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1* Freescale Communications Processor Module2 3NOTE: This is an interim binding, and will likely change slightly,4as more devices are supported. The QE bindings especially are5incomplete.6 7* Root CPM node8 9Properties:10- compatible : "fsl,cpm1", "fsl,cpm2", or "fsl,qe".11- reg : A 48-byte region beginning with CPCR.12 13Example:14 cpm@119c0 {15 #address-cells = <1>;16 #size-cells = <1>;17 #interrupt-cells = <2>;18 compatible = "fsl,mpc8272-cpm", "fsl,cpm2";19 reg = <119c0 30>;20 }21 22* Properties common to multiple CPM/QE devices23 24- fsl,cpm-command : This value is ORed with the opcode and command flag25 to specify the device on which a CPM command operates.26 27- fsl,cpm-brg : Indicates which baud rate generator the device28 is associated with. If absent, an unused BRG29 should be dynamically allocated. If zero, the30 device uses an external clock rather than a BRG.31 32- reg : Unless otherwise specified, the first resource represents the33 scc/fcc/ucc registers, and the second represents the device's34 parameter RAM region (if it has one).35 36* Multi-User RAM (MURAM)37 38The multi-user/dual-ported RAM is expressed as a bus under the CPM node.39 40Ranges must be set up subject to the following restrictions:41 42- Children's reg nodes must be offsets from the start of all muram, even43 if the user-data area does not begin at zero.44- If multiple range entries are used, the difference between the parent45 address and the child address must be the same in all, so that a single46 mapping can cover them all while maintaining the ability to determine47 CPM-side offsets with pointer subtraction. It is recommended that48 multiple range entries not be used.49- A child address of zero must be translatable, even if no reg resources50 contain it.51 52A child "data" node must exist, compatible with "fsl,cpm-muram-data", to53indicate the portion of muram that is usable by the OS for arbitrary54purposes. The data node may have an arbitrary number of reg resources,55all of which contribute to the allocatable muram pool.56 57Example, based on mpc8272:58 muram@0 {59 #address-cells = <1>;60 #size-cells = <1>;61 ranges = <0 0 10000>;62 63 data@0 {64 compatible = "fsl,cpm-muram-data";65 reg = <0 2000 9800 800>;66 };67 };68