acpi: add aml_debug()

Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NMarcel Apfelbaum <marcel@redhat.com>

hw/acpi/aml-build.c

@@ -406,6 +406,15 @@ Aml *aml_return(Aml *val)
     return var;
 }
 
+/* ACPI 1.0b: 16.2.6.3 Debug Objects Encoding: DebugObj */
+Aml *aml_debug(void)
+{
+    Aml *var = aml_alloc();
+    build_append_byte(var->buf, 0x5B); /* ExtOpPrefix */
+    build_append_byte(var->buf, 0x31); /* DebugOp */
+    return var;
+}
+
 /*
  * ACPI 1.0b: 16.2.3 Data Objects Encoding:
  * encodes: ByteConst, WordConst, DWordConst, QWordConst, ZeroOp, OneOp

include/hw/acpi/aml-build.h

@@ -252,6 +252,7 @@ void aml_append(Aml *parent_ctx, Aml *child);
 /* non block AML object primitives */
 Aml *aml_name(const char *name_format, ...) GCC_FMT_ATTR(1, 2);
 Aml *aml_name_decl(const char *name, Aml *val);
+Aml *aml_debug(void);
 Aml *aml_return(Aml *val);
 Aml *aml_int(const uint64_t val);
 Aml *aml_arg(int pos);