If your console isn't online, you can download the update file from the official PlayStation Support site . Preparation: Use a FAT32-formatted USB drive.
The safest way to get the firmware is through official channels:
To update your PS3 Super Slim Go to product viewer dialog for this item.
If you are looking for custom firmware (CFW) or homebrew for a Super Slim model, keep in mind: How to update PS3 console system software - PlayStation
Navigate to Settings > System Update > Update via Internet .
Save the downloaded file exactly as PS3UPDAT.PUP in the UPDATE folder.