Hello Youngho,
In the previous post, http://e2e.ti.com/support/low_power_rf/f/538/t/262209.aspx, there was the mention of the Core Bluetooth v4.0 from Bluetooth.org. There should also have been a reference to the TI CC254x BLE Software User's Guide SWRU271D.pdf. Inside that document, section 3.3.1 you will find information about the mutiroles.
To my knowledge, the peripheral- broadcaster and central-observer roles are supported. The guide mentions that simultaneous advertising and/or scanning while in a connection as either a master or a slave. This allows for a central device to perform device discovery while in a connection.
There is a table in section 3.3.5 of the guide that shows which library files are required for the different role combinations.
Thanks,