Does it mean it can't be switched to lower frequency ?
Or the 1GHz just represents the base frequency, the system counter still can switch to lower frequency such as 50MHz, 100MHz, etc ?
Hi there, I have moved your question to the Cortex-A/A-profile forum. Many thanks.
The manual reads like this. Always 1ns resolution and always 1GHz clock.
Of course, if the chip does no run at 1GHz, the counter won't run at 1GHz, but it seems, one cannot adjust it any more by larger increments.
Then how to understand the words "Though each unit of the counter is set to 1ns, this does not require that the counter is incremented every 1ns. A step in the counter might be more than a single bit increment. It is recommended that the count is not incremented at a rate that is less than 50MHz in normal running operation." ? Does it not mean that it can still be switched to lower frequency?
The manual always says "from 8.0 to 8.5 ..." whenever it comes to lower frequencies.Though I see that the "note" you are referring might be intended for 8.0 to 8.6.
Maybe some ARM employee can fill the gap. ;-)