Building QEMU for OpenBMC

Build QEMU from source when your distribution’s package lacks ast2600-evb support.

Table of Contents

1. When You Need This Guide
   1. Check Your QEMU Version
2. Option 1: Use OpenBMC’s Built-in QEMU (Recommended)
   1. Build QEMU via BitBake
   2. Use the Built QEMU
   3. Create a Convenience Script
3. Option 2: Build QEMU from Source
   1. Install Build Dependencies
   2. Clone and Build QEMU
   3. Install System-Wide (Optional)
   4. Install to Custom Location
4. Option 3: Use Container with QEMU
   1. Docker with QEMU
5. Verifying QEMU Setup
   1. Check Available Machines
   2. Test Run
6. Machine Selection Reference
7. Troubleshooting
   1. “Machine type not found”
   2. Build Fails with Missing Dependencies
   3. Slow Performance
8. Next Steps

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When You Need This Guide

Stock QEMU from Linux distribution package managers often lacks ASPEED machine support:

Distribution	Package QEMU Version	ast2600-evb Support
Ubuntu 20.04	QEMU 4.2	❌ No
Ubuntu 22.04	QEMU 6.2	⚠️ Partial
Ubuntu 24.04	QEMU 8.2	✅ Yes
Fedora 38+	QEMU 7.2+	✅ Yes
Debian 11	QEMU 5.2	❌ No
Debian 12	QEMU 7.2	✅ Yes

Check Your QEMU Version

# Check version
qemu-system-arm --version

# Check if ast2600-evb is available
qemu-system-arm -machine help | grep ast2600

If ast2600-evb is not listed, you need to build QEMU from source.

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Option 1: Use OpenBMC’s Built-in QEMU (Recommended)

The OpenBMC build system includes a QEMU recipe with full ASPEED support. This is the easiest option.

Build QEMU via BitBake

cd openbmc

# Initialize environment (if not already done)
. setup ast2600-evb

# Build QEMU native tool
bitbake qemu-system-native

# Find the built QEMU
ls tmp/work/x86_64-linux/qemu-system-native/*/image/usr/bin/qemu-system-arm

Use the Built QEMU

# Set path to OpenBMC's QEMU
QEMU_PATH="tmp/work/x86_64-linux/qemu-system-native/*/image/usr/bin"

# Run with OpenBMC's QEMU
$QEMU_PATH/qemu-system-arm -m 1G \
    -M ast2600-evb \
    -nographic \
    -drive file=tmp/deploy/images/ast2600-evb/obmc-phosphor-image-ast2600-evb.static.mtd,format=raw,if=mtd \
    -net nic \
    -net user,hostfwd=tcp::2222-:22,hostfwd=tcp::2443-:443,hostfwd=udp::2623-:623

Create a Convenience Script

#!/bin/bash
# save as: run-qemu.sh

OPENBMC_DIR="${OPENBMC_DIR:-$(pwd)}"
QEMU=$(find $OPENBMC_DIR/tmp/work/x86_64-linux/qemu-system-native -name qemu-system-arm -type f | head -1)
IMAGE="$OPENBMC_DIR/tmp/deploy/images/ast2600-evb/obmc-phosphor-image-ast2600-evb.static.mtd"

if [ ! -f "$QEMU" ]; then
    echo "Error: QEMU not found. Run 'bitbake qemu-system-native' first."
    exit 1
fi

$QEMU -m 1G \
    -M ast2600-evb \
    -nographic \
    -drive file=$IMAGE,format=raw,if=mtd \
    -net nic \
    -net user,hostfwd=tcp::2222-:22,hostfwd=tcp::2443-:443,hostfwd=udp::2623-:623

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Option 2: Build QEMU from Source

Build QEMU directly from upstream source for use outside the OpenBMC build environment.

Install Build Dependencies

# Ubuntu/Debian
sudo apt update
sudo apt install -y \
    git \
    build-essential \
    ninja-build \
    pkg-config \
    libglib2.0-dev \
    libpixman-1-dev \
    libslirp-dev \
    python3 \
    python3-venv

# Fedora
sudo dnf install -y \
    git \
    gcc \
    g++ \
    ninja-build \
    glib2-devel \
    pixman-devel \
    libslirp-devel \
    python3

Clone and Build QEMU

# Clone QEMU (use version 8.0+ for best ASPEED support)
git clone https://github.com/qemu/qemu.git
cd qemu
git checkout v8.2.0  # or latest stable

# Configure for ARM system emulation only (faster build)
./configure \
    --target-list=arm-softmmu \
    --enable-slirp \
    --disable-docs \
    --disable-werror

# Build (use -j for parallel compilation)
make -j$(nproc)

# Verify ast2600-evb is available
./build/qemu-system-arm -machine help | grep ast2600

Install System-Wide (Optional)

# Install to /usr/local
sudo make install

# Verify installation
qemu-system-arm --version
qemu-system-arm -machine help | grep ast2600

Install to Custom Location

# Install to home directory
./configure \
    --target-list=arm-softmmu \
    --prefix=$HOME/qemu \
    --enable-slirp

make -j$(nproc)
make install

# Add to PATH
echo 'export PATH="$HOME/qemu/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

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Option 3: Use Container with QEMU

Run QEMU inside a container that has proper ASPEED support.

Docker with QEMU

# Dockerfile.qemu
FROM ubuntu:24.04

RUN apt-get update && apt-get install -y \
    qemu-system-arm \
    && rm -rf /var/lib/apt/lists/*

WORKDIR /openbmc

# Build container
docker build -t openbmc-qemu -f Dockerfile.qemu .

# Run QEMU in container (mount image directory)
docker run -it --rm \
    -v $(pwd)/tmp/deploy/images:/images \
    -p 2222:2222 -p 2443:2443 -p 2623:2623/udp \
    openbmc-qemu \
    qemu-system-arm -m 1G -M ast2600-evb -nographic \
    -drive file=/images/ast2600-evb/obmc-phosphor-image-ast2600-evb.static.mtd,format=raw,if=mtd \
    -net nic \
    -net user,hostfwd=tcp::2222-:22,hostfwd=tcp::2443-:443,hostfwd=udp::2623-:623

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Verifying QEMU Setup

Check Available Machines

# List all ASPEED machines
qemu-system-arm -machine help | grep -i aspeed

# Expected output includes:
# ast2500-evb     Aspeed AST2500 EVB (ARM926EJ-S)
# ast2600-evb     Aspeed AST2600 EVB (Cortex-A7)
# palmetto-bmc    OpenPOWER Palmetto BMC (ARM926EJ-S)
# romulus-bmc     OpenPOWER Romulus BMC (ARM1176)
# witherspoon-bmc OpenPOWER Witherspoon BMC (ARM1176)

Test Run

# Quick test (will fail without image, but confirms QEMU works)
qemu-system-arm -M ast2600-evb -nographic -serial null
# Press Ctrl+A, X to exit

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Machine Selection Reference

Machine	SoC	CPU	Memory	Use Case
ast2600-evb	AST2600	Cortex-A7 (dual)	1GB	Modern development (recommended)
ast2500-evb	AST2500	ARM926EJ-S	512MB	Legacy compatibility
romulus-bmc	AST2500	ARM1176	256MB	IBM OpenPOWER reference
witherspoon-bmc	AST2500	ARM1176	256MB	IBM OpenPOWER reference

Use ast2600-evb for new development. It has more memory (1GB vs 256MB), a modern CPU, and represents current hardware.

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Troubleshooting

“Machine type not found”

qemu-system-arm: -M ast2600-evb: unsupported machine type

Solution: Your QEMU version is too old. Build from source using this guide.

Build Fails with Missing Dependencies

# Install all possible dependencies
sudo apt install -y \
    libglib2.0-dev libpixman-1-dev libslirp-dev \
    libcap-ng-dev libattr1-dev libaio-dev \
    libnuma-dev libseccomp-dev

Slow Performance

# Enable KVM if running ARM on ARM host
qemu-system-arm -M ast2600-evb -enable-kvm ...

# For x86 host, KVM won't help (cross-architecture)
# Allocate more CPU cores
qemu-system-arm -M ast2600-evb -smp 2 ...

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Next Steps

• First Build - Build and run OpenBMC
• Development Workflow - Iterate quickly with devtool

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Tested on: Ubuntu 22.04/24.04, Fedora 38/39, QEMU 7.2-8.2