We can see v4 has different partition layout!
v3:
Creating 7 MTD partitions on "raspi":
0x000000000000-0x000000020000 : "boot"
0x000000020000-0x000000160000 : "kernel"
0x000000160000-0x0000007c0000 : "rootfs"
mtd: partition "rootfs" set to be root filesystem
0x0000007c0000-0x0000007d0000 : "config"
0x0000007d0000-0x0000007e0000 : "romfile"
0x0000007e0000-0x0000007f0000 : "rom"
0x0000007f0000-0x000000800000 : "radio"
v4:
Creating 7 MTD partitions on "raspi":
0x000000030000-0x000000050000 : "boot"
0x000000050000-0x000000190000 : "kernel"
0x000000190000-0x0000007c0000 : "rootfs"
mtd: partition "rootfs" set to be root filesystem
0x0000007c0000-0x0000007d0000 : "config"
0x0000007d0000-0x0000007e0000 : "romfile"
0x0000007e0000-0x0000007f0000 : "rom"
0x0000007f0000-0x000000800000 : "radio"