PMCCIDSR CONTEXTIDR_ELx Sample Register PMU when FEAT_PMUv3_EXT64 is implemented and FEAT_PCSRv8p2 is implemented PMU 0x228 When DoubleLockStatus() or !IsCorePowered() ERROR When (FEAT_PMUv3_EXTPMN is not implemented, or !IsMostSecureAccess(addrdesc), or PMCCR().OSLO == '0') and OSLockStatus() ERROR RO PMVCIDSR Architectural External 31 0 31 0 31 0 31 0 PC Sample-based Profiling Extension register that contains the sampled value of CONTEXTIDR_EL1 and CONTEXTIDR_EL2, captured on reading PMPCSR. PMU PMCCIDSR is a 64-bit register. CONTEXTIDR_EL2 63 32 63:32 Context ID. The value of CONTEXTIDR_EL2 that is associated with the most recent PMPCSR sample. When the most recent PMPCSR sample is generated: If the PE is not executing at EL3, EL2 is using AArch64, and EL2 is enabled in the current Security state, then this field is set to the Context ID sampled from CONTEXTIDR_EL2. Otherwise, this field is set to an UNKNOWN value. Because the value written to this field is an indirect read of CONTEXTIDR_EL2, it is CONSTRAINED UNPREDICTABLE whether this field is set to the original or new value if PMPCSR samples: An instruction that writes to CONTEXTIDR_EL2. The next Context synchronization event. Any instruction executed between these two instructions. AU CONTEXTIDR_EL1 31 0 31:0 Context ID. The value of CONTEXTIDR that is associated with the most recent PMPCSR sample. When the most recent PMPCSR sample is generated: If EL1 is using AArch64, then the Context ID is sampled from CONTEXTIDR_EL1. If EL1 is using AArch32, then the Context ID is sampled from CONTEXTIDR. If EL3 is implemented and is using AArch32, then CONTEXTIDR is a banked register and this register samples the current banked copy of CONTEXTIDR for the Security state that is associated with the most recent PMPCSR sample. Because the value written to this register is an indirect read of CONTEXTIDR, it is CONSTRAINED UNPREDICTABLE whether this register is set to the original or new value if PMPCSR samples: An instruction that writes to CONTEXTIDR. The next Context synchronization event. Any instruction executed between these two instructions. AU If FEAT_PCSRv8p2 and FEAT_PMUv3_EXT32 are implemented, then the same content is present in the same locations, and can be accessed using PMCID2SR[31:0] and PMCID1SR[31:0]. IMPLEMENTATION DEFINED extensions to external debug might make the value of this register UNKNOWN, see 'Permitted behavior that might make the PC Sample-based profiling registers UNKNOWN'. Accessible at offset 0x228 from PMU 2026-03-26 20:27:25 2026-03_rel