The manual say the frequency of generic timers in armv8 is typically in the range of 1MHz to 50MHz. So dese the frequency is software changeable?
The CNTFRQ_EL0 is used to tell the os the current frequency of the timer. Thus, can we directly write a value into it to change the frequency? If the soc is implemented with the EL3, can we still change the frequency of the timers in EL1?
If we cannot write the CNTFRQ_EL0, then may I ask who determines the frequency of the generic timer?
Really thx for the possible response!
whether or not the generic timer's frequency can be changed depends on the SoC. Mostly not. EL3 or the boot loader will set CNTFRQ_EL0 for EL1/EL0 to know.
Thanks for your reply! May I make sure from you this: CNTFRQ_EL0 is never a register to set the frequency but only a message provider. Is it correct?
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