arm: separate async stuff from main uart

arm/main.cc

@@ -6,6 +6,7 @@
 #include "timer.h"
 #include "trace.h"
 #include "uart.h"
+#include "uart_async.h"
 
 namespace {
 using async::AwaitableType;
@@ -38,7 +39,6 @@ void SetupTimer() {
     timer0->SetupAsWdt(100000 * 4000);
     timer0->EnableT1();
 }
-}  // namespace
 
 async::task<> echo() {
     while (1) {
@@ -46,6 +46,7 @@ async::task<> echo() {
         co_await UartWrite(buff.data);
     }
 }
+}  // namespace
 
 int main() {
     SetupUart();

arm/uart.cc

@@ -1,4 +1,5 @@
 #include "uart.h"
+#include "uart_async.h"
 
 #include "async.h"
 #include "gpio.h"

arm/uart.h

@@ -3,17 +3,8 @@
 #include <span>
 #include <string_view>
 
-#include "async.h"
-#include "buffer.h"
-
 void InitUarts();
 
-async::task<buffer> UartRead(int size);
-async::task<> UartWrite(std::span<const std::byte> data);
-inline async::task<> UartWrite(std::string_view s) {
-    co_await UartWrite(std::as_bytes(std::span{s.data(), s.size()}));
-}
-
 // block until the provided buffer is full
 void UartReadBlocking(std::span<std::byte> data);
 inline uint8_t UartReadByteBlocking() {

arm/uart_async.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <span>
+#include <string_view>
+
+#include "async.h"
+#include "buffer.h"
+
+async::task<buffer> UartRead(int size);
+async::task<> UartWrite(std::span<const std::byte> data);
+inline async::task<> UartWrite(std::string_view s) {
+    co_await UartWrite(std::as_bytes(std::span{s.data(), s.size()}));
+}