Defines the access permission for each of the sixteen memory domains.
This register is banked between DACR and DACR_S and DACR_NS.
AArch32 System register DACR bits [31:0] are architecturally mapped to AArch64 System register DACR32_EL2[31:0].
This register is present only when FEAT_AA32EL1 is implemented. Otherwise, direct accesses to DACR are UNDEFINED.
This register has no function when TTBCR.EAE is set to 1, to select the Long-descriptor translation table format.
DACR is a 32-bit register.
This register has the following instances:
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 |
D15 | D14 | D13 | D12 | D11 | D10 | D9 | D8 | D7 | D6 | D5 | D4 | D3 | D2 | D1 | D0 |
Domain n access permission, where n = 0 to 15. Permitted values are:
D<n> | Meaning |
---|---|
0b00 |
No access. Any access to the domain generates a Domain fault. |
0b01 |
Client. Accesses are checked against the permission bits in the translation tables. |
0b11 |
Manager. Accesses are not checked against the permission bits in the translation tables. |
The value 0b10 is reserved.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b000 | 0b0011 | 0b0000 | 0b000 |
if !IsFeatureImplemented(FEAT_AA32EL1) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T3 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T3 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2.TRVM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR.TRVM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then R[t] = DACR_NS; else R[t] = DACR; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then R[t] = DACR_NS; else R[t] = DACR; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then R[t] = DACR_S; else R[t] = DACR_NS;
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b000 | 0b0011 | 0b0000 | 0b000 |
if !IsFeatureImplemented(FEAT_AA32EL1) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T3 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T3 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2.TVM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR.TVM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then DACR_NS = R[t]; else DACR = R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then DACR_NS = R[t]; else DACR = R[t]; elsif PSTATE.EL == EL3 then if SCR.NS == '0' && CP15SDISABLE == HIGH then UNDEFINED; elsif SCR.NS == '0' && CP15SDISABLE2 == HIGH then UNDEFINED; else if SCR.NS == '0' then DACR_S = R[t]; else DACR_NS = R[t];