[USART] Call Miosix IRQ handlers instead of accessing driver implementation details

In order to reduce the number of patches we make to the Miosix kernel, we're moving to calling Miosix USART IRQ handlers instead of accessing static port objects directly, which would require marking them for external linkage.
With this commit we are dropping support for USART ports higher than 3 when using the Miosix USART driver. For higher port counts, the boardcore driver must be used.

src/shared/drivers/usart/USART.cpp

@@ -36,6 +36,11 @@
 Boardcore::USART *ports[N_USART_PORTS];
 
 #ifdef USART1
+/**
+ * \internal interrupt routine for usart1 miosix implementation
+ */
+void usart1irqImpl();
+
 /**
  * \internal Interrupt routine for usart1 actual implementation.
  */
@@ -43,12 +48,12 @@ void __attribute__((used)) usart1irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[0];
     if (port_boardcore)
+    {
         port_boardcore->IRQhandleInterrupt();
+    }
     else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[0];
-        if (port)
-            port->IRQhandleInterrupt();
+        usart1irqImpl();
     }
 }
 
@@ -64,6 +69,11 @@ void __attribute__((naked, used)) USART1_IRQHandler()
 #endif
 
 #ifdef USART2
+/**
+ * \internal interrupt routine for usart2 miosix implementation
+ */
+void usart2irqImpl();
+
 /**
  * \internal Interrupt routine for usart2 actual implementation.
  */
@@ -71,12 +81,12 @@ void __attribute__((used)) usart2irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[1];
     if (port_boardcore)
+    {
         port_boardcore->IRQhandleInterrupt();
+    }
     else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[1];
-        if (port)
-            port->IRQhandleInterrupt();
+        usart2irqImpl();
     }
 }
 
@@ -92,6 +102,11 @@ void __attribute__((naked, used)) USART2_IRQHandler()
 #endif
 
 #ifdef USART3
+/**
+ * \internal interrupt routine for usart3 miosix implementation
+ */
+void usart3irqImpl();
+
 /**
  * \internal Interrupt routine for usart3 actual implementation.
  */
@@ -99,12 +114,12 @@ void __attribute__((used)) usart3irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[2];
     if (port_boardcore)
+    {
         port_boardcore->IRQhandleInterrupt();
+    }
     else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[2];
-        if (port)
-            port->IRQhandleInterrupt();
+        usart3irqImpl();
     }
 }
 
@@ -127,12 +142,8 @@ void __attribute__((used)) uart4irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[3];
     if (port_boardcore)
-        port_boardcore->IRQhandleInterrupt();
-    else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[3];
-        if (port)
-            port->IRQhandleInterrupt();
+        port_boardcore->IRQhandleInterrupt();
     }
 }
 
@@ -155,12 +166,8 @@ void __attribute__((used)) uart5irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[4];
     if (port_boardcore)
-        port_boardcore->IRQhandleInterrupt();
-    else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[4];
-        if (port)
-            port->IRQhandleInterrupt();
+        port_boardcore->IRQhandleInterrupt();
     }
 }
 
@@ -183,12 +190,8 @@ void __attribute__((used)) usart6irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[5];
     if (port_boardcore)
-        port_boardcore->IRQhandleInterrupt();
-    else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[5];
-        if (port)
-            port->IRQhandleInterrupt();
+        port_boardcore->IRQhandleInterrupt();
     }
 }
 
@@ -211,12 +214,8 @@ void __attribute__((used)) uart7irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[6];
     if (port_boardcore)
-        port_boardcore->IRQhandleInterrupt();
-    else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[6];
-        if (port)
-            port->IRQhandleInterrupt();
+        port_boardcore->IRQhandleInterrupt();
     }
 }
 
@@ -239,12 +238,8 @@ void __attribute__((used)) uart8irqImplBoardcore()
 {
     Boardcore::USART *port_boardcore = ports[7];
     if (port_boardcore)
-        port_boardcore->IRQhandleInterrupt();
-    else
     {
-        miosix::STM32Serial *port = miosix::STM32Serial::ports[7];
-        if (port)
-            port->IRQhandleInterrupt();
+        port_boardcore->IRQhandleInterrupt();
     }
 }