Generate additional DSDT description for ACPI PCI hotplug
support.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 include/hw/arm/virt.h    |  1 +
 hw/arm/virt-acpi-build.c | 24 ++++++++++++++++++++++++
 hw/arm/virt.c            |  1 +
 hw/arm/Kconfig           |  2 ++
 4 files changed, 28 insertions(+)

diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 1e9d002880..b8ca753644 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -79,6 +79,7 @@ enum {
     VIRT_ACPI_GED,
     VIRT_NVDIMM_ACPI,
     VIRT_PVTIME,
+    VIRT_ACPI_PCIHP,
     VIRT_LOWMEMMAP_LAST,
 };
 
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 46c5a43d27..7bee57d489 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -34,6 +34,7 @@
 #include "hw/core/cpu.h"
 #include "hw/acpi/acpi-defs.h"
 #include "hw/acpi/acpi.h"
+#include "hw/acpi/pcihp.h"
 #include "hw/nvram/fw_cfg_acpi.h"
 #include "hw/acpi/bios-linker-loader.h"
 #include "hw/acpi/aml-build.h"
@@ -840,6 +841,29 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
                          (irqmap[VIRT_MMIO] + ARM_SPI_BASE),
                          0, NUM_VIRTIO_TRANSPORTS);
     acpi_dsdt_add_pci(scope, memmap, irqmap[VIRT_PCIE] + ARM_SPI_BASE, vms);
+
+    aml_append(dsdt, scope);
+
+    if (vms->acpi_pcihp) {
+        Aml *pci0_scope = aml_scope("\\_SB.PCI0");
+
+        build_acpi_pci_hotplug(dsdt, AML_SYSTEM_MEMORY,
+                               memmap[VIRT_ACPI_PCIHP].base);
+        build_append_pcihp_resources(pci0_scope,
+                                     memmap[VIRT_ACPI_PCIHP].base,
+                                     memmap[VIRT_ACPI_PCIHP].size);
+
+        /* Scan all PCI buses. Generate tables to support hotplug. */
+        build_append_pci_bus_devices(pci0_scope, vms->bus);
+        if (object_property_find(OBJECT(vms->bus), ACPI_PCIHP_PROP_BSEL)) {
+            build_append_pcihp_slots(pci0_scope, vms->bus);
+        }
+        build_append_notification_callback(pci0_scope, vms->bus);
+        aml_append(dsdt, pci0_scope);
+    }
+
+    scope = aml_scope("\\_SB");
+
     if (vms->acpi_dev) {
         build_ged_aml(scope, "\\_SB."GED_DEVICE,
                       HOTPLUG_HANDLER(vms->acpi_dev),
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 1601750913..2790853927 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -183,6 +183,7 @@ static const MemMapEntry base_memmap[] = {
     [VIRT_NVDIMM_ACPI] =        { 0x09090000, NVDIMM_ACPI_IO_LEN},
     [VIRT_PVTIME] =             { 0x090a0000, 0x00010000 },
     [VIRT_SECURE_GPIO] =        { 0x090b0000, 0x00001000 },
+    [VIRT_ACPI_PCIHP] =         { 0x090c0000, 0x00001000 },
     [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
     /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */
     [VIRT_PLATFORM_BUS] =       { 0x0c000000, 0x02000000 },
diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index a55b44d7bd..572b4dabd5 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -34,6 +34,8 @@ config ARM_VIRT
     select ACPI_HW_REDUCED
     select ACPI_APEI
     select ACPI_VIOT
+    select ACPI_PCIHP
+    select ACPI_PCI_BRIDGE
     select VIRTIO_MEM_SUPPORTED
     select ACPI_CXL
     select ACPI_HMAT
-- 
2.49.0