On Thu, 2007-03-15 at 15:21 -0500, Jeff Weber wrote: > I found the advisory against using the HPET timer in the wiki FAQ, and > disabled both > CONFIG_HPET_TIMER > CONFIG_HPET_EMULATE_RTC > > in my kernel config. Now I am having intermittent faults reading the TSC on > my x86 CPU. > Occasionally, reads of the TSC go backwards. The tracer also shows one of my > Xenomai > kernel threads going into an infinite loop reading the TSC: > > :| +*end 0xffffff05 -798 0.675 common_interrupt+0x34 > (do_gettimeofday+0x59) > : +*func -797 0.585 get_offset_tsc+0x8 > (do_gettimeofday+0x2a) > : +*func -797 0.571 get_offset_tsc+0x8 > (do_gettimeofday+0x2a) > : +*func -796 0.496 get_offset_tsc+0x8 > (do_gettimeofday+0x2a) > ... > ad infinitum > > This behavior runs contrary to all the Xenomai configuration advice. I would > like > to keep the HPET timer disabled so I can eventually upgrade to Xenomai-2.3. > > Any idea on what's happining with my HPET timer? >
Not yet. I still don't find anything in the HPET support code that would particularly confuse the I-pipe, but nonetheless, it has been reported that CONFIG_HPET_TIMER did break some configurations when enabled. I still need to check this on proper hardware and find out why. > config: > linux-2.6.17.14 > ipipe-1.5-00 > xenomai-2.2.4 > cpu = VIA Nehemiah > flags = fpu vme de pse tsc msr cx8 sep mtrr pge cmov pat mmx fxsr sse up rng > rng_en ace ace_en > motherboard: Hercules EBX > kernel config: > # CONFIG_M586TSC is not set > CONFIG_X86_TSC=y > # CONFIG_HPET_TIMER is not set > > thanks, -- Philippe. _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
