[PULL 06/38] hw/arm/virt: Support cluster level in DT cpu-map

[Peter Maydell]

From: Yanan Wang <wangyanan55@huawei.com>

Support one cluster level between core and physical package in the
cpu-map of Arm/virt devicetree. This is also consistent with Linux
Doc "Documentation/devicetree/bindings/cpu/cpu-topology.txt".

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Message-id: 20220107083232.16256-3-wangyanan55@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/arm/virt.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 688d8736909..177db1da12e 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -434,9 +434,8 @@ static void fdt_add_cpu_nodes(const VirtMachineState *vms)
          * can contain several layers of clustering within a single physical
          * package and cluster nodes can be contained in parent cluster nodes.
          *
-         * Given that cluster is not yet supported in the vCPU topology,
-         * we currently generate one cluster node within each socket node
-         * by default.
+         * Note: currently we only support one layer of clustering within
+         * each physical package.
          */
         qemu_fdt_add_subnode(ms->fdt, "/cpus/cpu-map");
 
@@ -446,14 +445,16 @@ static void fdt_add_cpu_nodes(const VirtMachineState *vms)
 
             if (ms->smp.threads > 1) {
                 map_path = g_strdup_printf(
-                    "/cpus/cpu-map/socket%d/cluster0/core%d/thread%d",
-                    cpu / (ms->smp.cores * ms->smp.threads),
+                    "/cpus/cpu-map/socket%d/cluster%d/core%d/thread%d",
+                    cpu / (ms->smp.clusters * ms->smp.cores * ms->smp.threads),
+                    (cpu / (ms->smp.cores * ms->smp.threads)) % 
ms->smp.clusters,
                     (cpu / ms->smp.threads) % ms->smp.cores,
                     cpu % ms->smp.threads);
             } else {
                 map_path = g_strdup_printf(
-                    "/cpus/cpu-map/socket%d/cluster0/core%d",
-                    cpu / ms->smp.cores,
+                    "/cpus/cpu-map/socket%d/cluster%d/core%d",
+                    cpu / (ms->smp.clusters * ms->smp.cores),
+                    (cpu / ms->smp.cores) % ms->smp.clusters,
                     cpu % ms->smp.cores);
             }
             qemu_fdt_add_path(ms->fdt, map_path);
-- 
2.25.1