lp_dma_dsp_b.c

老外写的TS201 LinkPort DMA发送/接收程序

//  Link port DMA in C using builtin functions

#include "sysreg.h"
#include "signal.h"
#include "stdio.h"
#include <defts201.h>

#define N 64										// Number of words to transfer

float dm buffer[N];									// Buffer for received data and for transmitting back

struct TCB {
	float *DI;										// index
	int DX;											// count and stride in x direction
	int DY;											// count and stride in y direction
	int DP;											// DMA control word
};

struct TCB TCB_temp;								// Temp structure for programming TCBs

__builtin_quad q;									// Temp quad for programming TCBs

void isr_DMA6(int);									// Protos for isr's
void isr_DMA10(int);

void main(void)
{
	int i;
	volatile int k;											// loop var
	

	interrupt(SIGDMA6, isr_DMA6);					// Assign isr to DMA channel 6
	interrupt(SIGDMA10, isr_DMA10);					// Assign isr to DMA channel 10

	TCB_temp.DI = buffer;							// index points to destination buffer
	TCB_temp.DX = 4 | (N << 16);					// modify is 4 for quad-word transfers, count is N and must be shifted to upper half 
	TCB_temp.DY = 0;								// only a 1 dimension DMA
	TCB_temp.DP = 0x47000000;						// control word set for quad-word transfers to internal memory with interrupt enabled

	__builtin_sysreg_write(__LTCTL2,0x1);			// setup LP2 to transmit
	__builtin_sysreg_write(__LRCTL2,0x1);			// and also setup LP2 to receive
	
//******************************************************************************
/* Following lines of code insert a wait time of (75000 * LxCLKO_period) between
   link transmit port and due to
   a silicon anomaly on ADSP-TS201. Please refer TigerSHARC anomaly list (revisions
   1.0 and 1.1) for more details */
//******************************************************************************

for (i=0;i<75000;i++) 
		k=i+1;		

	
	q = __builtin_compose_128((long long)TCB_temp.DI | (long long)TCB_temp.DX << 32, (long long)(TCB_temp.DY | (long long)TCB_temp.DP << 32));
	__builtin_sysreg_write4(__DC10, q);				// program the TCBs

	while(1)										// Endless loop
		i=i-i;
}

void isr_DMA10(int dummy)							// isr for DMA channel 10, sets up DMA channel 6 to transmit buffer back
{		
	TCB_temp.DI = buffer;							// index points to buffer
	TCB_temp.DP = 0x47000000;						// control word set for quad-word transfers to internal memory with interrupt enabled

	q = __builtin_compose_128((long long)TCB_temp.DI | (long long)TCB_temp.DX << 32, (long long)(TCB_temp.DY | (long long)TCB_temp.DP << 32));
	__builtin_sysreg_write4(__DC6, q);				// program the TCBs

	return;
}

void isr_DMA6(int dummy)							// isr for DMA channel 6
{		
	printf("LP DMAs Complete\n");

	return;
}