[PATCH 0/7] OPP/pmdomain: Assign required_devs for required OPPs through genpd

[Ulf Hansson]

Through dev_pm_opp_set_config() the _opp_attach_genpd() allows consumer
drivers to hook up a device to its PM domains. This works for both a single
and multiple PM domains. Their corresponding virtual devices that are
created by genpd during attach, are later being assigned as the
required_devs for the corresponding required OPPs.

In principle this works fine, but there are some problems. Especially as
the index for a "required-opps" may not necessarily need to match the index
for the "power-domain" in DT, in which case things gets screwed up.

This series intends to improve the situation, but it's also the first step to
enable consumers of _opp_attach_genpd() to start migrating to use the new
dev_pm_domain_attach_list() instead. Down the road, we should then be able to
drop _opp_attach_genpd() completely.

To test this, I have used a QEMU setup, with local PM test-drivers to try to
test all various combinations of single/multi power/performance PM domains for
a device. Hopefully I have covered it all, but I would certainly appreciate if
someone could help to run a slew of tests on some HWs.

Note: Patch1 is actually a fix that has been posted [1] separately too. I
decided to include here for completeness.

Kind regards
Ulf Hansson

[1]
https://lore.kernel.org/linux-kernel/20240618155013.323322-1-ulf.hansson@linaro.org/

Ulf Hansson (7):
  OPP: Fix support for required OPPs for multiple PM domains
  OPP: Drop a redundant in-parameter to _set_opp_level()
  OPP: Rework _set_required_devs() to manage a single device per call
  OPP: Introduce an OF helper function to inform if required-opps is
    used
  pmdomain: core: Manage the default required OPP from a separate
    function
  OPP/pmdomain: Set the required_dev for a required OPP during genpd
    attach
  pmdomain: core: Drop the redundant dev_to_genpd_dev()

 drivers/opp/core.c        | 185 ++++++++++++++++++--------------------
 drivers/opp/of.c          |  32 +++++++
 drivers/opp/opp.h         |   4 +-
 drivers/pmdomain/core.c   | 103 ++++++++++++++++-----
 include/linux/pm_domain.h |   6 --
 include/linux/pm_opp.h    |  16 +++-
 6 files changed, 215 insertions(+), 131 deletions(-)

-- 
2.34.1