Fix mask, adapt macros.rs to use current patterns

Author: KushalMeghani1644

riscv/src/register/macros.rs

@@ -1042,15 +1042,9 @@ macro_rules! test_csr_field {
     }};
 
     // test a multi-bit bitfield for read-only CSR (must come before enum pattern)
-    ($reg:ident, $field:ident: [$start:literal, $end:literal]) => {{
+    ($reg:ident, $field:ident: [$start:expr, $end:expr]) => {{
         let bits = $reg.bits();
-
-        let shift = $end - $start + 1;
-        let mask = (1usize << shift) - 1;
-
-        let exp_val = (bits >> $start) & mask;
-
-        // Test field extraction matches expected value
+        let exp_val = $crate::bits::bf_extract(bits, $start, $end - $start + 1);
         assert_eq!($reg.$field(), exp_val);
     }};
 

riscv/src/register/mtopi.rs

@@ -24,7 +24,7 @@
 read_only_csr! {
     /// Machine Top Priority Interrupt Register
     Mtopi: 0x7C0,
-    mask: 0x0FFF_FFFF,
+    mask: 0x0FFF_00FF,
 }
 
 read_only_csr_field! {