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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCE09C433EF for ; Tue, 5 Jul 2022 12:13:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235433AbiGEMNo (ORCPT ); Tue, 5 Jul 2022 08:13:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234675AbiGEMHv (ORCPT ); Tue, 5 Jul 2022 08:07:51 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41441192BB; Tue, 5 Jul 2022 05:06:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BCA5E617B1; Tue, 5 Jul 2022 12:06:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C566DC341CB; Tue, 5 Jul 2022 12:06:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657022811; bh=P9EBvSno1J4Q6TM91bka1vnIcxP0MV0I7TioYm05TN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lyBK+olUu+E+EnwKz/sO4Dx3J4vCzip2cC1pGbuq/WP2cKsnZM3g1xjREv+uqnZgf 8pbOKXcdAzrw7k/7kElNaI4CmoDErCLFIt6YpTFVCGbZRPc3Z8XdHIsx/tZqMYS7o3 7fxyY4W5Dn8FxPIR+cpnbUPOy0KBHRujfaGKC7N4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Enguerrand de Ribaucourt , Andrew Lunn , Jakub Kicinski Subject: [PATCH 5.10 19/84] net: dp83822: disable false carrier interrupt Date: Tue, 5 Jul 2022 13:57:42 +0200 Message-Id: <20220705115615.886314240@linuxfoundation.org> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220705115615.323395630@linuxfoundation.org> References: <20220705115615.323395630@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Enguerrand de Ribaucourt commit c96614eeab663646f57f67aa591e015abd8bd0ba upstream. When unplugging an Ethernet cable, false carrier events were produced by the PHY at a very high rate. Once the false carrier counter full, an interrupt was triggered every few clock cycles until the cable was replugged. This resulted in approximately 10k/s interrupts. Since the false carrier counter (FCSCR) is never used, we can safely disable this interrupt. In addition to improving performance, this also solved MDIO read timeouts I was randomly encountering with an i.MX8 fec MAC because of the interrupt flood. The interrupt count and MDIO timeout fix were tested on a v5.4.110 kernel. Fixes: 87461f7a58ab ("net: phy: DP83822 initial driver submission") Signed-off-by: Enguerrand de Ribaucourt Reviewed-by: Andrew Lunn Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/dp83822.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/net/phy/dp83822.c +++ b/drivers/net/phy/dp83822.c @@ -244,7 +244,6 @@ static int dp83822_config_intr(struct ph return misr_status; misr_status |= (DP83822_RX_ERR_HF_INT_EN | - DP83822_FALSE_CARRIER_HF_INT_EN | DP83822_LINK_STAT_INT_EN | DP83822_ENERGY_DET_INT_EN | DP83822_LINK_QUAL_INT_EN);