From 061a1d4844a0eeffca59ae09b2799cc8ff24e05b Mon Sep 17 00:00:00 2001 From: gdisirio Date: Wed, 14 Sep 2011 18:35:47 +0000 Subject: git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@3317 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/hal/platforms/STM32/uart_lld.c | 557 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 557 insertions(+) create mode 100644 os/hal/platforms/STM32/uart_lld.c (limited to 'os/hal/platforms/STM32/uart_lld.c') diff --git a/os/hal/platforms/STM32/uart_lld.c b/os/hal/platforms/STM32/uart_lld.c new file mode 100644 index 000000000..a9303744d --- /dev/null +++ b/os/hal/platforms/STM32/uart_lld.c @@ -0,0 +1,557 @@ +/* + ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, + 2011 Giovanni Di Sirio. + + This file is part of ChibiOS/RT. + + ChibiOS/RT is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + ChibiOS/RT is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +/** + * @file STM32/uart_lld.c + * @brief STM32 low level UART driver code. + * + * @addtogroup UART + * @{ + */ + +#include "ch.h" +#include "hal.h" + +#if HAL_USE_UART || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +/** @brief USART1 UART driver identifier.*/ +#if STM32_UART_USE_USART1 || defined(__DOXYGEN__) +UARTDriver UARTD1; +#endif + +/** @brief USART2 UART driver identifier.*/ +#if STM32_UART_USE_USART2 || defined(__DOXYGEN__) +UARTDriver UARTD2; +#endif + +/** @brief USART3 UART driver identifier.*/ +#if STM32_UART_USE_USART3 || defined(__DOXYGEN__) +UARTDriver UARTD3; +#endif + +/*===========================================================================*/ +/* Driver local variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +/** + * @brief Status bits translation. + * + * @param[in] sr USART SR register value + * + * @return The error flags. + */ +static uartflags_t translate_errors(uint16_t sr) { + uartflags_t sts = 0; + + if (sr & USART_SR_ORE) + sts |= UART_OVERRUN_ERROR; + if (sr & USART_SR_PE) + sts |= UART_PARITY_ERROR; + if (sr & USART_SR_FE) + sts |= UART_FRAMING_ERROR; + if (sr & USART_SR_NE) + sts |= UART_NOISE_ERROR; + if (sr & USART_SR_LBD) + sts |= UART_BREAK_DETECTED; + return sts; +} + +/** + * @brief Puts the receiver in the UART_RX_IDLE state. + * + * @param[in] uartp pointer to the @p UARTDriver object + */ +static void set_rx_idle_loop(UARTDriver *uartp) { + uint32_t mode; + + /* RX DMA channel preparation, if the char callback is defined then the + TCIE interrupt is enabled too.*/ + if (uartp->config->rxchar_cb == NULL) + mode = STM32_DMA_CR_DIR_P2M | STM32_DMA_CR_CIRC | STM32_DMA_CR_TEIE; + else + mode = STM32_DMA_CR_DIR_P2M | STM32_DMA_CR_CIRC | STM32_DMA_CR_TEIE | + STM32_DMA_CR_TCIE; + dmaStreamSetMemory0(uartp->dmarx, &uartp->rxbuf); + dmaStreamSetTransactionSize(uartp->dmarx, 1); + dmaStreamSetMode(uartp->dmarx, uartp->dmamode | mode); + dmaStreamEnable(uartp->dmarx); +} + +/** + * @brief USART de-initialization. + * @details This function must be invoked with interrupts disabled. + * + * @param[in] uartp pointer to the @p UARTDriver object + */ +static void usart_stop(UARTDriver *uartp) { + + /* Stops RX and TX DMA channels.*/ + dmaStreamDisable(uartp->dmarx); + dmaStreamClearInterrupt(uartp->dmarx); + dmaStreamDisable(uartp->dmatx); + dmaStreamClearInterrupt(uartp->dmatx); + + /* Stops USART operations.*/ + uartp->usart->CR1 = 0; + uartp->usart->CR2 = 0; + uartp->usart->CR3 = 0; +} + +/** + * @brief USART initialization. + * @details This function must be invoked with interrupts disabled. + * + * @param[in] uartp pointer to the @p UARTDriver object + */ +static void usart_start(UARTDriver *uartp) { + uint16_t cr1; + USART_TypeDef *u = uartp->usart; + + /* Defensive programming, starting from a clean state.*/ + usart_stop(uartp); + + /* Baud rate setting.*/ + if (uartp->usart == USART1) + u->BRR = STM32_PCLK2 / uartp->config->speed; + else + u->BRR = STM32_PCLK1 / uartp->config->speed; + + /* Resetting eventual pending status flags.*/ + (void)u->SR; /* SR reset step 1.*/ + (void)u->DR; /* SR reset step 2.*/ + u->SR = 0; + + /* Note that some bits are enforced because required for correct driver + operations.*/ + if (uartp->config->txend2_cb == NULL) + cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE; + else + cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE | + USART_CR1_TCIE; + u->CR1 = uartp->config->cr1 | cr1; + u->CR2 = uartp->config->cr2 | USART_CR2_LBDIE; + u->CR3 = uartp->config->cr3 | USART_CR3_DMAT | USART_CR3_DMAR | + USART_CR3_EIE; + + /* Starting the receiver idle loop.*/ + set_rx_idle_loop(uartp); +} + +/** + * @brief RX DMA common service routine. + * + * @param[in] uartp pointer to the @p UARTDriver object + * @param[in] flags pre-shifted content of the ISR register + */ +static void uart_lld_serve_rx_end_irq(UARTDriver *uartp, uint32_t flags) { + + /* DMA errors handling.*/ +#if defined(STM32_UART_DMA_ERROR_HOOK) + if ((flags & STM32_DMA_ISR_TEIF) != 0) { + STM32_UART_DMA_ERROR_HOOK(uartp); + } +#else + (void)flags; +#endif + + if (uartp->rxstate == UART_RX_IDLE) { + /* Receiver in idle state, a callback is generated, if enabled, for each + received character and then the driver stays in the same state.*/ + if (uartp->config->rxchar_cb != NULL) + uartp->config->rxchar_cb(uartp, uartp->rxbuf); + } + else { + /* Receiver in active state, a callback is generated, if enabled, after + a completed transfer.*/ + dmaStreamDisable(uartp->dmarx); + uartp->rxstate = UART_RX_COMPLETE; + if (uartp->config->rxend_cb != NULL) + uartp->config->rxend_cb(uartp); + /* If the callback didn't explicitly change state then the receiver + automatically returns to the idle state.*/ + if (uartp->rxstate == UART_RX_COMPLETE) { + uartp->rxstate = UART_RX_IDLE; + set_rx_idle_loop(uartp); + } + } +} + +/** + * @brief TX DMA common service routine. + * + * @param[in] uartp pointer to the @p UARTDriver object + * @param[in] flags pre-shifted content of the ISR register + */ +static void uart_lld_serve_tx_end_irq(UARTDriver *uartp, uint32_t flags) { + + /* DMA errors handling.*/ +#if defined(STM32_UART_DMA_ERROR_HOOK) + if ((flags & STM32_DMA_ISR_TEIF) != 0) { + STM32_UART_DMA_ERROR_HOOK(uartp); + } +#else + (void)flags; +#endif + + dmaStreamDisable(uartp->dmatx); + /* A callback is generated, if enabled, after a completed transfer.*/ + uartp->txstate = UART_TX_COMPLETE; + if (uartp->config->txend1_cb != NULL) + uartp->config->txend1_cb(uartp); + /* If the callback didn't explicitly change state then the transmitter + automatically returns to the idle state.*/ + if (uartp->txstate == UART_TX_COMPLETE) + uartp->txstate = UART_TX_IDLE; +} + +/** + * @brief USART common service routine. + * + * @param[in] uartp pointer to the @p UARTDriver object + */ +static void serve_usart_irq(UARTDriver *uartp) { + uint16_t sr; + USART_TypeDef *u = uartp->usart; + + sr = u->SR; /* SR reset step 1.*/ + (void)u->DR; /* SR reset step 2.*/ + if (sr & (USART_SR_LBD | USART_SR_ORE | USART_SR_NE | + USART_SR_FE | USART_SR_PE)) { + u->SR = ~USART_SR_LBD; + if (uartp->config->rxerr_cb != NULL) + uartp->config->rxerr_cb(uartp, translate_errors(sr)); + } + if (sr & USART_SR_TC) { + u->SR = ~USART_SR_TC; + /* End of transmission, a callback is generated.*/ + if (uartp->config->txend2_cb != NULL) + uartp->config->txend2_cb(uartp); + } +} + +/*===========================================================================*/ +/* Driver interrupt handlers. */ +/*===========================================================================*/ + +#if STM32_UART_USE_USART1 || defined(__DOXYGEN__) +/** + * @brief USART1 IRQ handler. + * + * @isr + */ +CH_IRQ_HANDLER(USART1_IRQHandler) { + + CH_IRQ_PROLOGUE(); + + serve_usart_irq(&UARTD1); + + CH_IRQ_EPILOGUE(); +} +#endif /* STM32_UART_USE_USART1 */ + +#if STM32_UART_USE_USART2 || defined(__DOXYGEN__) +/** + * @brief USART2 IRQ handler. + * + * @isr + */ +CH_IRQ_HANDLER(USART2_IRQHandler) { + + CH_IRQ_PROLOGUE(); + + serve_usart_irq(&UARTD2); + + CH_IRQ_EPILOGUE(); +} +#endif /* STM32_UART_USE_USART2 */ + +#if STM32_UART_USE_USART3 || defined(__DOXYGEN__) +/** + * @brief USART3 IRQ handler. + * + * @isr + */ +CH_IRQ_HANDLER(USART3_IRQHandler) { + + CH_IRQ_PROLOGUE(); + + serve_usart_irq(&UARTD3); + + CH_IRQ_EPILOGUE(); +} +#endif /* STM32_UART_USE_USART3 */ + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief Low level UART driver initialization. + * + * @notapi + */ +void uart_lld_init(void) { + +#if STM32_UART_USE_USART1 + uartObjectInit(&UARTD1); + UARTD1.usart = USART1; + UARTD1.dmarx = STM32_DMA1_STREAM5; + UARTD1.dmatx = STM32_DMA1_STREAM4; +#endif + +#if STM32_UART_USE_USART2 + uartObjectInit(&UARTD2); + UARTD2.usart = USART2; + UARTD2.dmarx = STM32_DMA1_STREAM6; + UARTD2.dmatx = STM32_DMA1_STREAM7; +#endif + +#if STM32_UART_USE_USART3 + uartObjectInit(&UARTD3); + UARTD3.usart = USART3; + UARTD3.dmarx = STM32_DMA1_STREAM3; + UARTD3.dmatx = STM32_DMA1_STREAM2; +#endif +} + +/** + * @brief Configures and activates the UART peripheral. + * + * @param[in] uartp pointer to the @p UARTDriver object + * + * @notapi + */ +void uart_lld_start(UARTDriver *uartp) { + + if (uartp->state == UART_STOP) { +#if STM32_UART_USE_USART1 + if (&UARTD1 == uartp) { + bool_t b; + b = dmaStreamAllocate(STM32_DMA1_STREAM4, + STM32_UART_USART1_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_tx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #1", "stream already allocated"); + b = dmaStreamAllocate(STM32_DMA1_STREAM5, + STM32_UART_USART1_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_rx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #2", "stream already allocated"); + RCC->APB2ENR |= RCC_APB2ENR_USART1EN; + NVICEnableVector(USART1_IRQn, + CORTEX_PRIORITY_MASK(STM32_UART_USART1_IRQ_PRIORITY)); + } +#endif + +#if STM32_UART_USE_USART2 + if (&UARTD2 == uartp) { + bool_t b; + b = dmaStreamAllocate(STM32_DMA1_STREAM6, + STM32_UART_USART2_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_rx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #3", "stream already allocated"); + b = dmaStreamAllocate(STM32_DMA1_STREAM7, + STM32_UART_USART2_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_tx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #4", "stream already allocated"); + RCC->APB1ENR |= RCC_APB1ENR_USART2EN; + NVICEnableVector(USART2_IRQn, + CORTEX_PRIORITY_MASK(STM32_UART_USART2_IRQ_PRIORITY)); + } +#endif + +#if STM32_UART_USE_USART3 + if (&UARTD3 == uartp) { + bool_t b; + b = dmaStreamAllocate(STM32_DMA1_STREAM2, + STM32_UART_USART3_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_tx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #5", "stream already allocated"); + b = dmaStreamAllocate(STM32_DMA1_STREAM3, + STM32_UART_USART3_IRQ_PRIORITY, + (stm32_dmaisr_t)uart_lld_serve_rx_end_irq, + (void *)uartp); + chDbgAssert(!b, "uart_lld_start(), #6", "stream already allocated"); + RCC->APB1ENR |= RCC_APB1ENR_USART3EN; + NVICEnableVector(USART3_IRQn, + CORTEX_PRIORITY_MASK(STM32_UART_USART3_IRQ_PRIORITY)); + } +#endif + + /* Static DMA setup, the transfer size depends on the USART settings, + it is 16 bits if M=1 and PCE=0 else it is 8 bits.*/ + uartp->dmamode = STM32_DMA_CR_PL(STM32_UART_USART1_DMA_PRIORITY); + if ((uartp->config->cr1 & (USART_CR1_M | USART_CR1_PCE)) == USART_CR1_M) + uartp->dmamode |= STM32_DMA_CR_PSIZE_HWORD | STM32_DMA_CR_MSIZE_HWORD; + dmaStreamSetPeripheral(uartp->dmarx, &uartp->usart->DR); + dmaStreamSetPeripheral(uartp->dmatx, &uartp->usart->DR); + uartp->rxbuf = 0; + } + + uartp->rxstate = UART_RX_IDLE; + uartp->txstate = UART_TX_IDLE; + usart_start(uartp); +} + +/** + * @brief Deactivates the UART peripheral. + * + * @param[in] uartp pointer to the @p UARTDriver object + * + * @notapi + */ +void uart_lld_stop(UARTDriver *uartp) { + + if (uartp->state == UART_READY) { + usart_stop(uartp); + +#if STM32_UART_USE_USART1 + if (&UARTD1 == uartp) { + dmaStreamRelease(STM32_DMA1_STREAM4); + dmaStreamRelease(STM32_DMA1_STREAM5); + NVICDisableVector(USART1_IRQn); + RCC->APB2ENR &= ~RCC_APB2ENR_USART1EN; + return; + } +#endif + +#if STM32_UART_USE_USART2 + if (&UARTD2 == uartp) { + dmaStreamRelease(STM32_DMA1_STREAM6); + dmaStreamRelease(STM32_DMA1_STREAM7); + NVICDisableVector(USART2_IRQn); + RCC->APB1ENR &= ~RCC_APB1ENR_USART2EN; + return; + } +#endif + +#if STM32_UART_USE_USART3 + if (&UARTD3 == uartp) { + dmaStreamRelease(STM32_DMA1_STREAM2); + dmaStreamRelease(STM32_DMA1_STREAM3); + NVICDisableVector(USART3_IRQn); + RCC->APB1ENR &= ~RCC_APB1ENR_USART3EN; + return; + } +#endif + } +} + +/** + * @brief Starts a transmission on the UART peripheral. + * @note The buffers are organized as uint8_t arrays for data sizes below + * or equal to 8 bits else it is organized as uint16_t arrays. + * + * @param[in] uartp pointer to the @p UARTDriver object + * @param[in] n number of data frames to send + * @param[in] txbuf the pointer to the transmit buffer + * + * @notapi + */ +void uart_lld_start_send(UARTDriver *uartp, size_t n, const void *txbuf) { + + /* TX DMA channel preparation and start.*/ + dmaStreamSetMemory0(uartp->dmatx, txbuf); + dmaStreamSetTransactionSize(uartp->dmatx, n); + dmaStreamSetMode(uartp->dmatx, uartp->dmamode | STM32_DMA_CR_DIR_M2P | + STM32_DMA_CR_MINC | STM32_DMA_CR_TEIE | + STM32_DMA_CR_TCIE); + dmaStreamEnable(uartp->dmatx); +} + +/** + * @brief Stops any ongoing transmission. + * @note Stopping a transmission also suppresses the transmission callbacks. + * + * @param[in] uartp pointer to the @p UARTDriver object + * + * @return The number of data frames not transmitted by the + * stopped transmit operation. + * + * @notapi + */ +size_t uart_lld_stop_send(UARTDriver *uartp) { + + dmaStreamDisable(uartp->dmatx); + dmaStreamClearInterrupt(uartp->dmatx); + return dmaStreamGetTransactionSize(uartp->dmatx); +} + +/** + * @brief Starts a receive operation on the UART peripheral. + * @note The buffers are organized as uint8_t arrays for data sizes below + * or equal to 8 bits else it is organized as uint16_t arrays. + * + * @param[in] uartp pointer to the @p UARTDriver object + * @param[in] n number of data frames to send + * @param[out] rxbuf the pointer to the receive buffer + * + * @notapi + */ +void uart_lld_start_receive(UARTDriver *uartp, size_t n, void *rxbuf) { + + /* Stopping previous activity (idle state).*/ + dmaStreamDisable(uartp->dmarx); + dmaStreamClearInterrupt(uartp->dmarx); + + /* RX DMA channel preparation and start.*/ + dmaStreamSetMemory0(uartp->dmarx, rxbuf); + dmaStreamSetTransactionSize(uartp->dmarx, n); + dmaStreamSetMode(uartp->dmarx, uartp->dmamode | STM32_DMA_CR_DIR_P2M | + STM32_DMA_CR_MINC | STM32_DMA_CR_TEIE | + STM32_DMA_CR_TCIE); + dmaStreamEnable(uartp->dmarx); +} + +/** + * @brief Stops any ongoing receive operation. + * @note Stopping a receive operation also suppresses the receive callbacks. + * + * @param[in] uartp pointer to the @p UARTDriver object + * + * @return The number of data frames not received by the + * stopped receive operation. + * + * @notapi + */ +size_t uart_lld_stop_receive(UARTDriver *uartp) { + size_t n; + + dmaStreamDisable(uartp->dmarx); + dmaStreamClearInterrupt(uartp->dmarx); + n = dmaStreamGetTransactionSize(uartp->dmarx); + set_rx_idle_loop(uartp); + return n; +} + +#endif /* HAL_USE_UART */ + +/** @} */ -- cgit v1.2.3