ESR_EL1 Exception Syndrome Register (EL1) DFSR Architectural AArch32 31 0 31 0 Holds syndrome information for an exception taken to EL1. Exception and fault handling registers ESR_EL1 is a 64-bit register. ESR_EL1 is made UNKNOWN as a result of an exception return from EL1. When an UNPREDICTABLE instruction is treated as UNDEFINED, and the exception is taken to EL1, the value of ESR_EL1 is UNKNOWN. The value written to ESR_EL1 must be consistent with a value that could be created as a result of an exception from the same Exception level that generated the exception as a result of a situation that is not UNPREDICTABLE at that Exception level, in order to avoid the possibility of a privilege violation. 0 63 32 Reserved, RES0. EC 31 26 Exception Class. Indicates the reason for the exception that this register holds information about. For each EC value, the table references a subsection that gives information about: The cause of the exception, for example the configuration required to enable the trap. The encoding of the associated ISS. Possible values of the EC field are: 0b000000 Unknown reason. 0b000001 Trapped WFI or WFE instruction execution. Conditional WFE and WFI instructions that fail their condition code check do not cause an exception. 0b000011 Trapped MCR or MRC access with (coproc==0b1111) that is not reported using EC 0b000000. 0b000100 Trapped MCRR or MRRC access with (coproc==0b1111) that is not reported using EC 0b000000. 0b000101 Trapped MCR or MRC access with (coproc==0b1110). 0b000110 Trapped LDC or STC access. The only architected uses of these instruction are: An STC to write data to memory from DBGDTRRXint. An LDC to read data from memory to DBGDTRTXint. 0b000111 Access to SVE, Advanced SIMD, or floating-point functionality trapped by CPACR_EL1.FPEN, CPTR_EL2.FPEN, CPTR_EL2.TFP, or CPTR_EL3.TFP control. Excludes exceptions resulting from CPACR_EL1 when the value of HCR_EL2.TGE is 1, or because SVE or Advanced SIMD and floating-point are not implemented. These are reported with EC value 0b000000 as described in . 0b001100 Trapped MRRC access with (coproc==0b1110). 0b001101 Branch Target Exception. When ARMv8.5-BTI is implemented 0b001110 Illegal Execution state. 0b010001 SVC instruction execution in AArch32 state. This is reported in ESR_EL2 only when the exception is generated because the value of HCR_EL2.TGE is 1. 0b010101 SVC instruction execution in AArch64 state. 0b011000 Trapped MSR, MRS or System instruction execution in AArch64 state, that is not reported using EC 0b000000, 0b000001 or 0b000111. If is implemented, also exceptions generated on a read of an ID register. If is implemented, also Cache Speculation Variant exceptions. This includes all instructions that cause exceptions that are part of the encoding space defined in , except for those exceptions reported using EC values 0b000000, 0b000001, or 0b000111. 0b011001 Access to SVE functionality trapped as a result of CPACR_EL1.ZEN, CPTR_EL2.ZEN, CPTR_EL2.TZ, or CPTR_EL3.EZ, that is not reported using EC 0b000000. This EC is defined only if is implemented. 0b100000 Instruction Abort from a lower Exception level, that might be using AArch32 or AArch64. Used for MMU faults generated by instruction accesses and synchronous External aborts, including synchronous parity or ECC errors. Not used for debug related exceptions. 0b100001 Instruction Abort taken without a change in Exception level. Used for MMU faults generated by instruction accesses and synchronous External aborts, including synchronous parity or ECC errors. Not used for debug related exceptions. 0b100010 PC alignment fault exception. 0b100100 Data Abort from a lower Exception level, that might be using AArch32 or AArch64. Used for MMU faults generated by data accesses, alignment faults other than those caused by Stack Pointer misalignment, and synchronous External aborts, including synchronous parity or ECC errors. Not used for debug related exceptions. 0b100101 Data Abort taken without a change in Exception level. Used for MMU faults generated by data accesses, alignment faults other than those caused by Stack Pointer misalignment, and synchronous External aborts, including synchronous parity or ECC errors. Not used for debug related exceptions. 0b100110 SP alignment fault exception. 0b101000 Trapped floating-point exception taken from AArch32 state. This EC value is valid if the implementation supports trapping of floating-point exceptions, otherwise it is reserved. Whether a floating-point implementation supports trapping of floating-point exceptions is IMPLEMENTATION DEFINED. 0b101100 Trapped floating-point exception taken from AArch64 state. This EC value is valid if the implementation supports trapping of floating-point exceptions, otherwise it is reserved. Whether a floating-point implementation supports trapping of floating-point exceptions is IMPLEMENTATION DEFINED. 0b101111 SError interrupt. 0b110000 Breakpoint exception from a lower Exception level, that might be using AArch32 or AArch64. 0b110001 Breakpoint exception taken without a change in Exception level. 0b110010 Software Step exception from a lower Exception level, that might be using AArch32 or AArch64. 0b110011 Software Step exception taken without a change in Exception level. 0b110100 Watchpoint exception from a lower Exception level, that might be using AArch32 or AArch64. 0b110101 Watchpoint exception taken without a change in Exception level. 0b111000 BKPT instruction execution in AArch32 state. 0b111100 BRK instruction execution in AArch64 state. This is reported in ESR_EL3 only if a BRK instruction is executed. All other EC values are reserved by Arm, and: Unused values in the range 0b000000 - 0b101100 (0x00 - 0x2C) are reserved for future use for synchronous exceptions. Unused values in the range 0b101101 - 0b111111 (0x2D - 0x3F) are reserved for future use, and might be used for synchronous or asynchronous exceptions. The effect of programming this field to a reserved value is that behavior is CONSTRAINED UNPREDICTABLE, as described in . U IL 25 25 Instruction Length for synchronous exceptions. Possible values of this bit are: 0b0 16-bit instruction trapped. 0b1 An SError interrupt. An Instruction Abort exception. A PC alignment fault exception. An SP alignment fault exception. A Data Abort exception for which the value of the ISV bit is 0. An Illegal Execution state exception. Any debug exception except for Breakpoint instruction exceptions. For Breakpoint instruction exceptions, this bit has its standard meaning: 0b0: 16-bit T32 BKPT instruction. 0b1: 32-bit A32 BKPT instruction or A64 BRK instruction. An exception reported using EC value 0b000000. U ISS 24 0 Instruction Specific Syndrome. Architecturally, this field can be defined independently for each defined Exception class. However, in practice, some ISS encodings are used for more than one Exception class. Typically, an ISS encoding has a number of subfields. When an ISS subfield holds a register number, the value returned in that field is the AArch64 view of the register number. For an exception taken from AArch32 state, defines this view of the specified AArch32 register. If the AArch32 register descriptor is 0b1111, then: If the instruction that generated the exception was not UNPREDICTABLE, the field takes the value 0b11111. If the instruction that generated the exception was UNPREDICTABLE, the field takes an UNKNOWN value that must be either: The AArch64 view of the register number of a register that might have been used at the Exception level from which the exception was taken. The value 0b11111. When the EC field is 0b000000, indicating an exception with an unknown reason, the ISS field is not valid, RES0. I Exceptions with an unknown reason 0 24 0 Reserved, RES0. When an exception is reported using this EC code the IL field is set to 1. This EC code is used for all exceptions that are not covered by any other EC value. This includes exceptions that are generated in the following situations: The attempted execution of an instruction bit pattern that has no allocated instruction at the current Exception level and Security state, including: A read access using a System register pattern that is not allocated for reads at the current Exception level and Security state. A write access using a System register pattern that is not allocated for writes at the current Exception level and Security state. Instruction encodings for instructions not implemented in the implementation. In Debug state, the attempted execution of an instruction bit pattern that is unallocated in Debug state. In Non-debug state, the attempted execution of an instruction bit pattern that is unallocated in Non-debug state. In AArch32 state, attempted execution of a short vector floating-point instruction. In an implementation that does not include Advanced SIMD and floating-point functionality, an attempted access to Advanced SIMD or floating-point functionality under conditions where that access would be permitted if that functionality was present. This includes the attempted execution of an Advanced SIMD or floating-point instruction, and attempted accesses to Advanced SIMD and floating-point System registers. An exception generated because of the value of one of the SCTLR_EL1.{ITD, SED, CP15BEN} control bits. Attempted execution of: An HVC instruction when disabled by HCR_EL2.HCD or SCR_EL3.HCE. An SMC instruction when disabled by SCR_EL3.SMD. An HLT instruction when disabled by EDSCR.HDE. Attempted execution of an MSR or MRS instruction to access SP_EL0 when the value of SPSel.SP is 0. Attempted execution, in Debug state, of: A DCPS1 instruction when the value of HCR_EL2.TGE is 1 and EL2 is disabled or not implemented in the current Security state. A DCPS2 instruction from EL1 or EL0 when EL2 is disabled or not implemented in the current Security state. A DCPS3 instruction when the value of EDSCR.SDD is 1, or when EL3 is not implemented. When EL3 is using AArch64, attempted execution from Secure EL1 of an SRS instruction using R13_mon. See . In Debug state when the value of EDSCR.SDD is 1, the attempted execution at EL2, EL1, or EL0 of an instruction that is configured to trap to EL3. In AArch32 state, the attempted execution of an MRS (banked register) or an MSR (banked register) instruction to SPSR_mon, SP_mon, or LR_mon. An exception that is taken to EL2 because the value of HCR_EL2.TGE is 1 that, if the value of HCR_EL2.TGE was 0 would have been reported with an ESR_ELx.EC value of 0b000111. When SVE is not implemented, attempted execution of: An SVE instruction. An MSR or MRS instruction to access ZCR_EL1, ZCR_EL2, or ZCR_EL3. Exception from a WFI or WFE instruction CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. U 0 19 1 Reserved, RES0. TI 0 0 Trapped instruction. Possible values of this bit are: 0b0 WFI trapped. 0b1 WFE trapped. U The following sections describe configuration settings for generating this exception: . . . Exception from an MCR or MRC access CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. U Opc2 19 17 The Opc2 value from the issued instruction. For a trapped VMRS access, holds the value 0b000. U Opc1 16 14 The Opc1 value from the issued instruction. For a trapped VMRS access, holds the value 0b111. U CRn 13 10 The CRn value from the issued instruction. For a trapped VMRS access, holds the reg field from the VMRS instruction encoding. U Rt 9 5 The Rt value from the issued instruction, the general-purpose register used for the transfer. The reported value gives the AArch64 view of the register. See . U CRm 4 1 The CRm value from the issued instruction. For a trapped VMRS access, holds the value 0b0000. U Direction 0 0 Indicates the direction of the trapped instruction. The possible values of this bit are: 0b0 Write to System register space. MCR instruction. 0b1 Read from System register space. MRC or VMRS instruction. U The following sections describe configuration settings for generating exceptions that are reported using EC value 0b000011: . . . . . . . . . . . . . . . . The following sections describe configuration settings for generating exceptions that are reported using EC value 0b000101: . . , for trapped accesses to the JIDR. . . . . . . . describes configuration settings for generating exceptions that are reported using EC value 0b001000. Exception from an MCRR or MRRC access CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. U Opc1 19 16 The Opc1 value from the issued instruction. U 0 15 15 Reserved, RES0. Rt2 14 10 The Rt2 value from the issued instruction, the second general-purpose register used for the transfer. The reported value gives the AArch64 view of the register. See . U Rt 9 5 The Rt value from the issued instruction, the first general-purpose register used for the transfer. The reported value gives the AArch64 view of the register. See . U CRm 4 1 The CRm value from the issued instruction. U Direction 0 0 Indicates the direction of the trapped instruction. The possible values of this bit are: 0b0 Write to System register space. MCRR instruction. 0b1 Read from System register space. MRRC instruction. U The following sections describe configuration settings for generating exceptions that are reported using EC value 0b000100: . . . . . . . . . . The following sections describe configuration settings for generating exceptions that are reported using EC value 0b001100: . . . . . . . Exception from an LDC or STC instruction CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. U imm8 19 12 The immediate value from the issued instruction. U 0 11 10 Reserved, RES0. Rn 9 5 The Rn value from the issued instruction, the general-purpose register used for the transfer. The reported value gives the AArch64 view of the register. See . This field is valid only when AM[2] is 0, indicating an immediate form of the LDC or STC instruction. When AM[2] is 1, indicating a literal form of the LDC or STC instruction, this field is UNKNOWN. U Offset 4 4 Indicates whether the offset is added or subtracted: 0b0 Subtract offset. 0b1 Add offset. This bit corresponds to the U bit in the instruction encoding. U AM 3 1 Addressing mode. The permitted values of this field are: 0b000 Immediate unindexed. 0b001 Immediate post-indexed. 0b010 Immediate offset. 0b011 Immediate pre-indexed. 0b100 For a trapped STC instruction or a trapped T32 LDC instruction this encoding is reserved. 0b110 For a trapped STC instruction, this encoding is reserved. The values 0b101 and 0b111 are reserved. The effect of programming this field to a reserved value is that behavior is CONSTRAINED UNPREDICTABLE, as described in . Bit [2] in this subfield indicates the instruction form, immediate or literal. Bits [1:0] in this subfield correspond to the bits {P, W} in the instruction encoding. U Direction 0 0 Indicates the direction of the trapped instruction. The possible values of this bit are: 0b0 Write to memory. STC instruction. 0b1 Read from memory. LDC instruction. U The following sections describe the configuration settings for the traps that are reported using EC value 0b000110: . . . Exception from an access to SVE, Advanced SIMD or floating-point functionality, resulting from CPACR_EL1.FPEN, CPTR_EL2.FPEN or CPTR_ELx.TFP The accesses covered by this trap include: Execution of SVE or Advanced SIMD and floating-point instructions. Accesses to the Advanced SIMD and floating-point System registers. For an implementation that does not include either SVE or support for floating-point and Advanced SIMD, the exception is reported using the EC value 0b000000. CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. U 0 19 0 Reserved, RES0. The following sections describe the configuration settings for the traps that are reported using EC value 0b000111: . . Exception from an access to SVE functionality, resulting from CPACR_EL1.ZEN, CPTR_EL2.ZEN, CPTR_EL2.TZ, or CPTR_EL3.EZ 0 24 0 Reserved, RES0. When SVE is implemented 0 24 0 Reserved, RES0. The accesses covered by this trap include: Execution of SVE instructions. Accesses to the SVE system registers, ZCR_ELx and ID_AA64ZFR0_EL1. For an implementation that does not include SVE, the exception is reported using the EC value 0b000000. Exception from an Illegal Execution state, or a PC or SP alignment fault 0 24 0 Reserved, RES0. There are no configuration settings for generating Illegal Execution state exceptions and PC alignment fault exceptions. For more information about these exceptions see and . describes the configuration settings for generating SP alignment fault exceptions. Exception from HVC or SVC instruction execution 0 24 16 Reserved, RES0. imm16 15 0 The value of the immediate field from the HVC or SVC instruction. For an HVC instruction, and for an A64 SVC instruction, this is the value of the imm16 field of the issued instruction. For an A32 or T32 SVC instruction: If the instruction is unconditional, then: For the T32 instruction, this field is zero-extended from the imm8 field of the instruction. For the A32 instruction, this field is the bottom 16 bits of the imm24 field of the instruction. If the instruction is conditional, this field is UNKNOWN. U In AArch32 state, the HVC instruction is unconditional, and a conditional SVC instruction generates an exception only if it passes its condition code check. Therefore, the syndrome information for these exceptions does not require conditionality information. For T32 and A32 instructions, see and . For A64 instructions, see and . Exception from SMC instruction execution in AArch32 state For an SMC instruction that completes normally and generates an exception that is taken to EL3, the ISS encoding is RES0. For an SMC instruction that is trapped to EL2 from EL1 because HCR_EL2.TSC is 1, the ISS encoding is as shown in the diagram. CV 24 24 Condition code valid. Possible values of this bit are: 0b0 The COND field is not valid. 0b1 The COND field is valid. For exceptions taken from AArch64, CV is set to 1. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether CV is set to 1 or set to 0. See the description of the COND field for more information. This field is only valid if CCKNOWNPASS is 1, otherwise it is RES0. U COND 23 20 The condition code for the trapped instruction. This field is valid only for exceptions taken from AArch32, and only when the value of CV is 1. For exceptions taken from AArch64, this field is set to 0b1110. For exceptions taken from AArch32: When an A32 instruction is trapped, CV is set to 1 and: If the instruction is conditional, COND is set to the condition code field value from the instruction. If the instruction is unconditional, COND is set to 0b1110. A conditional A32 instruction that is known to pass its condition code check can be presented either: With COND set to 0b1110, the value for unconditional. With the COND value held in the instruction. When a T32 instruction is trapped, it is IMPLEMENTATION DEFINED whether: CV is set to 0 and COND is set to an UNKNOWN value. Software must examine the SPSR.IT field to determine the condition, if any, of the T32 instruction. CV is set to 1 and COND is set to the condition code for the condition that applied to the instruction. For an implementation that, for both A32 and T32 instructions, takes an exception on a trapped conditional instruction only if the instruction passes its condition code check, these definitions mean that when CV is set to 1 it is IMPLEMENTATION DEFINED whether the COND field is set to 0b1110, or to the value of any condition that applied to the instruction. This field is only valid if CCKNOWNPASS is 1, otherwise it is RES0. U CCKNOWNPASS 19 19 Indicates whether the instruction might have failed its condition code check. 0b0 The instruction was unconditional, or was conditional and passed its condition code check. 0b1 The instruction was conditional, and might have failed its condition code check. In an implementation in which an SMC instruction that fails it code check is not trapped, this field can always return the value 0. U 0 18 0 Reserved, RES0. describes the configuration settings for trapping SMC instructions from EL1 modes, and describes the case where these exceptions are trapped to EL3. Exception from SMC instruction execution in AArch64 state 0 24 16 Reserved, RES0. imm16 15 0 The value of the immediate field from the issued SMC instruction. U The value of ISS[24:0] described here is used both: When an SMC instruction is trapped from EL1 modes. When an SMC instruction is not trapped, so completes normally and generates an exception that is taken to EL3. describes the configuration settings for trapping SMC instructions from Non-secure EL1 modes, and describes the case where these exceptions are trapped to EL3. Exception from MSR, MRS, or System instruction execution in AArch64 state 0 24 22 Reserved, RES0. Op0 21 20 The Op0 value from the issued instruction. U Op2 19 17 The Op2 value from the issued instruction. U Op1 16 14 The Op1 value from the issued instruction. U CRn 13 10 The CRn value from the issued instruction. U Rt 9 5 The Rt value from the issued instruction, the general-purpose register used for the transfer. U CRm 4 1 The CRm value from the issued instruction. U Direction 0 0 Indicates the direction of the trapped instruction. The possible values of this bit are: 0b0 Write access, including MSR instructions. 0b1 Read access, including MRS instructions. U For exceptions caused by System instructions, see for the encoding values returned by an instruction. The following sections describe configuration settings for generating the exception that is reported using EC value 0b011000: In . . . . . . . . . . In . . . . . . . . . . . . . . . . . . . . In . . . . . . . . IMPLEMENTATION DEFINED exception to EL3 IMPLEMENTATION DEFINED 24 0 IMPLEMENTATION DEFINED. I U Exception from an Instruction Abort 0 24 13 Reserved, RES0. SET 12 11 Synchronous Error Type. When the RAS Extension is implemented and IFSC is 0b010000, describes the state of the PE after taking the Instruction Abort exception. The possible values of this field are: 0b00 Recoverable error (UER). 0b10 Uncontainable error (UC). 0b11 Restartable error (UEO) or Corrected error (CE). All other values are reserved. Software can use this information to determine what recovery might be possible. Taking a synchronous External Abort exception might result in an unrecoverable PE state.This field is RES0 if either: The RAS Extension is not implemented. The value returned in the IFSC field is not 0b010000. U FnV 10 10 FAR not Valid, for a synchronous External abort other than a synchronous External abort on a translation table walk. 0b0 FAR is valid. 0b1 FAR is not valid, and holds an UNKNOWN value. This field is only valid if the IFSC code is 0b010000. It is RES0 for all other aborts. U EA 9 9 External abort type. This bit can provide an IMPLEMENTATION DEFINED classification of External aborts. For any abort other than an External abort this bit returns a value of 0. U 0 8 8 Reserved, RES0. S1PTW 7 7 For a stage 2 fault, indicates whether the fault was a stage 2 fault on an access made for a stage 1 translation table walk: 0b0 Fault not on a stage 2 translation for a stage 1 translation table walk. 0b1 Fault on the stage 2 translation of an access for a stage 1 translation table walk. For any abort other than a stage 2 fault this bit is RES0. U 0 6 6 Reserved, RES0. IFSC 5 0 Instruction Fault Status Code. Possible values of this field are: 0b000000 Address size fault, level 0 of translation or translation table base register 0b000001 Address size fault, level 1 0b000010 Address size fault, level 2 0b000011 Address size fault, level 3 0b000100 Translation fault, level 0 0b000101 Translation fault, level 1 0b000110 Translation fault, level 2 0b000111 Translation fault, level 3 0b001001 Access flag fault, level 1 0b001010 Access flag fault, level 2 0b001011 Access flag fault, level 3 0b001101 Permission fault, level 1 0b001110 Permission fault, level 2 0b001111 Permission fault, level 3 0b010000 Synchronous External abort, not on translation table walk 0b010100 Synchronous External abort, on translation table walk, level 0 0b010101 Synchronous External abort, on translation table walk, level 1 0b010110 Synchronous External abort, on translation table walk, level 2 0b010111 Synchronous External abort, on translation table walk, level 3 0b011000 Synchronous parity or ECC error on memory access, not on translation table walk 0b011100 Synchronous parity or ECC error on memory access on translation table walk, level 0 0b011101 Synchronous parity or ECC error on memory access on translation table walk, level 1 0b011110 Synchronous parity or ECC error on memory access on translation table walk, level 2 0b011111 Synchronous parity or ECC error on memory access on translation table walk, level 3 0b110000 TLB conflict abort 0b110001 Unsupported atomic hardware update fault, if the implementation includes . Otherwise reserved. All other values are reserved. When the RAS Extension is implemented, 0b011000, 0b011100, 0b011101, 0b011110, and 0b011111, are reserved. Armv8.2 requires the implementation of the RAS Extension.For more information about the lookup level associated with a fault, see . Because Access flag faults and Permission faults can only result from a Block or Page translation table descriptor, they cannot occur at level 0.If the S1PTW bit is set, then the level refers the level of the stage2 translation that is translating a stage 1 translation walk. U Exception from a Data Abort ISV 24 24 Instruction syndrome valid. Indicates whether the syndrome information in ISS[23:0] is valid. 0b0 No valid instruction syndrome. ISS[23:14] are RES0. 0b1 ISS[23:14] hold a valid instruction syndrome. This bit is 0 for all faults reported in ESR_EL2 except the following stage 2 aborts: AArch64 loads and stores of a single general-purpose register (including the register specified with 0b11111, including those with Acquire/Release semantics, but excluding Load Exclusive or Store Exclusive and excluding those with writeback. AArch32 instructions where the instruction: Is an LDR, LDA, LDRT, LDRSH, LDRSHT, LDRH, LDAH, LDRHT, LDRSB, LDRSBT, LDRB, LDAB, LDRBT, STR, STL, STRT, STRH, STLH, STRHT, STRB, STLB, or STRBT instruction. Is not performing register writeback. Is not using R15 as a source or destination register. For these cases, ISV is UNKNOWN if the exception was generated in Debug state in memory access mode, and otherwise indicates whether ISS[23:14] hold a valid syndrome. ISV is 0 for all faults reported in ESR_EL1 or ESR_EL3. When the RAS Extension is implemented, ISV is 0 for any synchronous External abort. For ISS reporting, a stage 2 abort on a stage 1 translation table walk does not return a valid instruction syndrome, and therefore ISV is 0 for these aborts. When the RAS Extension is not implemented, the value of ISV on a synchronous External abort on a stage 2 translation table walk is IMPLEMENTATION DEFINED. U SAS 23 22 Syndrome Access Size. When ISV is 1, indicates the size of the access attempted by the faulting operation. 0b00 Byte 0b01 Halfword 0b10 Word 0b11 Doubleword This field is UNKNOWN when the value of ISV is UNKNOWN. This field is RES0 when the value of ISV is 0. U SSE 21 21 Syndrome Sign Extend. When ISV is 1, for a byte, halfword, or word load operation, indicates whether the data item must be sign extended. For these cases, the possible values of this bit are: 0b0 Sign-extension not required. 0b1 Data item must be sign-extended. For all other operations this bit is 0. This field is UNKNOWN when the value of ISV is UNKNOWN. This field is RES0 when the value of ISV is 0. U SRT 20 16 Syndrome Register transfer. When ISV is 1, the register number of the Rt operand of the faulting instruction. If the exception was taken from an Exception level that is using AArch32 then this is the AArch64 view of the register. See . This field is UNKNOWN when the value of ISV is UNKNOWN. This field is RES0 when the value of ISV is 0. U SF 15 15 Width of the register accessed by the instruction is Sixty-Four. When ISV is 1, the possible values of this bit are: 0b0 Instruction loads/stores a 32-bit wide register. 0b1 Instruction loads/stores a 64-bit wide register. This field specifies the register width identified by the instruction, not the Execution state.This field is UNKNOWN when the value of ISV is UNKNOWN. This field is RES0 when the value of ISV is 0. U AR 14 14 Acquire/Release. When ISV is 1, the possible values of this bit are: 0b0 Instruction did not have acquire/release semantics. 0b1 Instruction did have acquire/release semantics. This field is UNKNOWN when the value of ISV is UNKNOWN. This field is RES0 when the value of ISV is 0. U VNCR 13 13 Indicates that the fault came from use of VNCR_EL2 register by EL1 code. 0b0 The fault was not generated by the use of VNCR_EL2, by an MRS or MSR instruction executed at EL1. 0b1 The fault was generated by the use of VNCR_EL2, by an MRS or MSR instruction executed at EL1. This field is 0 in ESR_EL1. U When ARMv8.4-NV is implemented 0 13 13 Reserved, RES0. SET 12 11 Synchronous Error Type. When the RAS Extension is implemented and DFSC is 0b010000, describes the state of the PE after taking the Data Abort exception. The possible values of this field are: 0b00 Recoverable error (UER). 0b10 Uncontainable error (UC). 0b11 Restartable error (UEO) or Corrected error (CE). All other values are reserved. Software can use this information to determine what recovery might be possible. Taking a synchronous External Abort exception might result in an unrecoverable PE state.This field is RES0 if either: The RAS Extension is not implemented. The value returned in the DFSC field is not 0b010000. U FnV 10 10 FAR not Valid, for a synchronous External abort other than a synchronous External abort on a translation table walk. 0b0 FAR is valid. 0b1 FAR is not valid, and holds an UNKNOWN value. This field is valid only if the DFSC code is 0b010000. It is RES0 for all other aborts. U EA 9 9 External abort type. This bit can provide an IMPLEMENTATION DEFINED classification of External aborts. For any abort other than an External abort this bit returns a value of 0. U CM 8 8 Cache maintenance. Indicates whether the Data Abort came from a cache maintenance or address translation instruction: 0b0 The Data Abort was not generated by the execution of one of the System instructions identified in the description of value 1. 0b1 The Data Abort was generated by either the execution of a cache maintenance instruction or by a synchronous fault on the execution of an address translation instruction. The DC ZVA instruction is not classified as a cache maintenance instruction, and therefore its execution cannot cause this field to be set to 1. U S1PTW 7 7 For a stage 2 fault, indicates whether the fault was a stage 2 fault on an access made for a stage 1 translation table walk: 0b0 Fault not on a stage 2 translation for a stage 1 translation table walk. 0b1 Fault on the stage 2 translation of an access for a stage 1 translation table walk. For any abort other than a stage 2 fault this bit is RES0. U WnR 6 6 Write not Read. Indicates whether a synchronous abort was caused by an instruction writing to a memory location, or by an instruction reading from a memory location. The possible values of this bit are: 0b0 Abort caused by an instruction reading from a memory location. 0b1 Abort caused by an instruction writing to a memory location. For faults on cache maintenance and address translation instructions, this bit always returns a value of 1. For faults from an atomic instruction that both reads and writes from a memory location, this bit is set to 0 if a read of the address specified by the instruction would have generated the fault which is being reported, otherwise it is set to 1. The architecture permits, but does not require, a relaxation of this requirement such that for all stage 2 aborts on stage 1 translation table walks for atomic instructions, the WnR bit is always 0. This field is UNKNOWN for: An External abort on an Atomic access. A fault reported using a DFSC value of 0b110101 or 0b110001, indicating an unsupported Exclusive or atomic access. U DFSC 5 0 Data Fault Status Code. Possible values of this field are: 0b000000 Address size fault, level 0 of translation or translation table base register. 0b000001 Address size fault, level 1. 0b000010 Address size fault, level 2. 0b000011 Address size fault, level 3. 0b000100 Translation fault, level 0. 0b000101 Translation fault, level 1. 0b000110 Translation fault, level 2. 0b000111 Translation fault, level 3. 0b001001 Access flag fault, level 1. 0b001010 Access flag fault, level 2. 0b001011 Access flag fault, level 3. 0b001101 Permission fault, level 1. 0b001110 Permission fault, level 2. 0b001111 Permission fault, level 3. 0b010000 Synchronous External abort, not on translation table walk. 0b010001 Synchronous Tag Check fail 0b010100 Synchronous External abort, on translation table walk, level 0. 0b010101 Synchronous External abort, on translation table walk, level 1. 0b010110 Synchronous External abort, on translation table walk, level 2. 0b010111 Synchronous External abort, on translation table walk, level 3. 0b011000 Synchronous parity or ECC error on memory access, not on translation table walk. 0b011100 Synchronous parity or ECC error on memory access on translation table walk, level 0. 0b011101 Synchronous parity or ECC error on memory access on translation table walk, level 1. 0b011110 Synchronous parity or ECC error on memory access on translation table walk, level 2. 0b011111 Synchronous parity or ECC error on memory access on translation table walk, level 3. 0b100001 Alignment fault. 0b110000 TLB conflict abort. 0b110001 Unsupported atomic hardware update fault, if the implementation includes . Otherwise reserved. 0b110100 IMPLEMENTATION DEFINED fault (Lockdown). 0b110101 IMPLEMENTATION DEFINED fault (Unsupported Exclusive or Atomic access). 0b111101 Section Domain Fault, used only for faults reported in the PAR_EL1. 0b111110 Page Domain Fault, used only for faults reported in the PAR_EL1. All other values are reserved. When the RAS Extension is implemented, 0b011000, 0b011100, 0b011101, 0b011110, and 0b011111, are reserved. For more information about the lookup level associated with a fault, see . Because Access flag faults and Permission faults can only result from a Block or Page translation table descriptor, they cannot occur at level 0.If the S1PTW bit is set, then the level refers the level of the stage2 translation that is translating a stage 1 translation walk. U Exception from a trapped floating-point exception 0 24 24 Reserved, RES0. TFV 23 23 Trapped Fault Valid bit. Indicates whether the IDF, IXF, UFF, OFF, DZF, and IOF bits hold valid information about trapped floating-point exceptions. The possible values of this bit are: 0b0 The IDF, IXF, UFF, OFF, DZF, and IOF bits do not hold valid information about trapped floating-point exceptions and are UNKNOWN. 0b1 One or more floating-point exceptions occurred during an operation performed while executing the reported instruction. The IDF, IXF, UFF, OFF, DZF, and IOF bits indicate trapped floating-point exceptions that occurred. For more information see . It is IMPLEMENTATION DEFINED whether this field is set to 0 on an exception generated by a trapped floating point exception from a vector instruction. This is not a requirement. Implementations can set this field to 1 on a trapped floating-point exception from a vector instruction and return valid information in the {IDF, IXF, UFF, OFF, DZF, IOF} fields. U 0 22 11 Reserved, RES0. VECITR 10 8 For a trapped floating-point exception from an instruction executed in AArch32 state this field is RES1. For a trapped floating-point exception from an instruction executed in AArch64 state this field is UNKNOWN. U IDF 7 7 Input Denormal floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Input denormal floating-point exception has not occurred. 0b1 Input denormal floating-point exception occurred during execution of the reported instruction. U 0 6 5 Reserved, RES0. IXF 4 4 Inexact floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Inexact floating-point exception has not occurred. 0b1 Inexact floating-point exception occurred during execution of the reported instruction. U UFF 3 3 Underflow floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Underflow floating-point exception has not occurred. 0b1 Underflow floating-point exception occurred during execution of the reported instruction. U OFF 2 2 Overflow floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Overflow floating-point exception has not occurred. 0b1 Overflow floating-point exception occurred during execution of the reported instruction. U DZF 1 1 Divide by Zero floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Divide by Zero floating-point exception has not occurred. 0b1 Divide by Zero floating-point exception occurred during execution of the reported instruction. U IOF 0 0 Invalid Operation floating-point exception trapped bit. If the TFV field is 0, this bit is UNKNOWN. Otherwise, the possible values of this bit are: 0b0 Invalid Operation floating-point exception has not occurred. 0b1 Invalid Operation floating-point exception occurred during execution of the reported instruction. U In an implementation that supports the trapping of floating-point exceptions: From an Exception level using AArch64, the FPCR.{IDE, IXE, UFE, OFE, DZE, IOE} bits enable each of the floating-point exception traps. From an Exception level using AArch32, the FPSCR.{IDE, IXE, UFE, OFE, DZE, IOE} bits enable each of the floating-point exception traps. SError interrupt IDS 24 24 IMPLEMENTATION DEFINED syndrome. Possible values of this bit are: 0b0 Bits[23:0] of the ISS field holds the fields described in this encoding. If the RAS Extension is not implemented, this means that bits[23:0] of the ISS field are RES0. 0b1 Bits[23:0] of the ISS field holds IMPLEMENTATION DEFINED syndrome information that can be used to provide additional information about the SError interrupt. This field was previously called ISV. U 0 23 14 Reserved, RES0. IESB 13 13 Implicit error synchronization event. 0b0 The SError interrupt was either not synchronized by the implicit error synchronization event or not taken immediately. 0b1 The SError interrupt was synchronized by the implicit error synchronization event and taken immediately. This field is RES0 if the value returned in the DFSC field is not 0b010001. Armv8.2 requires the implementation of the RAS Extension and . U When ARMv8.2-IESB is implemented 0 13 13 Reserved, RES0. AET 12 10 Asynchronous Error Type. When the RAS Extension is implemented and DFSC is 0b010001, describes the state of the PE after taking the SError interrupt exception. The possible values of this field are: 0b000 Uncontainable error (UC). 0b001 Unrecoverable error (UEU). 0b010 Restartable error (UEO). 0b011 Recoverable error (UER). 0b110 Corrected error (CE). All other values are reserved. If multiple errors are taken as a single SError interrupt exception, the overall state of the PE is reported. For example, if both a Recoverable and Unrecoverable error occurred, the state is Unrecoverable. Software can use this information to determine what recovery might be possible. The recovery software must also examine any implemented fault records to determine the location and extent of the error.This field is RES0 if either: The RAS Extension is not implemented. The value returned in the DFSC field is not 0b010001. Armv8.2 requires the implementation of the RAS Extension. U EA 9 9 External abort type. When the RAS Extension is implemented, this bit can provide an IMPLEMENTATION DEFINED classification of External aborts. For any abort other than an External abort this bit returns a value of 0. This field is RES0 if either: The RAS Extension is not implemented. The value returned in the DFSC field is not 0b010001. Armv8.2 requires the implementation of the RAS Extension. U 0 8 6 Reserved, RES0. DFSC 5 0 Data Fault Status Code. When the RAS Extension is implemented, possible values of this field are: 0b000000 Uncategorized. 0b010001 Asynchronous SError interrupt. All other values are reserved. If the RAS Extension is not implemented, this field is RES0. Armv8.2 requires the implementation of the RAS Extension. U Exception from a Breakpoint or Vector Catch debug exception 0 24 6 Reserved, RES0. IFSC 5 0 Instruction Fault Status Code. This field is set to 0b100010, to indicate a Debug exception. U For more information about generating these exceptions: For exceptions from AArch64, see . For exceptions from AArch32, see and . Exception from a Software Step exception ISV 24 24 Instruction syndrome valid. Indicates whether the EX bit, ISS[6], is valid, as follows: 0b0 EX bit is RES0. 0b1 EX bit is valid. See the EX bit description for more information. U 0 23 7 Reserved, RES0. EX 6 6 Exclusive operation. If the ISV bit is set to 1, this bit indicates whether a Load-Exclusive instruction was stepped. 0b0 An instruction other than a Load-Exclusive instruction was stepped. 0b1 A Load-Exclusive instruction was stepped. If the ISV bit is set to 0, this bit is RES0, indicating no syndrome data is available. U IFSC 5 0 Instruction Fault Status Code. This field is set to 0b100010, to indicate a Debug exception. U For more information about generating these exceptions, see . Exception from a Watchpoint exception 0 24 14 Reserved, RES0. VNCR 13 13 Indicates that the watchpoint came from use of VNCR_EL2 register by EL1 code. 0b0 The watchpoint was not generated by the use of VNCR_EL2 by EL1 code. 0b1 The watchpoint was generated by the use of VNCR_EL2 by EL1 code. This field is 0 in ESR_EL1. U When ARMv8.4-NV is implemented 0 13 13 Reserved, RES0. 0 12 9 Reserved, RES0. CM 8 8 Cache maintenance. Indicates whether the Watchpoint exception came from a cache maintenance or address translation instruction: 0b0 The Watchpoint exception was not generated by the execution of one of the System instructions identified in the description of value 1. 0b1 The Watchpoint exception was generated by either the execution of a cache maintenance instruction or by a synchronous Watchpoint exception on the execution of an address translation instruction. The DC ZVA instruction is not classified as a cache maintenance instruction, and therefore its execution cannot cause this field to be set to 1. U 0 7 7 Reserved, RES0. WnR 6 6 Write not Read. Indicates whether the Watchpoint exception was caused by an instruction writing to a memory location, or by an instruction reading from a memory location. The possible values of this bit are: 0b0 Watchpoint exception caused by an instruction reading from a memory location. 0b1 Watchpoint exception caused by an instruction writing to a memory location. For Watchpoint exceptions on cache maintenance and address translation instructions, this bit always returns a value of 1. For Watchpoint exceptions from an atomic instruction, this field is set to 0 if a read of the location would have generated the Watchpoint exception, otherwise it is set to 1. If multiple watchpoints match on the same access, it is UNPREDICTABLE which watchpoint generates the Watchpoint exception. U DFSC 5 0 Data Fault Status Code. This field is set to 0b100010, to indicate a Debug exception. U For more information about generating these exceptions, see . Exception from execution of a Breakpoint instruction 0 24 16 Reserved, RES0. Comment 15 0 Set to the instruction comment field value, zero extended as necessary. For the AArch32 BKPT instructions, the comment field is described as the immediate field. U For more information about generating these exceptions, see . When ARMv8.3-NV is implemented Exception from ERET, ERETAA or ERETAB instruction This EC value only applies when HCR_EL2.NV is 1. 0 24 2 Reserved, RES0. ERET 1 1 Indicates whether an ERET or ERETA* instruction was trapped to EL2. Possible values are: 0b0 ERET instruction trapped to EL2. 0b1 ERETAA or ERETAB instruction trapped to EL2. If this bit is 0, the ERETA field is RES0. U ERETA 0 0 Indicates whether an ERETAA or ERETAB instruction was trapped to EL2. Possible values are: 0b0 ERETAA instruction trapped to EL2. 0b1 ERETAB instruction trapped to EL2. When the ERET field is 0, this bit is RES0. U For more information about generating these exceptions, see . When ARMv8.3-NV is implemented When ARMv8.5-BTI is implemented Exception from Branch Target Identification instruction 0 24 2 Reserved, RES0. BTYPE 1 0 This field is set to the PSTATE.BTYPE value that generated the Branch Target Exception. For more information about generating these exceptions, see . When ARMv8.5-BTI is implemented Exception from a Pointer Authentication instruction when HCR_EL2.API == 0 || SCR_EL3.API == 0 0 24 0 Reserved, RES0. For more information about generating these exceptions, see: . . When HCR_EL2.E2H is 1, without explicit synchronization, access from EL3 using the mnemonic ESR_EL1 or ESR_EL12 are not guaranteed to be ordered with respect to accesses using the other mnemonic. MRS <Xt>, ESR_EL1 if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TRVM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '111' then return NVMem[0x138]; else return ESR_EL1; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then return ESR_EL2; else return ESR_EL1; elsif PSTATE.EL == EL3 then return ESR_EL1; MSR ESR_EL1, <Xt> if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TVM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '111' then NVMem[0x138] = X[t]; else ESR_EL1 = X[t]; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then ESR_EL2 = X[t]; else ESR_EL1 = X[t]; elsif PSTATE.EL == EL3 then ESR_EL1 = X[t]; MRS <Xt>, ESR_EL12 if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '101' then return NVMem[0x138]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if EL2Enabled() && HCR_EL2.E2H == '1' then return ESR_EL1; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && HCR_EL2.E2H == '1' then return ESR_EL1; else UNDEFINED; MSR ESR_EL12, <Xt> if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '101' then NVMem[0x138] = X[t]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if EL2Enabled() && HCR_EL2.E2H == '1' then ESR_EL1 = X[t]; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && HCR_EL2.E2H == '1' then ESR_EL1 = X[t]; else UNDEFINED; MRS <Xt>, ESR_EL2 if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV> == '11' then return ESR_EL1; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then return ESR_EL2; elsif PSTATE.EL == EL3 then return ESR_EL2; MSR ESR_EL2, <Xt> if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV> == '11' then ESR_EL1 = X[t]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then ESR_EL2 = X[t]; elsif PSTATE.EL == EL3 then ESR_EL2 = X[t]; 27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376