//*****************************************************************************
//
//! Checks if an update is needed or is being requested.
//!
//! This function detects if an update is being requested or if there is no
//! valid code presently located on the microcontroller. This is used to tell
//! whether or not to enter update mode.
//!
//! \return Returns a non-zero value if an update is needed or is being
//! requested and zero otherwise.
//
//*****************************************************************************
unsigned long
CheckForceUpdate(void)
{
#ifdef BL_CHECK_UPDATE_FN_HOOK
//
// If the update check function is hooked, call the application to determine
// how to proceed.
//
return(BL_CHECK_UPDATE_FN_HOOK());
#else
unsigned long *pulApp;
#ifdef ENABLE_UPDATE_CHECK
g_ulForced = 0;
#endif
//
// See if the first location is 0xfffffffff or something that does not
// look like a stack pointer, or if the second location is 0xffffffff or
// something that does not look like a reset vector.
//
pulApp = (unsigned long *)APP_START_ADDRESS;
if((pulApp[0] == 0xffffffff) || ((pulApp[0] & 0xfff00000) != 0x20000000) ||
(pulApp[1] == 0xffffffff) || ((pulApp[1] & 0xfff00001) != 0x00000001))
{
return(1);
}
#ifdef ENABLE_UPDATE_CHECK
//
// If simple GPIO checking is configured, determine whether or not to force
// an update.
//
return(CheckGPIOForceUpdate());
#else
//
// GPIO checking is not required so, if we get here, a valid image exists
// and no update is needed.
//
return(0);
#endif
#endif
}
//*****************************************************************************
//
//! Checks if an update is needed or is being requested.
//!
//! This function detects if an update is being requested or if there is no
//! valid code presently located on the microcontroller. This is used to tell
//! whether or not to enter update mode.
//!
//! \return Returns a non-zero value if an update is needed or is being
//! requested and zero otherwise.
//
//*****************************************************************************
uint32_t
CheckForceUpdate(void)
{
#ifdef CHECK_CRC
uint32_t ui32Retcode;
#endif
#ifdef BL_CHECK_UPDATE_FN_HOOK
//
// If the update check function is hooked, call the application to determine
// how to proceed.
//
return(BL_CHECK_UPDATE_FN_HOOK());
#else
uint32_t *pui32App;
#ifdef ENABLE_UPDATE_CHECK
g_ui32Forced = 0;
#endif
//
// See if the first location is 0xfffffffff or something that does not
// look like a stack pointer, or if the second location is 0xffffffff or
// something that does not look like a reset vector.
//
pui32App = (uint32_t *)APP_START_ADDRESS;
if((pui32App[0] == 0xffffffff) ||
((pui32App[0] & 0xfff00000) != 0x20000000) ||
(pui32App[1] == 0xffffffff) ||
((pui32App[1] & 0xfff00001) != 0x00000001))
{
return(1);
}
//
// If required, scan the image for an embedded CRC and ensure that it
// matches the current CRC of the image.
//
#ifdef CHECK_CRC
InitCRC32Table();
ui32Retcode = CheckImageCRC32(pui32App);
//
// If ENFORCE_CRC is defined, we only boot the image if the CRC is
// present in the image information header and the value calculated
// matches the value in the header. If ENFORCE_CRC is not defined, we
// the image if the CRC is good but also if the length field of the header
// is zero (which typically indicates that the post-build step of running
// binpack to add the length and CRC to the header was not run).
//
#ifdef ENFORCE_CRC
if(ui32Retcode != CHECK_CRC_OK)
#else
if((ui32Retcode != CHECK_CRC_OK) && (ui32Retcode != CHECK_CRC_NO_LENGTH))
#endif
{
//
// The CRC32 image check failed indicating that the image is
// corrupt (or doesn't have the CRC embedded correctly). Either way,
// fail the update check and force the boot loader to retain control.
//
return(2);
}
#endif
#ifdef ENABLE_UPDATE_CHECK
//
// If simple GPIO checking is configured, determine whether or not to force
// an update.
//
return(CheckGPIOForceUpdate());
#else
//
// GPIO checking is not required so, if we get here, a valid image exists
// and no update is needed.
//
return(0);
#endif
#endif
}
