[PATCH V2] PCI: Add ACS quirk for Ampere root ports

[Feng Kan]

The Ampere Computing PCIe root port does not support ACS at this point.
However, the hardware provides isolation and source validation through the
SMMU. The stream ID generated by the PCIe ports contain both the
bus/device/function number as well as the port ID in its 3 most significant
bits. Turn on ACS but disable all the peer-to-peer features.

Signed-off-by: Feng Kan <fkan@xxxxxxx>
---
 V2 - Correct patch summary as per Bjorn's comment

 This is a rebranding of APM to Ampere, it is a change of vendor id
 and device id, all functionality stays the same as before.

 drivers/pci/quirks.c    | 9 +++++++++
 include/linux/pci_ids.h | 1 +
 2 files changed, 10 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index fc73401..57748a3 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4514,6 +4514,15 @@ static const struct pci_dev_acs_enabled {
 	{ PCI_VENDOR_ID_CAVIUM, PCI_ANY_ID, pci_quirk_cavium_acs },
 	/* APM X-Gene */
 	{ PCI_VENDOR_ID_AMCC, 0xE004, pci_quirk_xgene_acs },
+	/* Ampere Computing */
+	{ PCI_VENDOR_ID_AMPERE, 0xE005, pci_quirk_xgene_acs },
+	{ PCI_VENDOR_ID_AMPERE, 0xE006, pci_quirk_xgene_acs },
+	{ PCI_VENDOR_ID_AMPERE, 0xE007, pci_quirk_xgene_acs },
+	{ PCI_VENDOR_ID_AMPERE, 0xE008, pci_quirk_xgene_acs },
+	{ PCI_VENDOR_ID_AMPERE, 0xE009, pci_quirk_xgene_acs },
+	{ 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 },
 	{ 0 }
 };
 
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index a6b3066..c875d42 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -1333,6 +1333,7 @@
 #define PCI_DEVICE_ID_IMS_TT3D		0x9135
 
 #define PCI_VENDOR_ID_AMCC		0x10e8
+#define PCI_VENDOR_ID_AMPERE		0x1def
 
 #define PCI_VENDOR_ID_INTERG		0x10ea
 #define PCI_DEVICE_ID_INTERG_1682	0x1682
-- 
2.7.4