Re: [PATCH v6 5/6] PCI: uniphier: Add iATU register support

[Kunihiko Hayashi]

Hi Rob,

On 2020/09/04 7:12, Rob Herring wrote:
> On Fri, Aug 21, 2020 at 1:05 AM Kunihiko Hayashi
> <hayashi.kunihiko@xxxxxxxxxxxxx> wrote:
> > On 2020/08/18 1:48, Rob Herring wrote:
> > > On Fri, Aug 7, 2020 at 4:25 AM Kunihiko Hayashi
> > > <hayashi.kunihiko@xxxxxxxxxxxxx> wrote:
> > > > This gets iATU register area from reg property. In Synopsys DWC version
> > > > 4.80 or later, since iATU register area is separated from core register
> > > > area, this area is necessary to get from DT independently.
> > > >
> > > > Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
> > > > ---
> > > >    drivers/pci/controller/dwc/pcie-uniphier.c | 5 +++++
> > > >    1 file changed, 5 insertions(+)
> > > >
> > > > diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > index 55a7166..93ef608 100644
> > > > --- a/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > +++ b/drivers/pci/controller/dwc/pcie-uniphier.c
> > > > @@ -471,6 +471,11 @@ static int uniphier_pcie_probe(struct platform_device *pdev)
> > > >           if (IS_ERR(priv->pci.dbi_base))
> > > >                   return PTR_ERR(priv->pci.dbi_base);
> > > >
> > > > +       priv->pci.atu_base =
> > > > +               devm_platform_ioremap_resource_byname(pdev, "atu");
> > > > +       if (IS_ERR(priv->pci.atu_base))
> > > > +               priv->pci.atu_base = NULL;
> > >
> > > Keystone has the same 'atu' resource setup. Please move its code to
> > > the DW core and use that.
> >
> > There are some platforms that pci.atu_base is set by other way.
> > The 'atu' code shouldn't be conflicted with the following existing code.
>
> No, it's not a conflict but needless duplication.

I see.

> >     drivers/pci/controller/dwc/pci-keystone.c:              atu_base = devm_platform_ioremap_resource_byname(pdev, "atu");
> >     drivers/pci/controller/dwc/pci-keystone.c:              pci->atu_base = atu_base;
> >     drivers/pci/controller/dwc/pcie-designware.c:                   pci->atu_base = pci->dbi_base + DEFAULT_DBI_ATU_OFFSET;
> >     drivers/pci/controller/dwc/pcie-intel-gw.c:     pci->atu_base = pci->dbi_base + data->pcie_atu_offset;
>
> This one should have had an 'atu' region in DT.
>
> >     drivers/pci/controller/dwc/pcie-tegra194.c:     pci->atu_base = devm_ioremap_resource(dev, atu_dma_res);
>
> Unfortunately, a different name was used. That is the mess which is
> the DW PCI controller.

Okay, this has already set atu_base, so ignore it for this patch.
 
> > So I'm not sure where to move the code in the DW core.
> > Is there any idea?
>
> You just need this and then remove the keystone code:
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c
> b/drivers/pci/controller/dwc/pcie-designware.c
> index b723e0cc41fb..680084467447 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -556,6 +556,8 @@ void dw_pcie_setup(struct dw_pcie *pci)
>                                         dw_pcie_iatu_unroll_enabled(pci))) {
>                  pci->iatu_unroll_enabled = true;
>                  if (!pci->atu_base)
> +                       pci->atu_base =
> devm_platform_ioremap_resource_byname(pdev, "atu");
> +               if (IS_ERR(pci->atu_base))
>                          pci->atu_base = pci->dbi_base + DEFAULT_DBI_ATU_OFFSET;
>          }
>          dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?

I've got it. I think I need to add a bit of code to this though,
I'll try to apply this and remove the duplicate code.

I'll separate this from other PER/AER patches and send new series.

Thank you,

---
Best Regards
Kunihiko Hayashi