tegrakernel/kernel/kernel-4.9/Documentation/devicetree/bindings/interrupt-controller/img,pdc-intc.txt

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* ImgTec Powerdown Controller (PDC) Interrupt Controller Binding
This binding specifies what properties must be available in the device tree
representation of a PDC IRQ controller. This has a number of input interrupt
lines which can wake the system, and are passed on through output interrupt
lines.
Required properties:
- compatible: Specifies the compatibility list for the interrupt controller.
The type shall be <string> and the value shall include "img,pdc-intc".
- reg: Specifies the base PDC physical address(s) and size(s) of the
addressable register space. The type shall be <prop-encoded-array>.
- interrupt-controller: The presence of this property identifies the node
as an interrupt controller. No property value shall be defined.
- #interrupt-cells: Specifies the number of cells needed to encode an
interrupt source. The type shall be a <u32> and the value shall be 2.
- num-perips: Number of waking peripherals.
- num-syswakes: Number of SysWake inputs.
- interrupts: List of interrupt specifiers. The first specifier shall be the
shared SysWake interrupt, and remaining specifies shall be PDC peripheral
interrupts in order.
* Interrupt Specifier Definition
Interrupt specifiers consists of 2 cells encoded as follows:
- <1st-cell>: The interrupt-number that identifies the interrupt source.
0-7: Peripheral interrupts
8-15: SysWake interrupts
- <2nd-cell>: The level-sense information, encoded using the Linux interrupt
flags as follows (only 4 valid for peripheral interrupts):
0 = none (decided by software)
1 = low-to-high edge triggered
2 = high-to-low edge triggered
3 = both edge triggered
4 = active-high level-sensitive (required for perip irqs)
8 = active-low level-sensitive
* Examples
Example 1:
/*
* TZ1090 PDC block
*/
pdc: pdc@0x02006000 {
// This is an interrupt controller node.
interrupt-controller;
// Three cells to encode interrupt sources.
#interrupt-cells = <2>;
// Offset address of 0x02006000 and size of 0x1000.
reg = <0x02006000 0x1000>;
// Compatible with Meta hardware trigger block.
compatible = "img,pdc-intc";
// Three peripherals are connected.
num-perips = <3>;
// Four SysWakes are connected.
num-syswakes = <4>;
interrupts = <18 4 /* level */>, /* Syswakes */
<30 4 /* level */>, /* Peripheral 0 (RTC) */
<29 4 /* level */>, /* Peripheral 1 (IR) */
<31 4 /* level */>; /* Peripheral 2 (WDT) */
};
Example 2:
/*
* An SoC peripheral that is wired through the PDC.
*/
rtc0 {
// The interrupt controller that this device is wired to.
interrupt-parent = <&pdc>;
// Interrupt source Peripheral 0
interrupts = <0 /* Peripheral 0 (RTC) */
4> /* IRQ_TYPE_LEVEL_HIGH */
};
Example 3:
/*
* An interrupt generating device that is wired to a SysWake pin.
*/
touchscreen0 {
// The interrupt controller that this device is wired to.
interrupt-parent = <&pdc>;
// Interrupt source SysWake 0 that is active-low level-sensitive
interrupts = <8 /* SysWake0 */
8 /* IRQ_TYPE_LEVEL_LOW */>;
};