[v3,7/7] Update the ACPI table for the Loongarch CPU

diff --git a/hw/acpi/acpi-cpu-hotplug-stub.c b/hw/acpi/acpi-cpu-hotplug-stub.c
index 2aec90d968..b3ac7a1e31 100644
--- a/hw/acpi/acpi-cpu-hotplug-stub.c
+++ b/hw/acpi/acpi-cpu-hotplug-stub.c
@@ -19,6 +19,15 @@  void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
     return;
 }
 
+void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
+                    build_madt_cpu_fn build_madt_cpu, hwaddr mmap_io_base,
+                    const char *res_root,
+                    const char *event_handler_method,
+                    AmlRegionSpace rs)
+{
+    return;
+}
+
 void acpi_cpu_ospm_status(CPUHotplugState *cpu_st, ACPIOSTInfoList ***list)
 {
     return;
diff --git a/hw/loongarch/acpi-build.c b/hw/loongarch/acpi-build.c
index ae292fc543..cf89e5c1cb 100644
--- a/hw/loongarch/acpi-build.c
+++ b/hw/loongarch/acpi-build.c
@@ -46,6 +46,23 @@ 
 #define ACPI_BUILD_DPRINTF(fmt, ...)
 #endif
 
+static void virt_madt_cpu_entry(int uid,
+                                const CPUArchIdList *apic_ids,
+                                GArray *entry, bool force_enabled)
+{
+    uint32_t apic_id = apic_ids->cpus[uid].arch_id;
+    /* Flags – Local APIC Flags */
+    uint32_t flags = apic_ids->cpus[uid].cpu != NULL || force_enabled ?
+                     1 /* Enabled */ : 0;
+
+    /* Rev 1.0b, Table 5-13 Processor Local APIC Structure */
+    build_append_int_noprefix(entry, 0, 1);       /* Type */
+    build_append_int_noprefix(entry, 8, 1);       /* Length */
+    build_append_int_noprefix(entry, uid, 1);     /* ACPI Processor ID */
+    build_append_int_noprefix(entry, apic_id, 1); /* APIC ID */
+    build_append_int_noprefix(entry, flags, 4); /* Flags */
+}
+
 /* build FADT */
 static void init_common_fadt_data(AcpiFadtData *data)
 {
@@ -121,15 +138,18 @@  build_madt(GArray *table_data, BIOSLinker *linker, LoongArchMachineState *lams)
     build_append_int_noprefix(table_data, 1 /* PCAT_COMPAT */, 4); /* Flags */
 
     for (i = 0; i < arch_ids->len; i++) {
+        uint32_t flags;
+
         /* Processor Core Interrupt Controller Structure */
         arch_id = arch_ids->cpus[i].arch_id;
+        flags = arch_ids->cpus[i].cpu ? 1 : 0;
 
         build_append_int_noprefix(table_data, 17, 1);    /* Type */
         build_append_int_noprefix(table_data, 15, 1);    /* Length */
         build_append_int_noprefix(table_data, 1, 1);     /* Version */
         build_append_int_noprefix(table_data, i, 4);     /* ACPI Processor ID */
         build_append_int_noprefix(table_data, arch_id, 4); /* Core ID */
-        build_append_int_noprefix(table_data, 1, 4);     /* Flags */
+        build_append_int_noprefix(table_data, flags, 4);   /* Flags */
     }
 
     /* Extend I/O Interrupt Controller Structure */
@@ -292,6 +312,18 @@  build_la_ged_aml(Aml *dsdt, MachineState *machine)
                                  AML_SYSTEM_MEMORY,
                                  VIRT_GED_MEM_ADDR);
     }
+
+    if (event & ACPI_GED_CPU_HOTPLUG_EVT) {
+        CPUHotplugFeatures opts = {
+            .acpi_1_compatible = false,
+            .has_legacy_cphp = false
+        };
+
+        build_cpus_aml(dsdt, machine, opts, virt_madt_cpu_entry,
+                       VIRT_GED_CPUHP_ADDR, "\\_SB", "\\_GPE._E01",
+                       AML_SYSTEM_MEMORY);
+
+    }
     acpi_dsdt_add_power_button(dsdt);
 }
 
diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index c704f3117f..22b287eb39 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -449,7 +449,7 @@  static DeviceState *create_acpi_ged(DeviceState *pch_pic, LoongArchMachineState
 {
     DeviceState *dev;
     MachineState *ms = MACHINE(lams);
-    uint32_t event = ACPI_GED_PWR_DOWN_EVT;
+    uint32_t event = ACPI_GED_PWR_DOWN_EVT | ACPI_GED_CPU_HOTPLUG_EVT;
 
     if (ms->ram_slots) {
         event |= ACPI_GED_MEM_HOTPLUG_EVT;
@@ -463,6 +463,7 @@  static DeviceState *create_acpi_ged(DeviceState *pch_pic, LoongArchMachineState
     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, VIRT_GED_MEM_ADDR);
     /* ged regs used for reset and power down */
     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 2, VIRT_GED_REG_ADDR);
+    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 3, VIRT_GED_CPUHP_ADDR);
 
     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0,
                        qdev_get_gpio_in(pch_pic, VIRT_SCI_IRQ - VIRT_GSI_BASE));
diff --git a/include/hw/loongarch/virt.h b/include/hw/loongarch/virt.h
index 176dc43a93..e23a45f9bb 100644
--- a/include/hw/loongarch/virt.h
+++ b/include/hw/loongarch/virt.h
@@ -31,6 +31,7 @@ 
 #define VIRT_GED_EVT_ADDR       0x100e0000
 #define VIRT_GED_MEM_ADDR       (VIRT_GED_EVT_ADDR + ACPI_GED_EVT_SEL_LEN)
 #define VIRT_GED_REG_ADDR       (VIRT_GED_MEM_ADDR + MEMORY_HOTPLUG_IO_LEN)
+#define VIRT_GED_CPUHP_ADDR     (VIRT_GED_REG_ADDR + ACPI_CPU_HOTPLUG_REG_LEN)
 
 struct LoongArchMachineState {
     /*< private >*/