UART DMA code refactor (#8980)

UART DMA code refactor

src/main/drivers/serial_uart.c

@@ -37,12 +37,62 @@
 #include "common/utils.h"
 
 #include "drivers/dma.h"
+#include "drivers/dma_reqmap.h"
 #include "drivers/rcc.h"
-
 #include "drivers/serial.h"
 #include "drivers/serial_uart.h"
 #include "drivers/serial_uart_impl.h"
 
+#include "pg/serial_uart.h"
+
+#if defined(STM32H7)
+#define UART_BUFFER_ATTRIBUTE DMA_RAM            // D2 SRAM
+#elif defined(STM32F7)
+#define UART_BUFFER_ATTRIBUTE FAST_RAM_ZERO_INIT // DTCM RAM
+#elif defined(STM32F4) || defined(STM32F3) || defined(STM32F1)
+#define UART_BUFFER_ATTRIBUTE                    // NONE
+#else
+#error Undefined UART_BUFFER_ATTRIBUTE for this MCU
+#endif
+
+#define UART_BUFFERS(n) \
+    UART_BUFFER(UART_BUFFER_ATTRIBUTE, n, R); \
+    UART_BUFFER(UART_BUFFER_ATTRIBUTE, n, T); struct dummy_s
+
+#ifdef USE_UART1
+UART_BUFFERS(1);
+#endif
+
+#ifdef USE_UART2
+UART_BUFFERS(2);
+#endif
+
+#ifdef USE_UART3
+UART_BUFFERS(3);
+#endif
+
+#ifdef USE_UART4
+UART_BUFFERS(4);
+#endif
+
+#ifdef USE_UART5
+UART_BUFFERS(5);
+#endif
+
+#ifdef USE_UART6
+UART_BUFFERS(6);
+#endif
+
+#ifdef USE_UART7
+UART_BUFFERS(7);
+#endif
+
+#ifdef USE_UART8
+UART_BUFFERS(8);
+#endif
+
+#undef UART_BUFFERS
+
 serialPort_t *uartOpen(UARTDevice_e device, serialReceiveCallbackPtr rxCallback, void *rxCallbackData, uint32_t baudRate, portMode_e mode, portOptions_e options)
 {   
     uartPort_t *s = serialUART(device, baudRate, mode, options);
@@ -232,6 +282,60 @@ const struct serialPortVTable uartVTable[] = {
     }
 };
 
+#ifdef USE_DMA
+void uartConfigureDma(uartDevice_t *uartdev)
+{
+    uartPort_t *s = &(uartdev->port);
+    const uartHardware_t *hardware = uartdev->hardware;
+
+#ifdef USE_DMA_SPEC
+    UARTDevice_e device = hardware->device;
+    const dmaChannelSpec_t *dmaChannelSpec;
+
+    if (serialUartConfig(device)->txDmaopt != DMA_OPT_UNUSED) {
+        dmaChannelSpec = dmaGetChannelSpecByPeripheral(DMA_PERIPH_UART_TX, device, serialUartConfig(device)->txDmaopt);
+        if (dmaChannelSpec) {
+            s->txDMAResource = dmaChannelSpec->ref;
+            s->txDMAChannel = dmaChannelSpec->channel;
+        }
+    }
+
+    if (serialUartConfig(device)->rxDmaopt != DMA_OPT_UNUSED) {
+        dmaChannelSpec = dmaGetChannelSpecByPeripheral(DMA_PERIPH_UART_RX, device, serialUartConfig(device)->txDmaopt);
+        if (dmaChannelSpec) {
+            s->rxDMAResource = dmaChannelSpec->ref;
+            s->rxDMAChannel = dmaChannelSpec->channel;
+        }
+    }
+#else
+    // Non USE_DMA_SPEC does not support configurable ON/OFF of UART DMA
+
+    if (hardware->rxDMAResource) {
+        s->rxDMAResource = hardware->rxDMAResource;
+        s->rxDMAChannel = hardware->rxDMAChannel;
+    }
+
+    if (hardware->txDMAResource) {
+        s->txDMAResource = hardware->txDMAResource;
+        s->txDMAChannel = hardware->txDMAChannel;
+    }
+#endif
+
+    if (s->txDMAResource) {
+        dmaIdentifier_e identifier = dmaGetIdentifier(s->txDMAResource);
+        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(hardware->device));
+        dmaSetHandler(identifier, uartDmaIrqHandler, hardware->txPriority, (uint32_t)uartdev);
+        s->txDMAPeripheralBaseAddr = (uint32_t)&UART_REG_TXD(hardware->reg);
+    }
+
+    if (s->rxDMAResource) {
+        dmaIdentifier_e identifier = dmaGetIdentifier(s->rxDMAResource);
+        dmaInit(identifier, OWNER_SERIAL_RX, RESOURCE_INDEX(hardware->device));
+        s->rxDMAPeripheralBaseAddr = (uint32_t)&UART_REG_RXD(hardware->reg);
+    }
+}
+#endif
+
 #define UART_IRQHandler(type, dev)                            \
     void type ## dev ## _IRQHandler(void)                     \
     {                                                         \

src/main/drivers/serial_uart.h

@@ -44,9 +44,6 @@ typedef struct uartPort_s {
     serialPort_t port;
 
 #ifdef USE_DMA
-    bool rxUseDma;
-    bool txUseDma;
-
 #ifdef USE_HAL_DRIVER
     DMA_HandleTypeDef rxDMAHandle;
     DMA_HandleTypeDef txDMAHandle;
@@ -54,13 +51,8 @@ typedef struct uartPort_s {
 
     dmaResource_t *rxDMAResource;
     dmaResource_t *txDMAResource;
-#if defined(STM32F4) || defined(STM32F7)
     uint32_t rxDMAChannel;
     uint32_t txDMAChannel;
-#elif defined(STM32H7)
-    uint8_t rxDMARequest;
-    uint8_t txDMARequest;
-#endif
 
     uint32_t rxDMAIrq;
     uint32_t txDMAIrq;

src/main/drivers/serial_uart_hal.c

@@ -111,7 +111,7 @@ void uartReconfigure(uartPort_t *uartPort)
 #if !defined(STM32H7)
             uartPort->rxDMAHandle.Init.Channel = uartPort->rxDMAChannel;
 #else 
-            uartPort->txDMAHandle.Init.Request = uartPort->rxDMARequest;
+            uartPort->txDMAHandle.Init.Request = uartPort->rxDMAChannel;
 #endif
             uartPort->rxDMAHandle.Init.Direction = DMA_PERIPH_TO_MEMORY;
             uartPort->rxDMAHandle.Init.PeriphInc = DMA_PINC_DISABLE;
@@ -159,7 +159,7 @@ void uartReconfigure(uartPort_t *uartPort)
 #if !defined(STM32H7)
             uartPort->txDMAHandle.Init.Channel = uartPort->txDMAChannel;
 #else 
-            uartPort->txDMAHandle.Init.Request = uartPort->txDMARequest;
+            uartPort->txDMAHandle.Init.Request = uartPort->txDMAChannel;
 #endif
             uartPort->txDMAHandle.Init.Direction = DMA_MEMORY_TO_PERIPH;
             uartPort->txDMAHandle.Init.PeriphInc = DMA_PINC_DISABLE;
@@ -230,6 +230,100 @@ void uartTryStartTxDMA(uartPort_t *s)
         HAL_UART_Transmit_DMA(&s->Handle, (uint8_t *)&s->port.txBuffer[fromwhere], size);
     }
 }
+
+static void handleUsartTxDma(uartPort_t *s)
+{
+    uartTryStartTxDMA(s);
+}
+
+void uartDmaIrqHandler(dmaChannelDescriptor_t* descriptor)
+{
+    uartPort_t *s = &(((uartDevice_t*)(descriptor->userParam))->port);
+    HAL_DMA_IRQHandler(&s->txDMAHandle);
+}
 #endif
 
+void uartIrqHandler(uartPort_t *s)
+{
+    UART_HandleTypeDef *huart = &s->Handle;
+    /* UART in mode Receiver ---------------------------------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_RXNE) != RESET)) {
+        uint8_t rbyte = (uint8_t)(huart->Instance->RDR & (uint8_t) 0xff);
+
+        if (s->port.rxCallback) {
+            s->port.rxCallback(rbyte, s->port.rxCallbackData);
+        } else {
+            s->port.rxBuffer[s->port.rxBufferHead] = rbyte;
+            s->port.rxBufferHead = (s->port.rxBufferHead + 1) % s->port.rxBufferSize;
+        }
+        CLEAR_BIT(huart->Instance->CR1, (USART_CR1_PEIE));
+
+        /* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
+        CLEAR_BIT(huart->Instance->CR3, USART_CR3_EIE);
+
+        __HAL_UART_SEND_REQ(huart, UART_RXDATA_FLUSH_REQUEST);
+    }
+
+    /* UART parity error interrupt occurred -------------------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_PE) != RESET)) {
+        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_PEF);
+    }
+
+    /* UART frame error interrupt occurred --------------------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_FE) != RESET)) {
+        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_FEF);
+    }
+
+    /* UART noise error interrupt occurred --------------------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_NE) != RESET)) {
+        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_NEF);
+    }
+
+    /* UART Over-Run interrupt occurred -----------------------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_ORE) != RESET)) {
+        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_OREF);
+    }
+
+    /* UART in mode Transmitter ------------------------------------------------*/
+    if (
+#ifdef USE_DMA
+        !s->txDMAResource &&
+#endif
+        (__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET)) {
+        /* Check that a Tx process is ongoing */
+        if (huart->gState != HAL_UART_STATE_BUSY_TX) {
+            if (s->port.txBufferTail == s->port.txBufferHead) {
+                huart->TxXferCount = 0;
+                /* Disable the UART Transmit Data Register Empty Interrupt */
+                CLEAR_BIT(huart->Instance->CR1, USART_CR1_TXEIE);
+            } else {
+                if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE)) {
+                    huart->Instance->TDR = (((uint16_t) s->port.txBuffer[s->port.txBufferTail]) & (uint16_t) 0x01FFU);
+                } else {
+                    huart->Instance->TDR = (uint8_t)(s->port.txBuffer[s->port.txBufferTail]);
+                }
+                s->port.txBufferTail = (s->port.txBufferTail + 1) % s->port.txBufferSize;
+            }
+        }
+    }
+
+    /* UART in mode Transmitter (transmission end) -----------------------------*/
+    if ((__HAL_UART_GET_IT(huart, UART_IT_TC) != RESET)) {
+        HAL_UART_IRQHandler(huart);
+#ifdef USE_DMA
+        if (s->txDMAResource) {
+            handleUsartTxDma(s);
+        }
+#endif
+    }
+
+    if (__HAL_UART_GET_IT(huart, UART_IT_IDLE)) {
+        if (s->port.idleCallback) {
+            s->port.idleCallback();
+        }
+
+        __HAL_UART_CLEAR_IDLEFLAG(huart);
+    }
+
+}
 #endif // USE_UART

src/main/drivers/serial_uart_impl.h

@@ -137,13 +137,10 @@ typedef struct uartHardware_s {
 #ifdef USE_DMA
     dmaResource_t *txDMAResource;
     dmaResource_t *rxDMAResource;
-#if defined(STM32F4) || defined(STM32F7)
+    // For H7, {tx|rx}DMAChannel are DMAMUX input index for  peripherals (DMA_REQUEST_xxx); RM0433 Table 110.
-    uint32_t DMAChannel;
+    // For F4 and F7, these are 32-bit channel identifiers (DMA_CHANNEL_x).
-#elif defined(STM32H7)
+    uint32_t txDMAChannel;
-    // DMAMUX input from peripherals (DMA_REQUEST_xxx); RM0433 Table 110.
+    uint32_t rxDMAChannel;
-    uint8_t txDMARequest;
-    uint8_t rxDMARequest;
-#endif
 #endif // USE_DMA
 
     uartPinDef_t rxPins[UARTHARDWARE_MAX_PINS];
@@ -170,12 +167,10 @@ typedef struct uartHardware_s {
     uint8_t txPriority;
     uint8_t rxPriority;
 
-#if defined(STM32H7) || defined(STM32F4)
     volatile uint8_t *txBuffer;
     volatile uint8_t *rxBuffer;
     uint16_t txBufferSize;
     uint16_t rxBufferSize;
-#endif
 } uartHardware_t;
 
 extern const uartHardware_t uartHardware[];
@@ -188,15 +183,8 @@ typedef struct uartDevice_s {
     const uartHardware_t *hardware;
     uartPinDef_t rx;
     uartPinDef_t tx;
-#if defined(STM32H7) || defined(STM32F4)
-    // For H7, buffers with possible DMA access is placed in D2 SRAM.
-    // For F4, buffers should NOT be in CCM DATA RAM (uartDevice is).
     volatile uint8_t *rxBuffer;
     volatile uint8_t *txBuffer;
-#else
-    volatile uint8_t rxBuffer[UART_RX_BUFFER_SIZE];
-    volatile uint8_t txBuffer[UART_TX_BUFFER_SIZE];
-#endif
 } uartDevice_t;
 
 extern uartDevice_t *uartDevmap[];
@@ -210,3 +198,55 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 void uartIrqHandler(uartPort_t *s);
 
 void uartReconfigure(uartPort_t *uartPort);
+
+void uartConfigureDma(uartDevice_t *uartdev);
+
+void uartDmaIrqHandler(dmaChannelDescriptor_t* descriptor);
+
+#if defined(STM32F3) || defined(STM32F7) || defined(STM32H7)
+#define UART_REG_RXD(base) ((base)->RDR)
+#define UART_REG_TXD(base) ((base)->TDR)
+#elif defined(STM32F1) || defined(STM32F4)
+#define UART_REG_RXD(base) ((base)->DR)
+#define UART_REG_TXD(base) ((base)->DR)
+#endif
+
+#define UART_BUFFER(type, n, rxtx) type volatile uint8_t uart ## n ## rxtx ## xBuffer[UART_ ## rxtx ## X_BUFFER_SIZE]
+
+#define UART_BUFFERS_EXTERN(n) \
+    UART_BUFFER(extern, n, R); \
+    UART_BUFFER(extern, n, T); struct dummy_s
+
+#ifdef USE_UART1
+UART_BUFFERS_EXTERN(1);
+#endif
+
+#ifdef USE_UART2
+UART_BUFFERS_EXTERN(2);
+#endif
+
+#ifdef USE_UART3
+UART_BUFFERS_EXTERN(3);
+#endif
+
+#ifdef USE_UART4
+UART_BUFFERS_EXTERN(4);
+#endif
+
+#ifdef USE_UART5
+UART_BUFFERS_EXTERN(5);
+#endif
+
+#ifdef USE_UART6
+UART_BUFFERS_EXTERN(6);
+#endif
+
+#ifdef USE_UART7
+UART_BUFFERS_EXTERN(7);
+#endif
+
+#ifdef USE_UART8
+UART_BUFFERS_EXTERN(8);
+#endif
+
+#undef UART_BUFFERS_EXTERN

src/main/drivers/serial_uart_stm32f10x.c

@@ -73,7 +73,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc = RCC_APB2(USART1),
         .irqn = USART1_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART1_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART1
+        .rxPriority = NVIC_PRIO_SERIALUART1,
+        .txBuffer = uart1TxBuffer,
+        .rxBuffer = uart1RxBuffer,
+        .txBufferSize = sizeof(uart1TxBuffer),
+        .rxBufferSize = sizeof(uart1RxBuffer),
     },
 #endif
 #ifdef USE_UART2
@@ -88,7 +92,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc = RCC_APB1(USART2),
         .irqn = USART2_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART2,
-        .rxPriority = NVIC_PRIO_SERIALUART2
+        .rxPriority = NVIC_PRIO_SERIALUART2,
+        .txBuffer = uart2TxBuffer,
+        .rxBuffer = uart2RxBuffer,
+        .txBufferSize = sizeof(uart2TxBuffer),
+        .rxBufferSize = sizeof(uart2RxBuffer),
     },
 #endif
 #ifdef USE_UART3
@@ -103,12 +111,16 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc = RCC_APB1(USART3),
         .irqn = USART3_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART3,
-        .rxPriority = NVIC_PRIO_SERIALUART3
+        .rxPriority = NVIC_PRIO_SERIALUART3,
+        .txBuffer = uart3TxBuffer,
+        .rxBuffer = uart3RxBuffer,
+        .txBufferSize = sizeof(uart3TxBuffer),
+        .rxBufferSize = sizeof(uart3RxBuffer),
     },
 #endif
 };
 
-void uart_tx_dma_IRQHandler(dmaChannelDescriptor_t* descriptor)
+void uartDmaIrqHandler(dmaChannelDescriptor_t* descriptor)
 {
     uartPort_t *s = (uartPort_t*)(descriptor->userParam);
     DMA_CLEAR_FLAG(descriptor, DMA_IT_TCIF);
@@ -132,30 +144,18 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 
     s->port.baudRate = baudRate;
 
-    s->port.rxBuffer = uartdev->rxBuffer;
-    s->port.txBuffer = uartdev->txBuffer;
-    s->port.rxBufferSize = ARRAYLEN(uartdev->rxBuffer);
-    s->port.txBufferSize = ARRAYLEN(uartdev->txBuffer);
-
     const uartHardware_t *hardware = uartdev->hardware;
 
     s->USARTx = hardware->reg;
 
+    s->port.rxBuffer = hardware->rxBuffer;
+    s->port.txBuffer = hardware->txBuffer;
+    s->port.rxBufferSize = hardware->rxBufferSize;
+    s->port.txBufferSize = hardware->txBufferSize;
+
     RCC_ClockCmd(hardware->rcc, ENABLE);
 
-    if (hardware->rxDMAResource) {
+    uartConfigureDma(uartdev);
-        dmaInit(dmaGetIdentifier(hardware->rxDMAResource), OWNER_SERIAL_RX, RESOURCE_INDEX(device));
-        s->rxDMAResource = hardware->rxDMAResource;
-        s->rxDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->DR;
-    }
-
-    if (hardware->txDMAResource) {
-        const dmaIdentifier_e identifier = dmaGetIdentifier(hardware->txDMAResource);
-        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(device));
-        dmaSetHandler(identifier, uart_tx_dma_IRQHandler, hardware->txPriority, (uint32_t)s);
-        s->txDMAResource = hardware->txDMAResource;
-        s->txDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->DR;
-    }
 
     IO_t rxIO = IOGetByTag(uartdev->rx.pin);
     IO_t txIO = IOGetByTag(uartdev->tx.pin);

src/main/drivers/serial_uart_stm32f30x.c

@@ -83,6 +83,18 @@
 # define UART3_TX_DMA 0
 #endif
 
+#ifdef USE_UART4_RX_DMA
+# define UART4_RX_DMA DMA2_Channel3
+#else
+# define UART4_RX_DMA 0
+#endif
+
+#ifdef USE_UART4_TX_DMA
+# define UART4_TX_DMA DMA2_Channel5
+#else
+# define UART4_TX_DMA 0
+#endif
+
 const uartHardware_t uartHardware[UARTDEV_COUNT] = {
 #ifdef USE_UART1
     {
@@ -97,6 +109,10 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .irqn = USART1_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART1_TXDMA,
         .rxPriority = NVIC_PRIO_SERIALUART1_RXDMA,
+        .txBuffer = uart1TxBuffer,
+        .rxBuffer = uart1RxBuffer,
+        .txBufferSize = sizeof(uart1TxBuffer),
+        .rxBufferSize = sizeof(uart1RxBuffer),
     },
 #endif
 
@@ -113,6 +129,10 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .irqn = USART2_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART2_TXDMA,
         .rxPriority = NVIC_PRIO_SERIALUART2_RXDMA,
+        .txBuffer = uart2TxBuffer,
+        .rxBuffer = uart2RxBuffer,
+        .txBufferSize = sizeof(uart2TxBuffer),
+        .rxBufferSize = sizeof(uart2RxBuffer),
     },
 #endif
 
@@ -129,6 +149,10 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .irqn = USART3_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART3_TXDMA,
         .rxPriority = NVIC_PRIO_SERIALUART3_RXDMA,
+        .txBuffer = uart3TxBuffer,
+        .rxBuffer = uart3RxBuffer,
+        .txBufferSize = sizeof(uart3TxBuffer),
+        .rxBufferSize = sizeof(uart3RxBuffer),
     },
 #endif
 
@@ -146,6 +170,10 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .irqn = UART4_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART4_TXDMA,
         .rxPriority = NVIC_PRIO_SERIALUART4_RXDMA,
+        .txBuffer = uart4TxBuffer,
+        .rxBuffer = uart4RxBuffer,
+        .txBufferSize = sizeof(uart4TxBuffer),
+        .rxBufferSize = sizeof(uart4RxBuffer),
     },
 #endif
 
@@ -163,11 +191,15 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .irqn = UART5_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART5,
         .rxPriority = NVIC_PRIO_SERIALUART5,
+        .txBuffer = uart5TxBuffer,
+        .rxBuffer = uart5RxBuffer,
+        .txBufferSize = sizeof(uart5TxBuffer),
+        .rxBufferSize = sizeof(uart5RxBuffer),
     },
 #endif
 };
 
-static void handleUsartTxDma(dmaChannelDescriptor_t* descriptor)
+void uartDmaIrqHandler(dmaChannelDescriptor_t* descriptor)
 {
     uartPort_t *s = (uartPort_t*)(descriptor->userParam);
     DMA_CLEAR_FLAG(descriptor, DMA_IT_TCIF);
@@ -217,30 +249,19 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 
     s->port.baudRate = baudRate;
 
-    s->port.rxBuffer = uartDev->rxBuffer;
-    s->port.txBuffer = uartDev->txBuffer;
-    s->port.rxBufferSize = sizeof(uartDev->rxBuffer);
-    s->port.txBufferSize = sizeof(uartDev->txBuffer);
-
     const uartHardware_t *hardware = uartDev->hardware;
 
     s->USARTx = hardware->reg;
 
+
+    s->port.rxBuffer = hardware->rxBuffer;
+    s->port.txBuffer = hardware->txBuffer;
+    s->port.rxBufferSize = hardware->rxBufferSize;
+    s->port.txBufferSize = hardware->txBufferSize;
+
     RCC_ClockCmd(hardware->rcc, ENABLE);
 
-    if (hardware->rxDMAResource) {
+    uartConfigureDma(uartDev);
-        dmaInit(dmaGetIdentifier(hardware->rxDMAResource), OWNER_SERIAL_RX, RESOURCE_INDEX(device));
-        s->rxDMAResource = hardware->rxDMAResource;
-        s->rxDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->RDR;
-    }
-
-    if (hardware->txDMAResource) {
-        const dmaIdentifier_e identifier = dmaGetIdentifier(hardware->txDMAResource);
-        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(device));
-        dmaSetHandler(identifier, handleUsartTxDma, hardware->txPriority, (uint32_t)s);
-        s->txDMAResource = hardware->txDMAResource;
-        s->txDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->TDR;
-    }
 
     serialUARTInitIO(IOGetByTag(uartDev->tx.pin), IOGetByTag(uartDev->rx.pin), mode, options, hardware->af, device);
 

src/main/drivers/serial_uart_stm32f4xx.c

@@ -39,42 +39,13 @@
 #include "drivers/serial_uart.h"
 #include "drivers/serial_uart_impl.h"
 
-#define UART_BUFFERS(n) \
-  volatile uint8_t uart ## n ## RxBuffer[UART_RX_BUFFER_SIZE]; \
-  volatile uint8_t uart ## n ## TxBuffer[UART_TX_BUFFER_SIZE]; struct dummy_s
-
-#ifdef USE_UART1
-UART_BUFFERS(1);
-#endif
-
-#ifdef USE_UART2
-UART_BUFFERS(2);
-#endif
-
-#ifdef USE_UART3
-UART_BUFFERS(3);
-#endif
-
-#ifdef USE_UART4
-UART_BUFFERS(4);
-#endif
-
-#ifdef USE_UART5
-UART_BUFFERS(5);
-#endif
-
-#ifdef USE_UART6
-UART_BUFFERS(6);
-#endif
-
-#undef UART_BUFFERS
-
 const uartHardware_t uartHardware[UARTDEV_COUNT] = {
 #ifdef USE_UART1
     {
         .device = UARTDEV_1,
         .reg = USART1,
-        .DMAChannel = DMA_Channel_4,
+        .rxDMAChannel = DMA_Channel_4,
+        .txDMAChannel = DMA_Channel_4,
 #ifdef USE_UART1_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA2_Stream5,
 #endif
@@ -107,7 +78,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_2,
         .reg = USART2,
-        .DMAChannel = DMA_Channel_4,
+        .rxDMAChannel = DMA_Channel_4,
+        .txDMAChannel = DMA_Channel_4,
 #ifdef USE_UART2_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream5,
 #endif
@@ -132,7 +104,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_3,
         .reg = USART3,
-        .DMAChannel = DMA_Channel_4,
+        .rxDMAChannel = DMA_Channel_4,
+        .txDMAChannel = DMA_Channel_4,
 #ifdef USE_UART3_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream1,
 #endif
@@ -157,7 +130,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_4,
         .reg = UART4,
-        .DMAChannel = DMA_Channel_4,
+        .rxDMAChannel = DMA_Channel_4,
+        .txDMAChannel = DMA_Channel_4,
 #ifdef USE_UART4_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream2,
 #endif
@@ -182,7 +156,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_5,
         .reg = UART5,
-        .DMAChannel = DMA_Channel_4,
+        .rxDMAChannel = DMA_Channel_4,
+        .txDMAChannel = DMA_Channel_4,
 #ifdef USE_UART5_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream0,
 #endif
@@ -207,7 +182,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_6,
         .reg = USART6,
-        .DMAChannel = DMA_Channel_5,
+        .rxDMAChannel = DMA_Channel_5,
+        .txDMAChannel = DMA_Channel_5,
 #ifdef USE_UART6_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA2_Stream1,
 #endif
@@ -246,7 +222,7 @@ static void handleUsartTxDma(uartPort_t *s)
     uartTryStartTxDMA(s);
 }
 
-void dmaIRQHandler(dmaChannelDescriptor_t* descriptor)
+void uartDmaIrqHandler(dmaChannelDescriptor_t* descriptor)
 {
     uartPort_t *s = &(((uartDevice_t*)(descriptor->userParam))->port);
     if (DMA_GET_FLAG_STATUS(descriptor, DMA_IT_TCIF))
@@ -292,21 +268,9 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 
     s->USARTx = hardware->reg;
 
-    if (hardware->rxDMAResource) {
+#ifdef USE_DMA
-        dmaInit(dmaGetIdentifier(hardware->rxDMAResource), OWNER_SERIAL_RX, RESOURCE_INDEX(device));
+    uartConfigureDma(uart);
-        s->rxDMAChannel = hardware->DMAChannel;
+#endif
-        s->rxDMAResource = hardware->rxDMAResource;
-        s->rxDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->DR;
-    }
-
-    if (hardware->txDMAResource) {
-        const dmaIdentifier_e identifier = dmaGetIdentifier(hardware->txDMAResource);
-        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(device));
-        dmaSetHandler(identifier, dmaIRQHandler, hardware->txPriority, (uint32_t)uart);
-        s->txDMAChannel = hardware->DMAChannel;
-        s->txDMAResource = hardware->txDMAResource;
-        s->txDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->DR;
-    }
 
     IO_t txIO = IOGetByTag(uart->tx.pin);
     IO_t rxIO = IOGetByTag(uart->rx.pin);
@@ -330,7 +294,8 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
         }
     }
 
-    if (!(s->rxDMAChannel)) {
+#ifdef USE_DMA
+    if (!(s->rxDMAResource)) {
         NVIC_InitTypeDef NVIC_InitStructure;
 
         NVIC_InitStructure.NVIC_IRQChannel = hardware->irqn;
@@ -339,6 +304,7 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
         NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
         NVIC_Init(&NVIC_InitStructure);
     }
+#endif
 
     return s;
 }

src/main/drivers/serial_uart_stm32f7xx.c

@@ -41,14 +41,13 @@
 
 #include "stm32f7xx_ll_usart.h"
 
-static void handleUsartTxDma(uartPort_t *s);
-
 const uartHardware_t uartHardware[UARTDEV_COUNT] = {
 #ifdef USE_UART1
     {
         .device = UARTDEV_1,
         .reg = USART1,
-        .DMAChannel = DMA_CHANNEL_4,
+        .rxDMAChannel = DMA_CHANNEL_4,
+        .txDMAChannel = DMA_CHANNEL_4,
 #ifdef USE_UART1_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA2_Stream5,
 #endif
@@ -75,7 +74,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb2 = RCC_APB2(USART1),
         .rxIrq = USART1_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART1_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART1
+        .rxPriority = NVIC_PRIO_SERIALUART1,
+        .txBuffer = uart1TxBuffer,
+        .rxBuffer = uart1RxBuffer,
+        .txBufferSize = sizeof(uart1TxBuffer),
+        .rxBufferSize = sizeof(uart1RxBuffer),
     },
 #endif
 
@@ -83,7 +86,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_2,
         .reg = USART2,
-        .DMAChannel = DMA_CHANNEL_4,
+        .rxDMAChannel = DMA_CHANNEL_4,
+        .txDMAChannel = DMA_CHANNEL_4,
 #ifdef USE_UART2_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream5,
 #endif
@@ -104,7 +108,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(USART2),
         .rxIrq = USART2_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART2_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART2
+        .rxPriority = NVIC_PRIO_SERIALUART2,
+        .txBuffer = uart2TxBuffer,
+        .rxBuffer = uart2RxBuffer,
+        .txBufferSize = sizeof(uart2TxBuffer),
+        .rxBufferSize = sizeof(uart2RxBuffer),
     },
 #endif
 
@@ -112,7 +120,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_3,
         .reg = USART3,
-        .DMAChannel = DMA_CHANNEL_4,
+        .rxDMAChannel = DMA_CHANNEL_4,
+        .txDMAChannel = DMA_CHANNEL_4,
 #ifdef USE_UART3_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream1,
 #endif
@@ -135,7 +144,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(USART3),
         .rxIrq = USART3_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART3_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART3
+        .rxPriority = NVIC_PRIO_SERIALUART3,
+        .txBuffer = uart3TxBuffer,
+        .rxBuffer = uart3RxBuffer,
+        .txBufferSize = sizeof(uart3TxBuffer),
+        .rxBufferSize = sizeof(uart3RxBuffer),
     },
 #endif
 
@@ -143,7 +156,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_4,
         .reg = UART4,
-        .DMAChannel = DMA_CHANNEL_4,
+        .rxDMAChannel = DMA_CHANNEL_4,
+        .txDMAChannel = DMA_CHANNEL_4,
 #ifdef USE_UART4_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream2,
 #endif
@@ -172,7 +186,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(UART4),
         .rxIrq = UART4_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART4_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART4
+        .rxPriority = NVIC_PRIO_SERIALUART4,
+        .txBuffer = uart4TxBuffer,
+        .rxBuffer = uart4RxBuffer,
+        .txBufferSize = sizeof(uart4TxBuffer),
+        .rxBufferSize = sizeof(uart4RxBuffer),
     },
 #endif
 
@@ -180,7 +198,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_5,
         .reg = UART5,
-        .DMAChannel = DMA_CHANNEL_4,
+        .rxDMAChannel = DMA_CHANNEL_4,
+        .txDMAChannel = DMA_CHANNEL_4,
 #ifdef USE_UART5_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream0,
 #endif
@@ -209,7 +228,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(UART5),
         .rxIrq = UART5_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART5_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART5
+        .rxPriority = NVIC_PRIO_SERIALUART5,
+        .txBuffer = uart5TxBuffer,
+        .rxBuffer = uart5RxBuffer,
+        .txBufferSize = sizeof(uart5TxBuffer),
+        .rxBufferSize = sizeof(uart5RxBuffer),
     },
 #endif
 
@@ -217,7 +240,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_6,
         .reg = USART6,
-        .DMAChannel = DMA_CHANNEL_5,
+        .rxDMAChannel = DMA_CHANNEL_5,
+        .txDMAChannel = DMA_CHANNEL_5,
 #ifdef USE_UART6_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA2_Stream1,
 #endif
@@ -238,7 +262,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb2 = RCC_APB2(USART6),
         .rxIrq = USART6_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART6_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART6
+        .rxPriority = NVIC_PRIO_SERIALUART6,
+        .txBuffer = uart6TxBuffer,
+        .rxBuffer = uart6RxBuffer,
+        .txBufferSize = sizeof(uart6TxBuffer),
+        .rxBufferSize = sizeof(uart6RxBuffer),
     },
 #endif
 
@@ -246,7 +274,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_7,
         .reg = UART7,
-        .DMAChannel = DMA_CHANNEL_5,
+        .rxDMAChannel = DMA_CHANNEL_5,
+        .txDMAChannel = DMA_CHANNEL_5,
 #ifdef USE_UART7_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream3,
 #endif
@@ -275,7 +304,11 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(UART7),
         .rxIrq = UART7_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART7_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART7
+        .rxPriority = NVIC_PRIO_SERIALUART7,
+        .txBuffer = uart7TxBuffer,
+        .rxBuffer = uart7RxBuffer,
+        .txBufferSize = sizeof(uart7TxBuffer),
+        .rxBufferSize = sizeof(uart7RxBuffer),
     },
 #endif
 
@@ -283,7 +316,8 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
     {
         .device = UARTDEV_8,
         .reg = UART8,
-        .DMAChannel = DMA_CHANNEL_5,
+        .rxDMAChannel = DMA_CHANNEL_5,
+        .txDMAChannel = DMA_CHANNEL_5,
 #ifdef USE_UART8_RX_DMA
         .rxDMAResource = (dmaResource_t *)DMA1_Stream6,
 #endif
@@ -302,99 +336,15 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .rcc_apb1 = RCC_APB1(UART8),
         .rxIrq = UART8_IRQn,
         .txPriority = NVIC_PRIO_SERIALUART8_TXDMA,
-        .rxPriority = NVIC_PRIO_SERIALUART8
+        .rxPriority = NVIC_PRIO_SERIALUART8,
+        .txBuffer = uart8TxBuffer,
+        .rxBuffer = uart8RxBuffer,
+        .txBufferSize = sizeof(uart8TxBuffer),
+        .rxBufferSize = sizeof(uart8RxBuffer),
     },
 #endif
 };
 
-void uartIrqHandler(uartPort_t *s)
-{
-    UART_HandleTypeDef *huart = &s->Handle;
-    /* UART in mode Receiver ---------------------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_RXNE) != RESET)) {
-        uint8_t rbyte = (uint8_t)(huart->Instance->RDR & (uint8_t) 0xff);
-
-        if (s->port.rxCallback) {
-            s->port.rxCallback(rbyte, s->port.rxCallbackData);
-        } else {
-            s->port.rxBuffer[s->port.rxBufferHead] = rbyte;
-            s->port.rxBufferHead = (s->port.rxBufferHead + 1) % s->port.rxBufferSize;
-        }
-        CLEAR_BIT(huart->Instance->CR1, (USART_CR1_PEIE));
-
-        /* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
-        CLEAR_BIT(huart->Instance->CR3, USART_CR3_EIE);
-
-        __HAL_UART_SEND_REQ(huart, UART_RXDATA_FLUSH_REQUEST);
-    }
-
-    /* UART parity error interrupt occurred -------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_PE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_PEF);
-    }
-
-    /* UART frame error interrupt occurred --------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_FE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_FEF);
-    }
-
-    /* UART noise error interrupt occurred --------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_NE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_NEF);
-    }
-
-    /* UART Over-Run interrupt occurred -----------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_ORE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_OREF);
-    }
-
-    /* UART in mode Transmitter ------------------------------------------------*/
-    if (!s->txDMAResource && (__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET)) {
-        /* Check that a Tx process is ongoing */
-        if (huart->gState != HAL_UART_STATE_BUSY_TX) {
-            if (s->port.txBufferTail == s->port.txBufferHead) {
-                huart->TxXferCount = 0;
-                /* Disable the UART Transmit Data Register Empty Interrupt */
-                CLEAR_BIT(huart->Instance->CR1, USART_CR1_TXEIE);
-            } else {
-                if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE)) {
-                    huart->Instance->TDR = (((uint16_t) s->port.txBuffer[s->port.txBufferTail]) & (uint16_t) 0x01FFU);
-                } else {
-                    huart->Instance->TDR = (uint8_t)(s->port.txBuffer[s->port.txBufferTail]);
-                }
-                s->port.txBufferTail = (s->port.txBufferTail + 1) % s->port.txBufferSize;
-            }
-        }
-    }
-
-    /* UART in mode Transmitter (transmission end) -----------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_TC) != RESET)) {
-        HAL_UART_IRQHandler(huart);
-        if (s->txDMAResource) {
-            handleUsartTxDma(s);
-        }
-    }
-
-    if (__HAL_UART_GET_IT(huart, UART_IT_IDLE)) {
-        if (s->port.idleCallback) {
-            s->port.idleCallback();
-        }
-
-        __HAL_UART_CLEAR_IDLEFLAG(huart);
-    }
-}
-
-static void handleUsartTxDma(uartPort_t *s)
-{
-    uartTryStartTxDMA(s);
-}
-
-void dmaIRQHandler(dmaChannelDescriptor_t* descriptor)
-{
-    uartPort_t *s = &(((uartDevice_t*)(descriptor->userParam))->port);
-    HAL_DMA_IRQHandler(&s->txDMAHandle);
-}
-
 // XXX Should serialUART be consolidated?
 
 uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode, portOptions_e options)
@@ -410,32 +360,18 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 
     s->port.baudRate = baudRate;
 
-    s->port.rxBuffer = uartdev->rxBuffer;
-    s->port.txBuffer = uartdev->txBuffer;
-    s->port.rxBufferSize = ARRAYLEN(uartdev->rxBuffer);
-    s->port.txBufferSize = ARRAYLEN(uartdev->txBuffer);
-
     const uartHardware_t *hardware = uartdev->hardware;
 
     s->USARTx = hardware->reg;
 
-    if (hardware->rxDMAResource) {
+    s->port.rxBuffer = hardware->rxBuffer;
-        s->rxDMAChannel = hardware->DMAChannel;
+    s->port.txBuffer = hardware->txBuffer;
-        s->rxDMAResource = hardware->rxDMAResource;
+    s->port.rxBufferSize = hardware->rxBufferSize;
-    }
+    s->port.txBufferSize = hardware->txBufferSize;
 
-    if (hardware->txDMAResource) {
+#ifdef USE_DMA
-        s->txDMAChannel = hardware->DMAChannel;
+    uartConfigureDma(uartdev);
-        s->txDMAResource = hardware->txDMAResource;
+#endif
-
-        // DMA TX Interrupt
-        dmaIdentifier_e identifier = dmaGetIdentifier(hardware->txDMAResource);
-        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(device));
-        dmaSetHandler(identifier, dmaIRQHandler, hardware->txPriority, (uint32_t)uartdev);
-    }
-
-    s->txDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->TDR;
-    s->rxDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->RDR;
 
     s->Handle.Instance = hardware->reg;
 
@@ -464,10 +400,12 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
         }
     }
 
-    if (!s->rxDMAChannel) {
+#ifdef USE_DMA
+    if (!s->rxDMAResource) {
         HAL_NVIC_SetPriority(hardware->rxIrq, NVIC_PRIORITY_BASE(hardware->rxPriority), NVIC_PRIORITY_SUB(hardware->rxPriority));
         HAL_NVIC_EnableIRQ(hardware->rxIrq);
     }
+#endif
 
     return s;
 }

src/main/drivers/serial_uart_stm32h7xx.c

@@ -88,53 +88,15 @@
 #define UART8_RX_DMA_STREAM NULL
 #endif
 
-#define UART_BUFFERS(n) \
-  DMA_RAM volatile uint8_t uart ## n ## RxBuffer[UART_RX_BUFFER_SIZE]; \
-  DMA_RAM volatile uint8_t uart ## n ## TxBuffer[UART_TX_BUFFER_SIZE]; struct dummy_s
-
-#ifdef USE_UART1
-UART_BUFFERS(1);
-#endif
-
-#ifdef USE_UART2
-UART_BUFFERS(2);
-#endif
-
-#ifdef USE_UART3
-UART_BUFFERS(3);
-#endif
-
-#ifdef USE_UART4
-UART_BUFFERS(4);
-#endif
-
-#ifdef USE_UART5
-UART_BUFFERS(5);
-#endif
-
-#ifdef USE_UART6
-UART_BUFFERS(6);
-#endif
-
-#ifdef USE_UART7
-UART_BUFFERS(7);
-#endif
-
-#ifdef USE_UART8
-UART_BUFFERS(8);
-#endif
-
-#undef UART_BUFFERS
-
 const uartHardware_t uartHardware[UARTDEV_COUNT] = {
 #ifdef USE_UART1
     {
         .device = UARTDEV_1,
         .reg = USART1,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_USART1_RX,
+        .rxDMAChannel = DMA_REQUEST_USART1_RX,
         .rxDMAResource = (dmaResource_t *)UART1_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_USART1_TX,
+        .txDMAChannel = DMA_REQUEST_USART1_TX,
         .txDMAResource = (dmaResource_t *)UART1_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -163,9 +125,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_2,
         .reg = USART2,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_USART2_RX,
+        .rxDMAChannel = DMA_REQUEST_USART2_RX,
         .rxDMAResource = (dmaResource_t *)UART2_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_USART2_TX,
+        .txDMAChannel = DMA_REQUEST_USART2_TX,
         .txDMAResource = (dmaResource_t *)UART2_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -192,9 +154,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_3,
         .reg = USART3,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_USART3_RX,
+        .rxDMAChannel = DMA_REQUEST_USART3_RX,
         .rxDMAResource = (dmaResource_t *)UART3_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_USART3_TX,
+        .txDMAChannel = DMA_REQUEST_USART3_TX,
         .txDMAResource = (dmaResource_t *)UART3_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -223,9 +185,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_4,
         .reg = UART4,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_UART4_RX,
+        .rxDMAChannel = DMA_REQUEST_UART4_RX,
         .rxDMAResource = (dmaResource_t *)UART4_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_UART4_TX,
+        .txDMAChannel = DMA_REQUEST_UART4_TX,
         .txDMAResource = (dmaResource_t *)UART4_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -258,9 +220,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_5,
         .reg = UART5,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_UART5_RX,
+        .rxDMAChannel = DMA_REQUEST_UART5_RX,
         .rxDMAResource = (dmaResource_t *)UART5_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_UART5_TX,
+        .txDMAChannel = DMA_REQUEST_UART5_TX,
         .txDMAResource = (dmaResource_t *)UART5_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -289,9 +251,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_6,
         .reg = USART6,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_USART6_RX,
+        .rxDMAChannel = DMA_REQUEST_USART6_RX,
         .rxDMAResource = (dmaResource_t *)UART6_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_USART6_TX,
+        .txDMAChannel = DMA_REQUEST_USART6_TX,
         .txDMAResource = (dmaResource_t *)UART6_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -318,9 +280,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_7,
         .reg = UART7,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_UART7_RX,
+        .rxDMAChannel = DMA_REQUEST_UART7_RX,
         .rxDMAResource = (dmaResource_t *)UART7_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_UART7_TX,
+        .txDMAChannel = DMA_REQUEST_UART7_TX,
         .txDMAResource = (dmaResource_t *)UART7_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -351,9 +313,9 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
         .device = UARTDEV_8,
         .reg = UART8,
 #ifdef USE_DMA
-        .rxDMARequest = DMA_REQUEST_UART8_RX,
+        .rxDMAChannel = DMA_REQUEST_UART8_RX,
         .rxDMAResource = (dmaResource_t *)UART8_RX_DMA_STREAM,
-        .txDMARequest = DMA_REQUEST_UART8_TX,
+        .txDMAChannel = DMA_REQUEST_UART8_TX,
         .txDMAResource = (dmaResource_t *)UART8_TX_DMA_STREAM,
 #endif
         .rxPins = {
@@ -374,107 +336,6 @@ const uartHardware_t uartHardware[UARTDEV_COUNT] = {
 #endif
 };
 
-#ifdef USE_DMA
-static void handleUsartTxDma(uartPort_t *s);
-#endif
-
-void uartIrqHandler(uartPort_t *s)
-{
-    UART_HandleTypeDef *huart = &s->Handle;
-    /* UART in mode Receiver ---------------------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_RXNE) != RESET)) {
-        uint8_t rbyte = (uint8_t)(huart->Instance->RDR & (uint8_t) 0xff);
-
-        if (s->port.rxCallback) {
-            s->port.rxCallback(rbyte, s->port.rxCallbackData);
-        } else {
-            s->port.rxBuffer[s->port.rxBufferHead] = rbyte;
-            s->port.rxBufferHead = (s->port.rxBufferHead + 1) % s->port.rxBufferSize;
-        }
-        CLEAR_BIT(huart->Instance->CR1, (USART_CR1_PEIE));
-
-        /* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
-        CLEAR_BIT(huart->Instance->CR3, USART_CR3_EIE);
-
-        __HAL_UART_SEND_REQ(huart, UART_RXDATA_FLUSH_REQUEST);
-    }
-
-    /* UART parity error interrupt occurred -------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_PE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_PEF);
-    }
-
-    /* UART frame error interrupt occurred --------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_FE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_FEF);
-    }
-
-    /* UART noise error interrupt occurred --------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_NE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_NEF);
-    }
-
-    /* UART Over-Run interrupt occurred -----------------------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_ORE) != RESET)) {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_OREF);
-    }
-
-    /* UART in mode Transmitter ------------------------------------------------*/
-    if (
-#ifdef USE_DMA
-        !s->txDMAResource &&
-#endif
-        (__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET)) {
-        /* Check that a Tx process is ongoing */
-        if (huart->gState != HAL_UART_STATE_BUSY_TX) {
-            if (s->port.txBufferTail == s->port.txBufferHead) {
-                huart->TxXferCount = 0;
-                /* Disable the UART Transmit Data Register Empty Interrupt */
-                CLEAR_BIT(huart->Instance->CR1, USART_CR1_TXEIE);
-            } else {
-                if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE)) {
-                    huart->Instance->TDR = (((uint16_t) s->port.txBuffer[s->port.txBufferTail]) & (uint16_t) 0x01FFU);
-                } else {
-                    huart->Instance->TDR = (uint8_t)(s->port.txBuffer[s->port.txBufferTail]);
-                }
-                s->port.txBufferTail = (s->port.txBufferTail + 1) % s->port.txBufferSize;
-            }
-        }
-    }
-
-    /* UART in mode Transmitter (transmission end) -----------------------------*/
-    if ((__HAL_UART_GET_IT(huart, UART_IT_TC) != RESET)) {
-        HAL_UART_IRQHandler(huart);
-#ifdef USE_DMA
-        if (s->txDMAResource) {
-            handleUsartTxDma(s);
-        }
-#endif
-    }
-
-    if (__HAL_UART_GET_IT(huart, UART_IT_IDLE)) {
-        if (s->port.idleCallback) {
-            s->port.idleCallback();
-        }
-
-        __HAL_UART_CLEAR_IDLEFLAG(huart);
-    }
-
-}
-
-#ifdef USE_DMA
-static void handleUsartTxDma(uartPort_t *s)
-{
-    uartTryStartTxDMA(s);
-}
-
-static void dmaIRQHandler(dmaChannelDescriptor_t* descriptor)
-{
-    uartPort_t *s = &(((uartDevice_t*)(descriptor->userParam))->port);
-    HAL_DMA_IRQHandler(&s->txDMAHandle);
-}
-#endif
-
 // XXX Should serialUART be consolidated?
 
 uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode, portOptions_e options)
@@ -494,39 +355,13 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
 
     s->USARTx = hardware->reg;
 
-#ifdef STM32H7
     s->port.rxBuffer = hardware->rxBuffer;
     s->port.txBuffer = hardware->txBuffer;
     s->port.rxBufferSize = hardware->rxBufferSize;
     s->port.txBufferSize = hardware->txBufferSize;
-#endif
 
 #ifdef USE_DMA
-    if (hardware->rxDMAResource) {
+    uartConfigureDma(uartdev);
-        s->rxDMAResource = hardware->rxDMAResource;
-#if defined(STM32H7)
-        s->rxDMARequest = hardware->rxDMARequest;
-#else // F4 & F7
-        s->rxDMAChannel = hardware->DMAChannel;
-#endif
-    }
-
-    if (hardware->txDMAResource) {
-        s->txDMAResource = hardware->txDMAResource;
-#if defined(STM32H7)
-        s->txDMARequest = hardware->txDMARequest;
-#else // F4 & F7
-        s->txDMAChannel = hardware->DMAChannel;
-#endif
-
-        // DMA TX Interrupt
-        dmaIdentifier_e identifier = dmaGetIdentifier(hardware->txDMAResource);
-        dmaInit(identifier, OWNER_SERIAL_TX, RESOURCE_INDEX(device));
-        dmaSetHandler(identifier, dmaIRQHandler, hardware->txPriority, (uint32_t)uartdev);
-    }
-
-    s->txDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->TDR;
-    s->rxDMAPeripheralBaseAddr = (uint32_t)&s->USARTx->RDR;
 #endif
 
     s->Handle.Instance = hardware->reg;
@@ -556,11 +391,7 @@ uartPort_t *serialUART(UARTDevice_e device, uint32_t baudRate, portMode_e mode,
     }
 
 #ifdef USE_DMA
-#if defined(STM32H7)
     if (!s->rxDMAResource)
-#else
-    if (!s->rxDMAChannel)
-#endif
 #endif
     {
         HAL_NVIC_SetPriority(hardware->rxIrq, NVIC_PRIORITY_BASE(hardware->rxPriority), NVIC_PRIORITY_SUB(hardware->rxPriority));