21 lines
780 B
C
21 lines
780 B
C
#include <gint/dma.h>
|
|
|
|
/* Allocate a 32-byte buffer in ILRAM */
|
|
GALIGNED(32) GILRAM static uint32_t ILbuf[8];
|
|
|
|
/* dma_memset(): Fast 32-aligned memset */
|
|
void *dma_memset(void *dst, uint32_t l, size_t size)
|
|
{
|
|
/* Prepare the ILRAM buffer. We need to use ILRAM because the DMA will
|
|
have to read the operand once per block, as opposed to an assembler
|
|
routine that would hold it in a register. If we place it in RAM, the
|
|
DMA will perform twice as many RAM accesses as the handwritten
|
|
assembler, which would be very slow. By using ILRAM we use two
|
|
different memory regions, making the DMA faster than the CPU. */
|
|
for(int i = 0; i < 8; i++) ILbuf[i] = l;
|
|
|
|
dma_transfer(1, DMA_32B, size >> 5, ILbuf, DMA_FIXED, dst, DMA_INC);
|
|
dma_transfer_wait(1);
|
|
return dst;
|
|
}
|