From patchwork Tue Mar 14 00:41:37 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Berger X-Patchwork-Id: 738503 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 3vhwvs49jtz9s75 for ; Tue, 14 Mar 2017 11:43:37 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="YRZj1rhQ"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754181AbdCNAmd (ORCPT ); Mon, 13 Mar 2017 20:42:33 -0400 Received: from mail-qt0-f196.google.com ([209.85.216.196]:33106 "EHLO mail-qt0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754118AbdCNAm3 (ORCPT ); Mon, 13 Mar 2017 20:42:29 -0400 Received: by mail-qt0-f196.google.com with SMTP id r45so8350377qte.0; Mon, 13 Mar 2017 17:42:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=fJmjEAQxIZx0ic/Ptm2wxDt5uUiVYp6mQYhcZnx6tis=; b=YRZj1rhQs8Qlow6Pw+tYkMWb6vN1/ctdPPGQ2VhZt52TkWci3s1dxqTCbWGsy8mkp5 UpBZoB/oMZt2GG7hfJUSvaPM34ClEhLTwhqpupJl8KCgwqK/1aZpSVjIxVMFOHQY1eCb ehy94RfKoSLNuz5k7k3S3wKisTyl3qqkVNXgvAjDRSlV02npl5tqwDfZmdul33ZIaCVV VhsG/GJ4PSpwN14T8N2G8fhJtbdulIGzIcF9Ufbj+k5Sq3WD0GZqb+TCSXb02FoVAJS8 J7iM7UKNYPkADbskHHDUEpw4eQW+p/xEt5GkWaWDjDbYv8XlFIw9YqzO7DBw/5byZ3Tv t2YA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=fJmjEAQxIZx0ic/Ptm2wxDt5uUiVYp6mQYhcZnx6tis=; b=XsNOxcyZw2IQxeKaE20JEo8gumMz3bllb5Oc1w4wERfU76ePcpck4gHddZRGhmVKSH lFgk7Tt4Czcurpw/wla+7aGUO8r+r4pfhH37ZjETiTStE1Eh/AhHoSlLzVRSBISY7RF7 tZ6Aof463AK9PLkfE9eA1tHwyvPJYhxZPCcaBpldry4EhYLBU8sc9tFJWT6ZhvZY3YA0 pUI+kuAUMflI0ts8m1VTx0n3rP2HQlo7nUrbtP4AQIjgiWW7Dd/21NuORgGRXo9Le4s5 gk/R6fthpwYEb4jd8OOthbRBZ85t3o3zWWFTEyR61kG5fOywhjrGiuWkdeFQzYMaeA1/ t+hg== X-Gm-Message-State: AMke39mqlV/tuzC2ikjJWfZ64AYPs17PPrS4Lnaw9GTArQTac/H9YVzYI5ffMjnr4/KIUQ== X-Received: by 10.200.51.152 with SMTP id c24mr38070101qtb.31.1489452138176; Mon, 13 Mar 2017 17:42:18 -0700 (PDT) Received: from stb-bld-02.irv.broadcom.com ([192.19.255.250]) by smtp.gmail.com with ESMTPSA id y52sm13353343qty.60.2017.03.13.17.42.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 13 Mar 2017 17:42:17 -0700 (PDT) From: Doug Berger To: f.fainelli@gmail.com Cc: robh+dt@kernel.org, mark.rutland@arm.com, davem@davemloft.net, rafal@milecki.pl, xow@google.com, joel@jms.id.au, jon.mason@broadcom.com, netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, pgynther@google.com, jaedon.shin@gmail.com, Doug Berger Subject: [PATCH net-next 07/12] net: bcmgenet: clear status to reduce spurious interrupts Date: Mon, 13 Mar 2017 17:41:37 -0700 Message-Id: <20170314004142.4746-8-opendmb@gmail.com> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20170314004142.4746-1-opendmb@gmail.com> References: <20170314004142.4746-1-opendmb@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Since the DMA interrupt status is latched and the DMA servicing can be polled, it is a good idea to clear the latched status of a DMA interrupt before performing the service that would be invoked by the interrupt. This prevents old status from causing spurious interrupts when the interrupt is unmasked at a later time. Signed-off-by: Doug Berger Reviewed-by: Florian Fainelli --- drivers/net/ethernet/broadcom/genet/bcmgenet.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c index 661ca1b39c89..1f94ba1773dd 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c @@ -1174,6 +1174,14 @@ static unsigned int __bcmgenet_tx_reclaim(struct net_device *dev, unsigned int txbds_ready; unsigned int txbds_processed = 0; + /* Clear status before servicing to reduce spurious interrupts */ + if (ring->index == DESC_INDEX) + bcmgenet_intrl2_0_writel(priv, UMAC_IRQ_TXDMA_DONE, + INTRL2_CPU_CLEAR); + else + bcmgenet_intrl2_1_writel(priv, (1 << ring->index), + INTRL2_CPU_CLEAR); + /* Compute how many buffers are transmitted since last xmit call */ c_index = bcmgenet_tdma_ring_readl(priv, ring->index, TDMA_CONS_INDEX) & DMA_C_INDEX_MASK; @@ -1584,10 +1592,21 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_rx_ring *ring, unsigned long dma_flag; int len; unsigned int rxpktprocessed = 0, rxpkttoprocess; - unsigned int p_index; + unsigned int p_index, mask; unsigned int discards; unsigned int chksum_ok = 0; + /* Clear status before servicing to reduce spurious interrupts */ + if (ring->index == DESC_INDEX) { + bcmgenet_intrl2_0_writel(priv, UMAC_IRQ_RXDMA_DONE, + INTRL2_CPU_CLEAR); + } else { + mask = 1 << (UMAC_IRQ1_RX_INTR_SHIFT + ring->index); + bcmgenet_intrl2_1_writel(priv, + mask, + INTRL2_CPU_CLEAR); + } + p_index = bcmgenet_rdma_ring_readl(priv, ring->index, RDMA_PROD_INDEX); discards = (p_index >> DMA_P_INDEX_DISCARD_CNT_SHIFT) &