How to program SoC chips like CC2541F128RHAT
Official tools are listed at TI's site http://www.ti.com/product/CC2541/toolssoftware

You need an 8051 toolchain (compiler and friends). You also need a programmer like the CC-DEBUGGER. There may be some software that can bit-bang an FTDI chip to program the CC2541.

Development kit is the easiest option to get started with a new chip.