Debug
ARM DDI 0388I
Copyright © 2008-2012 ARM. All rights reserved.
10-9
ID073015
Non-Confidential
[15:14]
Secure state
access
control
Secure state access control. This field enables the breakpoint to be conditional on the security state of the
processor:
b00
Breakpoint matches in both Secure and Non-secure state.
b01
Breakpoint only matches in Non-secure state.
b10
Breakpoint only matches in Secure state.
b11
Reserved.
[13:9]
-
RAZ on reads, SBZP on writes.
[8:5]
Byte address
select
Byte address select. For breakpoints programmed to match an IVA, you must write a word-aligned address
to the BVR. You can then use this field to program the breakpoint so it hits only if you access certain byte
addresses.
If you program the BRP for IVA match, the breakpoint:
b0000
Never hits.
b0011
Hits if any of the two bytes starting at address BVR &
0xFFFFFFFC
+0 is accessed.
b1100
Hits if any of the two bytes starting at address BVR &
0xFFFFFFFC
+2 is accessed.
b1111
Hits if any of the four bytes starting at address BVR &
0xFFFFFFFC
+0 is accessed.
If you program the BRP for IVA mismatch, the breakpoint hits where the corresponding IVA breakpoint
does not hit, that is, the range of addresses covered by an IVA mismatch breakpoint is the negative image
of the corresponding IVA breakpoint.
If you program the BRP for context ID comparison, this field must be set to b1111. Otherwise, breakpoint
and watchpoint debug events might not be generated as expected.
Note
Writing a value to BCR[8:5] where BCR[8] is not equal to BCR[7], or BCR[6] is not equal to BCR[5], has
UNPREDICTABLE
results.
[4:3]
-
RAZ on reads, SBZP on writes.
[2:1]
SP
Supervisor access control. The breakpoint can be conditioned on the mode of the processor:
b00
User, System, or Supervisor.
b01
Privileged.
b10
User.
b11
Any.
[0]
B
Breakpoint enable:
0
Breakpoint disabled, reset value.
1
Breakpoint enabled.
Table 10-4 BCR Register bit assignments (continued)
Bits
Name
Description