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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 840B6C43219 for ; Tue, 30 Apr 2019 07:18:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 535412075E for ; Tue, 30 Apr 2019 07:18:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b="jUramFxI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726761AbfD3HS5 (ORCPT ); Tue, 30 Apr 2019 03:18:57 -0400 Received: from first.geanix.com ([116.203.34.67]:43798 "EHLO first.geanix.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726706AbfD3HSu (ORCPT ); Tue, 30 Apr 2019 03:18:50 -0400 Received: from localhost (unknown [193.163.1.7]) by first.geanix.com (Postfix) with ESMTPSA id F240B308EA3; Tue, 30 Apr 2019 07:18:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=geanix.com; s=first; t=1556608723; bh=d5jSy2G73aQlTbm0gKX8UO9SuypNh5XD4AWqgpyyw8o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jUramFxIeEYeFnLsreuoaW7Gk7DBAG10Otw/uPkYe2YOyWmGnXUvm+pDNooCBJg2U Hnf0GjP7UzeLsPaHFwg/93ZvrpzQdb82Bqh9ExCwpX71jP5vOqIgjlKC8WSWLHT0zr FKDIoeozLbhsrKW59/JPE/XcsfwQE89XX1IJbtEeuby/IQ6Kfc3k18lzUSXhQgYkgn zHi1oXQVFX/3LWkVcCToCDRbhi3CthF3zt4WamYw/QRNbuBAHFftmrrU5zqB0oR7eN tWBPzb2W3LYMqJVvbgbsm0C5whRJV2kS1kAS9LIf/J4JqyHh8wjNDp0LQf0Rjb5rFU Ml+pkAwmH9BOQ== From: Esben Haabendal To: netdev@vger.kernel.org Cc: "David S. Miller" , Michal Simek , Luis Chamberlain , YueHaibing , Yang Wei , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 12/12] net: ll_temac: Enable DMA when ready, not before Date: Tue, 30 Apr 2019 09:17:59 +0200 Message-Id: <20190430071759.2481-13-esben@geanix.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190430071759.2481-1-esben@geanix.com> References: <20190429083422.4356-1-esben@geanix.com> <20190430071759.2481-1-esben@geanix.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As soon as TAILDESCR_PTR is written, DMA transfers might start. Let's ensure we are ready to receive DMA IRQ's before doing that. Signed-off-by: Esben Haabendal --- drivers/net/ethernet/xilinx/ll_temac_main.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c index bccef30..1003ee1 100644 --- a/drivers/net/ethernet/xilinx/ll_temac_main.c +++ b/drivers/net/ethernet/xilinx/ll_temac_main.c @@ -314,17 +314,21 @@ static int temac_dma_bd_init(struct net_device *ndev) CHNL_CTRL_IRQ_EN | CHNL_CTRL_IRQ_ERR_EN | CHNL_CTRL_IRQ_DLY_EN | CHNL_CTRL_IRQ_COAL_EN); - lp->dma_out(lp, RX_CURDESC_PTR, lp->rx_bd_p); - lp->dma_out(lp, RX_TAILDESC_PTR, - lp->rx_bd_p + (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1))); - lp->dma_out(lp, TX_CURDESC_PTR, lp->tx_bd_p); - /* Init descriptor indexes */ lp->tx_bd_ci = 0; lp->tx_bd_next = 0; lp->tx_bd_tail = 0; lp->rx_bd_ci = 0; + /* Enable RX DMA transfers */ + wmb(); + lp->dma_out(lp, RX_CURDESC_PTR, lp->rx_bd_p); + lp->dma_out(lp, RX_TAILDESC_PTR, + lp->rx_bd_p + (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1))); + + /* Prepare for TX DMA transfer */ + lp->dma_out(lp, TX_CURDESC_PTR, lp->tx_bd_p); + return 0; out: @@ -789,6 +793,7 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev) skb_tx_timestamp(skb); /* Kick off the transfer */ + wmb(); lp->dma_out(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */ return NETDEV_TX_OK; -- 2.4.11