Hyp Software Thread ID Register
Provides a location where software running in Hyp mode can store thread identifying information that is not visible to Non-secure software executing at EL0 or EL1, for hypervisor management purposes.
The PE makes no use of this register.
AArch32 System register HTPIDR bits [31:0] are architecturally mapped to AArch64 System register TPIDR_EL2[31:0].
This register is present only when FEAT_AA32EL2 is implemented. Otherwise, direct accesses to HTPIDR are UNDEFINED.
If EL2 is not implemented, this register is RES0 from EL3.
The PE never updates this register.
HTPIDR 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 |
| TID | |||||||||||||||||||||||||||||||
Thread ID. Thread identifying information stored by software running at this Exception level.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b100, CRn = 0b1101, CRm = 0b0000, opc2 = 0b010)
if !IsFeatureImplemented(FEAT_AA32EL2) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T13 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T13 == '1' then AArch32.TakeHypTrapException(0x03); else UNDEFINED; elsif PSTATE.EL == EL2 then R[t] = HTPIDR; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else R[t] = HTPIDR;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b100, CRn = 0b1101, CRm = 0b0000, opc2 = 0b010)
if !IsFeatureImplemented(FEAT_AA32EL2) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T13 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T13 == '1' then AArch32.TakeHypTrapException(0x03); else UNDEFINED; elsif PSTATE.EL == EL2 then HTPIDR = R[t]; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else HTPIDR = R[t];
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