Hi Dan,
Thanks for your feedback!
I've tested these patches with our platform, but have not tested with any
upstream platforms. I added tests for the OS-initiated mode code path in
TF-A-Tests [1] that we can run against upstream platforms to verify. I'm
not sure how I can get a hold of an upstream platform board; it'd be much
appreciated if perhaps maintainers of upstream platforms could help run the
tests?
In theory, any platform that supports CPU_SUSPEND would be able to support
both platform-coordinated mode and OS-initiated mode, since the power state
coordination happens either in the PSCI library implementation or in an
HLOS.
Wing
[1] https://review.trustedfirmware.org/c/TF-A/tf-a-tests/+/17684
On Fri, Nov 11, 2022 at 9:43 AM Okash Khawaja <okash(a)google.com> wrote:
> Hi Dan,
>
> The idea with OSI mode is that HLOS will have more awareness about
> power sequences and hence will be able to optimise power usage better
> (e.g. using heuristics) if it had more control. This means having HLOS
> which contains right modules for a specific platform and specific use
> case, if we want to do a power/perf comparison between OSI and
> plat-coordinated modes.
>
> On Fri, Nov 11, 2022 at 5:08 PM Dan Handley via TF-A
> <tf-a(a)lists.trustedfirmware.org> wrote:
> >
> > Hi Wing
> >
> > Thanks for your contribution. Are there any upstream platforms that
> these patches have been tested with? If so, it would be good to have
> visibility of the sw stack under test. Ideally, there would be at least 1
> platform that supported both platform-coordinated mode and OS-initiated
> mode, so that a fair power/performance comparison can be done.
> >
> >
> >
> > Regards
> >
> > Dan.
> >
> >
> >
> > From: Wing Li via TF-A <tf-a(a)lists.trustedfirmware.org>
> > Sent: 10 November 2022 05:53
> > To: tf-a(a)lists.trustedfirmware.org; tf-a-tests(a)lists.trustedfirmware.org
> > Subject: [TF-A] PSCI OS-initiated mode
> >
> >
> >
> > Hi,
> >
> > The PSCI specification defines two different power state coordination
> modes for CPU_SUSPEND that can be used to put a core or a group of cores
> into a low-power state. These modes are the platform-coordinated mode
> (default) and the OS-initiated mode (optional). OS-initiated mode is
> currently not supported by TF-A, while both modes are supported by the
> Linux Kernel.
> >
> > Requesting reviews for the patches [1] adding support for OS-initiated
> mode in TF-A and the corresponding tests in TF-A-Tests. Any feedback and
> comments are much appreciated.
> >
> > Thanks in advance!
> >
> > Wing
> >
> > [1] https://review.trustedfirmware.org/q/topic:psci-osi
> >
> > --
> > TF-A mailing list -- tf-a(a)lists.trustedfirmware.org
> > To unsubscribe send an email to tf-a-leave(a)lists.trustedfirmware.org
>
Hi,
The PSCI specification defines two different power state coordination modes
for CPU_SUSPEND that can be used to put a core or a group of cores into a
low-power state. These modes are the platform-coordinated mode (default)
and the OS-initiated mode (optional). OS-initiated mode is currently not
supported by TF-A, while both modes are supported by the Linux Kernel.
Requesting reviews for the patches [1] adding support for OS-initiated mode
in TF-A and the corresponding tests in TF-A-Tests. Any feedback and
comments are much appreciated.
Thanks in advance!
Wing
[1] https://review.trustedfirmware.org/q/topic:psci-osi
