[PATCH 2/2][Bionic][SRU Artful] PCI: Apply Cavium ThunderX ACS quirk to more Root Ports

[dann frazier]

From: Vadim Lomovtsev <Vadim.Lomovtsev at cavium.com>

BugLink: https://bugs.launchpad.net/bugs/1736774

Extend the Cavium ThunderX ACS quirk to cover more device IDs and restrict
it to only Root Ports.

Signed-off-by: Vadim Lomovtsev <Vadim.Lomovtsev at cavium.com>
[bhelgaas: changelog, stable tag]
Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
Cc: stable at vger.kernel.org	# v4.12+
(cherry picked from commit f2ddaf8dfd4a5071ad09074d2f95ab85d35c8a1e)
Signed-off-by: dann frazier <dann.frazier at canonical.com>
---
 drivers/pci/quirks.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index fcf734231c4d..99eec22d99b7 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4250,6 +4250,19 @@ static int pci_quirk_amd_sb_acs(struct pci_dev *dev, u16 acs_flags)
 #endif
 }
 
+static bool pci_quirk_cavium_acs_match(struct pci_dev *dev)
+{
+	/*
+	 * Effectively selects all downstream ports for whole ThunderX 1
+	 * family by 0xf800 mask (which represents 8 SoCs), while the lower
+	 * bits of device ID are used to indicate which subdevice is used
+	 * within the SoC.
+	 */
+	return (pci_is_pcie(dev) &&
+		(pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) &&
+		((dev->device & 0xf800) == 0xa000));
+}
+
 static int pci_quirk_cavium_acs(struct pci_dev *dev, u16 acs_flags)
 {
 	/*
@@ -4262,7 +4275,7 @@ static int pci_quirk_cavium_acs(struct pci_dev *dev, u16 acs_flags)
 	 */
 	acs_flags &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_SV | PCI_ACS_UF);
 
-	if (!((dev->device >= 0xa000) && (dev->device <= 0xa0ff)))
+	if (!pci_quirk_cavium_acs_match(dev))
 		return -ENOTTY;
 
 	return acs_flags ? 0 : 1;
-- 
2.15.1