[coreboot] X230 coreboot potential issues?

[Nico Huber]

Hi,

On 27.10.2017 22:10, Hans Fritz wrote:
> Hi, I installed coreboot on my X230, it works very well except for
> these two things:
> 
> When the screen goes to sleep and I move the mouse to wake it up, it
> wakes up at full brightness regardless of what the setting was before
> it went to sleep. If I press the button to lower or increase
> brightness, it switches back to what it was before sleeping. This
> didn't happen with the same Linux install but on the stock BIOS.

this is a known issue. It actually was there all the time but only
got more visible with the introduction of ACPI/OpRegion for the inte-
grated GFX. Here is what I found out so far (on my ArchLinux):

w/o OpRegion:
   1. `acpi_video` driver gets loaded, systemd restores brightness from
      last shutdown.
   2. `i915` driver gets loaded, reads the current brightness.
   3. `i915` exposes backlight as `intel_backlight`, systemd restores
      brightness from last shutdown here as well.

Every time `i915` power cycles the backlight, it restores the value it
has seen when it was loaded.

w/ Opregion the order somehow changes to 2. 1. 3., now `i915` always
restores to 100% that it read before systemd restored the brightness.

A sane solution would be to extend XBCM in `src/drivers/intel/gma/acpi/
configure_brightness_levels.asl` to always notify `i915` when we change
the backlight through OpRegion mailbox 3.

> 
> The Fn key used to wake up the computer, but it doesn't anymore. Most
> Fn key combinations still work, except for Fn+F3 (lock screen). This
> was fine with the same Ubuntu install and the stock BIOS.

IIRC, this is configurable in the vendor BIOS and likely a option in the
EC that nobody missed enough to implement it in coreboot. Might be as
simple as h8_fn_ctrl_swap(). Fn+F3 might just need a little more ACPI
code.

> 
> Any thoughts? Are these issues with coreboot? Should I file an issue somewhere?

Yes please, https://ticket.coreboot.org/

Nico