From: Suneel Garapati <sgarapati@xxxxxxxxxxx>
Some AER interrupt capability registers may not be present on
non Root ports. Since there is no way to check presence of
ROOT_ERR_COMMAND and ROOT_ERR_STATUS registers. Allow AER
service only on root ports.
Otherwise AER interrupt message number is read incorrectly
causing MSIX vector registration to fail and fallback to legacy
unnecessarily.
Signed-off-by: Suneel Garapati <sgarapati@xxxxxxxxxxx>
Reviewed-by: Chandrakala Chavva <cchavva@xxxxxxxxxxx>
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@xxxxxxxxxxx>
---
drivers/pci/pcie/portdrv_core.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 3ee63968deaa..edc355971a32 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -221,7 +221,16 @@ static int get_port_device_capability(struct pci_dev *dev)
}
#ifdef CONFIG_PCIEAER
+ /*
+ * Some AER interrupt capability registers may not be present on
+ * non Root ports. Since there is no way to check presence of
+ * ROOT_ERR_COMMAND and ROOT_ERR_STATUS registers. Allow AER
+ * service only on root ports. Refer PCIe rev5.0 spec v1.0 7.8.4.
+ * Otherwise AER interrupt message number is read incorrectly
+ * causing MSIX vector registration to fail and fallback to legacy.
+ */
if (dev->aer_cap && pci_aer_available() &&
+ pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
(pcie_ports_native || host->native_aer)) {
services |= PCIE_PORT_SERVICE_AER;
--
2.25.1
