Allocates memory from specified segment for a "hardware buffer" (a buffer that can be accessed via a DMA engine). The returned buffer will be padded in function of memory segment's properties.
Files
lib_mem.h/lib_mem.c
Prototype
Arguments
p_name
Pointer to allocated object name. Used for allocations tracking. May be DEF_NULL.
p_seg
Pointer to segment from which to allocate memory.
size
Size of memory block to allocate, in bytes.
align
Required alignment of memory block, in bytes. MUST be a power of 2.
p_bytes_reqd
Pointer to variable that will receive the number of free bytes missing for the allocation to succeed. Set to DEF_NULL to skip calculation.
p_err
Pointer to variable that will receive the return error code from this function.
LIB_MEM_ERR_NONE
LIB_MEM_ERR_INVALID_MEM_SIZE
LIB_MEM_ERR_INVALID_MEM_ALIGN
LIB_MEM_ERR_NULL_PTR
LIB_MEM_ERR_SEG_OVF
Returned Value
Pointer to allocated memory block, if successful.
DEF_NULL, otherwise.
Required Configuration
None.
Notes / Warnings
- The buffer returned by this function will be padded according to the
padding_alignargument passed at creation of this memory segment. This is particularly useful with systems that use cache memory and DMA engine to copy buffers as it guarantees that nothing else will be allocated on the same cache line (as long as thepadding_alignargument is set to the length of a cache line). - For a usage example of this function, refer to Memory Segments page.