OSDTRTX_EL1, OS Lock Data Transfer Register, Transmit

The OSDTRTX_EL1 characteristics are:

Purpose

Used for save/restore of DBGDTRTX_EL0. It is a component of the Debug Communications Channel.

Configuration

AArch64 System register OSDTRTX_EL1 bits [31:0] are architecturally mapped to AArch32 System register DBGDTRTXext[31:0].

Attributes

OSDTRTX_EL1 is a 64-bit register.

Field descriptions

The OSDTRTX_EL1 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
Return DTRTX without side-effect

Bits [63:32]

Reserved, RES0.

Bits [31:0]

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'.

Accessing the OSDTRTX_EL1

Arm deprecates reads and writes of OSDTRTX_EL1 when the OS Lock is unlocked.

Accesses to this register use the following encodings:

MRS <Xt>, OSDTRTX_EL1

op0op1CRnCRmop2
0b100b0000b00000b00110b010

if PSTATE.EL == EL0 then UNDEFINED; elsif Halted() && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then return OSDTRTX_EL1; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDCC == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && MDCR_EL2.TDCC == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.<TDE,TDA> != '00' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDCC == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return OSDTRTX_EL1; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDCC == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TDCC == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return OSDTRTX_EL1; elsif PSTATE.EL == EL3 then return OSDTRTX_EL1;

MSR OSDTRTX_EL1, <Xt>

op0op1CRnCRmop2
0b100b0000b00000b00110b010

if PSTATE.EL == EL0 then UNDEFINED; elsif Halted() && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then OSDTRTX_EL1 = X[t]; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDCC == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && MDCR_EL2.TDCC == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.<TDE,TDA> != '00' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDCC == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else OSDTRTX_EL1 = X[t]; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDCC == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TDCC == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else OSDTRTX_EL1 = X[t]; elsif PSTATE.EL == EL3 then OSDTRTX_EL1 = X[t];


30/03/2021 20:51; e3551d56dc294a4d55296a6c10544191ada08a8e

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