From owner-freebsd-arch@FreeBSD.ORG Wed Jan 25 22:36:04 2012 Return-Path: <owner-freebsd-arch@FreeBSD.ORG> Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DDFC9106566C for <freebsd-arch@freebsd.org>; Wed, 25 Jan 2012 22:36:04 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id 8D4558FC1A for <freebsd-arch@freebsd.org>; Wed, 25 Jan 2012 22:36:04 +0000 (UTC) Received: from [10.30.101.53] ([209.117.142.2]) (authenticated bits=0) by harmony.bsdimp.com (8.14.4/8.14.3) with ESMTP id q0PMSiC4015460 (version=TLSv1/SSLv3 cipher=DHE-DSS-AES128-SHA bits=128 verify=NO); Wed, 25 Jan 2012 15:28:45 -0700 (MST) (envelope-from imp@bsdimp.com) Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii From: Warner Losh <imp@bsdimp.com> In-Reply-To: <20120125221753.GA17821@alchemy.franken.de> Date: Wed, 25 Jan 2012 15:28:38 -0700 Content-Transfer-Encoding: quoted-printable Message-Id: <EA39C477-1B2D-4CE4-B146-4D2E16603170@bsdimp.com> References: <47ABA638-7E08-4350-A03C-3D4A23BF2D7E@lassitu.de> <1763C3FF-1EA0-4DC0-891D-63816EBF4A04@lassitu.de> <20120106182756.GA88161@alchemy.franken.de> <95372FB3-406F-46C2-8684-4FDB672D9FCF@lassitu.de> <20120106214741.GB88161@alchemy.franken.de> <F60B2B70-049F-4497-BBA8-3C421088C1EA@lassitu.de> <20120108130039.GG88161@alchemy.franken.de> <23477898-8D85-498C-8E30-192810BD68A8@lassitu.de> <20120111193738.GB44286@alchemy.franken.de> <66DDA0A2-F878-43FF-8824-54868F493B18@lassitu.de> <20120125221753.GA17821@alchemy.franken.de> To: Marius Strobl <marius@alchemy.franken.de> X-Mailer: Apple Mail (2.1084) X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0.1 (harmony.bsdimp.com [10.0.0.6]); Wed, 25 Jan 2012 15:28:46 -0700 (MST) Cc: Stefan Bethke <stb@lassitu.de>, FreeBSD-arch <freebsd-arch@freebsd.org> Subject: Re: Extending sys/dev/mii X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture <freebsd-arch.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>, <mailto:freebsd-arch-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arch> List-Post: <mailto:freebsd-arch@freebsd.org> List-Help: <mailto:freebsd-arch-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>, <mailto:freebsd-arch-request@freebsd.org?subject=subscribe> X-List-Received-Date: Wed, 25 Jan 2012 22:36:04 -0000 On Jan 25, 2012, at 3:17 PM, Marius Strobl wrote: > Yes, architecture of newbus is built around the assumption that > there's a single device tree and all you ever need are child- > parent-relationships. AFAICT this assumption dates back to at > least the device configuration in 4.4BSD and apart from the > embedded world it held true just fine so far ... Even in the embedded world it is true. The problem is that in the = embedded world multiple devices use the service of another device which = is why we're seeing teething pain with the MDIO bus (which shares all = the management lines between the PHY rather than having each MAC have = its own connection to the PHY). So while the basic resources are still = hierarchical, the interconnects have become more complicated. The issue = we're facing here is that we'd assumed that the MAC PHY connection could = provide management services since you knew you had to have data services = or else you'd have no packet flow... We're seeing the same struggles with gpio and interrupt pins... Warner