From owner-freebsd-arm@FreeBSD.ORG Tue Dec 4 12:12:04 2012 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 40AEADE1 for ; Tue, 4 Dec 2012 12:12:04 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from raven.bwct.de (raven.bwct.de [85.159.14.73]) by mx1.freebsd.org (Postfix) with ESMTP id BDC4E8FC08 for ; Tue, 4 Dec 2012 12:12:03 +0000 (UTC) Received: from mail.cicely.de ([10.1.1.37]) by raven.bwct.de (8.13.4/8.13.4) with ESMTP id qB4BulMh087618 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 4 Dec 2012 12:56:48 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (cicely7.cicely.de [10.1.1.9]) by mail.cicely.de (8.14.5/8.14.4) with ESMTP id qB4BuYDE047846 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 4 Dec 2012 12:56:34 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (localhost [127.0.0.1]) by cicely7.cicely.de (8.14.2/8.14.2) with ESMTP id qB4BuXjp062687; Tue, 4 Dec 2012 12:56:33 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: (from ticso@localhost) by cicely7.cicely.de (8.14.2/8.14.2/Submit) id qB4BuWqZ062686; Tue, 4 Dec 2012 12:56:32 +0100 (CET) (envelope-from ticso) Date: Tue, 4 Dec 2012 12:56:32 +0100 From: Bernd Walter To: Daisuke Aoyama Subject: Re: FreeBSD on Raspberry Pi 512MB (with U-Boot + ubldr) Message-ID: <20121204115631.GA62551@cicely7.cicely.de> References: <3988C1622A974F19A9D3888F0334FF10@ad.peach.ne.jp> <50B8058C.9030909@bluezbox.com> <18DB98C9-66D9-4B00-989A-156F21E9981C@bsdimp.com> <1354552432.1140.28.camel@revolution.hippie.lan> <797FC9C0D52846548418B1E8F70A0402@ad.peach.ne.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <797FC9C0D52846548418B1E8F70A0402@ad.peach.ne.jp> X-Operating-System: FreeBSD cicely7.cicely.de 7.0-STABLE i386 User-Agent: Mutt/1.5.11 X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED=-1, BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 autolearn=unavailable version=3.3.0 X-Spam-Checker-Version: SpamAssassin 3.3.0 (2010-01-18) on spamd.cicely.de Cc: freebsd-arm@freebsd.org, Ralf.Wenk@hs-karlsruhe.de X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list Reply-To: ticso@cicely.de List-Id: Porting FreeBSD to the StrongARM Processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Dec 2012 12:12:04 -0000 On Tue, Dec 04, 2012 at 02:43:23AM +0900, Daisuke Aoyama wrote: > >SD 2.0 upped the limit to 50mhz, but you can't set the bus to run that > >fast until you've probed the card and determined that it supports SDHC. > >The signaling standard is actually different between 1.x and 2.x in SDHC > >mode (there are differences in the relationships between rise/fall/hold > >times above 25mhz). That's why old Atmel hardware can't do SDHC 50mhz > >even though the microcontroller can run the bus at 50mhz -- it does so > >with the 1.x signal timings (it was pretty sneaky of them to adverise > >mmc/sd up to 50mhz knowing that running the bus that fast was just a > >violation of the SD 1.x spec, which is all they really support). With AT91RM9200 the problem was noticeable because typically you run the peripheral clock at 60MHz, so you can divide to 15MHz or 30MHz, which was too high for standard, but usually worked well with most cards. > >I've heard that SD 3.x allows for bus speeds of 100mhz and higher, but > >only on SDXC cards. I'm hand-waving a bit here because I haven't gotten > >to work with hardware that new yet. > > Yes, you are right. But my card don't work with 50/100MHz 4bit mode. > And, many users have reported don't work. > In my case, the command under 50/100 was reported CRC error, etc. > > FYI, the cards require 2x max power consumption when HS mode is enabled. > There is another factor the card runs at HS on RPI. > I imagine my card eats more power :) The power design of the RPI is one of the points I don't like. > >Bus speed is independant of the 1/4/8 bit datapath (well, at least in > >the SD specs up through 2.0, after that I'm not sure). > > AFAIK, micro SD cards use 1bit. MicroSD also have 4-bit - same number of contacts. Support for it always had been optional, that's the reason why it must be probed and activated first. MicroSD must support 1-bit SPI mode, which is optional on standard size SD, but since they share common chips SD cards usually can do SPI as well. -- B.Walter http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.