s3c6410 DMA implementation (entry level)

 char dest[200] = "kkkk\n";

void dma_init(void)
{
 DMACConfiguration = 1; //Enable the overall DMA
 DMACC7SrcAddr = (int)src; //Assign the source address to the source address register
 DMACC7DestAddr = (int)dest; //Assign the destination address to the destination address register
 DMACC7Control0 = 0x0c000000; //Set [26] [27] to 1, so that the source address and destination address are incremented after sending
 DMACC7Control1 = 0x64; //Write the size of the copy;
 DMACC7Configuration |= 1<<0; //Open channel7 DMA 
}

main()

{

dma_init();
 delay();
 my_puts("----------------\n");
 my_puts(src);
 my_puts(dest);

}

The src and dest contents printed out later are the same

Programming steps for operating DMA in the 6410 manual:

Steps to program a DMA channel: 

1. Decide whether use secure DMAC(SDMAC) or general DMAC(DMAC). In order to use general DMAC,

disable secure DMA control register(SDMA_SEL) of system controller. (Reset value is SDMAC)

2. Select a free DMA channel with the priority needed. Where DMA channel 0 has the highest priority and DMA   

channel 7 the lowest priority.  

DMACCXCONFIGURATION

DMACC7Configuration [0] bit value 1

3. Clear any pending interrupts on the channel to be used by writing to the DMACIntTCClr and DMACIntErrClr

registers. The previous channel operation might have left interrupts active.

4. Write the source address into the DMACCxSrcAddr register.

5. Write the destination address into the DMACCxDestAddr register.

6. Write the address of the next LLI into the DMACCxLLI register. If the transfer comprises of a single packet of

data then must be written into this register.

Offset Contents

Next LLI address Source Address for next transfer

Next LLI address + 0x04 Destination Address for next transfer

Next LLI address + 0x08 Next LLI address for next transfer

Next LLI address + 0x0C DMACCxControl0 data for next transfer

Next LLI address + 0x10 DMACCxControl1 data for next transfer

7. Write the control information into the DMACCxControl register.

DMACCxControl0

DMACCxControl1         transfer size

8. Write the channel configuration information into the DMACCxConfiguration register. If the Enable bit is set

then the DMA channel is automatically enabled.