[Qemu-devel] [RFC PATCH v4 07/11] spapr: Enable CPU hotplug for pseries-2.5 and add CPU DRC DT entries

[Bharata B Rao <bharata@linux.vnet.ibm.com>]

Start supporting CPU hotplug from pseries-2.5 onwards. Add CPU
DRC (Dynamic Resource Connector) device tree entries.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
---
 hw/ppc/spapr.c         | 23 +++++++++++++++++++++++
 include/hw/ppc/spapr.h |  1 +
 2 files changed, 24 insertions(+)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 1d8a12a..a106980 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -955,6 +955,16 @@ static void spapr_finalize_fdt(sPAPRMachineState *spapr,
         _FDT(spapr_drc_populate_dt(fdt, 0, NULL, SPAPR_DR_CONNECTOR_TYPE_LMB));
     }
 
+    if (smc->dr_cpu_enabled) {
+        int offset = fdt_path_offset(fdt, "/cpus");
+        ret = spapr_drc_populate_dt(fdt, offset, NULL,
+                                    SPAPR_DR_CONNECTOR_TYPE_CPU);
+        if (ret < 0) {
+            fprintf(stderr, "Couldn't set up CPU DR device tree properties\n");
+            exit(1);
+        }
+    }
+
     _FDT((fdt_pack(fdt)));
 
     if (fdt_totalsize(fdt) > FDT_MAX_SIZE) {
@@ -1674,6 +1684,8 @@ static void ppc_spapr_init(MachineState *machine)
     long load_limit, fw_size;
     bool kernel_le = false;
     char *filename;
+    int smt = kvmppc_smt_threads();
+    int smp_max_cores = DIV_ROUND_UP(max_cpus, smp_threads);
 
     msi_supported = true;
 
@@ -1739,6 +1751,15 @@ static void ppc_spapr_init(MachineState *machine)
         spapr_validate_node_memory(machine);
     }
 
+    if (smc->dr_cpu_enabled) {
+        for (i = 0; i < smp_max_cores; i++) {
+            sPAPRDRConnector *drc =
+                spapr_dr_connector_new(OBJECT(spapr),
+                                       SPAPR_DR_CONNECTOR_TYPE_CPU, i * smt);
+            qemu_register_reset(spapr_drc_reset, drc);
+        }
+    }
+
     /* init CPUs */
     if (machine->cpu_model == NULL) {
         machine->cpu_model = kvm_enabled() ? "host" : "POWER7";
@@ -2213,6 +2234,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
     hc->unplug = spapr_machine_device_unplug;
 
     smc->dr_lmb_enabled = false;
+    smc->dr_cpu_enabled = false;
     fwc->get_dev_path = spapr_get_fw_dev_path;
     nc->nmi_monitor_handler = spapr_nmi;
 }
@@ -2376,6 +2398,7 @@ static void spapr_machine_2_5_class_init(ObjectClass *oc, void *data)
     mc->alias = "pseries";
     mc->is_default = 1;
     smc->dr_lmb_enabled = true;
+    smc->dr_cpu_enabled = true;
 }
 
 static const TypeInfo spapr_machine_2_5_info = {
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index b6cb0d0..9e364ba 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -36,6 +36,7 @@ struct sPAPRMachineClass {
 
     /*< public >*/
     bool dr_lmb_enabled; /* enable dynamic-reconfig/hotplug of LMBs */
+    bool dr_cpu_enabled; /* enable dynamic-reconfig/hotplug of CPUs */
 };
 
 /**
-- 
2.1.0