The PMCCFILTR_EL0 characteristics are:
Determines the modes in which the Cycle Counter, PMCCNTR_EL0, increments.
External register PMCCFILTR_EL0 bits [31:0] are architecturally mapped to AArch64 System register PMCCFILTR_EL0[31:0] .
External register PMCCFILTR_EL0 bits [31:0] are architecturally mapped to AArch32 System register PMCCFILTR[31:0] .
PMCCFILTR_EL0 is in the Core power domain.
On a Warm or Cold reset RW fields in this register reset:
To architecturally UNKNOWN values if the reset is to an Exception level that is using AArch64.
To 0 if the reset is to an Exception level that is using AArch32.
The register is not affected by an External debug reset.
PMCCFILTR_EL0 is a 32-bit register.
The PMCCFILTR_EL0 bit assignments are:
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 |
P | U | NSK | NSU | NSH | M | 0 | SH | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Privileged filtering bit. Controls counting in EL1. If EL3 is implemented, then counting in Non-secure EL1 is further controlled by the PMCCFILTR_EL0.NSK bit. The possible values of this bit are:
P | Meaning |
---|---|
0b0 |
Count cycles in EL1. |
0b1 |
Do not count cycles in EL1. |
User filtering bit. Controls counting in EL0. If EL3 is implemented, then counting in Non-secure EL0 is further controlled by the PMCCFILTR_EL0.NSU bit. The possible values of this bit are:
U | Meaning |
---|---|
0b0 |
Count cycles in EL0. |
0b1 |
Do not count cycles in EL0. |
Non-secure EL1 (kernel) modes filtering bit. Controls counting in Non-secure EL1. If EL3 is not implemented, this bit is RES0.
If the value of this bit is equal to the value of the PMCCFILTR_EL0.P bit, cycles in Non-secure EL1 are counted.
Otherwise, cycles in Non-secure EL1 are not counted.
Non-secure EL0 (Unprivileged) filtering bit. Controls counting in Non-secure EL0. If EL3 is not implemented, this bit is RES0.
If the value of this bit is equal to the value of the PMCCFILTR_EL0.U bit, cycles in Non-secure EL0 are counted.
Otherwise, cycles in Non-secure EL0 are not counted.
EL2 (Hypervisor) filtering bit. Controls counting in EL2. If EL2 is not implemented, this bit is RES0. If Secure EL2 is implemented, counting in Secure EL2 is further controlled by the PMCCFILTR_EL0.SH bit.
NSH | Meaning |
---|---|
0b0 |
Do not count cycles in EL2. |
0b1 |
Count cycles in EL2. |
Secure EL3 filtering bit. If EL3 is not implemented, this bit is RES0.
If the value of this bit is equal to the value of the PMCCFILTR_EL0.P bit, cycles in Secure EL3 are counted.
Otherwise, cycles in Secure EL3 are not counted.
Most applications can ignore this field and set its value to 0.
This field is not visible in the AArch32 PMCCFILTR System register.
Reserved, RES0.
Secure EL2 filtering.
If the value of this bit is not equal to the value of the PMCCFILTR_EL0.NSH bit, cycles in Secure EL2 are counted.
Otherwise, cycles in Secure EL2 are not counted.
If Secure EL2 is not implemented or is disabled, this field is RES0.
This field is not visible in the AArch32 PMCCFILTR System register.
Reserved, RES0.
Reserved, RES0.
SoftwareLockStatus() depends on the type of access attempted and AllowExternalPMUAccess() has a new definition from Armv8.4. Refer to the Pseudocode definitions for more information.
Component | Offset | Instance |
---|---|---|
PMU | 0x47C | PMCCFILTR_EL0 |
This interface is accessible as follows:
13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009
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