This commit fixes a rare but possible case when the clk rate is updated
without update of the regulator voltage.
At boot up, CPUfreq checks if the system is running at the right freq. This
is a sanity check in case a bootloader set clk rate that is outside of freq
table present with cpufreq core. In such cases system can be unstable so
better to change it to a freq that is preset in freq-table.
The CPUfreq takes next freq that is >= policy->cur and this is our
target_freq that needs to be set now.
dev_pm_opp_set_rate(dev, target_freq) checks the target_freq and the
old_freq (a current rate). If these are equal it returns early. If not,
it searches for OPP (old_opp) that fits best to old_freq (not listed in
the table) and updates old_freq (!).
Here, we can end up with old_freq = old_opp.rate = target_freq, which
is not handled in _generic_set_opp_regulator(). It's supposed to update
voltage only when freq > old_freq || freq > old_freq.
if (freq > old_freq) {
ret = _set_opp_voltage(dev, reg, new_supply);
[...]
if (freq < old_freq) {
ret = _set_opp_voltage(dev, reg, new_supply);
if (ret)
It results in, no voltage update while clk rate is updated.
Example:
freq-table = {
1000MHz 1.15V
666MHZ 1.10V
333MHz 1.05V
}
boot-up-freq = 800MHz # not listed in freq-table
freq = target_freq = 1GHz
old_freq = 800Mhz
old_opp = _find_freq_ceil(opp_table, &old_freq); #(old_freq is modified!)
old_freq = 1GHz
Fixes: 6a0712f6f1 ("PM / OPP: Add dev_pm_opp_set_rate()")
Cc: 4.6+ <stable@vger.kernel.org> # v4.6+
Signed-off-by: Waldemar Rymarkiewicz <waldemar.rymarkiewicz@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
It should be fine to call dev_pm_opp_register_set_opp_helper() for all
possible CPUs, even if some of them share the OPP table as the caller
may not be aware of sharing policy.
Lets increment the reference count of the OPP table and return its
pointer. The caller need to call dev_pm_opp_register_put_opp_helper()
the same number of times later on to drop all the references.
To avoid adding another counter to count how many times
dev_pm_opp_register_set_opp_helper() is called for the same OPP table,
dev_pm_opp_register_put_opp_helper() frees the resources on the very
first call made to it, assuming that the caller would be calling it
sequentially for all the CPUs. We can revisit that if that assumption is
broken in the future.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
It should be fine to call dev_pm_opp_set_regulators() for all possible
CPUs, even if some of them share the OPP table as the caller may not be
aware of sharing policy.
Lets increment the reference count of the OPP table and return its
pointer. The caller need to call dev_pm_opp_put_regulators() the same
number of times later on to drop all the references.
To avoid adding another counter to count how many times
dev_pm_opp_set_regulators() is called for the same OPP table,
dev_pm_opp_put_regulators() frees the resources on the very first call
made to it, assuming that the caller would be calling it sequentially
for all the CPUs. We can revisit that if that assumption is broken in
the future.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
It should be fine to call dev_pm_opp_set_prop_name() for all possible
CPUs, even if some of them share the OPP table as the caller may not be
aware of sharing policy.
Lets increment the reference count of the OPP table and return its
pointer. The caller need to call dev_pm_opp_put_prop_name() the same
number of times later on to drop all the references.
To avoid adding another counter to count how many times
dev_pm_opp_set_prop_name() is called for the same OPP table,
dev_pm_opp_put_prop_name() frees the resources on the very first call
made to it, assuming that the caller would be calling it sequentially
for all the CPUs. We can revisit that if that assumption is broken in
the future.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
It should be fine to call dev_pm_opp_set_supported_hw() for all possible
CPUs, even if some of them share the OPP table as the caller may not be
aware of sharing policy.
Lets increment the reference count of the OPP table and return its
pointer. The caller need to call dev_pm_opp_put_supported_hw() the same
number of times later on to drop all the references.
To avoid adding another counter to count how many times
dev_pm_opp_set_supported_hw() is called for the same OPP table,
dev_pm_opp_put_supported_hw() frees the resources on the very first call
made to it, assuming that the caller would be calling it sequentially
for all the CPUs. We can revisit that if that assumption is broken in
the future.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The genpd core provides an API now to retrieve the performance state
from DT, use that instead of the ->get_pstate() callback.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
A device's DT node or its OPP nodes can contain a phandle to other
device's OPP node, in the "required-opps" property.
This patch implements a routine to find that required OPP from the node
that contains the "required-opps" property.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
"opp-hz" property is optional for power domains now and we shouldn't
error out if it is missing for power domains.
This patch creates two new routines, _get_opp_count() and
_opp_is_duplicate(), by separating existing code from their parent
functions. Also skip duplicate OPP check for power domain OPPs as they
may not have any the "opp-hz" field, but a platform specific performance
state binding to uniquely identify OPP nodes.
By default the debugfs OPP nodes are named using the "rate" value, but
that isn't possible for the power domain OPP nodes and hence they use
the index of the OPP node in the OPP node list instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
This adds the dev_pm_opp_{un}register_get_pstate_helper() helper
routines which will be used to set the get_pstate() callback for a
device. This callback will be later called internally by the OPP core to
get performance state corresponding to an OPP.
This is required temporarily until the time we have proper DT bindings
to include the performance state information.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The genpd framework now provides an API to request device's power
domain to update its performance state. Use that interface from the
OPP core for devices whose power domains support performance states.
Note that this commit doesn't add any mechanism by which performance
states are made available to the OPP core. That would be done by a
later commit.
Note that the current implementation is restricted to the case where
the device doesn't have separate regulators for itself. We shouldn't
over engineer the code before we have real use case for them. We can
always come back and add more code to support such cases later on.
Tested-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The routine is named incorrectly since the first attempt as there is
nothing like a put_opp() helper. We wanted to unregister the set_opp()
helper here and so it should rather be named as
dev_pm_opp_unregister_set_opp_helper().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On some i.MX6 platforms which do not have speed grading
check, opp table will not be created in platform code,
so cpufreq driver prints the following error message:
cpu cpu0: dev_pm_opp_get_opp_count: OPP table not found (-19)
However, this is not really an error in this case because the
imx6q-cpufreq driver first calls dev_pm_opp_get_opp_count()
and if it fails, it means that platform code does not provide
OPP and then dev_pm_opp_of_add_table() will be called.
In order to avoid such confusing error message, move it to
debug level.
It is up to the caller of dev_pm_opp_get_opp_count() to check its
return value and decide if it will print an error or not.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The drivers/base/power/ directory is special and contains code related
to power management core like system suspend/resume, hibernation, etc.
It was fine to keep the OPP code inside it when we had just one file for
it, but it is growing now and already has a directory for itself.
Lets move it directly under drivers/ directory, just like cpufreq and
cpuidle.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
