fm10k: don't stop reset due to FM10K_ERR_REQUESTS_PENDING

Don't report FM10K_ERR_REQUESTS_PENDING when we fail to disable queues
within the timeout. This can occur due to a hardware Tx hang, or when
the switch ethernet fabric is resetting while we are transmitting
traffic. It can sometimes take up to 500ms before the Tx DMA engine
gives up. Instead, just skip the DMA engine check and perform
a data-path reset anyways. Add a statistic counter to keep track of the
number of resets occurring while we have pending DMA on the rings.

In order to prevent having to re-assign err to 0, re-order the
last few items of the reset_hw_pf function so that we don't perform
"return err" at the end.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_vf.c b/drivers/net/ethernet/intel/fm10k/fm10k_vf.c
index 3b06685e..337ba65 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_vf.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_vf.c
@@ -34,7 +34,7 @@
 
 	/* we need to disable the queues before taking further steps */
 	err = fm10k_stop_hw_generic(hw);
-	if (err)
+	if (err && err != FM10K_ERR_REQUESTS_PENDING)
 		return err;
 
 	/* If permanent address is set then we need to restore it */
@@ -67,7 +67,7 @@
 		fm10k_write_reg(hw, FM10K_TDLEN(i), tdlen);
 	}
 
-	return 0;
+	return err;
 }
 
 /**
@@ -83,7 +83,9 @@
 
 	/* shut down queues we own and reset DMA configuration */
 	err = fm10k_stop_hw_vf(hw);
-	if (err)
+	if (err == FM10K_ERR_REQUESTS_PENDING)
+		hw->mac.reset_while_pending++;
+	else if (err)
 		return err;
 
 	/* Inititate VF reset */
@@ -96,9 +98,9 @@
 	/* Clear reset bit and verify it was cleared */
 	fm10k_write_reg(hw, FM10K_VFCTRL, 0);
 	if (fm10k_read_reg(hw, FM10K_VFCTRL) & FM10K_VFCTRL_RST)
-		err = FM10K_ERR_RESET_FAILED;
+		return FM10K_ERR_RESET_FAILED;
 
-	return err;
+	return 0;
 }
 
 /**