riscv: extend CSR test macro for ranges

Extends the CSR test helper macro to handle range bit fields.

Author: rmsyn

riscv/src/register/macros.rs

@@ -1063,6 +1063,7 @@ macro_rules! write_only_csr_field {
 #[cfg(test)]
 #[macro_export]
 macro_rules! test_csr_field {
+    // test a single bit field
     ($reg:ident, $field:ident) => {{
         $crate::paste! {
             assert!(!$reg.$field());
@@ -1074,4 +1075,20 @@ macro_rules! test_csr_field {
             assert!(!$reg.$field());
         }
     }};
+
+    // test a range bit field
+    ($reg:ident, $field:ident, $index:expr) => {{
+        $crate::paste! {
+            assert!(!$reg.$field($index));
+            assert_eq!($reg.[<try_ $field>]($index), Ok(false));
+
+            $reg.[<set_ $field>]($index, true);
+            assert!($reg.$field($index));
+
+            assert_eq!($reg.[<try_set_ $field>]($index, false), Ok(()));
+            assert_eq!($reg.[<try_ $field>]($index), Ok(false));
+
+            assert!(!$reg.$field($index));
+        }
+    }};
 }