From 409fa59e2e704ceee7a329a57c8299ffadc6363f Mon Sep 17 00:00:00 2001
From: Marco Scholl <develop@marco-scholl.de>
Date: Sat, 16 Mar 2024 07:53:47 +0100
Subject: [PATCH] wip

---
 src/rp2040_arduino_platform.cpp | 37 ++++++++++++++++++++++++++-------
 1 file changed, 29 insertions(+), 8 deletions(-)

diff --git a/src/rp2040_arduino_platform.cpp b/src/rp2040_arduino_platform.cpp
index 22fe9326..97d0be01 100644
--- a/src/rp2040_arduino_platform.cpp
+++ b/src/rp2040_arduino_platform.cpp
@@ -48,7 +48,6 @@ volatile uint8_t __attribute__((aligned(uartDmaBufferSize))) uartDmaBuffer[uartD
 volatile uint32_t uartDmaReadCount = 0;
 volatile uint16_t uartDmaRestartCount = 0;
 
-
 // Liefert die Zahl der gelesenen Bytes seit dem DMA Transferstart
 inline uint32_t uartDmaWriteCount()
 {
@@ -56,7 +55,7 @@ inline uint32_t uartDmaWriteCount()
 }
 
 // Liefert die aktuelle Schreibposition im DMA Buffer
-inline uint16_t uartDmaWritePosition()
+inline uint16_t uartDmaWriteBufferPosition()
 {
     return uartDmaWriteCount() % uartDmaBufferSize;
 }
@@ -77,7 +76,7 @@ inline uint8_t* uartDmaReadAddr()
 void __time_critical_func(uartDmaRestart)()
 {
     // println("Restart");
-    uartDmaRestartCount = uartDmaWritePosition() - uartDmaReadBufferPosition();
+    uartDmaRestartCount = uartDmaWriteBufferPosition() - uartDmaReadBufferPosition();
 
     // wenn uartDmaRestartCount == 0 ist, wurde alles verarbeitet und der read count kann mit dem neustart wieder auf 0 gesetzt werden.
     if (uartDmaRestartCount == 0)
@@ -148,11 +147,27 @@ void RP2040ArduinoPlatform::knxUartPins(pin_size_t rxPin, pin_size_t txPin)
 bool RP2040ArduinoPlatform::overflowUart()
 {
 #ifdef KNX_USE_DMA_UART0
-    // during dma restart overflow not detectable
-    if (uartDmaRestartCount > 0 || uartDmaWriteCount() == 0)
-        return false;
-
-    return (uartDmaWriteCount() - uartDmaReadCount) > uartDmaBufferSize;
+    // during dma restart
+    bool ret;
+    const uint32_t writeCount = uartDmaWriteCount();
+    if (uartDmaRestartCount > 0)
+        ret = writeCount >= (uartDmaBufferSize - uartDmaRestartCount - 1);
+    else
+        ret = (writeCount - uartDmaReadCount) > uartDmaBufferSize;
+
+    // if (ret)
+    // {
+    //     println(uartDmaWriteBufferPosition());
+    //     println(uartDmaReadBufferPosition());
+    //     println(uartDmaWriteCount());
+    //     println(uartDmaReadCount);
+    //     println(uartDmaRestartCount);
+    //     printHex("BUF: ", (const uint8_t *)uartDmaBuffer, uartDmaBufferSize);
+    //     println("OVERFLOW");
+    //     while (true)
+    //         ;
+    // }
+    return ret;
 #else
     SerialUART* serial = dynamic_cast<SerialUART*>(_knxSerial);
     return serial->overflow();
@@ -210,6 +225,9 @@ void RP2040ArduinoPlatform::setupUart()
 #ifdef KNX_USE_DMA_UART0
 int RP2040ArduinoPlatform::uartAvailable()
 {
+    if (uartDmaChannel == -1)
+        return 0;
+
     if (uartDmaRestartCount > 0)
     {
         return uartDmaRestartCount;
@@ -256,6 +274,9 @@ int RP2040ArduinoPlatform::readUart()
 
 size_t RP2040ArduinoPlatform::writeUart(const uint8_t data)
 {
+    if (uartDmaChannel == -1)
+        return 0;
+
     // print("> ");
     // println(data, HEX);
     while (!uart_is_writable(uart0))