From: Abhinav Ratna <abhinav.ratna@broadcom.com> [ Upstream commit 46b2c32df7a462d0e64b68c513e5c4c1b2a399a7 ] iProc PAXB Root Ports don't advertise an ACS capability, but they do not allow peer-to-peer transactions between Root Ports. Add an ACS quirk so each Root Port can be in a separate IOMMU group. [bhelgaas: commit log, comment, use common implementation style] Link: https://lore.kernel.org/r/1566275985-25670-1-git-send-email-srinath.mannam@b... Signed-off-by: Abhinav Ratna <abhinav.ratna@broadcom.com> Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/pci/quirks.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index ae81bb63560c..66c4d17205bd 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4543,6 +4543,19 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags) return acs_flags ? 0 : 1; } +static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags) +{ + /* + * iProc PAXB Root Ports don't advertise an ACS capability, but + * they do not allow peer-to-peer transactions between Root Ports. + * Allow each Root Port to be in a separate IOMMU group by masking + * SV/RR/CR/UF bits. + */ + acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF); + + return acs_flags ? 0 : 1; +} + static const struct pci_dev_acs_enabled { u16 vendor; u16 device; @@ -4636,6 +4649,7 @@ static const struct pci_dev_acs_enabled { { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs }, { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs }, { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs }, + { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs }, { 0 } }; -- 2.25.1