[PATCH net 3/4] bnxt_en: Fix driver init in kdump kernel

The driver forces an FLR during kdump kernel initialization to reset
the device.  If the NIC is behind a PCIe switch in synthetic (smart)
mode, the switch may need to see that the BARs have been initialized
before it will pass Mem read/write TLPs to the NIC.  Save the PCI
state before FLR and restore the state after FLR.  The BARs have to
be cleared to ensure that they get re-initialized.

Fixes: 8743db4a9acf ("bnxt_en: Issue PCIe FLR in kdump kernel to cleanup pending DMAs.")
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <redacted>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index a76674fd0d6b..c3d561ac53dc 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -17091,7 +17091,10 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 */
 	if (is_kdump_kernel()) {
 		pci_clear_master(pdev);
+		pci_save_state(pdev);
 		pcie_flr(pdev);
+		bnxt_clear_bars(pdev);
+		pci_restore_state(pdev);
 	}
 
 	max_irqs = bnxt_get_max_irq(pdev);

-- 
2.51.0