DMA transfer length problem

Try to use io.h's functions IOWR and IORD as next:

unsigned int *p = (unsigned int*)(SDRAM_BASE + 0xF4240);

void *pdma = (void*) SD_DMA_BASE;

//Interrupt function if need

void isr_dma(void* context, alt_u32 id)

{

if ((IORD_ALTERA_AVALON_DMA_STATUS(SD_DMA_BASE))&&ALTERA_AVALON_DMA_STATUS_DONE_MSK) {

IOWR_ALTERA_AVALON_DMA_STATUS(SD_DMA_BASE, 0);

IOWR_ALTERA_AVALON_DMA_RADDRESS(SD_DMA_BASE, (int)p);

IOWR_ALTERA_AVALON_DMA_WADDRESS(SD_DMA_BASE, SD_BASE);

IOWR_ALTERA_AVALON_DMA_LENGTH(SD_DMA_BASE, 40);

IOWR_ALTERA_AVALON_DMA_CONTROL(SD_DMA_BASE, 0x02DC);

}

}

int main(void)

{

unsigned int *p = (unsigned int*)(SDRAM_BASE + 0xF4240);

.............

//Write to memory something (in this case 10 words)

for (i=0, pattern=0xFFAAFFAA; i<10; i++)

{

IOWR_32DIRECT(p+i, 0, pattern);

}

//Registration of interrupt function if it need

alt_irq_register(SD_DMA_IRQ, pdma, isr_dma);

//Send to some device 10 words

IOWR_ALTERA_AVALON_DMA_STATUS(SD_DMA_BASE, 0);

IOWR_ALTERA_AVALON_DMA_RADDRESS(SD_DMA_BASE, (int)p); //Pointer to memory

IOWR_ALTERA_AVALON_DMA_WADDRESS(SD_DMA_BASE, SD_BASE); //Pointer to your device

IOWR_ALTERA_AVALON_DMA_LENGTH(SD_DMA_BASE, 40); //Sending 10 words (1 word == 4 bytes)

IOWR_ALTERA_AVALON_DMA_CONTROL(SD_DMA_BASE, 0x02DC); //See description of dma control register

...............

}