12.6 Application Transition
After loading and authenticating a valid image, the ROM firmware must perform several additional setup steps before transitioning to the application.
- Remap interrupt and exception vectors to the application space addresses.
- Set the SEC_BOOT_DONE configuration register bits.
- Jump to application code at FW_IMG_DST_ADDR.
The ROM firmware programs the SECBOOTDONE bits to 0b11 when the firmware image is validated and before switching to the application. The BOOTSTATUS bits will be programmed with the firmware at each step and will indicate firmware status while trying to load the firmware.
| Code | Value | Description |
|---|---|---|
| DSU Mode | ||
| TMODE_PE | 0x02 | System is in Parallel Execution Mode |
| TMOD_LOCK_DOWN | 0x03 | System is in Test Lock Down Mode; check for secondary status code. |
| Secure Boot | ||
| SYS_FW_AUTH | 0x04 | System is currently authenticating the firmware; do nothing. |
| SYS_FW_LOAD | 0x05 | System is loading or programming the firmware image; do nothing. |
| SYS_APP_MODE | 0x06 | System is in application mode; a firmware image is loaded and is running. |
| SYS_LOCK_DOWN | 0x07 | System is Locked down; check secondary status. |
| Code | Value | Description |
|---|---|---|
| TMOD_LOCK_DOWN | ||
| TMOD_8_10 | 0x00 | System is in TMOD 8 or TMOD 10. Proceed with Factory reset. |
| ERR_BAD_TMOD | 0x01 | System does not support this test mode; reset the device. |
| SYS_LOCK_DOWN | ||
| SYS_LD_ERR_FW_AUTH_FAIL | 0x00 | Reset the device and program a valid firmware image. |
| SYS_LD_ERR_NO_FW_IMG | 0x01 | Reset the device and program a valid firmware image. |