ARM Cortex-A53 MPCore

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Debug

ID021414 Non-Confidential

[20] WT Watchpoint Type. This bit is set to 1 to link the watchpoint to a breakpoint to create a linked watchpoint that

requires both data address matching and Context matching:

Unlinked data address match.

Linked data address match.

When this bit is set to 1 the linked BRP number field indicates the BRP that this WRP is linked. See the ARM

Architecture Reference Manual ARMv8, for ARMv8-A architecture profile for more information.

[19:16] LBN Linked Breakpoint Number. If this watchpoint is programmed with the watchpoint type set to linked, then this

field must be programmed with the number of the breakpoint that defines the Context match to be combined with

data address comparison. Otherwise, this field must be programmed to

b0000

Reading this register returns an

UNKNOWN value for this field, and the generation of Watchpoint debug events is

UNPREDICTABLE, if either:

• This watchpoint does not have linking enabled and this field is not programmed to

0x0

• This watchpoint has linking enabled and the breakpoint indicated by this field does not support Context

matching, is not programmed for Context matching, or does not exist.

See the ARM

Architecture Reference Manual ARMv8, for ARMv8-A architecture profile for more information.

[15:14] SSC Security State Control. This field enables the watchpoint to be conditional on the security state of the processor.

This field is used with the Hyp Mode Control (HMC) and Privileged Access Control (PAC) fields.

See the ARM

Architecture Reference Manual ARMv8, for ARMv8-A architecture profile for possible values of

the fields, and the access modes and security states that can be tested.

[13] HMC Hyp Mode Control. This field is used with the Security State Control (SSC) and PAC fields. The value of

DBGWCR.PAC has no effect for accesses made in Hyp mode.

See the ARM

Architecture Reference Manual ARMv8, for ARMv8-A architecture profile for possible values of

the fields, and the access modes and security states that can be tested.

[12:5] BAS Byte Address Select. The processor implements an 8-bit Byte address select field, DBGWCR[12:5].

A DBGWVR is programmed with a word-aligned address. This field enables the watchpoint to hit only if certain

bytes of the addressed word are accessed. The watchpoint hits if an access hits any byte being watched, even if:

• The access size is larger than the size of the region being watched.

• The access is unaligned, and the base address of the access is not in the same word of memory as the

address in the DBGWVR.

• The access size is smaller than the size of region being watched.

See the ARM

Architecture Reference Manual ARMv8, for ARMv8-A architecture profile for more information.

Table 11-5 DBGWCRn_EL1 bit assignments (continued)

Bits Name Function

ARM Cortex-A53 MPCore - Page 414