From owner-freebsd-arm@FreeBSD.ORG Sat Jan 11 14:00:13 2014 Return-Path: Delivered-To: freebsd-arm@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id AB138921; Sat, 11 Jan 2014 14:00:13 +0000 (UTC) Received: from nibbler.fubar.geek.nz (nibbler.fubar.geek.nz [199.48.134.198]) by mx1.freebsd.org (Postfix) with ESMTP id 8891D14BF; Sat, 11 Jan 2014 14:00:13 +0000 (UTC) Received: from bender.Home (97e07ae8.skybroadband.com [151.224.122.232]) by nibbler.fubar.geek.nz (Postfix) with ESMTPSA id 58D2B5DFFE; Sat, 11 Jan 2014 13:52:02 +0000 (UTC) Date: Sat, 11 Jan 2014 13:51:56 +0000 From: Andrew Turner To: John-Mark Gurney Subject: Re: svn commit: r258412 - in head/sys/arm: at91 econa s3c2xx0 sa11x0 xscale/i80321 xscale/i8134x xscale/ixp425 xscale/pxa Message-ID: <20140111135156.251a70fa@bender.Home> In-Reply-To: <20140110230241.GS46596@funkthat.com> References: <201311210108.rAL18AoQ051365@svn.freebsd.org> <20131221061048.GC99167@funkthat.com> <20140108071643.GB99167@funkthat.com> <1389197091.1158.370.camel@revolution.hippie.lan> <20140108173909.GF99167@funkthat.com> <20140110230241.GS46596@funkthat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: andrew@FreeBSD.org, freebsd-arm@FreeBSD.org, Ian Lepore X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 11 Jan 2014 14:00:13 -0000 On Fri, 10 Jan 2014 15:02:41 -0800 John-Mark Gurney wrote: > John-Mark Gurney wrote this message on Wed, Jan 08, 2014 at 09:39 > -0800: > > So, I've tested that HEAD (absolutely no tree changes) w/ > > WITHOUT_ARM_EABI boots fine... and just to make sure my test is > > correct, I've disabled it too to verify that the kernel just hangs > > (absolutely no output).. and reenabled it and verified it works > > (that my setting is changing something)... > > worky -> no worky -> worky... > > > > Now I just realized another interesting thing about setting > > WITHOUT_ARM_EABI, it also fixes the console issue I was having w/ > > your call to cpu_setup("") previously (w/ EABI) killing console > > output and not even seeing the mtx panic message... > > > > So, it is clearly changing something very early on in boot... > > Apparently gcc ARMEB w/ EABI miscompiles code... The code to store > lo_flags in the lock_object is correct: > lock->lo_flags = i << LO_CLASSSHIFT; > c03ce2d0: e1a01c06 lsl r1, r6, #24 > c03ce2d4: e5881004 str r1, [r8, #4] > > But when I add a printf to fetch the data, I get: > printf("lo_classindex: %#x\n", LO_CLASSINDEX(lock)); > c03ce2e0: e5d81007 ldrb r1, [r8, #7] > c03ce2e4: e59f0098 ldr r0, [pc, #152] ; c03ce384 > <_end+0xffcf9 > 19c> > c03ce2e8: e201100f and r1, r1, #15 ; 0xf > c03ce2ec: eb0012ea bl c03d2e9c > > > We are doing a ldrb (LoaD Relative Byte) which would be fine to > substitute for the right shift of 24, but only if it loaded the > correct byte.. It should be loading #4 instead of #7 since we are on > big endian... > > Anyone who know gcc arm well to figure this out? > I have an untested fix at [1]. As I don't have any big-endian boards I am unable to test the kernel with this. Andrew [1] http://people.freebsd.org/~andrew/armeb_gcc.diff