[HELP] Need help about quemu + u-root + x86 Linux kernel running in sd card like quemu + grub2 + x86 Linux kernel way

[Simon Glass]

Hi,

On Fri, 18 Nov 2022 at 21:53, 黄蓉刚 <happy.every.day at 126.com> wrote:
>
> 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
>
> print
>
> 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?

The instructions in the documentation work OK for me:

https://u-boot.readthedocs.io/en/latest/board/emulation/qemu-arm.html

Can you try that first and then go from there?

Regards,
Simon