bnxt_en: Cap the size of HWRM_PORT_PHY_QCFG forwarded response

Firmware interface 1.10.2.118 has increased the size of
HWRM_PORT_PHY_QCFG response beyond the maximum size that can be
forwarded.  When the VF's link state is not the default auto state,
the PF will need to forward the response back to the VF to indicate
the forced state.  This regression may cause the VF to fail to
initialize.

Fix it by capping the HWRM_PORT_PHY_QCFG response to the maximum
96 bytes.  The SPEEDS2_SUPPORTED flag needs to be cleared because the
new speeds2 fields are beyond the legacy structure.  Also modify
bnxt_hwrm_fwd_resp() to print a warning if the message size exceeds 96
bytes to make this failure more obvious.

Fixes: 84a911d ("bnxt_en: Update firmware interface to 1.10.2.118")
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20240612231736.57823-1-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1434,6 +1434,57 @@ struct bnxt_l2_filter {
 	atomic_t		refcnt;
 };
 
+/* Compat version of hwrm_port_phy_qcfg_output capped at 96 bytes.  The
+ * first 95 bytes are identical to hwrm_port_phy_qcfg_output in bnxt_hsi.h.
+ * The last valid byte in the compat version is different.
+ */
+struct hwrm_port_phy_qcfg_output_compat {
+	__le16	error_code;
+	__le16	req_type;
+	__le16	seq_id;
+	__le16	resp_len;
+	u8	link;
+	u8	active_fec_signal_mode;
+	__le16	link_speed;
+	u8	duplex_cfg;
+	u8	pause;
+	__le16	support_speeds;
+	__le16	force_link_speed;
+	u8	auto_mode;
+	u8	auto_pause;
+	__le16	auto_link_speed;
+	__le16	auto_link_speed_mask;
+	u8	wirespeed;
+	u8	lpbk;
+	u8	force_pause;
+	u8	module_status;
+	__le32	preemphasis;
+	u8	phy_maj;
+	u8	phy_min;
+	u8	phy_bld;
+	u8	phy_type;
+	u8	media_type;
+	u8	xcvr_pkg_type;
+	u8	eee_config_phy_addr;
+	u8	parallel_detect;
+	__le16	link_partner_adv_speeds;
+	u8	link_partner_adv_auto_mode;
+	u8	link_partner_adv_pause;
+	__le16	adv_eee_link_speed_mask;
+	__le16	link_partner_adv_eee_link_speed_mask;
+	__le32	xcvr_identifier_type_tx_lpi_timer;
+	__le16	fec_cfg;
+	u8	duplex_state;
+	u8	option_flags;
+	char	phy_vendor_name[16];
+	char	phy_vendor_partnumber[16];
+	__le16	support_pam4_speeds;
+	__le16	force_pam4_link_speed;
+	__le16	auto_pam4_link_speed_mask;
+	u8	link_partner_pam4_adv_speeds;
+	u8	valid;
+};
+
 struct bnxt_link_info {
 	u8			phy_type;
 	u8			media_type;

drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c

@@ -950,8 +950,11 @@ static int bnxt_hwrm_fwd_resp(struct bnxt *bp, struct bnxt_vf_info *vf,
 	struct hwrm_fwd_resp_input *req;
 	int rc;
 
-	if (BNXT_FWD_RESP_SIZE_ERR(msg_size))
+	if (BNXT_FWD_RESP_SIZE_ERR(msg_size)) {
+		netdev_warn_once(bp->dev, "HWRM fwd response too big (%d bytes)\n",
+				 msg_size);
 		return -EINVAL;
+	}
 
 	rc = hwrm_req_init(bp, req, HWRM_FWD_RESP);
 	if (!rc) {
@@ -1085,7 +1088,7 @@ static int bnxt_vf_set_link(struct bnxt *bp, struct bnxt_vf_info *vf)
 		rc = bnxt_hwrm_exec_fwd_resp(
 			bp, vf, sizeof(struct hwrm_port_phy_qcfg_input));
 	} else {
-		struct hwrm_port_phy_qcfg_output phy_qcfg_resp = {0};
+		struct hwrm_port_phy_qcfg_output_compat phy_qcfg_resp = {};
 		struct hwrm_port_phy_qcfg_input *phy_qcfg_req;
 
 		phy_qcfg_req =
@@ -1096,6 +1099,11 @@ static int bnxt_vf_set_link(struct bnxt *bp, struct bnxt_vf_info *vf)
 		mutex_unlock(&bp->link_lock);
 		phy_qcfg_resp.resp_len = cpu_to_le16(sizeof(phy_qcfg_resp));
 		phy_qcfg_resp.seq_id = phy_qcfg_req->seq_id;
+		/* New SPEEDS2 fields are beyond the legacy structure, so
+		 * clear the SPEEDS2_SUPPORTED flag.
+		 */
+		phy_qcfg_resp.option_flags &=
+			~PORT_PHY_QCAPS_RESP_FLAGS2_SPEEDS2_SUPPORTED;
 		phy_qcfg_resp.valid = 1;
 
 		if (vf->flags & BNXT_VF_LINK_UP) {