Re: APU FPU in Virtex ppc405
Shan and I are going to sit down and rebuild our tool chain (a mix of crosstool, linux-from-scratch, and Xilinx patches) next week. Our aim is to quantify the gains/losses of frequency versus hardware acceleration since we have several large scientific apps we plan to run. Like he said, we're hoping to have a handle on the best approach over the next couple of weeks. Ron > My understanding is that with the fpu on the ppc405 (not ppc440), the > processor clock rate had to be reduced for the fpu to work. This ended > up negating much of the performance benefits of using the fpu. > > I don't know the specifics offhand, but Xilinx answer records can be > searched. Hopefully I'm wrong, and there can still be a benefit to using > the ppc405 fpu. > > - John > > > On Thu, 2008-05-22 at 19:06 -0400, David H. Lynch Jr. wrote: > >Were the issues associated with getting the Xilinx Floating point APU > > working with Linux completely resolved ? > > Is there a git tree or patch collection with the appropriate patches > > etc ? > > > > > > > ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
My understanding is that with the fpu on the ppc405 (not ppc440), the processor clock rate had to be reduced for the fpu to work. This ended up negating much of the performance benefits of using the fpu. I don't know the specifics offhand, but Xilinx answer records can be searched. Hopefully I'm wrong, and there can still be a benefit to using the ppc405 fpu. - John On Thu, 2008-05-22 at 19:06 -0400, David H. Lynch Jr. wrote: >Were the issues associated with getting the Xilinx Floating point APU > working with Linux completely resolved ? > Is there a git tree or patch collection with the appropriate patches > etc ? > > > John Bonesio Commercial Linux Solutions [EMAIL PROTECTED] (408) 879-5569 This email and any attachments are intended for the sole use of the named recipient(s) and contain(s) confidential information that may be proprietary, privileged or copyrighted under applicable law. If you are not the intended recipient, do not read, copy, or forward this email message or any attachments. Delete this email message and any attachments immediately. ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
Yes, it's working under Linux. Just do as John, Steve, and Yoshio suggest. That should work then. My problem was that our own cross- tool was not working correctly. But we will fix it in next couple of weeks. I did very primitive changes and didn't have a patch. In next few weeks we might want to go for powerpc tree then, so I will try to do it all over again. Shan On May 22, 2008, at 7:06 PM, David H. Lynch Jr. wrote: Were the issues associated with getting the Xilinx Floating point APU working with Linux completely resolved ? Is there a git tree or patch collection with the appropriate patches etc ? -- Dave Lynch DLA Systems Software Development:Embedded Linux 717.627.3770 [EMAIL PROTECTED] http://www.dlasys.net fax: 1.253.369.9244Cell: 1.717.587.7774 Over 25 years' experience in platforms, languages, and technologies too numerous to list. "Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction." Albert Einstein ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
On Thu, May 22, 2008 at 5:06 PM, David H. Lynch Jr. <[EMAIL PROTECTED]> wrote: > Were the issues associated with getting the Xilinx Floating point APU > working with Linux completely resolved ? >Is there a git tree or patch collection with the appropriate patches > etc ? I had it working at one point ages ago, but that project ended up dropping the work and I haven't touched it since. I think I posted the patches but I don't have a link to them easily at hand. Cheers, g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
APU FPU in Virtex ppc405
Were the issues associated with getting the Xilinx Floating point APU working with Linux completely resolved ? Is there a git tree or patch collection with the appropriate patches etc ? -- Dave Lynch DLA Systems Software Development:Embedded Linux 717.627.3770 [EMAIL PROTECTED] http://www.dlasys.net fax: 1.253.369.9244Cell: 1.717.587.7774 Over 25 years' experience in platforms, languages, and technologies too numerous to list. "Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction." Albert Einstein ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
Hi Thomas, I am still very interested in this. It would be really good if you can post what you have so far. Did you also have to patch gcc also? Is there any penalty in performance when compiling with -fshort-double? /Albert Thomas Werne wrote: > A. Nolson gmail.com> writes: > > >> I have been checking and it seems that the APU FPU patches will give >> some headaches now, so I will probably wait until they merge them with >> the official GCC release. In any case, it seems that the FPU restricts >> the PowerPC and bus frequencies to a max of 200/100. >> >> Anyway, thanks for the info. I will try to keep track of this in case of >> an update. >> >> > > Hi - > > You can get the FPU to work with the 2.6.24rc3 Linux (I got it to work just > yesterday). There are a couple of small changes you have to make to kernel > config files and to one of the .h files, plus you need to compile with the > -fshort-double flag to convert all doubles into floats. Let me know if you're > still interested and I can post details and/or patches. > > Thomas > > -- > Thomas Werne > NASA Jet Propulsion Laboratory > > All personal and professional opinions presented herein are my > own and do not, in any way, represent the opinion or policy of JPL. > > > ___ > Linuxppc-embedded mailing list > Linuxppc-embedded@ozlabs.org > https://ozlabs.org/mailman/listinfo/linuxppc-embedded > > ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
A. Nolson gmail.com> writes: > > I have been checking and it seems that the APU FPU patches will give > some headaches now, so I will probably wait until they merge them with > the official GCC release. In any case, it seems that the FPU restricts > the PowerPC and bus frequencies to a max of 200/100. > > Anyway, thanks for the info. I will try to keep track of this in case of > an update. > Hi - You can get the FPU to work with the 2.6.24rc3 Linux (I got it to work just yesterday). There are a couple of small changes you have to make to kernel config files and to one of the .h files, plus you need to compile with the -fshort-double flag to convert all doubles into floats. Let me know if you're still interested and I can post details and/or patches. Thomas -- Thomas Werne NASA Jet Propulsion Laboratory All personal and professional opinions presented herein are my own and do not, in any way, represent the opinion or policy of JPL. ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
I have been checking and it seems that the APU FPU patches will give some headaches now, so I will probably wait until they merge them with the official GCC release. In any case, it seems that the FPU restricts the PowerPC and bus frequencies to a max of 200/100. Anyway, thanks for the info. I will try to keep track of this in case of an update. Grant Likely wrote: > On Feb 8, 2008 11:51 AM, A. Nolson <[EMAIL PROTECTED]> wrote: > >> Hi, >> >> I have just heard that Xilinx has freed the FPU module for the PPC >> architecture in EDK9.2i. WIll I be able to make it work with my >> Secretlab Linux 2.6.24rc3? Will the eldk toolchain for PPC_4xxfp work? >> Will it be just a matter of integrating it with the XPS BSP?I make an >> extensive use of floating point in my applications and this will be >> really useful. >> > > It's been 2 years since I last played with the FPU core. At the time > it wasn't a complete FPU so the eldk 4xxfp toolchain would not work. > I had to build my own. I don't know if the new core is a complete > implementation. > > Cheers, > g. > > > ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
Re: APU FPU in Virtex ppc405
On Feb 8, 2008 11:51 AM, A. Nolson <[EMAIL PROTECTED]> wrote: > Hi, > > I have just heard that Xilinx has freed the FPU module for the PPC > architecture in EDK9.2i. WIll I be able to make it work with my > Secretlab Linux 2.6.24rc3? Will the eldk toolchain for PPC_4xxfp work? > Will it be just a matter of integrating it with the XPS BSP?I make an > extensive use of floating point in my applications and this will be > really useful. It's been 2 years since I last played with the FPU core. At the time it wasn't a complete FPU so the eldk 4xxfp toolchain would not work. I had to build my own. I don't know if the new core is a complete implementation. Cheers, g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
APU FPU in Virtex ppc405
Hi, I have just heard that Xilinx has freed the FPU module for the PPC architecture in EDK9.2i. WIll I be able to make it work with my Secretlab Linux 2.6.24rc3? Will the eldk toolchain for PPC_4xxfp work? Will it be just a matter of integrating it with the XPS BSP?I make an extensive use of floating point in my applications and this will be really useful. Thanks for your help. ___ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
