6.9 KiB
Vendor files not required for Dell Latitude E6400 if you have the Intel GPU.
If you have the Nvidia model, please use the e6400nvidia_4mb target, and
make sure to run the inject script.
E6400 nvidia issues
See: https://codeberg.org/libreboot/lbmk/issues/14#issuecomment-907758
If using Linux on Nvidia GPU variants of E6400, please boot using nomodeset.
The nv drivers on BSD systems generally work, but can have severe performance
issues; use of a tiling window manager is recommended, on BSD systems, because
moving windows around can literally lag a lot otherwise, on most window managers.
dGPU variants
On everything except E6400, Libreboot only supports the variant with an Intel GPU. Therefore, you must only purchase a Dell Latitude that has the Intel graphics; even on E6400, this is good advice, due to issues with the Nvidia GPU on E6400, documented later in this guide.
Internal flashing
You can simply boot Linux/BSD, on the Dell Latitude you wish to flash, and
run flashprog from there, for Libreboot installation. Certain other steps
are also required, documented in the steps below:
You can flash Libreboot directly from the vendor (Dell) BIOS, without taking the machine apart. It can be done entirely from Linux/BSD.
NOTE (15 October 2023): The util is now called dell-flash-unlock, but it
was previously called e6400-flash-unlock. Links have been updated.
Check util/dell-flash-unlock in the lbmk.git repository, or in release
archives for Libreboot releases from 20230423 onwards.
Go in there:
cd util/dell-flash-unlock
make
With this program, you can unlock the flash in such a way where everything
is writeable. Information about how to use it is in the README.md file which
is included in that program's directory, or you can read it online here:
https://browse.libreboot.org/lbmk.git/plain/util/dell-flash-unlock/README.md
Please make sure that you do fully read the README, because it contains useful information.
Literally just run that program, and do what it says. You run it once, and shut
down, and when you do, the system brings itself back up automatically; on some
systems, you have to boot the machine back up manually, after power down. Then
you run it and flash it unlocked. Then you run it again. The source code is
intuitive enough that you can easily get the gist of it; it's writing some EC
commands and changing some chipset config bits. The EC on this machine is
hooked up to the GPIO33 signal, sometimes called HDA_DOCK_EN, which sets
the flash descriptor override thus disabling any flash protection by the IFD.
It also bypasses the SMM BIOS lock protection by disabling SMIs, and Dell's
BIOS doesn't set any other type of protection either such as writing to
Protected Range registers.
MAKE SURE to back up the original firmware image first:
flashprog -p internal -r factory.rom
When you flash it, you can use this command:
flashprog -p internal -w libreboot.rom
Where libreboot.rom is your Dell Latitude ROM. Make sure it's the right
one. If flashprog complains about multiple flash chips detected, just pick one of them (doesn't matter which one). On most Dell machines, the most correct
would probably be this option in flashprog: -c MX25L3205D/MX25L3208D.
So:
flashprog -p internal -w libreboot.rom -c MX25L3205D/MX25L3208D
When you see flashprog say VERIFIED at the end, that means the flash was
successful. If you don't see that, or you're unsure, please contact the
Libreboot project via IRC.
External flashing
General guidance
Machine-specific disassembly instructions not provided, but you can find the hardware maintenance manual for your Latitude module online. Just search for it. The flash chips(s) is/are usually under the keyboard/palmrest. Near to the PCH/southbridge.
Note that you often have to provide a high current for VCC, because the flash chip will share a common voltage rail with other power-hungry ICs on the board, or the flash ICs will share a common MISO/MOSI line without resistance, with chip selects controlled by PCH, and/or the PCH itself might be live while flashing - so you need to set the drive strength high.
Take stock of the above advice, which is also mentioned on the external SPI flashing guide.
Please read the external SPI flash guide
External flashing is usually not required, on these machines.
Chip size guidance
SOme Dell Latitudes use a single flash chip, so you can just use the ROM images as-is.
If there are two flash chips, you must split the ROM images. Check the silk screen on the board, and the first chip might be labelled something like SPI1, second one SPI2. Figure out which one is first.
Look at the part number on the chip and find the flash size for it. For example: a 10MB flash might be 2MB for SPI1 and 8MB for SPI2, so you would do:
dd if=libreboot.rom of=spi1.rom bs=1M count=2
dd if=libreboot.rom of=spi2.rom bs=1M skip=2
Adapt accordingly, to the exact flash configuration on your machine. 16MB is likely one chip. 12MB is usually SPI1 8MB and SPI2 4MB so you would do:
dd if=libreboot.rom of=spi1.rom bs=1M count=8
dd if=libreboot.rom of=spi2.rom bs=1M skip=8
If in doubt, just ask on Libreboot IRC.