From patchwork Mon Oct 19 08:57:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dylan Hung X-Patchwork-Id: 288353 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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 83EE4C43457 for ; Mon, 19 Oct 2020 08:57:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4410922200 for ; Mon, 19 Oct 2020 08:57:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729966AbgJSI5z (ORCPT ); Mon, 19 Oct 2020 04:57:55 -0400 Received: from twspam01.aspeedtech.com ([211.20.114.71]:65354 "EHLO twspam01.aspeedtech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729927AbgJSI5x (ORCPT ); Mon, 19 Oct 2020 04:57:53 -0400 Received: from mail.aspeedtech.com ([192.168.0.24]) by twspam01.aspeedtech.com with ESMTP id 09J8spsl046773; Mon, 19 Oct 2020 16:54:51 +0800 (GMT-8) (envelope-from dylan_hung@aspeedtech.com) Received: from localhost.localdomain (192.168.10.9) by TWMBX02.aspeed.com (192.168.0.24) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 19 Oct 2020 16:57:27 +0800 From: Dylan Hung To: , , , , , , CC: , Joel Stanley Subject: [PATCH 2/4] ftgmac100: Fix missing-poll issue Date: Mon, 19 Oct 2020 16:57:15 +0800 Message-ID: <20201019085717.32413-3-dylan_hung@aspeedtech.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201019085717.32413-1-dylan_hung@aspeedtech.com> References: <20201019085717.32413-1-dylan_hung@aspeedtech.com> MIME-Version: 1.0 X-Originating-IP: [192.168.10.9] X-ClientProxiedBy: TWMBX02.aspeed.com (192.168.0.24) To TWMBX02.aspeed.com (192.168.0.24) X-DNSRBL: X-MAIL: twspam01.aspeedtech.com 09J8spsl046773 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org the tx-poll command may advance the tx descriptor due the HW design. By adding a pseudo read and proper memory barrier, we can ensure all the data are ready before TX poll command. Fixes: 52c0cae87465 ("ftgmac100: Remove tx descriptor accessors") Signed-off-by: Dylan Hung Signed-off-by: Joel Stanley --- drivers/net/ethernet/faraday/ftgmac100.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index 7cacbe4aecb7..810bda80f138 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -814,8 +814,8 @@ static netdev_tx_t ftgmac100_hard_start_xmit(struct sk_buff *skb, * before setting the OWN bit on the first descriptor. */ dma_wmb(); - first->txdes0 = cpu_to_le32(f_ctl_stat); - + WRITE_ONCE(first->txdes0, cpu_to_le32(f_ctl_stat)); + READ_ONCE(first->txdes0); /* Update next TX pointer */ priv->tx_pointer = pointer;