Miroslav,
You will need to register an account with us and then register your kit to that account. Once you have access to the downloads you can download the Linux User's Guide[1] or download the VM[2][3] which has the build environment all setup.
From the Linux User's Guide:
There are many places on the Internet where you can find the source code to U-Boot and the Linux
kernel.
Finding the appropriate package for your hardware can be difficult. One method is to:
1. Log in to the TI website.
2. Use the Keyword Search box to search for Linux PSP.
3. Filter the search results by Software & Tool Folders.
4. Find a heading that mentions Linux for
Devices.
5. Follow that link to an appropriate *.tgz file.
Method two is:
1. Log in to the TI website.
2. Use the Search by Part Number box to search for the processor you are using.
3. Locate the product folder for the processor.
4. Follow the Software & Tools link.
[1] http://support.logicpd.co...d=0&EntryId=1424
[2] http://support.logicpd.co...id=0&EntryId=988
[3] http://support.logicpd.co...d=0&EntryId=1426 VM README