1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright Gavin Shan, IBM Corporation 2016.
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9 #include <linux/netdevice.h>
10 #include <linux/skbuff.h>
13 #include <net/net_namespace.h>
19 static int ncsi_validate_aen_pkt(struct ncsi_aen_pkt_hdr *h,
20 const unsigned short payload)
25 if (h->common.revision != NCSI_PKT_REVISION)
27 if (ntohs(h->common.length) != payload)
30 /* Validate checksum, which might be zeroes if the
31 * sender doesn't support checksum according to NCSI
34 pchecksum = (__be32 *)((void *)(h + 1) + payload - 4);
35 if (ntohl(*pchecksum) == 0)
38 checksum = ncsi_calculate_checksum((unsigned char *)h,
39 sizeof(*h) + payload - 4);
40 if (*pchecksum != htonl(checksum))
46 static int ncsi_aen_handler_lsc(struct ncsi_dev_priv *ndp,
47 struct ncsi_aen_pkt_hdr *h)
49 struct ncsi_channel *nc, *tmp;
50 struct ncsi_channel_mode *ncm;
51 unsigned long old_data, data;
52 struct ncsi_aen_lsc_pkt *lsc;
53 struct ncsi_package *np;
54 bool had_link, has_link;
59 /* Find the NCSI channel */
60 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
64 /* Update the link status */
65 lsc = (struct ncsi_aen_lsc_pkt *)h;
67 spin_lock_irqsave(&nc->lock, flags);
68 ncm = &nc->modes[NCSI_MODE_LINK];
69 old_data = ncm->data[2];
70 data = ntohl(lsc->status);
72 ncm->data[4] = ntohl(lsc->oem_status);
74 had_link = !!(old_data & 0x1);
75 has_link = !!(data & 0x1);
77 netdev_dbg(ndp->ndev.dev, "NCSI: LSC AEN - channel %u state %s\n",
78 nc->id, data & 0x1 ? "up" : "down");
80 chained = !list_empty(&nc->link);
82 spin_unlock_irqrestore(&nc->lock, flags);
84 if (state == NCSI_CHANNEL_INACTIVE)
85 netdev_warn(ndp->ndev.dev,
86 "NCSI: Inactive channel %u received AEN!\n",
89 if ((had_link == has_link) || chained)
93 netif_carrier_off(ndp->ndev.dev);
95 netif_carrier_on(ndp->ndev.dev);
97 if (!ndp->multi_package && !nc->package->multi_channel) {
99 ndp->flags |= NCSI_DEV_RESHUFFLE;
100 ncsi_stop_channel_monitor(nc);
101 spin_lock_irqsave(&ndp->lock, flags);
102 list_add_tail_rcu(&nc->link, &ndp->channel_queue);
103 spin_unlock_irqrestore(&ndp->lock, flags);
104 return ncsi_process_next_channel(ndp);
106 /* Configured channel came up */
111 ncm = &nc->modes[NCSI_MODE_TX_ENABLE];
112 if (ncsi_channel_is_last(ndp, nc)) {
113 /* No channels left, reconfigure */
114 return ncsi_reset_dev(&ndp->ndev);
115 } else if (ncm->enable) {
116 /* Need to failover Tx channel */
117 ncsi_update_tx_channel(ndp, nc->package, nc, NULL);
119 } else if (has_link && nc->package->preferred_channel == nc) {
120 /* Return Tx to preferred channel */
121 ncsi_update_tx_channel(ndp, nc->package, NULL, nc);
122 } else if (has_link) {
123 NCSI_FOR_EACH_PACKAGE(ndp, np) {
124 NCSI_FOR_EACH_CHANNEL(np, tmp) {
125 /* Enable Tx on this channel if the current Tx
128 ncm = &tmp->modes[NCSI_MODE_TX_ENABLE];
130 !ncsi_channel_has_link(tmp)) {
131 ncsi_update_tx_channel(ndp, nc->package,
139 /* Leave configured channels active in a multi-channel scenario so
140 * AEN events are still received.
145 static int ncsi_aen_handler_cr(struct ncsi_dev_priv *ndp,
146 struct ncsi_aen_pkt_hdr *h)
148 struct ncsi_channel *nc;
151 /* Find the NCSI channel */
152 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
156 spin_lock_irqsave(&nc->lock, flags);
157 if (!list_empty(&nc->link) ||
158 nc->state != NCSI_CHANNEL_ACTIVE) {
159 spin_unlock_irqrestore(&nc->lock, flags);
162 spin_unlock_irqrestore(&nc->lock, flags);
164 ncsi_stop_channel_monitor(nc);
165 spin_lock_irqsave(&nc->lock, flags);
166 nc->state = NCSI_CHANNEL_INVISIBLE;
167 spin_unlock_irqrestore(&nc->lock, flags);
169 spin_lock_irqsave(&ndp->lock, flags);
170 nc->state = NCSI_CHANNEL_INACTIVE;
171 list_add_tail_rcu(&nc->link, &ndp->channel_queue);
172 spin_unlock_irqrestore(&ndp->lock, flags);
173 nc->modes[NCSI_MODE_TX_ENABLE].enable = 0;
175 return ncsi_process_next_channel(ndp);
178 static int ncsi_aen_handler_hncdsc(struct ncsi_dev_priv *ndp,
179 struct ncsi_aen_pkt_hdr *h)
181 struct ncsi_channel *nc;
182 struct ncsi_channel_mode *ncm;
183 struct ncsi_aen_hncdsc_pkt *hncdsc;
186 /* Find the NCSI channel */
187 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
191 spin_lock_irqsave(&nc->lock, flags);
192 ncm = &nc->modes[NCSI_MODE_LINK];
193 hncdsc = (struct ncsi_aen_hncdsc_pkt *)h;
194 ncm->data[3] = ntohl(hncdsc->status);
195 spin_unlock_irqrestore(&nc->lock, flags);
196 netdev_dbg(ndp->ndev.dev,
197 "NCSI: host driver %srunning on channel %u\n",
198 ncm->data[3] & 0x1 ? "" : "not ", nc->id);
203 static struct ncsi_aen_handler {
206 int (*handler)(struct ncsi_dev_priv *ndp,
207 struct ncsi_aen_pkt_hdr *h);
208 } ncsi_aen_handlers[] = {
209 { NCSI_PKT_AEN_LSC, 12, ncsi_aen_handler_lsc },
210 { NCSI_PKT_AEN_CR, 4, ncsi_aen_handler_cr },
211 { NCSI_PKT_AEN_HNCDSC, 8, ncsi_aen_handler_hncdsc }
214 int ncsi_aen_handler(struct ncsi_dev_priv *ndp, struct sk_buff *skb)
216 struct ncsi_aen_pkt_hdr *h;
217 struct ncsi_aen_handler *nah = NULL;
220 /* Find the handler */
221 h = (struct ncsi_aen_pkt_hdr *)skb_network_header(skb);
222 for (i = 0; i < ARRAY_SIZE(ncsi_aen_handlers); i++) {
223 if (ncsi_aen_handlers[i].type == h->type) {
224 nah = &ncsi_aen_handlers[i];
230 netdev_warn(ndp->ndev.dev, "Invalid AEN (0x%x) received\n",
235 ret = ncsi_validate_aen_pkt(h, nah->payload);
237 netdev_warn(ndp->ndev.dev,
238 "NCSI: 'bad' packet ignored for AEN type 0x%x\n",
243 ret = nah->handler(ndp, h);
245 netdev_err(ndp->ndev.dev,
246 "NCSI: Handler for AEN type 0x%x returned %d\n",