On Sunday 06 November 2005 07:06 am, Vaibhave Agarwal wrote: > hi, > > FreeBSD 6.0 always uses local APIC for the clock. > > But on my Pentium 3, 850 MHz machine, it doesnt detect local APIC and > falls back to using the motherboard clock for the clock interrupts. > > I figured this out by printing the value of > "using_lapic_timer" variable in the sys/i386/isa/clock.c file, > which is always 0. > > But when I use Intel's 3GHz - 64 bit Xeon processor, it detects local APIC > and all works fine. > > Can someone please tell me the reason, why local APIC doesnt work for the > Pentium 3 machines ? Or is there a way to fix this ? We don't detect the local APIC via MSR's or the APIC bit in cpu_features, but rely on a working MP Table or MADT table to setup both the local APIC(s) and I/O APIC(s). Does your machine have a valid MP Table or an APIC table in its acpidump? Many UP machine BIOSes don't include those tables. -- John Baldwin <jhb_at_FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.orgReceived on Sun Nov 06 2005 - 14:40:33 UTC
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