From owner-freebsd-current@FreeBSD.ORG Thu Dec 20 01:50:43 2007 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2A1DD16A419 for ; Thu, 20 Dec 2007 01:50:43 +0000 (UTC) (envelope-from pyunyh@gmail.com) Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.176]) by mx1.freebsd.org (Postfix) with ESMTP id 03AA613C43E for ; Thu, 20 Dec 2007 01:50:42 +0000 (UTC) (envelope-from pyunyh@gmail.com) Received: by wa-out-1112.google.com with SMTP id k17so5089670waf.3 for ; Wed, 19 Dec 2007 17:50:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:received:received:date:from:to:subject:message-id:reply-to:references:mime-version:content-type:content-disposition:in-reply-to:user-agent; bh=NojJqXgpT+HvvrR4uTxPSbf3jQc2grlmHd+XFUDVmEI=; b=gDEnkScclRBJKKRK+rNdRXYkqPXkYS3ftyDEgBQGsTMpNE4AhTH9k5GLFicS6L8PVV70nWtwYUi7u85x13cgh8W/ETnVKNIodHKjKw5WL4uqWlC8XRRvdTLQZLtXXHywI+vpjZmwCkwT0vgeYzbpfpUNiwttLU4FpU7MGPBSiEM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:subject:message-id:reply-to:references:mime-version:content-type:content-disposition:in-reply-to:user-agent; b=HOqvlzI0AGcYb9KJR8iP7zonJrgGRTxbnuhAjdoAO9ahwiiS3k4Dn4ZygeX71WbHA5P5+9MEp98eB9DvI/sgqxYFOSR1XovOhi9c8ZISSgV/ynAd2EMjm9sji+btnTsWwP9HLD8c3b0oGYjB+83t8UJHT8t0wP4fwWVf5aR9EFM= Received: by 10.114.120.1 with SMTP id s1mr5377926wac.125.1198113943183; Wed, 19 Dec 2007 17:25:43 -0800 (PST) Received: from michelle.cdnetworks.co.kr ( [211.53.35.84]) by mx.google.com with ESMTPS id j21sm1374888wah.2007.12.19.17.25.38 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 19 Dec 2007 17:25:42 -0800 (PST) Received: from michelle.cdnetworks.co.kr (localhost.cdnetworks.co.kr [127.0.0.1]) by michelle.cdnetworks.co.kr (8.13.5/8.13.5) with ESMTP id lBK1PQhO001671 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 20 Dec 2007 10:25:26 +0900 (KST) (envelope-from pyunyh@gmail.com) Received: (from yongari@localhost) by michelle.cdnetworks.co.kr (8.13.5/8.13.5/Submit) id lBK1PMEJ001670; Thu, 20 Dec 2007 10:25:22 +0900 (KST) (envelope-from pyunyh@gmail.com) Date: Thu, 20 Dec 2007 10:25:22 +0900 From: Pyun YongHyeon To: Andrey Chernov , current@freebsd.org Message-ID: <20071220012521.GA993@cdnetworks.co.kr> References: <20071219013343.GA38367@nagual.pp.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071219013343.GA38367@nagual.pp.ru> User-Agent: Mutt/1.4.2.1i Cc: Subject: Re: Question about dev.fxp.0.noflow X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: pyunyh@gmail.com List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 20 Dec 2007 01:50:43 -0000 On Wed, Dec 19, 2007 at 04:33:44AM +0300, Andrey Chernov wrote: > Does anybody know why dev.fxp.0.noflow=1 by default? > Is it more proper to set it to 0? (by default or via /etc/sysctl.conf) > Since flow control is valid only when link partner also agrees on advertised pause capability on full-duplex media, it needs more work in mii/phy driver to advertise correct pause capability. It also needs a way to pass negotiated pause capability back to drvier such that each drvier should program necessary flow control parameters depending on its MAC capability and negociated ones. Just enabling flow control on one side have no effect. I think FreeBSD needs an architectural way to handle flow control in mii layer. Both NetBSD/OpenBSD already supports flow control and marius@ is working on it. Last time I tried his patch seems to work. I don't know when it would hit the tree but I guess it will happen in near future. If we have generic flow control code in mii we can easily add flowcontrol support code to each driver. You may no longer need to set such obscure knob. -- Regards, Pyun YongHyeon