Re: [Qemu-devel] [PATCH v2] pci: Return PCI_INTX_DISABLED when no bus INTx routing support

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-10-18 00:13, Alex Williamson wrote:
> Rather than assert, simply return PCI_INTX_DISABLED when we don't
> have a pci_route_irq_fn.  PIIX already returns DISABLED for an
> invalid pin, so users already deal with this state.  Users of this
> interface should only be acting on an ENABLED or INVERTED return
> value (though we really have no support for INVERTED).  Also
> complain loudly when we hit this so we don't forget it's missing.
> 
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> ---
> 
> v2: Turn up the annoyance factor for hitting this
> 
>  hw/pci.c |    8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index 83d262a..6a66b32 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -1094,7 +1094,13 @@ PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin)
>           pin = bus->map_irq(dev, pin);
>           dev = bus->parent_dev;
>      } while (dev);
> -    assert(bus->route_intx_to_irq);
> +
> +    if (!bus->route_intx_to_irq) {
> +        error_report("PCI: Bug - unimplemented PCI INTx routing (%s)\n",
> +                     object_get_typename(OBJECT(bus->qbus.parent)));
> +        return (PCIINTxRoute) { PCI_INTX_DISABLED, -1 };
> +    }
> +
>      return bus->route_intx_to_irq(bus->irq_opaque, pin);
>  }
>  
> 

I'm fine with this. I also see this as dead code in x86 (any x86 chipset
will support this API, for sure), but maybe it helps on other archs. So:

Acked-by: Jan Kiszka <jan.kiszka@siemens.com>

Jan

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