Content originally posted in LPCWare by cwpjr on Wed Jul 17 10:54:34 MST 2013
In my experience your don't have a valid clock selected for input to the pll. it will never stabilize without an input clock.
My NXP 1114 board has an external 12mhz crystal and the CMSIS layer code for my board/chip (unmodified), the code you site here, chooses the external xtal, even though it's the same frequency as the internal clock.
2cents, hope it helps!