DT bindings for numa map for memory, cores to node and proximity distance matrix of nodes to each other.
Signed-off-by: Ganapatrao Kulkarni <[email protected]> --- Documentation/devicetree/bindings/arm/numa.txt | 103 +++++++++++++++++++++++++ 1 file changed, 103 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/numa.txt diff --git a/Documentation/devicetree/bindings/arm/numa.txt b/Documentation/devicetree/bindings/arm/numa.txt new file mode 100644 index 0000000..ec6bf2d --- /dev/null +++ b/Documentation/devicetree/bindings/arm/numa.txt @@ -0,0 +1,103 @@ +============================================================================== +NUMA binding description. +============================================================================== + +============================================================================== +1 - Introduction +============================================================================== + +Systems employing a Non Uniform Memory Access (NUMA) architecture contain +collections of hardware resources including processors, memory, and I/O buses, +that comprise what is commonly known as a ???NUMA node???. Processor +accesses to memory within the local NUMA node is +generally faster than processor accesses to memory outside of the local +NUMA node. DT defines interfaces that allow the platform to convey NUMA node +topology information to OS. + +============================================================================== +2 - numa-map node +============================================================================== + +DT Binding for NUMA can be defined for memory and CPUs to map them to +respective NUMA nodes. + +The DT binding can defined using numa-map node. +The numa-map will have following properties to define NUMA topology. + +- mem-map: This property defines the association between a range of + memory and the proximity domain/numa node to which it belongs. + +note: memory range address is passed using either memory node of +DT or UEFI system table and should match to the address defined in mem-map. + +- cpu-map: This property defines the association of range of processors + (range of cpu ids) and the proximity domain to which + the processor belongs. + +- node-matrix: This table provides a matrix that describes the relative + distance (memory latency) between all System Localities. + The value of each Entry[i j distance] in node-matrix table, + where i represents a row of a matrix and j represents a + column of a matrix, indicates the relative distances + from Proximity Domain/Numa node i to every other + node j in the system (including itself). + +The numa-map node must contain the appropriate #address-cells, +#size-cells and #node-count properties. + + +============================================================================== +4 - Example dts +============================================================================== + +Example 1: 2 Node system each having 8 CPUs and a Memory. + + numa-map { + #address-cells = <2>; + #size-cells = <1>; + #node-count = <2>; + mem-map = <0x0 0x00000000 0>, + <0x100 0x00000000 1>; + + cpu-map = <0 7 0>, + <8 15 1>; + + node-matrix = <0 0 10>, + <0 1 20>, + <1 0 20>, + <1 1 10>; + }; + +Example 2: 4 Node system each having 4 CPUs and a Memory. + + numa-map { + #address-cells = <2>; + #size-cells = <1>; + #node-count = <2>; + mem-map = <0x0 0x00000000 0>, + <0x100 0x00000000 1>, + <0x200 0x00000000 2>, + <0x300 0x00000000 3>; + + cpu-map = <0 7 0>, + <8 15 1>, + <16 23 2>, + <24 31 3>; + + node-matrix = <0 0 10>, + <0 1 20>, + <0 2 20>, + <0 3 20>, + <1 0 20>, + <1 1 10>, + <1 2 20>, + <1 3 20>, + <2 0 20>, + <2 1 20>, + <2 2 10>, + <2 3 20>, + <3 0 20>, + <3 1 20>, + <3 2 20>, + <3 3 10>; + }; -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
