System Performance Monitor Control Register
Main control register for System PMU <s>.
This register is present only when FEAT_SPMU is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to SPMCR_EL0 are UNDEFINED.
SPMCR_EL0 is a 64-bit register.
| 63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| RES0 | |||||||||||||||||||||||||||||||
| RES0 | TRO | HDBG | FZO | NA | RES0 | EX | RES0 | P | E | ||||||||||||||||||||||
Reserved, RES0.
Trace enable. For more information on this field, see 'CoreSight PMU Architecture'.
The reset behavior of this field is:
Accessing this field has the following behavior:
Reserved, RES0.
Halt-on-debug. For more information on this field, see 'CoreSight PMU Architecture'.
The reset behavior of this field is:
Accessing this field has the following behavior:
Reserved, RES0.
Freeze-on-overflow. For more information on this field, see 'CoreSight PMU Architecture'.
If implemented by a System PMU, then freeze-on-overflow affects only the counters of System PMU <s>, not other System PMUs nor the PE PMU.
The reset behavior of this field is:
Reserved, RES0.
Not accessible. For more information on this field, see 'CoreSight PMU Architecture'.
Access to this field is RO.
Reserved, RES0.
Reserved, RES0.
Export enable. For more information on this field, see 'CoreSight PMU Architecture'.
The reset behavior of this field is:
Reserved, RES0.
Reserved, RES0.
Event counter reset.
| P | Meaning |
|---|---|
| 0b0 |
Write is ignored. |
| 0b1 |
Reset all event counters in System PMU <s> to zero. |
Resetting the event counters does not affect any overflow flags.
Access to this field is WO/RAZ.
Count enable. This field controls System PMU <s>.
| E | Meaning |
|---|---|
| 0b0 |
Monitor is disabled. |
| 0b1 |
Monitor is enabled. |
Performance monitor overflow IRQs are only signaled by System PMU <s> when this field is 1.
The reset behavior of this field is:
To access SPMCR_EL0 for System PMU <s>, set SPMSELR_EL0.SYSPMUSEL to s.
SPMCR_EL0 reads-as-zero and ignores writes if System PMU <s> is not implemented.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, SPMCR_EL0
(op0 = 0b10, op1 = 0b011, CRn = 0b1001, CRm = 0b1100, op2 = 0b000)
if !(IsFeatureImplemented(FEAT_SPMU) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then Undefined(); elsif PSTATE.EL == EL0 then if MDSCR_EL1().EnSPM == '0' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EffectivelyAtEL0NotInHost() && SPMACCESSR_EL1()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] == '00' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EL2Enabled() && EffectivelyAtEL0NotInHost() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGRTR2_EL2().nSPMCR_EL0 == '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) = SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGRTR2_EL2().nSPMCR_EL0 == '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) = SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)); end; elsif PSTATE.EL == EL2 then if 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) = SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)); end; elsif PSTATE.EL == EL3 then X{64}(t) = SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)); end;
MSR SPMCR_EL0, <Xt>
(op0 = 0b10, op1 = 0b011, CRn = 0b1001, CRm = 0b1100, op2 = 0b000)
if !(IsFeatureImplemented(FEAT_SPMU) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && SPMACCESSR_EL3()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] != '11' then Undefined(); elsif PSTATE.EL == EL0 then if MDSCR_EL1().EnSPM == '0' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EffectivelyAtEL0NotInHost() && SPMACCESSR_EL1()[UInt(SPMSELR_EL0().SYSPMUSEL) * 2+:2] != '11' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EL2Enabled() && EffectivelyAtEL0NotInHost() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGWTR2_EL2().nSPMCR_EL0 == '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] != '11' 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] != '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)) = X{64}(t); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGWTR2_EL2().nSPMCR_EL0 == '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] != '11' 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] != '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)) = X{64}(t); end; elsif PSTATE.EL == EL2 then if 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] != '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)) = X{64}(t); end; elsif PSTATE.EL == EL3 then SPMCR_EL0(UInt(SPMSELR_EL0().SYSPMUSEL)) = X{64}(t); end;
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