Re: [PATCH 00/10] fix swiotlb-xen for RPi4

From: Roman Shaposhnik
Date: Wed May 20 2020 - 19:51:37 EST


On Wed, May 20, 2020 at 4:45 PM Stefano Stabellini
<sstabellini@xxxxxxxxxx> wrote:
>
> Hi all,
>
> This series is a collection of fixes to get Linux running on the RPi4 as
> dom0.
>
> Conceptually there are only two significant changes:
>
> - make sure not to call virt_to_page on vmalloc virt addresses (patch
> #1)
> - use phys_to_dma and dma_to_phys to translate phys to/from dma
> addresses (all other patches)
>
> In particular in regards to the second part, the RPi4 is the first
> board where Xen can run that has the property that dma addresses are
> different from physical addresses, and swiotlb-xen was written with the
> assumption that phys addr == dma addr.
>
> This series adds the phys_to_dma and dma_to_phys calls to make it work.

Great to see this! Stefano, any chance you can put it in a branch some place
so I can test the final version?

Thanks,
Roman.