DBGWFAR, Debug Watchpoint Fault Address Register

The DBGWFAR characteristics are:

Purpose

Previously returned information about the address of the instruction that accessed a watchpointed address. Is now deprecated and RES0.

Configuration

This register is present only when AArch32 is supported at any Exception level. Otherwise, direct accesses to DBGWFAR are UNDEFINED.

Attributes

DBGWFAR is a 32-bit register.

Field descriptions

The DBGWFAR bit assignments are:

313029282726252423222120191817161514131211109876543210
RES0

Bits [31:0]

Reserved, RES0.

Accessing the DBGWFAR

Accesses to this register use the following encodings:

MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

coprocopc1CRnCRmopc2
0b11100b0000b00000b01100b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDA> != '00' then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.<TDE,TDA> != '00' then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else return DBGWFAR; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else return DBGWFAR; elsif PSTATE.EL == EL3 then return DBGWFAR;

MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

coprocopc1CRnCRmopc2
0b11100b0000b00000b01100b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDA> != '00' then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.<TDE,TDA> != '00' then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else DBGWFAR = R[t]; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x05); else DBGWFAR = R[t]; elsif PSTATE.EL == EL3 then DBGWFAR = R[t];


30/03/2021 20:51; e3551d56dc294a4d55296a6c10544191ada08a8e

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