On Tue, Aug 25, 2020 at 05:52:17PM +0100, Leif Lindholm wrote:
> The sbsa-ref platform uses a minimal device tree to pass amount of memory
> as well as number of cpus to the firmware. However, when dumping that
> minimal dtb (with -M sbsa-virt,dumpdtb=<file>), the resulting blob
> generates a warning when decompiled by dtc due to lack of reg property.
>
> Add a simple reg property per cpu, representing a 64-bit MPIDR_EL1.
>
> Signed-off-by: Leif Lindholm <leif@nuviainc.com>
> ---
> hw/arm/sbsa-ref.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
> index f030a416fd..167c57a08b 100644
> --- a/hw/arm/sbsa-ref.c
> +++ b/hw/arm/sbsa-ref.c
> @@ -183,7 +183,22 @@ static void create_fdt(SBSAMachineState *sms)
> g_free(matrix);
> }
>
> + /*
> + * From Documentation/devicetree/bindings/arm/cpus.yaml
> + * On ARM v8 64-bit systems this property is required
> + * and matches the MPIDR_EL1 register affinity bits.
> + *
> + * * If cpus node's #address-cells property is set to 2
> + *
> + * The first reg cell bits [7:0] must be set to
> + * bits [39:32] of MPIDR_EL1.
> + *
> + * The second reg cell bits [23:0] must be set to
> + * bits [23:0] of MPIDR_EL1.
> + */
> qemu_fdt_add_subnode(sms->fdt, "/cpus");
> + qemu_fdt_setprop_cell(sms->fdt, "/cpus", "#address-cells", 2);
> + qemu_fdt_setprop_cell(sms->fdt, "/cpus", "#size-cells", 0x0);
>
> for (cpu = sms->smp_cpus - 1; cpu >= 0; cpu--) {
> char *nodename = g_strdup_printf("/cpus/cpu@%d", cpu);
> @@ -191,6 +206,7 @@ static void create_fdt(SBSAMachineState *sms)
> CPUState *cs = CPU(armcpu);
>
> qemu_fdt_add_subnode(sms->fdt, nodename);
> + qemu_fdt_setprop_u64(sms->fdt, nodename, "reg", cpu);
To obey the statement earlier shouldnt this be taken from the mp_affinity
variable in armcpu?
Graeme
>
> if (ms->possible_cpus->cpus[cs->cpu_index].props.has_node_id) {
> qemu_fdt_setprop_cell(sms->fdt, nodename, "numa-node-id",
> --
> 2.20.1
>