On 26-08-20, 11:33, Stephan Gerhold wrote: > dev_pm_opp_attach_genpd() allows attaching an arbitrary number of > power domains to an OPP table. In that case, the genpd core will > create a virtual device for each of the power domains. > > At the moment, the OPP core only calls > dev_pm_genpd_set_performance_state() on these virtual devices. > It does not attempt to power on the power domains. Therefore > the required power domain might never get turned on. > > So far, dev_pm_opp_attach_genpd() is only used in qcom-cpufreq-nvmem.c > to attach the CPR power domain to the CPU OPP table. The CPR driver > does not check if it was actually powered on so this did not cause > any problems. However, other drivers (e.g. rpmpd) might ignore the > performance state until the power domain is actually powered on. > > Since these virtual devices are managed exclusively by the OPP core, > I would say that it should also be responsible to ensure they are > enabled. > > This commit implements this similar to the non-virtual power domains; > we create device links for each of attached power domains so that they > are turned on whenever the consumer device is active. > > Signed-off-by: Stephan Gerhold <[email protected]> > ---
Applied with some changes, hope that is fine: Signed-off-by: Stephan Gerhold <[email protected]> [ Viresh: Rearranged the code to remove extra loop and minor cleanup ] Signed-off-by: Viresh Kumar <[email protected]> --- drivers/opp/core.c | 37 ++++++++++++++++++++++++++++++++++++- drivers/opp/opp.h | 1 + 2 files changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/opp/core.c b/drivers/opp/core.c index e65174725a4d..b608b0253079 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -17,6 +17,7 @@ #include <linux/device.h> #include <linux/export.h> #include <linux/pm_domain.h> +#include <linux/pm_runtime.h> #include <linux/regulator/consumer.h> #include "opp.h" @@ -1967,10 +1968,15 @@ static void _opp_detach_genpd(struct opp_table *opp_table) if (!opp_table->genpd_virt_devs[index]) continue; + if (opp_table->genpd_virt_links[index]) + device_link_del(opp_table->genpd_virt_links[index]); + dev_pm_domain_detach(opp_table->genpd_virt_devs[index], false); opp_table->genpd_virt_devs[index] = NULL; } + kfree(opp_table->genpd_virt_links); + opp_table->genpd_virt_links = NULL; kfree(opp_table->genpd_virt_devs); opp_table->genpd_virt_devs = NULL; } @@ -2002,8 +2008,10 @@ struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, { struct opp_table *opp_table; struct device *virt_dev; + struct device_link *dev_link; int index = 0, ret = -EINVAL; const char **name = names; + u32 flags; opp_table = dev_pm_opp_get_opp_table(dev); if (IS_ERR(opp_table)) @@ -2030,6 +2038,21 @@ struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, if (!opp_table->genpd_virt_devs) goto unlock; + opp_table->genpd_virt_links = kcalloc(opp_table->required_opp_count, + sizeof(*opp_table->genpd_virt_links), + GFP_KERNEL); + if (!opp_table->genpd_virt_links) { + kfree(opp_table->genpd_virt_devs); + opp_table->genpd_virt_devs = NULL; + goto unlock; + } + + /* Turn on power domain initially if consumer is active */ + pm_runtime_get_noresume(dev); + flags = DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS; + if (pm_runtime_active(dev)) + flags |= DL_FLAG_RPM_ACTIVE; + while (*name) { if (index >= opp_table->required_opp_count) { dev_err(dev, "Index can't be greater than required-opp-count - 1, %s (%d : %d)\n", @@ -2043,12 +2066,23 @@ struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, dev_err(dev, "Couldn't attach to pm_domain: %d\n", ret); goto err; } - opp_table->genpd_virt_devs[index] = virt_dev; + + /* Create device links to manage runtime PM */ + dev_link = device_link_add(dev, opp_table->genpd_virt_devs[index], + flags); + if (!dev_link) { + dev_err(dev, "Failed to create device link\n"); + goto err; + } + opp_table->genpd_virt_links[index] = dev_link; + index++; name++; } + pm_runtime_put(dev); + if (virt_devs) *virt_devs = opp_table->genpd_virt_devs; mutex_unlock(&opp_table->genpd_virt_dev_lock); @@ -2056,6 +2090,7 @@ struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, return opp_table; err: + pm_runtime_put(dev); _opp_detach_genpd(opp_table); unlock: mutex_unlock(&opp_table->genpd_virt_dev_lock); diff --git a/drivers/opp/opp.h b/drivers/opp/opp.h index 78e876ec803e..be5526cdbdba 100644 --- a/drivers/opp/opp.h +++ b/drivers/opp/opp.h @@ -186,6 +186,7 @@ struct opp_table { struct mutex genpd_virt_dev_lock; struct device **genpd_virt_devs; + struct device_link **genpd_virt_links; struct opp_table **required_opp_tables; unsigned int required_opp_count;
