| Message ID | 94d99b261124b813adecf11e86a0ffe05c37f276.1490987945.git.leonard.crestez@nxp.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
Am Freitag, den 31.03.2017, 22:25 +0300 schrieb Leonard Crestez: > If the cpufreq driver tries to modify voltage/freq during suspend/resume > it might need to control an external PMIC via I2C or SPI but those > devices might be already suspended. > > To avoid this scenario we just increase cpufreq to highest setpoint > before suspend. This issue can easily be triggered by ldo-bypass but in > theory any regulator set_voltage call can end up having to modify > external supply voltages. > > Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > drivers/cpufreq/imx6q-cpufreq.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c > index be90ee3..e2c1fbf 100644 > --- a/drivers/cpufreq/imx6q-cpufreq.c > +++ b/drivers/cpufreq/imx6q-cpufreq.c > @@ -162,6 +162,7 @@ static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) > static int imx6q_cpufreq_init(struct cpufreq_policy *policy) > { > policy->clk = arm_clk; > + policy->suspend_freq = freq_table[soc_opp_count - 1].frequency; I think soc_opp_count includes all OPPs from the DT, some of which might be disabled based on the fuse settings of the SoC. So this should probably not switch to the highest OPP unconditionally, but rather switch to the highest _enabled_ OPP. Regards, Lucas > return cpufreq_generic_init(policy, freq_table, transition_latency); > } > > @@ -173,6 +174,7 @@ static struct cpufreq_driver imx6q_cpufreq_driver = { > .init = imx6q_cpufreq_init, > .name = "imx6q-cpufreq", > .attr = cpufreq_generic_attr, > + .suspend = cpufreq_generic_suspend, > }; > > static int imx6q_cpufreq_probe(struct platform_device *pdev)
On Tue, 2017-04-04 at 11:51 +0200, Lucas Stach wrote: > Am Freitag, den 31.03.2017, 22:25 +0300 schrieb Leonard Crestez: > > > > If the cpufreq driver tries to modify voltage/freq during suspend/resume > > it might need to control an external PMIC via I2C or SPI but those > > devices might be already suspended. > > > > To avoid this scenario we just increase cpufreq to highest setpoint > > before suspend. This issue can easily be triggered by ldo-bypass but in > > theory any regulator set_voltage call can end up having to modify > > external supply voltages. > > > > Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > > --- > > drivers/cpufreq/imx6q-cpufreq.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c > > index be90ee3..e2c1fbf 100644 > > --- a/drivers/cpufreq/imx6q-cpufreq.c > > +++ b/drivers/cpufreq/imx6q-cpufreq.c > > @@ -162,6 +162,7 @@ static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) > > static int imx6q_cpufreq_init(struct cpufreq_policy *policy) > > { > > policy->clk = arm_clk; > > + policy->suspend_freq = freq_table[soc_opp_count - 1].frequency; > I think soc_opp_count includes all OPPs from the DT, some of which might > be disabled based on the fuse settings of the SoC. So this should > probably not switch to the highest OPP unconditionally, but rather > switch to the highest _enabled_ OPP. You're right, this does not appear to be correct. Looking at soc_opp_count it should probably be a local variable in the code initializing imx6_soc_volt. And the imx6_soc_volt array itself could now be replaced with opp's support for multiple supply voltages. I'll post v2.
diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c index be90ee3..e2c1fbf 100644 --- a/drivers/cpufreq/imx6q-cpufreq.c +++ b/drivers/cpufreq/imx6q-cpufreq.c @@ -162,6 +162,7 @@ static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index) static int imx6q_cpufreq_init(struct cpufreq_policy *policy) { policy->clk = arm_clk; + policy->suspend_freq = freq_table[soc_opp_count - 1].frequency; return cpufreq_generic_init(policy, freq_table, transition_latency); } @@ -173,6 +174,7 @@ static struct cpufreq_driver imx6q_cpufreq_driver = { .init = imx6q_cpufreq_init, .name = "imx6q-cpufreq", .attr = cpufreq_generic_attr, + .suspend = cpufreq_generic_suspend, }; static int imx6q_cpufreq_probe(struct platform_device *pdev)