[Question] About scaling factor of Enhanced Counter Virtualization

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi all,

We are studying Enhanced Counter Virtualization (introduced by ARMv8.6 extension), and here is a question
raised by Biaoxiang Ye <yebiaoxiang@xxxxxxxxxx>:

Described in the ARMv8.6 Extension Specification:
Note: the scaling factor CNTSCALE is designed as a 2.62 bit fixed point number, so permitting a scaling up by
(nearly) a factor 4. The scaling factor CNTISCALE is signed as an 8.56 number for the scaling of the values
written into the timers for comparison with the actual count. This implies that the greatest scaling down of the
counter supported in (nearly) a factor of *512*.

We think the number "512" should be "256" (2^8), or do we miss something?

Thanks,
Keqian
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm



[Index of Archives]     [Linux KVM]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux