[RFC PATCH 5/9] PCI/AER: Apply function level reset to RCiEP on fatal error

[Sean V Kelley]

From: Qiuxu Zhuo <qiuxu.z...@intel.com>

Attempt to do function level reset for an RCiEP associated with an
RCEC device on fatal error.

Signed-off-by: Qiuxu Zhuo <qiuxu.z...@intel.com>
---
 drivers/pci/pcie/err.c | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
index 044df004f20b..9b3ec94bdf1d 100644
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -170,6 +170,17 @@ static void pci_walk_dev_affected(struct pci_dev *dev, int 
(*cb)(struct pci_dev
        }
 }
 
+static enum pci_channel_state flr_on_rciep(struct pci_dev *dev)
+{
+       if (!pcie_has_flr(dev))
+               return PCI_ERS_RESULT_NONE;
+
+       if (pcie_flr(dev))
+               return PCI_ERS_RESULT_DISCONNECT;
+
+       return PCI_ERS_RESULT_RECOVERED;
+}
+
 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))
@@ -191,15 +202,17 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
        if (state == pci_channel_io_frozen) {
                pci_walk_dev_affected(dev, report_frozen_detected, &status);
                if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
-                       pci_warn(dev, "link reset not possible for RCiEP\n");
-                       status = PCI_ERS_RESULT_NONE;
-                       goto failed;
-               }
-
-               status = reset_link(dev);
-               if (status != PCI_ERS_RESULT_RECOVERED) {
-                       pci_warn(dev, "link reset failed\n");
-                       goto failed;
+                       status = flr_on_rciep(dev);
+                       if (status != PCI_ERS_RESULT_RECOVERED) {
+                               pci_warn(dev, "function level reset failed\n");
+                               goto failed;
+                       }
+               } else {
+                       status = reset_link(dev);
+                       if (status != PCI_ERS_RESULT_RECOVERED) {
+                               pci_warn(dev, "link reset failed\n");
+                               goto failed;
+                       }
                }
        } else {
                pci_walk_dev_affected(dev, report_normal_detected, &status);
-- 
2.27.0