M2M DMA (Memory-to-Memory Direct Memory Access)

General Description

M2M DMA allows transferring data between memory regions without CPU intervention.

It can be used to transfer WIFI data between the Apps processor and the WLAN processor through the WWD driver.

Macros
#define	ACPU_DMA_TX_CHANNEL   (1)
	Application CPU DMA TX channel.
#define	ACPU_DMA_RX_CHANNEL   (0)
	Application CPU DMA RX channel.
#define	WCPU_DMA_TX_CHANNEL   (0)
	WLAN CPU DMA TX channel.
#define	WCPU_DMA_RX_CHANNEL   (1)
	WLAN CPU DMA RX channel.
#define	MEMCPY_M2M_DMA_CHANNEL   (2)
	MEMCPY M2M DMA channel.
#define	MEMCPY_USR_DMA_CHANNEL   (3)
	User M2M DMA channel.
#define	USR1_DMA_TX_CHANNEL   (4)
	User DMA TX channel 1.
#define	USR1_DMA_RX_CHANNEL   (5)
	User DMA RX channel 1.
#define	USR2_DMA_TX_CHANNEL   (6)
	User DMA TX channel 2.
#define	USR2_DMA_RX_CHANNEL   (7)
	User DMA RX channel 2.
#define	_CYHAL_M2M_GRPS   (3)
	Number of available channel groups.
#define	SDPCMD_RXOFFSET   (8)
	RX offset.

Enumerations
enum	_cyhal_m2m_group_t {   _CYHAL_M2M_GRP_WWD ,   _CYHAL_M2M_GRP_USR_1 ,   _CYHAL_M2M_GRP_USR_2 }
	M2M DMA group. More...

Functions
void	_cyhal_m2m_init_dma (_cyhal_m2m_group_t group, uint8_t tx_ch, uint8_t rx_ch, uint32_t rx_buffer_size)
	Common M2M initialization routine. More...
void	_cyhal_m2m_disable_dma (uint8_t dma_ch)
	Common M2M disable DMA routine. More...
void	_cyhal_m2m_deinit_dma (_cyhal_m2m_group_t group)
	Common M2M deinitialization routine. More...
bool	_cyhal_m2m_tx_is_idle (_cyhal_m2m_group_t group)
	Common M2M routine to check if communication is idle. More...
void	_cyhal_m2m_get_channels (_cyhal_m2m_group_t group, uint8_t *tx_ch, uint8_t *rx_ch, uint8_t *dma_ch)
	Common M2M routine to get the channels for a given group. More...
void	_cyhal_m2m_unprotected_dma_memcpy (uint8_t dma_ch, void *destination, const void *source, uint32_t byte_count)
	Common M2M function for initiating a regular DMA transfer. More...

Enumeration Type Documentation

_cyhal_m2m_group_t

enum _cyhal_m2m_group_t

M2M DMA group.

Enumerator
_CYHAL_M2M_GRP_WWD	Group used for WWD.
_CYHAL_M2M_GRP_USR_1	User group 1.
_CYHAL_M2M_GRP_USR_2	User group 2.

Function Documentation

_cyhal_m2m_init_dma()

void _cyhal_m2m_init_dma	(	_cyhal_m2m_group_t	group,
		uint8_t	tx_ch,
		uint8_t	rx_ch,
		uint32_t	rx_buffer_size
	)

Common M2M initialization routine.

Function for initializing a DMA group consisting of TX, RX, and DMA channels.

Parameters

[in]	group	Group number
[in]	tx_ch	TX channel number
[in]	rx_ch	RX channel number
[in]	rx_buffer_size	RX buffer size

_cyhal_m2m_disable_dma()

void _cyhal_m2m_disable_dma

(

uint8_t

dma_ch

)

Common M2M disable DMA routine.

Function for disabling a DMA channel

Parameters

[in]

dma_ch

DMA channel number

_cyhal_m2m_deinit_dma()

void _cyhal_m2m_deinit_dma

(

_cyhal_m2m_group_t

group

)

Common M2M deinitialization routine.

Function for deinitializing a DMA group.

Parameters

[in]

group

Group number

_cyhal_m2m_tx_is_idle()

bool _cyhal_m2m_tx_is_idle

(

_cyhal_m2m_group_t

group

)

Common M2M routine to check if communication is idle.

Parameters

[in]

group

Group number

Returns

Idle (true) or Busy (false)

_cyhal_m2m_get_channels()

void _cyhal_m2m_get_channels	(	_cyhal_m2m_group_t	group,
		uint8_t *	tx_ch,
		uint8_t *	rx_ch,
		uint8_t *	dma_ch
	)

Common M2M routine to get the channels for a given group.

Parameters

[in]	group	Group number
[in]	tx_ch	TX channel number
[in]	rx_ch	RX channel number
[in]	dma_ch	DMA channel number

_cyhal_m2m_unprotected_dma_memcpy()

void _cyhal_m2m_unprotected_dma_memcpy	(	uint8_t	dma_ch,
		void *	destination,
		const void *	source,
		uint32_t	byte_count
	)

Common M2M function for initiating a regular DMA transfer.

Parameters

[in]	dma_ch	DMA channel number
[in]	destination	Destination address
[in]	source	Source address
[in]	byte_count	Number of bytes to transfer