hw/arm/virt: Add nvdimm hotplug support

This adds support for nvdimm hotplug events through GED
and enables nvdimm for the arm/virt. Now Guests with ACPI
can have both cold and hot plug of nvdimms.

Hot removal functionality is not yet supported.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20200421125934.14952-5-shameerali.kolothum.thodi@huawei.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

docs/specs/acpi_hw_reduced_hotplug.rst

@@ -63,7 +63,8 @@ GED IO interface (4 byte access)
     bits:
        0: Memory hotplug event
        1: System power down event
-    2-31: Reserved
+       2: NVDIMM hotplug event
+    3-31: Reserved
 
 **write_access:**
 

hw/acpi/generic_event_device.c

@@ -16,6 +16,7 @@
 #include "hw/acpi/generic_event_device.h"
 #include "hw/irq.h"
 #include "hw/mem/pc-dimm.h"
+#include "hw/mem/nvdimm.h"
 #include "hw/qdev-properties.h"
 #include "migration/vmstate.h"
 #include "qemu/error-report.h"
@@ -23,6 +24,7 @@
 static const uint32_t ged_supported_events[] = {
     ACPI_GED_MEM_HOTPLUG_EVT,
     ACPI_GED_PWR_DOWN_EVT,
+    ACPI_GED_NVDIMM_HOTPLUG_EVT,
 };
 
 /*
@@ -110,6 +112,11 @@ void build_ged_aml(Aml *table, const char *name, HotplugHandler *hotplug_dev,
                            aml_notify(aml_name(ACPI_POWER_BUTTON_DEVICE),
                                       aml_int(0x80)));
                 break;
+            case ACPI_GED_NVDIMM_HOTPLUG_EVT:
+                aml_append(if_ctx,
+                           aml_notify(aml_name("\\_SB.NVDR"),
+                                      aml_int(0x80)));
+                break;
             default:
                 /*
                  * Please make sure all the events in ged_supported_events[]
@@ -175,7 +182,11 @@ static void acpi_ged_device_plug_cb(HotplugHandler *hotplug_dev,
     AcpiGedState *s = ACPI_GED(hotplug_dev);
 
     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
-        acpi_memory_plug_cb(hotplug_dev, &s->memhp_state, dev, errp);
+        if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
+            nvdimm_acpi_plug_cb(hotplug_dev, dev);
+        } else {
+            acpi_memory_plug_cb(hotplug_dev, &s->memhp_state, dev, errp);
+        }
     } else {
         error_setg(errp, "virt: device plug request for unsupported device"
                    " type: %s", object_get_typename(OBJECT(dev)));
@@ -192,6 +203,8 @@ static void acpi_ged_send_event(AcpiDeviceIf *adev, AcpiEventStatusBits ev)
         sel = ACPI_GED_MEM_HOTPLUG_EVT;
     } else if (ev & ACPI_POWER_DOWN_STATUS) {
         sel = ACPI_GED_PWR_DOWN_EVT;
+    } else if (ev & ACPI_NVDIMM_HOTPLUG_STATUS) {
+        sel = ACPI_GED_NVDIMM_HOTPLUG_EVT;
     } else {
         /* Unknown event. Return without generating interrupt. */
         warn_report("GED: Unsupported event %d. No irq injected", ev);

hw/arm/virt.c

@@ -568,6 +568,10 @@ static inline DeviceState *create_acpi_ged(VirtMachineState *vms)
         event |= ACPI_GED_MEM_HOTPLUG_EVT;
     }
 
+    if (ms->nvdimms_state->is_enabled) {
+        event |= ACPI_GED_NVDIMM_HOTPLUG_EVT;
+    }
+
     dev = qdev_create(NULL, TYPE_ACPI_GED);
     qdev_prop_set_uint32(dev, "ged-event", event);
 
@@ -2088,19 +2092,20 @@ static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
                                  Error **errp)
 {
     VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
+    const MachineState *ms = MACHINE(hotplug_dev);
     const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
 
-    if (is_nvdimm) {
-        error_setg(errp, "nvdimm is not yet supported");
-        return;
-    }
-
     if (!vms->acpi_dev) {
         error_setg(errp,
                    "memory hotplug is not enabled: missing acpi-ged device");
         return;
     }
 
+    if (is_nvdimm && !ms->nvdimms_state->is_enabled) {
+        error_setg(errp, "nvdimm is not enabled: add 'nvdimm=on' to '-M'");
+        return;
+    }
+
     pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), NULL, errp);
 }
 
@@ -2245,6 +2250,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
     hc->plug = virt_machine_device_plug_cb;
     hc->unplug_request = virt_machine_device_unplug_request_cb;
     mc->numa_mem_supported = true;
+    mc->nvdimm_supported = true;
     mc->auto_enable_numa_with_memhp = true;
     mc->default_ram_id = "mach-virt.ram";
 

include/hw/acpi/generic_event_device.h

@@ -82,6 +82,7 @@
  */
 #define ACPI_GED_MEM_HOTPLUG_EVT   0x1
 #define ACPI_GED_PWR_DOWN_EVT      0x2
+#define ACPI_GED_NVDIMM_HOTPLUG_EVT 0x4
 
 typedef struct GEDState {
     MemoryRegion io;