[ARM 디바이스 제어_Day3]DMA

■DMA Interrupt■

 
#if EXAMPLE == 360
void MemFill(unsigned long ptr, unsigned long pattern, int size)
{
    int i;
    unsigned long *data;
    data = (unsigned long *)ptr;
 
    for (i=0; i<size;i++)
        *data++ = pattern;
}
 
void MemDump(unsigned long ptr, int size)
{
    int i;
    unsigned long *data;
    data = (unsigned long *)ptr;
 
    Uart_Printf("\n");
    Uart_Printf("*** Dump Memory from [0x%08x] to [0x%08x] : \n",ptr, (unsigned long *)ptr+size);
    for (i=0; i<size;i++) {
        if ( !(i%4) )
            Uart_Printf("\n  [0x%08x] : ",data);
        Uart_Printf("0x%08x ",*data++);
    }
    Uart_Printf("\n");
}
 
 
 
 
#define pISR_DMA0        (*(unsigned *)(0x33ffff64))
static unsigned long src = 0x33000000;
static unsigned long dst = 0x33100000;
static unsigned int size = 12; //word size
unsigned long pattern;
 
static void DMA0_interrupt()
{
    
    rINTSUBMSK |=(0<<18);
    rINTMSK1 |=(1<<17);
    
    rSUBSRCPND |= 0x1<<18;
    rSRCPND1|=(1<<17);    //clear
    rINTPND1 |=(1<<17);    //clear
 
    Uart_Send_String("\n###DMA START ...!!");
    MemDump(dst,size);
 
    rDMASKTRIG0 |= 0x1 <<2;
 
    rINTSUBMSK &=~(1<<18);
    rINTMSK1 &=~(1<<17);
 
}
 
void Main(void)
{    
    rDMASKTRIG0=0x0;
 
    //src , dest init
    rDISRC0 = src;
    rDIDST0 = dst;
 
    //disrcc , didstc init
    rDISRCC0 &= ~0x3;
    rDIDSTC0 &= ~0x7;
 
    //dcon    init 
    rDCON0 = (1<<31) | (1<<30) | (1<<29) |(0<<28) | (1<<27)| (1<<24) | (0<<23)|(0<<22) | (0<<20)|(size*4<<0);
 
    
    //S/W request mode;0
    rDMAREQSEL0= (0x0<<0);    
 
    
    MemFill(src,0x00000000,size);
    MemFill(dst,0x00000000,size);
 
    pattern = 0x5555aaaa;
 
    MemFill(src,pattern,size);    //src malloc;
    MemDump(src,size);
 
 
    //on_off mode ; sw trigger(start)
    rDMASKTRIG0 = (1<<1) | (1<<0);
 
 
    //interrupt handler set
    pISR_DMA0= (unsigned int)DMA0_interrupt;
 
 
    rINTSUBMSK &=~(0<<18);
    rINTMSK1 &=~(1<<17);
 
}
# endif 

1.시작지점과 목적지점의 주소를 입력

 rDISRC0 = src;

 rDIDST0 = dst; 

 rDISRCC0 &= ~0x3; 

 rDIDSTC0 &= ~0x7;

2. DCON0 설정

/*setting for S/W DMA request

DCON0 : Handshake[31-1], HCLK[30-1], INT mode[29-1], Single Unit[28-0], Whole service[27-1],

HW_select[26:24],  S/W trigger[23-0], Auto Reload ON[22-0], Byte size[21:20](Note: Word size<->Byte size)*/

3. 소프트웨어 인터럽트로 설정

rDMAREQSEL0 = (0x0<<0);

4. 트리거 설정, start    =>소프트웨어 인터럽트

rDMASKTRIG0 = (1<<1) | (1<<0);

5.

rINTSUBMSK    DMA모드로 설정

rINTMSK1 &=~(1<<17);    interrupt 허용