use generic DMA mapping code in powerpc V4

[Christian Zigotzky]

Please don’t merge this code. We are still testing and trying to figure out where the problems are in the code.

— Christian

Sent from my iPhone

> On 6. Dec 2018, at 11:55, Christian Zigotzky <chzigotzky at xenosoft.de> wrote:
> 
>> On 05 December 2018 at 3:05PM, Christoph Hellwig wrote:
>> 
>> Thanks.  Can you try a few stepping points in the tree?
>> 
>> First just with commit 7fd3bb05b73beea1f9840b505aa09beb9c75a8c6
>> (the first one) applied?
>> 
>> Second with all commits up to 5da11e49df21f21dac25a2491aa788307bdacb6b
>> 
>> And if that still works with commits up to
>> c1bfcad4b0cf38ce5b00f7ad880d3a13484c123a
>> 
> Hi Christoph,
> 
> I undid the commit 7fd3bb05b73beea1f9840b505aa09beb9c75a8c6 with the following command:
> 
> git checkout 7fd3bb05b73beea1f9840b505aa09beb9c75a8c6
> 
> Result: PASEMI onboard ethernet works again and the P5020 board boots.
> 
> I will test the other commits in the next days.
> 
> @All
> It is really important, that you also test Christoph's work on your PASEMI and NXP boards. Could you please help us with solving the issues?
> 
> 'git clone git://git.infradead.org/users/hch/misc.git -b powerpc-dma.5 a'
> 
> Thanks,
> Christian
>