| Message ID | 20220224081131.27282-5-lukasz.luba@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | viresh kumar |
| Headers | show |
| Series | Introduce "opp-microwatt" and 'advanced' Energy Model from DT | expand |
On 24-02-22, 08:11, Lukasz Luba wrote: > The new registration method allows to get power values from the DT OPP > definition. The new OPP entry property "opp-microwatt" contains total > power expressed in micro-Watts. Align the EM documentation with this > new possible registration method of 'advanced' EM. > > Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> > --- > Documentation/power/energy-model.rst | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/Documentation/power/energy-model.rst b/Documentation/power/energy-model.rst > index 5ac62a7b4b7c..719253fd5215 100644 > --- a/Documentation/power/energy-model.rst > +++ b/Documentation/power/energy-model.rst > @@ -113,6 +113,16 @@ to: return warning/error, stop working or panic. > See Section 3. for an example of driver implementing this > callback, or Section 2.4 for further documentation on this API > > +Registration of 'advanced' EM using DT I am not really sure if this should be called *Advanced*. Just call it registration of EM using DT. > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + > +The 'advanced' EM can also be registered using OPP framework and information > +in DT "operating-points-v2". Each OPP entry in DT can be extended with a > +property "opp-microwatt" containing micro-Watts power value. This OPP DT > +property allows a platform to register EM power values which are reflecting > +total power (static + dynamic). These power values might be coming directly > +from experiments and measurements. > + > Registration of 'simple' EM > ~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > -- > 2.17.1
On 2/24/22 09:15, Viresh Kumar wrote: > On 24-02-22, 08:11, Lukasz Luba wrote: >> The new registration method allows to get power values from the DT OPP >> definition. The new OPP entry property "opp-microwatt" contains total >> power expressed in micro-Watts. Align the EM documentation with this >> new possible registration method of 'advanced' EM. >> >> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> >> --- >> Documentation/power/energy-model.rst | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/Documentation/power/energy-model.rst b/Documentation/power/energy-model.rst >> index 5ac62a7b4b7c..719253fd5215 100644 >> --- a/Documentation/power/energy-model.rst >> +++ b/Documentation/power/energy-model.rst >> @@ -113,6 +113,16 @@ to: return warning/error, stop working or panic. >> See Section 3. for an example of driver implementing this >> callback, or Section 2.4 for further documentation on this API >> >> +Registration of 'advanced' EM using DT > > I am not really sure if this should be called *Advanced*. Just call it > registration of EM using DT. Our partners had a lot of issues with EM+EAS, because they were not aware of the internals of EM and limitations. We've started to name two types of EM: 'advanced' and 'simple'. The 'simple' is the one which causes issues. Now when we contact with partners we ask if they use 'simple' EM and see some issues in EAS. This is a needed clarification and naming convention that we use. Here the paragraph name is stressing the fact explicitly that from today we have the option to provide real power measurements using DT and it will be the 'advanced' EM.
On 24-02-22, 09:25, Lukasz Luba wrote: > Our partners had a lot of issues with EM+EAS, because they were not > aware of the internals of EM and limitations. > > We've started to name two types of EM: 'advanced' and 'simple'. > The 'simple' is the one which causes issues. Now when we contact with > partners we ask if they use 'simple' EM and see some issues in EAS. > This is a needed clarification and naming convention that we use. > > Here the paragraph name is stressing the fact explicitly that > from today we have the option to provide real power measurements using > DT and it will be the 'advanced' EM. I understand the background now, and since I am part of the same community I can appreciate that. But being a maintainer, I have to say that when we look at something from Upstream's point of view, we may have to neglect/ignore the terminology used in downstream. From what I can see, there is no advancement here, as of now. This is a very small change where we are getting pre-evaluated power values from DT, instead of calculating them at runtime. The data may be more correct, but the EM doesn't get advanced because of that. And so using such terminology is only going to harm further. If EM gets a "advanced" algorithm later on, which can improve things, then yes we can call it advanced, but for now there is nothing.
On 2/24/22 09:37, Viresh Kumar wrote: > On 24-02-22, 09:25, Lukasz Luba wrote: >> Our partners had a lot of issues with EM+EAS, because they were not >> aware of the internals of EM and limitations. >> >> We've started to name two types of EM: 'advanced' and 'simple'. >> The 'simple' is the one which causes issues. Now when we contact with >> partners we ask if they use 'simple' EM and see some issues in EAS. >> This is a needed clarification and naming convention that we use. >> >> Here the paragraph name is stressing the fact explicitly that >> from today we have the option to provide real power measurements using >> DT and it will be the 'advanced' EM. > > I understand the background now, and since I am part of the same > community I can appreciate that. But being a maintainer, I have to say > that when we look at something from Upstream's point of view, we may > have to neglect/ignore the terminology used in downstream. I understand your upstream point of view. > > From what I can see, there is no advancement here, as of now. This is > a very small change where we are getting pre-evaluated power values > from DT, instead of calculating them at runtime. The data may be more > correct, but the EM doesn't get advanced because of that. And so using > such terminology is only going to harm further. If EM gets a > "advanced" algorithm later on, which can improve things, then yes we > can call it advanced, but for now there is nothing. > Fair enough, I'll drop this word from the paragraph name.
diff --git a/Documentation/power/energy-model.rst b/Documentation/power/energy-model.rst index 5ac62a7b4b7c..719253fd5215 100644 --- a/Documentation/power/energy-model.rst +++ b/Documentation/power/energy-model.rst @@ -113,6 +113,16 @@ to: return warning/error, stop working or panic. See Section 3. for an example of driver implementing this callback, or Section 2.4 for further documentation on this API +Registration of 'advanced' EM using DT +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The 'advanced' EM can also be registered using OPP framework and information +in DT "operating-points-v2". Each OPP entry in DT can be extended with a +property "opp-microwatt" containing micro-Watts power value. This OPP DT +property allows a platform to register EM power values which are reflecting +total power (static + dynamic). These power values might be coming directly +from experiments and measurements. + Registration of 'simple' EM ~~~~~~~~~~~~~~~~~~~~~~~~~~~
The new registration method allows to get power values from the DT OPP definition. The new OPP entry property "opp-microwatt" contains total power expressed in micro-Watts. Align the EM documentation with this new possible registration method of 'advanced' EM. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> --- Documentation/power/energy-model.rst | 10 ++++++++++ 1 file changed, 10 insertions(+)