Re: [PATCH v4 3/8] scsi: ufs: ufs-mediatek: Remove useless mediatek,ufs-boost-crypt property

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 16/04/24 12:31, Peter Wang (王信友) ha scritto:
> 
>> Yes this causes -> less than half of a millisecond <- of additional
>> boot time
>> if the dvfsrc-supply is present but boost-microvolt is not.
>>
>> I really don't see the problem with that :-)
>>
> 
> Adding a little bit of boot time to one smartphone might not be a
> problem, but when you consider a billion smartphones each adding a
> little bit, the cumulative effect becomes significant. The power
> consumption of these accumulated times will continue to increase,
> contributing to the Earth's carbon emissions. Moreover, removing the
> master switch for this feature doesn't seem to have any benefits other
> than not having to set it in the DTS. Similarly, the master switch for
> VA09 seems to have more disadvantage.
> 

Sorry, but I still don't see how a few *microseconds* more of boot time can
be significant, even related to power consumption during boot.

If that was a few milliseconds, then I'd agree with you, but that's not the case.

Removing the master switch has a benefit: you *lose* a few microseconds of boot
time (so, boots in *few microseconds LESS*) on platforms that would have this set
in devicetree, as this property is redundant with the other activation checks
for those features.

So, there you go: if the majority of MediaTek platforms are already using this
crypt boost feature, then this commit reduces carbon emissions, as those would
boot in a few less microseconds.

Regards,
Angelo

> 
>> Regards,
>> Angelo
>>
>>> Thanks.
>>> Peter
>>>
>>>
>>>
>>>>    	ret = ufs_mtk_init_va09_pwr_ctrl(hba);
>>>>    	if (ret)
>>
>>