Re: [PATCH v5 09/10] phy: qualcomm: phy-qcom-qmp-ufs: Add High Speed Gear 5 support for SM8550

Can Guo
2023-11-28T10:04:35Z

Hi Neil,

On 11/28/2023 5:59 PM, neil.armstrong@linaro.org wrote:
> Hi,
>
> On 23/11/2023 09:46, Can Guo wrote:
>> On SM8550, two sets of UFS PHY settings are provided, one set is to
>> support
>> HS-G5, another set is to support HS-G4 and lower gears. The two sets
>> of PHY
>> settings are programming different values to different registers, mixing
>> the two sets and/or overwriting one set with another set is definitely
>> not
>> blessed by UFS PHY designers.
>>
>> To add HS-G5 support for SM8550, split the two sets of PHY settings into
>> their dedicated overlay tables, only the common parts of the two sets of
>> PHY settings are left in the .tbls.
>>
>> Consider we are going to add even higher gear support in future, to avoid
>> adding more tables with different names, rename the .tbls_hs_g4 and
>> make it
>> an array, a size of 2 is enough as of now.
>>
>> In this case, .tbls alone is not a complete set of PHY settings, so
>> either
>> tbls_hs_overlay[0] or tbls_hs_overlay[1] must be applied on top of the
>> .tbls to become a complete set of PHY settings.
>>
>> Signed-off-by: Can Guo <quic_cang@quicinc.com>
>
> Since Vinod has already merged SM8650 UFS PHY support, I'm afraid this
> serie will break UFS if the SM8650 UFS tables aren't updated aswell.
>
> Could you confirm if this will be the case ?

Because this change modifies data struct, it would be caught during
compiliation stage even if this change applies cleanly, hence it won't
break UFS.

Thanks,
Can Guo.

>
> Thanks,
> Neil
>
>