u-boot/doc/device-tree-bindings/misc/intel,irq-router.txt

Intel Interrupt Router Device Binding
=====================================

The device tree node which describes the operation of the Intel Interrupt Router
device is as follows:

Required properties :
- reg : Specifies the interrupt router's PCI configuration space address as
    defined by the Open Firmware spec.
- compatible = "intel,irq-router"
- intel,pirq-config : Specifies the IRQ routing register programming mechanism.
    Valid values are:
      "pci": IRQ routing is controlled by PCI configuration registers
      "ibase": IRQ routing is in the memory-mapped IBASE register block
- intel,ibase-offset : IBASE register offset in the interrupt router's PCI
    configuration space, required only if intel,pirq-config = "ibase".
- intel,actl-8bit : If ACTL (ACPI control) register width is 8-bit, this must
    be specified. The 8-bit ACTL register is seen on ICH series chipset, like
    ICH9/Panther Point/etc. On Atom chipset it is a 32-bit register.
- intel,actl-addr : ACTL (ACPI control) register offset. ACTL can be either
    in the interrupt router's PCI configuration space, or IBASE.
- intel,pirq-link : Specifies the PIRQ link information with two cells. The
    first cell is the register offset that controls the first PIRQ link routing.
    The second cell is the total number of PIRQ links the router supports.
- intel,pirq-mask : Specifies the IRQ mask representing the 16 IRQs in the
    8259 PIC. Bit N is 1 means IRQ N is available to be routed.
- intel,pirq-routing : Specifies all PCI devices' IRQ routing information,
   encoded as 3 cells a group for a device. The first cell is the device's PCI
   bus number, device number and function number encoding with PCI_BDF() macro.
   The second cell is the PCI interrupt pin used by this device. The last cell
   is which PIRQ line the PCI interrupt pin is routed to.


Example
-------

#include <dt-bindings/interrupt-router/intel-irq.h>

	irq-router@1f,0 {
		reg = <0x0000f800 0 0 0 0>;
		compatible = "intel,irq-router";
		intel,pirq-config = "pci";
		intel,pirq-link = <0x60 8>;
		intel,pirq-mask = <0xdef8>;
		intel,pirq-routing = <
			PCI_BDF(0, 2, 0) INTA PIRQA
			PCI_BDF(0, 3, 0) INTA PIRQB
			PCI_BDF(0, 8, 0) INTA PIRQC
			PCI_BDF(0, 8, 1) INTB PIRQD
			PCI_BDF(1, 6, 0) INTA PIRQE
			PCI_BDF(1, 6, 1) INTB PIRQF
			PCI_BDF(1, 6, 2) INTC PIRQG
			PCI_BDF(1, 6, 3) INTD PIRQH
		>;
	};