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+=======================================================
+ARM CCI cache coherent interconnect binding description
+=======================================================
+
+ARM multi-cluster systems maintain intra-cluster coherency through a
+cache coherent interconnect (CCI) that is capable of monitoring bus
+transactions and manage coherency, TLB invalidations and memory barriers.
+
+It allows snooping and distributed virtual memory message broadcast across
+clusters, through memory mapped interface, with a global control register
+space and multiple sets of interface control registers, one per slave
+interface.
+
+Bindings for the CCI node follow the ePAPR standard, available from:
+
+www.power.org/documentation/epapr-version-1-1/
+
+with the addition of the bindings described in this document which are
+specific to ARM.
+
+* CCI interconnect node
+
+ Description: Describes a CCI cache coherent Interconnect component
+
+ Node name must be "cci".
+ Node's parent must be the root node /, and the address space visible
+ through the CCI interconnect is the same as the one seen from the
+ root node (ie from CPUs perspective as per DT standard).
+ Every CCI node has to define the following properties:
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be set to
+ "arm,cci-400"
+
+ - reg
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: A standard property. Specifies base physical
+ address of CCI control registers common to all
+ interfaces.
+
+ - ranges:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: A standard property. Follow rules in the ePAPR for
+ hierarchical bus addressing. CCI interfaces
+ addresses refer to the parent node addressing
+ scheme to declare their register bases.
+
+ CCI interconnect node can define the following child nodes:
+
+ - CCI control interface nodes
+
+ Node name must be "slave-if".
+ Parent node must be CCI interconnect node.
+
+ A CCI control interface node must contain the following
+ properties:
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be set to
+ "arm,cci-400-ctrl-if"
+
+ - interface-type:
+ Usage: required
+ Value type: <string>
+ Definition: must be set to one of {"ace", "ace-lite"}
+ depending on the interface type the node
+ represents.
+
+ - reg:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: the base address and size of the
+ corresponding interface programming
+ registers.
+
+* CCI interconnect bus masters
+
+ Description: masters in the device tree connected to a CCI port
+ (inclusive of CPUs and their cpu nodes).
+
+ A CCI interconnect bus master node must contain the following
+ properties:
+
+ - cci-control-port:
+ Usage: required
+ Value type: <phandle>
+ Definition: a phandle containing the CCI control interface node
+ the master is connected to.
+
+Example:
+
+ cpus {
+ #size-cells = <0>;
+ #address-cells = <1>;
+
+ CPU0: cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ cci-control-port = <&cci_control1>;
+ reg = <0x0>;
+ };
+
+ CPU1: cpu@1 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a15";
+ cci-control-port = <&cci_control1>;
+ reg = <0x1>;
+ };
+
+ CPU2: cpu@100 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ cci-control-port = <&cci_control2>;
+ reg = <0x100>;
+ };
+
+ CPU3: cpu@101 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a7";
+ cci-control-port = <&cci_control2>;
+ reg = <0x101>;
+ };
+
+ };
+
+ dma0: dma@3000000 {
+ compatible = "arm,pl330", "arm,primecell";
+ cci-control-port = <&cci_control0>;
+ reg = <0x0 0x3000000 0x0 0x1000>;
+ interrupts = <10>;
+ #dma-cells = <1>;
+ #dma-channels = <8>;
+ #dma-requests = <32>;
+ };
+
+ cci@2c090000 {
+ compatible = "arm,cci-400";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = <0x0 0x2c090000 0 0x1000>;
+ ranges = <0x0 0x0 0x2c090000 0x6000>;
+
+ cci_control0: slave-if@1000 {
+ compatible = "arm,cci-400-ctrl-if";
+ interface-type = "ace-lite";
+ reg = <0x1000 0x1000>;
+ };
+
+ cci_control1: slave-if@4000 {
+ compatible = "arm,cci-400-ctrl-if";
+ interface-type = "ace";
+ reg = <0x4000 0x1000>;
+ };
+
+ cci_control2: slave-if@5000 {
+ compatible = "arm,cci-400-ctrl-if";
+ interface-type = "ace";
+ reg = <0x5000 0x1000>;
+ };
+ };
+
+This CCI node corresponds to a CCI component whose control registers sits
+at address 0x000000002c090000.
+CCI slave interface @0x000000002c091000 is connected to dma controller dma0.
+CCI slave interface @0x000000002c094000 is connected to CPUs {CPU0, CPU1};
+CCI slave interface @0x000000002c095000 is connected to CPUs {CPU2, CPU3};