Thanks for the response.
I tried to launch the qemu with ref405ep and got the below error.
[osman@osci ~]$ qemu-system-ppc -nodefconfig -no-user-config -nodefaults
-no-reboot -nographic -serial stdio -cpu 405D2 -machine ref405ep -m 2047
-net nic,model=virtio,macaddr=$macaddr -net user$QEMU_HOSTFWD -drive
file=powerpc-qemu.img,if=virtio,index=0,format=qcow2 -drive
file=scratch.img,if=virtio,index=1,format=qcow2 -virtfs
local,id=work,path=`pwd`,security_model=none,mount_tag=work -boot menu=off
-kernel ppcqemu-vmlinux-stable
qemu-system-ppc: Could not load PowerPC BIOS 'ppc405_rom.bin'
[osman@osci ~]$
[osman@osci ~]$ qemu-system-ppc -nodefconfig -no-user-config -nodefaults
-no-reboot -nographic -serial stdio -machine ref405ep -m 2047 -net
nic,model=virtio,macaddr=$macaddr -net user$QEMU_HOSTFWD -drive
file=powerpc-qemu.img,if=virtio,index=0,format=qcow2 -drive
file=scratch.img,if=virtio,index=1,format=qcow2 -virtfs
local,id=work,path=`pwd`,security_model=none,mount_tag=work -boot menu=off
-kernel ppcqemu-vmlinux-stable
qemu-system-ppc: Could not load PowerPC BIOS 'ppc405_rom.bin'
[osman@osci ~]$
Same error message is observed even with "taihu" as well.