Re: [PATCH v3 1/3] PCI: Allow ATS to be always on for CXL.cache capable devices

From: Jason Gunthorpe

Date: Thu Mar 26 2026 - 17:52:54 EST


On Thu, Mar 26, 2026 at 04:38:54PM -0500, Bjorn Helgaas wrote:

> It's only called from arm-smmu-v3.c. Is there something unique about
> SMMU, or will other IOMMUs need something similar?

Yeah, every iommu driver will eventually want to use this. IIRC the
motivation for using the pci core was to make use of pci quirks.

Right now ARM is the only one that turns ATS off for identity, but
IMHO those are bugs in the other drivers to not do that.

Jason