nfp: add DCB IEEE support

Add basic DCB IEEE support. This includes support for ETS, max-rate,
and DSCP to user priority mapping.

DCB may be configured using iproute2's dcb command.
Example usage:
  dcb ets set dev $dev tc-tsa 0:ets 1:ets 2:ets 3:ets 4:ets 5:ets \
    6:ets 7:ets tc-bw 0:0 1:80 2:0 3:0 4:0 5:0 6:20 7:0
  dcb maxrate set dev $dev tc-maxrate 1:1000bit

And DCB configuration can be shown using:
  dcb ets show dev $dev
  dcb maxrate show dev $dev
Signed-off-by: Bin Chen <bin.chen@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230112121102.469739-1-simon.horman@corigine.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/netronome/nfp/Makefile

@@ -83,3 +83,5 @@ endif
 nfp-$(CONFIG_NFP_NET_IPSEC) += crypto/ipsec.o nfd3/ipsec.o
 
 nfp-$(CONFIG_NFP_DEBUG) += nfp_net_debugfs.o
+
+nfp-$(CONFIG_DCB) += nic/dcb.o

drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h

@@ -413,6 +413,7 @@
 #define NFP_NET_CFG_MBOX_CMD_IPSEC 3
 #define NFP_NET_CFG_MBOX_CMD_PCI_DSCP_PRIOMAP_SET	5
 #define NFP_NET_CFG_MBOX_CMD_TLV_CMSG			6
+#define NFP_NET_CFG_MBOX_CMD_DCB_UPDATE			7
 
 #define NFP_NET_CFG_MBOX_CMD_MULTICAST_ADD		8
 #define NFP_NET_CFG_MBOX_CMD_MULTICAST_DEL		9

drivers/net/ethernet/netronome/nfp/nic/main.c

@@ -5,6 +5,8 @@
 #include "../nfpcore/nfp_nsp.h"
 #include "../nfp_app.h"
 #include "../nfp_main.h"
+#include "../nfp_net.h"
+#include "main.h"
 
 static int nfp_nic_init(struct nfp_app *app)
 {
@@ -28,13 +30,46 @@ static void nfp_nic_sriov_disable(struct nfp_app *app)
 {
 }
 
+static int nfp_nic_vnic_init(struct nfp_app *app, struct nfp_net *nn)
+{
+	nfp_nic_dcb_init(nn);
+
+	return 0;
+}
+
+static int nfp_nic_vnic_alloc(struct nfp_app *app, struct nfp_net *nn,
+			      unsigned int id)
+{
+	struct nfp_app_nic_private *app_pri = nn->app_priv;
+	int err;
+
+	err = nfp_app_nic_vnic_alloc(app, nn, id);
+	if (err)
+		return err;
+
+	if (sizeof(*app_pri)) {
+		nn->app_priv = kzalloc(sizeof(*app_pri), GFP_KERNEL);
+		if (!nn->app_priv)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void nfp_nic_vnic_free(struct nfp_app *app, struct nfp_net *nn)
+{
+	kfree(nn->app_priv);
+}
+
 const struct nfp_app_type app_nic = {
 	.id		= NFP_APP_CORE_NIC,
 	.name		= "nic",
 
 	.init		= nfp_nic_init,
-	.vnic_alloc	= nfp_app_nic_vnic_alloc,
-
+	.vnic_alloc	= nfp_nic_vnic_alloc,
+	.vnic_free	= nfp_nic_vnic_free,
 	.sriov_enable	= nfp_nic_sriov_enable,
 	.sriov_disable	= nfp_nic_sriov_disable,
+
+	.vnic_init      = nfp_nic_vnic_init,
 };

drivers/net/ethernet/netronome/nfp/nic/main.h

+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/* Copyright (C) 2023 Corigine, Inc. */
+
+#ifndef __NFP_NIC_H__
+#define __NFP_NIC_H__ 1
+
+#include <linux/netdevice.h>
+
+#ifdef CONFIG_DCB
+/* DCB feature definitions */
+#define NFP_NET_MAX_DSCP	4
+#define NFP_NET_MAX_TC		IEEE_8021QAZ_MAX_TCS
+#define NFP_NET_MAX_PRIO	8
+#define NFP_DCB_CFG_STRIDE	256
+
+struct nfp_dcb {
+	u8 dscp2prio[NFP_NET_MAX_DSCP];
+	u8 prio2tc[NFP_NET_MAX_PRIO];
+	u8 tc2idx[IEEE_8021QAZ_MAX_TCS];
+	u64 tc_maxrate[IEEE_8021QAZ_MAX_TCS];
+	u8 tc_tx_pct[IEEE_8021QAZ_MAX_TCS];
+	u8 tc_tsa[IEEE_8021QAZ_MAX_TCS];
+	u8 dscp_cnt;
+	u8 trust_status;
+	bool rate_init;
+	bool ets_init;
+
+	struct nfp_cpp_area *dcbcfg_tbl_area;
+	u8 __iomem *dcbcfg_tbl;
+	u32 cfg_offset;
+};
+
+int nfp_nic_dcb_init(struct nfp_net *nn);
+void nfp_nic_dcb_clean(struct nfp_net *nn);
+#else
+static inline int nfp_nic_dcb_init(struct nfp_net *nn) {return 0; }
+static inline void nfp_nic_dcb_clean(struct nfp_net *nn) {}
+#endif
+
+struct nfp_app_nic_private {
+#ifdef CONFIG_DCB
+	struct nfp_dcb dcb;
+#endif
+};
+
+#endif