Re: [coreboot] Powersavings: 8W of difference between bios and coreboot

[Felix Held]

Hi!
> BIOS: 11W Coreboot: 19W [...]

Can you also measure the power consumption with the GPU enabled under 
the vendor firmware?
> and no, the NVidia GPU was not enabled in corebooy. Both results were 
> on integrated GPU only

Have you only disabled the nVidia GPU in devicetree.cb (that will only 
disable the PCIe interface on the CPU side) or have you also disabled 
the GPU power supply via the GFXCORE_ON_D signal? Since that signal is 
driven by the power management companion chip (Thinker-1), you probably 
have to talk to the EC to do that.

Regards
Felix

Powersavings: 8W of difference between bios and coreboot

[Iru Cai]

Hi,

On Fri, Nov 18, 2016 at 4:43 PM, Felix Held 
wrote:
> Hi!
>
> BIOS: 11W Coreboot: 19W [...]
> >
>
> Can you also measure the power consumption with the GPU enabled under the
> vendor firmware?
>
> and no, the NVidia GPU was not enabled in corebooy. Both results were on
> > integrated GPU only
>
> Have you only disabled the nVidia GPU in devicetree.cb (that will only
> disable the PCIe interface on the CPU side) or have you also disabled the
> GPU power supply via the GFXCORE_ON_D signal? Since that signal is driven
> by the power management companion chip (Thinker-1), you probably have to
> talk to the EC to do that.

I don't know if Charlotte has added the ID of the dGPU to
src/drivers/lenovo/hybrid_graphics.c. Does the dGPU consume power after
hybrid_graphics.c disable the dGPU?

Regards
> Felix

Regards,
Iru