Currently PCI_BRIDGE_CTL_SERR is being enabled only in
ACPI flow.
This bit is required for forwarding errors reported
by EP devices to upstream device.
This patch enables SERR# for Type-1 PCI device.

Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gog...@xilinx.com>
---
 drivers/pci/pcie/aer.c |   23 +++++++++++++++++++++++
 1 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index a2e8838..943e084 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -343,6 +343,19 @@ int pci_enable_pcie_error_reporting(struct pci_dev *dev)
        if (!dev->aer_cap)
                return -EIO;
 
+       if (!IS_ENABLED(CONFIG_ACPI) &&
+           dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+               u16 control;
+
+               /*
+                * A Type-1 PCI bridge will not forward ERR_ messages coming
+                * from an endpoint if SERR# forwarding is not enabled.
+                */
+               pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
+               control |= PCI_BRIDGE_CTL_SERR;
+               pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
+       }
+
        return pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_AER_FLAGS);
 }
 EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting);
@@ -352,6 +365,16 @@ int pci_disable_pcie_error_reporting(struct pci_dev *dev)
        if (pcie_aer_get_firmware_first(dev))
                return -EIO;
 
+       if (!IS_ENABLED(CONFIG_ACPI) &&
+           dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+               u16 control;
+
+               /* Clear SERR Forwarding */
+               pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
+               control &= ~PCI_BRIDGE_CTL_SERR;
+               pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
+       }
+
        return pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
                                          PCI_EXP_AER_FLAGS);
 }
-- 
1.7.1

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