Debug Self Address Register
In earlier versions of the Arm Architecture, this register defines the offset from the base address defined in DBGDRAR of the physical base address of the debug registers for the PE. Use of this register is deprecated.
This register is present only when FEAT_AA32 is implemented. Otherwise, direct accesses to DBGDSAR are UNDEFINED.
DBGDSAR is a 64-bit register that can also be accessed as a 32-bit value. If it is accessed as a 32-bit register, bits [31:0] are read.
If EL1 cannot use AArch32 then the implementation of this register is OPTIONAL and deprecated.
DBGDSAR 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 | RAZ | ||||||||||||||||||||||||||||||
Reserved, RES0.
Reserved, RAZ.
This field indicates whether the debug self address offset is valid. For ARMv8, this field is always 0b00, the offset is not valid.
Accesses to this register use the following encodings in the System register encoding space:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1110, opc1 = 0b000, CRn = 0b0010, CRm = 0b0000, opc2 = 0b000)
if !IsFeatureImplemented(FEAT_AA32) then UNDEFINED; elsif Halted() && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then R[t] = DBGDSAR<31:0>; elsif PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif IsFeatureImplemented(FEAT_AA64EL1) && !ELUsingAArch32(EL1) && MDSCR_EL1.TDCC == '1' then if EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x05); else AArch64.AArch32SystemAccessTrap(EL1, 0x05); elsif IsFeatureImplemented(FEAT_AA32EL1) && ELUsingAArch32(EL1) && DBGDSCRext.UDCCdis == '1' then if EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2)) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && (HCR_EL2.TGE == '1' || MDCR_EL2.<TDE,TDRA> != '00') then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2)) && (HCR.TGE == '1' || HDCR.<TDE,TDRA> != '00') then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else R[t] = DBGDSAR<31:0>; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDRA> != '00' then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR.<TDE,TDRA> != '00' then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else R[t] = DBGDSAR<31:0>; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else R[t] = DBGDSAR<31:0>; elsif PSTATE.EL == EL3 then R[t] = DBGDSAR<31:0>;
MRRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <Rt2>, <CRm>
(coproc = 0b1110, CRm = 0b0010, opc1 = 0b0000)
if !IsFeatureImplemented(FEAT_AA32) then UNDEFINED; elsif Halted() && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then (R[t2], R[t]) = Split(DBGDSAR, 32); elsif PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif IsFeatureImplemented(FEAT_AA64EL1) && !ELUsingAArch32(EL1) && MDSCR_EL1.TDCC == '1' then if EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x0C); else AArch64.AArch32SystemAccessTrap(EL1, 0x0C); elsif IsFeatureImplemented(FEAT_AA32EL1) && ELUsingAArch32(EL1) && DBGDSCRext.UDCCdis == '1' then if EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x0C); elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2)) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2)) && (HCR_EL2.TGE == '1' || MDCR_EL2.<TDE,TDRA> != '00') then AArch64.AArch32SystemAccessTrap(EL2, 0x0C); elsif EL2Enabled() && (IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2)) && (HCR.TGE == '1' || HDCR.<TDE,TDRA> != '00') then AArch32.TakeHypTrapException(0x0C); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x0C); else (R[t2], R[t]) = Split(DBGDSAR, 32); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDRA> != '00' then AArch64.AArch32SystemAccessTrap(EL2, 0x0C); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR.<TDE,TDRA> != '00' then AArch32.TakeHypTrapException(0x0C); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x0C); else (R[t2], R[t]) = Split(DBGDSAR, 32); elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x0C); else (R[t2], R[t]) = Split(DBGDSAR, 32); elsif PSTATE.EL == EL3 then (R[t2], R[t]) = Split(DBGDSAR, 32);
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