diff --git a/tools/generate_constants_json.py b/tools/generate_constants_json.py
index 3fe8684..005fff8 100755
--- a/tools/generate_constants_json.py
+++ b/tools/generate_constants_json.py
@@ -130,6 +130,8 @@
         constants_json['arch_name'] = 'arm64'
     elif constants_json['arch_nr'] == 0x40000028:
         constants_json['arch_name'] = 'arm'
+    elif constants_json['arch_nr'] == 0xC00000F3:
+        constants_json['arch_name'] = 'riscv64'
     else:
         raise ValueError('Unknown architecture: 0x%08X' %
                          constants_json['arch_nr'])