Update the CPUs AML code to reflect the ACPI CPU Hotplug `is_enabled`
state in the `_STA.Enabled` Bit when the ACPI `_STA` method is evaluated
by the Guest Kernel during initialization, as well as when vCPUs are
hot-plugged or hot-unplugged.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Reviewed-by: Gustavo Romero <gustavo.romero@linaro.org>
---
 hw/acpi/cpu.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c
index 8940687f90..017b847815 100644
--- a/hw/acpi/cpu.c
+++ b/hw/acpi/cpu.c
@@ -63,7 +63,7 @@ static uint64_t cpu_hotplug_rd(void *opaque, hwaddr addr, unsigned size)
     cdev = &cpu_st->devs[cpu_st->selector];
     switch (addr) {
     case ACPI_CPU_FLAGS_OFFSET_RW: /* pack and return is_* fields */
-        val |= cdev->cpu ? 1 : 0;
+        val |= cdev->is_enabled ? 1 : 0;
         val |= cdev->is_inserting ? 2 : 0;
         val |= cdev->is_removing  ? 4 : 0;
         val |= cdev->fw_remove  ? 16 : 0;
@@ -463,15 +463,23 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
         {
             Aml *idx = aml_arg(0);
             Aml *sta = aml_local(0);
+            Aml *else_ctx;
 
             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
             aml_append(method, aml_store(idx, cpu_selector));
             aml_append(method, aml_store(zero, sta));
             ifctx = aml_if(aml_equal(is_enabled, one));
             {
+                /* cpu is present and enabled */
                 aml_append(ifctx, aml_store(aml_int(0xF), sta));
             }
             aml_append(method, ifctx);
+            else_ctx = aml_else();
+            {
+                /* cpu is present but disabled */
+                aml_append(else_ctx, aml_store(aml_int(0xD), sta));
+            }
+            aml_append(method, else_ctx);
             aml_append(method, aml_release(ctrl_lock));
             aml_append(method, aml_return(sta));
         }
-- 
2.34.1