Re: [Qemu-devel] [PATCH v3 0/4] tcg: support heterogenous CPU clusters

[Peter Maydell]

On Mon, 21 Jan 2019 at 15:22, Peter Maydell <address@hidden> wrote:
>
> In the process of debugging my board code that uses this
> feature, I realized I needed to support the CPU object
> not being a direct child of the cluster object, which
> also lead me to the object_child_foreach_recursive()
> function which is a neater way to iterate children anyway.
> I also figured out we could add an assert which catches
> most "parenting CPU vs cluster realize ordering" bugs.
>
> Only patch 2 has changed here, others are already reviewed.
>
> Changes v2->v3:
>
>  * allow CPU objects to be indirect children of the cluster;
>    this is useful for ARMv7M, where the CPU object is a child
>    of the armv7m container and the board code that sets up
>    the cluster object only has the armv7m container object:
>    this is done by using object_child_foreach_recursive()
>    rather than an open-coded child iteration
>  * add an assertion that the cluster has at least one CPU,
>    which catches the easiest-to-make errors when creating
>    and populating the cluster

Oops, I should have tested this a bit more carefully before
sending it out. It needs an extra "patch 0" adding at the
start which makes xlnx_zynqmp_create_rpu() not create the
rpu-cluster object if there aren't any RPUs to put in it.
Otherwise we hit the new assertion when starting the
xlnx-zcu102 board with fewer than 5 CPUs. I'll send that
patch out in a second (but won't bother to re-roll the
entire patchset).

thanks
-- PMM