Pavel:
Sorry I missed you were using IAR EWARM. Under your project, right click on I in the workspace area, the Options, General, Library config.
I would start with NORMAL and Semihosted at the bottom. I use this on new projects. It sort of intercepts some low level calls (ie uart IO) and sends the output to the debugger terminal window so you can get board output up ASAP.
If you want to run completely from flash, like a real product, the select Normal, None (vs semi-hosted). Then you'll have to provide your own low level UART io from your BSP/SDK and write a little code to glue that into printf to get serial output.
The other config file (.icf) file shouldn't need to be changed. That tells the linked where your code will flash to and where RAM is on your board. You can also add link level defines for specific sections of code to live at fixed addresses.
Good luck,
Larry