See the Arm
®
Architecture Reference Manual Armv8, for Armv8-A architecture profile for more
information on how the BAS field is interpreted by hardware.
[4:3]
Reserved, RES0.
PMC, [2:1]
Privileged Mode Control. Determines the exception level or levels that a breakpoint debug event
for breakpoint n is generated.
This field must be interpreted with the SSC and HMC fields to determine the mode and security
states that can be tested.
See the Arm
®
Architecture Reference Manual Armv8, for Armv8-A architecture profile for
possible values of the fields.
Bits[2:1] have no effect for accesses made in Hyp mode.
E, [0]
Enable breakpoint. This bit enables the BRP:
0 BRP disabled.
1 BRP enabled.
A BRP never generates a breakpoint debug event when it is disabled.
The value of DBGBCRn.E is UNKNOWN on reset. A debugger must ensure that DBGBCRn.E has
a defined value before it enables debug.
To access the DBGBCRn:
MRC p14, 0, <Rt>, c0, cn, 4; Read Debug Breakpoint Control Register nMCR p14, 0, <Rt>, c0,
cn, 4; Write Debug Breakpoint Control Register n
The DBGBCRn_EL1 can be accessed through the external debug interface, offset 0x4n8. The range of
bits for DBGBCRn_EL1 is 0 to 5.
C6 AArch32 debug registers
C6.2 Debug Breakpoint Control Registers
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