mlxsw: spectrum_nve: Implement VxLAN operations

The common NVE core expects each encapsulation type to implement a
certain set of operations that are specific to this type and the
currently used ASIC. These operations include things such as the ability
to determine whether a certain NVE configuration can be offloaded and
ASIC-specific initialization for this type.

Implement these operations for VxLAN on the Spectrum ASIC. Spectrum-2
support will be added by a future patchset.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_nve_vxlan.c

@@ -3,30 +3,216 @@
 
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
+#include <linux/random.h>
+#include <net/vxlan.h>
 
+#include "reg.h"
 #include "spectrum_nve.h"
 
+/* Eth (18B) | IPv6 (40B) | UDP (8B) | VxLAN (8B) | Eth (14B) | IPv6 (40B)
+ *
+ * In the worst case - where we have a VLAN tag on the outer Ethernet
+ * header and IPv6 in overlay and underlay - we need to parse 128 bytes
+ */
+#define MLXSW_SP_NVE_VXLAN_PARSING_DEPTH 128
+#define MLXSW_SP_NVE_DEFAULT_PARSING_DEPTH 96
+
+#define MLXSW_SP_NVE_VXLAN_SUPPORTED_FLAGS	VXLAN_F_UDP_ZERO_CSUM_TX
+
 static bool mlxsw_sp1_nve_vxlan_can_offload(const struct mlxsw_sp_nve *nve,
 					    const struct net_device *dev,
 					    struct netlink_ext_ack *extack)
 {
-	return false;
+	struct vxlan_dev *vxlan = netdev_priv(dev);
+	struct vxlan_config *cfg = &vxlan->cfg;
+
+	if (cfg->saddr.sa.sa_family != AF_INET) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Only IPv4 underlay is supported");
+		return false;
+	}
+
+	if (vxlan_addr_multicast(&cfg->remote_ip)) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Multicast destination IP is not supported");
+		return false;
+	}
+
+	if (vxlan_addr_any(&cfg->saddr)) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Source address must be specified");
+		return false;
+	}
+
+	if (cfg->remote_ifindex) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Local interface is not supported");
+		return false;
+	}
+
+	if (cfg->port_min || cfg->port_max) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Only default UDP source port range is supported");
+		return false;
+	}
+
+	if (cfg->tos != 1) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: TOS must be configured to inherit");
+		return false;
+	}
+
+	if (cfg->flags & VXLAN_F_TTL_INHERIT) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: TTL must not be configured to inherit");
+		return false;
+	}
+
+	if (cfg->flags & VXLAN_F_LEARN) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Learning is not supported");
+		return false;
+	}
+
+	if (!(cfg->flags & VXLAN_F_UDP_ZERO_CSUM_TX)) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: UDP checksum is not supported");
+		return false;
+	}
+
+	if (cfg->flags & ~MLXSW_SP_NVE_VXLAN_SUPPORTED_FLAGS) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Unsupported flag");
+		return false;
+	}
+
+	if (cfg->ttl == 0) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: TTL must not be configured to 0");
+		return false;
+	}
+
+	if (cfg->label != 0) {
+		NL_SET_ERR_MSG_MOD(extack, "VxLAN: Flow label must be configured to 0");
+		return false;
+	}
+
+	return true;
 }
 
 static void mlxsw_sp_nve_vxlan_config(const struct mlxsw_sp_nve *nve,
 				      const struct net_device *dev,
 				      struct mlxsw_sp_nve_config *config)
 {
+	struct vxlan_dev *vxlan = netdev_priv(dev);
+	struct vxlan_config *cfg = &vxlan->cfg;
+
+	config->type = MLXSW_SP_NVE_TYPE_VXLAN;
+	config->ttl = cfg->ttl;
+	config->flowlabel = cfg->label;
+	config->learning_en = cfg->flags & VXLAN_F_LEARN ? 1 : 0;
+	config->ul_tb_id = RT_TABLE_MAIN;
+	config->ul_proto = MLXSW_SP_L3_PROTO_IPV4;
+	config->ul_sip.addr4 = cfg->saddr.sin.sin_addr.s_addr;
+	config->udp_dport = cfg->dst_port;
+}
+
+static int mlxsw_sp_nve_parsing_set(struct mlxsw_sp *mlxsw_sp,
+				    unsigned int parsing_depth,
+				    __be16 udp_dport)
+{
+	char mprs_pl[MLXSW_REG_MPRS_LEN];
+
+	mlxsw_reg_mprs_pack(mprs_pl, parsing_depth, be16_to_cpu(udp_dport));
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mprs), mprs_pl);
+}
+
+static int
+mlxsw_sp1_nve_vxlan_config_set(struct mlxsw_sp *mlxsw_sp,
+			       const struct mlxsw_sp_nve_config *config)
+{
+	char tngcr_pl[MLXSW_REG_TNGCR_LEN];
+	u16 ul_vr_id;
+	u8 udp_sport;
+	int err;
+
+	err = mlxsw_sp_router_tb_id_vr_id(mlxsw_sp, config->ul_tb_id,
+					  &ul_vr_id);
+	if (err)
+		return err;
+
+	mlxsw_reg_tngcr_pack(tngcr_pl, MLXSW_REG_TNGCR_TYPE_VXLAN, true,
+			     config->ttl);
+	/* VxLAN driver's default UDP source port range is 32768 (0x8000)
+	 * to 60999 (0xee47). Set the upper 8 bits of the UDP source port
+	 * to a random number between 0x80 and 0xee
+	 */
+	get_random_bytes(&udp_sport, sizeof(udp_sport));
+	udp_sport = (udp_sport % (0xee - 0x80 + 1)) + 0x80;
+	mlxsw_reg_tngcr_nve_udp_sport_prefix_set(tngcr_pl, udp_sport);
+	mlxsw_reg_tngcr_learn_enable_set(tngcr_pl, config->learning_en);
+	mlxsw_reg_tngcr_underlay_virtual_router_set(tngcr_pl, ul_vr_id);
+	mlxsw_reg_tngcr_usipv4_set(tngcr_pl, be32_to_cpu(config->ul_sip.addr4));
+
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tngcr), tngcr_pl);
+}
+
+static void mlxsw_sp1_nve_vxlan_config_clear(struct mlxsw_sp *mlxsw_sp)
+{
+	char tngcr_pl[MLXSW_REG_TNGCR_LEN];
+
+	mlxsw_reg_tngcr_pack(tngcr_pl, MLXSW_REG_TNGCR_TYPE_VXLAN, false, 0);
+
+	mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tngcr), tngcr_pl);
+}
+
+static int mlxsw_sp1_nve_vxlan_rtdp_set(struct mlxsw_sp *mlxsw_sp,
+					unsigned int tunnel_index)
+{
+	char rtdp_pl[MLXSW_REG_RTDP_LEN];
+
+	mlxsw_reg_rtdp_pack(rtdp_pl, MLXSW_REG_RTDP_TYPE_NVE, tunnel_index);
+
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(rtdp), rtdp_pl);
 }
 
 static int mlxsw_sp1_nve_vxlan_init(struct mlxsw_sp_nve *nve,
 				    const struct mlxsw_sp_nve_config *config)
 {
-	return -EOPNOTSUPP;
+	struct mlxsw_sp *mlxsw_sp = nve->mlxsw_sp;
+	int err;
+
+	err = mlxsw_sp_nve_parsing_set(mlxsw_sp,
+				       MLXSW_SP_NVE_VXLAN_PARSING_DEPTH,
+				       config->udp_dport);
+	if (err)
+		return err;
+
+	err = mlxsw_sp1_nve_vxlan_config_set(mlxsw_sp, config);
+	if (err)
+		goto err_config_set;
+
+	err = mlxsw_sp1_nve_vxlan_rtdp_set(mlxsw_sp, nve->tunnel_index);
+	if (err)
+		goto err_rtdp_set;
+
+	err = mlxsw_sp_router_nve_promote_decap(mlxsw_sp, config->ul_tb_id,
+						config->ul_proto,
+						&config->ul_sip,
+						nve->tunnel_index);
+	if (err)
+		goto err_promote_decap;
+
+	return 0;
+
+err_promote_decap:
+err_rtdp_set:
+	mlxsw_sp1_nve_vxlan_config_clear(mlxsw_sp);
+err_config_set:
+	mlxsw_sp_nve_parsing_set(mlxsw_sp, MLXSW_SP_NVE_DEFAULT_PARSING_DEPTH,
+				 config->udp_dport);
+	return err;
 }
 
 static void mlxsw_sp1_nve_vxlan_fini(struct mlxsw_sp_nve *nve)
 {
+	struct mlxsw_sp_nve_config *config = &nve->config;
+	struct mlxsw_sp *mlxsw_sp = nve->mlxsw_sp;
+
+	mlxsw_sp_router_nve_demote_decap(mlxsw_sp, config->ul_tb_id,
+					 config->ul_proto, &config->ul_sip);
+	mlxsw_sp1_nve_vxlan_config_clear(mlxsw_sp);
+	mlxsw_sp_nve_parsing_set(mlxsw_sp, MLXSW_SP_NVE_DEFAULT_PARSING_DEPTH,
+				 config->udp_dport);
 }
 
 const struct mlxsw_sp_nve_ops mlxsw_sp1_nve_vxlan_ops = {