Re: Regression with commit PCI: mvebu: Convert to PCI emulated bridge config space

["Luís Mendes" <luis.p.mendes@gmail.com>]

Hi Thomas,

Thanks a lot for your quick reply and patch, but unfortunately the
problem remains the same with the patch applied.

How can I help to further pin down the issue?

Regards,
Luís

---
Luís Mendes, Researcher, Instituto Superior Técnico
Hardware and Software engineer
http://tecnico.ulisboa.pt/

On Tue, Dec 18, 2018 at 2:34 PM Thomas Petazzoni
<thomas.petazzoni@bootlin.com> wrote:
>
> Hello Luis,
>
> On Tue, 18 Dec 2018 14:47:02 +0100, Thomas Petazzoni wrote:
>
> > Thanks for the bug report! I have an idea of what could be causing
> > this, I've cooked a patch, I'm doing a build test. I of course won't be
> > able to test it as I don't have amdgpu hardware, but I'll share the
> > patch with you for testing.
>
> Could you try the below patch:
>
> diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
> index fa0fc46edb0c..62468415e063 100644
> --- a/drivers/pci/controller/pci-mvebu.c
> +++ b/drivers/pci/controller/pci-mvebu.c
> @@ -469,6 +469,23 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
>         return PCI_BRIDGE_EMUL_HANDLED;
>  }
>
> +static pci_bridge_emul_read_status_t
> +mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
> +                                    int reg, u32 *value)
> +{
> +       switch(reg) {
> +       case PCI_ROM_ADDRESS1:
> +               /* We don't support the PCI ROM mechanism */
> +               *value = 0;
> +               break;
> +
> +       default:
> +               return PCI_BRIDGE_EMUL_NOT_HANDLED;
> +       }
> +
> +       return PCI_BRIDGE_EMUL_HANDLED;
> +}
> +
>  static void
>  mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
>                                       int reg, u32 old, u32 new, u32 mask)
> @@ -555,6 +572,7 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
>  }
>
>  struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = {
> +       .read_base = mvebu_pci_bridge_emul_base_conf_read,
>         .write_base = mvebu_pci_bridge_emul_base_conf_write,
>         .read_pcie = mvebu_pci_bridge_emul_pcie_conf_read,
>         .write_pcie = mvebu_pci_bridge_emul_pcie_conf_write,
>
> If that fixes the problem for you, I'll send it as a proper patch with
> a commit log that explains the issue.
>
> Thanks,
>
> Thomas
> --
> Thomas Petazzoni, CTO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com