Date: Wed, 29 Oct 2014 18:29:37 +0100 From: Bernd Walter <ticso@cicely7.cicely.de> To: Luiz Otavio O Souza <lists.br@gmail.com> Cc: Andreas Schwarz <Andreas.Schwarz@schwarzes.net>, George Rosamond <george@ceetonetechnology.com>, "freebsd-arm@freebsd.org" <freebsd-arm@freebsd.org>, ticso@cicely.de, Tim Kientzle <tim@kientzle.com> Subject: Re: sd card probing (was: FreeBSD 10.0 on Raspberry PI B+ no network devices Message-ID: <20141029172937.GB59614@cicely7.cicely.de> In-Reply-To: <20141023022244.GB16490@cicely7.cicely.de> References: <20140825163528.d2e696cc3d03ad9bebcd239c@schwarzes.net> <20140826074951.4cf5a8fc@X220.alogt.com> <53FD1646.2010103@ceetonetechnology.com> <20140827021349.1273f703c6756d07fad72a16@schwarzes.net> <20141014032743.GK38905@cicely7.cicely.de> <20141014041305.GM38905@cicely7.cicely.de> <CAB=2f8wiBLRYBVHUw-PptzQE-QP3%2B1EmHFMMMipZWi_dUG9m8w@mail.gmail.com> <20141022204454.GA12231@cicely7.cicely.de> <CAB=2f8xHEeF8DtP1eCkpp3Y0rZu3w0Phi_gzMSByGJ74xaFchg@mail.gmail.com> <20141023022244.GB16490@cicely7.cicely.de>
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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: > > >> > > > >> > Ok - that card problem seems random or contact related. > > >> > Whatever, it is 6 am - time to sleep ;-) > > >> > > >> I've found a missing silicon bug workaround on our driver. > > >> > > >> It's pretty recent and i'm still building new images to test with more > > >> cards, but it did fix all the instability i was seeing on the > > >> identification of one of my cards. > > >> > > >> Together with the new firmware (yes, there is another SD fix there) my > > >> RPi B rev 2 (with this same card) has gone from unusable to rock > > >> stable (i've done 80 cold boots without any damage/corruption to the > > >> card). > > >> > > >> Please, give it a try and let me know if it helps. > > > > > > Tested. > > > All I can say so far is that it is random, but your patch didn't help. > > > > Without my patch you should see the speed and the bus width changing > > over the boots and with my patch it should always be the same > > (41.6MHz/4bit): > > > mmcsd0: 8GB <SDHC 00000 1.0 SN 62A50A6C MFG 11/2013 by 27 SM> at mmc0 41.6MHz/4bit/65535-block > > > > > Furthermore this problem now happens on each boot try. > > > It still may be possible that it can boot, but I've tried many more > > > times than needed before. > > > > > > Timecounters tick every 10.000 msec > > > usbus0: 480Mbps High Speed USB v2.0 > > > ugen0.1: <DWCOTG> at usbus0 > > > uhub0: <DWCOTG OTG Root HUB, class 9/0, rev 2.00/1.00, addr 1> on usbus0 > > > mmcsd0: 8GB <SDHC 00000 1.0 SN 62A50A6C MFG 11/2013 by 27 SM> at mmc0 41.6MHz/4bit/65535-block > > > mmcsd0: Error indicated: 1 Timeout > > > mmcsd0: Error indicated: 1 Timeout > > > fb0: 656x416(0x0@0,0) 16bpp > > > fb0: pitch 1312, base 0x5e006000, screen_size 545792 > > > fbd0 on fb0 > > > VT: initialize with new VT driver "fb". > > > > Ok. Can you try add the following to /boot/loader.conf ? > > > > echo hw.bcm2835.sdhci.hs=0 >> /boot/loader.conf > > > > RPi _is_ picky about the SD card, the patch won't make that go away > > but should help in a few cases. > > I know - that's the reason why I bought the B+ boards in bundle with > cards directly from Farnell. > Hoped they wouldn't make any problems under FreeBSD. > The cards unfortunately are unlabeled, just the included SD adapter > has a raspi logo. > > > There is a possibility that your card won't work in HS mode and now > > that the card identification always works, it will always go with the > > highest supported speed. The tunable should help if that is the case. > > This makes sense. > I don't remember this card/board combination, but about a year ago, when > I used other cards in other boards the speed and width wasn't always the > same. > > And you are absolutely right, with that loader.conf entry it works. > ... > mmcsd0: 8GB <SDHC 00000 1.0 SN 62A50A6C MFG 11/2013 by 27 SM> at mmc0 25.0MHz/4bit/65535-block > ... This is another card from the same order (and hopefully same batch) in a Beaglebone Black: mmcsd0: 8GB <SDHC 00000 1.0 SN A2050A45 MFG 11/2013 by 27 SM> at mmc0 48.0MHz/4bit/65535-block Interesting that the Raspberry is so picky about them, since the card clearly is capable to do such frequency. But I miss something on the Raspberry board. The B boards clearly have series resistors in the signal lines. The B+ has not. However the MMC/SD should have some pull up resistors, usually around 100k Ohms. Following the signals is hard to impossible, but there are no such resistors in a reasonable location on neither B nor B+. They might be interal in the broadcom SoC, but this is very unusual. I consider modding the SD signals on the B+ impossible, but it can be done on the B. -- B.Walter <bernd@bwct.de> http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.
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