Comments on: Harrowing Story of Installing Libreboot on ThinkPad

By: Thái

Thái — Mon, 20 Feb 2017 06:54:21 +0000

What?
Need to open my laptop up to install new free BIOS?
No thanks sir. I need to be free, I need my laptop more.

By: asdf

asdf — Thu, 22 Dec 2016 09:02:16 +0000

Systems management mode can be entered via an external pin, but why do you assume that the external controller is injecting code, rather than the functionality being present in the BIOS (which is responsible for setting up the SMM handler in the first place)?

Lenovo’s choices of embedded controllers are well documented on sites like ThinkWiki etc.

By: nob

nob — Tue, 20 Dec 2016 21:28:17 +0000

I’ve been slowly following this same adventure myself for several on/off months. Most of my headache has been the same story – piss-poor documentation that takes great assumptions in the reader’s prior knowledge, linux being linux (awful distro I won’t use, distro I would use won’t install, distro I knew worked stopped working, etc), complete ambiguity of what the next step is at several points. Trying to do it all from within windows before making the jump to linux might well just be a pipe-dream. Glad to see a post about coreboot/libreboot on HAD at least though, thanks for the write-up

By: nob

nob — Tue, 20 Dec 2016 21:23:45 +0000

With regards to clock throttling on C2D thinkpads, on some units when plugged into the 65W adapter, will throttle clockspeed when also plugged into a bad battery. Can be forced to full speed with throttlestop, plugging into a 90W adapter instead, getting a good battery, or all three.
Cheers

By: Unferium

Unferium — Tue, 20 Dec 2016 13:32:20 +0000

Dunno why I’m replying since this is now an old post…. a day passed before you commented so I missed the main opportunity…

However if you do see this thread again:
In my Dell, the EC is connected to some interrupt lines and I recall some #reset lines also.(where did I save those schematics?)

The EC will interrupt the CPU and call SMM functions when entering a thermal debug mode…

Holding Shift and FN then typing 15324 enables EC into a kind of debug mode and FN + R or FN + T pauses Ring 0 (OS Kernel, my mental memory is stale about ring levels though) execution and shoves some payload into the memory (SMBIOS? BIOS-reserved?) area to display the thermal debug pages (EC controls all thermal and SMBUS in the laptop)

If the EC is completely seperate and thus has no hypervisor capability then explain this.

P.s. works on older Intel architecture where those CPU control lines are exposed between the CPU and the Northbridge (MCH/PCH in some systems).
The newer embedded core i# don’t seem to show the pages confirming the missing control lines even though the LED flashes to indicate the EC has entered this mode.

A lot can be learnt from schematics (if available for your current model)

By: asdf

asdf — Tue, 20 Dec 2016 09:09:37 +0000

Unless you’re planning on designing and fabbing your own chips (preferably in your own fab), RISC-V isn’t going to change anything. The best you can do is decap and reverse-engineer from die photos, and the only thing that will tell you is if the chip you just destroyed had anything unexpected in it.

TPM is what protects you from evil maids.

By: anonymous

anonymous — Tue, 20 Dec 2016 01:09:51 +0000

No takesies-backsies! Anyway, if she wanted protection of her project, she should’ve A. found out what she was getting into by joining GNU, and B. trademarked the name.

Not to mention C. don’t start a shitstorm without so much as getting the allegedly discriminated-against person to come forward.