Sorry, Mea Culpa, I should have written APIC timer.1. HW is LRR capable, HPET ACPI it is 1, timer interrupt is on INT2.
Before the fix: Linux cannot get timer interrupts on INT0, goes for ACPI timer.
What ACPI timer? I don't think we have any fallback for int 0.
Yes. PIN2 on IOAPIC #0.
Not sure what you mean with INT2. Pin2 on ioapic 0 perhaps?
SunFire X4600
After the fix : Works fine. This is according to hpet spec.
On what exact motherboard was that?
I feel I do not make things clear enough.
To handle case 3, I removed all references to acpi_hpet_lrr, explained
this case in the code and decided to solely rely on the command line
parameter for LRR capability. Rational for this approach is ,
This means the systems which you said fixes this would need the command
line parameter to work?