Re: [PATCH 07/12] powerpc: Use of_get_cpu_hwid()

From: Michael Ellerman
Date: Fri Oct 08 2021 - 07:01:35 EST


Rob Herring <robh@xxxxxxxxxx> writes:
> Replace open coded parsing of CPU nodes' 'reg' property with
> of_get_cpu_hwid().
>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> Cc: Paul Mackerras <paulus@xxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> arch/powerpc/kernel/smp.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
> index 9cc7d3dbf439..d96b0e361a73 100644
> --- a/arch/powerpc/kernel/smp.c
> +++ b/arch/powerpc/kernel/smp.c
> @@ -1313,18 +1313,13 @@ int __cpu_up(unsigned int cpu, struct task_struct *tidle)
> int cpu_to_core_id(int cpu)
> {
> struct device_node *np;
> - const __be32 *reg;
> int id = -1;
>
> np = of_get_cpu_node(cpu, NULL);
> if (!np)
> goto out;
>
> - reg = of_get_property(np, "reg", NULL);
> - if (!reg)
> - goto out;
> -
> - id = be32_to_cpup(reg);
> + id = of_get_cpu_hwid(np, 0);
> out:
> of_node_put(np);
> return id;

This looks OK to me.

All the systems I can find have a /cpus/#address-cells of 1, so the
change to use of_n_addr_cells() in of_get_cpu_hwid() should be fine.

I booted it on a bunch of systems with no issues.

Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>

cheers