Have you tried recovery mode?
This has been discussed may times on these forums.
If you don't know how to get to recovery mode, here's the guide (that I quickly Googled):
Step 1: Turn off your Playstation 3.
Step 2: Hold the Power button down. The system will turn on and turn off once again.
Step 3: Once the system has been shutdown, Re-press and hold you finger until you hear 2 consecutive beeps.
Step 4: When you hear the 2 beeps take finger off power button. You will be promted to plug in your controller via usb and then press the PS button. The Recovery Menu will pop up.
Recovery Menu Features:
Restore Default Settings.Restores all settings to default on the PS3, Networking, time zone, video, etc. This same of the Restored Settings under XMB > Settings > System Settings > Restore to Defaults on your console. This should not eliminate your game saves or other saved content, including your user login.
Restore File System.
This will rewrite the files of PS3 used to boot. This feature will help if PS3 firmware become corrupted or semi brick. This should not Delete any of your saved data and settings.
This can be a usefull feature if you have lost files on your system for no apparent reason. Try using this feature to see if it can restore those files. This will also overwrite corrupted files within the database, This feature should not erase any of your saved data or settings.
Restore PS3 System.This will restore your system firmware to original including, formatting harddrive and delete all of the data on the HDD and restore all system settings to default. This will not take your system back to a previous Firmware release. Use this feature if your PS3 firmware become corrupted or semi brick, This feature may require the ps3 update data inserted on a usb drive..
System Update.This will allow the user to update their PS3 console with new firmware in same version or higher via a USB Flash drive or other portable media, this will not allow you to update via an internet connection. This can usefull if your PS3 firmware become corrupted or semi brick to the point PS3 can not boot. You will need a USB Flash drive or portable media device with the correct firmware and in the correct file structure to complete the update.
That said, chances are your PS3 will still be corrupt. (Welcome to the club, I've had this happen several times!)
In that case, I recommend removing your HDD from the console and reformatting it via a PC but I'd use specific formatting software (freeware is OK).
Stick the drive back in the console and update to OFW 3.55 first and then to any CFW of your fancy.
Hopefully, you would have backups of everything that you can now restore. If not, now's a good time to start.
By far most corruptions occur when the PS3 loses power whilst it's writing to the HDD. Keep this in mind too.
"We all agree your theory is crazy, but is it crazy enough?" - Neils Bohr