[Qemu-devel] [PATCH-for-4.2 v7 06/10] hw/arm/virt: Enable device memory cold/hot plug with ACPI boot

[Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>]

This initializes the GED device with base memory and irq, configures
ged memory hotplug event and builds the corresponding aml code. With
this, both hot and cold plug of device memory is enabled now for Guest
with ACPI boot.

Memory cold plug support with Guest DT boot is not yet supported.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
v6 --> v7
  Disabled ACPI GED dev creation for machine < 4.2.

---
 hw/arm/Kconfig           |  2 ++
 hw/arm/virt-acpi-build.c | 14 +++++++++++
 hw/arm/virt.c            | 51 ++++++++++++++++++++++++++++++++++------
 include/hw/arm/virt.h    |  4 ++++
 4 files changed, 64 insertions(+), 7 deletions(-)

diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index 84961c17ab..ad7f7c089b 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -22,6 +22,8 @@ config ARM_VIRT
     select ACPI_PCI
     select MEM_DEVICE
     select DIMM
+    select ACPI_MEMORY_HOTPLUG
+    select ACPI_HW_REDUCED
 
 config CHEETAH
     bool
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 0afb372769..018b1e326d 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -40,6 +40,8 @@
 #include "hw/acpi/aml-build.h"
 #include "hw/acpi/utils.h"
 #include "hw/acpi/pci.h"
+#include "hw/acpi/memory_hotplug.h"
+#include "hw/acpi/generic_event_device.h"
 #include "hw/pci/pcie_host.h"
 #include "hw/pci/pci.h"
 #include "hw/arm/virt.h"
@@ -705,6 +707,7 @@ static void
 build_dsdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
 {
     Aml *scope, *dsdt;
+    MachineState *ms = MACHINE(vms);
     const MemMapEntry *memmap = vms->memmap;
     const int *irqmap = vms->irqmap;
 
@@ -729,6 +732,17 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
                       vms->highmem, vms->highmem_ecam);
     acpi_dsdt_add_gpio(scope, &memmap[VIRT_GPIO],
                        (irqmap[VIRT_GPIO] + ARM_SPI_BASE));
+    if (vms->acpi_dev) {
+        build_ged_aml(scope, "\\_SB."GED_DEVICE,
+                      HOTPLUG_HANDLER(vms->acpi_dev),
+                      irqmap[VIRT_ACPI_GED] + ARM_SPI_BASE, AML_SYSTEM_MEMORY);
+    }
+
+    if (vms->acpi_dev && ms->ram_slots) {
+        build_memory_hotplug_aml(scope, ms->ram_slots, "\\_SB", NULL,
+                                 AML_SYSTEM_MEMORY);
+    }
+
     acpi_dsdt_add_power_button(scope);
 
     aml_append(dsdt, scope);
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index bbe156dc35..ffcccc05ad 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -66,6 +66,7 @@
 #include "target/arm/internals.h"
 #include "hw/mem/pc-dimm.h"
 #include "hw/mem/nvdimm.h"
+#include "hw/acpi/generic_event_device.h"
 
 #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
     static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
@@ -136,6 +137,8 @@ static const MemMapEntry base_memmap[] = {
     [VIRT_GPIO] =               { 0x09030000, 0x00001000 },
     [VIRT_SECURE_UART] =        { 0x09040000, 0x00001000 },
     [VIRT_SMMU] =               { 0x09050000, 0x00020000 },
+    [VIRT_PCDIMM_ACPI] =        { 0x09070000, MEMORY_HOTPLUG_IO_LEN },
+    [VIRT_ACPI_GED] =           { 0x09080000, ACPI_GED_REG_LEN },
     [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
     /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */
     [VIRT_PLATFORM_BUS] =       { 0x0c000000, 0x02000000 },
@@ -171,6 +174,7 @@ static const int a15irqmap[] = {
     [VIRT_PCIE] = 3, /* ... to 6 */
     [VIRT_GPIO] = 7,
     [VIRT_SECURE_UART] = 8,
+    [VIRT_ACPI_GED] = 9,
     [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */
     [VIRT_GIC_V2M] = 48, /* ...to 48 + NUM_GICV2M_SPIS - 1 */
     [VIRT_SMMU] = 74,    /* ...to 74 + NUM_SMMU_IRQS - 1 */
@@ -520,6 +524,25 @@ static void fdt_add_pmu_nodes(const VirtMachineState *vms)
     }
 }
 
+static inline DeviceState *create_acpi_ged(VirtMachineState *vms, qemu_irq *pic)
+{
+    DeviceState *dev;
+    int irq = vms->irqmap[VIRT_ACPI_GED];
+    uint32_t event = ACPI_GED_MEM_HOTPLUG_EVT;
+
+    dev = DEVICE(object_new(TYPE_ACPI_GED));
+    qdev_prop_set_uint64(dev, "memhp-base",
+                         vms->memmap[VIRT_PCDIMM_ACPI].base);
+    qdev_prop_set_uint64(dev, "ged-base", vms->memmap[VIRT_ACPI_GED].base);
+    qdev_prop_set_uint32(dev, "ged-event", event);
+    object_property_add_child(qdev_get_machine(), "acpi-ged",
+                              OBJECT(dev), NULL);
+    qdev_init_nofail(dev);
+    qdev_connect_gpio_out_named(dev, "ged-irq", 0, pic[irq]);
+
+    return dev;
+}
+
 static void create_its(VirtMachineState *vms, DeviceState *gicdev)
 {
     const char *itsclass = its_class_name();
@@ -1697,6 +1720,10 @@ static void machvirt_init(MachineState *machine)
 
     create_gpio(vms, pic);
 
+    if (!vmc->no_acpi_dev && aarch64 && firmware_loaded && acpi_enabled) {
+        vms->acpi_dev = create_acpi_ged(vms, pic);
+    }
+
     /* Create mmio transports, so the user can create virtio backends
      * (which will be automatically plugged in to the transports). If
      * no backend is created the transport will just sit harmlessly idle.
@@ -1876,27 +1903,34 @@ static const CPUArchIdList *virt_possible_cpu_arch_ids(MachineState *ms)
 static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
                                  Error **errp)
 {
+    VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
+    const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
 
-    /*
-     * The device memory is not yet exposed to the Guest either through
-     * DT or ACPI and hence both cold/hot plug of memory is explicitly
-     * disabled for now.
-     */
-    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
-        error_setg(errp, "memory cold/hot plug is not yet supported");
+    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 device");
+        return;
+    }
+
+    hotplug_handler_pre_plug(HOTPLUG_HANDLER(vms->acpi_dev), dev, errp);
+
     pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), NULL, errp);
 }
 
 static void virt_memory_plug(HotplugHandler *hotplug_dev,
                              DeviceState *dev, Error **errp)
 {
+    HotplugHandlerClass *hhc;
     VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
 
     pc_dimm_plug(PC_DIMM(dev), MACHINE(vms), NULL);
 
+    hhc = HOTPLUG_HANDLER_GET_CLASS(vms->acpi_dev);
+    hhc->plug(HOTPLUG_HANDLER(vms->acpi_dev), dev, NULL);
 }
 
 static void virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
@@ -2102,8 +2136,11 @@ DEFINE_VIRT_MACHINE_AS_LATEST(4, 2)
 
 static void virt_machine_4_1_options(MachineClass *mc)
 {
+    VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc));
+
     virt_machine_4_2_options(mc);
     compat_props_add(mc->compat_props, hw_compat_4_1, hw_compat_4_1_len);
+    vmc->no_acpi_dev = true;
 }
 DEFINE_VIRT_MACHINE(4, 1)
 
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index a72094204e..32892af1dd 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -77,6 +77,8 @@ enum {
     VIRT_GPIO,
     VIRT_SECURE_UART,
     VIRT_SECURE_MEM,
+    VIRT_PCDIMM_ACPI,
+    VIRT_ACPI_GED,
     VIRT_LOWMEMMAP_LAST,
 };
 
@@ -106,6 +108,7 @@ typedef struct {
     bool claim_edge_triggered_timers;
     bool smbios_old_sys_ver;
     bool no_highmem_ecam;
+    bool no_acpi_dev;
 } VirtMachineClass;
 
 typedef struct {
@@ -133,6 +136,7 @@ typedef struct {
     uint32_t iommu_phandle;
     int psci_conduit;
     hwaddr highest_gpa;
+    DeviceState *acpi_dev;
 } VirtMachineState;
 
 #define VIRT_ECAM_ID(high) (high ? VIRT_HIGH_PCIE_ECAM : VIRT_PCIE_ECAM)
-- 
2.17.1