Re: MTIME update frequency


Greg Favor
 

>Based on above points, I still think mandating fixed MTIME resolution is desirable for OS-A platforms and this has nothing to do with how timebase-frequency is discovered (i.e. DT/ACPI).
If we do want to fix the resolution then the 10ns is too coarse. I suggest we make it at least 1ns to address the requirements of systems many of us are building. With 10ns resolution it will not be competitive against ARM systems that as you noted have fixed resolution to 1ns or x86 where TSC operates at P0 frequency.

Note that ARM SBSA did not mandate a 1 GHz update rate; it only mandated a 1ns resolution - and explicitly acknowledged that updates may be at a lower rate using counter scaling.

Greg

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