Re: [Qemu-devel] [PATCH v3 1/3] spapr: introduce a fixed IRQ number space

["Cédric Le Goater" <clg@kaod.org>]

> --- a/hw/ppc/spapr_vio.c
> +++ b/hw/ppc/spapr_vio.c
> @@ -436,6 +436,9 @@ static void spapr_vio_busdev_reset(DeviceState *qdev)
>      }
>  }
>  
> +/* TODO : poor VIO device indexing ... */
> +static uint32_t vio_index;

I think we could also use (dev->reg & 0xff) as an index for 
the VIO devices.

The unit address of the virtual IOA is simply allocated using 
an increment of bus->next_reg, next_reg being initialized at
0x71000000.

I did not see any restrictions in the PAPR specs or in QEMU 
that would break the above.

C.


>  static void spapr_vio_busdev_realize(DeviceState *qdev, Error **errp)
>  {
>      sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
> @@ -476,10 +479,18 @@ static void spapr_vio_busdev_realize(DeviceState *qdev, Error **errp)
>      }
>  
>      if (!dev->irq) {
> -        dev->irq = spapr_irq_findone(spapr, &local_err);
> -        if (local_err) {
> -            error_propagate(errp, local_err);
> -            return;
> +        if (SPAPR_MACHINE_GET_CLASS(spapr)->legacy_irq_allocation) {
> +            dev->irq = spapr_irq_findone(spapr, &local_err);
> +            if (local_err) {
> +                error_propagate(errp, local_err);
> +                return;
> +            }
> +        } else {
> +            dev->irq = SPAPR_IRQ_VIO + vio_index++;
> +            if (dev->irq == SPAPR_IRQ_PCI_LSI) {
> +                error_setg(errp, "Too many VIO devices");
> +                return;
> +            }