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/* Copyright (c) 2015, Atmel Corporation */
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/**
* \addtogroup usart_dma_module USART xDMA driver
* \section Usage
*
* <ul>
* <li> USARTD_Configure() initializes and configures the USART peripheral
* and xDMA for data transfer.</li>
* <li> Configures the parameters for the device corresponding to the cs
* value by USARTD_ConfigureCS(). </li>
* </ul>
*
*/
/**
* \file
*
* Implementation for the USART with xDMA driver.
*
*/
/*----------------------------------------------------------------------------
* Headers
*----------------------------------------------------------------------------*/
#include "chip.h"
#include "string.h"
#include "stdlib.h"
/*----------------------------------------------------------------------------
* Local functions
*----------------------------------------------------------------------------*/
/**
* \brief USART xDMA Rx callback
* Invoked on USART DMA reception done.
* \param channel DMA channel.
* \param pArg Pointer to callback argument - Pointer to USARTDma instance.
*/
static void USARTD_Rx_Cb(uint32_t channel, UsartDma *pArg)
{
UsartChannel *pUsartdCh = pArg->pRxChannel;
if (channel != pUsartdCh->ChNum)
return;
/* Release the DMA channels */
XDMAD_FreeChannel(pArg->pXdmad, pUsartdCh->ChNum);
pUsartdCh->dmaProgress = 1;
SCB_InvalidateDCache_by_Addr((uint32_t *)pUsartdCh->pBuff, pUsartdCh->BuffSize);
}
/**
* \brief USART xDMA Rx callback
* Invoked on USART DMA reception done.
* \param channel DMA channel.
* \param pArg Pointer to callback argument - Pointer to USARTDma instance.
*/
static void USARTD_Tx_Cb(uint32_t channel, UsartDma *pArg)
{
UsartChannel *pUsartdCh = pArg->pTxChannel;
if (channel != pUsartdCh->ChNum)
return;
/* Release the DMA channels */
XDMAD_FreeChannel(pArg->pXdmad, pUsartdCh->ChNum);
pUsartdCh->dmaProgress = 1;
}
/**
* \brief Configure the USART Rx DMA Destination with Linker List mode.
*
* \param UsartChannel Pointer to USART dma channel
* \returns 0 if the dma multibuffer configuration successfully; otherwise
* returnsUSARTD_ERROR_XXX.
*/
static uint8_t _configureRxDma(UsartDma *pUsart, UsartChannel *pUsartRx)
{
sXdmadCfg xdmadRxCfg;
uint32_t xdmaCndc, xdmaInt;
uint32_t i, LLI_Size;
Usart *pUsartHwRx = pUsart->pUsartHw;
sXdmad *pXdmadRx = pUsart->pXdmad;
uint8_t *pBuff = 0;
/* Setup RX Single block */
if (pUsartRx->dmaProgrammingMode < XDMAD_LLI) {
xdmadRxCfg.mbr_ubc = pUsartRx->BuffSize;
xdmadRxCfg.mbr_da = (uint32_t)pUsartRx->pBuff;
xdmadRxCfg.mbr_sa = (uint32_t)&pUsartHwRx->US_RHR;
xdmadRxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
XDMAC_CC_MBSIZE_SIXTEEN |
XDMAC_CC_DSYNC_PER2MEM |
XDMAC_CC_CSIZE_CHK_1 |
XDMAC_CC_DWIDTH_BYTE |
XDMAC_CC_SIF_AHB_IF1 |
XDMAC_CC_DIF_AHB_IF1 |
XDMAC_CC_SAM_FIXED_AM |
XDMAC_CC_DAM_INCREMENTED_AM |
XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
(pUsart->usartId, XDMAD_TRANSFER_RX));
xdmadRxCfg.mbr_bc = 0;
if (pUsartRx->dmaProgrammingMode == XDMAD_MULTI)
xdmadRxCfg.mbr_bc = pUsartRx->dmaBlockSize;
xdmadRxCfg.mbr_sus = 0;
xdmadRxCfg.mbr_dus = 0;
xdmaCndc = 0;
xdmaInt = (XDMAC_CIE_BIE |
XDMAC_CIE_DIE |
XDMAC_CIE_FIE |
XDMAC_CIE_RBIE |
XDMAC_CIE_WBIE |
XDMAC_CIE_ROIE);
} else if (pUsartRx->dmaProgrammingMode == XDMAD_LLI) {
/* Setup RX Link List */
LLI_Size = pUsartRx->dmaBlockSize;
pBuff = pUsartRx->pBuff;
if (pUsartRx->pLLIview != NULL) {
free(pUsartRx->pLLIview);
pUsartRx->pLLIview = NULL;
}
pUsartRx->pLLIview = malloc(sizeof(LinkedListDescriporView1) * LLI_Size);
if (pUsartRx->pLLIview == NULL) {
TRACE_ERROR(" Can not allocate memory to Rx LLI");
return USARTD_ERROR;
}
xdmadRxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
XDMAC_CC_MBSIZE_SIXTEEN |
XDMAC_CC_DSYNC_PER2MEM |
XDMAC_CC_MEMSET_NORMAL_MODE |
XDMAC_CC_CSIZE_CHK_1 |
XDMAC_CC_DWIDTH_BYTE |
XDMAC_CC_SIF_AHB_IF1 |
XDMAC_CC_DIF_AHB_IF1 |
XDMAC_CC_SAM_FIXED_AM |
XDMAC_CC_DAM_INCREMENTED_AM |
XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
(pUsart->usartId, XDMAD_TRANSFER_RX));
xdmadRxCfg.mbr_bc = 0;
for (i = 0; i < LLI_Size; i++) {
pUsartRx->pLLIview[i].mbr_ubc = XDMA_UBC_NVIEW_NDV1 |
XDMA_UBC_NSEN_UNCHANGED |
XDMA_UBC_NDEN_UPDATED |
((i == LLI_Size - 1) ? (
(pUsartRx->dmaRingBuffer) ?
XDMA_UBC_NDE_FETCH_EN : 0) :
XDMA_UBC_NDE_FETCH_EN) |
pUsartRx->BuffSize;
pUsartRx->pLLIview[i].mbr_sa = (uint32_t)&pUsartHwRx->US_RHR;
pUsartRx->pLLIview[i].mbr_da = (uint32_t)pBuff;
pUsartRx->pLLIview[i].mbr_nda = (i == (LLI_Size - 1)) ?
((pUsartRx->dmaRingBuffer) ? (uint32_t)pUsartRx->pLLIview : 0)
: (uint32_t)&pUsartRx->pLLIview[ i + 1 ];
pBuff += pUsartRx->BuffSize;
}
SCB_CleanDCache_by_Addr((uint32_t *)(pUsartRx->pLLIview),
sizeof(LinkedListDescriporView1)*LLI_Size);
xdmaCndc = XDMAC_CNDC_NDVIEW_NDV1 |
XDMAC_CNDC_NDE_DSCR_FETCH_EN |
XDMAC_CNDC_NDSUP_SRC_PARAMS_UPDATED |
XDMAC_CNDC_NDDUP_DST_PARAMS_UPDATED;
xdmaInt = ((pUsartRx->dmaRingBuffer) ? XDMAC_CIE_BIE : XDMAC_CIE_LIE);
} else
return 1;
if (XDMAD_ConfigureTransfer(
pXdmadRx, pUsartRx->ChNum, &xdmadRxCfg, xdmaCndc,
(uint32_t)pUsartRx->pLLIview, xdmaInt))
return USARTD_ERROR;
return 0;
}
/**
* \brief Configure the USART tx DMA source with Linker List mode.
*
* \param UsartChannel Pointer to USART dma channel
* \returns 0 if the dma multibuffer configuration successfully; otherwise returns
* USARTD_ERROR_XXX.
*/
static uint8_t _configureTxDma(UsartDma *pUsart, UsartChannel *pUsartTx)
{
sXdmadCfg xdmadTxCfg;
uint32_t xdmaCndc, xdmaInt, LLI_Size, i;
uint8_t *pBuff = 0;
Usart *pUsartHwTx = pUsart->pUsartHw;
sXdmad *pXdmadTx = pUsart->pXdmad;
/* Setup TX Link List */
if (pUsartTx->dmaProgrammingMode < XDMAD_LLI) {
/* Number of Data */
xdmadTxCfg.mbr_ubc = pUsartTx->BuffSize;
/* Source and Destination address of DMA */
xdmadTxCfg.mbr_sa = (uint32_t)pUsartTx->pBuff;
xdmadTxCfg.mbr_da = (uint32_t)&pUsartHwTx->US_THR;
/* DMA Channel configuration */
xdmadTxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
XDMAC_CC_MBSIZE_SIXTEEN |
XDMAC_CC_DSYNC_MEM2PER |
XDMAC_CC_CSIZE_CHK_1 |
XDMAC_CC_DWIDTH_BYTE |
XDMAC_CC_SIF_AHB_IF1 |
XDMAC_CC_DIF_AHB_IF1 |
XDMAC_CC_SAM_INCREMENTED_AM |
XDMAC_CC_DAM_FIXED_AM |
XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
(pUsart->usartId, XDMAD_TRANSFER_TX));
xdmadTxCfg.mbr_bc = 0;
if (pUsartTx->dmaProgrammingMode == XDMAD_MULTI)
xdmadTxCfg.mbr_bc = pUsartTx->dmaBlockSize;
xdmadTxCfg.mbr_sus = 0;
xdmadTxCfg.mbr_dus = 0;
xdmadTxCfg.mbr_ds = 0;
xdmaCndc = 0;
/* Enable End of Block; Read Bus error; Write Bus Error;
Overflow Error interrupt */
xdmaInt = (XDMAC_CIE_BIE |
XDMAC_CIE_RBIE |
XDMAC_CIE_WBIE |
XDMAC_CIE_ROIE);
} else if (pUsartTx->dmaProgrammingMode == XDMAD_LLI) {
LLI_Size = pUsartTx->dmaBlockSize;
pBuff = pUsartTx->pBuff;
/* If channel's LLI is already configured and application
want to reconfigured it, free before re-allocating memory */
if (pUsartTx->pLLIview != NULL) {
free(pUsartTx->pLLIview);
pUsartTx->pLLIview = NULL;
}
pUsartTx->pLLIview = malloc(sizeof(LinkedListDescriporView1) * LLI_Size);
if (pUsartTx->pLLIview == NULL) {
TRACE_ERROR(" Can not allocate memory to Tx LLI");
return USARTD_ERROR;
}
xdmadTxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
XDMAC_CC_MBSIZE_SIXTEEN |
XDMAC_CC_DSYNC_MEM2PER |
XDMAC_CC_MEMSET_NORMAL_MODE |
XDMAC_CC_CSIZE_CHK_1 |
XDMAC_CC_DWIDTH_BYTE |
XDMAC_CC_SIF_AHB_IF1 |
XDMAC_CC_DIF_AHB_IF1 |
XDMAC_CC_SAM_INCREMENTED_AM |
XDMAC_CC_DAM_FIXED_AM |
XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
(pUsart->usartId, XDMAD_TRANSFER_TX));
xdmadTxCfg.mbr_bc = 0;
for (i = 0; i < LLI_Size; i++) {
pUsartTx->pLLIview[i].mbr_ubc = XDMA_UBC_NVIEW_NDV1 |
XDMA_UBC_NSEN_UPDATED |
XDMA_UBC_NDEN_UNCHANGED |
((i == LLI_Size - 1) ? ((pUsartTx->dmaRingBuffer)
? XDMA_UBC_NDE_FETCH_EN : 0) :
XDMA_UBC_NDE_FETCH_EN) | pUsartTx->BuffSize;
pUsartTx->pLLIview[i].mbr_sa = (uint32_t)pBuff;
pUsartTx->pLLIview[i].mbr_da = (uint32_t)&pUsartHwTx->US_THR;
pUsartTx->pLLIview[i].mbr_nda = (i == (LLI_Size - 1)) ?
((pUsartTx->dmaRingBuffer) ? (uint32_t)pUsartTx->pLLIview : 0)
: (uint32_t)&pUsartTx->pLLIview[ i + 1 ];
pBuff += pUsartTx->BuffSize;
}
SCB_CleanDCache_by_Addr((uint32_t *)(pUsartTx->pLLIview),
sizeof(LinkedListDescriporView1)*LLI_Size);
xdmaCndc = XDMAC_CNDC_NDVIEW_NDV1 |
XDMAC_CNDC_NDE_DSCR_FETCH_EN |
XDMAC_CNDC_NDSUP_SRC_PARAMS_UPDATED |
XDMAC_CNDC_NDDUP_DST_PARAMS_UPDATED;
xdmaInt = ((pUsartTx->dmaRingBuffer) ? XDMAC_CIE_BIE : XDMAC_CIE_LIE);
} else {
TRACE_ERROR("DmaProgState is incorrect \n\r");
return 1;
}
if (XDMAD_ConfigureTransfer(pXdmadTx, pUsartTx->ChNum,
&xdmadTxCfg, xdmaCndc, (uint32_t)pUsartTx->pLLIview, xdmaInt))
return USARTD_ERROR;
return 0;
}
/*----------------------------------------------------------------------------
* Exported functions
*----------------------------------------------------------------------------*/
/**
* \brief Initializes the USARTDma structure and the corresponding USART & DMA .
* hardware select value.
* The driver will uses DMA channel 0 for RX and DMA channel 1 for TX.
* The DMA channels are freed automatically when no USART command processing.
*
* \param pUSARTD Pointer to a UsartDma instance.
* \param pUsartHw Associated USART peripheral.
* \param usartId USART peripheral identifier.
* \param UsartClk USART clock.
* \param pXdmad Pointer to a Dmad instance.
*/
uint32_t USARTD_Configure(UsartDma *pUsartd ,
uint8_t usartId,
uint32_t UsartMode,
uint32_t BaudRate,
uint32_t UsartClk)
{
/* Enable the peripheral clock in the PMC*/
PMC_EnablePeripheral(usartId);
/* Initialize the USART structure */
pUsartd->usartId = usartId;
if (usartId == ID_USART0)
pUsartd->pUsartHw = USART0;
if (usartId == ID_USART1)
pUsartd->pUsartHw = USART1;
if (usartId == ID_USART2)
pUsartd->pUsartHw = USART2;
pUsartd->pXdmad->pXdmacs = XDMAC;
/* Enable the USART Peripheral ,Execute a software reset of the USART,
Configure USART in Master Mode*/
USART_Configure (pUsartd->pUsartHw, UsartMode, BaudRate, UsartClk);
/* Driver initialize */
XDMAD_Initialize(pUsartd->pXdmad, 0);
/* Check if DMA IRQ is enable; if not clear pending IRQs in init it */
if (!(NVIC_GetActive(XDMAC_IRQn)))
NVIC_ClearPendingIRQ(XDMAC_IRQn);
return 0;
}
/**
* \brief This function initialize the appropriate DMA channel for Rx channel
* of USART
* \param pUsartd Pointer to a UsartDma instance.
* \param pRxCh Pointer to TxChannel configuration
* \returns 0 if the transfer has been started successfully;
* otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
* USARTD_ERROR if the command is not valid.
*/
uint32_t USARTD_EnableRxChannels(UsartDma *pUsartd, UsartChannel *pRxCh)
{
uint32_t Channel;
assert(pRxCh);
/* Init USART Rx Channel. */
pUsartd->pRxChannel = pRxCh;
/* Enables the USART to receive data. */
USART_SetReceiverEnabled (pUsartd->pUsartHw , ENABLE);
/* Allocate a DMA channel for USART0/1 RX. */
Channel = XDMAD_AllocateChannel(pUsartd->pXdmad, pUsartd->usartId,
XDMAD_TRANSFER_MEMORY);
if (Channel == XDMAD_ALLOC_FAILED)
return USARTD_ERROR;
pRxCh->ChNum = Channel;
/* Setup callbacks for USART RX */
if (pUsartd->pRxChannel->callback) {
XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum,
(XdmadTransferCallback)pRxCh->callback, pRxCh->pArgument);
} else {
XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum,
(XdmadTransferCallback)USARTD_Rx_Cb, pUsartd);
}
if (XDMAD_PrepareChannel(pUsartd->pXdmad, pRxCh->ChNum))
return USARTD_ERROR;
if (_configureRxDma(pUsartd , pUsartd->pRxChannel))
return USARTD_ERROR_LOCK;
/* Check if DMA IRQ is enable; if not Enable it */
if (!(NVIC_GetActive(XDMAC_IRQn))) {
/* Enable interrupt */
NVIC_EnableIRQ(XDMAC_IRQn);
}
return 0;
}
/**
* \brief This function initialize the appropriate DMA channel for Tx channel
* of USART
* \param pUsartd Pointer to a USARTDma instance.
* \param pTxCh Pointer to TxChannel configuration
* \returns 0 if the transfer has been started successfully;
* otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
* USARTD_ERROR if the command is not valid.
*/
uint32_t USARTD_EnableTxChannels(UsartDma *pUsartd, UsartChannel *pTxCh)
{
uint32_t Channel;
assert(pTxCh);
/* Init USART Tx Channel. */
pUsartd->pTxChannel = pTxCh;
/* Enables the USART to transfer data. */
USART_SetTransmitterEnabled (pUsartd->pUsartHw , ENABLE);
/* Allocate a DMA channel for USART0/1 TX. */
Channel = XDMAD_AllocateChannel(pUsartd->pXdmad, XDMAD_TRANSFER_MEMORY,
pUsartd->usartId);
if (Channel == XDMAD_ALLOC_FAILED)
return USARTD_ERROR;
pTxCh->ChNum = Channel;
/* Setup callbacks for USART0/1 TX */
if (pUsartd->pTxChannel->callback) {
XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum,
(XdmadTransferCallback)pTxCh->callback, pTxCh->pArgument);
} else
XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum,
(XdmadTransferCallback)USARTD_Tx_Cb, pUsartd);
if (XDMAD_PrepareChannel(pUsartd->pXdmad, pTxCh->ChNum))
return USARTD_ERROR;
if (_configureTxDma(pUsartd , pUsartd->pTxChannel))
return USARTD_ERROR_LOCK;
/* Check if DMA IRQ is enable; if not Enable it */
if (!(NVIC_GetActive(XDMAC_IRQn))) {
/* Enable interrupt */
NVIC_EnableIRQ(XDMAC_IRQn);
}
return 0;
}
/**
* \brief This function disables the appropriate DMA channel for Rx channel of
* USART
* \param pUsartd Pointer to a UsartDma instance.
* \param pRxCh Pointer to TxChannel configuration
* \returns 0 if the transfer has been started successfully;
* otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
* USARTD_ERROR if the command is not valid.
*/
uint32_t USARTD_DisableRxChannels(UsartDma *pUsartd, UsartChannel *pRxCh)
{
assert(pRxCh);
/* Enables the USART to transfer data. */
USART_SetReceiverEnabled (pUsartd->pUsartHw , DISABLE);
XDMAD_StopTransfer(pUsartd->pXdmad, pRxCh->ChNum);
XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum, NULL, NULL);
/* Free allocated DMA channel for USART TX. */
if (XDMAD_FreeChannel(pUsartd->pXdmad, pRxCh->ChNum) != XDMAD_OK)
return USARTD_ERROR;
if (pRxCh->dmaProgrammingMode == XDMAD_LLI) {
free(pRxCh->pLLIview);
pRxCh->pLLIview = NULL;
}
pRxCh->dmaProgress = 1;
return 0;
}
/**
* \brief This function disables the appropriate DMA channel for Tx channel of
* USART
* \param pUsartd Pointer to a USARTDma instance.
* \param pTxCh Pointer to TxChannel configuration
* \returns 0 if the transfer has been started successfully;
* otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
* USARTD_ERROR if the command is not valid.
*/
uint32_t USARTD_DisableTxChannels(UsartDma *pUsartd, UsartChannel *pTxCh)
{
assert(pTxCh);
/* Enables the USART to transfer data. */
USART_SetTransmitterEnabled (pUsartd->pUsartHw , DISABLE);
XDMAD_StopTransfer(pUsartd->pXdmad, pTxCh->ChNum);
XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum, NULL, NULL);
/* Free allocated DMA channel for USART TX. */
if (XDMAD_FreeChannel(pUsartd->pXdmad, pTxCh->ChNum) != XDMAD_OK)
return USARTD_ERROR;
if (pTxCh->dmaProgrammingMode == XDMAD_LLI) {
free(pTxCh->pLLIview);
pTxCh->pLLIview = NULL;
}
pTxCh->dmaProgress = 1;
return 0;
}
/**
* \brief Starts a USART master transfer. This is a non blocking function. It
* will return as soon as the transfer is started.
*
* \param pUSARTD Pointer to a USARTDma instance.
* \returns 0 if the transfer has been started successfully; otherwise returns
* USARTD_ERROR_LOCK is the driver is in use, or USARTD_ERROR if the command is
* not valid.
*/
uint32_t USARTD_SendData(UsartDma *pUsartd)
{
/* Start DMA 0(RX) && 1(TX) */
pUsartd->pTxChannel->dmaProgress = 0;
SCB_CleanDCache_by_Addr((uint32_t *)pUsartd->pTxChannel->pBuff,
pUsartd->pTxChannel->BuffSize);
if (XDMAD_StartTransfer(pUsartd->pXdmad, pUsartd->pTxChannel->ChNum))
return USARTD_ERROR_LOCK;
return 0;
}
/**
* \brief Starts a USART master transfer. This is a non blocking function. It will
* return as soon as the transfer is started.
*
* \param pUSARTD Pointer to a USARTDma instance.
* \returns 0 if the transfer has been started successfully; otherwise returns
* USARTD_ERROR_LOCK is the driver is in use, or USARTD_ERROR if the command is not
* valid.
*/
uint32_t USARTD_RcvData(UsartDma *pUsartd)
{
/* Start DMA 0(RX) && 1(TX) */
pUsartd->pRxChannel->dmaProgress = 0;
if (XDMAD_StartTransfer(pUsartd->pXdmad, pUsartd->pRxChannel->ChNum))
return USARTD_ERROR_LOCK;
return 0;
}