Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 13 Jan 2023 10:36:37 +0800 | Subject | Re: [PATCH v2 1/1] PCI: Add translated request only flag for pci_enable_pasid() | From | Baolu Lu <> |
| |
On 2023/1/13 10:24, Tian, Kevin wrote: >> From: Lu Baolu <baolu.lu@linux.intel.com> >> Sent: Friday, January 13, 2023 9:44 AM >> >> One alternative is ATS which lets the device resolve the PASID+addr pair >> before a memory request is made into a routeable TLB address through the >> TA. Those resolved addresses are then cached on the device instead of >> in the IOMMU TLB and the device always sets the translated bit for PASID. >> One example of those devices are AMD graphic devices that always have ACS >> or ATS enabled together with PASID. > > this should be made clear that ATS alone doesn't imply that translated > bit is always set. It's just an optimization so the device may cache > translation for selective requests. Only combining with PRI to > support SVA has such implication. > >> + * @flags: device-specific flags >> + * - PCI_PASID_XLATED_REQ_ONLY: The PCI device only issues PASID >> + * memory requests of translated type. > > this reads like the device even doesn't issue non-PASID requests. > > It is clearer to be "The PCI device always use translated type for all > PASID memory requests". > > Otherwise looks good to me: > > Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Both make sense to me. It's updated. Thanks a lot!
-- Best regards, baolu
| ![\](/images/icornerr.gif) |