On 31/03/2019 07:14, nic.c3.14(a)gmail.com wrote:
I'm new to coreboot, and I'm trying to port it to the Dell Latitude E6400.
It is fairly similar to the Thinkpad T400, so I thought this would be a
relatively easy first project.
I am afraid I have bad news for you.
Laptops are usually harder to support because of
the limited debugging
interfaces, as well as having a controller which runs an undocumented,
machine-specific firmware: the Embedded Controller (EC). It controls the
keyboard, touchpad, battery, fan and power button, among other things.
Another issue this machine has is its memory: it uses DDR2, which is not
currently supported in coreboot's code for this laptop's chipset. Since the
relevant bits are not documented in any public datasheet, getting raminit
to work will be a very tedious job. It involves lots of failed boots and a
console to get debug logs from (harder to get one on laptops).
With that being said, porting this laptop is a daunting task. I would
strongly suggest picking up something else to begin with. I started with a
Sandy Bridge desktop mainboard, which are much easier to work with.