November 19, 2022
Dear All,
Execute me. I need your help.
I am interested in qemu x86_64 and I have a problem that I want to input u-boot into a sdcard file and start Linux with the sdcard file, like grub-install(grub2) way.
The grub2 method (Method 1) is right, I want to use u-boot method (Method 2) to bootloader Linux kernel in x86. I guess that it needs write a program like grub-install to reach this aim.
Please help me to give a clear way like grub-install way. Thanks!
My steps:
cd ~/Code/kernel_sources
git clone https://github.com/qemu/u-boot.git
git checkout v2022.10-rc4
git reset --hard
cd ~/Code/kernel_sources/u-boot
export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabi-
make distclean
make vexpress_ca9x4_defconfig
make -j4 all
# Busybox and rootfs is ready
...
# Kernel
cd ~/Code/kernel_sources/linux-4.19.256
export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabi-
make clean
make bzImage -j2 ARCH=arm CROSS_COMPLIE=arm-linux-gnueabi-
make dtbs
cd ~/Code/kernel_sources/linux-4.19.256
# Create rootfs.img
sudo sh -c 'find . | cpio -o --format=newc > ../initrd.img'
# Common disk method
cd ~/Code/kernel_sources/linux-4.19.256
rm -rf busybox_u-boot_64M_4.19.256.img
dd if=/dev/zero of=busybox_u-boot_64M_4.19.256.img bs=1 seek=63MiB count=1024
cd ~/Code/kernel_sources/linux-4.19.256
sudo parted busybox_u-boot_64M_4.19.256.img
mklabel msdos
mkpart primary ext4 2MiB 98%
toggle 1 boot
quit
sudo kpartx -a busybox_u-boot_64M_4.19.256.img
echo y | sudo mkfs.ext4 /dev/mapper/loop0p1
cd ~/Code/kernel_sources/linux-4.19.256
sudo rm -rf /mnt/rootfs/*
sudo mkdir -p /mnt/rootfs/boot/
sudo cp arch/arm/boot/zImage /mnt/rootfs/boot/zImage
sudo cp initrd.img /mnt/rootfs/boot/initrd.img
# Method 1(Grub2):
# Common disk method + Grub method
cd ~/Code/kernel_sources/linux-4.19.256/
sudo losetup /dev/loop0 busybox_grub_2G_4.19.256.img
sudo kpartx -a /dev/loop0
sudo grub-install --target=i386-pc --recheck --no-floppy --boot-directory=/mnt/rootfs/boot/ /dev/loop0
cd /mnt/rootfs/boot/grub/
sudo sh -c "cat > grub.cfg << EOF
set timeout=5
set default=0
menuentry 'Linux 4.19.256, busybox, root=/dev/sda2' {
linux /boot/zImage root=/dev/sda2
initrd /boot/initrd.img
}
menuentry 'Reboot' {
reboot
}
menuentry 'Shutdown' {
halt
}
EOF"
cd ~/Code/kernel_sources/linux-4.19.256
qemu-system-x86_64 -m 1024M -drive format=raw,file=busybox_grub_2G_4.19.256.img -curses
It can run successfully.
# Method 2(U-boot):
# Common disk method + U-boot method
cd ~/Code/kernel_sources/linux-4.19.256
dd if=~/Code/kernel_sources/u-boot/u-boot.bin of=busybox_u-boot_64M_4.19.256_usb.img conv=notrunc bs=1
cd ~/Code/kernel_sources/linux-4.19.256
qemu-system-arm -M vexpress-a9 \
-nographic \
-m 1024M \
-sd ./busybox_u-boot_64M_4.19.256.img
...
It's can't start u-boot.
How use u-boot in sdcard file like grub-install?
Thanks!
Sincerely,
Ronggang Huang
2022.11.19