I had some work for FPGA on Windows, but now I want to change the platform to Linux. I am looking for some VHDL IDE instead of Xilinx?
There's a big difference between the IDE (development environment) and the simulator. The IDE might come without a built-in simulator, and the simulator might come without a GUI.
If you're looking for a simulator, here is a list of free VHDL simulators with download links. Most simulators work on Linux too.