octeontx2-pf: Forward error codes to VF

PF forwards its VF messages to AF and corresponding
replies from AF to VF. AF sets proper error code in the
replies after processing message requests. Currently PF
checks the error codes in replies and sends invalid
message to VF. This way VF lacks the information of
error code set by AF for its messages. This patch
changes that such that PF simply forwards AF replies
so that VF can handle error codes.

Fixes: d424b6c0 ("octeontx2-pf: Enable SRIOV and added VF mbox handling")
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c

@@ -394,7 +394,12 @@ static int otx2_forward_vf_mbox_msgs(struct otx2_nic *pf,
 		dst_mdev->msg_size = mbox_hdr->msg_size;
 		dst_mdev->num_msgs = num_msgs;
 		err = otx2_sync_mbox_msg(dst_mbox);
-		if (err) {
+		/* Error code -EIO indicate there is a communication failure
+		 * to the AF. Rest of the error codes indicate that AF processed
+		 * VF messages and set the error codes in response messages
+		 * (if any) so simply forward responses to VF.
+		 */
+		if (err == -EIO) {
 			dev_warn(pf->dev,
 				 "AF not responding to VF%d messages\n", vf);
 			/* restore PF mbase and exit */