SUN7i - bananapi Ethernet

hi,

i just built and started most current mainline u-boot for my bananapi board.

I have the problem, that ethernet doesn't work at all:

U-Boot 2016.03-rc1-00196-gfdb4f0e (Feb 16 2016 - 22:05:33 +0100) Allwinner Technology

CPU:   Allwinner A20 (SUN7I)
I2C:   ready
DRAM:  1 GiB
MMC:   SUNXI SD/MMC: 0
Setting up a 720x576i composite-pal console (overscan 32x20)
In:    serial
Out:   vga
Err:   vga
SCSI:  SUNXI SCSI INIT
SATA link 0 timeout.
AHCI 0001.0100 32 slots 1 ports 3 Gbps 0x1 impl SATA mode
flags: ncq stag pm led clo only pmp pio slum part ccc apst
Net:   eth0: ethernet at 01c50000

=> dhcp
ethernet at 01c50000 Waiting for PHY auto negotiation to complete......... TIMEOUT !
ethernet at 01c50000: No link.
=>

i can remember that this worked in the past.
I also tried to start some linux, there ethernet is working. But just working, not very well, if i send out pakets with >512byte they get lost.

i suspect there is something wrong with the connection between phy and mac.

is there anybody who has working ethernet on banana pi ?

best regards,
Hannes