Debug OS Lock Data Transfer Register, Transmit
Used for save/restore of DBGDTRTXint. It is a component of the Debug Communication Channel.
AArch32 System register DBGDTRTXext bits [31:0] are architecturally mapped to AArch64 System register OSDTRTX_EL1[31:0].
This register is present only when FEAT_AA32EL1 is implemented. Otherwise, direct accesses to DBGDTRTXext are UNDEFINED.
DBGDTRTXext is a 32-bit register.
| 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 |
| DTRTX | |||||||||||||||||||||||||||||||
Return DTRTX without side-effect.
Reads of this register return the value in DTRTX and do not change TXfull.
Writes of this register update the value in DTRTX and do not change TXfull.
For the full behavior of the Debug Communications Channel, see 'The Debug Communication Channel and Instruction Transfer Register'.
The reset behavior of this field is:
Arm deprecates reads and writes of DBGDTRTXext through the System register interface when the OS Lock is unlocked, DBGOSLSR.OSLK == 0.
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 = 0b0000, CRm = 0b0011, opc2 = 0b010)
if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif Halted() && PSTATE.EL != EL0 && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then R(t) = DBGDTRTXext(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL2().TDCC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().TDCC == '1' then AArch32_TakeHypTrapException(0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2().[TDE,TDA] != '00' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().[TDE,TDA] != '00' then AArch32_TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else R(t) = DBGDTRTXext(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else R(t) = DBGDTRTXext(); end; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR().TDCC == '1' then AArch32_TakeMonitorTrapException(); else R(t) = DBGDTRTXext(); end; end;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1110, opc1 = 0b000, CRn = 0b0000, CRm = 0b0011, opc2 = 0b010)
if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif Halted() && PSTATE.EL != EL0 && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then DBGDTRTXext() = R(t); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL2().TDCC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().TDCC == '1' then AArch32_TakeHypTrapException(0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2().[TDE,TDA] != '00' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().[TDE,TDA] != '00' then AArch32_TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else DBGDTRTXext() = R(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else DBGDTRTXext() = R(t); end; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR().TDCC == '1' then AArch32_TakeMonitorTrapException(); else DBGDTRTXext() = R(t); end; end;
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