the UART FIFO.
The emulation is constrained in a number of ways: 64-bit only, doesn't check
for all exception conditions, limited to i/o ports emulated in userspace.
Some of these constraints will be relaxed in followup commits.
Requested by: grehan
Reviewed by: tychon (partially and a much earlier version)
commit level triggered interrupts would work as long as the pin was not shared
among multiple interrupt sources.
The vlapic now keeps track of level triggered interrupts in the trigger mode
register and will forward the EOI for a level triggered interrupt to the
vioapic. The vioapic in turn uses the EOI to sample the level on the pin and
re-inject the vector if the pin is still asserted.
The vhpet is the first consumer of level triggered interrupts and advertises
that it can generate interrupts on pins 20 through 23 of the vioapic.
Discussed with: grehan@
vmm.ko - kernel module for VT-x, VT-d and hypervisor control
bhyve - user-space sequencer and i/o emulation
vmmctl - dump of hypervisor register state
libvmm - front-end to vmm.ko chardev interface
bhyve was designed and implemented by Neel Natu.
Thanks to the following folk from NetApp who helped to make this available:
Joe CaraDonna
Peter Snyder
Jeff Heller
Sandeep Mann
Steve Miller
Brian Pawlowski
