| ===================================================================== |
| Freescale MPIC Interrupt Controller Node |
| Copyright (C) 2010,2011 Freescale Semiconductor Inc. |
| ===================================================================== |
| |
| The Freescale MPIC interrupt controller is found on all PowerQUICC |
| and QorIQ processors and is compatible with the Open PIC. The |
| notable difference from Open PIC binding is the addition of 2 |
| additional cells in the interrupt specifier defining interrupt type |
| information. |
| |
| PROPERTIES |
| |
| - compatible |
| Usage: required |
| Value type: <string> |
| Definition: Shall include "fsl,mpic". Freescale MPIC |
| controllers compatible with this binding have Block |
| Revision Registers BRR1 and BRR2 at offset 0x0 and |
| 0x10 in the MPIC. |
| |
| - reg |
| Usage: required |
| Value type: <prop-encoded-array> |
| Definition: A standard property. Specifies the physical |
| offset and length of the device's registers within the |
| CCSR address space. |
| |
| - interrupt-controller |
| Usage: required |
| Value type: <empty> |
| Definition: Specifies that this node is an interrupt |
| controller |
| |
| - #interrupt-cells |
| Usage: required |
| Value type: <u32> |
| Definition: Shall be 2 or 4. A value of 2 means that interrupt |
| specifiers do not contain the interrupt-type or type-specific |
| information cells. |
| |
| - #address-cells |
| Usage: required |
| Value type: <u32> |
| Definition: Shall be 0. |
| |
| - pic-no-reset |
| Usage: optional |
| Value type: <empty> |
| Definition: The presence of this property specifies that the |
| MPIC must not be reset by the client program, and that |
| the boot program has initialized all interrupt source |
| configuration registers to a sane state-- masked or |
| directed at other cores. This ensures that the client |
| program will not receive interrupts for sources not belonging |
| to the client. 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. |
| |
| - big-endian |
| Usage: optional |
| Value type: <empty> |
| If present the MPIC will be assumed to be big-endian. Some |
| device-trees omit this property on MPIC nodes even when the MPIC is |
| in fact big-endian, so certain boards override this property. |
| |
| - single-cpu-affinity |
| Usage: optional |
| Value type: <empty> |
| If present the MPIC will be assumed to only be able to route |
| non-IPI interrupts to a single CPU at a time (EG: Freescale MPIC). |
| |
| - last-interrupt-source |
| Usage: optional |
| Value type: <u32> |
| Some MPICs do not correctly report the number of hardware sources |
| in the global feature registers. If specified, this field will |
| override the value read from MPIC_GREG_FEATURE_LAST_SRC. |
| |
| INTERRUPT SPECIFIER DEFINITION |
| |
| Interrupt specifiers consists of 4 cells encoded as |
| follows: |
| |
| <1st-cell> interrupt-number |
| |
| Identifies the interrupt source. The meaning |
| depends on the type of interrupt. |
| |
| Note: If the interrupt-type cell is undefined |
| (i.e. #interrupt-cells = 2), this cell |
| should be interpreted the same as for |
| interrupt-type 0-- i.e. an external or |
| normal SoC device interrupt. |
| |
| <2nd-cell> 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 |
| |
| <3rd-cell> interrupt-type |
| |
| The following types are supported: |
| |
| 0 = external or normal SoC device interrupt |
| |
| The interrupt-number cell contains |
| the SoC device interrupt number. The |
| type-specific cell is undefined. The |
| interrupt-number is derived from the |
| MPIC a block of registers referred to as |
| the "Interrupt Source Configuration Registers". |
| Each source has 32-bytes of registers |
| (vector/priority and destination) in this |
| region. So interrupt 0 is at offset 0x0, |
| interrupt 1 is at offset 0x20, and so on. |
| |
| 1 = error interrupt |
| |
| The interrupt-number cell contains |
| the SoC device interrupt number for |
| the error interrupt. The type-specific |
| cell identifies the specific error |
| interrupt number. |
| |
| 2 = MPIC inter-processor interrupt (IPI) |
| |
| The interrupt-number cell identifies |
| the MPIC IPI number. The type-specific |
| cell is undefined. |
| |
| 3 = MPIC timer interrupt |
| |
| The interrupt-number cell identifies |
| the MPIC timer number. The type-specific |
| cell is undefined. |
| |
| <4th-cell> type-specific information |
| |
| The type-specific cell is encoded as follows: |
| |
| - For interrupt-type 1 (error interrupt), |
| the type-specific cell contains the |
| bit number of the error interrupt in the |
| Error Interrupt Summary Register. |
| |
| EXAMPLE 1 |
| /* |
| * mpic interrupt controller with 4 cells per specifier |
| */ |
| mpic: pic@40000 { |
| compatible = "fsl,mpic"; |
| interrupt-controller; |
| #interrupt-cells = <4>; |
| #address-cells = <0>; |
| reg = <0x40000 0x40000>; |
| }; |
| |
| EXAMPLE 2 |
| /* |
| * The MPC8544 I2C controller node has an internal |
| * interrupt number of 27. As per the reference manual |
| * this corresponds to interrupt source configuration |
| * registers at 0x5_0560. |
| * |
| * The interrupt source configuration registers begin |
| * at 0x5_0000. |
| * |
| * To compute the interrupt specifier interrupt number |
| * |
| * 0x560 >> 5 = 43 |
| * |
| * The interrupt source configuration registers begin |
| * at 0x5_0000, and so the i2c vector/priority registers |
| * are at 0x5_0560. |
| */ |
| i2c@3000 { |
| #address-cells = <1>; |
| #size-cells = <0>; |
| cell-index = <0>; |
| compatible = "fsl-i2c"; |
| reg = <0x3000 0x100>; |
| interrupts = <43 2>; |
| interrupt-parent = <&mpic>; |
| dfsrr; |
| }; |
| |
| |
| EXAMPLE 3 |
| /* |
| * Definition of a node defining the 4 |
| * MPIC IPI interrupts. Note the interrupt |
| * type of 2. |
| */ |
| ipi@410a0 { |
| compatible = "fsl,mpic-ipi"; |
| reg = <0x40040 0x10>; |
| interrupts = <0 0 2 0 |
| 1 0 2 0 |
| 2 0 2 0 |
| 3 0 2 0>; |
| }; |
| |
| EXAMPLE 4 |
| /* |
| * Definition of a node defining the MPIC |
| * global timers. Note the interrupt |
| * type of 3. |
| */ |
| timer0: timer@41100 { |
| compatible = "fsl,mpic-global-timer"; |
| reg = <0x41100 0x100 0x41300 4>; |
| interrupts = <0 0 3 0 |
| 1 0 3 0 |
| 2 0 3 0 |
| 3 0 3 0>; |
| }; |
| |
| EXAMPLE 5 |
| /* |
| * Definition of an error interrupt (interrupt type 1). |
| * SoC interrupt number is 16 and the specific error |
| * interrupt bit in the error interrupt summary register |
| * is 23. |
| */ |
| memory-controller@8000 { |
| compatible = "fsl,p4080-memory-controller"; |
| reg = <0x8000 0x1000>; |
| interrupts = <16 2 1 23>; |
| }; |
