diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 15ee4e9af633eb8d74b27ac0f246802a06724ffd..92bea8accc351083937790773235da3f78d74a93 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4137,6 +4137,18 @@ static int pci_quirk_cavium_acs(struct pci_dev *dev, u16 acs_flags)
 	return acs_flags ? 0 : 1;
 }
 
+static int pci_quirk_xgene_acs(struct pci_dev *dev, u16 acs_flags)
+{
+	/*
+	 * X-Gene root matching this quirk do not allow peer-to-peer
+	 * transactions with others, allowing masking out these bits as if they
+	 * were unimplemented in the ACS capability.
+	 */
+	acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
+
+	return acs_flags ? 0 : 1;
+}
+
 /*
  * Many Intel PCH root ports do provide ACS-like features to disable peer
  * transactions and validate bus numbers in requests, but do not provide an
@@ -4385,6 +4397,8 @@ 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 },
+	/* APM X-Gene */
+	{ PCI_VENDOR_ID_AMCC, 0xE004, pci_quirk_xgene_acs },
 	{ 0 }
 };