Firmware Fallback Feature - Enable#

The Master Boot Record (MBR) defines flash-partition layout. Enabling fallback rewrites the partition table to include dual-slot regions and slot metadata, so reprovisioning the MBR is mandatory to enable/disable the Firmware Fallback feature.

Important:
After enabling the Firmware Fallback feature, only host-based or M4-based Over-the-Air (OTA) firmware updates are supported. Other firmware update methods mentioned in AN1431: SiWx917 Firmware Update App Note, such as HTTP OTAF and Kermit/Simplicity flashing, are not supported.

Devices with default MBR#

To enable firmware fallback feature, update the MBR following the below steps:

1. Update the NWP firmware in SiWG917, to the latest version available.

   • The NWP firmware version must be greater than or equal to v1711.2.14.5.2.0.7

   Note: Ensure the Simplicity Commander is updated to the latest version (1.19.2)

2. Update the MBR using the command below in Simplicity Commander CLI, to enable Firmware Fallback feature:

   commander manufacturing provision --mbr default --profile fallback -d SiWG917M111MGTBA

To check whether the firmware fallback feature is enabled, read value at flash location 0x4000091, using the below Commander CLI command. Value 1 indicates firmware fallback feature is enabled:

commander readmem --range 0x4000091:+1

Devices with custom MBR#

The MBR provisioning gives multiple options to user such as enabling different levels of security, enabling/disabling anti-rollback. To enable firmware fallback feature in such scenarios, follow the below steps:

1. Load the standard slot-A NWP firmware in SoC, via Simplicity Commander (or any other firmware update process)

   • The NWP firmware version must be greater than or equal to SiWG917-B.2.14.5.0.0.8.rps

   Note: Ensure the Simplicity Commander is updated to the latest version (1.18.2)

2. Append --profile fallback to the MBR provisioning command used for the SiWG917 according to your usercase. An example command is given below for reference.

   commander manufacturing provision --mbr device_mbr.bin --keys device_keys.json --device SiWG917Y111MGABA --profile fallback

   Note: In the above command, device_mbr.bin is the MBR file, and device_keys.json file contains fields of MBR that needs an update, such as security levels. Refer UG574: SiWx917 SoC Manufacturing Utility Userguide for more information.

To check whether the firmware fallback feature is enabled, read value at flash location 0x4000091, using the below CLI command. Value 1 indicates firmware fallback feature is enabled:

commander readmem --range 0x4000091:+1

Refer to the image below to enable the Firmware Fallback Feature using the default MBR: