TPIDR_EL2, EL2 Software Thread ID Register

The TPIDR_EL2 characteristics are:

Purpose

Provides a location where software executing at EL2 can store thread identifying information, for OS management purposes.

The PE makes no use of this register.

This register is part of:

Configuration

AArch64 System register TPIDR_EL2 bits [31:0] are architecturally mapped to AArch32 System register HTPIDR.

If EL2 is not implemented, this register is RES0 from EL3.

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

TPIDR_EL2 is a 64-bit register.

Field descriptions

The TPIDR_EL2 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
Thread ID
Thread ID
313029282726252423222120191817161514131211109876543210

Bits [63:0]

Thread ID. Thread identifying information stored by software running at this Exception level.

Accessing the TPIDR_EL2

This register can be read using MRS with the following syntax:

MRS <Xt>, <systemreg>

This register can be written using MSR (register) with the following syntax:

MSR <systemreg>, <Xt>

This syntax uses the following encoding in the System instruction encoding space:

<systemreg> op0op1CRnCRmop2
TPIDR_EL21110011010000010

Accessibility

The register is accessible as follows:

Control Accessibility
E2HTGENSEL0EL1EL2EL3
xx0 - - n/a RW
x01 - - RWRW
x11 - n/a RWRW

This table applies to all instructions that can access this register.




18/04/2017 17:00

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