From patchwork Tue Apr 30 07:17:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Esben Haabendal X-Patchwork-Id: 1093045 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=geanix.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=geanix.com header.i=@geanix.com header.b="jUramFxI"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44tXvT6z2Dz9s9T for ; Tue, 30 Apr 2019 17:19:01 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726744AbfD3HS4 (ORCPT ); Tue, 30 Apr 2019 03:18:56 -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 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, UNPARSEABLE_RELAY, URIBL_BLOCKED autolearn=disabled version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on b7bf6291adac Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@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;