Configuration Hierarchy

LALE uses a 4-layer hierarchical configuration system:

ISA → Core → SoC → Board

Each layer inherits from the previous and can override parameters.
This allows easy board variants with the same SoC but different frequencies.

Layer 1: ISA Configuration

Base instruction set architecture with instruction timings

[isa]
name = "ARMv7E-M"
architecture = "ARM"
word_size = 32
endianness = "little"

[instruction_timings]
alu = 1              # ADD, SUB, MOV, etc.
shift = 1            # LSL, LSR, ASR, ROR
mul = 1              # MUL (single cycle on Cortex-M4)
div = 12             # SDIV, UDIV
load = 2             # LDR
store = 2            # STR
branch = 1           # B, BL
branch_cond = 1      # BEQ, BNE, etc. (predicted taken)
branch_miss = 3      # Branch misprediction penalty

Layer 2: Core Configuration

CPU core microarchitecture details

[core]
name = "Cortex-M4"
isa = "armv7e-m"

[core.pipeline]
stages = 3
type = "in-order"

[core.cache.instruction_cache]
size_kb = 16
line_size_bytes = 32
associativity = 4
replacement_policy = "LRU"
hit_latency = 1
miss_latency = 10

[core.memory]
load_buffer_size = 4
store_buffer_size = 4

[core.memory.latency]
type = "fixed"
cycles = 10

Layer 3: SoC Configuration

System-on-Chip with frequency and memory regions

[soc]
name = "STM32F746"
core = "cortex-m7"
cpu_frequency_mhz = 216

[[soc.memory_regions]]
name = "FLASH"
start_address = "0x08000000"
size_bytes = 1048576
type = "ROM"
wait_states = 7

[[soc.memory_regions]]
name = "SRAM1"
start_address = "0x20000000"
size_bytes = 327680
type = "RAM"
wait_states = 0

Layer 4: Board Configuration

Specific board implementation with inheritance

[board]
name = "STM32F746-Discovery"
description = "STMicroelectronics STM32F746G-DISCO"
inherits = "socs/stm32f746"  # Inherit from SoC config

[board.clock]
frequency_mhz = 216  # Can override SoC frequency
crystal_mhz = 25

[board.memory.flash]
start_address = "0x08000000"
size_bytes = 1048576

[board.memory.sram]
start_address = "0x20000000"
size_bytes = 327680

User Custom Configurations

Users can define custom boards in config/boards/user/

# config/boards/user/my-custom-board.toml
[board]
name = "My Custom Board"
inherits = "socs/stm32h743"

[board.clock]
frequency_mhz = 400  # Override frequency

# Add custom memory regions
[[board.memory_regions]]
name = "EXTERNAL_SDRAM"
start_address = "0xC0000000"
size_bytes = 8388608
type = "RAM"

Validation Rules

• All ISA references must exist in config/isa/
• Core must reference valid ISA
• SoC must reference valid core
• Board must reference valid SoC or core
• No circular inheritance dependencies
• Memory regions must not overlap
• Frequency must be positive integer
• Cache sizes must be power of 2

CLI Usage

# List available boards
lale list-boards

# Validate board configuration
lale validate-board platforms/stm32f746-discovery

# Export resolved configuration
lale export-board platforms/stm32f746-discovery > resolved.toml

# Run analysis with board config
lale analyze ./data/firmware --board platforms/stm32f746-discovery