From owner-freebsd-arm@FreeBSD.ORG Sat Apr 18 19:42:11 2009 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 888A81065673 for ; Sat, 18 Apr 2009 19:42:11 +0000 (UTC) (envelope-from tinguely@casselton.net) Received: from casselton.net (casselton.net [63.165.140.2]) by mx1.freebsd.org (Postfix) with ESMTP id E7D7D90121 for ; Sat, 18 Apr 2009 19:42:10 +0000 (UTC) (envelope-from tinguely@casselton.net) Received: from casselton.net (localhost [127.0.0.1]) by casselton.net (8.14.3/8.14.3) with ESMTP id n3IJg5CI097494; Sat, 18 Apr 2009 14:42:05 -0500 (CDT) (envelope-from tinguely@casselton.net) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=casselton.net; s=ccnMail; t=1240083725; bh=yWGvcOjc9ofc4umutgMfO/KsTw4M9m0P9sndM9yLGQc=; h=Date:From:Message-Id:To:Subject:Cc:In-Reply-To; b=QHD479DVuAzHFVEIEU9G7s6uq3t4qrVxM+aT/qThhdmnViBLMDLpKr5hgGL/Hrmy5 rk687zkkaOA1O3FAA5RqUw7aXi0IhfxYsOgbqg7Vs0hAN/o9u5tdIpfn/DCrnqoy+Q jjhBG5YQWngHZHHxTae/sgWFsgzPGo+cPi9bpR3E= Received: (from tinguely@localhost) by casselton.net (8.14.3/8.14.2/Submit) id n3IJg5Yi097493; Sat, 18 Apr 2009 14:42:05 -0500 (CDT) (envelope-from tinguely) Date: Sat, 18 Apr 2009 14:42:05 -0500 (CDT) From: Mark Tinguely Message-Id: <200904181942.n3IJg5Yi097493@casselton.net> To: chuckr@telenix.org, tinguely@casselton.net In-Reply-To: <49EA20F4.8080304@telenix.org> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.1.10 (casselton.net [127.0.0.1]); Sat, 18 Apr 2009 14:42:05 -0500 (CDT) Cc: gballet@gmail.com, freebsd-arm@freebsd.org, ticso@cicely.de Subject: Re: Pandora X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting FreeBSD to the StrongARM Processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Apr 2009 19:42:11 -0000 > Mark Tinguely wrote: > > He is not in error talking about previous versions of the ARM. > Didn't want to sound like I was arguing, more like I didn't know, but it flew in > the face of what I'd thought, so I needed to find out. no offense detected nor taken. > OK, then, I'll hunt around for whatever I can find to compare the armv6 with armv7. I just looked at the OMAP glossy doc even says : Fully Software-Compatible With C64x and ARM9. ARM9 is ARMv5. > OTOH, I didn't think of virtual machine usages when I read it, and NOW I've > found a good tech ref for the arm-v7a, so I will know it for sure in a little while. I did not read it too closely. I was mostly interest in the memory management. > I didn't realize that the arm6 was a viable branch-point for implementing other > arm methods. I need to get the tech ref for the arm6, I suppose I'll need to > read them both. IMO, the ARM Architecture Manual is the main reference. > ... from someone who knows VM better than I do, is, or why is, round robin > being used in any Arm? I've been asking various people for 3 years now, and > never gotten any good answer, and it bothers me a lot. There are other people on this list with better ARM arch insight that I; If I remember correctly, the earlier ARM models offered round robin and random cache replacement. My observation is ARM is a RISC arch. I believe the goal is minimize the complexity. For example, adding physically tagged caches requires a longer pipe line; that means branch predictors are added to keep the pipelines full... --Mark.