[U-Boot] CPU Clock frequency at boot time - Nvidia Jetson TK1

[vinoth eswaran]

Hello Developers,

  Currently I am working on an embedded project using Tegra Jetson Tk1
board. The Linux Kernel version is 4.7 and the u-boot version is v2016.05.
I am building a customised Linux kernel and u-boot to have the fastest boot
time possible.

During Kernel startup I am seeing some error messages related to CPU clock
frequencies like,

[    0.000000] Tegra clk 127: register failed with -17

[    4.275805] cpufreq: cpufreq_online: CPU0: Running at unlisted freq:
696000 KHz
[    4.275845] cpufreq: cpufreq_online: CPU0: Unlisted initial frequency
changed to: 714000 KHz

On seeing the bootchart I have a feeling that the cpu clock frequency might
be low - as lot of drivers are taking more time than usual, so I now wish
to know what frequency does the cpu cores are running on during boot time.
I am not clear on who is responsible(u-boot/kernel) for setting up the cpu
clock frequency during the boot time.

In u-boot which modules do I need to look to get information about cpu
frequency being set.

Thanks & Regards,
Vinothkumar