octeontx2-pf: PFC config support with DCBx

Data centric bridging designed to eliminate packet loss due to
queue overflow by adding enhancements to ethernet network such as
proprity flow control etc. This patch adds support for management
of Priority flow control(PFC) on Octeontx2 and CN10K interfaces.

To enable PFC for all priorities
	dcb pfc set dev eth0 prio-pfc all:on/off

To enable PFC on selected priorites
	dcb pfc set dev eth0 prio-pfc 0:on/off 1:on/off ..7:on/off

With the ntuple commands user can map Priority to receive queues.
On queue overflow NIX will assert backpressure such that PFC pause frames
are genarated with mapped priority.

To map priority 7 to Queue 1
ethtool -U eth0 flow-type ether dst xx:xx:xx:xx:xx:xx vlan 0xe00a
m 0x1fff  queue 1

Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 43 insertions, 7 deletions

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
index 77a13fb555fb..54f235c216a9 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
@@ -21,8 +21,10 @@ struct otx2_flow {
 	u16 entry;
 	bool is_vf;
 	u8 rss_ctx_id;
+#define DMAC_FILTER_RULE		BIT(0)
+#define PFC_FLOWCTRL_RULE		BIT(1)
+	u16 rule_type;
 	int vf;
-	bool dmac_filter;
 };
 
 enum dmac_req {
@@ -899,6 +901,9 @@ static int otx2_is_flow_rule_dmacfilter(struct otx2_nic *pfvf,
 static int otx2_add_flow_msg(struct otx2_nic *pfvf, struct otx2_flow *flow)
 {
 	u64 ring_cookie = flow->flow_spec.ring_cookie;
+#ifdef CONFIG_DCB
+	int vlan_prio, qidx, pfc_rule = 0;
+#endif
 	struct npc_install_flow_req *req;
 	int err, vf = 0;
 
@@ -940,6 +945,24 @@ static int otx2_add_flow_msg(struct otx2_nic *pfvf, struct otx2_flow *flow)
 			mutex_unlock(&pfvf->mbox.lock);
 			return -EINVAL;
 		}
+
+#ifdef CONFIG_DCB
+		/* Identify PFC rule if PFC enabled and ntuple rule is vlan */
+		if (!vf && (req->features & BIT_ULL(NPC_OUTER_VID)) &&
+		    pfvf->pfc_en && req->op != NIX_RX_ACTIONOP_RSS) {
+			vlan_prio = ntohs(req->packet.vlan_tci) &
+				    ntohs(req->mask.vlan_tci);
+
+			/* Get the priority */
+			vlan_prio >>= 13;
+			flow->rule_type |= PFC_FLOWCTRL_RULE;
+			/* Check if PFC enabled for this priority */
+			if (pfvf->pfc_en & BIT(vlan_prio)) {
+				pfc_rule = true;
+				qidx = req->index;
+			}
+		}
+#endif
 	}
 
 	/* ethtool ring_cookie has (VF + 1) for VF */
@@ -951,6 +974,12 @@ static int otx2_add_flow_msg(struct otx2_nic *pfvf, struct otx2_flow *flow)
 
 	/* Send message to AF */
 	err = otx2_sync_mbox_msg(&pfvf->mbox);
+
+#ifdef CONFIG_DCB
+	if (!err && pfc_rule)
+		otx2_update_bpid_in_rqctx(pfvf, vlan_prio, qidx, true);
+#endif
+
 	mutex_unlock(&pfvf->mbox.lock);
 	return err;
 }
@@ -966,7 +995,7 @@ static int otx2_add_flow_with_pfmac(struct otx2_nic *pfvf,
 		return -ENOMEM;
 
 	pf_mac->entry = 0;
-	pf_mac->dmac_filter = true;
+	pf_mac->rule_type |= DMAC_FILTER_RULE;
 	pf_mac->location = pfvf->flow_cfg->max_flows;
 	memcpy(&pf_mac->flow_spec, &flow->flow_spec,
 	       sizeof(struct ethtool_rx_flow_spec));
@@ -1031,7 +1060,7 @@ int otx2_add_flow(struct otx2_nic *pfvf, struct ethtool_rxnfc *nfc)
 		eth_hdr = &flow->flow_spec.h_u.ether_spec;
 
 		/* Sync dmac filter table with updated fields */
-		if (flow->dmac_filter)
+		if (flow->rule_type & DMAC_FILTER_RULE)
 			return otx2_dmacflt_update(pfvf, eth_hdr->h_dest,
 						   flow->entry);
 
@@ -1052,7 +1081,7 @@ int otx2_add_flow(struct otx2_nic *pfvf, struct ethtool_rxnfc *nfc)
 		if (!test_bit(0, &flow_cfg->dmacflt_bmap))
 			otx2_add_flow_with_pfmac(pfvf, flow);
 
-		flow->dmac_filter = true;
+		flow->rule_type |= DMAC_FILTER_RULE;
 		flow->entry = find_first_zero_bit(&flow_cfg->dmacflt_bmap,
 						  flow_cfg->dmacflt_max_flows);
 		fsp->location = flow_cfg->max_flows + flow->entry;
@@ -1120,7 +1149,7 @@ static void otx2_update_rem_pfmac(struct otx2_nic *pfvf, int req)
 	bool found = false;
 
 	list_for_each_entry(iter, &pfvf->flow_cfg->flow_list, list) {
-		if (iter->dmac_filter && iter->entry == 0) {
+		if ((iter->rule_type & DMAC_FILTER_RULE) && iter->entry == 0) {
 			eth_hdr = &iter->flow_spec.h_u.ether_spec;
 			if (req == DMAC_ADDR_DEL) {
 				otx2_dmacflt_remove(pfvf, eth_hdr->h_dest,
@@ -1156,7 +1185,7 @@ int otx2_remove_flow(struct otx2_nic *pfvf, u32 location)
 	if (!flow)
 		return -ENOENT;
 
-	if (flow->dmac_filter) {
+	if (flow->rule_type & DMAC_FILTER_RULE) {
 		struct ethhdr *eth_hdr = &flow->flow_spec.h_u.ether_spec;
 
 		/* user not allowed to remove dmac filter with interface mac */
@@ -1174,6 +1203,13 @@ int otx2_remove_flow(struct otx2_nic *pfvf, u32 location)
 				  flow_cfg->dmacflt_max_flows) == 1)
 			otx2_update_rem_pfmac(pfvf, DMAC_ADDR_DEL);
 	} else {
+#ifdef CONFIG_DCB
+		if (flow->rule_type & PFC_FLOWCTRL_RULE)
+			otx2_update_bpid_in_rqctx(pfvf, 0,
+						  flow->flow_spec.ring_cookie,
+						  false);
+#endif
+
 		err = otx2_remove_flow_msg(pfvf, flow->entry, false);
 	}
 
@@ -1383,7 +1419,7 @@ void otx2_dmacflt_reinstall_flows(struct otx2_nic *pf)
 	struct ethhdr *eth_hdr;
 
 	list_for_each_entry(iter, &pf->flow_cfg->flow_list, list) {
-		if (iter->dmac_filter) {
+		if (iter->rule_type & DMAC_FILTER_RULE) {
 			eth_hdr = &iter->flow_spec.h_u.ether_spec;
 			otx2_dmacflt_add(pf, eth_hdr->h_dest,
 					 iter->entry);