Hi James, On 9/10/25 21:42, James Morse wrote: > The bulk of the MPAM driver lives outside the arch code because it > largely manages MMIO devices that generate interrupts. The driver > needs a Kconfig symbol to enable it. As MPAM is only found on arm64 > platforms, the arm64 tree is the most natural home for the Kconfig > option. > > This Kconfig option will later be used by the arch code to enable > or disable the MPAM context-switch code, and to register properties > of CPUs with the MPAM driver. > > Signed-off-by: James Morse <james.morse@xxxxxxx> > Reviewed-by: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx> > CC: Dave Martin <dave.martin@xxxxxxx> > --- > Changes since v1: > * Help text rewritten by Dave. > --- > arch/arm64/Kconfig | 23 +++++++++++++++++++++++ > 1 file changed, 23 insertions(+) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index e9bbfacc35a6..4be8a13505bf 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -2060,6 +2060,29 @@ config ARM64_TLB_RANGE > ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a > range of input addresses. > > +config ARM64_MPAM > + bool "Enable support for MPAM" > + help > + Memory System Resource Partitioning and Monitoring (MPAM) is an > + optional extension to the Arm architecture that allows each > + transaction issued to the memory system to be labelled with a > + Partition identifier (PARTID) and Performance Monitoring Group > + identifier (PMG). > + > + Memory system components, such as the caches, can be configured with > + policies to control how much of various physical resources (such as > + memory bandwidth or cache memory) the transactions labelled with each > + PARTID can consume. Depending on the capabilities of the hardware, > + the PARTID and PMG can also be used as filtering criteria to measure > + the memory system resource consumption of different parts of a > + workload. > + > + Use of this extension requires CPU support, support in the > + Memory System Components (MSC), and a description from firmware > + of where the MSCs are in the address space. > + > + MPAM is exposed to user-space via the resctrl pseudo filesystem. > + > endmenu # "ARMv8.4 architectural features" > > menu "ARMv8.5 architectural features" Seems good to me. I guess we can consider separately whether we want this to be default or not. Reviewed-by: Ben Horgan <ben.horgan@xxxxxxx> Thanks, Ben
