diff options
Diffstat (limited to 'Bootloaders/MassStorage/BootloaderMassStorage.c')
| -rw-r--r-- | Bootloaders/MassStorage/BootloaderMassStorage.c | 47 |
1 files changed, 46 insertions, 1 deletions
diff --git a/Bootloaders/MassStorage/BootloaderMassStorage.c b/Bootloaders/MassStorage/BootloaderMassStorage.c index 28f42b6d2..1b6eda438 100644 --- a/Bootloaders/MassStorage/BootloaderMassStorage.c +++ b/Bootloaders/MassStorage/BootloaderMassStorage.c @@ -33,6 +33,7 @@ * Main source file for the Mass Storage class bootloader. This file contains the complete bootloader logic. */ +#define INCLUDE_FROM_BOOTLOADER_MASSSTORAGE_C #include "BootloaderMassStorage.h" /** LUFA Mass Storage Class driver interface configuration and state information. This structure is @@ -60,7 +61,30 @@ USB_ClassInfo_MS_Device_t Disk_MS_Interface = }, }; +/** Flag to indicate if the bootloader should be running, or should exit and allow the application code to run + * via a soft reset. When cleared, the bootloader will abort, the USB interface will shut down and the application + * started via a forced watchdog reset. + */ +bool RunBootloader = true; + +/** Magic lock for forced application start. If the HWBE fuse is programmed and BOOTRST is unprogrammed, the bootloader + * will start if the /HWB line of the AVR is held low and the system is reset. However, if the /HWB line is still held + * low when the application attempts to start via a watchdog reset, the bootloader will re-start. If set to the value + * \ref MAGIC_BOOT_KEY the special init function \ref Application_Jump_Check() will force the application to start. + */ +uint16_t MagicBootKey ATTR_NO_INIT; + +/** Indicates if the bootloader is allowed to exit immediately if \ref RunBootloader is \c false. During shutdown all + * pending commands must be processed before jumping to the user-application, thus this tracks the main program loop + * iterations since a SCSI command from the host was received. + */ +static uint8_t TicksSinceLastCommand = 0; + +/** Special startup routine to check if the bootloader was started via a watchdog reset, and if the magic application + * start key has been loaded into \ref MagicBootKey. If the bootloader started via the watchdog and the key is valid, + * this will force the user application to start via a software jump. + */ void Application_Jump_Check(void) { bool JumpToApplication = false; @@ -90,6 +114,13 @@ void Application_Jump_Check(void) JTAG_ENABLE(); #endif + /* If the reset source was the bootloader and the key is correct, clear it and jump to the application */ + if ((MCUSR & (1 << WDRF)) && (MagicBootKey == MAGIC_BOOT_KEY)) + { + MagicBootKey = 0; + JumpToApplication = true; + } + if (JumpToApplication) { // cppcheck-suppress constStatement @@ -107,11 +138,22 @@ int main(void) LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); GlobalInterruptEnable(); - for (;;) + while (RunBootloader || TicksSinceLastCommand++ < 0xFF) { MS_Device_USBTask(&Disk_MS_Interface); USB_USBTask(); } + + /* Disconnect from the host - USB interface will be reset later along with the AVR */ + USB_Detach(); + + /* Unlock the forced application start mode of the bootloader if it is restarted */ + MagicBootKey = MAGIC_BOOT_KEY; + + /* Enable the watchdog and force a timeout to reset the AVR */ + wdt_enable(WDTO_250MS); + + for (;;); } /** Configures the board hardware and chip peripherals for the demo's functionality. */ @@ -189,5 +231,8 @@ bool CALLBACK_MS_Device_SCSICommandReceived(USB_ClassInfo_MS_Device_t* const MSI CommandSuccess = SCSI_DecodeSCSICommand(MSInterfaceInfo); LEDs_SetAllLEDs(LEDMASK_USB_READY); + /* Signal that a command was processed, must not exit bootloader yet */ + TicksSinceLastCommand = 0; + return CommandSuccess; } |