| Message ID | 20240619140849.368580-1-ulf.hansson@linaro.org |
|---|---|
| Headers | show |
| Series | OPP/pmdomain: Assign required_devs for required OPPs through genpd | expand |
On 19.06.2024 4:08 PM, Ulf Hansson wrote: > 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. So, is this series essentially tackling a problem like this: pdp_A: power-domain-provider@aaaaaa { [...] opp-table { pdp_A_opp0: opp-0 { opp-level = <0>; }; }; }; pdp_B: power-domain-provider@bbbbbbb { [...] opp-table { pdp_B_opp0: opp-0 { opp-level = <0>; }; }; }; nice-device@ccccccc { [...] power-domains = <&pdp_A>, <&pdp_B>; // order doesn't match /\ required-opps = <&pdp_B_opp0>, <&pdp_A_opp0>; }; ? Konrad
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(-)