Re: [PATCH] hw/ppc/spapr_pci.c: Use device_cold_reset() rather than device_legacy_reset()

[Cédric Le Goater]

On 10/14/22 16:28, Peter Maydell wrote:
> In spapr_phb_children_reset() we call device_legacy_reset() to reset any
> QOM children of the SPAPR PCI host bridge device. This will not reset
> any qbus such a child might own. Switch to device_cold_reset(), which will
> reset both the device and its buses. (If the child has no qbuses then
> there will be no change in behaviour.)
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> I couldn't figure out what exactly the QOM child objects are in this
> case -- the comment in spapr_phb_reset() suggests there's only one and
> it's the IOMMU? My guess is that they don't have any qbuses in any case.
> This patch was tested with 'make check' and 'make check-avocado' only.

If I understand correctly commit e28c16f61fee ("spapr_pci: Allow multiple
TCE tables per PHB"), spapr_phb_children_reset() was introduced to reset
the TYPE_SPAPR_TCE_TABLE objects.

Reviewed-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.

> ---
>   hw/ppc/spapr_pci.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 57c8a4f0855..7b7618d5da0 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -2045,7 +2045,7 @@ static int spapr_phb_children_reset(Object *child, void 
> *opaque)
>       DeviceState *dev = (DeviceState *) object_dynamic_cast(child, 
> TYPE_DEVICE);
>   
>       if (dev) {
> -        device_legacy_reset(dev);
> +        device_cold_reset(dev);
>       }
>   
>       return 0;