On Aug 6, 2009, at 4:32 PM, Gilles Chanteperdrix wrote: > The Geode is a very very bad choice: > - it is going to disappear any time soon > - its performances in many domains are far from the average x86 > performances.
Agreed. > > Ok. I guess your Geode does not have an APIC. I have a Geode and just > checked, it has the same issue, so, you should turn of apic in kernel > configuration. Maybe something is needed in the BIOS to enable it > (because the AMD specs say that the Geode has an APIC). I've also tried to figure out how to get it to work with both a GX1 and an LX-800 and cannot get it to work. I have read on other lists that there is no APIC. > Probably an issue induced by power management disabling the tsc. So > the > usual advices apply, please be sure to disable any smart power > management issue in the bios configuration and to boot with ACPI > enabled > (except ACPI_PROCESSOR). Someone, a long time ago, posted on the RTAI > mailing list a way to disable this tsc thing by running an outb at a > well defined address, but I never was able to test it since my Geode > does not have this issue. Another workaround reported to work is to > boot > with idle=poll passed on the command line. Yet another workaround is > to > avoid using the tsc (by selecting in the kernel configuration a > processor without tsc), but this means a lot of overhead. We use TSC with idle=poll and things work correctly. However, the power saving mode will not run. However, gx1 is efficient and does not require a heatsink or fan, so it will not hurt your hardware. If you are running off a battery then you might want to use another approach. The big issue with geode is the SMI overhead. It's terrible, and it will be a thorn in your side as you try to minimize jitter. I suggest you consider another board. Someday when I get some time, I may try and look into an smi disable function for geode. I think Gilles was going to look into it at some point, too. I've not really had a chance to work with Xenomai since May as the company I assist part time has been working on other things lately. Steven _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
