From nobody Mon Sep 8 08:46:40 2025 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 38623C6FA86 for ; Tue, 13 Sep 2022 15:32:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233459AbiIMPcV (ORCPT ); Tue, 13 Sep 2022 11:32:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232242AbiIMPbu (ORCPT ); Tue, 13 Sep 2022 11:31:50 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 729AB7E80D; Tue, 13 Sep 2022 07:40:23 -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 ams.source.kernel.org (Postfix) with ESMTPS id 7310BB80F03; Tue, 13 Sep 2022 14:26:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC31CC433D6; Tue, 13 Sep 2022 14:26:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1663079164; bh=Ir6xP5RljXZWlqFSh5Ec+G4wO4Kw9CDLZq4owOGGAYg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gOBJPHXZjazCb+61w6cI/RgEy1wR1Mzasi4a8M7ayma8PiRN/5SrnBc1noCbkqDK7 w9Dhe3RKZ7BRp6Z/eZMdrwUcKXb989cgb35Czg5zcgzMegvAPii+ExIAfhAWNvDJzq wRNa+NwgiWJBW210RORiuNVkLKgc9mZQ8vTEOq0I= 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 5.4 006/108] net: dp83822: disable false carrier interrupt Date: Tue, 13 Sep 2022 16:05:37 +0200 Message-Id: <20220913140353.827815251@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220913140353.549108748@linuxfoundation.org> References: <20220913140353.549108748@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 @@ -198,7 +198,6 @@ static int dp83822_config_intr(struct ph return misr_status; =20 misr_status |=3D (DP83822_RX_ERR_HF_INT_EN | - DP83822_FALSE_CARRIER_HF_INT_EN | DP83822_ANEG_COMPLETE_INT_EN | DP83822_DUP_MODE_CHANGE_INT_EN | DP83822_SPEED_CHANGED_INT_EN |