Dear Mohamed,
If you already solved the steady state in a Matlab-file, you can use it directly. As the user guide says:
[quote]The alternative is to write a Matlab program to find your model’s steady
state. Doing so has the clear advantages of being able to incorporate your
Matlab program directly into your .mod file so that running loops with differ-
ent parameter values, for instance, becomes seamless. NOTE! When doing so,
your matlab (.m) file should have the same name as your .mod file , followed
by _steadystate. For instance, if your .mod file is called example.mod, your
Matlab file should be called example_steadystate.m and should be saved in
the same directory as your .mod file. Dynare will automatically check the di-
rectory where you’ve saved your .mod file to see if such a Matlab file exists. If
so, it will use that file to find steady state values regardless of whether you’ve
provided initial values in your .mod file.[/quote]
For an example how to do it and for a program to add the required code to import and export both the parameters and the steady state values to Dynare, see the post:
Best,
Johannes