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Diffstat (limited to 'kernel/Documentation/devicetree/bindings/open-pic.txt')
-rw-r--r-- | kernel/Documentation/devicetree/bindings/open-pic.txt | 98 |
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diff --git a/kernel/Documentation/devicetree/bindings/open-pic.txt b/kernel/Documentation/devicetree/bindings/open-pic.txt deleted file mode 100644 index 909a902df..000000000 --- a/kernel/Documentation/devicetree/bindings/open-pic.txt +++ /dev/null @@ -1,98 +0,0 @@ -* Open PIC Binding - -This binding specifies what properties must be available in the device tree -representation of an Open PIC compliant interrupt controller. This binding is -based on the binding defined for Open PIC in [1] and is a superset of that -binding. - -Required properties: - - NOTE: Many of these descriptions were paraphrased here from [1] to aid - readability. - - - compatible: Specifies the compatibility list for the PIC. The type - shall be <string> and the value shall include "open-pic". - - - reg: Specifies the base physical address(s) and size(s) of this - PIC's addressable register space. The type shall be <prop-encoded-array>. - - - interrupt-controller: The presence of this property identifies the node - as an Open PIC. 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. - - - #address-cells: Specifies the number of cells needed to encode an - address. The type shall be <u32> and the value shall be 0. As such, - 'interrupt-map' nodes do not have to specify a parent unit address. - -Optional properties: - - - pic-no-reset: The presence of this property indicates that the PIC - shall not be reset during runtime initialization. No property value shall - be defined. The presence of this property also mandates that any - initialization related to interrupt sources shall be limited to sources - explicitly referenced in the device tree. - -* Interrupt Specifier Definition - - Interrupt specifiers consists of 2 cells encoded as - follows: - - - <1st-cell>: The interrupt-number that identifies the interrupt source. - - - <2nd-cell>: The level-sense information, encoded as follows: - 0 = low-to-high edge triggered - 1 = active low level-sensitive - 2 = active high level-sensitive - 3 = high-to-low edge triggered - -* Examples - -Example 1: - - /* - * An Open PIC interrupt controller - */ - mpic: pic@40000 { - // This is an interrupt controller node. - interrupt-controller; - - // No address cells so that 'interrupt-map' nodes which reference - // this Open PIC node do not need a parent address specifier. - #address-cells = <0>; - - // Two cells to encode interrupt sources. - #interrupt-cells = <2>; - - // Offset address of 0x40000 and size of 0x40000. - reg = <0x40000 0x40000>; - - // Compatible with Open PIC. - compatible = "open-pic"; - - // The PIC shall not be reset. - pic-no-reset; - }; - -Example 2: - - /* - * An interrupt generating device that is wired to an Open PIC. - */ - serial0: serial@4500 { - // Interrupt source '42' that is active high level-sensitive. - // Note that there are only two cells as specified in the interrupt - // parent's '#interrupt-cells' property. - interrupts = <42 2>; - - // The interrupt controller that this device is wired to. - interrupt-parent = <&mpic>; - }; - -* References - -[1] Power.org (TM) Standard for Embedded Power Architecture (TM) Platform - Requirements (ePAPR), Version 1.0, July 2008. - (http://www.power.org/resources/downloads/Power_ePAPR_APPROVED_v1.0.pdf) - |