Available EMC frequencies for Nano

Hello, I am using a nano booted with the sd card image. I am trying to change the EMC frequency using the commands

$ echo <emc_freq> > /sys/kernel/debug/clk/override.emc/clk_update_rate

$ echo 1 > /sys/kernel/debug/clk/override.emc/clk_state

However i am only able to change the frequency from the min frequency (204000000) to the max (1600000000) and vice versa. Are there any frequencies in this range that I can also use? I am verifying the results using jetson_clocks --show.

for Nano , you can see the supported freq in the /sys/kernel/debug/clk/emc/possible_rates
I think only 2 freq are supported. [tegra210-porg-p3448-emc-a00.dtsi]
while TX1 will have many supported

it appears to me that /sys/kernel/debug/clk/emc/possible_rates does not exist.

root@nano0:~# cd /sys/kernel/debug/clk/emc
root@nano0:/sys/kernel/debug/clk/emc# ls
clk_accuracy      clk_flags           clk_parent  clk_possible_parents  clk_rate   clk_update_rate  frequency_stats_table  pto_rate
clk_enable_count  clk_notifier_count  clk_phase   clk_prepare_count     clk_state  dvfs_freq_offs   pto_cycles

i am not sure what tegra210-porg-p3448-emc-a00.dtsi is referring to, where can i take a look at it?

Also, is the number of supported EMC frequencies something that can be changed by manually flashing L4T, rather than using the given sd card image?

Thanks

you can check frequency_stats_table .
Nano only supports two emc freq, 1600 is max value. In between is not allowed even if you flashed manually.
we share the kernel source and device tree files for the jetsons online. this file contains support emc freq for nano

https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/kernel_custom.html#wwpID0E0WD0HA

What is the need for more emc freq?

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