Re: [PATCH 0/2] MT8195 Cherry: Assign MFG vregs for power saving

From: Chen-Yu Tsai
Date: Tue Oct 31 2023 - 05:19:54 EST


On Mon, Oct 30, 2023 at 9:25 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
>
> This series assigns the right regulators to MFG0 and MFG1, respectively
> VGPU (GPU Core) and VSRAM_OTHERS (GPU SRAM), and removes the property
> regulator-always-on from both.
>
> This allows to save power both during runtime suspend and during system
> sleep; specifically because:
> 1. The GPU SRAM regulator is switched off during runtime suspend
> 2. The GPU Core regulator is switched off during system sleep
>
> Of course, in order for those power saving actions to actually take
> place, it is required to also have the code in [1].
> Anyway, even without series [1], this will not introduce any unstability
> as the Vgpu regulator will simply not ever get turned off.
>
> [1]: https://lore.kernel.org/r/20231030132257.85379-1-angelogioacchino.delregno@xxxxxxxxxxxxx
>
> AngeloGioacchino Del Regno (2):
> arm64: dts: mediatek: mt8195-cherry: Add MFG0 domain supply
> arm64: dts: mediatek: mt8195-cherry: Assign sram supply to MFG1 pd

Tested-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>

on Tomato without the power saving patches. Regulators are correctly
requested and I can see the SRAM regulator get turned on and off with
GPU usage.