A Mstar upgrade binary consists of a firmware installation script and a payload.
The firmware installation script is executed by the TV and is used to setup partitions and extract various portions of payload, optionally decompressing said portions, and then flash them to partitions on the TV's eMMC flash memory.
The firmware installation script can also be used to customise the environment (i.e. environment variables) on the device.
Example Memory Map from a Kogan Upgrade Image
0x0000 - 0x4000: Firmware Installation Script
0x4000 - 0x635D1A: U-Boot Multi-Part uImage [(gzip) Linux Recovery Kernel, (gzip) Recovery initramfs] -> recovery
0xA04000 - 0xDA1B75: U-Boot Multi-Part uImage [(gzip) Android/Linux Kernel, (gzip) Android initramfs] -> boot
0xE04000 - 0x19E04000: (Uncompressed) Android System Partition -> system
0x19E04000 - 0x1A874BE7: (lzo) Android Userdata Partition -> userdata
0x1A884000 - 0x1A9B867B: (lzo) Android Cache Partition -> cache
0x1a9C4000 - 0x1F9C4000: (Uncompressed) Mstar TVService Partition -> tvservice
0x1F9C4000 - 0x209C4000: (Uncompressed) Mstar TVCustomer Partition -> tvcustomer
0x209C4000 - 0x211C4000: (Uncompressed) Mstar TVDatabase Partition -> tvdatabase
0x211C4000 - 0x241C4000: (Uncompressed) Mstar Customer Config Partition -> customercfg