Overview

The MCUXpresso SDK provides a peripheral driver for the Direct Memory Access (DMA) of MCUXpresso SDK devices.

Typical use case

DMA Operation

dma_transfer_config_t transferConfig;
uint32_t transferDone = false;
DMA_Init(DMA0);
DMA_CreateHandle(&g_DMA_Handle, DMA0, channel);
DMA_InstallCallback(&g_DMA_Handle, DMA_Callback, &transferDone);
DMA_PrepareTransfer(&transferConfig, srcAddr, srcWidth, destAddr, destWidth, transferBytes,
                    kDMA_MemoryToMemory);
DMA_SubmitTransfer(&g_DMA_Handle, &transferConfig, true);
DMA_StartTransfer(&g_DMA_Handle);
/* Wait for DMA transfer finish */
while (transferDone != true);

Data Structures
struct	dma_transfer_config_t
	DMA transfer configuration structure. More...

struct	dma_channel_link_config_t
	DMA transfer configuration structure. More...

struct	dma_handle_t
	DMA DMA handle structure. More...

Typedefs
typedef void(*	dma_callback )(struct _dma_handle handle, void userData)
	Callback function prototype for the DMA driver. More...

Enumerations
enum	_dma_channel_status_flags { kDMA_TransactionsBCRFlag = DMA_DSR_BCR_BCR_MASK, kDMA_TransactionsDoneFlag = DMA_DSR_BCR_DONE_MASK, kDMA_TransactionsBusyFlag = DMA_DSR_BCR_BSY_MASK, kDMA_TransactionsRequestFlag = DMA_DSR_BCR_REQ_MASK, kDMA_BusErrorOnDestinationFlag = DMA_DSR_BCR_BED_MASK, kDMA_BusErrorOnSourceFlag = DMA_DSR_BCR_BES_MASK, kDMA_ConfigurationErrorFlag = DMA_DSR_BCR_CE_MASK }
	status flag for the DMA driver. More...

enum	dma_transfer_size_t { kDMA_Transfersize32bits = 0x0U, kDMA_Transfersize8bits, kDMA_Transfersize16bits }
	DMA transfer size type. More...

enum	dma_modulo_t { kDMA_ModuloDisable = 0x0U, kDMA_Modulo16Bytes, kDMA_Modulo32Bytes, kDMA_Modulo64Bytes, kDMA_Modulo128Bytes, kDMA_Modulo256Bytes, kDMA_Modulo512Bytes, kDMA_Modulo1KBytes, kDMA_Modulo2KBytes, kDMA_Modulo4KBytes, kDMA_Modulo8KBytes, kDMA_Modulo16KBytes, kDMA_Modulo32KBytes, kDMA_Modulo64KBytes, kDMA_Modulo128KBytes, kDMA_Modulo256KBytes }
	Configuration type for the DMA modulo. More...

enum	dma_channel_link_type_t { kDMA_ChannelLinkDisable = 0x0U, kDMA_ChannelLinkChannel1AndChannel2, kDMA_ChannelLinkChannel1, kDMA_ChannelLinkChannel1AfterBCR0 }
	DMA channel link type. More...

enum	dma_transfer_type_t { kDMA_MemoryToMemory = 0x0U, kDMA_PeripheralToMemory, kDMA_MemoryToPeripheral }
	DMA transfer type. More...

enum	dma_transfer_options_t { kDMA_NoOptions = 0x0U, kDMA_EnableInterrupt }
	DMA transfer options. More...

enum	_dma_transfer_status
	DMA transfer status.

Driver version
#define	FSL_DMA_DRIVER_VERSION (MAKE_VERSION(2, 0, 1))
	DMA driver version 2.0.1. More...

DMA Initialization and De-initialization
void	DMA_Init (DMA_Type *base)
	Initializes the DMA peripheral. More...

void	DMA_Deinit (DMA_Type *base)
	Deinitializes the DMA peripheral. More...

DMA Channel Operation
void	DMA_ResetChannel (DMA_Type *base, uint32_t channel)
	Resets the DMA channel. More...

void	DMA_SetTransferConfig (DMA_Type base, uint32_t channel, const dma_transfer_config_t config)
	Configures the DMA transfer attribute. More...

void	DMA_SetChannelLinkConfig (DMA_Type base, uint32_t channel, const dma_channel_link_config_t config)
	Configures the DMA channel link feature. More...

static void	DMA_SetSourceAddress (DMA_Type *base, uint32_t channel, uint32_t srcAddr)
	Sets the DMA source address for the DMA transfer. More...

static void	DMA_SetDestinationAddress (DMA_Type *base, uint32_t channel, uint32_t destAddr)
	Sets the DMA destination address for the DMA transfer. More...

static void	DMA_SetTransferSize (DMA_Type *base, uint32_t channel, uint32_t size)
	Sets the DMA transfer size for the DMA transfer. More...

void	DMA_SetModulo (DMA_Type *base, uint32_t channel, dma_modulo_t srcModulo, dma_modulo_t destModulo)
	Sets the DMA modulo for the DMA transfer. More...

static void	DMA_EnableCycleSteal (DMA_Type *base, uint32_t channel, bool enable)
	Enables the DMA cycle steal for the DMA transfer. More...

static void	DMA_EnableAutoAlign (DMA_Type *base, uint32_t channel, bool enable)
	Enables the DMA auto align for the DMA transfer. More...

static void	DMA_EnableAsyncRequest (DMA_Type *base, uint32_t channel, bool enable)
	Enables the DMA async request for the DMA transfer. More...

static void	DMA_EnableInterrupts (DMA_Type *base, uint32_t channel)
	Enables an interrupt for the DMA transfer. More...

static void	DMA_DisableInterrupts (DMA_Type *base, uint32_t channel)
	Disables an interrupt for the DMA transfer. More...

DMA Channel Transfer Operation
static void	DMA_EnableChannelRequest (DMA_Type *base, uint32_t channel)
	Enables the DMA hardware channel request. More...

static void	DMA_DisableChannelRequest (DMA_Type *base, uint32_t channel)
	Disables the DMA hardware channel request. More...

static void	DMA_TriggerChannelStart (DMA_Type *base, uint32_t channel)
	Starts the DMA transfer with a software trigger. More...

DMA Channel Status Operation
static uint32_t	DMA_GetRemainingBytes (DMA_Type *base, uint32_t channel)
	Gets the remaining bytes of the current DMA transfer. More...

static uint32_t	DMA_GetChannelStatusFlags (DMA_Type *base, uint32_t channel)
	Gets the DMA channel status flags. More...

static void	DMA_ClearChannelStatusFlags (DMA_Type *base, uint32_t channel, uint32_t mask)
	Clears the DMA channel status flags. More...

DMA Channel Transactional Operation
void	DMA_CreateHandle (dma_handle_t handle, DMA_Type base, uint32_t channel)
	Creates the DMA handle. More...

void	DMA_SetCallback (dma_handle_t handle, dma_callback callback, void userData)
	Sets the DMA callback function. More...

void	DMA_PrepareTransfer (dma_transfer_config_t config, void srcAddr, uint32_t srcWidth, void *destAddr, uint32_t destWidth, uint32_t transferBytes, dma_transfer_type_t type)
	Prepares the DMA transfer configuration structure. More...

status_t	DMA_SubmitTransfer (dma_handle_t handle, const dma_transfer_config_t config, uint32_t options)
	Submits the DMA transfer request. More...

static void	DMA_StartTransfer (dma_handle_t *handle)
	DMA starts a transfer. More...

static void	DMA_StopTransfer (dma_handle_t *handle)
	DMA stops a transfer. More...

void	DMA_AbortTransfer (dma_handle_t *handle)
	DMA aborts a transfer. More...

void	DMA_HandleIRQ (dma_handle_t *handle)
	DMA IRQ handler for current transfer complete. More...

Data Structure Documentation

struct dma_transfer_config_t

Data Fields
uint32_t	srcAddr
	DMA transfer source address. More...

uint32_t	destAddr
	DMA destination address. More...

bool	enableSrcIncrement
	Source address increase after each transfer. More...

dma_transfer_size_t	srcSize
	Source transfer size unit. More...

bool	enableDestIncrement
	Destination address increase after each transfer. More...

dma_transfer_size_t	destSize
	Destination transfer unit. More...

uint32_t	transferSize
	The number of bytes to be transferred. More...

Field Documentation

uint32_t dma_transfer_config_t::srcAddr

uint32_t dma_transfer_config_t::destAddr

bool dma_transfer_config_t::enableSrcIncrement

dma_transfer_size_t dma_transfer_config_t::srcSize

bool dma_transfer_config_t::enableDestIncrement

dma_transfer_size_t dma_transfer_config_t::destSize

uint32_t dma_transfer_config_t::transferSize

struct dma_channel_link_config_t

Data Fields
dma_channel_link_type_t	linkType
	Channel link type. More...

uint32_t	channel1
	The index of channel 1. More...

uint32_t	channel2
	The index of channel 2. More...

Field Documentation

dma_channel_link_type_t dma_channel_link_config_t::linkType

uint32_t dma_channel_link_config_t::channel1

uint32_t dma_channel_link_config_t::channel2

struct dma_handle_t

Data Fields
DMA_Type *	base
	DMA peripheral address. More...

uint8_t	channel
	DMA channel used. More...

dma_callback	callback
	DMA callback function. More...

void *	userData
	Callback parameter. More...

Field Documentation

DMA_Type* dma_handle_t::base

uint8_t dma_handle_t::channel

dma_callback dma_handle_t::callback

void* dma_handle_t::userData

Macro Definition Documentation

#define FSL_DMA_DRIVER_VERSION (MAKE_VERSION(2, 0, 1))

Typedef Documentation

typedef void(* dma_callback)(struct _dma_handle *handle, void *userData)

Enumeration Type Documentation

enum _dma_channel_status_flags

Enumerator
kDMA_TransactionsBCRFlag	Contains the number of bytes yet to be transferred for a given block.
kDMA_TransactionsDoneFlag	Transactions Done.
kDMA_TransactionsBusyFlag	Transactions Busy.
kDMA_TransactionsRequestFlag	Transactions Request.
kDMA_BusErrorOnDestinationFlag	Bus Error on Destination.
kDMA_BusErrorOnSourceFlag	Bus Error on Source.
kDMA_ConfigurationErrorFlag	Configuration Error.

enum dma_transfer_size_t

Enumerator
kDMA_Transfersize32bits	32 bits are transferred for every read/write
kDMA_Transfersize8bits	8 bits are transferred for every read/write
kDMA_Transfersize16bits	16b its are transferred for every read/write

enum dma_modulo_t

Enumerator
kDMA_ModuloDisable	Buffer disabled.
kDMA_Modulo16Bytes	Circular buffer size is 16 bytes.
kDMA_Modulo32Bytes	Circular buffer size is 32 bytes.
kDMA_Modulo64Bytes	Circular buffer size is 64 bytes.
kDMA_Modulo128Bytes	Circular buffer size is 128 bytes.
kDMA_Modulo256Bytes	Circular buffer size is 256 bytes.
kDMA_Modulo512Bytes	Circular buffer size is 512 bytes.
kDMA_Modulo1KBytes	Circular buffer size is 1 KB.
kDMA_Modulo2KBytes	Circular buffer size is 2 KB.
kDMA_Modulo4KBytes	Circular buffer size is 4 KB.
kDMA_Modulo8KBytes	Circular buffer size is 8 KB.
kDMA_Modulo16KBytes	Circular buffer size is 16 KB.
kDMA_Modulo32KBytes	Circular buffer size is 32 KB.
kDMA_Modulo64KBytes	Circular buffer size is 64 KB.
kDMA_Modulo128KBytes	Circular buffer size is 128 KB.
kDMA_Modulo256KBytes	Circular buffer size is 256 KB.

enum dma_channel_link_type_t

Enumerator
kDMA_ChannelLinkDisable	No channel link.
kDMA_ChannelLinkChannel1AndChannel2	Perform a link to channel LCH1 after each cycle-steal transfer. followed by a link to LCH2 after the BCR decrements to 0.
kDMA_ChannelLinkChannel1	Perform a link to LCH1 after each cycle-steal transfer.
kDMA_ChannelLinkChannel1AfterBCR0	Perform a link to LCH1 after the BCR decrements.

enum dma_transfer_type_t

Enumerator
kDMA_MemoryToMemory	Memory to Memory transfer.
kDMA_PeripheralToMemory	Peripheral to Memory transfer.
kDMA_MemoryToPeripheral	Memory to Peripheral transfer.

enum dma_transfer_options_t

Enumerator
kDMA_NoOptions	Transfer without options.
kDMA_EnableInterrupt	Enable interrupt while transfer complete.

Function Documentation

void DMA_Init ( DMA_Type * base )

This function ungates the DMA clock.

Parameters

base	DMA peripheral base address.

void DMA_Deinit ( DMA_Type * base )

This function gates the DMA clock.

Parameters

base	DMA peripheral base address.

void DMA_ResetChannel	(	DMA_Type *	base,
		uint32_t	channel
	)

Sets all register values to reset values and enables the cycle steal and auto stop channel request features.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

void DMA_SetTransferConfig	(	DMA_Type *	base,
		uint32_t	channel,
		const dma_transfer_config_t *	config
	)

This function configures the transfer attribute including the source address, destination address, transfer size, and so on. This example shows how to set up the the dma_transfer_config_t parameters and how to call the DMA_ConfigBasicTransfer function.

*   dma_transfer_config_t transferConfig;
*   memset(&transferConfig, 0, sizeof(transferConfig));
*   transferConfig.srcAddr = (uint32_t)srcAddr;
*   transferConfig.destAddr = (uint32_t)destAddr;
*   transferConfig.enbaleSrcIncrement = true;
*   transferConfig.enableDestIncrement = true;
*   transferConfig.srcSize = kDMA_Transfersize32bits;
*   transferConfig.destSize = kDMA_Transfersize32bits;
*   transferConfig.transferSize = sizeof(uint32_t) * BUFF_LENGTH;
*   DMA_SetTransferConfig(DMA0, 0, &transferConfig);
* 

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
config	Pointer to the DMA transfer configuration structure.

void DMA_SetChannelLinkConfig	(	DMA_Type *	base,
		uint32_t	channel,
		const dma_channel_link_config_t *	config
	)

This function allows DMA channels to have their transfers linked. The current DMA channel triggers a DMA request to the linked channels (LCH1 or LCH2) depending on the channel link type. Perform a link to channel LCH1 after each cycle-steal transfer followed by a link to LCH2 after the BCR decrements to 0 if the type is kDMA_ChannelLinkChannel1AndChannel2. Perform a link to LCH1 after each cycle-steal transfer if the type is kDMA_ChannelLinkChannel1. Perform a link to LCH1 after the BCR decrements to 0 if the type is kDMA_ChannelLinkChannel1AfterBCR0.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
config	Pointer to the channel link configuration structure.

static void DMA_SetSourceAddress	(	DMA_Type *	base,
		uint32_t	channel,
		uint32_t	srcAddr
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
srcAddr	DMA source address.

static void DMA_SetDestinationAddress	(	DMA_Type *	base,
		uint32_t	channel,
		uint32_t	destAddr
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
destAddr	DMA destination address.

static void DMA_SetTransferSize	(	DMA_Type *	base,
		uint32_t	channel,
		uint32_t	size
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
size	The number of bytes to be transferred.

void DMA_SetModulo	(	DMA_Type *	base,
		uint32_t	channel,
		dma_modulo_t	srcModulo,
		dma_modulo_t	destModulo
	)

This function defines a specific address range specified to be the value after (SAR + SSIZE)/(DAR + DSIZE) calculation is performed or the original register value. It provides the ability to implement a circular data queue easily.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
srcModulo	source address modulo.
destModulo	destination address modulo.

static void DMA_EnableCycleSteal	(	DMA_Type *	base,
		uint32_t	channel,
		bool	enable
	)

inlinestatic

If the cycle steal feature is enabled (true), the DMA controller forces a single read/write transfer per request, or it continuously makes read/write transfers until the BCR decrements to 0.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
enable	The command for enable (true) or disable (false).

static void DMA_EnableAutoAlign	(	DMA_Type *	base,
		uint32_t	channel,
		bool	enable
	)

inlinestatic

If the auto align feature is enabled (true), the appropriate address register increments regardless of DINC or SINC.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
enable	The command for enable (true) or disable (false).

static void DMA_EnableAsyncRequest	(	DMA_Type *	base,
		uint32_t	channel,
		bool	enable
	)

inlinestatic

If the async request feature is enabled (true), the DMA supports asynchronous DREQs while the MCU is in stop mode.

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
enable	The command for enable (true) or disable (false).

static void DMA_EnableInterrupts	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

static void DMA_DisableInterrupts	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

static void DMA_EnableChannelRequest	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	The DMA channel number.

static void DMA_DisableChannelRequest	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

static void DMA_TriggerChannelStart	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

This function starts only one read/write iteration.

Parameters

base	DMA peripheral base address.
channel	The DMA channel number.

static uint32_t DMA_GetRemainingBytes	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

Returns: The number of bytes which have not been transferred yet.

static uint32_t DMA_GetChannelStatusFlags	(	DMA_Type *	base,
		uint32_t	channel
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.

Returns: The mask of the channel status. Use the _dma_channel_status_flags type to decode the return 32 bit variables.

static void DMA_ClearChannelStatusFlags	(	DMA_Type *	base,
		uint32_t	channel,
		uint32_t	mask
	)

inlinestatic

Parameters

base	DMA peripheral base address.
channel	DMA channel number.
mask	The mask of the channel status to be cleared. Use the defined _dma_channel_status_flags type.

void DMA_CreateHandle	(	dma_handle_t *	handle,
		DMA_Type *	base,
		uint32_t	channel
	)

This function is called first if using the transactional API for the DMA. This function initializes the internal state of the DMA handle.

Parameters

handle	DMA handle pointer. The DMA handle stores callback function and parameters.
base	DMA peripheral base address.
channel	DMA channel number.

void DMA_SetCallback	(	dma_handle_t *	handle,
		dma_callback	callback,
		void *	userData
	)

This callback is called in the DMA IRQ handler. Use the callback to do something after the current transfer complete.

Parameters

handle	DMA handle pointer.
callback	DMA callback function pointer.
userData	Parameter for callback function. If it is not needed, just set to NULL.

void DMA_PrepareTransfer	(	dma_transfer_config_t *	config,
		void *	srcAddr,
		uint32_t	srcWidth,
		void *	destAddr,
		uint32_t	destWidth,
		uint32_t	transferBytes,
		dma_transfer_type_t	type
	)

This function prepares the transfer configuration structure according to the user input.

Parameters

config	Pointer to the user configuration structure of type dma_transfer_config_t.
srcAddr	DMA transfer source address.
srcWidth	DMA transfer source address width (byte).
destAddr	DMA transfer destination address.
destWidth	DMA transfer destination address width (byte).
transferBytes	DMA transfer bytes to be transferred.
type	DMA transfer type.

status_t DMA_SubmitTransfer	(	dma_handle_t *	handle,
		const dma_transfer_config_t *	config,
		uint32_t	options
	)

This function submits the DMA transfer request according to the transfer configuration structure.

Parameters

handle	DMA handle pointer.
config	Pointer to DMA transfer configuration structure.
options	Additional configurations for transfer. Use the defined dma_transfer_options_t type.

Return values

kStatus_DMA_Success	It indicates that the DMA submit transfer request succeeded.
kStatus_DMA_Busy	It indicates that the DMA is busy. Submit transfer request is not allowed.

Note: This function can't process multi transfer request.

static void DMA_StartTransfer ( dma_handle_t * handle )

inlinestatic

This function enables the channel request. Call this function after submitting a transfer request.

Parameters

handle DMA handle pointer.

Return values

kStatus_DMA_Success	It indicates that the DMA start transfer succeed.
kStatus_DMA_Busy	It indicates that the DMA has started a transfer.

static void DMA_StopTransfer ( dma_handle_t * handle )

inlinestatic

This function disables the channel request to stop a DMA transfer. The transfer can be resumed by calling the DMA_StartTransfer.

Parameters

handle DMA handle pointer.

void DMA_AbortTransfer ( dma_handle_t * handle )

This function disables the channel request and clears all status bits. Submit another transfer after calling this API.

Parameters

handle DMA handle pointer.

void DMA_HandleIRQ ( dma_handle_t * handle )

This function clears the channel interrupt flag and calls the callback function if it is not NULL.

Parameters

handle DMA handle pointer.

Overview

Typical use case

DMA Operation

Data Structures

Typedefs

Enumerations

Driver version

DMA Initialization and De-initialization

DMA Channel Operation

DMA Channel Transfer Operation

DMA Channel Status Operation

DMA Channel Transactional Operation

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation