The AMUSERENR_EL0 characteristics are:
Global user enable register for the activity monitors. Enables or disables EL0 access to the activity monitors. AMUSERENR_EL0 is applicable to both the architected and the auxiliary counter groups.
AArch64 System register AMUSERENR_EL0 bits [31:0] are architecturally mapped to AArch32 System register AMUSERENR[31:0].
This register is present only when FEAT_AMUv1 is implemented. Otherwise, direct accesses to AMUSERENR_EL0 are UNDEFINED.
AMUSERENR_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 | EN |
Reserved, RES0.
Traps EL0 accesses to the activity monitors registers to EL1, or to EL2 when it is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, as follows:
In AArch64 state, accesses to the following registers are trapped, reported using EC syndrome value 0x18:
In AArch32 state, MRC and MCR accesses to the following registers are trapped and reported using EC syndrome value 0x03, MRRC and MCRR accesses are trapped and reported using EC syndrome value 0x04:
EN | Meaning |
---|---|
0b0 |
EL0 accesses to the activity monitors registers are trapped. |
0b1 |
This control does not cause any instructions to be trapped. Software can access all activity monitor registers at EL0. |
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b011 | 0b1101 | 0b0010 | 0b011 |
if PSTATE.EL == EL0 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TAM == '1' then UNDEFINED; elsif EL2Enabled() && CPTR_EL2.TAM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3.TAM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return AMUSERENR_EL0; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TAM == '1' then UNDEFINED; elsif EL2Enabled() && CPTR_EL2.TAM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3.TAM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return AMUSERENR_EL0; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TAM == '1' then UNDEFINED; elsif HaveEL(EL3) && CPTR_EL3.TAM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return AMUSERENR_EL0; elsif PSTATE.EL == EL3 then return AMUSERENR_EL0;
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b011 | 0b1101 | 0b0010 | 0b011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TAM == '1' then UNDEFINED; elsif EL2Enabled() && CPTR_EL2.TAM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3.TAM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else AMUSERENR_EL0 = X[t]; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TAM == '1' then UNDEFINED; elsif HaveEL(EL3) && CPTR_EL3.TAM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else AMUSERENR_EL0 = X[t]; elsif PSTATE.EL == EL3 then AMUSERENR_EL0 = X[t];
30/09/2021 15:34; 092b4e1bbfbb45a293b198f9330c5f529ead2b0f
Copyright © 2010-2021 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.