dt-bindings: Add device-tree bindings for the ION memory manager

%YAML 1.2

---

$id: "http://devicetree.org/schemas/arm/msm/msm_ion.yaml#"

$schema: "http://devicetree.org/meta-schemas/core.yaml#"

title: ION Memory Manager binding

maintainers:

  - Isaac J. Manjarres <isaacm@quicinc.com>

description: |

  ION is a memory manager that allows for sharing of buffers between different

  processes and between user space and kernel space. ION manages different

  memory spaces by separating the memory spaces into heaps.

  All child nodes of a qcom,msm-ion node are interpreted as ION heap

  configurations.

properties:

  $nodename:

    const: qcom,ion

    description: Container of ION heap nodes

  compatible:

    items:

      -const: qcom,msm-ion

  '#address-cells':

    const: 1

  '#size-cells':

    const: 0

patternProperties:

  '^qcom,ion-heap@[0-9]+$':

    properties:

      reg:

        maxItems: 1

        description: The ID assigned to this heap.

      memory-region:

        $ref: '/schemas/types.yaml#/definitions/phandle'

        maxItems: 1

        description: |

          Specifies the reserved memory region that this heap will allocate

          memory from. This property is only required for heaps that draw memory

          from a particular reserved memory region. Refer to

          Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt

          for more information.

      qcom,ion-heap-type:

        $ref: '/schemas/types.yaml#/definitions/string'

        maxItems: 1

        items:

          - enum:

              - SYSTEM

              - CARVEOUT

              - SECURE_CARVEOUT

              - DMA

              - HYP_CMA

              - SYSTEM_SECURE

              - SECURE_DMA

        description: |

          The heap type to use for this heap. Heaps of type SECURE_CARVEOUT

          are expected to contain multiple child nodes, as seen below.

      $nodename:

        properties:

          memory-region:

            $ref: '/schemas/types.yaml#/definitions/phandle'

            maxItems: 1

            description: |

              Specifies the reserved memory region that this heap will allocate

              memory from. Refer to the reserved-memory binding documentation

              for more information.

          token:

            $ref: '/schemas/types.yaml#/definitions/uint32'

            minItems: 1

            description: |

              Specifies the set of secure domains which will be able to access

              the memory-region.

        required:

          - memory-region

          - token

    required:

      - reg

      - qcom,ion-heap-type

required:

  - compatible

  - '#address-cells'

  - '#size-cells'

examples:

  - |

    qcom,ion {

        compatible = "qcom,msm-ion";

        #address-cells = <1>;

        #size-cells = <0>;

        system_heap: qcom,ion-heap@25 {

            reg = <25>;

            qcom,ion-heap-type = "SYSTEM";

        };

        qcom,ion-heap@22 { /* ADSP HEAP */

            reg = <22>;

            memory-region = <&adsp_mem>;

            qcom,ion-heap-type = "DMA";

        };

        qcom,ion-heap@10 { /* SECURE DISPLAY HEAP */

            reg = <10>;

            memory-region = <&secure_display_memory>;

            qcom,ion-heap-type = "HYP_CMA";

        };

        qcom,ion-heap@9 {

            reg = <9>;

            qcom,ion-heap-type = "SYSTEM_SECURE";

        };

        qcom,ion-heap@14 {

            reg = <14>;

            qcom,ion-heap-type = "SECURE_CARVEOUT";

            node1 {

                memory-region = <&cp_region>;

                token = <ION_FLAG_CP_TOUCH>;

            };

        };

    };