[cc += Jay, Felix] On Thu, Jun 22, 2023 at 02:02:12PM -0700, Smita Koralahalli wrote: > Would it be fair to just reuse pci_enable_atomic_ops_to_root() for > Atomic_Ops configuration? Hm, that's a good question. I'm not an expert on that corner of the PCI core. But indeed what you could try is amend that function to not only *set* PCI_EXP_DEVCTL2_ATOMIC_REQ if it's supported, but to also *clear* it if it's not supported. And you'd have to call pci_enable_atomic_ops_to_root() on enumeration, e.g. from pci_init_capabilities(). That should obviate the need to call pci_enable_atomic_ops_to_root() from drivers, so you could probably remove the call from all the drivers which currently call it (amdgpu, infiniband, mellanox), in one separate patch per driver. An then you could drop the EXPORT clause for pci_enable_atomic_ops_to_root() and make it private to the PCI core. So that would be 5 patches (enablement/disablement on enumeration, amendmend of the 3 drivers, making the call private). I'm not sure if anyone will cry foul if you do that but if you want to give it a try, go for it. :) I don't now why commit 430a23689dea, which introduced pci_enable_atomic_ops_to_root(), chose to add it as a library function which is only called from specific drivers, instead of universally enabling the feature for all devices. Adding the commit authors to cc so they can chime in. Thanks, Lukas
