From owner-freebsd-arm@FreeBSD.ORG Wed Oct 29 21:27:21 2014 Return-Path: Delivered-To: freebsd-arm@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 38A4D375 for ; Wed, 29 Oct 2014 21:27:21 +0000 (UTC) Received: from mho-01-ewr.mailhop.org (mho-03-ewr.mailhop.org [204.13.248.66]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 043E29C7 for ; Wed, 29 Oct 2014 21:27:19 +0000 (UTC) Received: from [73.34.117.227] (helo=ilsoft.org) by mho-01-ewr.mailhop.org with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.72) (envelope-from ) id 1Xjaly-000CgX-K3; Wed, 29 Oct 2014 21:27:18 +0000 Received: from [172.22.42.240] (revolution.hippie.lan [172.22.42.240]) by ilsoft.org (8.14.9/8.14.9) with ESMTP id s9TLRG8g081542; Wed, 29 Oct 2014 15:27:16 -0600 (MDT) (envelope-from ian@FreeBSD.org) X-Mail-Handler: Dyn Standard SMTP by Dyn X-Originating-IP: 73.34.117.227 X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX1/K8tl1YfNlfa0+Bbn9e/X2 X-Authentication-Warning: paranoia.hippie.lan: Host revolution.hippie.lan [172.22.42.240] claimed to be [172.22.42.240] Subject: Re: sd card probing (was: FreeBSD 10.0 on Raspberry PI B+ no network devices From: Ian Lepore To: Warner Losh In-Reply-To: <6CC5D29F-C3F7-4913-9D77-D275EEDDC1DD@bsdimp.com> References: <53FD1646.2010103@ceetonetechnology.com> <20140827021349.1273f703c6756d07fad72a16@schwarzes.net> <20141014032743.GK38905@cicely7.cicely.de> <20141014041305.GM38905@cicely7.cicely.de> <20141022204454.GA12231@cicely7.cicely.de> <20141023022244.GB16490@cicely7.cicely.de> <20141029172937.GB59614@cicely7.cicely.de> <1414605501.17308.97.camel@revolution.hippie.lan> <20141029200403.GC59614@cicely7.cicely.de> <1414613786.17308.124.camel@revolution.hippie.lan> <6CC5D29F-C3F7-4913-9D77-D275EEDDC1DD@bsdimp.com> Content-Type: text/plain; charset="us-ascii" Date: Wed, 29 Oct 2014 15:27:16 -0600 Message-ID: <1414618036.17308.146.camel@revolution.hippie.lan> Mime-Version: 1.0 X-Mailer: Evolution 2.32.1 FreeBSD GNOME Team Port Content-Transfer-Encoding: 7bit Cc: "freebsd-arm@freebsd.org" , ticso@cicely.de X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Oct 2014 21:27:21 -0000 On Wed, 2014-10-29 at 14:59 -0600, Warner Losh wrote: > On Oct 29, 2014, at 2:16 PM, Ian Lepore wrote: > > > On Wed, 2014-10-29 at 21:04 +0100, Bernd Walter wrote: > >> On Wed, Oct 29, 2014 at 11:58:21AM -0600, Ian Lepore wrote: > >>> On Wed, 2014-10-29 at 18:29 +0100, Bernd Walter wrote: > >>>> On Thu, Oct 23, 2014 at 04:22:44AM +0200, Bernd Walter wrote: > >>>>> On Wed, Oct 22, 2014 at 11:43:01PM -0200, Luiz Otavio O Souza wrote: > >>>>>> On 22 October 2014 18:44, Bernd Walter wrote: > >>>>>>> On Tue, Oct 14, 2014 at 12:51:50PM -0300, Luiz Otavio O Souza wrote: > >>>>>>>> On 14 October 2014 01:13, Bernd Walter wrote: [...] > >>> > >>> Pullups on sd signal lines is a recent thing. It's in the sd 4.x > >>> physical spec, in the form of requiring the standard sd data lines be > >>> pulled high or low when using the new UHS-II signals. Other than that > >>> pullups are not required on any of the lines for sd cards. At work we > >>> don't put pullups on any of them, and use a 22 ohm series on just the > >>> clock line, and that only on designs where we have to fly across a > >>> ribbon cable to get to the card socket. > >> > >> Can't say since when it is in the SD spec, saw it in the MMC, but don't > >> know how long it is there either. > >> Anyway - I remember them well, because I had to hand wire them on my > >> RM9200 prototype boards. > >> It never had been a problem until Warner added higher speed support, but > >> I don't have series resistors on my boards. > > High speed on the RM9200 boards was always a bit dodgy anyway. :( Sorry for the hassle. > Actually high-speed works fine by itself, it's the combo of high-speed and 4-wire that's problematic, because of dma overruns. It's especially bad when usb is also active, because it gets priority on the bus. If the mci dma doesn't get a bus-grant in time, it's not smart enough to stop the clock to the card, and it just looses data instead. All in all, the max reliable data rate is around 3 MB/sec when usb is enabled. -- Ian