[Qemu-devel] [PATCH v6 5/8] 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>
---
v4-->v5

 -Removed gsi/ged-irq routing instead set irq directly.
 -Create GED only for ACPI case

---
 hw/arm/Kconfig           |  2 ++
 hw/arm/virt-acpi-build.c | 14 ++++++++++++
 hw/arm/virt.c            | 48 ++++++++++++++++++++++++++++++++++------
 include/hw/arm/virt.h    |  3 +++
 4 files changed, 60 insertions(+), 7 deletions(-)

diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index 05c329f1e9..d75634c4ef 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 d216c7f892..51173f6ce1 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 */
@@ -519,6 +523,25 @@ 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();
@@ -1691,6 +1714,10 @@ static void machvirt_init(MachineState *machine)
 
     create_gpio(vms, pic);
 
+    if (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.
@@ -1869,27 +1896,34 @@ 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,
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index a72094204e..d5a7d299b9 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,
 };
 
@@ -133,6 +135,7 @@ 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