Re: [PATCH] hw/pci-host: Allow extended config space access for Designware PCIe host

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Aug 09, 2023 at 10:22:50AM +0000, Jason Chien wrote:
> In pcie_bus_realize(), a root bus is realized as a PCIe bus and a non-root
> bus is realized as a PCIe bus if its parent bus is a PCIe bus. However,
> the child bus "dw-pcie" is realized before the parent bus "pcie" which is
> the root PCIe bus. Thus, the extended configuration space is not accessible
> on "dw-pcie". The issue can be resolved by adding the
> PCI_BUS_EXTENDED_CONFIG_SPACE flag to "pcie" before "dw-pcie" is realized.
> 
> Signed-off-by: Jason Chien <jason.chien@sifive.com>

I think we should fix the order of initialization rather than
hack around it.

> ---
>  hw/pci-host/designware.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/pci-host/designware.c b/hw/pci-host/designware.c
> index 9e183caa48..388d252ee2 100644
> --- a/hw/pci-host/designware.c
> +++ b/hw/pci-host/designware.c
> @@ -694,6 +694,7 @@ static void designware_pcie_host_realize(DeviceState *dev, Error **errp)
>                                       &s->pci.io,
>                                       0, 4,
>                                       TYPE_PCIE_BUS);
> +    pci->bus->flags |= PCI_BUS_EXTENDED_CONFIG_SPACE;
>  
>      memory_region_init(&s->pci.address_space_root,
>                         OBJECT(s),
> -- 
> 2.17.1