cacheCoherentMemoryProvider.h File Reference

Provides a way to easily allocate memory areas that are coherent between CPU and DMA. More...

#include <stdint.h>
#include <stddef.h>

Go to the source code of this file.

Data Structures
struct	ccmb_desc_struct
	Describes a Cache Coherent Memory Block allocated by ccmp_malloc() More...

Typedefs
typedef struct ccmb_desc_struct	Ccmb_desc
	Describes a Cache Coherent Memory Block allocated by ccmp_malloc()

Functions
int	ccmp_malloc (size_t reqSize, Ccmb_desc *allocatedAreaDesc, unsigned int byteAlignment)
	Provides a way to easily allocate memory areas that are coherent between CPU and DMA. More...
int	ccmp_free (Ccmb_desc *allocatedAreaDesc)
	Frees a block allocated with ccmp_malloc() More...
uintptr_t	ccmp_virtAddrToBusAddr (Ccmb_desc *desc, void *virtAddr)
	Converts a virtual address inside the block described by desc to it's bus address. More...

Detailed Description

Provides a way to easily allocate memory areas that are coherent between CPU and DMA.

This files provides functions to get blocks of memory with known associated physical address that are cache coherent. This is useful when interfacing with peripherals that access memory directly, bypassing the L1 or L2 caches, like the DMA.

Function Documentation

int ccmp_free

(

Ccmb_desc *

allocatedAreaDesc

)

Frees a block allocated with ccmp_malloc()

Returns

negative in case of error

int ccmp_malloc	(	size_t	reqSize,
		Ccmb_desc *	allocatedAreaDesc,
		unsigned int	byteAlignment
	)

Provides a way to easily allocate memory areas that are coherent between CPU and DMA.

Parameters

reqSize	The size of the block to be allocated.
allocatedAreaDesc	Here will be returned the descriptor for the allocated block
byteAlignment	The allocated block will be aligned to this value

Returns

negative in case of error

uintptr_t ccmp_virtAddrToBusAddr	(	Ccmb_desc *	desc,
		void *	virtAddr
	)

Converts a virtual address inside the block described by desc to it's bus address.

Returns

the bus address