On Wed, Dec 7, 2016 at 11:31 AM, Viresh Kumar viresh.kumar@linaro.org wrote:
This reverts commit ef3caabee9691386e6801ea92150e37277db9c7a.
The commit was based on the assumption that a platform with voltages specified with individual OPPs, would have registered a regulator as well in order to do full DVFS.
That assumption is broken by the Tegra124 platform.
For Tegra124, the voltage is not scaled via a direct call to the regulator subsystem because the DFLL directly controls the I2C interface that controls the voltage. The DFLL essentially figures out the max frequency for a given voltage. So to run at a particular frequency, the DFLL continuously adjusts the voltage in a control loop fashion to get the desired frequency.
Following are the logs from: NVIDIA Tegra124 Jetson TK1
cpufreq: cpufreq_online: CPU0: Running at unlisted freq: 696000 KHz cpu cpu0: dev_pm_opp_set_rate: Regulator not registered with OPP core cpufreq: __target_index: Failed to change cpu frequency: -22 ------------[ cut here ]------------ kernel BUG at drivers/cpufreq/cpufreq.c:1235!
Fix these by reverting the offending commit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Rafael, you can simply drop the patch if that is easier for you.
Done.
Thanks, Rafael