Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 4/01/2024
Public
Document Table of Contents

3.5.3.4.1. Translation Lookaside Buffer

Translation lookaside buffer (TLB) is a cache of recently executed page translations within the MMU. The Cortex-A76 core implements a two-level TLB structure. The TLB stores all page sizes and is responsible for breaking these down into smaller pages when required for the data or instruction L1 TLB.
Table 40.  MMU Components
Component Number of Entries Associativity Description
Instruction L1 TLB 48 Fully associative A hit in the instruction L1 TLB provides a single clock cycle access to the translation and returns the physical address to the instruction cache for comparison. It also checks the access permissions to signal an Instruction Abort.
Data L1 TLB 48 Fully associative A hit in the data L1 TLB provides a single clock cycle access to the translation and returns the physical address to the data cache for comparison. It also checks the access permissions to signal a Data Abort.
L2 TLB 1280 5-way set associative The L2 TLB structure is shared by instruction and data. It handles misses from the instruction and data L1 TLBs.
The TLB entries contain either one or both of a global indicator and an Address Space Identifier (ASID) to permit context switches without requiring the TLB to be invalidated. The TLB entries contain a Virtual Machine Identifier (VMID) to permit virtual machine switches by the hypervisor without requiring the TLB to be invalidated.