How I can get/dump full dtb file?

[Victor Martins]

Hi all (I´m new in this QEMU world).

In my tutorial to run Linux in QEMU/RISC-V I did this and all is OK:

$ qemu-system-riscv64 \
    -nographic \
    -machine virt \
    -kernel linux-5.19.1/arch/riscv/boot/Image \
    -append "root=/dev/vda ro console=ttyS0" \
    -drive file=busybox,format=raw,id=hd0 \
    -device virtio-blk-device,drive=hd0 \
    -netdev user,id=eth0 \
    -device virtio-net-device,netdev=eth0

After I made the dump of dtb like (using -machine dumpdtb) this without any error:

$ qemu-system-riscv64 \
    -nographic \
    -machine virt \
    -kernel linux-5.19.1/arch/riscv/boot/Image \
    -append "root=/dev/vda ro console=ttyS0" \
    -drive file=busybox,format=raw,id=hd0 \
    -device virtio-blk-device,drive=hd0 \
    -netdev user,id=eth0 \
    -device virtio-net-device,netdev=eth0 \

    -machine dumpdtb=riscv64-virt.dtb

And after I try use the dtb file and remove the virt board like this:

$ qemu-system-riscv64 \
    -nographic \
    -dtb ./riscv64-virt.dtb \
    -kernel linux-5.19.1/arch/riscv/boot/Image \
    -append "root=/dev/vda ro console=ttyS0" \
    -drive file=busybox,format=raw,id=hd0 \
    -device virtio-blk-device,drive=hd0 \
    -netdev user,id=eth0 \
    -device virtio-net-device,netdev=eth0

But don't work as before and I get this error:

$ qemu-system-riscv64: -device virtio-blk-device,

drive=hd0: No `virtio-bus´ bus found for device

`virtio-blk-device´

I feel that the dump operation dont extract the full Device Tree. My idea is to try to use only the dtb/dts. Is that possible?

Regards