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AMEVTYPER1<n>_EL0, n = 0 - 15

Activity Monitors Event Type Registers 1

Provides information on the events that an auxiliary activity monitor event counter AMEVCNTR1<n>_EL0 counts.

Configuration

AArch64 System register AMEVTYPER1<n>_EL0 bits [31:0] are architecturally mapped to AArch32 System register AMEVTYPER1<n>[31:0].

AArch64 System register AMEVTYPER1<n>_EL0 bits [31:0] are architecturally mapped to External register AMEVTYPER1<n>[31:0].

This register is present only when FEAT_AMUv1 is implemented. Otherwise, direct accesses to AMEVTYPER1<n>_EL0 are UNDEFINED.

Attributes

AMEVTYPER1<n>_EL0 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0evtCount

Bits [63:16]:

Reserved, RES0.

evtCount, bits [15:0]:

Event to count. The event number of the event that is counted by the auxiliary activity monitor event counter AMEVCNTR1<n>_EL0.

It is IMPLEMENTATION DEFINED what values are supported by each counter.

If software writes a value to this field which is not supported by the corresponding counter AMEVCNTR1<n>_EL0, then:

The event counted by AMEVCNTR1<n>_EL0 might be fixed at implementation. In this case, the field is read-only and writes are UNDEFINED.

If the corresponding counter AMEVCNTR1<n>_EL0 is enabled, writes to this register have UNPREDICTABLE results.

The reset behavior of this field is:

Access Instructions

If <n> is greater than or equal to AMCGCR_EL0.CG1NC or FEAT_AMUv1p1 is implemented and auxiliary counter <n> is not implemented, then reads and writes of AMEVTYPER1<n>_EL0 are UNDEFINED.

Accesses to this register use the following encodings in the System register encoding space:

MRS <Xt>, AMEVTYPER1<m>_EL0 ; Where m = 0-15

(op0 = 0b11, op1 = 0b011, CRn = 0b1101, CRm = 0b111:m[3], op2 = m[2:0])

let m:integer = UInt(CRm[0] :: op2[2:0]); if !IsFeatureImplemented(FEAT_AMUv1) then Undefined(); elsif m >= NUM_AMU_CG1_MONITORS then Undefined(); elsif !IsG1ActivityMonitorImplemented(m) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && CPTR_EL3().TAM == '1' then Undefined(); elsif PSTATE.EL == EL0 then if AMUSERENR_EL0().EN == '0' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EL2Enabled() && CPTR_EL2().TAM == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && EffectivelyAtEL0NotInHost() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HAFGRTR_EL2()[(2 * m) + 19] == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TAM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = AMEVTYPER1_EL0(m); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && CPTR_EL2().TAM == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HAFGRTR_EL2()[(2 * m) + 19] == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TAM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = AMEVTYPER1_EL0(m); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && CPTR_EL3().TAM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = AMEVTYPER1_EL0(m); end; elsif PSTATE.EL == EL3 then X{64}(t) = AMEVTYPER1_EL0(m); end;

MSR AMEVTYPER1<m>_EL0, <Xt> ; Where m = 0-15

(op0 = 0b11, op1 = 0b011, CRn = 0b1101, CRm = 0b111:m[3], op2 = m[2:0])

let m:integer = UInt(CRm[0] :: op2[2:0]); if !IsFeatureImplemented(FEAT_AMUv1) then Undefined(); elsif m >= NUM_AMU_CG1_MONITORS then Undefined(); elsif !IsG1ActivityMonitorImplemented(m) then Undefined(); elsif IsHighestEL(PSTATE.EL) && !ImpDefBool("AMEVCNTR1_EL0()[m] is fixed") then AMEVTYPER1_EL0(m) = X{64}(t); else Undefined(); end;


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