arm: async uart writes & fixes

arm/main.cc

@@ -10,14 +10,9 @@
 namespace {
 using async::AwaitableType;
 
-void HandleUartRxFromIsr(void*, unsigned int) {
-    tracing::trace(tracing::TraceEvent::kUartRxCb);
-    async::resume(AwaitableType::kUartRx);
-}
-
 void Uart0Isr() {
     tracing::trace(tracing::TraceEvent::kUartIsr);
-    XUartLite_InterruptHandler(uart0);
+    HandleUartIsr();
 }
 
 void Timer0Isr() {
@@ -36,10 +31,6 @@ void SetupUart() {
     vector_table[16 + Timer0_IRQn] = reinterpret_cast<uint32_t>(Timer0Isr);
     NVIC_SetPriority(Uart0_IRQn, 3);
     NVIC_EnableIRQ(Uart0_IRQn);
-
-    XUartLite_SetSendHandler(uart0, HandleUartTxFromIsr, nullptr);
-    XUartLite_SetRecvHandler(uart0, HandleUartRxFromIsr, nullptr);
-    XUartLite_EnableInterrupt(uart0);
 }
 
 void SetupTimer() {
@@ -49,20 +40,10 @@ void SetupTimer() {
 }
 }  // namespace
 
-async::task<buffer> UartRead(int size) {
-    auto buff = buffer::make(size);
-    auto* data = reinterpret_cast<uint8_t*>(buff.data.data());
-    size_t received = XUartLite_Recv(uart0, data, buff.data.size());
-    if (received < buff.data.size()) {
-        co_await async::await(AwaitableType::kUartRx);
-    }
-    co_return buff;
-}
-
 async::task<> echo() {
     while (1) {
         buffer buff = co_await UartRead(1);
-        UartSend(buff.data);
+        co_await UartWrite(buff.data);
     }
 }