linux/drivers/net/ethernet/amd/xgbe/xgbe-dcb.c

// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause)
/*
 * Copyright (c) 2014-2025, Advanced Micro Devices, Inc.
 * Copyright (c) 2014, Synopsys, Inc.
 * All rights reserved
 */

#include <linux/netdevice.h>
#include <net/dcbnl.h>

#include "xgbe.h"
#include "xgbe-common.h"

static int xgbe_dcb_ieee_getets(struct net_device *netdev,
				struct ieee_ets *ets)
{
	struct xgbe_prv_data *pdata = netdev_priv(netdev);

	/* Set number of supported traffic classes */
	ets->ets_cap = pdata->hw_feat.tc_cnt;

	if (pdata->ets) {
		ets->cbs = pdata->ets->cbs;
		memcpy(ets->tc_tx_bw, pdata->ets->tc_tx_bw,
		       sizeof(ets->tc_tx_bw));
		memcpy(ets->tc_tsa, pdata->ets->tc_tsa,
		       sizeof(ets->tc_tsa));
		memcpy(ets->prio_tc, pdata->ets->prio_tc,
		       sizeof(ets->prio_tc));
	}

	return 0;
}

static int xgbe_dcb_ieee_setets(struct net_device *netdev,
				struct ieee_ets *ets)
{
	struct xgbe_prv_data *pdata = netdev_priv(netdev);
	unsigned int i, tc_ets, tc_ets_weight;
	u8 max_tc = 0;

	tc_ets = 0;
	tc_ets_weight = 0;
	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
		netif_dbg(pdata, drv, netdev,
			  "TC%u: tx_bw=%hhu, rx_bw=%hhu, tsa=%hhu\n", i,
			  ets->tc_tx_bw[i], ets->tc_rx_bw[i],
			  ets->tc_tsa[i]);
		netif_dbg(pdata, drv, netdev, "PRIO%u: TC=%hhu\n", i,
			  ets->prio_tc[i]);

		max_tc = max_t(u8, max_tc, ets->prio_tc[i]);
		if ((ets->tc_tx_bw[i] || ets->tc_tsa[i]))
			max_tc = max_t(u8, max_tc, i);

		switch (ets->tc_tsa[i]) {
		case IEEE_8021QAZ_TSA_STRICT:
			break;
		case IEEE_8021QAZ_TSA_ETS:
			tc_ets = 1;
			tc_ets_weight += ets->tc_tx_bw[i];
			break;
		default:
			netif_err(pdata, drv, netdev,
				  "unsupported TSA algorithm (%hhu)\n",
				  ets->tc_tsa[i]);
			return -EINVAL;
		}
	}

	/* Check maximum traffic class requested */
	if (max_tc >= pdata->hw_feat.tc_cnt) {
		netif_err(pdata, drv, netdev,
			  "exceeded number of supported traffic classes\n");
		return -EINVAL;
	}

	/* Weights must add up to 100% */
	if (tc_ets && (tc_ets_weight != 100)) {
		netif_err(pdata, drv, netdev,
			  "sum of ETS algorithm weights is not 100 (%u)\n",
			  tc_ets_weight);
		return -EINVAL;
	}

	if (!pdata->ets) {
		pdata->ets = devm_kzalloc(pdata->dev, sizeof(*pdata->ets),
					  GFP_KERNEL);
		if (!pdata->ets)
			return -ENOMEM;
	}

	pdata->num_tcs = max_tc + 1;
	memcpy(pdata->ets, ets, sizeof(*pdata->ets));

	pdata->hw_if.config_dcb_tc(pdata);

	return 0;
}

static int xgbe_dcb_ieee_getpfc(struct net_device *netdev,
				struct ieee_pfc *pfc)
{
	struct xgbe_prv_data *pdata = netdev_priv(netdev);

	/* Set number of supported PFC traffic classes */
	pfc->pfc_cap = pdata->hw_feat.tc_cnt;

	if (pdata->pfc) {
		pfc->pfc_en = pdata->pfc->pfc_en;
		pfc->mbc = pdata->pfc->mbc;
		pfc->delay = pdata->pfc->delay;
	}

	return 0;
}

static int xgbe_dcb_ieee_setpfc(struct net_device *netdev,
				struct ieee_pfc *pfc)
{
	struct xgbe_prv_data *pdata = netdev_priv(netdev);

	netif_dbg(pdata, drv, netdev,
		  "cap=%d, en=%#x, mbc=%d, delay=%d\n",
		  pfc->pfc_cap, pfc->pfc_en, pfc->mbc, pfc->delay);

	/* Check PFC for supported number of traffic classes */
	if (pfc->pfc_en & ~((1 << pdata->hw_feat.tc_cnt) - 1)) {
		netif_err(pdata, drv, netdev,
			  "PFC requested for unsupported traffic class\n");
		return -EINVAL;
	}

	if (!pdata->pfc) {
		pdata->pfc = devm_kzalloc(pdata->dev, sizeof(*pdata->pfc),
					  GFP_KERNEL);
		if (!pdata->pfc)
			return -ENOMEM;
	}

	memcpy(pdata->pfc, pfc, sizeof(*pdata->pfc));

	pdata->hw_if.config_dcb_pfc(pdata);

	return 0;
}

static u8 xgbe_dcb_getdcbx(struct net_device *netdev)
{
	return DCB_CAP_DCBX_HOST | DCB_CAP_DCBX_VER_IEEE;
}

static u8 xgbe_dcb_setdcbx(struct net_device *netdev, u8 dcbx)
{
	struct xgbe_prv_data *pdata = netdev_priv(netdev);
	u8 support = xgbe_dcb_getdcbx(netdev);

	netif_dbg(pdata, drv, netdev, "DCBX=%#hhx\n", dcbx);

	if (dcbx & ~support)
		return 1;

	if ((dcbx & support) != support)
		return 1;

	return 0;
}

static const struct dcbnl_rtnl_ops xgbe_dcbnl_ops = {
	/* IEEE 802.1Qaz std */
	.ieee_getets = xgbe_dcb_ieee_getets,
	.ieee_setets = xgbe_dcb_ieee_setets,
	.ieee_getpfc = xgbe_dcb_ieee_getpfc,
	.ieee_setpfc = xgbe_dcb_ieee_setpfc,

	/* DCBX configuration */
	.getdcbx     = xgbe_dcb_getdcbx,
	.setdcbx     = xgbe_dcb_setdcbx,
};

const struct dcbnl_rtnl_ops *xgbe_get_dcbnl_ops(void)
{
	return &xgbe_dcbnl_ops;
}