下面是blcommon.c中的BootloaderMain代码
void BootloaderMain (void)
{
DWORD dwAction;
DWORD dwpToc = 0;
DWORD dwImageStart = 0, dwImageLength = 0, dwLaunchAddr = 0;
BOOL bDownloaded = FALSE;
// relocate globals to RAM
if (!KernelRelocate (pTOC))
{
// spin forever
HALT (BLERR_KERNELRELOCATE);
}
// (1) Init debug support. We can use OEMWriteDebugString afterward.
if (!OEMDebugInit ())
{
// spin forever
HALT (BLERR_DBGINIT);
}
// output banner
EdbgOutputDebugString (NKSignon, CURRENT_VERSION_MAJOR, CURRENT_VERSION_MINOR);
// (3) initialize platform (clock, drivers, transports, etc)
if (!OEMPlatformInit ())
{
// spin forever
HALT (BLERR_PLATINIT);
}
// system ready, preparing for download
EdbgOutputDebugString ("System ready!\r\nPreparing for download...\r\n");
// (4) call OEM specific pre-download function
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 bms
}
// 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);
}
}
现在程序已经执行通过了DownloadImage函数，运行到了OEMMapMemAddr函数以后 就进入了该函数里面了。并且运行到 EdbgOutputDebugString ("ROMHDR at Address %Xh\r\n", dwImageStart + ROM_SIGNATURE_OFFSET + sizeof (DWORD));的时候就在超级终端显示了ROMHDR at Address 80201044h 就不动了，能给出进一步的解释吗？谢谢了
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