net: atlantic: MACSec offload skeleton

This patch adds basic functionality for MACSec offloading for Atlantic
NICs.

MACSec offloading functionality is enabled if network card has
appropriate FW that has MACSec offloading enabled in config.

Actual functionality (ingress, egress, etc) will be added in follow-up
patches.

Signed-off-by: Dmitry Bogdanov <dbogdanov@marvell.com>
Signed-off-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 174 insertions, 0 deletions

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_macsec.c b/drivers/net/ethernet/aquantia/atlantic/aq_macsec.c
new file mode 100644
index 000000000000..e9d8852bfbe0
--- /dev/null
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_macsec.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Atlantic Network Driver
+ * Copyright (C) 2020 Marvell International Ltd.
+ */
+
+#include "aq_macsec.h"
+#include "aq_nic.h"
+#include <linux/rtnetlink.h>
+
+static int aq_mdo_dev_open(struct macsec_context *ctx)
+{
+	return 0;
+}
+
+static int aq_mdo_dev_stop(struct macsec_context *ctx)
+{
+	return 0;
+}
+
+static int aq_mdo_add_secy(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_upd_secy(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_del_secy(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_add_txsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_upd_txsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_del_txsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_add_rxsc(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_upd_rxsc(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_del_rxsc(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_add_rxsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_upd_rxsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static int aq_mdo_del_rxsa(struct macsec_context *ctx)
+{
+	return -EOPNOTSUPP;
+}
+
+static void aq_check_txsa_expiration(struct aq_nic_s *nic)
+{
+}
+
+const struct macsec_ops aq_macsec_ops = {
+	.mdo_dev_open = aq_mdo_dev_open,
+	.mdo_dev_stop = aq_mdo_dev_stop,
+	.mdo_add_secy = aq_mdo_add_secy,
+	.mdo_upd_secy = aq_mdo_upd_secy,
+	.mdo_del_secy = aq_mdo_del_secy,
+	.mdo_add_rxsc = aq_mdo_add_rxsc,
+	.mdo_upd_rxsc = aq_mdo_upd_rxsc,
+	.mdo_del_rxsc = aq_mdo_del_rxsc,
+	.mdo_add_rxsa = aq_mdo_add_rxsa,
+	.mdo_upd_rxsa = aq_mdo_upd_rxsa,
+	.mdo_del_rxsa = aq_mdo_del_rxsa,
+	.mdo_add_txsa = aq_mdo_add_txsa,
+	.mdo_upd_txsa = aq_mdo_upd_txsa,
+	.mdo_del_txsa = aq_mdo_del_txsa,
+};
+
+int aq_macsec_init(struct aq_nic_s *nic)
+{
+	struct aq_macsec_cfg *cfg;
+	u32 caps_lo;
+
+	if (!nic->aq_fw_ops->get_link_capabilities)
+		return 0;
+
+	caps_lo = nic->aq_fw_ops->get_link_capabilities(nic->aq_hw);
+
+	if (!(caps_lo & BIT(CAPS_LO_MACSEC)))
+		return 0;
+
+	nic->macsec_cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+	if (!nic->macsec_cfg)
+		return -ENOMEM;
+
+	nic->ndev->features |= NETIF_F_HW_MACSEC;
+	nic->ndev->macsec_ops = &aq_macsec_ops;
+
+	return 0;
+}
+
+void aq_macsec_free(struct aq_nic_s *nic)
+{
+	kfree(nic->macsec_cfg);
+	nic->macsec_cfg = NULL;
+}
+
+int aq_macsec_enable(struct aq_nic_s *nic)
+{
+	struct macsec_msg_fw_response resp = { 0 };
+	struct macsec_msg_fw_request msg = { 0 };
+	struct aq_hw_s *hw = nic->aq_hw;
+	int ret = 0;
+
+	if (!nic->macsec_cfg)
+		return 0;
+
+	rtnl_lock();
+
+	if (nic->aq_fw_ops->send_macsec_req) {
+		struct macsec_cfg_request cfg = { 0 };
+
+		cfg.enabled = 1;
+		cfg.egress_threshold = 0xffffffff;
+		cfg.ingress_threshold = 0xffffffff;
+		cfg.interrupts_enabled = 1;
+
+		msg.msg_type = macsec_cfg_msg;
+		msg.cfg = cfg;
+
+		ret = nic->aq_fw_ops->send_macsec_req(hw, &msg, &resp);
+		if (ret)
+			goto unlock;
+	}
+
+unlock:
+	rtnl_unlock();
+	return ret;
+}
+
+void aq_macsec_work(struct aq_nic_s *nic)
+{
+	if (!nic->macsec_cfg)
+		return;
+
+	if (!netif_carrier_ok(nic->ndev))
+		return;
+
+	rtnl_lock();
+	aq_check_txsa_expiration(nic);
+	rtnl_unlock();
+}