interrupt_controller: change IO APIC to logical destination mode
Currently IO APIC is working in physical destination mode, which
doesn't support interrupt to be delivered to multiple local APICs.
By definition only 4 bits [59:63] in IO APIC IOREDTBL register are
available for destination addresses and it contains an APIC ID only.
This patch changes it to logical destination mode so that IOREDTBL
can potentially define a set of processors and it's posible to deliver
interrupts to multiple APICs.
Also it changes delivery mode from fixed to lowest priority. The reason
being in fixed mode, the interrupt could be delivered to all CPUs
which put burden in software to handle repeated interrupts. While in
lowest priority mode, interrupt is delivered to one local APIC only.
Signed-off-by:
Zide Chen <zide.chen@intel.com>
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