[PATCH v11 09/11] s390x/cpu topology: add topology machine property

[Pierre Morel]

We keep the possibility to switch on/off the topology on newer
machines with the property topology=[on|off].

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
 include/hw/boards.h                |  3 +++
 include/hw/s390x/cpu-topology.h    |  8 +++-----
 include/hw/s390x/s390-virtio-ccw.h |  1 +
 hw/core/machine.c                  |  3 +++
 hw/s390x/cpu-topology.c            | 19 +++++++++++++++++++
 hw/s390x/s390-virtio-ccw.c         | 28 ++++++++++++++++++++++++++++
 util/qemu-config.c                 |  4 ++++
 qemu-options.hx                    |  6 +++++-
 8 files changed, 66 insertions(+), 6 deletions(-)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 311ed17e18..67147c47bf 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -379,6 +379,9 @@ struct MachineState {
     } \
     type_init(machine_initfn##_register_types)
 
+extern GlobalProperty hw_compat_7_2[];
+extern const size_t hw_compat_7_2_len;
+
 extern GlobalProperty hw_compat_7_1[];
 extern const size_t hw_compat_7_1_len;
 
diff --git a/include/hw/s390x/cpu-topology.h b/include/hw/s390x/cpu-topology.h
index 6fec10e032..f566394302 100644
--- a/include/hw/s390x/cpu-topology.h
+++ b/include/hw/s390x/cpu-topology.h
@@ -12,6 +12,8 @@
 
 #include "hw/qdev-core.h"
 #include "qom/object.h"
+#include "cpu.h"
+#include "hw/s390x/s390-virtio-ccw.h"
 
 #define S390_TOPOLOGY_CPU_IFL 0x03
 #define S390_TOPOLOGY_MAX_ORIGIN ((63 + S390_MAX_CPUS) / 64)
@@ -38,10 +40,6 @@ struct S390Topology {
 OBJECT_DECLARE_SIMPLE_TYPE(S390Topology, S390_CPU_TOPOLOGY)
 
 void s390_topology_new_cpu(S390CPU *cpu);
-
-static inline bool s390_has_topology(void)
-{
-    return false;
-}
+bool s390_has_topology(void);
 
 #endif
diff --git a/include/hw/s390x/s390-virtio-ccw.h 
b/include/hw/s390x/s390-virtio-ccw.h
index 89fca3f79f..d7602aedda 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -28,6 +28,7 @@ struct S390CcwMachineState {
     bool dea_key_wrap;
     bool pv;
     bool zpcii_disable;
+    bool cpu_topology;
     uint8_t loadparm[8];
     void *topology;
 };
diff --git a/hw/core/machine.c b/hw/core/machine.c
index aa520e74a8..4f46d4ef23 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -40,6 +40,9 @@
 #include "hw/virtio/virtio-pci.h"
 #include "qom/object_interfaces.h"
 
+GlobalProperty hw_compat_7_2[] = {};
+const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2);
+
 GlobalProperty hw_compat_7_1[] = {};
 const size_t hw_compat_7_1_len = G_N_ELEMENTS(hw_compat_7_1);
 
diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
index fc220bd8ac..c1550cc1e8 100644
--- a/hw/s390x/cpu-topology.c
+++ b/hw/s390x/cpu-topology.c
@@ -73,6 +73,25 @@ void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra)
     }
 }
 
+bool s390_has_topology(void)
+{
+    static S390CcwMachineState *ccw;
+    Object *obj;
+
+    if (ccw) {
+        return ccw->cpu_topology;
+    }
+
+    /* we have to bail out for the "none" machine */
+    obj = object_dynamic_cast(qdev_get_machine(),
+                              TYPE_S390_CCW_MACHINE);
+    if (!obj) {
+        return false;
+    }
+    ccw = S390_CCW_MACHINE(obj);
+    return ccw->cpu_topology;
+}
+
 /*
  * s390_topology_new_cpu:
  * @cpu: a pointer to the new CPU
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index f1a9d6e793..ebb5615337 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -710,6 +710,26 @@ bool hpage_1m_allowed(void)
     return get_machine_class()->hpage_1m_allowed;
 }
 
+static inline bool machine_get_topology(Object *obj, Error **errp)
+{
+    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
+
+    return ms->cpu_topology;
+}
+
+static inline void machine_set_topology(Object *obj, bool value, Error **errp)
+{
+    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
+
+    if (!get_machine_class()->topology_capable) {
+        error_setg(errp, "Property cpu-topology not available on machine %s",
+                   get_machine_class()->parent_class.name);
+        return;
+    }
+
+    ms->cpu_topology = value;
+}
+
 static void machine_get_loadparm(Object *obj, Visitor *v,
                                  const char *name, void *opaque,
                                  Error **errp)
@@ -809,6 +829,12 @@ static void ccw_machine_class_init(ObjectClass *oc, void 
*data)
                                    machine_set_zpcii_disable);
     object_class_property_set_description(oc, "zpcii-disable",
             "disable zPCI interpretation facilties");
+
+    object_class_property_add_bool(oc, "topology",
+                                   machine_get_topology,
+                                   machine_set_topology);
+    object_class_property_set_description(oc, "topology",
+            "enable CPU topology");
 }
 
 static inline void s390_machine_initfn(Object *obj)
@@ -818,6 +844,7 @@ static inline void s390_machine_initfn(Object *obj)
     ms->aes_key_wrap = true;
     ms->dea_key_wrap = true;
     ms->zpcii_disable = false;
+    ms->cpu_topology = true;
 }
 
 static const TypeInfo ccw_machine_info = {
@@ -888,6 +915,7 @@ static void ccw_machine_7_1_instance_options(MachineState 
*machine)
     s390_cpudef_featoff_greater(16, 1, S390_FEAT_PAIE);
     s390_set_qemu_cpu_model(0x8561, 15, 1, qemu_cpu_feat);
     ms->zpcii_disable = true;
+    ms->cpu_topology = true;
 }
 
 static void ccw_machine_7_1_class_options(MachineClass *mc)
diff --git a/util/qemu-config.c b/util/qemu-config.c
index 5325f6bf80..0a040552bd 100644
--- a/util/qemu-config.c
+++ b/util/qemu-config.c
@@ -240,6 +240,10 @@ static QemuOptsList machine_opts = {
             .name = "zpcii-disable",
             .type = QEMU_OPT_BOOL,
             .help = "disable zPCI interpretation facilities",
+        },{
+            .name = "topology",
+            .type = QEMU_OPT_BOOL,
+            .help = "disable CPU topology",
         },
         { /* End of list */ }
     }
diff --git a/qemu-options.hx b/qemu-options.hx
index eb38e5dc40..ef59b28a03 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -38,7 +38,8 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
     "                hmat=on|off controls ACPI HMAT support (default=off)\n"
     "                memory-backend='backend-id' specifies explicitly provided 
backend for main RAM (default=none)\n"
     "                
cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
-    "                zpcii-disable=on|off disables zPCI interpretation 
facilities (default=off)\n",
+    "                zpcii-disable=on|off disables zPCI interpretation 
facilities (default=off)\n"
+    "                topology=on|off disables CPU topology (default=off)\n",
     QEMU_ARCH_ALL)
 SRST
 ``-machine [type=]name[,prop=value[,...]]``
@@ -163,6 +164,9 @@ SRST
         Disables zPCI interpretation facilties on s390-ccw hosts.
         This feature can be used to disable hardware virtual assists
         related to zPCI devices. The default is off.
+
+    ``topology=on|off``
+        Disables CPU topology on for S390 machines starting with 
s390-ccw-virtio-7.3.
 ERST
 
 DEF("M", HAS_ARG, QEMU_OPTION_M,
-- 
2.31.1