Hi Bjorn, > -----Original Message----- > From: Bjorn Helgaas <helgaas@xxxxxxxxxx> > Sent: Tuesday, August 10, 2021 8:18 PM > To: George Cherian <gcherian@xxxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; > bhelgaas@xxxxxxxxxx > Subject: Re: [PATCH] PCI: Add ACS quirk for Cavium multi-function > devices > > On Tue, Aug 10, 2021 at 05:54:25PM +0530, George Cherian wrote: > > Some Cavium endpoints are implemented as multi-function devices > > without ACS capability, but they actually don't support peer-to-peer > > transactions. > > > > Add ACS quirks to declare DMA isolation. > > > > Apply te quirk for following devices > > 1. BGX device found on Octeon-TX (8xxx) 2. CGX device found on > > Octeon-TX2 (9xxx) 3. RPM device found on Octeon-TX3 (10xxx) > > > > Signed-off-by: George Cherian <george.cherian@xxxxxxxxxxx> > > --- > > drivers/pci/quirks.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index > > 6d74386eadc2..076932018494 100644 > > --- a/drivers/pci/quirks.c > > +++ b/drivers/pci/quirks.c > > @@ -4840,6 +4840,10 @@ static const struct pci_dev_acs_enabled { > > { 0x10df, 0x720, pci_quirk_mf_endpoint_acs }, /* Emulex Skyhawk-R > */ > > /* Cavium ThunderX */ > > { PCI_VENDOR_ID_CAVIUM, PCI_ANY_ID, pci_quirk_cavium_acs }, > > + /* Cavium multi-function devices */ > > + { PCI_VENDOR_ID_CAVIUM, 0xA026, pci_quirk_mf_endpoint_acs }, > > + { PCI_VENDOR_ID_CAVIUM, 0xA059, pci_quirk_mf_endpoint_acs }, > > + { PCI_VENDOR_ID_CAVIUM, 0xA060, pci_quirk_mf_endpoint_acs }, > > Is there a plan to add ACS capabilities to future devices, or is Cavium just > resigned to forever adding and backporting quirks? Yes, the plan is to get these fixed in future silicons. So that we won't be needing any quirks. > > > /* APM X-Gene */ > > { PCI_VENDOR_ID_AMCC, 0xE004, pci_quirk_xgene_acs }, > > /* Ampere Computing */ > > -- > > 2.25.1 > > Regards, -George