ARM r1p3, R4, R4F

Debug

ID013010 Non-Confidential, Unrestricted Access

11.4.14 Watchpoint Value Registers

Each WVR is associated with a Watchpoint Control Register (WCR). WCRy is the

corresponding register for WVRy.

A pair of watchpoint registers, WVRy and WCRy, is called a Watchpoint Register Pair (WRP).

WVR0-7 are paired with WCR0-7 to make WRP0-7.

The watchpoint value contained in the WVR always corresponds to a data address and can be

set either on:

• a data address

• a data address and context ID pair.

For a data address and context ID pair, a WRP and a BRP with context ID comparison capability

must be linked. A debug event is generated when both the data address and the context ID pair

match simultaneously. Table11-19 shows the bit field definitions for the Watchpoint Value

Registers.

11.4.15 Watchpoint Control Registers

The WCRs contain the necessary control bits for setting:

• watchpoints

• linked watchpoints.

Figure 11-11 on page11-27 shows the bit arrangement of the Watchpoint Control Registers.

b011 The corresponding BVR[31:0] is compared against CP15 Context ID Register, c13. This BRP links

another BRP (of the BCR[21:20]=b01 type), or WRP (with WCR[20]=b1). They generate a breakpoint

or watchpoint debug event on a joint instruction address or data address and context ID match. For this

BRP, BCR[8:5] must be set to b1111, BCR[15:14] must be set to b00, and BCR[2:1] must be set to b11.

Otherwise it is Unpredictable whether a breakpoint debug event is generated.

b100 The corresponding BVR[31:2] and BCR[8:5] are compared against the instruction address bus and the

state of the processor against this BCR. It generates a breakpoint debug event on a joint instruction

address mismatch and state match.

b101 The corresponding BVR[31:2] and BCR[8:5] are compared against the instruction address bus and the

state of the processor against this BCR. This BRP is linked with the one indicated by BCR[19:16] linked

BRP field. It generates a breakpoint debug event on a joint instruction address mismatch, state and

context ID match.

b11x Reserved. The behavior is Unpredictable.

Table11-18 Meaning of BVR bits [22:20] (continued)

BVR[22:20] Meaning

Table11-19 Watchpoint Value Registers functions

Bits Description

[31:2] Watchpoint address.

[1:0] Reserved. Do not modify on writes. On reads, the value returns zero.