Flashing the Dell Latitude E6400

Return to index


Initial flashing instructions for the E6400. DO NOT flash the Nvidia GPU variant. This page pertains only to the Intel GPU variant.

This guide is for those who want Canoeboot on their Latitude E6400 while they still have the original Dell BIOS present. This guide can also be followed (adapted) if you brick your E6400, and you want to recover it.

This board can boot entirely blob-free in the flash. The hardware is similar to that of ThinkPad X200, T400 etc where no-ME setup is possible.

A note about GPUs

Models with Intel graphics are GM45, and fully supported in Canoeboot with native initialisation; ROM images are available since. The Intel video initialisation is libre, implemented with publicly available source code via libgfxinit, from the coreboot project.

Flash chip size

Use this to find out:

flashprog -p internal

We believe most/all are 4MB (32Mb) flash sizes, but larger ROM images are provided for people who wish to upgrade.

MAC address

The MAC address is part of the ROM image that you’re flashing. You can change it at any time, before or after you’ve flashed Canoeboot; you can also change it in the Dell BIOS, if you really want to. This is for the onboard gigabit ethernet device.

Refer to mac_address.html.

It is recommended that you run nvmutil. See:

nvmutil usage manual

The nvmutil software is specifically designed for changing MAC addresses, and it implements a few more safeguards (e.g. prevents multicast/all-zero MAC addresses) and features (MAC address randomisation, ability to correct or intententionally corrupt(disable) GbE sections if you wish, swap GbE parts, etc). You can also run ich9gen, if you wish:

ich9gen usage manual

Intel GPU: libre video initialisation available

Canoeboot uses coreboot’s native libgfxinit on this platform, for variants with Intel graphics.

How to flash internally (no diassembly)

Flashing from GNU+Linux

MAKE SURE you boot with this Linux kernel parameter: iomem=relaxed - this disables memory protections, permitting /dev/mem access needed by flashprog. The flash is memory mapped and flashprog accesses it via /dev/mem.

You can flash Canoeboot directly from the vendor (Dell) BIOS, without taking the machine apart. It can be done entirely from GNU+Linux. It will probably also work on BSD systems, but it has only been testing on GNU+Linux thus far.

NOTE: 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 cbmk.git repository, or in release archives for Canoeboot releases from 20231026 onward.

Go in there:

cd util/dell-flash-unlock

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.html file which is included in that program’s directory, or you can read it online here:


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. 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.

When you flash it, you can use this command:

flashprog -p internal -w canoeboot.rom

Where canoeboot.rom is your E6400 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.


flashprog -p internal -w canoeboot.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 Canoeboot project via IRC.


The -w option flashes canoeboot.rom. You may consider backing up the original Dell BIOS first, using the -r option:

flashprog -p internal -r backup.rom -c MX25L3205D/MX25L3208D

Do this while in a flashable state, after the 2nd run of dell-flash-unlock.

Make sure the backup.rom file gets backed up to an external storage media, not the E6400 itself.

With this method, you can probably flash it within 5 minutes. Again, zero disassembly required!

How to flash externally

Refer to spi.html as a guide for external re-flashing.

The SPI flash chip shares a voltage rail with the ICH9 southbridge, which is not isolated using a diode. As a result, powering the flash chip externally causes the ICH9 to partially power up and attempt to drive the SPI clock pin low, which can interfere with programmers such as the Raspberry Pi. See RPi Drive Strength for a workaround.

Have a look online for videos showing how to disassemble, if you wish to externally re-flash.

Markdown file for this page: https://canoeboot.org/docs/install/e6400.md

Subscribe to RSS for this site

Site map

This HTML page was generated by the Untitled Static Site Generator.