Re: [PATCH v2 5/6] powerpc/pseries/iommu: Make use of DDW even if it does not map the partition
From: Leonardo Bras
Date: Wed Jul 01 2020 - 20:54:51 EST
On Thu, 2020-07-02 at 10:31 +1000, Alexey Kardashevskiy wrote:
> > In fact, there is a lot of places in this file where it's called direct
> > window. Should I replace everything?
> > Should it be in a separated patch?
>
> If it looks simple and you write a nice commit log explaining all that
> and why you are not reusing the existing ibm,dma-window property
> for that - sure, do it :)
Nice, I will do that :)
> (to provide a clue what "reset" will reset to? is there any other
> reason?)
That's the main reason here.
The way I perceive this, ibm,dma-window should only point to the
default DMA window, which is guaranteed to always be the same, even if
it's destroyed and re-created. So there I see no point destroying /
overwriting it.
On the other hand, I also thought about using a new node name for this
window, but it would be very troublesome and I could see no real gain.
Thanks !