diff options
Diffstat (limited to 'os/hal/ports/STM32F0xx/stm32_dma.c')
| -rw-r--r-- | os/hal/ports/STM32F0xx/stm32_dma.c | 291 |
1 files changed, 291 insertions, 0 deletions
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 */
+
+/** @} */
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