan 2017 14:07:38 -0600 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id v06K7cC8006695; Fri, 6 Jan 2017 14:07:38 -0600 Received: from dflp32.itg.ti.com (10.64.6.15) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.3.294.0; Fri, 6 Jan 2017 14:07:37 -0600 Received: from legion.dal.design.ti.com (legion.dal.design.ti.com [128.247.22.53]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id v06K7bVd007720; Fri, 6 Jan 2017 14:07:37 -0600 Received: from localhost (uda0226610.am.dhcp.ti.com [128.247.83.96]) by legion.dal.design.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id v06K7b311519; Fri, 6 Jan 2017 14:07:37 -0600 (CST) From: Grygorii Strashko To: "David S. Miller" , , Mugunthan V N , Ivan Khoronzhuk CC: Sekhar Nori , , , Grygorii Strashko Subject: [PATCH v2 2/7] net: ethernet: ti: cpdma: fix desc re-queuing Date: Fri, 6 Jan 2017 14:07:30 -0600 Message-ID: <20170106200735.4210-3-grygorii.strashko@ti.com> X-Mailer: git-send-email 2.10.1.dirty In-Reply-To: <20170106200735.4210-1-grygorii.strashko@ti.com> References: <20170106200735.4210-1-grygorii.strashko@ti.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The currently processing cpdma descriptor with EOQ flag set may contain two values in Next Descriptor Pointer field: - valid pointer: means CPDMA missed addition of new desc in queue; - null: no more descriptors in queue. In the later case, it's not required to write to HDP register, but now CPDMA does it. Hence, add additional check for Next Descriptor Pointer != null in cpdma_chan_process() function before writing in HDP register. Signed-off-by: Grygorii Strashko --- drivers/net/ethernet/ti/davinci_cpdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c index d6f0ded..a53b384 100644 --- a/drivers/net/ethernet/ti/davinci_cpdma.c +++ b/drivers/net/ethernet/ti/davinci_cpdma.c @@ -1159,7 +1159,7 @@ static int __cpdma_chan_process(struct cpdma_chan *chan) chan->count--; chan->stats.good_dequeue++; - if (status & CPDMA_DESC_EOQ) { + if ((status & CPDMA_DESC_EOQ) && chan->head) { chan->stats.requeue++; chan_write(chan, hdp, desc_phys(pool, chan->head)); }