loader.c

s3c2440bootloader的stepldr修改版

#include <stdlib.h>
#include <string.h>
#include "option.h"
#include "s2440addr.h"
#include "def.h"
#include "utils.h"
#include "nand.h"

// Constants.

// #define NAND_BLOCK_SIZE_BYTES   0x00020000
#define NAND_BLOCK_SIZE_BYTES   0x00004000       // 16K/Page
#define NAND_PAGE_SIZE_BYTES    0x00000200       // 512Bytes/Page
#define NAND_PAGES_PER_BLOCK    (NAND_BLOCK_SIZE_BYTES / NAND_PAGE_SIZE_BYTES)

    // NOTE: we assume that this Steppingstone loader occupies *part* the first (good) NAND flash block.  More
    // specifically, the loader takes up 4096 bytes (or 8 NAND pages) of the first block.  We'll start our image
    // copy on the very next page.
#define NAND_COPY_PAGE_OFFSET   2*NAND_PAGES_PER_BLOCK

#define LOAD_ADDRESS_PHYSICAL   0x30038000
#define LOAD_SIZE_BYTES         0x00040000
#define LOAD_SIZE_PAGES         (LOAD_SIZE_BYTES / NAND_PAGE_SIZE_BYTES)

typedef void (*PFN_IMAGE_LAUNCH)();

/*
    @func   void | main | C entrypoint function for the Steppingstone loader.
    @rdesc  None.
    @comm    
    @xref   
*/
void Main(void)
{
    register nBlock;
    register nPage;
    register nBadBlocks;
    volatile BYTE *pCopyPtr;
    
    // Enable the ICache.
    MMU_EnableICache();
    
    // Set up all GPIO ports.
    Port_Init();

    // Initialize UART for debug
	Uart_Init();
    
	Uart_SendString("Loading......\r\n");

    // Initialize the NAND flash interface.
    NF_Init();

    // Copy image from NAND flash to RAM.
    pCopyPtr = (BYTE *)LOAD_ADDRESS_PHYSICAL;

    // NOTE: we assume that this Steppingstone loader occupies *part* the first (good) NAND flash block.  More
    // specifically, the loader takes up 4096 bytes (or 8 NAND pages) of the first block.  We'll start our image
    // copy on the very next page.

	FlashID = NF_ReadID();

	if (!FlashID)
	{
		Uart_SendString("This NandFlash Type is not supported!!\r\n Booting is failure \r\n");
		while(1)
		{
			;
		}
	}
    
    nBadBlocks = 0;
    for (nPage = NAND_COPY_PAGE_OFFSET ; nPage < (LOAD_SIZE_PAGES + NAND_COPY_PAGE_OFFSET) ; nPage++)
    {
        nBlock = ((nPage / NAND_PAGES_PER_BLOCK) + nBadBlocks);

        if (!NF_ReadPage(nBlock, (nPage % NAND_PAGES_PER_BLOCK), pCopyPtr))
        {
            if ((nPage % NAND_PAGES_PER_BLOCK) != 0)
            {
                // Spin forever...
                while(1)
                {
                    ;
                }
            }

            // ECC error on a block boundary is (likely) a bad block - retry the page 0 read on the next block.
            nBadBlocks++;
            nPage--;
            continue;
        }
        
	    Uart_SendString("*");

        pCopyPtr += NAND_PAGE_SIZE_BYTES;
    }

    Uart_SendString("\r\nRunning......\r\n");
	
    // Jump to the image...
    ((PFN_IMAGE_LAUNCH)(LOAD_ADDRESS_PHYSICAL))();
}