T23x Boot Configuration Table

The Boot Configuration Table (BCT) is a set of platform-specific configuration data that is consumed by a boot component. BootROM and MB1 consume BCT in binary form, which is generated by using the parsing device tree source configuration files, with a .dts file extension, by tegrabct_v2.

Starting from T23x, the config file format changed from legacy <parameter> = <value>; to Device Tree Source (DTS) format for the following reasons:

  • DTS format supports recursive inclusion and the overriding of properties though inclusion.

  • DTC can covert DTS/DTSI to DTB, which is a tree-like format, and is easier to parse than the current config file format.

BR-BCT

BR-BCT is loaded by BootROM from storage in coldboot mode and by MB1 in recovery mode. The primarily consumer of this BCT is BootROM, but some fields are also consumed by MB1 and CPU-BL.

MB1-BCT

MB1 BCT is loaded by MB1 from storage (in coldboot mode) or over USB (in RCM mode), is primarily consumed by MB1, and is constructed from the following configuration files:

Mem-BCT

Mem-BCT is like MB1-BCT in terms of loading and usage. However, Mem-BCT primarily contains SDRAM parameters that are used to initialize MC and EMC. Refer to SDRAM Configuration for more information.

MB2-BCT

MB2 BCT is loaded by MB1 from storage (in coldboot mode) or over USB (in RCM mode). It is primarily consumed by MB2 and is constructed out of the following configuration files: