[PATCH v4 05/10] PCI/AER: Apply function level reset to RCiEP on fatal error

From: Sean V Kelley
Date: Thu Sep 17 2020 - 12:29:54 EST


From: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>

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

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
---
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 e575fa6cee63..5380ecc41506 100644
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -169,6 +169,17 @@ static void pci_bridge_walk(struct pci_dev *bridge, int (*cb)(struct pci_dev *,
cb(bridge, userdata);
}

+static pci_ers_result_t 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,
pci_channel_state_t state,
pci_ers_result_t (*reset_subordinate_devices)(struct pci_dev *pdev))
@@ -195,15 +206,17 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
if (state == pci_channel_io_frozen) {
pci_bridge_walk(bridge, report_frozen_detected, &status);
if (type == PCI_EXP_TYPE_RC_END) {
- pci_warn(dev, "link reset not possible for RCiEP\n");
- status = PCI_ERS_RESULT_NONE;
- goto failed;
- }
-
- status = reset_subordinate_devices(bridge);
- if (status != PCI_ERS_RESULT_RECOVERED) {
- pci_warn(dev, "subordinate device 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_subordinate_devices(bridge);
+ if (status != PCI_ERS_RESULT_RECOVERED) {
+ pci_warn(dev, "subordinate device reset failed\n");
+ goto failed;
+ }
}
} else {
pci_bridge_walk(bridge, report_normal_detected, &status);
--
2.28.0