原创 S3C2450 Bootloader调试总结之三

    switch (dwAction =OEMPreDownload ())

    {

    case BL_DOWNLOAD:

        // (5) download image

        if (!DownloadImage (&dwImageStart, &dwImageLength, &dwLaunchAddr))

        {

            // error already reported in DownloadImage

            SPIN_FOREVER;

        }

        bDownloaded = TRUE;

        // Check for pTOC signature ("CECE") here, after image in place

        if (*(LPDWORD) OEMMapMemAddr (dwImageStart, dwImageStart + ROM_SIGNATURE_OFFSET) == ROM_SIGNATURE)

        {

            dwpToc = *(LPDWORD) OEMMapMemAddr (dwImageStart, dwImageStart + ROM_SIGNATURE_OFFSET + sizeof(ULONG));

            // need to map the content again since the pointer is going to be in a fixup address

            dwpToc = (DWORD) OEMMapMemAddr (dwImageStart, dwpToc + g_dwROMOffset);

            EdbgOutputDebugString ("ROMHDR at Address %Xh\r\n", dwImageStart + ROM_SIGNATURE_OFFSET + sizeof (DWORD)); // right after signature

        }

        // fall through

    case BL_JUMP:

        // Before jumping to the image, optionally check the image signature.

        // NOTE: if we haven't downloaded the image by now, we assume that it'll be loaded from local storage in OEMLaunch (or it

        // already resides in RAM from an earlier download), and in this case, the image start address might be 0.  This means

        // that the image signature routine will need to find the image in storage or in RAM to validate it.  Since the OEM"s

        // OEMLaunch function will need to do this anyways, we trust that it's within their abilities to do it here.

        //

        if (g_bBINDownload && g_pOEMCheckSignature)

        {

            if (!g_pOEMCheckSignature(dwImageStart, g_dwROMOffset, dwLaunchAddr, bDownloaded))

                HALT(BLERR_CAT_SIGNATURE);

        }

        // (5) final call to launch the image. never returned

        OEMLaunch (dwImageStart, dwImageLength, dwLaunchAddr, (const ROMHDR *)dwpToc);

        // should never return

        // fall through

    default:

        // ERROR! spin forever

        HALT (BLERR_INVALIDCMD);

    }

}