On Tue, 18 Feb 2020 at 00:50, Richard Henderson <richard.hender...@linaro.org> wrote: > It isn't clear to me that DC ZVA does check tags. There's no pseudocode for > DC_ZVA, which is less helpful than it might be. > > I suppose one could infer it from "behaves as a set of stores to each byte > within the block", but considering that stores are both checking or > non-checking depending on addressing mode etc, I'd have preferred an explicit > note. > > So far I'm treating DC_ZVA as unchecked.
I think the spec is reasonably clear here. In D6.8 it says "Unless an access is explicitly defined as a Tag Unchecked access it is a Tag Checked access." and then in D6.8.1: "A cache maintenance by virtual address operation other than DC ZVA generates a Tag Unchecked access." So DC ZVA is Tag Checked, other DC ops that take a VA are Tag Unchecked. thanks -- PMM
