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% Dell Latitude E6400 added (blob-free, no disassembly) % Leah Rowe % 19 April 2023

UPDATE (9 May 2023): Libreboot confirmed working on variants such as E6400 XFR, and the Nvidia GPU variant is now supported.

Introduction

Today, Libreboot gained the Dell Latitude E6400 laptop port. This is a blob-less port, courtesy of Nicholas Chin (nic3-14159 on Libreboot IRC). Nicholas has worked extensively on this port, for several years, and it's in a ready state for entry to Libreboot.

The hardware platform is GM45, similar to ThinkPad X200, T400 and so on that Libreboot already supports.

You can learn more on the Latitude flashing guide

100% libre, blob-free

This is a blob-free board in the boot flash. No Intel ME firmware needed, and microcode can be removed if you wish (you should still leave microcode there, as is default, but some people remove it by choice that we give them - see: Binary Blobs Reduction Policy).

But wait. There's more. A lot more of them, that is.

Readily available on eBay etc, and cheap

Dells were much more popular than those ThinkPads, and more commonly used, so there are still several of these available on sites like eBay. Enough to keep people with an affinity for GM45 machines happy for a while longer (older GM45 ThinkPad X200, T400 etc are very hard to find nowadays).

This could very well replace X200, T400 etc, in terms of what certain people want to use - nice enough screen/keyboard, and easy of installation just makes this a very nice machine indeed.

But wait.... It gets better:

Software flashing possible! (no disassembly)

NOTE (15 October 2023): The util is now called dell-flash-unlock, but it was previously called e6400-flash-unlock. Links have been updated. And Nicholas is still a genius.

tl;dr Nicholas is a genius, but he spent time studying the board, finding that the EC is hooked up to GPIO33 which allows for flash descriptor override. He successfully reverse engineered a command that can be used to disable IFD protections, and discovered that the SMM BIOS lock protection could be bypassed, allowing installation of Libreboot.

This is without needing to disassemble. No clip required.

That is to say, you can install Libreboot on this board without taking it apart, and you can install it easily within 5 minutes.

This is done with the following utility from Nicholas Chin, which I merged into lbmk:

https://browse.libreboot.org/lbmk.git/tree/util/dell-flash-unlock

The original util, before Nicholas sent it to lbmk, is here (same util):

https://gitlab.com/nic3-14159/e6400-flash-unlock/-/commits/base

It merges some code changes that I made myself, after Nicholas published it, tidying up the code a bit (OpenBSD-like coding style adopted, for fun). See:

https://codeberg.org/vimuser/e6400-flash-unlock/commits/branch/puffy

Libreboot users should use the one in util/ on Libreboot proper.

That is all! Read the manuals to know more about this machine. Thank you!