Messages in this thread | | | Date | Thu, 16 Oct 2014 11:14:33 +0200 | From | Joerg Roedel <> | Subject | Re: PCIe PASID (Process Address Space ID) and iommu code |
| |
On Wed, Oct 15, 2014 at 09:50:58PM -0600, Bjorn Helgaas wrote: > [+cc Joerg, Suravee, Jay, iommu list, linux-pci] > > On Wed, Oct 15, 2014 at 5:44 PM, Kallol Biswas <nucleodyne@gmail.com> wrote: > > Resending, as message got bounced for html content. > > -------------------------------------------- > > Hi, > > PCIe has introduced PASID TLP Prefix. There are two ECNs on this. > > > > It seems that AMD iommu code makes use of PASID. Is there a device that > > utilizes this TLP prefix?
Yes, recent radeon GPUs can make use of the TLP prefix.
> > PASID allocation and management within a device is not clear to me. How > > does device know which PASID to issue for which virtual address? Who makes > > the association? Must be software/OS, but how? There is no table for this > > like MSI-X table.
The setup of the PASIDs is device specific, so there is no standard for setting up PASID address spaces on devices.
HTH,
Joerg
| |