Re: [RFC PATCH 00/13] Add tuning algorithm for delay chain

From: Raghavendra, Vignesh
Date: Wed Jan 31 2024 - 08:53:40 EST




On 1/31/2024 7:11 PM, Krzysztof Kozlowski wrote:
> On 31/01/2024 14:35, Raghavendra, Vignesh wrote:
>>> Judith Mendez (11):
>>> drivers: mmc: host: sdhci_am654: Add tuning algorithm for delay chain
>>> drivers: mmc: host: sdhci_am654: Write ITAPDLY for DDR52 timing
>>> drivers: mmc: host: sdhci_am654: Add missing OTAP/ITAP enable
>>> drivers: mmc: host: sdhci_am654: Add ITAPDLYSEL in
>>> sdhci_j721e_4bit_set_clock
>>> drivers: mmc: host: sdhci_am654: Fix ITAPDLY for HS400 timing
>>
>> These patches needs to have Fixes: tag as they are bug fixes IMO.
>>
>>> arm64: dts: ti: k3-am62a-main: Add sdhci2 instance
>>> arm64: dts: ti: k3-am64-main: Update ITAP/OTAP values for MMC
>>> arm64: dts: ti: k3-am62-main: Update ITAP/OTAP values for MMC
>>> arm64: dts: ti: k3-am62p: Add missing properties for MMC
>>> arm64: dts: ti: k3-am6*: Remove DLL properties for soft phys
>>> arm64: dts: ti: k3-am6*: Reorganize MMC properties
>>>
>>> Nitin Yadav (2):
>>> arm64: dts: ti: k3-am62a-main: Add sdhci0 instance
>>> arm64: dts: ti: k3-am62a7-sk: Enable eMMC support
>>>
>>
>> Can the driver changes be merged independent of DT changes? Or are they
>> meant to go together? Latter would be problematic as it creates cross
>> tree dependencies.
>
> DTS cannot depend on driver changes, because that would mean hardware
> description is not really hardware but OS. So the answer to your
> question must be "yes, can be merged independently".
>

Normally yes, but here I see update to tuning algorithm and timing
paramaters to the algorithm. DT updates seem to be nature of bug fixes
where in parameters have been refined due to more HW char
data/understanding being available.

I get nervous when anyone posts both driver and DT changes in a single
series, because they may not have tested driver changes standalone and
may have broken the DT backward compatibility

> Best regards,
> Krzysztof
>

Regards
Vignesh