sdram

ADI公司Blackfin系列DSP BF533读取SDRAM数据

/* =============================================================================
 *
 *  Description: This is a C implementation for Thread BootThread
 *
 * -----------------------------------------------------------------------------
 *  Comments:
 *
 * ===========================================================================*/

/* Get access to any of the VDK features & datatypes used */
#include "BootThread.h"
#include <cdefBF532.h>

// Memory DMA source data is SDRAM
// fill this memory with some known data during start.
//
int dma_dst_data[256];

// Initialize SDRAM with default values 
// SCLK = 133MHz 
// Bank-0 Enabled size 32 MB
//
static void Init_SDRAM()
{
	// check if SDRAM is already configured.
	//
	if(!(*pEBIU_SDSTAT & 0x8)) return;
	
	*pEBIU_SDGCTL = 0x0091998D;
	*pEBIU_SDBCTL = 0x13;
	*pEBIU_SDRRC  = 0x1A0;	
	ssync();
}


static void Populate_SDRAM(unsigned int addr, int size)
{
	int i=0;
	unsigned int pattern = 0x1;
	volatile unsigned int *pAddr = (unsigned int volatile*)addr;
	
	for(i=0;i< size; i++)
	 *pAddr++ = pattern++;
}
void
BootThread_RunFunction(void **inPtr)
{
	int i;
	
	// Initialize SDRAM
	//
	Init_SDRAM();
	
	// Fill values with 0xDEADBEEF from 0x000000 up to 100 integer locations
	//
	Populate_SDRAM(0x00000000,10);
	
	// Initilize the destiation size 
	//
	memset(dma_dst_data,0,sizeof(int)*256);
	
	
	  printf("Before DMA transfer the values are:\n");
    for(i=0; i< 10; i++)
    	printf("%d   ",dma_dst_data[i]);
    printf("\n");
	
	// 
	// DMA source stream configuration. MDMA_S0_xxx
	// Setting up source start address, Count and Modify.
	// 
	// In the below example we were asking to transfer 10, 32 bit
	// values from the SDRAMs source location to the destination.
	//
	*pMDMA_S0_START_ADDR = 	0x0; // SDRAM start address
	*pMDMA_S0_X_COUNT    =  10;  // Number of elements to transfer
	*pMDMA_S0_X_MODIFY   =  4;	 // 4 byte increment (one int each time)
	*pMDMA_S0_Y_MODIFY   =  0;	 // 1D transfer so its 0
	*pMDMA_S0_Y_COUNT    =  0;	 // 1D transfer so its 0
	
	//
	// DMA destination configuration. It has to be same as the
	// Source stream exept the start address.
	// 
	*pMDMA_D0_START_ADDR = 	dma_dst_data;
	*pMDMA_D0_X_COUNT    =  10;	  // Number of elements to transfer
	*pMDMA_D0_X_MODIFY   =  4;   // 4 byte increment (one int each time)
	*pMDMA_D0_Y_MODIFY   =  0;	 // 1D transfer so its 0
	*pMDMA_D0_Y_COUNT    =  0;	 // 1D transfer so its 0
	
	// 
	// Configuring the Source Stream. Source stream configuration
	// register. Always configure the Source Stream first. As soon
	// as destination stream configure register's DMA bit is enabled
	// DMA transfer starts. By default the source stream is memory read.
	//
	*pMDMA_S0_CONFIG  = 1 << 0;  // Enable DMA
	*pMDMA_S0_CONFIG |= 1 << 3;  // Enable 32 bit DMA				   
	ssync();
	
	//
	// Configure the Destination Stream. Destination Stream has to be configureed
	// as memory write. Confiure to transfer 16 bit words.We want an interrupt
	// after DMA is completed. At the end Enable DMA. As soon as the bit 0 is enabled
	// in the Destination configure register DMA transfer starts.
	//
	*pMDMA_D0_CONFIG  = 1 << 7; // Enable interrupts
	*pMDMA_D0_CONFIG |= 1 << 3; // Enable 32 bit DMA
	*pMDMA_D0_CONFIG |= 1 << 1; // DMA Memory Write
	*pMDMA_D0_CONFIG |= 1 << 0; // Enable DMA
	
		
	idle();
	
	// Acknowledge the DMA interrupt. The status bit is set.
	//
	*pMDMA_D0_IRQ_STATUS = 0x1;
	
	// Signal the DMA thread to read the values and print
	//
	VDK_PostSemaphore(kdmaComplete);
	
}

int
BootThread_ErrorFunction(void **inPtr)
{

    /* TODO - Put this thread's error handling code HERE */

      /* The default ErrorHandler kills the thread */

	VDK_DestroyThread(VDK_GetThreadID(), false);
	return 0;
}

void
BootThread_InitFunction(void **inPtr, VDK_ThreadCreationBlock *pTCB)
{
    /* Put code to be executed when this thread has just been created HERE */

    /* This routine does NOT run in new thread's context.  Any non-static thread
     *   initialization should be performed at the beginning of "Run()."
     */
}

void
BootThread_DestroyFunction(void **inPtr)
{
    /* Put code to be executed when this thread is destroyed HERE */

    /* This routine does NOT run in the thread's context.  Any VDK API calls
     *   should be performed at the end of "Run()."
     */
}

/* ========================================================================== */