From patchwork Wed Mar 13 19:55:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bryan Whitehead X-Patchwork-Id: 1056201 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=none (p=none dis=none) header.from=microchip.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44KN1S3Hmgz9s3q for ; Thu, 14 Mar 2019 06:58:04 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727051AbfCMT6C (ORCPT ); Wed, 13 Mar 2019 15:58:02 -0400 Received: from esa6.microchip.iphmx.com ([216.71.154.253]:63259 "EHLO esa6.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726860AbfCMT6C (ORCPT ); Wed, 13 Mar 2019 15:58:02 -0400 X-IronPort-AV: E=Sophos;i="5.58,475,1544511600"; d="scan'208";a="25274370" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa6.microchip.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 13 Mar 2019 12:58:01 -0700 Received: from BW-Ubuntu-tester.mchp-main.com (10.10.76.4) by chn-sv-exch06.mchp-main.com (10.10.76.107) with Microsoft SMTP Server id 14.3.352.0; Wed, 13 Mar 2019 12:58:00 -0700 From: Bryan Whitehead To: CC: , Subject: [PATCH v1 net] lan743x: Fix TX Stall Issue Date: Wed, 13 Mar 2019 15:55:48 -0400 Message-ID: <1552506948-6863-1-git-send-email-Bryan.Whitehead@microchip.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org It has been observed that tx queue may stall while downloading from certain web sites (example www.speedtest.net) The cause has been tracked down to a corner case where the tx interrupt vector was disabled automatically, but was not re enabled later. The lan743x has two mechanisms to enable/disable individual interrupts. Interrupts can be enabled/disabled by individual source, and they can also be enabled/disabled by individual vector which has been mapped to the source. Both must be enabled for interrupts to work properly. The TX code path, primarily uses the interrupt enable/disable of the TX source bit, while leaving the vector enabled all the time. However, while investigating this issue it was noticed that the driver requested the use of the vector auto clear feature. The test above revealed a case where the vector enable was cleared unintentionally. This patch fixes the issue by deleting the lines that request the vector auto clear feature to be used. Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Bryan Whitehead --- drivers/net/ethernet/microchip/lan743x_main.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index 2876bab..13e6bf1 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -585,8 +585,7 @@ static int lan743x_intr_open(struct lan743x_adapter *adapter) if (adapter->csr.flags & LAN743X_CSR_FLAG_SUPPORTS_INTR_AUTO_SET_CLR) { - flags = LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_CLEAR | - LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET | + flags = LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_SET | LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_SET | LAN743X_VECTOR_FLAG_SOURCE_ENABLE_AUTO_CLEAR | LAN743X_VECTOR_FLAG_SOURCE_STATUS_AUTO_CLEAR; @@ -599,12 +598,6 @@ static int lan743x_intr_open(struct lan743x_adapter *adapter) /* map TX interrupt to vector */ int_vec_map1 |= INT_VEC_MAP1_TX_VEC_(index, vector); lan743x_csr_write(adapter, INT_VEC_MAP1, int_vec_map1); - if (flags & - LAN743X_VECTOR_FLAG_VECTOR_ENABLE_AUTO_CLEAR) { - int_vec_en_auto_clr |= INT_VEC_EN_(vector); - lan743x_csr_write(adapter, INT_VEC_EN_AUTO_CLR, - int_vec_en_auto_clr); - } /* Remove TX interrupt from shared mask */ intr->vector_list[0].int_mask &= ~int_bit;