How to contribute to linker command file generation

Sandeep,
that linker command file is a result of running a RTSC configuration script. A script loads various RTSC packages and each package can contribute to the linker command file. If a package only needs to add a library (or multiple libraries), a package may implement the function getLibs. The link contains more details about that function.
To add some other content to the generated linker command file, a package can use the function getSects. The name of the function hints that it's mainly used to add section allocations to the linker command file, but in reality a package can add any arbitrary content that is understood by the linker. This function requires an additional XDC template file, details are in the linked documentation.

A RTSC configuration script can also directly contribute to the linker command file. Here are some parameters that are used for that:
http://rtsc.eclipse.org/cdoc-tip/xdc/cfg/Program.html#sections.Exclude
http://rtsc.eclipse.org/cdoc-tip/xdc/cfg/Program.html#sections.Template
http://rtsc.eclipse.org/cdoc-tip/xdc/cfg/Program.html#link.Template

Here is one more link to give you a general idea what happens within RTSC configuration flow:
http://rtsc.eclipse.org/docs-tip/RTSC_Module_Primer/Lesson_1#Configuring_RTSC_programs