[PATCH net-next 2/6] net: microchip: sparx5: Add support for TC flower ARP dissector

[Steen Hegelund]

This add support for Sparx5 for dissecting TC ARP flower filter keys and
sets up the Sparx5 IS2 VCAP to generate the ARP keyset for ARP frames.

Signed-off-by: Steen Hegelund <steen.hegelund@xxxxxxxxxxxxx>
---
 .../microchip/sparx5/sparx5_tc_flower.c       | 76 +++++++++++++++++++
 .../microchip/sparx5/sparx5_vcap_impl.c       |  2 +-
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
index 7b364f6b4546..b76b8fc567bb 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
@@ -26,10 +26,24 @@ struct sparx5_tc_flower_parse_usage {
  */
 static u16 sparx5_tc_known_etypes[] = {
 	ETH_P_ALL,
+	ETH_P_ARP,
 	ETH_P_IP,
 	ETH_P_IPV6,
 };
 
+enum sparx5_is2_arp_opcode {
+	SPX5_IS2_ARP_REQUEST,
+	SPX5_IS2_ARP_REPLY,
+	SPX5_IS2_RARP_REQUEST,
+	SPX5_IS2_RARP_REPLY,
+};
+
+enum tc_arp_opcode {
+	TC_ARP_OP_RESERVED,
+	TC_ARP_OP_REQUEST,
+	TC_ARP_OP_REPLY,
+};
+
 static bool sparx5_tc_is_known_etype(u16 etype)
 {
 	int idx;
@@ -404,6 +418,67 @@ sparx5_tc_flower_handler_tcp_usage(struct sparx5_tc_flower_parse_usage *st)
 	return err;
 }
 
+static int
+sparx5_tc_flower_handler_arp_usage(struct sparx5_tc_flower_parse_usage *st)
+{
+	struct flow_match_arp mt;
+	u16 value, mask;
+	u32 ipval, ipmsk;
+	int err;
+
+	flow_rule_match_arp(st->frule, &mt);
+
+	if (mt.mask->op) {
+		mask = 0x3;
+		if (st->l3_proto == ETH_P_ARP) {
+			value = mt.key->op == TC_ARP_OP_REQUEST ?
+					SPX5_IS2_ARP_REQUEST :
+					SPX5_IS2_ARP_REPLY;
+		} else { /* RARP */
+			value = mt.key->op == TC_ARP_OP_REQUEST ?
+					SPX5_IS2_RARP_REQUEST :
+					SPX5_IS2_RARP_REPLY;
+		}
+		err = vcap_rule_add_key_u32(st->vrule, VCAP_KF_ARP_OPCODE,
+					    value, mask);
+		if (err)
+			goto out;
+	}
+
+	/* The IS2 ARP keyset does not support ARP hardware addresses */
+	if (!is_zero_ether_addr(mt.mask->sha) ||
+	    !is_zero_ether_addr(mt.mask->tha))
+		goto out;
+
+	if (mt.mask->sip) {
+		ipval = be32_to_cpu((__force __be32)mt.key->sip);
+		ipmsk = be32_to_cpu((__force __be32)mt.mask->sip);
+
+		err = vcap_rule_add_key_u32(st->vrule, VCAP_KF_L3_IP4_SIP,
+					    ipval, ipmsk);
+		if (err)
+			goto out;
+	}
+
+	if (mt.mask->tip) {
+		ipval = be32_to_cpu((__force __be32)mt.key->tip);
+		ipmsk = be32_to_cpu((__force __be32)mt.mask->tip);
+
+		err = vcap_rule_add_key_u32(st->vrule, VCAP_KF_L3_IP4_DIP,
+					    ipval, ipmsk);
+		if (err)
+			goto out;
+	}
+
+	st->used_keys |= BIT(FLOW_DISSECTOR_KEY_ARP);
+
+	return err;
+
+out:
+	NL_SET_ERR_MSG_MOD(st->fco->common.extack, "arp parse error");
+	return err;
+}
+
 static int
 sparx5_tc_flower_handler_ip_usage(struct sparx5_tc_flower_parse_usage *st)
 {
@@ -438,6 +513,7 @@ static int (*sparx5_tc_flower_usage_handlers[])(struct sparx5_tc_flower_parse_us
 	[FLOW_DISSECTOR_KEY_BASIC] = sparx5_tc_flower_handler_basic_usage,
 	[FLOW_DISSECTOR_KEY_VLAN] = sparx5_tc_flower_handler_vlan_usage,
 	[FLOW_DISSECTOR_KEY_TCP] = sparx5_tc_flower_handler_tcp_usage,
+	[FLOW_DISSECTOR_KEY_ARP] = sparx5_tc_flower_handler_arp_usage,
 	[FLOW_DISSECTOR_KEY_IP] = sparx5_tc_flower_handler_ip_usage,
 };
 
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c b/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
index 10bc56cd0045..db73e2b19dc5 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_vcap_impl.c
@@ -540,7 +540,7 @@ static void sparx5_vcap_port_key_selection(struct sparx5 *sparx5,
 				 VCAP_IS2_PS_IPV4_UC_IP4_TCP_UDP_OTHER,
 				 VCAP_IS2_PS_IPV6_MC_IP_7TUPLE,
 				 VCAP_IS2_PS_IPV6_UC_IP_7TUPLE,
-				 VCAP_IS2_PS_ARP_MAC_ETYPE);
+				 VCAP_IS2_PS_ARP_ARP);
 	for (lookup = 0; lookup < admin->lookups; ++lookup) {
 		for (portno = 0; portno < SPX5_PORTS; ++portno) {
 			spx5_wr(keysel, sparx5,
-- 
2.38.1