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Diffstat (limited to 'os/hal/ports/MSP430X/hal_dma_lld.c')
-rw-r--r--os/hal/ports/MSP430X/hal_dma_lld.c253
1 files changed, 134 insertions, 119 deletions
diff --git a/os/hal/ports/MSP430X/hal_dma_lld.c b/os/hal/ports/MSP430X/hal_dma_lld.c
index 58293ca..43e1d6c 100644
--- a/os/hal/ports/MSP430X/hal_dma_lld.c
+++ b/os/hal/ports/MSP430X/hal_dma_lld.c
@@ -40,9 +40,8 @@
/* Driver local variables and types. */
/*===========================================================================*/
-/* TODO make sure this is right... */
-static msp430x_dma_ch_reg_t * const dma_channels = (msp430x_dma_ch_reg_t *)&DMA0CTL;
-static uint8_t * const dma_ctls = (uint8_t *)&DMACTL0;
+static msp430x_dma_ch_reg_t * const dma_channels =
+ (msp430x_dma_ch_reg_t *)&DMA0CTL;
static msp430x_dma_cb_t callbacks[MSP430X_DMA_CHANNELS];
#if CH_CFG_USE_SEMAPHORES
@@ -53,16 +52,29 @@ static semaphore_t dma_lock;
/* Driver local functions. */
/*===========================================================================*/
+/**
+ * @brief Set a DMA trigger using an index.
+ *
+ * @param[in] index The index of the DMA channel whose trigger is set.
+ * @param[in] trigger The trigger to use.
+ * @note This is all to get around weird MSP behavior when writing to memory-
+ * mapped registers using bytewise instructions.
+ */
+static void dma_trigger_set(uint8_t index, uint8_t trigger) {
+ uint16_t * ctl = ((uint16_t *)((uintptr_t)(&DMACTL0)) + (index / 2));
+ *ctl &= 0xFF00 >> (8 * (index % 2));
+ *ctl |= trigger << (8 * (index % 2));
+}
static void init_request(const msp430x_dma_req_t * request, uint8_t index) {
-
- dma_ctls[index] = request->trigger;
- callbacks[index] = request->callback;
- msp430x_dma_ch_reg_t * ch = &dma_channels[index];
- ch->sa = (uintptr_t)request->source_addr;
- ch->da = (uintptr_t)request->dest_addr;
- ch->sz = request->size;
- ch->ctl = DMAREQ | DMAIE | DMAEN | request->data_mode | request->addr_mode
- | request->transfer_mode;
+
+ dma_trigger_set(index, request->trigger);
+ callbacks[index] = request->callback;
+ msp430x_dma_ch_reg_t * ch = &dma_channels[index];
+ ch->sa = (uintptr_t)request->source_addr;
+ ch->da = (uintptr_t)request->dest_addr;
+ ch->sz = request->size;
+ ch->ctl = DMAREQ | DMAIE | DMAEN | request->data_mode | request->addr_mode |
+ request->transfer_mode;
}
/*===========================================================================*/
@@ -72,19 +84,22 @@ static void init_request(const msp430x_dma_req_t * request, uint8_t index) {
PORT_IRQ_HANDLER(DMA_VECTOR) {
uint8_t index;
OSAL_IRQ_PROLOGUE();
-
+
index = (DMAIV >> 1) - 1;
-
+
if (index < MSP430X_DMA_CHANNELS) {
+#if CH_CFG_USE_SEMAPHORES
+ chSemSignalI(&dma_lock);
+#endif
+
msp430x_dma_cb_t * cb = &callbacks[index];
-
+
/* WARNING: CALLBACKS ARE CALLED IN AN ISR CONTEXT! */
if (cb->callback != NULL) {
cb->callback(cb->args);
}
-
- }
-
+ }
+
OSAL_IRQ_EPILOGUE();
}
@@ -94,7 +109,7 @@ PORT_IRQ_HANDLER(DMA_VECTOR) {
/**
* @brief Initialize the DMA engine.
- *
+ *
* @init
*/
void dmaInit(void) {
@@ -112,132 +127,132 @@ void dmaInit(void) {
* disabled, the calling thread will busy-wait instead of sleeping.
*/
bool dmaRequest(msp430x_dma_req_t * request, systime_t timeout) {
- /* Check if a DMA channel is available */
+/* Check if a DMA channel is available */
#if CH_CFG_USE_SEMAPHORES
msg_t semresult = chSemWaitTimeout(&dma_lock, timeout);
if (semresult != MSG_OK)
return true;
#endif
-
+
#if !(CH_CFG_USE_SEMAPHORES)
systime_t start = chVTGetSystemTimeX();
-
+
do {
#endif
- /* Grab the correct DMA channel to use */
- int i = 0;
- for (i = 0; i < MSP430X_DMA_CHANNELS; i++) {
- if (!(dma_channels[i].ctl & DMAEN)) {
- break;
+ /* Grab the correct DMA channel to use */
+ int i = 0;
+ for (i = 0; i < MSP430X_DMA_CHANNELS; i++) {
+ if (!(dma_channels[i].ctl & DMAEN)) {
+ break;
+ }
}
- }
#if !(CH_CFG_USE_SEMAPHORES)
- while (chVTTimeElapsedSinceX(start) < timeout);
+ while (chVTTimeElapsedSinceX(start) < timeout)
+ ;
#endif
-
+
#if !(CH_CFG_USE_SEMAPHORES)
- if (i == MSP430X_DMA_CHANNELS) {
- return true;
- }
-#endif
-
- /* Make the request */
- init_request(request, i);
-
-#if CH_CFG_USE_SEMAPHORES
- chSemSignal(&dma_lock);
+ if (i == MSP430X_DMA_CHANNELS) {
+ return true;
+ }
#endif
-
- return false;
-}
-/**
- * @brief Acquires exclusive control of a DMA channel.
- * @pre The channel must not be already acquired or an error is returned.
- * @note If the channel is in use by the DMA engine, blocks until acquired.
- * @post This channel must be interacted with using only the functions
- * defined in this module.
- *
- * @param[out] channel The channel handle. Must be pre-allocated.
- * @param[in] index The index of the channel (< MSP430X_DMA_CHANNELS).
- * @return The operation status.
- * @retval false no error, channel acquired.
- * @retval true error, channel already acquired.
- */
-bool dmaAcquire(msp430x_dma_ch_t * channel, uint8_t index) {
- /* Acquire the channel in an idle mode */
-
- /* Is the channel already acquired? */
- osalDbgAssert(index < MSP430X_DMA_CHANNELS, "invalid channel index");
- if (dma_channels[index].ctl & DMADT_4) {
- return true;
+ /* Make the request */
+ init_request(request, i);
+
+ return false;
}
-
- /* Increment the DMA counter */
+
+ /**
+ * @brief Acquires exclusive control of a DMA channel.
+ * @pre The channel must not be already acquired or an error is returned.
+ * @note If the channel is in use by the DMA engine, blocks until acquired.
+ * @post This channel must be interacted with using only the functions
+ * defined in this module.
+ *
+ * @param[out] channel The channel handle. Must be pre-allocated.
+ * @param[in] index The index of the channel (< MSP430X_DMA_CHANNELS).
+ * @return The operation status.
+ * @retval false no error, channel acquired.
+ * @retval true error, channel already acquired.
+ */
+ bool dmaAcquire(msp430x_dma_ch_t * channel, uint8_t index) {
+ /* Acquire the channel in an idle mode */
+
+ /* Is the channel already acquired? */
+ osalDbgAssert(index < MSP430X_DMA_CHANNELS, "invalid channel index");
+ if (dma_channels[index].ctl & DMADT_4) {
+ return true;
+ }
+
+/* Increment the DMA counter */
#if CH_CFG_USE_SEMAPHORES
- msg_t semresult = chSemWait(&dma_lock);
- if (semresult != MSG_OK)
- return true;
+ msg_t semresult = chSemWait(&dma_lock);
+ if (semresult != MSG_OK)
+ return true;
#endif
-
- while (dma_channels[index].ctl & DMAEN) ;
-
- dma_ctls[index] = DMA_TRIGGER_MNEM(DMAREQ);
- dma_channels[index].sz = 0;
- dma_channels[index].ctl = DMAEN | DMAABORT | DMADT_4;
-
- channel->registers = dma_channels + index;
- channel->ctl = dma_ctls + index;
- channel->cb = callbacks + index;
-
- return false;
-}
-/**
- * @brief Initiates a DMA transfer operation using an acquired channel.
- * @pre The channel must have been acquired using @p dmaAcquire().
- *
- * @param[in] channel pointer to a DMA channel from @p dmaAcquire().
- * @param[in] request pointer to a DMA request object.
- */
-void dmaTransfer(msp430x_dma_ch_t * channel, msp430x_dma_req_t * request) {
-
- *(channel->ctl) = request->trigger;
-
+ while (dma_channels[index].ctl & DMAEN)
+ ;
+
+ dma_trigger_set(index, DMA_TRIGGER_MNEM(DMAREQ));
+ dma_channels[index].sz = 0;
+ dma_channels[index].ctl = DMAEN | DMAABORT | DMADT_4;
+
+ channel->registers = dma_channels + index;
+ channel->index = index;
+ channel->cb = callbacks + index;
+
+ return false;
+ }
+
+ /**
+ * @brief Initiates a DMA transfer operation using an acquired channel.
+ * @pre The channel must have been acquired using @p dmaAcquire().
+ *
+ * @param[in] channel pointer to a DMA channel from @p dmaAcquire().
+ * @param[in] request pointer to a DMA request object.
+ */
+ void dmaTransfer(msp430x_dma_ch_t * channel, msp430x_dma_req_t * request) {
+
+ dma_trigger_set(channel->index, request->trigger);
+ /**(channel->ctl) = request->trigger;*/
+
channel->cb->callback = request->callback.callback;
- channel->cb->args = request->callback.args;
-
+ channel->cb->args = request->callback.args;
+
chSysLock();
channel->registers->ctl &= (~DMAEN);
- channel->registers->sa = (uintptr_t)request->source_addr;
- channel->registers->da = (uintptr_t)request->dest_addr;
- channel->registers->sz = request->size;
- channel->registers->ctl = DMAIE | request->data_mode | request->addr_mode
- | request->transfer_mode | DMADT_4 | DMAEN | DMAREQ; /* repeated transfers */
+ channel->registers->sa = (uintptr_t)request->source_addr;
+ channel->registers->da = (uintptr_t)request->dest_addr;
+ channel->registers->sz = request->size;
+ channel->registers->ctl = DMAIE | request->data_mode | request->addr_mode |
+ request->transfer_mode | DMADT_4 | DMAEN |
+ DMAREQ; /* repeated transfers */
chSysUnlock();
-}
+ }
-/**
- * @brief Releases exclusive control of a DMA channel.
- * @details The channel is released from control and returned to the DMA engine
- * pool. Trying to release an unallocated channel is an illegal
- * operation and is trapped if assertions are enabled.
- * @pre The channel must have been acquired using @p dmaAcquire().
- * @post The channel is returned to the DMA engine pool.
- */
-void dmaRelease(msp430x_dma_ch_t * channel) {
-
- osalDbgCheck(channel != NULL);
- osalDbgAssert(channel->registers->ctl & DMADT_4, "not acquired");
-
- /* Release the channel in an idle mode */
- channel->registers->ctl = DMAABORT;
-
- /* release the DMA counter */
+ /**
+ * @brief Releases exclusive control of a DMA channel.
+ * @details The channel is released from control and returned to the DMA
+ * engine
+ * pool. Trying to release an unallocated channel is an illegal
+ * operation and is trapped if assertions are enabled.
+ * @pre The channel must have been acquired using @p dmaAcquire().
+ * @post The channel is returned to the DMA engine pool.
+ */
+ void dmaRelease(msp430x_dma_ch_t * channel) {
+
+ osalDbgCheck(channel != NULL);
+
+ /* Release the channel in an idle mode */
+ channel->registers->ctl = DMAABORT;
+
+/* release the DMA counter */
#if CH_CFG_USE_SEMAPHORES
- chSemSignal(&dma_lock);
+ chSemSignal(&dma_lock);
#endif
-}
+ }
#endif /* HAL_USE_DMA == TRUE */
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-03 20:56:06 +0000