AMCNTENCLR0

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AMCNTENCLR0, Activity Monitors Count Enable Clear Register 0

Purpose

Disable control bits for the architected activity monitors event counters, AMEVCNTR0<n>.

Configuration

External register AMCNTENCLR0 bits [31:0] are architecturally mapped to AArch64 System register AMCNTENCLR0_EL0[31:0].

External register AMCNTENCLR0 bits [31:0] are architecturally mapped to AArch64 System register AMCNTENSET0_EL0[31:0].

External register AMCNTENCLR0 bits [31:0] are architecturally mapped to AArch32 System register AMCNTENCLR0[31:0].

External register AMCNTENCLR0 bits [31:0] are architecturally mapped to AArch32 System register AMCNTENSET0[31:0].

External register AMCNTENCLR0 bits [31:0] are architecturally mapped to External register AMCNTENSET0[31:0].

It is IMPLEMENTATION DEFINED whether AMCNTENCLR0 is implemented in the Core power domain or in the Debug power domain.

This register is present only when FEAT_AMUv1 is implemented and FEAT_AMU_EXT32 is implemented. Otherwise, direct accesses to AMCNTENCLR0 are RES0.

Attributes

Field descriptions

Bits [31:16]

Bits [15:4]

Reserved, RAZ/WI.

This field is reserved for additional architected activity monitor event counters, which Arm might define in a future version of the Activity Monitors architecture.

P<n>, bit [n], for n = 3 to 0

Activity monitor event counter disable bit for AMEVCNTR0<n>.

Note

AMCGCR.CG0NC identifies the number of architected activity monitor event counters. In an implementation that includes FEAT_AMUv1, the number of architected activity monitor event counters is 4.

Possible values of each bit are:

P<n>	Meaning
0b0	When read, means that AMEVCNTR0<n> is disabled.
0b1	When read, means that AMEVCNTR0<n> is enabled.

The reset behavior of this field is:

On an AMU reset, this field resets to '0'.

Accessing this field has the following behavior:

When n >= 4, access to this field is RAZ/WI.
Otherwise, access to this field is W1C.

Accessing AMCNTENCLR0

Accesses to this register use the following encodings:

Accessible at offset 0xC20 from AMU

When FEAT_RME is implemented, FEAT_AMU_EXTACR is implemented, an access is Secure, and AMROOTCR().RA IN {0b001, 0b000}, accesses to this register are RAZ/WI.
When FEAT_RME is implemented, FEAT_AMU_EXTACR is implemented, an access is Realm, and AMROOTCR().RA IN {0b010, 0b000}, accesses to this register are RAZ/WI.
When FEAT_RME is implemented, FEAT_AMU_EXTACR is implemented, an access is Non-secure, and AMROOTCR().RA != 0b011, accesses to this register are RAZ/WI.
When FEAT_RME is not implemented, FEAT_AMU_EXTACR is implemented, an access is Non-secure, and AMSCR().NSRA == 0, accesses to this register are RAZ/WI.
Otherwise, accesses to this register are RO.

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
RES0																RAZ/WI												P3	P2	P1	P0