bnxt_en: Report firmware DCBX agent.

Report DCB_CAP_DCBX_LLD_MANAGED only if the firmware DCBX agent is enabled
and running for PF or VF.  Otherwise, if both LLDP and DCBX agents are
disabled in firmware, we report DCB_CAP_DCBX_LLD_HOST and allow host
IEEE DCB settings.  This patch refines the current logic in the driver.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -4578,6 +4578,7 @@ static int bnxt_hwrm_func_qcfg(struct bnxt *bp)
 {
 	struct hwrm_func_qcfg_input req = {0};
 	struct hwrm_func_qcfg_output *resp = bp->hwrm_cmd_resp_addr;
+	u16 flags;
 	int rc;
 
 	bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_FUNC_QCFG, -1, -1);
@@ -4594,15 +4595,15 @@ static int bnxt_hwrm_func_qcfg(struct bnxt *bp)
 		vf->vlan = le16_to_cpu(resp->vlan) & VLAN_VID_MASK;
 	}
 #endif
-	if (BNXT_PF(bp)) {
-		u16 flags = le16_to_cpu(resp->flags);
-
+	flags = le16_to_cpu(resp->flags);
 	if (flags & (FUNC_QCFG_RESP_FLAGS_FW_DCBX_AGENT_ENABLED |
-			     FUNC_QCFG_RESP_FLAGS_FW_LLDP_AGENT_ENABLED))
+		     FUNC_QCFG_RESP_FLAGS_FW_LLDP_AGENT_ENABLED)) {
 		bp->flags |= BNXT_FLAG_FW_LLDP_AGENT;
-		if (flags & FUNC_QCFG_RESP_FLAGS_MULTI_HOST)
-			bp->flags |= BNXT_FLAG_MULTI_HOST;
+		if (flags & FUNC_QCFG_RESP_FLAGS_FW_DCBX_AGENT_ENABLED)
+			bp->flags |= BNXT_FLAG_FW_DCBX_AGENT;
 	}
+	if (BNXT_PF(bp) && (flags & FUNC_QCFG_RESP_FLAGS_MULTI_HOST))
+		bp->flags |= BNXT_FLAG_MULTI_HOST;
 
 	switch (resp->port_partition_type) {
 	case FUNC_QCFG_RESP_PORT_PARTITION_TYPE_NPAR1_0:

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

@@ -1027,6 +1027,7 @@ struct bnxt {
 	#define BNXT_FLAG_MULTI_HOST	0x100000
 	#define BNXT_FLAG_SHORT_CMD	0x200000
 	#define BNXT_FLAG_DOUBLE_DB	0x400000
+	#define BNXT_FLAG_FW_DCBX_AGENT	0x800000
 	#define BNXT_FLAG_CHIP_NITRO_A0	0x1000000
 
 	#define BNXT_FLAG_ALL_CONFIG_FEATS (BNXT_FLAG_TPA |		\

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

@@ -549,13 +549,18 @@ static u8 bnxt_dcbnl_setdcbx(struct net_device *dev, u8 mode)
 {
 	struct bnxt *bp = netdev_priv(dev);
 
-	/* only support IEEE */
-	if ((mode & DCB_CAP_DCBX_VER_CEE) || !(mode & DCB_CAP_DCBX_VER_IEEE))
+	/* All firmware DCBX settings are set in NVRAM */
+	if (bp->dcbx_cap & DCB_CAP_DCBX_LLD_MANAGED)
 		return 1;
 
 	if (mode & DCB_CAP_DCBX_HOST) {
 		if (BNXT_VF(bp) || (bp->flags & BNXT_FLAG_FW_LLDP_AGENT))
 			return 1;
+
+		/* only support IEEE */
+		if ((mode & DCB_CAP_DCBX_VER_CEE) ||
+		    !(mode & DCB_CAP_DCBX_VER_IEEE))
+			return 1;
 	}
 
 	if (mode == bp->dcbx_cap)
@@ -584,7 +589,7 @@ void bnxt_dcb_init(struct bnxt *bp)
 	bp->dcbx_cap = DCB_CAP_DCBX_VER_IEEE;
 	if (BNXT_PF(bp) && !(bp->flags & BNXT_FLAG_FW_LLDP_AGENT))
 		bp->dcbx_cap |= DCB_CAP_DCBX_HOST;
-	else
+	else if (bp->flags & BNXT_FLAG_FW_DCBX_AGENT)
 		bp->dcbx_cap |= DCB_CAP_DCBX_LLD_MANAGED;
 	bp->dev->dcbnl_ops = &dcbnl_ops;
 }