Re: [PATCH v2 6/6] arm64: dts: mediatek: mt8390-genio-700-evk: Enable Mali GPU

[AngeloGioacchino Del Regno]

Il 27/09/24 12:30, Pablo Sun ha scritto:
> Configure GPU regulator supplies and enable GPU for GENIO 700 EVK.
>
> The GPU in MT8390 & MT8188 has two power inputs: "DVDD_GPU" and
> "DVDD_SRAM_GPU". In Genio 700 EVK, DVDD_GPU is supplied by
> mt6359_vproc2_buck_reg, and DVDD_SRAM_GPU is supplied by
> mt6359_vsram_others_ldo_reg.
>
> According to section 5.2 "Recommended Operating Conditions" in
> MT8390 IoT Application Processor Datasheet v1.9, The recommended
> operating voltage ranges are:
>
> - DVDD_GPU: min 0.55V, max 0.86V, typical 0.75V
> - DVDD_SRAM_GPU: min 0.71V, max 0.92V, typical 0.85V
>
> To further optimize power saving, we couple DVDD_SRAM_GPU to
> DVDD_GPU according to the following relation:
>
> - For opp-880000000 or lower frequency, keep 0.75V
> - For opp-915000000 and higher, DVDD_SRAM_GPU should follow
>    DVDD_GPU. The exact voltage for DVDD_GPU should be decided by
>    speed binning.
>
> This rule is derived from the OPP table in the link.
>
> In addition, set the voltage spread to 6250 uV, the step size of
> 'ldo_vsram_others' regulator of mt6359, otherwise the regulator
> set_voltage operation fails.
>
> Link: https://gitlab.com/mediatek/aiot/rity/meta-mediatek-bsp/-/blob/eedd6aedd4b0cfc0ee79b9c9b9650dfa73cf87f6/recipes-kernel/dtbo/mt8390/gpu-mali.dts
> Signed-off-by: Pablo Sun <pablo.sun@xxxxxxxxxxxx>
> Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>