Messages in this thread | | | Date | Fri, 20 Oct 2017 10:22:10 +0100 | From | Lorenzo Pieralisi <> | Subject | Re: [PATCH v3 6/7] arm64: topology: Enable ACPI/PPTT based CPU topology. |
| |
On Thu, Oct 19, 2017 at 11:54:22AM -0500, Jeremy Linton wrote:
[...]
> >>+ cpu_topology[cpu].core_id = topology_id; > >>+ topology_id = setup_acpi_cpu_topology(cpu, 2); > >>+ cpu_topology[cpu].cluster_id = topology_id; > >>+ topology_id = setup_acpi_cpu_topology(cpu, max_topo); > > > >If you want a package id (that's just a package tag to group cores), you > >should not use a large level because you know how setup_acpi_cpu_topology()works, you should add an API that allows you to retrieve the package id > >(so that you can use th ACPI_PPTT_PHYSICAL_PACKAGE flag consistenly, > >whatever it represents). > > I don't think the spec requires the use of PHYSICAL_PACKAGE... Am I > misreading it? Which means we need to "pick" a node level to > represent the physical package if one doesn't exist...
The specs define a means to detect if a given PPTT node corresponds to a package (I am refraining from stating again that to me that's not clean cut what a package is _architecturally_, I think you know my POV by now) and that's what you need to use to retrieve a packageid for a given cpu, if I understand the aim of the physical package flag.
Either that or that flag is completely useless.
Lorenzo
ACPI 6.2 - Table 5-151 (page 248) Physical package ----------------- Set to 1 if this node of the processor topology represents the boundary of a physical package, whether socketed or surface mounted. Set to 0 if this instance of the processor topology does not represent the boundary of a physical package.
| |