Re: [PATCH 0/2] PCI: dwc: Add support to handle prefetchable memory separately

[Vidya Sagar]

On 02-Jun-20 10:37 PM, Gustavo Pimentel wrote:
> External email: Use caution opening links or attachments
>
>
> On Tue, Jun 2, 2020 at 11:9:38, Vidya Sagar <vidyas@xxxxxxxxxx> wrote:
>
> > In this patch series,
> > Patch-1
> > adds required infrastructure to deal with prefetchable memory region
> > information coming from 'ranges' property of the respective device-tree node
> > separately from non-prefetchable memory region information.
> > Patch-2
> > Adds support to use ATU region-3 for establishing the mapping between CPU
> > addresses and PCIe bus addresses.
> > It also changes the logic to determine whether mapping is required or not by
> > checking both CPU address and PCIe bus address for both prefetchable and
> > non-prefetchable regions. If the addresses are same, then, it is understood
> > that 1:1 mapping is in place and there is no need to setup ATU mapping
> > whereas if the addresses are not the same, then, there is a need to setup ATU
> > mapping. This is certainly true for Tegra194 and what I heard from our HW
> > engineers is that it should generally be true for any DWC based implementation
> > also.
> > Hence, I request Synopsys folks (Jingoo Han & Gustavo Pimentel ??) to confirm
> > the same so that this particular patch won't cause any regressions for other
> > DWC based platforms.
>
> Hi Vidya,
>
> Unfortunately due to the COVID-19 lockdown, I can't access my development
> prototype setup to test your patch.
> It might take some while until I get the possibility to get access to it
> again.
Hi Gustavo,
Did you find time to check this?
Adding Kishon and Alan as well to take a look at this and verify on 
their platforms if possible.

Thanks,
Vidya Sagar

> -Gustavo
>
> > Vidya Sagar (2):
> >    PCI: dwc: Add support to handle prefetchable memory separately
> >    PCI: dwc: Use ATU region to map prefetchable memory region
> >
> >   .../pci/controller/dwc/pcie-designware-host.c | 46 ++++++++++++++-----
> >   drivers/pci/controller/dwc/pcie-designware.c  |  6 ++-
> >   drivers/pci/controller/dwc/pcie-designware.h  |  8 +++-
> >   3 files changed, 45 insertions(+), 15 deletions(-)
> >
> > --
> > 2.17.1