Loongson PCIe 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.

Cc: stable@vger.kernel.org Signed-off-by: Xianglai Li lixianglai@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn --- drivers/pci/quirks.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 8d610c17e0f2..d52ec85f3382 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4995,6 +4995,18 @@ static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags) PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF); }

+static int pci_quirk_loongson_acs(struct pci_dev *dev, u16 acs_flags) +{ + /* + * Loongson PCIe 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. + */ + return pci_acs_ctrl_enabled(acs_flags, + PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF); +} + /* * Wangxun 40G/25G/10G/1G NICs have no ACS capability, but on * multi-function devices, the hardware isolates the functions by @@ -5128,6 +5140,9 @@ static const struct pci_dev_acs_enabled { { PCI_VENDOR_ID_BROADCOM, 0x1762, pci_quirk_mf_endpoint_acs }, { PCI_VENDOR_ID_BROADCOM, 0x1763, pci_quirk_mf_endpoint_acs }, { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs }, + /* Loongson PCIe Root Ports */ + { PCI_VENDOR_ID_LOONGSON, 0x3C09, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x3C19, pci_quirk_loongson_acs }, /* Amazon Annapurna Labs */ { PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031, pci_quirk_al_acs }, /* Zhaoxin multi-function devices */