PMMIR, Performance Monitors Machine Identification Register

Reserved, RES0.

PMU event edge detection. With PMMIR.THWIDTH, indicates implementation of event counter thresholding features.

The value of this field is an IMPLEMENTATION DEFINED choice of:

EDGE	Meaning
0b0000	FEAT_PMUv3_EDGE is not implemented.
0b0001	FEAT_PMUv3_EDGE is implemented.

All other values are reserved.

If FEAT_PMUv3_TH is not implemented, the only permitted value is 0b0000.

FEAT_PMUv3_EDGE implements the functionality identified by the value 0b0001.

Access to this field is RO.

PMEVTYPER<n>_EL0.TH width. Indicates implementation of the FEAT_PMUv3_TH feature, and, if implemented, the size of the PMEVTYPER<n>_EL0.TH field.

The value of this field is an IMPLEMENTATION DEFINED choice of:

THWIDTH	Meaning
0b0000	FEAT_PMUv3_TH is not implemented.
0b0001	1 bit. PMEVTYPER<n>_EL0.TH[11:1] are RES0.
0b0010	2 bits. PMEVTYPER<n>_EL0.TH[11:2] are RES0.
0b0011	3 bits. PMEVTYPER<n>_EL0.TH[11:3] are RES0.
0b0100	4 bits. PMEVTYPER<n>_EL0.TH[11:4] are RES0.
0b0101	5 bits. PMEVTYPER<n>_EL0.TH[11:5] are RES0.
0b0110	6 bits. PMEVTYPER<n>_EL0.TH[11:6] are RES0.
0b0111	7 bits. PMEVTYPER<n>_EL0.TH[11:7] are RES0.
0b1000	8 bits. PMEVTYPER<n>_EL0.TH[11:8] are RES0.
0b1001	9 bits. PMEVTYPER<n>_EL0.TH[11:9] are RES0.
0b1010	10 bits. PMEVTYPER<n>_EL0.TH[11:10] are RES0.
0b1011	11 bits. PMEVTYPER<n>_EL0.TH[11] is RES0.
0b1100	12 bits.

All other values are reserved.

If FEAT_PMUv3_TH is not implemented, this field is zero.

Otherwise, the largest value that can be written to PMEVTYPER<n>_EL0.TH is 2^{(PMMIR.THWIDTH)} minus one.

Access to this field is RO.

Bus width. Indicates the number of bytes each BUS_ACCESS event relates to. Encoded as Log₂(number of bytes), plus one.

The value of this field is an IMPLEMENTATION DEFINED choice of:

BUS_WIDTH	Meaning
0b0000	The information is not available.
0b0011	Four bytes.
0b0100	8 bytes.
0b0101	16 bytes.
0b0110	32 bytes.
0b0111	64 bytes.
0b1000	128 bytes.
0b1001	256 bytes.
0b1010	512 bytes.
0b1011	1024 bytes.
0b1100	2048 bytes.

All other values are reserved.

Each transfer is up to this number of bytes. An access might be smaller than the bus width.

When this field is nonzero, each access counted by BUS_ACCESS is at most BUS_WIDTH bytes. An implementation might treat a wide bus as multiple narrower buses, such that a wide access on the bus increments the BUS_ACCESS counter by more than one.

Access to this field is RO.

Bus count. The largest value by which the BUS_ACCESS event might increment in a single BUS_CYCLES cycle.

When this field is nonzero, the largest value by which the BUS_ACCESS event might increment in a single BUS_CYCLES cycle is BUS_SLOTS.

If the bus count information is not available, this field will read as zero.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Operation width. The largest value by which the STALL_SLOT event might increment by in a single cycle. If the STALL_SLOT event is not implemented, this field might read as zero.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.