aarch64-cpu-ext

aarch64-cpu-ext

A Rust library providing extended AArch64 CPU utilities and cache management operations.

Overview

This library extends the functionality of the aarch64-cpu crate by providing additional utilities for:

• Cache management operations (invalidate, clean, flush)
• Cache line size detection
• Low-level assembly operations for cache and TLB management
• Register access through re-exported aarch64-cpu registers

Features

• Cache Operations: Comprehensive cache management including clean, invalidate, and flush operations
• Cache Line Size Detection: Runtime detection of cache line sizes using CTR_EL0 register
• Translation Table Entries: Complete TTE64 implementation supporting 4KB/16KB/64KB granules and 48/52-bit addresses
• Assembly Wrappers: Low-level assembly instruction wrappers for cache and TLB operations
• No Standard Library: #![no_std] compatible for embedded and bare-metal environments
• Register Access: Full access to AArch64 system registers through re-exported functionality

Usage

Add this to your Cargo.toml:

[dependencies]
aarch64-cpu-ext = "0.1.0"

Cache Operations

use aarch64_cpu_ext::cache::{icache_flush_all, cache_line_size, dcache_range, CacheOp};

// Flush instruction cache
icache_flush_all();

// Get cache line size
let line_size = cache_line_size();

// Perform cache operations on memory ranges
let buffer = &mut [0u8; 4096];
dcache_range(CacheOp::Clean, buffer.as_ptr() as usize, buffer.len());
dcache_range(CacheOp::Invalidate, buffer.as_ptr() as usize, buffer.len());
dcache_range(CacheOp::CleanAndInvalidate, buffer.as_ptr() as usize, buffer.len());

Register Access

use aarch64_cpu_ext::registers::*;

// Access system registers (re-exported from aarch64-cpu)
let current_el = CurrentEL.get();

Translation Table Entries (TTE64)

use aarch64_cpu_ext::structures::tte::*;

// Create a 4KB granule, 48-bit address table entry
let table_addr = 0x10_0000; // Must be aligned to granule size
let table_tte = TTE4K48::table(table_addr, 1); // attr_index = 1

// Create a block entry with detailed configuration
let block_addr = 0x20_0000;
let config = BlockConfig {
    attr_index: 0,
    access_permissions: access_permissions::RW_EL1,
    shareability: Shareability::InnerShareable,
    executable: false,
    privileged_executable: false,
    contiguous: false,
    not_global: false,
};
let block_tte = TTE4K48::new_block(block_addr, config);

// Different granule sizes and address widths
let tte_16k_48 = TTE16K48::table(0x4000, 0);   // 16KB granule, 48-bit
let tte_64k_52 = TTE64K52::table(0x10000, 2);  // 64KB granule, 52-bit

// Address alignment utilities
let aligned_addr = TTE4K48::align_up(0x12345);
let is_aligned = TTE64K48::is_aligned(0x10000);

// Virtual address index calculation for page table walks
let va = 0x1234_5678_9ABC_DEF0;
let level0_index = TTE4K48::calculate_index(va, 0);

Supported Configurations

Granule	Address Width	Type Alias
4KB	48-bit	TTE4K48
4KB	52-bit	TTE4K52
16KB	48-bit	TTE16K48
16KB	52-bit	TTE16K52
64KB	48-bit	TTE64K48
64KB	52-bit	TTE64K52

Low-level Assembly Operations

use aarch64_cpu_ext::asm::cache::{dc, ic, CVAC, IALLU};

// Direct assembly instruction wrappers
ic(IALLU);  // Instruction cache invalidate all
dc(CVAC, address);  // Data cache clean by virtual address

Cache Operation Types

• Clean: Write dirty cache lines back to memory without invalidating
• Invalidate: Mark cache lines as invalid without writing back
• CleanAndInvalidate: Write back dirty lines and mark as invalid

Requirements

• AArch64 target architecture
• Rust 2024 edition
• No standard library (#![no_std])

Dependencies

• aarch64-cpu version 10 - Provides base AArch64 CPU functionality
• tock-registers version 0.9 - Register access and manipulation utilities

Target Architecture

This library is specifically designed for AArch64 (ARM64) architecture and will not compile for other targets.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contributing

Contributions are welcome! Please ensure that any new features maintain compatibility with #![no_std] environments and follow the existing code patterns.