PCI/ERR: Return status of pcie_do_recovery()

As per the DPC Enhancements ECN [1], sec 4.5.1, table 4-4, if the OS
supports Error Disconnect Recover (EDR), it must invalidate the software
state associated with child devices of the port without attempting to
access the child device hardware. In addition, if the OS supports DPC, it
must attempt to recover the child devices if the port implements the DPC
Capability. If the OS continues operation, the OS must inform the firmware
of the status of the recovery operation via the _OST method.

Return the result of pcie_do_recovery() so we can report it to firmware via
_OST.

[1] Downstream Port Containment Related Enhancements ECN, Jan 28, 2019,
    affecting PCI Firmware Specification, Rev. 3.2
    https://members.pcisig.com/wg/PCI-SIG/document/12888

Link: https://lore.kernel.org/r/eb60ec89448769349c6722954ffbf2de163155b5.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 3e5efb83e9a22271cb03a095cf8c127d14db054b..efbe94096050d8bb0b3eec89c70f4628b48ed6b2 100644 (file)
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -547,8 +547,9 @@ static inline int pci_dev_specific_disable_acs_redir(struct pci_dev *dev)
 #endif
 
 /* PCI error reporting and recovery */
-void pcie_do_recovery(struct pci_dev *dev, enum pci_channel_state state,
-                     pci_ers_result_t (*reset_link)(struct pci_dev *pdev));
+pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
+                       enum pci_channel_state state,
+                       pci_ers_result_t (*reset_link)(struct pci_dev *pdev));
 
 bool pcie_wait_for_link(struct pci_dev *pdev, bool active);
 #ifdef CONFIG_PCIEASPM

diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
index 9d5b71a7f8371efa7ba860e86308f674fa1b2caa..0c40488da651a330ec36bf8cec2ebcefbff4e446 100644 (file)
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -146,9 +146,9 @@ out:
        return 0;
 }
 
-void pcie_do_recovery(struct pci_dev *dev,
-                     enum pci_channel_state state,
-                     pci_ers_result_t (*reset_link)(struct pci_dev *pdev))
+pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
+                       enum pci_channel_state state,
+                       pci_ers_result_t (*reset_link)(struct pci_dev *pdev))
 {
        pci_ers_result_t status = PCI_ERS_RESULT_CAN_RECOVER;
        struct pci_bus *bus;
@@ -200,11 +200,13 @@ void pcie_do_recovery(struct pci_dev *dev,
        pci_aer_clear_device_status(dev);
        pci_cleanup_aer_uncorrect_error_status(dev);
        pci_info(dev, "device recovery successful\n");
-       return;
+       return status;
 
 failed:
        pci_uevent_ers(dev, PCI_ERS_RESULT_DISCONNECT);
 
        /* TODO: Should kernel panic here? */
        pci_info(dev, "device recovery failed\n");
+
+       return status;
 }