[ltp] Thinkpad X100e alternative BIOS, hardware info needed

Carl-Daniel Hailfinger linux-thinkpad@linux-thinkpad.org
Mon, 18 Oct 2010 23:31:51 +0200

On 18.10.2010 20:39, Henrique de Moraes Holschuh wrote:
> On Mon, 18 Oct 2010, Carl-Daniel Hailfinger wrote:
>> Thinkpad X100e might be a good target because people are complaining
>> about the existing BIOS, and because it has an AMD chipset for which
>> there is open documentation (sadly lacking for Intel chipsets).
> Don't forget the embedded controller... the firmware interface is not
> documented, and much of it runs in SMM.

That's one of the reasons I requested the output from superiotool. It
will detect a few ECs, and I have the docs for the IT8502 EC which
apparently is used in the X100e.
Even if we don't know the EC host interface in detail, it is doable to
find out the most important things by logging communication between the
EC and the host, and I'm willing to invest some time into that.
Unless the hardware is really screwed up, handling communication with
the EC can be done outside SMM, but it may require either ACPI or some
custom kernel driver. SMM is often used to emulate old interfaces to
keep old drivers working, and the benefits of that are debatable.