Implement DelayNs for McycleDelay

riscv/src/delay.rs

@@ -1,6 +1,6 @@
 //! Delay devices and providers
 use crate::register::mcycle;
-use embedded_hal::delay::DelayUs;
+use embedded_hal::delay::DelayNs;
 
 /// Machine mode cycle counter (`mcycle`) as a delay provider
 #[derive(Copy, Clone)]
@@ -19,12 +19,17 @@ impl McycleDelay {
     }
 }
 
-impl DelayUs for McycleDelay {
+impl DelayNs for McycleDelay {
     #[inline]
     fn delay_us(&mut self, us: u32) {
+	self.delay_ns(us * 1000)
+    }
+
+    #[inline]
+   fn delay_ns(&mut self, ns: u32) {
         let t0 = mcycle::read64();
-        let us_64: u64 = us.into();
-        let clock = (us_64 * (self.ticks_second as u64)) / 1_000_000u64;
+        let us_64: u64 = ns.into();
+        let clock = (us_64 * (self.ticks_second as u64)) / 1_000_000_000u64;
         while mcycle::read64().wrapping_sub(t0) <= clock {}
-    }
+   }
 }