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diff --git a/Documentation/devicetree/bindings/arm/cci.txt b/Documentation/devicetree/bindings/arm/cci.txt new file mode 100644 index 000000000..9600761f2 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/cci.txt @@ -0,0 +1,224 @@ +======================================================= +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. + +* 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 contain one of the following: + "arm,cci-400" + "arm,cci-500" + "arm,cci-550" + + - reg + Usage: required + Value type: Integer cells. A register entry, expressed as a pair + of cells, containing base and size. + Definition: A standard property. Specifies base physical + address of CCI control registers common to all + interfaces. + + - ranges: + Usage: required + Value type: Integer cells. An array of range entries, expressed + as a tuple of cells, containing child address, + parent address and the size of the region in the + child address space. + Definition: A standard property. Follow rules in the Devicetree + Specification 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: Integer cells. A register entry, expressed + as a pair of cells, containing base and + size. + Definition: the base address and size of the + corresponding interface programming + registers. + + - CCI PMU node + + Parent node must be CCI interconnect node. + + A CCI pmu node must contain the following properties: + + - compatible + Usage: required + Value type: <string> + Definition: Must contain one of: + "arm,cci-400-pmu,r0" + "arm,cci-400-pmu,r1" + "arm,cci-400-pmu" - DEPRECATED, permitted only where OS has + secure access to CCI registers + "arm,cci-500-pmu,r0" + "arm,cci-550-pmu,r0" + - reg: + Usage: required + Value type: Integer cells. A register entry, expressed + as a pair of cells, containing base and + size. + Definition: the base address and size of the + corresponding interface programming + registers. + + - interrupts: + Usage: required + Value type: Integer cells. Array of interrupt specifier + entries, as defined in + ../interrupt-controller/interrupts.txt. + Definition: list of counter overflow interrupts, one per + counter. The interrupts must be specified + starting with the cycle counter overflow + interrupt, followed by counter0 overflow + interrupt, counter1 overflow interrupt,... + ,counterN overflow interrupt. + + The CCI PMU has an interrupt signal for each + counter. The number of interrupts must be + equal to the number of counters. + +* 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 0x10000>; + + 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>; + }; + + pmu@9000 { + compatible = "arm,cci-400-pmu"; + reg = <0x9000 0x5000>; + interrupts = <0 101 4>, + <0 102 4>, + <0 103 4>, + <0 104 4>, + <0 105 4>; + }; + }; + +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}; |