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.


Cheers,

Stefano

I would like to ask the maintainers, Juergen, Boris, Konrad, whether you
have any more feedback before I send v2 of the series.

Cheers,

Stefano


On Wed, 20 May 2020, Stefano Stabellini 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.
> 
> 
> Cheers,
> 
> Stefano
> 

On 6/2/20 5:51 PM, Stefano Stabellini wrote:
> I would like to ask the maintainers, Juergen, Boris, Konrad, whether you
> have any more feedback before I send v2 of the series.


I think I only had one comment and that's all. Most were from Julien.


-boris


>
> Cheers,
>
> Stefano
>
>
> On Wed, 20 May 2020, Stefano Stabellini 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.
>>
>>
>> Cheers,
>>
>> Stefano
>>

On Wed, May 20, 2020 at 4:45 PM Stefano Stabellini
<sstabellini@kernel.org> 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.

On Wed, 20 May 2020, Roman Shaposhnik wrote:
> On Wed, May 20, 2020 at 4:45 PM Stefano Stabellini
> <sstabellini@kernel.org> 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?

Here it is, but keep in mind that it is based on Linux master (because
it is meant to go upstream):

  git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen.git fix-rip4-v1