- Samsung Exynos Interrupt Combiner Controller
Samsung’s Exynos4 architecture includes a interrupt combiner controller which
can combine interrupt sources as a group and provide a single interrupt request
for the group. The interrupt request from each group are connected to a parent
interrupt controller, such as GIC in case of Exynos4210.
The interrupt combiner controller consists of multiple combiners. Up to eight
interrupt sources can be connected to a combiner. The combiner outputs one
combined interrupt for its eight interrupt sources. The combined interrupt
is usually connected to a parent interrupt controller.
A single node in the device tree is used to describe the interrupt combiner
controller module (which includes multiple combiners). A combiner in the
interrupt controller module shares config/control registers with other
combiners. For example, a 32-bit interrupt enable/disable config register
can accommodate up to 4 interrupt combiners (with each combiner supporting
up to 8 interrupt sources).
Required properties:
- compatible: should be “samsung,exynos4210-combiner”.
- interrupt-controller: Identifies the node as an interrupt controller.
- #interrupt-cells: should be <2>. The meaning of the cells are
- First Cell: Combiner Group Number.
- Second Cell: Interrupt number within the group.
- reg: Base address and size of interrupt combiner registers.
- interrupts: The list of interrupts generated by the combiners which are then
connected to a parent interrupt controller. The format of the interrupt
specifier depends in the interrupt parent controller.
Optional properties:
- samsung,combiner-nr: The number of interrupt combiners supported. If this
property is not specified, the default number of combiners is assumed
to be 16. - interrupt-parent: pHandle of the parent interrupt controller, if not
inherited from the parent node.
Example:
The following is a an example from the Exynos4210 SoC dtsi file.
combiner:interrupt-controller@10440000 {
compatible = "samsung,exynos4210-combiner";
interrupt-controller;
#interrupt-cells = <2>;
reg = <0x10440000 0x1000>;
interrupts = <0 0 0>, <0 1 0>, <0 2 0>, <0 3 0>,
<0 4 0>, <0 5 0>, <0 6 0>, <0 7 0>,
<0 8 0>, <0 9 0>, <0 10 0>, <0 11 0>,
<0 12 0>, <0 13 0>, <0 14 0>, <0 15 0>;
};