memdma_move1d.asm

blackfin开发板 BF533-sdram_memdma开发代码 包括sdram读写

#include "defBF533.h"

#define SRCMEM1DCFG	0x6809  // DMA read
#define DSTMEM1DCFG	0x680B  // DMA write


.extern MemDMAQueue;

.section L1_data_a;
.align 4;



Next_Descriptor_Address:
.byte4 _Next_Descriptor_Address[2] = 	MemDMAQueue, 
										MemDMAQueue;

.section L1_code;
.align 4;

.global memdma_move1D; 
memdma_move1D:
	p1.l = Next_Descriptor_Address;
	p1.h = Next_Descriptor_Address;
	r5 = [p1++];
	i0 = r5;
	r4 = [p1--];
	b0 = r4;
	l0 = 32;
	m0 = 8;
	nop;
/*****************************************************************************************
	dummy read skip the SOURCE_NEXT_DESC_ADDRESS
******************************************************************************************/	
	r4.l = w[i0++];
/******************************************************************************************
	set start address
******************************************************************************************/	
	w[i0++] = r0.l;
	w[i0++] = r0.h;
/******************************************************************************************
	set DMA_CONFIG
******************************************************************************************/	
	r0.l = SRCMEM1DCFG;
	w[i0++] = r0.l;
/******************************************************************************************
	set XCNT/XMODIFY
******************************************************************************************/	
	[i0++m0] = r1;
	
	r4.l = w[i0++];				
	w[i0++] = r3.l;			
	w[i0++] = r3.h;				
	r3.l = DSTMEM1DCFG;
	w[i0++] = r3.l;				
	[i0++m0] = r1;
	
	l0 = 0;
	r0 = i0;
	[p1] = r0;					//update tail with NDP value
	r0 = r5;		

	rts;
memdma_move1D.end: