1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
2 /* Copyright 2020 NXP */
3 
4 #include "dpaa2-eth.h"
5 
6 static int dpaa2_eth_dcbnl_ieee_getpfc(struct net_device *net_dev,
7 				       struct ieee_pfc *pfc)
8 {
9 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
10 
11 	if (!(priv->link_state.options & DPNI_LINK_OPT_PFC_PAUSE))
12 		return 0;
13 
14 	memcpy(pfc, &priv->pfc, sizeof(priv->pfc));
15 	pfc->pfc_cap = dpaa2_eth_tc_count(priv);
16 
17 	return 0;
18 }
19 
20 static inline bool is_prio_enabled(u8 pfc_en, u8 tc)
21 {
22 	return !!(pfc_en & (1 << tc));
23 }
24 
25 static int set_pfc_cn(struct dpaa2_eth_priv *priv, u8 pfc_en)
26 {
27 	struct dpni_congestion_notification_cfg cfg = {0};
28 	int i, err;
29 
30 	cfg.notification_mode = DPNI_CONG_OPT_FLOW_CONTROL;
31 	cfg.units = DPNI_CONGESTION_UNIT_FRAMES;
32 	cfg.message_iova = 0ULL;
33 	cfg.message_ctx = 0ULL;
34 
35 	for (i = 0; i < dpaa2_eth_tc_count(priv); i++) {
36 		if (is_prio_enabled(pfc_en, i)) {
37 			cfg.threshold_entry = DPAA2_ETH_CN_THRESH_ENTRY(priv);
38 			cfg.threshold_exit = DPAA2_ETH_CN_THRESH_EXIT(priv);
39 		} else {
40 			/* For priorities not set in the pfc_en mask, we leave
41 			 * the congestion thresholds at zero, which effectively
42 			 * disables generation of PFC frames for them
43 			 */
44 			cfg.threshold_entry = 0;
45 			cfg.threshold_exit = 0;
46 		}
47 
48 		err = dpni_set_congestion_notification(priv->mc_io, 0,
49 						       priv->mc_token,
50 						       DPNI_QUEUE_RX, i, &cfg);
51 		if (err) {
52 			netdev_err(priv->net_dev,
53 				   "dpni_set_congestion_notification failed\n");
54 			return err;
55 		}
56 	}
57 
58 	return 0;
59 }
60 
61 static int dpaa2_eth_dcbnl_ieee_setpfc(struct net_device *net_dev,
62 				       struct ieee_pfc *pfc)
63 {
64 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
65 	struct dpni_link_cfg link_cfg = {0};
66 	bool tx_pause;
67 	int err;
68 
69 	if (pfc->mbc || pfc->delay)
70 		return -EOPNOTSUPP;
71 
72 	/* If same PFC enabled mask, nothing to do */
73 	if (priv->pfc.pfc_en == pfc->pfc_en)
74 		return 0;
75 
76 	/* We allow PFC configuration even if it won't have any effect until
77 	 * general pause frames are enabled
78 	 */
79 	tx_pause = dpaa2_eth_tx_pause_enabled(priv->link_state.options);
80 	if (!dpaa2_eth_rx_pause_enabled(priv->link_state.options) || !tx_pause)
81 		netdev_warn(net_dev, "Pause support must be enabled in order for PFC to work!\n");
82 
83 	link_cfg.rate = priv->link_state.rate;
84 	link_cfg.options = priv->link_state.options;
85 	if (pfc->pfc_en)
86 		link_cfg.options |= DPNI_LINK_OPT_PFC_PAUSE;
87 	else
88 		link_cfg.options &= ~DPNI_LINK_OPT_PFC_PAUSE;
89 	err = dpni_set_link_cfg(priv->mc_io, 0, priv->mc_token, &link_cfg);
90 	if (err) {
91 		netdev_err(net_dev, "dpni_set_link_cfg failed\n");
92 		return err;
93 	}
94 
95 	/* Configure congestion notifications for the enabled priorities */
96 	err = set_pfc_cn(priv, pfc->pfc_en);
97 	if (err)
98 		return err;
99 
100 	memcpy(&priv->pfc, pfc, sizeof(priv->pfc));
101 	priv->pfc_enabled = !!pfc->pfc_en;
102 
103 	dpaa2_eth_set_rx_taildrop(priv, tx_pause, priv->pfc_enabled);
104 
105 	return 0;
106 }
107 
108 static u8 dpaa2_eth_dcbnl_getdcbx(struct net_device *net_dev)
109 {
110 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
111 
112 	return priv->dcbx_mode;
113 }
114 
115 static u8 dpaa2_eth_dcbnl_setdcbx(struct net_device *net_dev, u8 mode)
116 {
117 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
118 
119 	return (mode != (priv->dcbx_mode)) ? 1 : 0;
120 }
121 
122 static u8 dpaa2_eth_dcbnl_getcap(struct net_device *net_dev, int capid, u8 *cap)
123 {
124 	struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
125 
126 	switch (capid) {
127 	case DCB_CAP_ATTR_PFC:
128 		*cap = true;
129 		break;
130 	case DCB_CAP_ATTR_PFC_TCS:
131 		*cap = 1 << (dpaa2_eth_tc_count(priv) - 1);
132 		break;
133 	case DCB_CAP_ATTR_DCBX:
134 		*cap = priv->dcbx_mode;
135 		break;
136 	default:
137 		*cap = false;
138 		break;
139 	}
140 
141 	return 0;
142 }
143 
144 const struct dcbnl_rtnl_ops dpaa2_eth_dcbnl_ops = {
145 	.ieee_getpfc	= dpaa2_eth_dcbnl_ieee_getpfc,
146 	.ieee_setpfc	= dpaa2_eth_dcbnl_ieee_setpfc,
147 	.getdcbx	= dpaa2_eth_dcbnl_getdcbx,
148 	.setdcbx	= dpaa2_eth_dcbnl_setdcbx,
149 	.getcap		= dpaa2_eth_dcbnl_getcap,
150 };
151