From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=192.19.144.205 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792609852; b=Pre8ckhVT7y2a2mG3PNapO30aSDXep4jB/bYt7jp0U5En2MOGlNNRF+Zerzi2mp5CJhE oGxyGT+yMewvjRexn9GJH8ZD+1NnKj07CFlgjLDYh877Yh1qpsong1CUklh0bkjxIi5S+ Ltof1Z5CRe2Cn/1vEfQE1hUN5mTPVFKaBMO7mj1/xszK/Et4DdyPXycYshWc0yVdPbWSJ wlJPV15zfYoA1RtG0Hb9A9rS1tm39uqWK+dFqQdXsxAw3nVBeoWz9KFisIGxI1VAoZy2h lwvWRZ4aVJQfujdKcVT+9brjGzNEOpWJ7ULUX1QpKt/v3QyAjBRI/XKB3B8mVtvEz/Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792609852; h=DMARC-Filter:Received:DKIM-Filter:DKIM-Signature:Received:From:To:Cc: Subject:Date:Message-ID:X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=mZnLYWYthQyH/1Q08I94hYQu+8M2DcuSm/l3CvY+1vI=; b=BmlZrlk+CSwt2f87KkyAxcqxmA6CUVmzrs6vz0aSfXpnpta0jt5fvOTPN8T0esCMU1/R XsZe3A9TBuDUiMu9ETIJakAtvRpIzHRkDFZKBEt1MHKuyWgryq7IeT+dWADSLJRYCa4Su mSUFzvmmRMdXR9g3wuWqgDOtMTdi78rmuL9Uz/c0QgdBSxEBRzpzfP+VjCN9u7/g3RWl/ NaDbolzdRh+3m+5NTawa65tq3gbK7RLtyypIbwnkOuK2jsJh8NKBwEzko9b5GeOTBWPNj +rgkAu+ZBw4x2qnaBDck5GFrfuOox0d55LCR+pVj6GoGZVHDJBNTvEgzF9Whc/tQBPA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=broadcom.com; spf=fail smtp.mailfrom=broadcom.com; dkim=pass header.d=broadcom.com header.i=@broadcom.com header.a=rsa-sha256 header.s=dkimrelay header.b=FPEFi5sf; arc=none smtp.remote-ip=192.19.144.205 Received: from relay.smtp-ext.broadcom.com (lpdvsmtp10.broadcom.com [192.19.144.205]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 73796606A31A; Wed, 21 Oct 2026 19:10:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 73796606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=broadcom.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=broadcom.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=broadcom.com header.i=@broadcom.com header.a=rsa-sha256 header.s=dkimrelay header.b=FPEFi5sf Received: from mail-lvn-it-01.broadcom.com (mail-lvn-it-01.lvn.broadcom.net [10.36.132.253]) by relay.smtp-ext.broadcom.com (Postfix) with ESMTP id 3089DC0003E6; Wed, 21 Oct 2026 12:10:50 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 relay.smtp-ext.broadcom.com 3089DC0003E6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=broadcom.com; s=dkimrelay; t=1792609850; bh=/A5oZYXNQMjUMploRdqR03mvQq8qWvVx5LgB4bTZe0A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FPEFi5sf/RkgD70EOa8WjoESgD0XOeNY19+1DZFYld6W6j4wvXWzpjz5Du+G7LLz/ 5jzaT7JiYcHY0qjfEEmb6mtf8FYFQCKzNktKeMQCJjTO4k/MDXHQf/qzbOjciJaYCR dlBwBzHtZBaj2kNZIHIEygsp8a9oUc9sPqwXgToY= Received: from fainelli-desktop.igp.broadcom.net (fainelli-desktop.dhcp.broadcom.net [10.67.48.245]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail-lvn-it-01.broadcom.com (Postfix) with ESMTPSA id BF9E0A88; Wed, 21 Oct 2026 12:10:49 -0700 (PDT) From: Florian Fainelli To: netdev@vger.kernel.org Cc: Florian Fainelli , Jonas Gorski , Andrew Lunn , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= , Broadcom internal kernel review list , Russell King , Jon Mason , Arnd Bergmann , linux-kernel@vger.kernel.org (open list) Subject: [PATCH net 1/2] net: ethernet: bgmac: preserve forced 2.5 Gbps link speed Date: Wed, 21 Oct 2026 12:10:34 -0700 Message-ID: <20261021191035.751684-2-florian.fainelli@broadcom.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261021191035.751684-1-florian.fainelli@broadcom.com> References: <20261021191035.751684-1-florian.fainelli@broadcom.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Northstar and Northstar Plus use a 2.5 Gbps internal link between the AMAC and the switch. BGMAC_FEAT_FORCE_SPEED_2500 makes bgmac_miiconfig() configure that speed, but bgmac_adjust_link() subsequently replaces it with the synthetic fixed PHY's 1 Gbps speed. Use the forced speed when processing link changes so the MAC remains at 2.5 Gbps. Together with configuring the switch IMP port for its 2 Gbps mode, this eliminates the output queue discards that caused approximately 1000 TCP retransmissions per second during an iperf3 transmit test. Fixes: f6a95a24957a ("net: ethernet: bgmac: Add platform device support") Signed-off-by: Florian Fainelli --- drivers/net/ethernet/broadcom/bgmac.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bgmac.c b/drivers/net/ethernet/broadcom/bgmac.c index 1835266fdd09..7079228e70c0 100644 --- a/drivers/net/ethernet/broadcom/bgmac.c +++ b/drivers/net/ethernet/broadcom/bgmac.c @@ -1415,11 +1415,15 @@ void bgmac_adjust_link(struct net_device *net_dev) { struct bgmac *bgmac = netdev_priv(net_dev); struct phy_device *phy_dev = net_dev->phydev; + int speed = phy_dev->speed; bool update = false; + if (bgmac->feature_flags & BGMAC_FEAT_FORCE_SPEED_2500) + speed = SPEED_2500; + if (phy_dev->link) { - if (phy_dev->speed != bgmac->mac_speed) { - bgmac->mac_speed = phy_dev->speed; + if (speed != bgmac->mac_speed) { + bgmac->mac_speed = speed; update = true; } -- 2.53.0