[PATCH v4 7/8] PCI/DPC: Add support for DPC recovery on NON_FATAL errors

From: sathyanarayanan . kuppuswamy
Date: Wed Jul 03 2019 - 16:32:26 EST


From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Currently, in native mode, DPC driver is configured to trigger DPC only
for FATAL errors and hence it only supports port recovery for FATAL
errors. But with Error Disconnect Recover (EDR) support, DPC
configuration is done by firmware, and hence we should expect DPC
triggered for both FATAL/NON-FATAL errors. So add support for DPC
recovery with NON-FATAL errors.

Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
---
drivers/pci/pcie/dpc.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 214fa623228e..34f4e6ca24df 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -267,15 +267,20 @@ static void dpc_process_error(struct dpc_dev *dpc)
/* show RP PIO error detail information */
if (dpc->rp_extensions && reason == 3 && ext_reason == 0)
dpc_process_rp_pio_error(dpc);
- else if (reason == 0 &&
+ else if (reason <= 2 &&
dpc_get_aer_uncorrect_severity(pdev, &info) &&
aer_get_device_error_info(pdev, &info)) {
aer_print_error(pdev, &info);
pci_cleanup_aer_uncorrect_error_status(pdev);
- pci_aer_clear_fatal_status(pdev);
+ if (reason != 1)
+ pci_aer_clear_fatal_status(pdev);
}

- /* We configure DPC so it only triggers on ERR_FATAL */
+ /*
+ * Irrespective of whether the DPC event is triggered by
+ * ERR_FATAL or ERR_NONFATAL, since the link is already down,
+ * use the FATAL error recovery path for both cases.
+ */
pcie_do_recovery(pdev, pci_channel_io_frozen, PCIE_PORT_SERVICE_DPC);
}

--
2.21.0