I have a DMA-problem perhaps related to this upgrade:
I copied an example from the Altera Nios II Software Developer’s Handbook, chapter "Using DMA Devices" using memory to memory data transfer. I modified the code a bit
The good tghing is that there are no error messages, but the dma-transfer does not finish by setting the rx_done flag.
Perhaps a beginners fault? Can somebody help me?
Freeck
# include <stdio.h># include "system.h"# include "sys/alt_dma.h"# include "alt_types.h"
/* Create the transmit channel */
static volatile int rx_done = 0;
static void done (void* handle, void* data)
{
rx_done++;
}
int main (int argc, char* argv[], char* envp[])
{
int rc;
alt_u8 Inbuf[1024], Outbuf[1024];
alt_dma_txchan txchan;
alt_dma_rxchan rxchan;
void* tx_data = (void*) &Inbuf[0]; /* pointer to data to send */
void* rx_buffer = (void*) &Outbuf[0]; /* pointer to rx buffer */
if ((txchan = alt_dma_txchan_open("/dev/dma_0")) == NULL)
{
printf ("Failed to open transmit channel\n");
exit (1);
}
/* Create the receive channel */
if ((rxchan = alt_dma_rxchan_open("/dev/dma_0")) == NULL)
{
printf ("Failed to open receive channel\n");
exit (1);
}
/* Post the transmit request */
if ((rc = alt_dma_txchan_send (txchan,tx_data,1024,NULL,NULL)) < 0)
{
printf ("Failed to post transmit request, reason = %i\n", rc);
exit (1);
}
/* Post the receive request */
if ((rc = alt_dma_rxchan_prepare (rxchan,rx_buffer,1024,done,NULL)) < 0)
{
printf ("Failed to post read request, reason = %i\n", rc);
exit (1);
}
/* wait for transfer to complete */
printf ("wait for transfer to complete\n");
while (!rx_done);
printf("Transfer successful!\n");
return 0;
}
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