How to handle GPIO differences between P8 and P9

[Xo Wang]

On Mon, Nov 7, 2016 at 9:01 AM, Mine <mine260309 at gmail.com> wrote:
> On Mon, Nov 7, 2016 at 10:19 AM, Patrick Williams <patrick at stwcx.xyz> wrote:
>> On Mon, Nov 07, 2016 at 05:10:59PM +0800, Yi TZ Li wrote:
>>> I committed a patch: https://gerrit.openbmc-project.xyz/#/c/1019/
>>> to add a getSystemName() dbus method in org.obmc.managers.System interface.
>>> There are several places in skeleton requires fix for a specific system.
>>>
>>> Other way be add a compile flag in yocto when building Skeleton.
>>
>> We are really trying to avoid "if (machine_type == ...)" type code.  This
>> becomes a gigantic problem when we are talking about supporting 3 dozen
>> machines.
>>
>> --
>> Patrick Williams
>
> Yup, I prefer not to write `if (machine_type == ...)` type code, nor
> to have a compile flag (it just becomes `#if xxx` or `#ifdef xxx`).
>
> The temp fix by not defining `IDBTN` will not only cause error log,
> but also prevent the code in `op-hostctl/control_host_obj.c` to work,
> because it will get error during opening the GPIO, and jump out,
> resulting in error: "GPIO sequence failed".
>
> If we are targeting for booting P9 up, I would suggest a temp fix by
> defining `IDBTN` for both Witherspoon and Romulus.
> It will not block power on, but may break a function related to LED.
>
> --
> BRs,
> Lei YU
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> openbmc at lists.ozlabs.org
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We had a similar issue in the op-pwrctl where the source hard-coded
the system net names. There I put in a short-term solution of adding a
function-specific abstraction over the net names into the System.py
config, removing the per-machine patches for name and polarity:
https://gerrit.openbmc-project.xyz/#/c/606/
https://gerrit.openbmc-project.xyz/#/c/689/

It's not difficult to extend POWER_CONFIG for GPIO functions that only
exist on one machine, like so:
https://gerrit.openbmc-project.xyz/#/c/608/3

With the abstraction taking place in the Python machine config, we
don't need per-machine dispatch in the user interface (op-pwrctl,
op-hostctl, op-pwr-button, etc).

Does that work for you in the short term?

cheers
xo