6.6-stable review patch. If anyone has any objections, please let me know.
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From: Huacai Chen chenhuacai@loongson.cn
commit 1f3303aa92e15fa273779acac2d0023609de30f1 upstream.
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.
Signed-off-by: Xianglai Li lixianglai@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Bjorn Helgaas bhelgaas@google.com Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250403040756.720409-1-chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/quirks.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)
--- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4988,6 +4988,18 @@ static int pci_quirk_brcm_acs(struct pci 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 @@ -5121,6 +5133,17 @@ 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 }, + { PCI_VENDOR_ID_LOONGSON, 0x3C29, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A09, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A19, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A29, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A39, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A49, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A59, pci_quirk_loongson_acs }, + { PCI_VENDOR_ID_LOONGSON, 0x7A69, pci_quirk_loongson_acs }, /* Amazon Annapurna Labs */ { PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031, pci_quirk_al_acs }, /* Zhaoxin multi-function devices */