Hi Mark, On Mon, May 21, 2018 at 4:25 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: > On Sat, May 05, 2018 at 12:16:13AM +0530, Ganapatrao Kulkarni wrote: >> On Thu, Apr 26, 2018 at 4:29 PM, Mark Rutland <mark.rutland@xxxxxxx> wrote: >> > On Wed, Apr 25, 2018 at 02:30:47PM +0530, Ganapatrao Kulkarni wrote: > >> >> + * >> >> + * L3 Tile and DMC channel selection is through SMC call >> >> + * SMC call arguments, >> >> + * x0 = THUNDERX2_SMC_CALL_ID (Vendor SMC call Id) >> >> + * x1 = THUNDERX2_SMC_SET_CHANNEL (Id to set DMC/L3C channel) >> >> + * x2 = Node id >> > >> > How do we map Linux node IDs to the firmware's view of node IDs? >> > >> > I don't believe the two are necessarily the same -- Linux's node IDs are >> > a Linux-specific construct. >> >> both are same, it is numa node id from ACPI/firmware. > > I am very wary about assuming that the Linux nid will always be the same > as the ACPI node id. > > For that to *potentially* be true, this driver should depend on > CONFIG_NUMA, NUMA must not be disabled on the command line, etc, or the > node id will always be NUMA_NO_NODE. ok, i can check the node id which we get from ACPI helpers in probe. if it is NUMA_NO_NODE, I will init first socket uncore only and nid param to fw is always zero? > > I would be *much* happier if we had an explicit mapping somewhere to the > ID the FW expects. > >> > It would be much nicer if we could pass something based on the MPIDR, >> > which is a known HW construct, or if this implicitly affected the >> > current node. >> >> IMO, node id is sufficient. > > I agree that *a* node ID is sufficient, I just don't think that we're > guaranteed to have the specific node ID the FW wants. for thunderx2 which is 2 socket only platform, pxm and nid should be same(either 0 or 1) however, i can send PXM id(node_to_pxm) to firmware to make it more sane. > >> > It would be vastly more sane for this to not be muxed at all. :/ >> >> i am helpless due to crappy hw design! > > I'm certainly not blaming you for this! :) > > I hope the HW designers don't make the same mistake in future, though... > > Thanks, > Mark. thanks Ganapat -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
