On Wed, Feb 06, 2019 at 02:45:34PM +0100, Christian Zigotzky wrote:

I patched the source code from the Git 'powerpc-dma.6' with your patch 
today. Unfortunately the P.A. Semi Ethernet doesn't work with the patched 
Git kernel.

After that I tried it with the patch applied over the working setup again 
(powerpc/dma: use the dma_direct mapping routines). Unfortunately after 
compiling
and booting, the P.A. Semi Ethernet doesn't work either.

The last good one was 29e7e2287e196f48fe5d2a6e017617723ea979bf
("dma-direct: we might need GFP_DMA for 32-bit dma masks"), if I
remember correctly.  powerpc/dma: use the dma_direct mapping routines
was the one that you said makes the pasemi ethernet stop working.

Can you post the dmesg from the failing runs?