Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

From: Michael Ellerman
Date: Thu Jun 20 2019 - 09:54:45 EST

Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> writes:
> On Wed, 2019-06-19 at 22:32 +1000, Michael Ellerman wrote:
>> Christoph Hellwig <hch@xxxxxx> writes:
>> > Any chance this could get picked up to fix the regression?
>> Was hoping Ben would Ack it. He's still powermac maintainer :)
>> I guess he OK'ed it in the other thread, will add it to my queue.
> Yeah ack. If I had written it myself, I would have made the DMA bits a
> variable and only set it down to 30 if I see that device in the DT
> early on, but I can't be bothered now, if it works, ship it :-)

OK, we can do that next release if someone's motivated.

> Note: The patch affects all ppc32, though I don't think it will cause
> any significant issue on those who don't need it.

Yeah. We could always hide it behind CONFIG_PPC_PMAC if it becomes a problem.