SPMCGCR<n>_EL1 System PMU Counter Group Configuration Registers when FEAT_SPMU is implemented and FEAT_AA64 is implemented 0 1 Describes the configuration of counter groups in System PMU <s>. Unknown SPMCGCR<n>_EL1 is a 64-bit register. N<m> 63 0 63:0 Number of counters in counter group 8n+m. The maximum size of each counter group depends on the number of implemented groups and the largest implemented counter size. For more information, see SPMCFGR_EL1.NCG. 7 0 To access SPMCGCR<n>_EL1 for System PMU <s>, set SPMSELR_EL0.SYSPMUSEL to s. SPMCGCR<n>_EL1 reads-as-zero if any of the following are true: System PMU <s> implements one counter group (SPMCFGR_EL1.NCG is zero). System PMU <s> is not implemented. 0-1 MRS <Xt>, SPMCGCR<m>_EL1 let m:integer = UInt(op2[0]); if !(IsFeatureImplemented(FEAT_SPMU) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then Undefined(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGRTR2_EL2().nSPMID == '0') then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2().EnSPM == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && SPMACCESSR_EL2()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = SPMCGCR_EL1(UInt(SPMSELR_EL0().SYSPMUSEL), m); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then Undefined(); elsif HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = SPMCGCR_EL1(UInt(SPMSELR_EL0().SYSPMUSEL), m); end; elsif PSTATE.EL == EL3 then X{64}(t) = SPMCGCR_EL1(UInt(SPMSELR_EL0().SYSPMUSEL), m); end; 2026-03-26 20:27:25 2026-03_rel