From 74b860fee65ca8feb2a796144976ff6c44e64bcc Mon Sep 17 00:00:00 2001 From: gdisirio Date: Mon, 2 Sep 2013 09:48:38 +0000 Subject: git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6242 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/hal/ports/STM32F0xx/stm32_dma.c | 291 +++++++++++++++++++++++++++++++++++++ 1 file changed, 291 insertions(+) create mode 100644 os/hal/ports/STM32F0xx/stm32_dma.c (limited to 'os/hal/ports/STM32F0xx/stm32_dma.c') diff --git a/os/hal/ports/STM32F0xx/stm32_dma.c b/os/hal/ports/STM32F0xx/stm32_dma.c new file mode 100644 index 000000000..623c9d11b --- /dev/null +++ b/os/hal/ports/STM32F0xx/stm32_dma.c @@ -0,0 +1,291 @@ +/* + ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +*/ + +/** + * @file STM32F0xx/stm32_dma.c + * @brief DMA helper driver code. + * + * @addtogroup STM32F0xx_DMA + * @details DMA sharing helper driver. In the STM32 the DMA streams are a + * shared resource, this driver allows to allocate and free DMA + * streams at runtime in order to allow all the other device + * drivers to coordinate the access to the resource. + * @note The DMA ISR handlers are all declared into this module because + * sharing, the various device drivers can associate a callback to + * ISRs when allocating streams. + * @{ + */ + +#include "hal.h" + +/* The following macro is only defined if some driver requiring DMA services + has been enabled.*/ +#if defined(STM32_DMA_REQUIRED) || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver local definitions. */ +/*===========================================================================*/ + +/** + * @brief Mask of the DMA1 streams in @p dma_streams_mask. + */ +#define STM32_DMA1_STREAMS_MASK 0x0000007F + +/** + * @brief Mask of the DMA2 streams in @p dma_streams_mask. + */ +#define STM32_DMA2_STREAMS_MASK 0x00000F80 + +/** + * @brief Post-reset value of the stream CCR register. + */ +#define STM32_DMA_CCR_RESET_VALUE 0x00000000 + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +/** + * @brief DMA streams descriptors. + * @details This table keeps the association between an unique stream + * identifier and the involved physical registers. + * @note Don't use this array directly, use the appropriate wrapper macros + * instead: @p STM32_DMA1_STREAM1, @p STM32_DMA1_STREAM2 etc. + */ +const stm32_dma_stream_t _stm32_dma_streams[STM32_DMA_STREAMS] = { + {DMA1_Channel1, &DMA1->IFCR, 0, 0, DMA1_Channel1_IRQn}, + {DMA1_Channel2, &DMA1->IFCR, 4, 1, DMA1_Channel2_3_IRQn}, + {DMA1_Channel3, &DMA1->IFCR, 8, 2, DMA1_Channel2_3_IRQn}, + {DMA1_Channel4, &DMA1->IFCR, 12, 3, DMA1_Channel4_5_IRQn}, + {DMA1_Channel5, &DMA1->IFCR, 16, 4, DMA1_Channel4_5_IRQn} +}; + +/*===========================================================================*/ +/* Driver local variables and types. */ +/*===========================================================================*/ + +/** + * @brief DMA ISR redirector type. + */ +typedef struct { + stm32_dmaisr_t dma_func; /**< @brief DMA callback function. */ + void *dma_param; /**< @brief DMA callback parameter. */ +} dma_isr_redir_t; + +/** + * @brief Mask of the allocated streams. + */ +static uint32_t dma_streams_mask; + +/** + * @brief DMA IRQ redirectors. + */ +static dma_isr_redir_t dma_isr_redir[STM32_DMA_STREAMS]; + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver interrupt handlers. */ +/*===========================================================================*/ + +/** + * @brief DMA1 stream 1 shared interrupt handler. + * + * @isr + */ +OSAL_IRQ_HANDLER(Vector64) { + uint32_t flags; + + OSAL_IRQ_PROLOGUE(); + + flags = (DMA1->ISR >> 0) & STM32_DMA_ISR_MASK; + DMA1->IFCR = STM32_DMA_ISR_MASK << 0; + if (dma_isr_redir[0].dma_func) + dma_isr_redir[0].dma_func(dma_isr_redir[0].dma_param, flags); + + OSAL_IRQ_EPILOGUE(); +} + +/** + * @brief DMA1 streams 2 and 3 shared interrupt handler. + * + * @isr + */ +OSAL_IRQ_HANDLER(Vector68) { + uint32_t flags; + + OSAL_IRQ_PROLOGUE(); + + /* Check on channel 2.*/ + flags = (DMA1->ISR >> 4) & STM32_DMA_ISR_MASK; + if (flags & STM32_DMA_ISR_MASK) { + DMA1->IFCR = STM32_DMA_ISR_MASK << 4; + if (dma_isr_redir[1].dma_func) + dma_isr_redir[1].dma_func(dma_isr_redir[1].dma_param, flags); + } + + /* Check on channel 3.*/ + flags = (DMA1->ISR >> 8) & STM32_DMA_ISR_MASK; + if (flags & STM32_DMA_ISR_MASK) { + DMA1->IFCR = STM32_DMA_ISR_MASK << 8; + if (dma_isr_redir[2].dma_func) + dma_isr_redir[2].dma_func(dma_isr_redir[2].dma_param, flags); + } + + OSAL_IRQ_EPILOGUE(); +} + +/** + * @brief DMA1 streams 4 and 5 shared interrupt handler. + * + * @isr + */ +OSAL_IRQ_HANDLER(Vector6C) { + uint32_t flags; + + OSAL_IRQ_PROLOGUE(); + + /* Check on channel 4.*/ + flags = (DMA1->ISR >> 12) & STM32_DMA_ISR_MASK; + if (flags & STM32_DMA_ISR_MASK) { + DMA1->IFCR = STM32_DMA_ISR_MASK << 12; + if (dma_isr_redir[3].dma_func) + dma_isr_redir[3].dma_func(dma_isr_redir[3].dma_param, flags); + } + + /* Check on channel 5.*/ + flags = (DMA1->ISR >> 16) & STM32_DMA_ISR_MASK; + if (flags & STM32_DMA_ISR_MASK) { + DMA1->IFCR = STM32_DMA_ISR_MASK << 16; + if (dma_isr_redir[4].dma_func) + dma_isr_redir[4].dma_func(dma_isr_redir[4].dma_param, flags); + } + + OSAL_IRQ_EPILOGUE(); +} + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief STM32 DMA helper initialization. + * + * @init + */ +void dmaInit(void) { + int i; + + dma_streams_mask = 0; + for (i = 0; i < STM32_DMA_STREAMS; i++) { + _stm32_dma_streams[i].channel->CCR = 0; + dma_isr_redir[i].dma_func = NULL; + } + DMA1->IFCR = 0xFFFFFFFF; +} + +/** + * @brief Allocates a DMA stream. + * @details The stream is allocated and, if required, the DMA clock enabled. + * The function also enables the IRQ vector associated to the stream + * and initializes its priority. + * @pre The stream must not be already in use or an error is returned. + * @post The stream is allocated and the default ISR handler redirected + * to the specified function. + * @post The stream ISR vector is enabled and its priority configured. + * @post The stream must be freed using @p dmaStreamRelease() before it can + * be reused with another peripheral. + * @post The stream is in its post-reset state. + * @note This function can be invoked in both ISR or thread context. + * + * @param[in] dmastp pointer to a stm32_dma_stream_t structure + * @param[in] priority IRQ priority mask for the DMA stream + * @param[in] func handling function pointer, can be @p NULL + * @param[in] param a parameter to be passed to the handling function + * @return The operation status. + * @retval FALSE no error, stream taken. + * @retval TRUE error, stream already taken. + * + * @special + */ +bool_t dmaStreamAllocate(const stm32_dma_stream_t *dmastp, + uint32_t priority, + stm32_dmaisr_t func, + void *param) { + + osalDbgCheck(dmastp != NULL); + + /* Checks if the stream is already taken.*/ + if ((dma_streams_mask & (1 << dmastp->selfindex)) != 0) + return TRUE; + + /* Marks the stream as allocated.*/ + dma_isr_redir[dmastp->selfindex].dma_func = func; + dma_isr_redir[dmastp->selfindex].dma_param = param; + dma_streams_mask |= (1 << dmastp->selfindex); + + /* Enabling DMA clocks required by the current streams set.*/ + if ((dma_streams_mask & STM32_DMA1_STREAMS_MASK) != 0) + rccEnableDMA1(FALSE); + + /* Putting the stream in a safe state.*/ + dmaStreamDisable(dmastp); + dmastp->channel->CCR = STM32_DMA_CCR_RESET_VALUE; + + /* Enables the associated IRQ vector if a callback is defined.*/ + if (func != NULL) + nvicEnableVector(dmastp->vector, priority); + + return FALSE; +} + +/** + * @brief Releases a DMA stream. + * @details The stream is freed and, if required, the DMA clock disabled. + * Trying to release a unallocated stream is an illegal operation + * and is trapped if assertions are enabled. + * @pre The stream must have been allocated using @p dmaStreamAllocate(). + * @post The stream is again available. + * @note This function can be invoked in both ISR or thread context. + * + * @param[in] dmastp pointer to a stm32_dma_stream_t structure + * + * @special + */ +void dmaStreamRelease(const stm32_dma_stream_t *dmastp) { + + osalDbgCheck(dmastp != NULL); + + /* Check if the streams is not taken.*/ + osalDbgAssert((dma_streams_mask & (1 << dmastp->selfindex)) != 0, + "not allocated"); + + /* Disables the associated IRQ vector.*/ + nvicDisableVector(dmastp->vector); + + /* Marks the stream as not allocated.*/ + dma_streams_mask &= ~(1 << dmastp->selfindex); + + /* Shutting down clocks that are no more required, if any.*/ + if ((dma_streams_mask & STM32_DMA1_STREAMS_MASK) == 0) + rccDisableDMA1(FALSE); +} + +#endif /* STM32_DMA_REQUIRED */ + +/** @} */ -- cgit v1.2.3