From owner-freebsd-arm@FreeBSD.ORG Tue May 20 04:13:31 2014 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 278E1436 for ; Tue, 20 May 2014 04:13:31 +0000 (UTC) Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id E907A28A7 for ; Tue, 20 May 2014 04:13:30 +0000 (UTC) Received: by mail-pa0-f49.google.com with SMTP id lj1so6658213pab.36 for ; Mon, 19 May 2014 21:13:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:content-type:mime-version:subject:from :in-reply-to:date:cc:message-id:references:to; bh=A2YnWwXv9cq2lfscCYA1J0pAogQPrGlemCzxq33bU6c=; b=TxNMaU7K4A74PgH53WiTeMiDjL9a/5uoX2DhtysCLoOctRDhCCOOChUCVX4mCTXlCF icxZaulp0gAyvpFpNLADj9xqXOd1DP+jLjyIyEVCyJci9KcJarAgTmcGvJb03m7KTrMW pwipRXNPXFLv9l9t9d39y2h7lJwzkz0RS5+EanDhv03njNO5maei3mD8UUU0cxu3bZe7 GQUQPXwD+STzOeaWq/CB89KKRZ6Z9vDmEq2GZxV0N/4jG+Gllc8lLURp8YYc+MWqPxK/ 72uHdRkDjpy07nxakzi7Dzw/nC7hTHgTtXx5igxU08PBTvMUOHHJ4Izy13lJ7VqZgJuJ PtRg== X-Gm-Message-State: ALoCoQnY1lIGMfX2UFcJ32vtoepg4aDlPU+O1PY+jB8ltp/TdWzgHWMEzUlMh5GlaZ8tPWT6LfJI X-Received: by 10.67.29.204 with SMTP id jy12mr8279117pad.37.1400558879422; Mon, 19 May 2014 21:07:59 -0700 (PDT) Received: from [10.64.26.239] (dc1-prod.netflix.com. [69.53.236.251]) by mx.google.com with ESMTPSA id gu11sm498532pbd.38.2014.05.19.21.07.53 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 19 May 2014 21:07:53 -0700 (PDT) Sender: Warner Losh Content-Type: multipart/signed; boundary="Apple-Mail=_8B59F4D9-69FC-4DA7-82CB-E9C8F74E21FC"; protocol="application/pgp-signature"; micalg=pgp-sha512 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.2\)) Subject: Re: BBB MMC / SD detection instability with U-Boot 2014.04 (CPU 1GHz) From: Warner Losh In-Reply-To: <537ACDB2.9080808@hot.ee> Date: Mon, 19 May 2014 22:07:52 -0600 Message-Id: References: <537A050E.3040804@hot.ee> <537AB550.2090401@hot.ee> <537AB675.1020006@hot.ee> <024F43EF-E299-413E-AE42-2507AEDD0886@bsdimp.com> <537ACDB2.9080808@hot.ee> To: "Sulev-Madis Silber (ketas)" X-Mailer: Apple Mail (2.1878.2) Cc: freebsd-arm X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 May 2014 04:13:31 -0000 --Apple-Mail=_8B59F4D9-69FC-4DA7-82CB-E9C8F74E21FC Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 On May 19, 2014, at 9:36 PM, Sulev-Madis Silber (ketas) = wrote: > On 2014-05-20 05:39, Winston Smith wrote: >> On Mon, May 19, 2014 at 10:28 PM, Warner Losh wrote: >>> Wow! That=92s a lot of added 10ms delays=85 Do we have a theory of = the crime >>> for why they are needed? Usually they suggest to me that we=92re = doing something >>> wrong (either not checking the right bits in the bridge, having a = fixed retry count >>> rather than a timed limit and having some bridges fail more slowly = than others >>> so the delays are effecting the same thing). >>=20 >> It's a good start (since the BBB is really flakey at 1Ghz), but yes, >> more delays aren't good! >>=20 >> For what it's worth, I'm working in parallel with both FreeBSD and >> Debian Wheezy images on the BBB, and it is quite apparent that the = BBB >> running FreeBSD is *much* slower to boot than the BBB running Debian; >> which currently boots to the login prompt in about 15 seconds from >> power up. FreeBSD has a 15-20 second delay just to detect the eMMC, >> let alone everything else. >>=20 >> Comparatively, my x64 FreeBSD VM boots much more quickly than my = Ubuntu x64 VM. >>=20 >> -W. >>=20 >=20 >=20 > "really flakey" sounds like "unstable, panics 1000 times a day". I = don't > see any of that here (as of 11.0-CURRENT r266442). >=20 > Boot, hmm... yea, 1min (just measured) to fully boot up and connect to > server (I'm using ethernet, DHCP, loader boot delay =3D 3, huge Perl > program) might be too slow if you have some embedded system which > constantly loses power or something... I haven't tried to do any boot > time optimizations yet. Compress kernel? Compress userland? Execute > something in parallel on init (NOTE: *DON'T* even think about porting > Linux init replacements here)? Use rescue-like static binary? Heavily > customize / patch kernel? Use own init? Use rootfs inside kernel? > Actually I guess many people might think like me... "HELL, optimizing > boot time of 1min?! I have more important tasks to do than this=94. Make MMC faster, and a lot of this will go away. When I was doing Atmel, I got more milage out of optimizing the I/O path for slow boots than I = did for just about anything else. Another quick hack: delete all files in /etc/rc.d that aren=92t used. Warner --Apple-Mail=_8B59F4D9-69FC-4DA7-82CB-E9C8F74E21FC Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQIcBAEBCgAGBQJTetUYAAoJEGwc0Sh9sBEASacP/1QMabYYqfMhPsQ0bsMYA9q2 Dkr0JhSeHtp9KeLWMfezjfCYcrhJBJY+VL1RBj50dDXtNyYYXDrUtGL7c1TzhbTp tAXUnVyutwxaD10HSskxA0EVJlPY6wfZxSMdGzT1FI2ZJw1sqzUQEyimwaIWJX4A S/70Ce5SnqSSBsTPwk1d4YHFzd3C7GYHApHQ/NmP5YNgAhAC30h/VY+15HWkM78j K7lUKm9dkbvP+94hOrHoTaq/BuVgXSu1LsthOTzzWa8ZJZHQlddp0kU4deb5DkZM xrW9y2IDopm9LSkBR6cBKYNHouE01nVeO2FLAwf3wVWkdFxS1TLkL5rqcBE1A86F CoJzwI23jXlMqKAd1Bw4ymEnGYTTA3fuUsn9mFUI5PdDGkJakTFp2R/74DQQpxe8 vExAkrOfKUv1U2gp+TyfULuhu4Zhv6anrqpWrCnPo6jyyHFmzlssqydrUTlw4Jtx 2xHzD7kK+ASVNP815+jswtGokQC6onPxiFXKkfWF+ZvuwD0T++BN0c0IJO2Oje7k d0rdPT4JXaptNsJepIH+Rc1tYdQUoqM1EWOjuqLaC4djfZK1IcmQMMf1rM+QyX5V r5p6lY5braH/doSiM2F//hRijPmTAWq6jPwogDDLmtPJ/5c+XPD/08F4bY5ihv// TmRrkfDlQwHJtAnI2eXh =5qoi -----END PGP SIGNATURE----- --Apple-Mail=_8B59F4D9-69FC-4DA7-82CB-E9C8F74E21FC--