Yes! Thank you for also lending a hand in 7537 BIOS modding!
I don't have much experience with modding. I've tried extensively to make a mod for this laptop, and just gave up after a while. Sorry
Here are some tips that I used to learn more about modding this BIOS:
STEP ZERO: In your BIOS, DISABLE Secure Boot and ENABLE legacy (OPROM/MBR) booting. It will let you boot into DOS for flashing the BIOS or enable the use of some tools.
1. Try some earlier versions available on Dell's website like A12 or A11 to see if there's anything that has changed or made easier. Not much of a help, but hey, you might be lucky! (The BIOS is not a SecureCore Tiano BTW, just plain ol' SecureCore, which means the BIOS might be RSA-encrypted)
2. Extract the BIOS .rom file directly from the .exe file (you could either use BIOS Backup Tools or run the EXE file and go into your %appdata% folder. There will be some folder inside that folder that says something like "DOH50A13.rom" or "DellInc.-A13.rom" which is the original ROM file you're looking for.
3. Use
AndyP's SLIC tool (you will need a MyDigitalLife account to view it) and read its manual for more information. The Phoenix BIOS Editor tool did no good for me; as for flashing, neither the manual WinPhlash tool or the Phoenix UEFI Flash tool worked, unfortunately.
4. You should get yourself a
UEFI shell -- it can help you change some values of the system (maybe edit the NVRAM, perhaps?).
You should not create a keypress shortcut as described in the
XPS 15 L15z article; it does not work.
However, you can create a boot option in the BIOS menu -- simply boot into the USB thumb drive, type fs1:, copy the Shellx64.efi file onto (fs0:?) whichever filesystem is your main hard drive or SSD (cp shellx64.efi fs0:/EFI) and add it as a boot option in the Boot menu (call it Shell, press tab until your main SSD or HDD is highlighted, then type EFI\shellx64.efi or something like that).
5. Use donovan6000's
Universal IFR Extractor to get information on DXEs or modules in plain English (maybe exploit the OP_SURPRESS_IF 0 --> 1 part for advanced options?).
The DellSplashLogoDxe module is for the awful UEFI Dell logo. (Rant) At least give us an option to disable it or have some kind of business tool like you did before, Dell! The logo burns my eyes, especially when booting from an HDD! (End Rant)
The (DellAdvancedSetupDxe?) PlatformHiiAdvancedDxe file has the hidden and locked "advanced options". You can extract it manually (it will create some kind of .DUMP file) in AndyP's SLIC tool.
6. Try flashing BIOSes in DOS. It may not work, as with me, Phlash16.exe said it was an "invalid BIOS file" :/
7. Based on what BDMaster said, you can use a SPI programmer, however I wouldn't recommend it.
It's a very "cheaty" way of modifying the BIOS; on the other hand, an SPI programmer can help you learn more about the underlying BIOS and change hex codes directly.
8. Here's
another useful resource (a WIP) that might help you out a little bit (an unlocking guide for Phoenix BIOSes).
9. Overclocking
may require all-out SPI programming because of the chip's security. It
may not be needed at all, though.
10. Words of wisdom: Persistence is key. Good luck.
NOTE: Upon installing and using the UEFI shell, transferring to an SSD from a HDD made some weird console underline thingy appear upon booting. This is normal when Secure Boot is disabled.