[PATCH net v2] octeontx2-pf: check DMAC extraction support before filtering

[<nshettyj@marvell.com>]

From: Suman Ghosh <sumang@marvell.com>

Currently, configuring a VF MAC address via the PF (e.g., 'ip link
set <pf> vf 0 mac <mac>') blindly attempts to install a DMAC-based
hardware filter. However, the hardware parser profile might not
support DMAC extraction.

Check if the hardware parsing profile supports DMAC extraction
before adding the filter. Additionally, emit a warning message
to inform the operator if the MAC filter installation fails due
to missing DMAC extraction support.

Fixes: f0c2982aaf98 ("octeontx2-pf: Add support for SR-IOV management functions")
Signed-off-by: Suman Ghosh <sumang@marvell.com>
Signed-off-by: Nitin Shetty J <nshettyj@marvell.com>

---
v2:
 - Move the DMAC extraction check from otx2_set_vf_mac() into
   otx2_do_set_vf_mac() which already holds pf->mbox.lock, so all
   mbox operations are under a single lock/unlock pair. All error
   paths now use the existing goto-out pattern, eliminating the
   scattered mutex_unlock() + return calls from v1.
 - Return -EOPNOTSUPP instead of 0 when DMAC extraction is not
   supported, so the caller gets an explicit error rather than a
   silent success.
---
 .../ethernet/marvell/octeontx2/nic/otx2_pf.c  | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
index b63df5737ff2..dc7e4a225dd0 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
@@ -2517,10 +2517,43 @@ EXPORT_SYMBOL(otx2_config_hwtstamp_set);
 
 static int otx2_do_set_vf_mac(struct otx2_nic *pf, int vf, const u8 *mac)
 {
+	struct npc_get_field_status_req *freq;
+	struct npc_get_field_status_rsp *frsp;
 	struct npc_install_flow_req *req;
 	int err;
 
 	mutex_lock(&pf->mbox.lock);
+
+	/* Skip installing the DMAC filter if the hardware parser profile
+	 * does not support DMAC extraction.
+	 */
+	freq = otx2_mbox_alloc_msg_npc_get_field_status(&pf->mbox);
+	if (!freq) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	freq->field = NPC_DMAC;
+	if (otx2_sync_mbox_msg(&pf->mbox)) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	frsp = (struct npc_get_field_status_rsp *)otx2_mbox_get_rsp
+	       (&pf->mbox.mbox, 0, &freq->hdr);
+	if (IS_ERR(frsp)) {
+		err = PTR_ERR(frsp);
+		goto out;
+	}
+
+	if (!frsp->enable) {
+		netdev_warn(pf->netdev,
+			    "VF %d MAC filter not installed: DMAC extraction not supported by parser profile\n",
+			    vf);
+		err = -EOPNOTSUPP;
+		goto out;
+	}
+
 	req = otx2_mbox_alloc_msg_npc_install_flow(&pf->mbox);
 	if (!req) {
 		err = -ENOMEM;
-- 
2.48.1