System Control Coprocessor
ARM DDI 0363E Copyright ©2009 ARM Limited. All rights reserved. 4-62
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4.2.28 Validation Registers
The processor implements a set of validation registers. This section describes:
•c15, nVAL IRQ Enable Set Register
•c15, nVAL FIQ Enable Set Register on page4-63
•c15, nVAL Reset Enable Set Register on page4-64
•c15, nVAL Debug Request Enable Set Register on page4-64
•c15, nVAL IRQ Enable Clear Register on page4-65
•c15, nVAL FIQ Enable Clear Register on page4-66
•c15, nVAL Reset Enable Clear Register on page 4-67
•c15, nVAL Debug Request Enable Clear Register on page4-68
•c15, nVAL Cache Size Override Register on page4-69.
c15, nVAL IRQ Enable Set Register
The nVAL IRQ Enable Set Register enables any of the PMC Registers, PMC0-PMC2, and
CCNT, to generate an interrupt request on overflow. If enabled, the interrupt request is signaled
by nVALIRQ being asserted LOW.
The nVAL IRQ Enable Set Register is:
• A read/write register.
• Always accessible in Privileged mode. The USEREN Register determines access, see c9,
User Enable Register on page 6-15.
Figure 4-44 shows the bit arrangement for the nVAL IRQ Enable Set Register.
Figure4-44 nVAL IRQ Enable Set Register format
Table4-42 shows how the bit values correspond with the nVAL IRQ Enable Set Register.
To access the nVAL IRQ Enable Set Register, read or write CP15 with:
MRC p15, 0, <Rd>, c15, c1, 0 ; Read nVAL IRQ Enable Set Register
MCR p15, 0, <Rd>, c15, c1, 0 ; Write nVAL IRQ Enable Set Register
C
31 3210
Reserved
P2
P1
P0
Performance monitor counter
overflow IRQ request enables
Cycle count overflow IRQ request enable
Table4-42 nVAL IRQ Enable Set Register bit functions
Bits Field Function
[31] C CCNT overflow IRQ request
[30: 3] Reserved UNP or SBZP
[2] P2 PMC2 overflow IRQ request
[1] P1 PMC1 overflow IRQ request
[0] P0 PMC0 overflow IRQ request