xref: /linux/Documentation/devicetree/bindings/soc/qcom/qcom,smp2p.yaml (revision f777316e52e14059a6a1df45cbf39a93ac49a593) 
1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/soc/qcom/qcom,smp2p.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Qualcomm Shared Memory Point 2 Point
8
9maintainers:
10  - Andy Gross <agross@kernel.org>
11  - Bjorn Andersson <bjorn.andersson@linaro.org>
12  - Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
13
14description:
15  The Shared Memory Point to Point (SMP2P) protocol facilitates communication
16  of a single 32-bit value between two processors.  Each value has a single
17  writer (the local side) and a single reader (the remote side).  Values are
18  uniquely identified in the system by the directed edge (local processor ID to
19  remote processor ID) and a string identifier.
20
21properties:
22  compatible:
23    const: qcom,smp2p
24
25  interrupts:
26    maxItems: 1
27
28  mboxes:
29    maxItems: 1
30    description:
31      Reference to the mailbox representing the outgoing doorbell in APCS for
32      this client.
33
34  qcom,ipc:
35    $ref: /schemas/types.yaml#/definitions/phandle-array
36    items:
37      - items:
38          - description: phandle to a syscon node representing the APCS registers
39          - description: u32 representing offset to the register within the syscon
40          - description: u32 representing the ipc bit within the register
41    description:
42      Three entries specifying the outgoing ipc bit used for signaling the
43      remote end of the smp2p edge.
44
45  qcom,local-pid:
46    $ref: /schemas/types.yaml#/definitions/uint32
47    description:
48      The identifier of the local endpoint of this edge.
49
50  qcom,remote-pid:
51    $ref: /schemas/types.yaml#/definitions/uint32
52    description:
53      The identifier of the remote endpoint of this edge.
54
55  qcom,smem:
56    $ref: /schemas/types.yaml#/definitions/uint32-array
57    items:
58      maxItems: 2
59    description:
60      Two identifiers of the inbound and outbound smem items used for this edge.
61
62patternProperties:
63  "^master-kernel|slave-kernel|ipa-ap-to-modem|ipa-modem-to-ap$":
64    type: object
65    description:
66      Each SMP2P pair contain a set of inbound and outbound entries, these are
67      described in subnodes of the smp2p device node. The node names are not
68      important.
69
70    properties:
71      interrupt-controller:
72        description:
73          Marks the entry as inbound; the node should be specified as a two
74          cell interrupt-controller.  If not specified this node will denote
75          the outgoing entry.
76
77      '#interrupt-cells':
78        const: 2
79
80      qcom,entry-name:
81        $ref: /schemas/types.yaml#/definitions/string
82        description:
83          The name of this entry, for inbound entries this will be used to
84          match against the remotely allocated entry and for outbound entries
85          this name is used for allocating entries.
86
87      '#qcom,smem-state-cells':
88        $ref: /schemas/types.yaml#/definitions/uint32
89        const: 1
90        description:
91          Required for outgoing entries.
92
93    required:
94      - qcom,entry-name
95
96    oneOf:
97      - required:
98          - interrupt-controller
99          - '#interrupt-cells'
100      - required:
101          - '#qcom,smem-state-cells'
102
103    additionalProperties: false
104
105required:
106  - compatible
107  - interrupts
108  - qcom,local-pid
109  - qcom,remote-pid
110  - qcom,smem
111
112oneOf:
113  - required:
114      - mboxes
115  - required:
116      - qcom,ipc
117
118additionalProperties: false
119
120examples:
121  # The following example shows the SMP2P setup with the wireless processor,
122  # defined from the 8974 apps processor's point-of-view. It encompasses one
123  # inbound and one outbound entry.
124  - |
125    #include <dt-bindings/interrupt-controller/arm-gic.h>
126
127    shared-memory {
128        compatible = "qcom,smp2p";
129        qcom,smem = <431>, <451>;
130        interrupts = <GIC_SPI 143 IRQ_TYPE_EDGE_RISING>;
131        qcom,ipc = <&apcs 8 18>;
132        qcom,local-pid = <0>;
133        qcom,remote-pid = <4>;
134
135        wcnss_smp2p_out: master-kernel {
136            qcom,entry-name = "master-kernel";
137            #qcom,smem-state-cells = <1>;
138        };
139
140        wcnss_smp2p_in: slave-kernel {
141            qcom,entry-name = "slave-kernel";
142            interrupt-controller;
143            #interrupt-cells = <2>;
144        };
145    };
146