Re: [PATCH v6 33/52] memory: tegra20: Support interconnect framework

From: Dmitry Osipenko
Date: Tue Oct 27 2020 - 16:25:38 EST


27.10.2020 13:09, Krzysztof Kozlowski пишет:
...
>> +err_msg:
>> + dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
>
> You will print such errors on all existing DTBs. Since it is not a
> failure of probe (it is actually quite expected, normal situation when
> booting with older DTB), let's change it to warning (here and in all
> other places and drivers).

The existing DTBs will be stopped on the error message below.

>> +
>> + return err;
>> +}
>> +
>> +static int tegra_emc_opp_table_init(struct tegra_emc *emc)
>> +{
>> + const char *rname = "core";
>> + int err;
>> +
>> + /*
>> + * Legacy device-trees don't have OPP table and EMC driver isn't
>> + * useful in this case.
>> + */
>> + if (!device_property_present(emc->dev, "operating-points-v2")) {
>> + dev_err(emc->dev, "OPP table not found\n");
>> + dev_err(emc->dev, "please update your device tree\n");
>> + return -ENODEV;
>> + }

The existing DTBs are stopped here.

...
>> + err = tegra_emc_opp_table_init(emc);
>> + if (err)
>> + goto unreg_notifier;
>
> This looks like the ABI break I mentioned around DT bindings. Are the
> bindings marked as unstable?

This T20 EMC driver wasn't ever used so far at all and this series makes
it useful. Hence I think it should be fine to assume that the T20 EMC
ABI is unstable.