ST.com published a news about release CubeMX and AC6 (http://openstm32.org) software for Linux operating systems.
CubeMX is software for faster and easier development of projects with STM32. The program generates project with all needed libraries which you can modify for your needs. The project can be generate for Keil, IAR, SW4STM32 (AC6), TrueStudio and another.
AC6 is IDE based on Eclipse - now is available for everyone.

http://www.st.com/web/en/press/p3781