PCI: Disable MSI on RDC PCI to PCIe bridges

[ Upstream commit ebc7086b39e5e4f3d3ca82caaea20538c9b62d42 ]

RDC PCI to PCIe bridges, present on Vortex86DX3 and Vortex86EX2 SoCs, do
not support MSIs. If enabled, interrupts generated by PCIe devices never
reach the processor.

I have contacted the manufacturer (DM&P) and they confirmed that PCI MSIs
need to be disabled for them.

Signed-off-by: Marcos Del Sol Vives <marcos@orca.pet>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250705233209.721507-1-marcos@orca.pet
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 2733ca94434dc4b91eabec60a16c0c6674caa0f3..e9aed73cfd5f6163054d0f421eaad94419597792 100644 (file)
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -2541,6 +2541,7 @@ static void quirk_disable_msi(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8131_BRIDGE, quirk_disable_msi);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, 0xa238, quirk_disable_msi);
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x5a3f, quirk_disable_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_RDC, 0x1031, quirk_disable_msi);
 
 /*
  * The APC bridge device in AMD 780 family northbridges has some random