Documentation/devicetree/bindings/soc/qcom/qcom,smp2p.yaml

   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
   7 title: Qualcomm Shared Memory Point 2 Point
   8
   9 maintainers:
  10   - Andy Gross <agross@kernel.org>
  11   - Bjorn Andersson <bjorn.andersson@linaro.org>
  12   - Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
  13
  14 description:
  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
  21 properties:
  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     $ref: /schemas/types.yaml#/definitions/uint32-array
  57     items:
  58       maxItems: 2
  59     description:
  60       Two identifiers of the inbound and outbound smem items used for this edge.
  61
  62 patternProperties:
  63   "^master-kernel|slave-kernel|ipa-ap-to-modem|ipa-modem-to-ap$":
  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
 105 required:
 106   - compatible
 107   - interrupts
 108   - qcom,local-pid
 109   - qcom,remote-pid
 110   - qcom,smem
 111
 112 oneOf:
 113   - required:
 114       - mboxes
 115   - required:
 116       - qcom,ipc
 117
 118 additionalProperties: false
 119
 120 examples:
 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     };