bnxt_en: Add DCBNL DSCP application protocol support.

Expand the .ieee_setapp() and ieee_delapp() DCBNL methods to support
DSCP.  This allows DSCP values to user priority mappings instead
of using VLAN priorities.  Each DSCP mapping is added or deleted one
entry at a time using the firmware API.  The firmware call can only be
made from a PF.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -1281,6 +1281,7 @@ struct bnxt {
 	struct ieee_ets		*ieee_ets;
 	u8			dcbx_cap;
 	u8			default_pri;
+	u8			max_dscp_value;
 #endif /* CONFIG_BNXT_DCB */
 
 	u32			msg_enable;

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

@@ -385,6 +385,61 @@ static int bnxt_hwrm_set_dcbx_app(struct bnxt *bp, struct dcb_app *app,
 	return rc;
 }
 
+static int bnxt_hwrm_queue_dscp_qcaps(struct bnxt *bp)
+{
+	struct hwrm_queue_dscp_qcaps_output *resp = bp->hwrm_cmd_resp_addr;
+	struct hwrm_queue_dscp_qcaps_input req = {0};
+	int rc;
+
+	if (bp->hwrm_spec_code < 0x10800 || BNXT_VF(bp))
+		return 0;
+
+	bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_QUEUE_DSCP_QCAPS, -1, -1);
+	mutex_lock(&bp->hwrm_cmd_lock);
+	rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+	if (!rc) {
+		bp->max_dscp_value = (1 << resp->num_dscp_bits) - 1;
+		if (bp->max_dscp_value < 0x3f)
+			bp->max_dscp_value = 0;
+	}
+
+	mutex_unlock(&bp->hwrm_cmd_lock);
+	return rc;
+}
+
+static int bnxt_hwrm_queue_dscp2pri_cfg(struct bnxt *bp, struct dcb_app *app,
+					bool add)
+{
+	struct hwrm_queue_dscp2pri_cfg_input req = {0};
+	struct bnxt_dscp2pri_entry *dscp2pri;
+	dma_addr_t mapping;
+	int rc;
+
+	if (bp->hwrm_spec_code < 0x10800)
+		return 0;
+
+	bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_QUEUE_DSCP2PRI_CFG, -1, -1);
+	dscp2pri = dma_alloc_coherent(&bp->pdev->dev, sizeof(*dscp2pri),
+				      &mapping, GFP_KERNEL);
+	if (!dscp2pri)
+		return -ENOMEM;
+
+	req.src_data_addr = cpu_to_le64(mapping);
+	dscp2pri->dscp = app->protocol;
+	if (add)
+		dscp2pri->mask = 0x3f;
+	else
+		dscp2pri->mask = 0;
+	dscp2pri->pri = app->priority;
+	req.entry_cnt = cpu_to_le16(1);
+	rc = hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+	if (rc)
+		rc = -EIO;
+	dma_free_coherent(&bp->pdev->dev, sizeof(*dscp2pri), dscp2pri,
+			  mapping);
+	return rc;
+}
+
 static int bnxt_ets_validate(struct bnxt *bp, struct ieee_ets *ets, u8 *tc)
 {
 	int total_ets_bw = 0;
@@ -551,15 +606,30 @@ static int bnxt_dcbnl_ieee_setpfc(struct net_device *dev, struct ieee_pfc *pfc)
 	return rc;
 }
 
+static int bnxt_dcbnl_ieee_dscp_app_prep(struct bnxt *bp, struct dcb_app *app)
+{
+	if (app->selector == IEEE_8021QAZ_APP_SEL_DSCP) {
+		if (!bp->max_dscp_value)
+			return -ENOTSUPP;
+		if (app->protocol > bp->max_dscp_value)
+			return -EINVAL;
+	}
+	return 0;
+}
+
 static int bnxt_dcbnl_ieee_setapp(struct net_device *dev, struct dcb_app *app)
 {
 	struct bnxt *bp = netdev_priv(dev);
-	int rc = -EINVAL;
+	int rc;
 
 	if (!(bp->dcbx_cap & DCB_CAP_DCBX_VER_IEEE) ||
 	    !(bp->dcbx_cap & DCB_CAP_DCBX_HOST))
 		return -EINVAL;
 
+	rc = bnxt_dcbnl_ieee_dscp_app_prep(bp, app);
+	if (rc)
+		return rc;
+
 	rc = dcb_ieee_setapp(dev, app);
 	if (rc)
 		return rc;
@@ -570,6 +640,9 @@ static int bnxt_dcbnl_ieee_setapp(struct net_device *dev, struct dcb_app *app)
 	     app->protocol == ROCE_V2_UDP_DPORT))
 		rc = bnxt_hwrm_set_dcbx_app(bp, app, true);
 
+	if (app->selector == IEEE_8021QAZ_APP_SEL_DSCP)
+		rc = bnxt_hwrm_queue_dscp2pri_cfg(bp, app, true);
+
 	return rc;
 }
 
@@ -582,6 +655,10 @@ static int bnxt_dcbnl_ieee_delapp(struct net_device *dev, struct dcb_app *app)
 	    !(bp->dcbx_cap & DCB_CAP_DCBX_HOST))
 		return -EINVAL;
 
+	rc = bnxt_dcbnl_ieee_dscp_app_prep(bp, app);
+	if (rc)
+		return rc;
+
 	rc = dcb_ieee_delapp(dev, app);
 	if (rc)
 		return rc;
@@ -591,6 +668,9 @@ static int bnxt_dcbnl_ieee_delapp(struct net_device *dev, struct dcb_app *app)
 	     app->protocol == ROCE_V2_UDP_DPORT))
 		rc = bnxt_hwrm_set_dcbx_app(bp, app, false);
 
+	if (app->selector == IEEE_8021QAZ_APP_SEL_DSCP)
+		rc = bnxt_hwrm_queue_dscp2pri_cfg(bp, app, false);
+
 	return rc;
 }
 
@@ -642,6 +722,7 @@ void bnxt_dcb_init(struct bnxt *bp)
 	if (bp->hwrm_spec_code < 0x10501)
 		return;
 
+	bnxt_hwrm_queue_dscp_qcaps(bp);
 	bp->dcbx_cap = DCB_CAP_DCBX_VER_IEEE;
 	if (BNXT_PF(bp) && !(bp->fw_cap & BNXT_FW_CAP_LLDP_AGENT))
 		bp->dcbx_cap |= DCB_CAP_DCBX_HOST;

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

@@ -33,6 +33,12 @@ struct bnxt_cos2bw_cfg {
 	u8			unused;
 };
 
+struct bnxt_dscp2pri_entry {
+	u8	dscp;
+	u8	mask;
+	u8	pri;
+};
+
 #define BNXT_LLQ(q_profile)	\
 	((q_profile) ==		\
 	 QUEUE_QPORTCFG_RESP_QUEUE_ID0_SERVICE_PROFILE_LOSSLESS_ROCE)