Hi,
In addition to that you can run OMAPL138_LCDK at 300MHz also,
Try to change the TCLK to 1MHz in target config advanced settings.
The same issue has been already raised and got closed.
Please have a look at it.
http://e2e.ti.com/support/development_tools/code_composer_studio/f/81/p/287359/1002614.aspx
http://e2e.ti.com/support/development_tools/code_composer_studio/f/81/p/321715/1132224.aspx
http://e2e.ti.com/support/dsp/omap_applications_processors/f/42/p/324873/1131793.aspx