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Hi Gabi,

I have checked, its working, can you follow these steps?

// change DSP clock rate

rrate = 990000000;
clk = clk_get(NULL, "gem_ick");
ret = clk_set_rate(clk, rrate);

if (ret)

pr_err("Failed to set the requested rate %lu and dsp running at %lu", rrate, clk_get_rate(clk));

Recent kernel versions clk_enable(clk); is required to change the rate, and not required in your case.

Regards

AnilKumar

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Anil

We can chagne the DSP frequency in u-boot (code),

How is the DSP clock set in u-boot?  The referenced document says nothing about this.

By the way, I have located the clock settings in u-boot for the ARM.

Lee

Hi Lee,

Better go throgh the TRM of DM8168 for pll configuration. section "1.10.3 Flying Adder PLL"

Regards

AnilKumar

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Hi Lee,

MAIN_*1 (u-boot, evm.c, main_pll_init_ti816x) macros are coresponding to DSP clock out rate values, change to required values. Make sure that you are not exceeding the limits.

Regards

AnilKumar

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Hi Anil,

Anil

// change DSP clock rate

rrate = 990000000;
clk = clk_get(NULL, "gem_ick");
ret = clk_set_rate(clk, rrate);

if (ret)

pr_err("Failed to set the requested rate %lu and dsp running at %lu", rrate, clk_get_rate(clk));

I have done what you have written above, i saw no error, but the clock frequency doesn't change, i am working with an OMX application could it be that some where else the clock frequency is set back to 800MHz?

Thanks,
Gabi 

Hi Gabi,

I am not aware of OMX application, Can you print the rate after setting to new value? We can conclude at this position setrate on your setup is working/not.

Another option is you can write some kernel module application, after kernel boots up you can control the clock rate using some sysfs/debugfs entries.

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!