msi - Message Signaled Interrupt
Messaged Signaled Interrupts are used in modern PCI as well as
some ARM GIC controllers. MSI objects allow a privileged userspace
process to allocate a range of MSIs and associated IRQ vectors for
use with device drivers to allocate interrupt objects.
The most common use for an MSI object is to allocate a range of MSIs
to provide to a PCI device's Message Signaled Interrupt Capability.
Subsequently, the platform or PCI bus driver may use this object to
allocate interrupt objects corresponding to those MSIs for use
in downstream device drivers.
zx_msi_allocate()- allocate a range of message-signaled interruptszx_msi_create()- create a message-signaled interrupt object