From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20489 invoked by alias); 5 Mar 2012 10:16:52 -0000 Received: (qmail 20477 invoked by uid 22791); 5 Mar 2012 10:16:50 -0000 X-SWARE-Spam-Status: No, hits=-1.2 required=5.0 tests=AWL,BAYES_00,SARE_LWSHORTT X-Spam-Check-By: sourceware.org Received: from tirion.supremecenter202.com (HELO tirion.supremecenter202.com) (209.25.195.243) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 05 Mar 2012 10:16:37 +0000 Received: from c-32d8e155.355-1-64736c10.cust.bredbandsbolaget.se ([85.225.216.50]:48145 helo=[192.168.0.115]) by tirion.supremecenter202.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from ) id 1S4Uy0-0000wg-2l; Mon, 05 Mar 2012 10:16:32 +0000 Message-ID: <4F549276.7050600@siva.com.mk> Date: Mon, 05 Mar 2012 10:16:00 -0000 From: Ilija Kocho User-Agent: Mozilla/5.0 (X11; Linux i686; rv:10.0) Gecko/20120130 Thunderbird/10.0 MIME-Version: 1.0 To: John Dallaway CC: Tomas Frydrych , ecos-devel@ecos.sourceware.org Subject: Re: eCos GNU tools 4.6.2-20120125 ready for testing References: <4F106345.4080902@siva.com.mk> <4F11574D.9070002@dallaway.org.uk> <4F11AC54.7000902@siva.com.mk> <4F1CB41C.90900@jifvik.org> <4F1DA9A0.5070702@siva.com.mk> <4F1FF5AD.4010901@ecoscentric.com> <4F39887A.5050905@siva.com.mk> <4F50F700.5080902@ecoscentric.com> <4F521D6A.4010500@siva.com.mk> <4F52B2C8.4010809@schuilenburg.org> <4F53C46B.4090502@dallaway.org.uk> <4F54798C.2070700@r-finger.com> <4F547FBE.8080507@r-finger.com> <4F548C37.2090306@dallaway.org.uk> In-Reply-To: <4F548C37.2090306@dallaway.org.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact ecos-devel-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-devel-owner@ecos.sourceware.org X-SW-Source: 2012-03/txt/msg00013.txt.bz2 On 05.03.2012 10:49, John Dallaway wrote: > Hi Tomas > > Tomas Frydrych wrote: > >> On 05/03/12 08:30, Tomas Frydrych wrote: >>> On 04/03/12 19:37, John Dallaway wrote: >>>> However, this success was achieved using arm-eabi-gdb 6.8.50.20080706. >>>> There does appear to be an issue with the length of the 'g' packet when >>>> using the new arm-eabi-gdb 7.3.1: >>>> >>>>> (gdb) tar rem /dev/ttyS0 >>>>> Remote debugging using /dev/ttyS0 >>>>> Remote 'g' packet reply is too long: e14e000810000000000000001000000000000000000000000000000000000000000000000000000000000000fccf0d6800000000e8cf0d6895680008e24e00080000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000021 >>>>> (gdb) >>>> We will need to look into why the packet length has apparently changed >>>> for Cortex-M targets. I can connect to an ARM7 target using the new GDB >>>> without problem. >>> This is a mismatch between the number of registers a gdb server reports >>> and the number that gdb expects for the given architecture. In this case >>> too many registers are being reported. IIRC, there should be 8 hex >>> digits for a register, so the above string seems to represent 42 >>> registers instead of the 21 that Cortex-M has. Looks like a bug in the >>> monitor stub code, or perhaps a work around for something broken in >>> older toolchains? >> Done bit further digging around the sources, >> hal/cortexm/arch/.../cortexm_stub.h:64 defines 16 gpr, 8 fp or 12 bytes >> each and 2 ps registers; this adds up to the 336 bytes of the above output. > Yes. It looks like the FPA registers have been dropped from the default > register set for Cortex-M targets in recent GDB. In the longer term, we > should add a CDL option to our GDB stub code to accommodate this change. > In the short term, I will look at creating a GDB target description file > that we can use to accommodate the larger register set returned by our > stubs. Could the reason for this be because Cortex-M(4) uses VFP architecture rather than FPA? The FPU used on Cortex-M4 is FPv4-SP-d16 http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0439c/BEHFGGGE.html Ilija