Hi Mark, On Fri, Oct 3, 2014 at 4:35 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: > On Thu, Sep 25, 2014 at 10:03:57AM +0100, Ganapatrao Kulkarni wrote: >> Adding Documentation for dt binding for memory to numa node mapping. > > As I previously commented [1], this binding doesn't specify what a nid > maps to in terms of the CPU hierarchy, and is thus unusable. The binding > absolutely must be explicit about this, and NAK until it is. The nid/numa node id is to map the each memory range/bank to numa node. IIUC, the numa manages the resources based on which node they are tide to. with nid, i am trying to map the memory range to a node. Same follows for the all IO peripherals and for CPUs. for cpus, i am using cluster-id as a node id to map all cpus to node. thunder has 2 nodes, in this patch, i have grouped all cpus which belongs to each node under cluster-id(cluster0, cluster1). > > Given we're seeing systems with increasing numbers of CPUs and > increasingly complex interconnect hierarchies, I would expect at minimum > that we would refer to elements in the cpu-map to define the > relationship between memory banks and CPUs. > > What does the interconnect/memory hierarchy look like in your system? In tunder, 2 SoCs (each has 48 cores and ram controllers and IOs) can be connected to form 2 node NUMA system. in a SoC(within node) there is no hierarchy with respect to memory or IO access. However w.r.t GICv3, 48 cores are in each SoC/node are split in to 3 clusters each of 16 cores. the MPIDR mapping for this topology is, Aff0 is mapped to 16 cores within a cluster. Valid range is 0 to 0xf Aff1 is mapped to cluster number, valid values are 0,1 and 2. Aff2 is mapped to Socket-id/node id/SoC number. Valid values are 0 and 1. > > Mark. > > [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-September/288263.html > >> >> Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxxxxxxxxxx> >> --- >> Documentation/devicetree/bindings/arm/numa.txt | 60 ++++++++++++++++++++++++++ >> 1 file changed, 60 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..1cdc6d3 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/numa.txt >> @@ -0,0 +1,60 @@ >> +======================================================== >> +ARM numa id binding description >> +======================================================== >> + >> +======================================================== >> +1 - Introduction >> +======================================================== >> + >> +The device node property nid (numa node id) can be added >> +to memory device node to map the range of memory addresses >> +as defined in property reg. The property nid maps the memory >> +range to the numa node id, which is used to find the local >> +and remote pages on numa aware systems. >> + >> +======================================================== >> +2 - nid property >> +======================================================== >> +nid is required property of memory device node for >> +numa enabled platforms. >> + >> +|------------------------------------------------------| >> +|Property Type | Usage | Value Type | Definition | >> +|------------------------------------------------------| >> +| nid | R | <u32> | Numa Node id | >> +| | | | for this memory | >> +|------------------------------------------------------| >> + >> +======================================================== >> +4 - Example memory nodes with numa information >> +======================================================== >> + >> +Example 1 (2 memory nodes, each mapped to a numa node.): >> + >> + memory@00000000 { >> + device_type = "memory"; >> + reg = <0x0 0x00000000 0x0 0x80000000>; >> + nid = <0x0>; >> + }; >> + >> + memory@10000000000 { >> + device_type = "memory"; >> + reg = <0x100 0x00000000 0x0 0x80000000>; >> + nid = <0x1>; >> + }; >> + >> +Example 2 (multiple memory ranges in each memory node and mapped to numa node): >> + >> + memory@00000000 { >> + device_type = "memory"; >> + reg = <0x0 0x00000000 0x0 0x80000000>, >> + <0x1 0x00000000 0x0 0x80000000>; >> + nid = <0x0>; >> + }; >> + >> + memory@10000000000 { >> + device_type = "memory"; >> + reg = <0x100 0x00000000 0x0 0x80000000>; >> + reg = <0x100 0x80000000 0x0 0x80000000>; >> + nid = <0x1>; >> + }; >> -- >> 1.8.1.4 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> thanks ganapat -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
