On 2013-06-22 13:57, Franz Engel wrote: > Franz Engel wrote: >> Jan Kiszkas wrote: >>> Franz Engel wrote: >>> Hi, >>> >>> In my dmesg I get the following message: >>> dmesg | grep -i xeno >>> [ 4.478964] I-pipe: head domain Xenomai registered. >>> [ 4.494089] Xenomai: hal/x86_64 started. >>> [ 4.505969] Xenomai: scheduling class idle registered. >>> [ 4.521300] Xenomai: scheduling class rt registered. >>> [ 4.538525] Xenomai: real-time nucleus v2.6.2.1 (Day At The Beach) >> loaded. >>> [ 4.559065] Xenomai: debug mode enabled. >>> [ 4.579351] Xenomai: SMI-enabled chipset found >>> [ 4.592628] Xenomai: SMI workaround failed! >>> [ 4.605677] Xenomai: starting native API services. >>> [ 4.619979] Xenomai: starting POSIX services. >>> [ 4.633088] Xenomai: starting RTDM services. >>> >>> >>> And I have very high latencies. I read that I should try to insert my >> the ID of my LCP into the /usr/src/xenomai/ksrc/arch/x86/smi.c file. >> >> That is no longer true since 2.6.2.1. Xenomai already detects your LPC >> (see above), but the BIOS has apparently locked SMI disabling down. >> >> In this case, you may want to play with smi_mask (see documentation of >> "SMI_EN - SMI Control and Enable Register" in the Intel chipset >> manuals) to see if disabling of individual SMI features work. If not, >> the board is useless for low-latency real-time purposes. > > I found the documentation for my chipset. But I'm not sure with the > interpretation. I think that chapter 13.8.3.11 "SMI_EN-SMI Control and > Enable Register" > (http://www.intel.com/content/dam/doc/datasheet/io-controller-hub-10-family- > datasheet.pdf) is the chapter that descript the options for SMI. But I don't > know how to interpret it. It would be very nice if somebody could look into > and say me how to understand it and how I can use this information to reduce > my latency (if possible).
Try to clear bits 18, 17, 14, 13, 11, 6 and 3. You can also use smictrl [1] for these experiments. Maybe you have to add your chipset in this case (it still uses explicit chipset listings, need to port Xenomai's logic over), but you won't have to reboot for this. Jan [1] http://git.kiszka.org/?p=smictrl.git;a=summary -- Siemens AG, Corporate Technology, CT RTC ITP SES-DE Corporate Competence Center Embedded Linux _______________________________________________ Xenomai mailing list [email protected] http://www.xenomai.org/mailman/listinfo/xenomai
