Downloading & Building U-Boot.sh

#!/bin/bash

# 1. Update package lists
echo "Updating package lists..."
sudo apt update

# 2. Install Dependencies
# Combined into a single command for efficiency.
# Removed duplicate entries (device-tree-compiler).
echo "Installing dependencies..."
sudo apt install -y \
    gcc-arm-linux-gnueabihf \
    build-essential \
    git \
    device-tree-compiler \
    qemu-system-arm \
    flex \
    bison \
    libssl-dev \
    bc

# 3. Clone U-Boot Repository
echo "Cloning U-Boot repository..."
git clone git://git.denx.de/u-boot.git
cd u-boot || { echo "Failed to enter u-boot directory"; exit 1; }

# 4. Checkout specific version
# Corrected typo from 'v.2023.10' to standard tag format 'v2023.10'
echo "Checking out version v2023.10..."
git checkout v2023.10

# 5. Set Environment Variables
# Setting these exports ensures the makefile targets the correct architecture
export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabihf-

# 6. Configure U-Boot for Raspberry Pi Zero W
# 'rpi_0_w_defconfig' is the specific configuration for RPi Zero W
echo "Configuring U-Boot..."
make rpi_0_w_defconfig

# 7. Build U-Boot
# -j$(nproc) uses all available CPU cores to speed up compilation
echo "Building U-Boot..."
make -j$(nproc)

# 8. Test U-Boot on QEMU
echo "Starting QEMU..."
# Note: Ensure you have a QEMU version that supports the 'raspi0' machine
qemu-system-arm \
  -M raspi0 \
  -m 512M \
  -nographic \
  -kernel u-boot