On 2/11/2019 2:15 PM, Raj, Ashok wrote:
It seems rather odd we have to check for ATS version.
I always assumed unspecified bits (Reserved) must be 0. We only check
this if ATS is enabled, and this particular bit wasn't given away for another
feature.
Is it really required to check for ATS version before consuming this?
Reading again, it looks like version check is not necessary since it
is implied by the presence of this bit per this paragraph.
Page Aligned Request – If Set, indicates the Untranslated Address is
always aligned to a 4096 byte boundary. Setting this bit is
recommended. This bit permits software to distinguish between
implementations compatible with earlier version of this specification
that permitted a requester to supply anything in bits [11:2].