Re: [PATCH 2/3] cpu/a9mpcore: Add num priority bits property

[Peter Maydell]

On Fri, 14 Feb 2020 at 13:21, Sai Pavan Boddu
<address@hidden> wrote:
>
> Set number of priority bits property of gic as guided by machine
> configuration.
>
> Signed-off-by: Sai Pavan Boddu <address@hidden>
> ---
>  hw/cpu/a9mpcore.c         | 2 ++
>  include/hw/cpu/a9mpcore.h | 1 +
>  2 files changed, 3 insertions(+)
>
> diff --git a/hw/cpu/a9mpcore.c b/hw/cpu/a9mpcore.c
> index 1f8bc8a..eb1e752 100644
> --- a/hw/cpu/a9mpcore.c
> +++ b/hw/cpu/a9mpcore.c
> @@ -68,6 +68,7 @@ static void a9mp_priv_realize(DeviceState *dev, Error 
> **errp)
>      gicdev = DEVICE(&s->gic);
>      qdev_prop_set_uint32(gicdev, "num-cpu", s->num_cpu);
>      qdev_prop_set_uint32(gicdev, "num-irq", s->num_irq);
> +    qdev_prop_set_uint32(gicdev, "num-prio-bits", s->n_prio_bits);
>
>      /* Make the GIC's TZ support match the CPUs. We assume that
>       * either all the CPUs have TZ, or none do.
> @@ -167,6 +168,7 @@ static Property a9mp_priv_properties[] = {
>       * Other boards may differ and should set this property appropriately.
>       */
>      DEFINE_PROP_UINT32("num-irq", A9MPPrivState, num_irq, 96),
> +    DEFINE_PROP_UINT32("num-priority-bits", A9MPPrivState, n_prio_bits, 8),
>      DEFINE_PROP_END_OF_LIST(),

You should be able to just directly pass through the property
from the GIC object by calling
    object_property_add_alias(obj, "num-priority-bits", OBJECT(&s->gic),
                              "num-priority-bits", &error_abort);
at the end of a9mp_priv_initfn().

Then you don't need to have a DEFINE_PROP* for it, or a field in
the state struct, or manually pass the value on in realize.

(We don't do this for the existing num-irq and num-cpu properties
because in those cases this device itself needs to know the
values, as well as passing them on to other devices under it.)

thanks
-- PMM