From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicola Salvemini Date: Fri, 29 Feb 2008 15:07:08 +0000 (GMT) Subject: [Buildroot] Problem with iperf Message-ID: <185940.75390.qm@web23411.mail.ird.yahoo.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Hi Rex, thanks for your advice! This was helpful. I tried to use 'make clean' command to clean buildroot but, obviously, it was not appropriate! However I have now another problem. After some iteration, iperf stops with some TX underrun ethernet errors: eth0: TX underrun, resetting buffer After a brief research I understood that this is a know problem for AT91SAM9260 processor (https://linuxlink.timesys.com/forum/2119), and I'm trying for resolve it. Thank you very much for your help, best regards, Nicola. ----- Messaggio originale ----- Da: Rex Ashbaugh A: Nicola Salvemini Cc: buildroot at uclibc.org Inviato: Gioved? 28 febbraio 2008, 18:21:31 Oggetto: Re: [Buildroot] Problem with iperf hmm, looks like "_udivsi3_s.o" (built with hardware FP) was built prior to your new configuration selection of software FP. you may need to clean buildroot, or start over. just in case, my suggestion is you probably want to preserve the buildroot directory you have, then start a new test buildroot directory and use the correct FP config to see if this will prevent the error below. On 2/28/08, Nicola Salvemini wrote:Yes, I tried to select option "Use software floating point by default" from buildroot configuration menu, but I have some compilation problems: /home/user/buildroot/build_arm/staging_dir/usr/arm-linux-uclibc/bin/ld: ERROR: libgcc/./_udivsi3_s.o uses hardware FP, whereas ./libgcc_s.so.1.tmp uses software FP /home/user/buildroot/build_arm/staging_dir/usr/arm-linux-uclibc/bin/ld: failed to merge target specific data of file libgcc/./_udivsi3_s.o /home/user/buildroot/build_arm/staging_dir/usr/arm-linux-uclibc/bin/ld: ERROR: libgcc/./_divsi3_s.o uses hardware FP, whereas ./libgcc_s.so.1.tmp uses software FP /home/user/buildroot/build_arm/staging_dir/usr/arm-linux-uclibc/bin/ld: failed to merge target specific data of file libgcc/./_divsi3_s.o .... etcetera... Best regards, Nicola. ----- Messaggio originale ----- Da: Rex Ashbaugh A: Nicola Salvemini Cc: buildroot at uclibc.org Inviato: Gioved? 28 febbraio 2008, 16:33:19 Oggetto: Re: [Buildroot] Problem with iperf Also, check how your cross compiler is configured for floating point handling.. http://www.arm.linux.org.uk/mailinglists/faq.php 3. I feel really confused about what's the difference with gcc soft-float support and the kernel NWFPE/FastFPE support? [31 January 2004 - np] Scenario 1 (hard-float): The compiler emits opcodes designed to be used with a hardware floating point coprocessor (FPU). The FPU usually has a set of extra registers for its use, and the compiler may as well pass floating point argument to functions through those registers. This is of course the best performing solution when a real hardware FPU is used. Scenario 2 (soft-float): the compiler converts floating point operations into function calls and a special library is used to provide all functions performing the required operations, all in software with no FPU instructions at all. There is obviously no extra floating point registers available in this case, therefore all FP arguments to functions have to be passed through standard registers or on the stack. This is of course the best performing solution when no hardware FPU is available, given that the library implementing the FP operations is optimally coded. Now, unfortunately, the default on ARM Linux has traditionally been set to have the compiler use hard-float, even if ARM Linux never ran on any ARM CPU with a real hardware FPU. The CPU is therefore raising the invalid instruction exception each time some FPU opcode is encountered. Then the kernel traps that exception, looks at the given FPU instruction and emulates it in software. But here not only the kernel must perform the FP operation, it must emulates the whole hardware FPU as well. That's what NWFPE or FastFPE are doing. This is obviously the worst performing arrangement that can be due to the exception trap and emulation overhead On 2/28/08, Nicola Salvemini wrote:Hi Rex, Yes I tried with the previous version (2.0.1) of iperf, bat I had same results. I'm waiting for a replay from iperf maintainer.. Best regards, Nicola. ----- Messaggio originale ----- Da: Rex Ashbaugh A: Nicola Salvemini Cc: buildroot at uclibc.org Inviato: Mercoled? 27 febbraio 2008, 16:52:03 Oggetto: Re: [Buildroot] Problem with iperf NWFPE is the floating point emulator. 00000002 is a floating point divide-by-zero. try another version of iperf maybe? report this problem to the iperf maintainer? -Rex On 2/27/08, Nicola Salvemini wrote:Hi all, I have a ARM arm926t (it's a little-endian) target platform and I use buildroot to cross-compile applications. I include iperf in the package selection for the target and the build phase go to the end without problems, but when I try to use iperf on the target, I take an exception: NWFPE: iperf[770] takes exception 00000002 at c00288f0 from 400f4580 NWFPE: iperf[770] takes exception 00000002 at c00288f0 from 400f4580 NWFPE: iperf[770] takes exception 00000002 at c00288f0 from 400f4580 Could you please give me an idea to resolve the problem? Thanks in advance, Nicola. ___________________________________ L'email della prossima generazione? Puoi averla con la nuova Yahoo! Mail: http://it.docs.yahoo.com/nowyoucan.html _______________________________________________ buildroot mailing list buildroot at uclibc.org http://busybox.net/mailman/listinfo/buildroot L'email della prossima generazione? Puoi averla con la nuova Yahoo! Mail L'email della prossima generazione? Puoi averla con la nuova Yahoo! Mail ___________________________________ L'email della prossima generazione? 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