Mainline Kernel on Western Digital EX2 (no replies)

Hello

I'm trying to run Mainline Kernel on the Western Digital EX2 NAS (Armada 370). But if I try to boot the built Kernel it stops without any Kernel output. I've used the Devicetree armada-370-netgear-rn102.dts which should at least get it booting till the missing rootfs message.

Serial Port should be correct, the vendor bootargs has ttyS0 and I use serial0 in the devicetree.

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mvebu_v7_defconfig
make LOADADDR=0x00008000 ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- -j5
cat arch/arm/boot/dts/armada-370-netgear-rn102.dtb >> arch/arm/boot/zImage 
make LOADADDR=0x00008000 ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- uImage

Marvell>> set serverip 172.16.90.138
Marvell>> dhcp
BOOTP broadcast 1
*** Unhandled DHCP Option in OFFER/ACK: 44
*** Unhandled DHCP Option in OFFER/ACK: 44
DHCP client bound to address 172.16.90.109
Marvell>> tftpboot 1200000 uImage
Using egiga1 device
TFTP from server 172.16.90.138; our IP address is 172.16.90.109
Filename 'uImage'.
Load address: 0x1200000
Loading: #################################################################
	 #################################################################
	 #################################################################
	 #################################################################
	 #################################################################
	 #################################################################
	 #####
done
Bytes transferred = 5795076 (586d04 hex)
Marvell>> bootm 0x1200000
## Booting image at 01200000 ...
## Booting kernel from Legacy Image at 01200000 ...
   Image Name:   Linux-5.12.0-g69f737ed3a1c-dirty
   Created:      2021-05-05  23:20:10 UTC
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    5795012 Bytes = 5.5 MiB
   Load Address: 00008000
   Entry Point:  00008000
   Verifying Checksum ... OK
   Loading Kernel Image ... OK
OK

Starting kernel ...