multicore-amp

Multicore AMP — Dual-Core Application

Demonstrates asymmetric multiprocessing (AMP) with EoS. The primary core produces data into a spinlock-protected shared memory ring buffer, while the secondary core consumes it and sends IPI notifications back.

What it demonstrates

• Multicore initialization in AMP mode with eos_multicore_init(EOS_MP_AMP)
• Starting a secondary core with eos_core_start()
• Shared memory creation with eos_shmem_create()
• Spinlock-protected ring buffer for cross-core data transfer
• Inter-Processor Interrupts with eos_ipi_send() / eos_ipi_register_handler()
• Memory barriers via spinlock internals

Architecture

┌─────────────────┐            ┌─────────────────┐
│    Core 0       │            │    Core 1        │
│   (Primary)     │            │  (Secondary)     │
│                 │            │                  │
│  producer_task  │   shmem    │  secondary_main  │
│      │          │   ring     │       │          │
│      ▼          │   buffer   │       ▼          │
│  ringbuf_write ─┼───────────►│  ringbuf_read   │
│                 │  spinlock  │       │          │
│  ipi_handler ◄──┼────────────┼── eos_ipi_send  │
└─────────────────┘            └─────────────────┘

Modules used

Module	Header	Functions
Multicore	eos/multicore.h	eos_multicore_init, eos_core_start, eos_core_count, eos_core_id
Spinlock	eos/multicore.h	eos_spin_init, eos_spin_lock, eos_spin_unlock
IPI	eos/multicore.h	eos_ipi_send, eos_ipi_register_handler
Shared Memory	eos/multicore.h	eos_shmem_create, eos_shmem_close
Kernel	eos/kernel.h	eos_kernel_init, eos_task_create

How to build

cmake -B build -DEOS_PRODUCT=iot -DEOS_ENABLE_MULTICORE=1
cmake --build build
./build/multicore-amp

Expected output

=== EoS Multicore AMP Demo ===
[core-0] Primary core running, 2 cores available
[core-0] Shared memory created: 4096 bytes at 0x...
[core-0] Starting core 1...
[core-0] Starting kernel...
[core-0] Producer task started
[core-1] Secondary core started
[core-0] Wrote value: 1
[core-1] Read value: 1 (processed=0)
[core-0] IPI received from core 1: data=0x00000001
[core-0] Wrote value: 2
[core-1] Read value: 2 (processed=1)
...
[core-0] Producer done
[core-1] Secondary core done (processed 20 messages)
=== Multicore demo complete ===