octeontx2-pf: Forward error codes to VF

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2040643

commit a8db854
Author: Subbaraya Sundeep <sbhatta@marvell.com>
Date:   Fri Jan 21 12:04:46 2022 +0530

    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: d424b6c ("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>

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>

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 */