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PMMIR: Performance Monitors Machine Identification Register

Purpose

Describes Performance Monitors parameters specific to the implementation.

Configuration

This register is present only when FEAT_PMUv3_EXT is implemented and FEAT_PMUv3p4 is implemented. Otherwise, direct accesses to PMMIR are RES0.

PMMIR is in the Core power domain.

Attributes

PMMIR is a:

This register is part of the PMU block.

Field descriptions

When FEAT_PMUv3_EXT64 is implemented:

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0EDGETHWIDTHBUS_WIDTHBUS_SLOTSSLOTS

Bits [63:28]

Reserved, RES0.

EDGE, bits [27:24]

PMU event edge detection. With PMMIR_EL1.THWIDTH, indicates implementation of event counter thresholding features.

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

EDGEMeaning
0b0000

FEAT_PMUv3_EDGE is not implemented.

0b0001

FEAT_PMUv3_EDGE is implemented.

0b0010

As 0b0001, and adds support for threshold value linking across counters.

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.

FEAT_PMUv3_TH2 implements the functionality identified by the value 0b0010.

Access to this field is RO.

THWIDTH, bits [23:20]

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

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

THWIDTHMeaning
0b0000

FEAT_PMUv3_TH is not implemented.

0b0001

1 bit. PMU.PMEVTYPER<n>_EL0.TH[11:1] are RES0.

0b0010

2 bits. PMU.PMEVTYPER<n>_EL0.TH[11:2] are RES0.

0b0011

3 bits. PMU.PMEVTYPER<n>_EL0.TH[11:3] are RES0.

0b0100

4 bits. PMU.PMEVTYPER<n>_EL0.TH[11:4] are RES0.

0b0101

5 bits. PMU.PMEVTYPER<n>_EL0.TH[11:5] are RES0.

0b0110

6 bits. PMU.PMEVTYPER<n>_EL0.TH[11:6] are RES0.

0b0111

7 bits. PMU.PMEVTYPER<n>_EL0.TH[11:7] are RES0.

0b1000

8 bits. PMU.PMEVTYPER<n>_EL0.TH[11:8] are RES0.

0b1001

9 bits. PMU.PMEVTYPER<n>_EL0.TH[11:9] are RES0.

0b1010

10 bits. PMU.PMEVTYPER<n>_EL0.TH[11:10] are RES0.

0b1011

11 bits. PMU.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 PMU.PMEVTYPER<n>_EL0.TH is 2(PMMIR.THWIDTH) minus one.

Access to this field is RO.

BUS_WIDTH, bits [19:16]

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_WIDTHMeaning
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_SLOTS, bits [15:8]

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.

SLOTS, bits [7:0]

Operation width. The largest value by which the STALL_SLOT event might increment 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.

Otherwise:

313029282726252423222120191817161514131211109876543210
RES0EDGETHWIDTHBUS_WIDTHBUS_SLOTSSLOTS

Bits [31:28]

Reserved, RES0.

EDGE, bits [27:24]

PMU event edge detection. With PMMIR_EL1.THWIDTH, indicates implementation of event counter thresholding features.

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

EDGEMeaning
0b0000

FEAT_PMUv3_EDGE is not implemented.

0b0001

FEAT_PMUv3_EDGE is implemented.

0b0010

As 0b0001, and adds support for threshold value linking across counters.

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.

FEAT_PMUv3_TH2 implements the functionality identified by the value 0b0010.

Access to this field is RO.

THWIDTH, bits [23:20]

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

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

THWIDTHMeaning
0b0000

FEAT_PMUv3_TH is not implemented.

0b0001

1 bit. PMU.PMEVTYPER<n>_EL0.TH[11:1] are RES0.

0b0010

2 bits. PMU.PMEVTYPER<n>_EL0.TH[11:2] are RES0.

0b0011

3 bits. PMU.PMEVTYPER<n>_EL0.TH[11:3] are RES0.

0b0100

4 bits. PMU.PMEVTYPER<n>_EL0.TH[11:4] are RES0.

0b0101

5 bits. PMU.PMEVTYPER<n>_EL0.TH[11:5] are RES0.

0b0110

6 bits. PMU.PMEVTYPER<n>_EL0.TH[11:6] are RES0.

0b0111

7 bits. PMU.PMEVTYPER<n>_EL0.TH[11:7] are RES0.

0b1000

8 bits. PMU.PMEVTYPER<n>_EL0.TH[11:8] are RES0.

0b1001

9 bits. PMU.PMEVTYPER<n>_EL0.TH[11:9] are RES0.

0b1010

10 bits. PMU.PMEVTYPER<n>_EL0.TH[11:10] are RES0.

0b1011

11 bits. PMU.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 PMU.PMEVTYPER<n>_EL0.TH is 2(PMMIR.THWIDTH) minus one.

Access to this field is RO.

BUS_WIDTH, bits [19:16]

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_WIDTHMeaning
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_SLOTS, bits [15:8]

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.

SLOTS, bits [7:0]

Operation width. The largest value by which the STALL_SLOT event might increment 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.

Accessing PMMIR

If the Core power domain is off or in a low-power state, access to this register returns an Error.

Accesses to this register use the following encodings:

When FEAT_PMUv3_EXT64 is implemented or FEAT_PMUv3p9 is implemented

[63:0] Accessible at offset 0xE40 from PMU

When FEAT_PMUv3_EXT32 is implemented and FEAT_PMUv3p9 is not implemented

[31:0] Accessible at offset 0xE40 from PMU