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

[AngeloGioacchino Del Regno]

Il 31/10/23 10:19, Chen-Yu Tsai ha scritto:
> On Mon, Oct 30, 2023 at 9:25 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno at collabora.com> 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@collabora.com
>>
>> 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 at chromium.org>
> 
> 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.

Yes, I confirm that the sram vreg going on/off is expected even without the power
saving patches (as the power domain refcount decreases during runtime suspend).

Thanks!

Angelo