Re: [PATCH 4/4] hwmon: (occ) Add soft minimum power cap attribute

[Eddie James <eajames@linux.ibm.com>]

On 2/16/22 00:33, Joel Stanley wrote:
> On Tue, 15 Feb 2022 at 15:11, Eddie James <eajames@linux.ibm.com> wrote:
>> Export the power caps data for the soft minimum power cap through hwmon.
>>
>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
>> ---
>>   drivers/hwmon/occ/common.c | 19 ++++++++++++++++---
>>   1 file changed, 16 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
>> index 0cb4a0a6cbc1..f00cd59f1d19 100644
>> --- a/drivers/hwmon/occ/common.c
>> +++ b/drivers/hwmon/occ/common.c
>> @@ -674,6 +674,9 @@ static ssize_t occ_show_caps_3(struct device *dev,
>>          case 7:
>>                  val = caps->user_source;
>>                  break;
>> +       case 8:
>> +               val = get_unaligned_be16(&caps->soft_min) * 1000000ULL;
>> +               break;
>>          default:
>>                  return -EINVAL;
>>          }
>> @@ -835,12 +838,13 @@ static int occ_setup_sensor_attrs(struct occ *occ)
>>          case 1:
>>                  num_attrs += (sensors->caps.num_sensors * 7);
>>                  break;
>> -       case 3:
>> -               show_caps = occ_show_caps_3;
>> -               fallthrough;
>>          case 2:
>>                  num_attrs += (sensors->caps.num_sensors * 8);
>>                  break;
>> +       case 3:
>> +               show_caps = occ_show_caps_3;
>> +               num_attrs += (sensors->caps.num_sensors * 9);
> How do we know this changed from 8 to 9?


Well we made the structure change a while back when adding P10 support, 
but didn't bother to export the "soft min" field. Now it's needed.


>
> We should start adding links to the occ source code, or a similar
> reference, when making these changes so they can be reviewed.


I would but it doesn't appear to be public for P10 yet... at least, no 
one has updated the P9 OCC spec hosted in the open-power repo: 
https://github.com/open-power/docs


Thanks,

Eddie


>
>> +               break;
>>          default:
>>                  sensors->caps.num_sensors = 0;
>>          }
>> @@ -1047,6 +1051,15 @@ static int occ_setup_sensor_attrs(struct occ *occ)
>>                          attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
>>                                                       show_caps, NULL, 7, 0);
>>                          attr++;
>> +
>> +                       if (sensors->caps.version > 2) {
>> +                               snprintf(attr->name, sizeof(attr->name),
>> +                                        "power%d_cap_min_soft", s);
>> +                               attr->sensor = OCC_INIT_ATTR(attr->name, 0444,
>> +                                                            show_caps, NULL,
>> +                                                            8, 0);
>> +                               attr++;
>> +                       }
>>                  }
>>          }
>>
>> --
>> 2.27.0
>>