1 =====================================================================
2 Freescale MPIC Interrupt Controller Node
3 Copyright (C) 2010,2011 Freescale Semiconductor Inc.
4 =====================================================================
5
6 The Freescale MPIC interrupt controller is found on all PowerQUICC
7 and QorIQ processors and is compatible with the Open PIC. The
8 notable difference from Open PIC binding is the addition of 2
9 additional cells in the interrupt specifier defining interrupt type
10 information.
11
12 PROPERTIES
13
14 - compatible
15 Usage: required
16 Value type: <string>
17 Definition: Shall include "fsl,mpic". Freescale MPIC
18 controllers compatible with this binding have Block
19 Revision Registers BRR1 and BRR2 at offset 0x0 and
20 0x10 in the MPIC.
21
22 - reg
23 Usage: required
24 Value type: <prop-encoded-array>
25 Definition: A standard property. Specifies the physical
26 offset and length of the device's registers within the
27 CCSR address space.
28
29 - interrupt-controller
30 Usage: required
31 Value type: <empty>
32 Definition: Specifies that this node is an interrupt
33 controller
34
35 - #interrupt-cells
36 Usage: required
37 Value type: <u32>
38 Definition: Shall be 2 or 4. A value of 2 means that interrupt
39 specifiers do not contain the interrupt-type or type-specific
40 information cells.
41
42 - #address-cells
43 Usage: required
44 Value type: <u32>
45 Definition: Shall be 0.
46
47 - pic-no-reset
48 Usage: optional
49 Value type: <empty>
50 Definition: The presence of this property specifies that the
51 MPIC must not be reset by the client program, and that
52 the boot program has initialized all interrupt source
53 configuration registers to a sane state-- masked or
54 directed at other cores. This ensures that the client
55 program will not receive interrupts for sources not belonging
56 to the client. The presence of this property also mandates
57 that any initialization related to interrupt sources shall
58 be limited to sources explicitly referenced in the device tree.
59
60 - big-endian
61 Usage: optional
62 Value type: <empty>
63 If present the MPIC will be assumed to be big-endian. Some
64 device-trees omit this property on MPIC nodes even when the MPIC is
65 in fact big-endian, so certain boards override this property.
66
67 - single-cpu-affinity
68 Usage: optional
69 Value type: <empty>
70 If present the MPIC will be assumed to only be able to route
71 non-IPI interrupts to a single CPU at a time (EG: Freescale MPIC).
72
73 - last-interrupt-source
74 Usage: optional
75 Value type: <u32>
76 Some MPICs do not correctly report the number of hardware sources
77 in the global feature registers. If specified, this field will
78 override the value read from MPIC_GREG_FEATURE_LAST_SRC.
79
80 INTERRUPT SPECIFIER DEFINITION
81
82 Interrupt specifiers consists of 4 cells encoded as
83 follows:
84
85 <1st-cell> interrupt-number
86
87 Identifies the interrupt source. The meaning
88 depends on the type of interrupt.
89
90 Note: If the interrupt-type cell is undefined
91 (i.e. #interrupt-cells = 2), this cell
92 should be interpreted the same as for
93 interrupt-type 0-- i.e. an external or
94 normal SoC device interrupt.
95
96 <2nd-cell> level-sense information, encoded as follows:
97 0 = low-to-high edge triggered
98 1 = active low level-sensitive
99 2 = active high level-sensitive
100 3 = high-to-low edge triggered
101
102 <3rd-cell> interrupt-type
103
104 The following types are supported:
105
106 0 = external or normal SoC device interrupt
107
108 The interrupt-number cell contains
109 the SoC device interrupt number. The
110 type-specific cell is undefined. The
111 interrupt-number is derived from the
112 MPIC a block of registers referred to as
113 the "Interrupt Source Configuration Registers".
114 Each source has 32-bytes of registers
115 (vector/priority and destination) in this
116 region. So interrupt 0 is at offset 0x0,
117 interrupt 1 is at offset 0x20, and so on.
118
119 1 = error interrupt
120
121 The interrupt-number cell contains
122 the SoC device interrupt number for
123 the error interrupt. The type-specific
124 cell identifies the specific error
125 interrupt number.
126
127 2 = MPIC inter-processor interrupt (IPI)
128
129 The interrupt-number cell identifies
130 the MPIC IPI number. The type-specific
131 cell is undefined.
132
133 3 = MPIC timer interrupt
134
135 The interrupt-number cell identifies
136 the MPIC timer number. The type-specific
137 cell is undefined.
138
139 <4th-cell> type-specific information
140
141 The type-specific cell is encoded as follows:
142
143 - For interrupt-type 1 (error interrupt),
144 the type-specific cell contains the
145 bit number of the error interrupt in the
146 Error Interrupt Summary Register.
147
148 EXAMPLE 1
149 /*
150 * mpic interrupt controller with 4 cells per specifier
151 */
152 mpic: pic@40000 {
153 compatible = "fsl,mpic";
154 interrupt-controller;
155 #interrupt-cells = <4>;
156 #address-cells = <0>;
157 reg = <0x40000 0x40000>;
158 };
159
160 EXAMPLE 2
161 /*
162 * The MPC8544 I2C controller node has an internal
163 * interrupt number of 27. As per the reference manual
164 * this corresponds to interrupt source configuration
165 * registers at 0x5_0560.
166 *
167 * The interrupt source configuration registers begin
168 * at 0x5_0000.
169 *
170 * To compute the interrupt specifier interrupt number
171 *
172 * 0x560 >> 5 = 43
173 *
174 * The interrupt source configuration registers begin
175 * at 0x5_0000, and so the i2c vector/priority registers
176 * are at 0x5_0560.
177 */
178 i2c@3000 {
179 #address-cells = <1>;
180 #size-cells = <0>;
181 cell-index = <0>;
182 compatible = "fsl-i2c";
183 reg = <0x3000 0x100>;
184 interrupts = <43 2>;
185 interrupt-parent = <&mpic>;
186 dfsrr;
187 };
188
189
190 EXAMPLE 3
191 /*
192 * Definition of a node defining the 4
193 * MPIC IPI interrupts. Note the interrupt
194 * type of 2.
195 */
196 ipi@410a0 {
197 compatible = "fsl,mpic-ipi";
198 reg = <0x40040 0x10>;
199 interrupts = <0 0 2 0
200 1 0 2 0
201 2 0 2 0
202 3 0 2 0>;
203 };
204
205 EXAMPLE 4
206 /*
207 * Definition of a node defining the MPIC
208 * global timers. Note the interrupt
209 * type of 3.
210 */
211 timer0: timer@41100 {
212 compatible = "fsl,mpic-global-timer";
213 reg = <0x41100 0x100 0x41300 4>;
214 interrupts = <0 0 3 0
215 1 0 3 0
216 2 0 3 0
217 3 0 3 0>;
218 };
219
220 EXAMPLE 5
221 /*
222 * Definition of an error interrupt (interrupt type 1).
223 * SoC interrupt number is 16 and the specific error
224 * interrupt bit in the error interrupt summary register
225 * is 23.
226 */
227 memory-controller@8000 {
228 compatible = "fsl,p4080-memory-controller";
229 reg = <0x8000 0x1000>;
230 interrupts = <16 2 1 23>;
231 };
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