On 09/05/18 07:40 AM, Christian König wrote: > The key takeaway is that when any device has ATS enabled you can't > disable ACS without breaking it (even if you unplug and replug it). I don't follow how you came to this conclusion... The ACS bits we'd be turning off are the ones that force TLPs addressed at a peer to go to the RC. However, ATS translation packets will be addressed to an untranslated address which a switch will not identify as a peer address so it should send upstream regardless the state of the ACS Req/Comp redirect bits. Once the translation comes back, the ATS endpoint should send the TLP to the peer address with the AT packet type and it will be directed to the peer provided the Direct Translated bit is set (or the redirect bits are unset). I can't see how turning off the Req/Comp redirect bits could break anything except for the isolation they provide. Logan
