Make Uart::write slightly more conventional

examples/headsail-bsp/examples/uart0.rs

@@ -7,6 +7,6 @@ use headsail_bsp::{apb_uart::ApbUart0, rt::entry};
 fn main() -> ! {
     let (soc_freq, baud) = (30_000_000, 115_200);
     let mut uart = ApbUart0::init(soc_freq, baud);
-    uart.write("Hello world!");
+    uart.write_str("Hello world!");
     loop {}
 }

examples/headsail-bsp/src/apb_uart.rs

@@ -77,12 +77,26 @@ impl<const BASE_ADDR: usize> ApbUart<BASE_ADDR> {
     }
 
     #[inline]
-    pub fn write(&mut self, s: &str) {
-        for b in s.as_bytes() {
+    pub fn write(&mut self, buf: &[u8]) {
+        for b in buf {
             self.putc(*b);
         }
     }
 
+    #[inline]
+    pub fn write_str(&mut self, s: &str) {
+        self.write(s.as_bytes());
+    }
+
+    /// Flush this output stream, blocking until all intermediately buffered contents reach their
+    /// destination.
+    #[inline]
+    pub fn flush(&mut self) {
+        // Wait for hardware to report completion
+        #[cfg(feature = "asic")]
+        while !self.is_transmit_empty() {}
+    }
+
     #[inline]
     pub fn putc(&mut self, c: u8) {
         // Wait for hardware to report completion

examples/headsail-bsp/src/sprintln.rs

@@ -32,7 +32,7 @@ impl ufmt::uWrite for ApbUart0 {
     type Error = core::convert::Infallible;
 
     fn write_str(&mut self, s: &str) -> Result<(), Self::Error> {
-        self.write(s);
+        self.write_str(s);
         Ok(())
     }
 }

examples/headsail-bsp/src/tb.rs

@@ -10,15 +10,15 @@ pub const TAG_OK: &str = "[OK]";
 
 pub fn report_pass() {
     let mut uart = unsafe { ApbUart0::instance() };
-    uart.write(TAG_PASS);
+    uart.write_str(TAG_PASS);
 }
 
 pub fn report_fail() {
     let mut uart = unsafe { ApbUart0::instance() };
-    uart.write(TAG_FAIL);
+    uart.write_str(TAG_FAIL);
 }
 
 pub fn report_ok() {
     let mut uart = unsafe { ApbUart0::instance() };
-    uart.write(TAG_OK);
+    uart.write_str(TAG_OK);
 }