Linux/AM5728: High precision interrupt

Hi,

At the moment I am not aware of any timer examples like what you are asking for kernel level modules. Typically TI supports SOC drivers and system latency application level questions. I will check on a possible suggestion to do what your asking. Could you describe the timer resolution you are looking for, you mentioned MHz? Could you also describe how the adjustments would be made? Would this run only in a kernel module?

Best Regards,
Schuyler

Hi,

I will try to clarify my needs.

I have a kernel module in which I have a function that must be invoked every 1ms, in hard real time accuracy, and the lowest jitter possible.
Furthermore, during runtime I need to make very fine adjustments to the interrupt frequency on the fly, making the interrupt cycle time a little bit longer or shorter.

In my x86 platform I invoke this function from the context of HPET ISR, after configuring the interrupt frequency to fire every 1ms, and I'm able to modify the load register of the timer on the fly, thus affecting the cycle time of the periodic interrupt.

I'm new to am5728, on which I'm trying to set up my system now.
If exists, a pointer to something that resembles the functionality I need would be great.
If not, a recommendation on a high precision event timer in the CPU and an example of use in the kernel would also be great.

Thanks a lot.

Hi,
Just an update, if you perform this command you can see the source clock for each timer using the pre-built images from the TI SDK.

cat /sys/kernel/debug/clk/clk_summary | grep timer

According to the TRM each timer can be selected with either 32KHz or the system clock. On the AM5728 gp-evm most of the timers are set to using the 20MHz system clock. Some of these timers are used by the other SOC drivers.

Which peripherals were planning to use in your system?

Best Regards,
Schuyler