James Hogan | b6ef916 | 2013-04-22 15:43:50 +0100 | [diff] [blame] | 1 | * ImgTec Powerdown Controller (PDC) Interrupt Controller Binding |
| 2 | |
| 3 | This binding specifies what properties must be available in the device tree |
| 4 | representation of a PDC IRQ controller. This has a number of input interrupt |
| 5 | lines which can wake the system, and are passed on through output interrupt |
| 6 | lines. |
| 7 | |
| 8 | Required properties: |
| 9 | |
| 10 | - compatible: Specifies the compatibility list for the interrupt controller. |
| 11 | The type shall be <string> and the value shall include "img,pdc-intc". |
| 12 | |
| 13 | - reg: Specifies the base PDC physical address(s) and size(s) of the |
| 14 | addressable register space. The type shall be <prop-encoded-array>. |
| 15 | |
| 16 | - interrupt-controller: The presence of this property identifies the node |
| 17 | as an interrupt controller. No property value shall be defined. |
| 18 | |
| 19 | - #interrupt-cells: Specifies the number of cells needed to encode an |
| 20 | interrupt source. The type shall be a <u32> and the value shall be 2. |
| 21 | |
| 22 | - num-perips: Number of waking peripherals. |
| 23 | |
| 24 | - num-syswakes: Number of SysWake inputs. |
| 25 | |
| 26 | - interrupts: List of interrupt specifiers. The first specifier shall be the |
| 27 | shared SysWake interrupt, and remaining specifies shall be PDC peripheral |
| 28 | interrupts in order. |
| 29 | |
| 30 | * Interrupt Specifier Definition |
| 31 | |
| 32 | Interrupt specifiers consists of 2 cells encoded as follows: |
| 33 | |
| 34 | - <1st-cell>: The interrupt-number that identifies the interrupt source. |
| 35 | 0-7: Peripheral interrupts |
| 36 | 8-15: SysWake interrupts |
| 37 | |
| 38 | - <2nd-cell>: The level-sense information, encoded using the Linux interrupt |
| 39 | flags as follows (only 4 valid for peripheral interrupts): |
| 40 | 0 = none (decided by software) |
| 41 | 1 = low-to-high edge triggered |
| 42 | 2 = high-to-low edge triggered |
| 43 | 3 = both edge triggered |
| 44 | 4 = active-high level-sensitive (required for perip irqs) |
| 45 | 8 = active-low level-sensitive |
| 46 | |
| 47 | * Examples |
| 48 | |
| 49 | Example 1: |
| 50 | |
| 51 | /* |
| 52 | * TZ1090 PDC block |
| 53 | */ |
| 54 | pdc: pdc@0x02006000 { |
| 55 | // This is an interrupt controller node. |
| 56 | interrupt-controller; |
| 57 | |
| 58 | // Three cells to encode interrupt sources. |
| 59 | #interrupt-cells = <2>; |
| 60 | |
| 61 | // Offset address of 0x02006000 and size of 0x1000. |
| 62 | reg = <0x02006000 0x1000>; |
| 63 | |
| 64 | // Compatible with Meta hardware trigger block. |
| 65 | compatible = "img,pdc-intc"; |
| 66 | |
| 67 | // Three peripherals are connected. |
| 68 | num-perips = <3>; |
| 69 | |
| 70 | // Four SysWakes are connected. |
| 71 | num-syswakes = <4>; |
| 72 | |
| 73 | interrupts = <18 4 /* level */>, /* Syswakes */ |
| 74 | <30 4 /* level */>, /* Peripheral 0 (RTC) */ |
| 75 | <29 4 /* level */>, /* Peripheral 1 (IR) */ |
| 76 | <31 4 /* level */>; /* Peripheral 2 (WDT) */ |
| 77 | }; |
| 78 | |
| 79 | Example 2: |
| 80 | |
| 81 | /* |
| 82 | * An SoC peripheral that is wired through the PDC. |
| 83 | */ |
| 84 | rtc0 { |
| 85 | // The interrupt controller that this device is wired to. |
| 86 | interrupt-parent = <&pdc>; |
| 87 | |
| 88 | // Interrupt source Peripheral 0 |
| 89 | interrupts = <0 /* Peripheral 0 (RTC) */ |
| 90 | 4> /* IRQ_TYPE_LEVEL_HIGH */ |
| 91 | }; |
| 92 | |
| 93 | Example 3: |
| 94 | |
| 95 | /* |
| 96 | * An interrupt generating device that is wired to a SysWake pin. |
| 97 | */ |
| 98 | touchscreen0 { |
| 99 | // The interrupt controller that this device is wired to. |
| 100 | interrupt-parent = <&pdc>; |
| 101 | |
| 102 | // Interrupt source SysWake 0 that is active-low level-sensitive |
| 103 | interrupts = <8 /* SysWake0 */ |
| 104 | 8 /* IRQ_TYPE_LEVEL_LOW */>; |
| 105 | }; |