[net-next 04/12] i40e: Add delay after EMP reset for firmware to recover

[Jeff Kirsher <jeffrey.t.kirsher@intel.com>]

From: Filip Sadowski <filip.sadowski@intel.com>

This patch adds necessary delay for 4.33 firmware to recover after
EMP reset. Without this patch driver occasionally reinitializes
structures too quickly to communicate with firmware after EMP reset
causing AdminQ to timeout.

Signed-off-by: Filip Sadowski <filip.sadowski@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 005a6d6a20fb..a88fdb8bf5f0 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -9215,6 +9215,17 @@ static void i40e_rebuild(struct i40e_pf *pf, bool reinit, bool lock_acquired)
 	}
 	i40e_get_oem_version(&pf->hw);
 
+	if (test_bit(__I40E_EMP_RESET_INTR_RECEIVED, pf->state) &&
+	    ((hw->aq.fw_maj_ver == 4 && hw->aq.fw_min_ver <= 33) ||
+	     hw->aq.fw_maj_ver < 4) && hw->mac.type == I40E_MAC_XL710) {
+		/* The following delay is necessary for 4.33 firmware and older
+		 * to recover after EMP reset. 200 ms should suffice but we
+		 * put here 300 ms to be sure that FW is ready to operate
+		 * after reset.
+		 */
+		mdelay(300);
+	}
+
 	/* re-verify the eeprom if we just had an EMP reset */
 	if (test_and_clear_bit(__I40E_EMP_RESET_INTR_RECEIVED, pf->state))
 		i40e_verify_eeprom(pf);
-- 
2.14.3