The HACTLR2 characteristics are:
Provides additional space to the HACTLR register to hold IMPLEMENTATION DEFINED trap functionality.
AArch32 System register HACTLR2 bits [31:0] are architecturally mapped to AArch64 System register ACTLR_EL2[63:32].
This register is present only when AArch32 is supported at any Exception level. Otherwise, direct accesses to HACTLR2 are UNDEFINED.
In Armv8.0 and Armv8.1, it is IMPLEMENTATION DEFINED whether this register is implemented, or whether it causes UNDEFINED exceptions when accessed. The implementation of this register can be detected by examining ID_MMFR4.AC2.
From Armv8.2 this register must be implemented.
HACTLR2 is a 32-bit register.
The HACTLR2 bit assignments are:
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 |
IMPLEMENTATION DEFINED |
IMPLEMENTATION DEFINED.
On a Warm reset, this field resets to an architecturally UNKNOWN value.
Accesses to this register use the following encodings:
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b100 | 0b0001 | 0b0000 | 0b011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T1 == '1' then AArch32.TakeHypTrapException(0x03); else UNDEFINED; elsif PSTATE.EL == EL2 then return HACTLR2; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else return HACTLR2;
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b100 | 0b0001 | 0b0000 | 0b011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T1 == '1' then AArch32.TakeHypTrapException(0x03); else UNDEFINED; elsif PSTATE.EL == EL2 then HACTLR2 = R[t]; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else HACTLR2 = R[t];
30/03/2021 20:51; e3551d56dc294a4d55296a6c10544191ada08a8e
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