From owner-p4-projects@FreeBSD.ORG Sat Feb 16 22:31:49 2008 Return-Path: Delivered-To: p4-projects@freebsd.org Received: by hub.freebsd.org (Postfix, from userid 32767) id 8B47816A469; Sat, 16 Feb 2008 22:31:49 +0000 (UTC) Delivered-To: perforce@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 43BDA16A420; Sat, 16 Feb 2008 22:31:49 +0000 (UTC) (envelope-from xcllnt@mac.com) Received: from smtpoutm.mac.com (smtpoutm.mac.com [17.148.16.75]) by mx1.freebsd.org (Postfix) with ESMTP id 1DC0413C455; Sat, 16 Feb 2008 22:31:49 +0000 (UTC) (envelope-from xcllnt@mac.com) Received: from mac.com (asmtp007-s [10.150.69.70]) by smtpoutm.mac.com (Xserve/smtpout012/MantshX 4.0) with ESMTP id m1GMVms1027490; Sat, 16 Feb 2008 14:31:49 -0800 (PST) Received: from macbook-pro.jnpr.net (natint3.juniper.net [66.129.224.36]) (authenticated bits=0) by mac.com (Xserve/asmtp007/MantshX 4.0) with ESMTP id m1GMVlEl022025 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Sat, 16 Feb 2008 14:31:47 -0800 (PST) Message-Id: <504560A3-EABB-4896-8B3E-C7FC89F31EFB@mac.com> From: Marcel Moolenaar To: Rafal Jaworowski In-Reply-To: <47B75EB3.2020001@semihalf.com> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v919.2) Date: Sat, 16 Feb 2008 14:31:47 -0800 References: <200802162141.m1GLfgkj048217@repoman.freebsd.org> <47B75EB3.2020001@semihalf.com> X-Mailer: Apple Mail (2.919.2) Cc: Marcel Moolenaar , Perforce Change Reviews Subject: Re: PERFORCE change 135517 for review X-BeenThere: p4-projects@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: p4 projects tree changes List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 16 Feb 2008 22:31:49 -0000 On Feb 16, 2008, at 2:07 PM, Rafal Jaworowski wrote: > Marcel Moolenaar wrote: >> http://perforce.freebsd.org/chv.cgi?CH=135517 >> >> Change 135517 by marcel@marcel_jnpr on 2008/02/16 21:41:02 >> >> Save U-Boot's registers at startup and restore them when >> performing a syscall. This way we don't have to compile >> code specially to avoid using those registers. Otherwise >> we have to encode knowledge of those registers in at least >> 4 makefiles and introduce a build knob to enable it all. >> This does not allow us to build everything with a single >> build world. >> > > Hi Marcel, > > I'm not quite sure this is sufficient... I already had a similar > save/restore > in place, but there is some general problem with U-Boot that leads > to hangs > (experienced): Interesting, I didn't see any such problems with 1.3.2-rc1. > - U-Boot does not handle interrupts so there's no context save/ > restore of > exceptions, other than very few cases > > - there's one paricular asynchronous way for U-Boot code to regain > control > without those dedicated r14/29 regs saved: decrementer, which can > hit anytime > while in the app code, and which usually leads to hangs/corruption > as U-Boot > code use them blindly It's really best if U-Boot deals with that. > PS. I guess it would be good to synchronise somehow the work, as we > seem to > tackle the same pieces, which is a waste of resources. Yes, definitely... -- Marcel Moolenaar xcllnt@mac.com