xref: /openbmc/linux/arch/m68k/emu/nfeth.c (revision f7777dcc)
1 /*
2  * atari_nfeth.c - ARAnyM ethernet card driver for GNU/Linux
3  *
4  * Copyright (c) 2005 Milan Jurik, Petr Stehlik of ARAnyM dev team
5  *
6  * Based on ARAnyM driver for FreeMiNT written by Standa Opichal
7  *
8  * This software may be used and distributed according to the terms of
9  * the GNU General Public License (GPL), incorporated herein by reference.
10  */
11 
12 #define DRV_VERSION	"0.3"
13 #define DRV_RELDATE	"10/12/2005"
14 
15 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
16 
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <asm/natfeat.h>
22 #include <asm/virtconvert.h>
23 
24 enum {
25 	GET_VERSION = 0,/* no parameters, return NFAPI_VERSION in d0 */
26 	XIF_INTLEVEL,	/* no parameters, return Interrupt Level in d0 */
27 	XIF_IRQ,	/* acknowledge interrupt from host */
28 	XIF_START,	/* (ethX), called on 'ifup', start receiver thread */
29 	XIF_STOP,	/* (ethX), called on 'ifdown', stop the thread */
30 	XIF_READLENGTH,	/* (ethX), return size of network data block to read */
31 	XIF_READBLOCK,	/* (ethX, buffer, size), read block of network data */
32 	XIF_WRITEBLOCK,	/* (ethX, buffer, size), write block of network data */
33 	XIF_GET_MAC,	/* (ethX, buffer, size), return MAC HW addr in buffer */
34 	XIF_GET_IPHOST,	/* (ethX, buffer, size), return IP address of host */
35 	XIF_GET_IPATARI,/* (ethX, buffer, size), return IP address of atari */
36 	XIF_GET_NETMASK	/* (ethX, buffer, size), return IP netmask */
37 };
38 
39 #define MAX_UNIT	8
40 
41 /* These identify the driver base version and may not be removed. */
42 static const char version[] =
43 	KERN_INFO KBUILD_MODNAME ".c:v" DRV_VERSION " " DRV_RELDATE
44 	" S.Opichal, M.Jurik, P.Stehlik\n"
45 	KERN_INFO " http://aranym.org/\n";
46 
47 MODULE_AUTHOR("Milan Jurik");
48 MODULE_DESCRIPTION("Atari NFeth driver");
49 MODULE_LICENSE("GPL");
50 /*
51 MODULE_PARM(nfeth_debug, "i");
52 MODULE_PARM_DESC(nfeth_debug, "nfeth_debug level (1-2)");
53 */
54 
55 
56 static long nfEtherID;
57 static int nfEtherIRQ;
58 
59 struct nfeth_private {
60 	int ethX;
61 };
62 
63 static struct net_device *nfeth_dev[MAX_UNIT];
64 
65 static int nfeth_open(struct net_device *dev)
66 {
67 	struct nfeth_private *priv = netdev_priv(dev);
68 	int res;
69 
70 	res = nf_call(nfEtherID + XIF_START, priv->ethX);
71 	netdev_dbg(dev, "%s: %d\n", __func__, res);
72 
73 	/* Ready for data */
74 	netif_start_queue(dev);
75 
76 	return 0;
77 }
78 
79 static int nfeth_stop(struct net_device *dev)
80 {
81 	struct nfeth_private *priv = netdev_priv(dev);
82 
83 	/* No more data */
84 	netif_stop_queue(dev);
85 
86 	nf_call(nfEtherID + XIF_STOP, priv->ethX);
87 
88 	return 0;
89 }
90 
91 /*
92  * Read a packet out of the adapter and pass it to the upper layers
93  */
94 static inline void recv_packet(struct net_device *dev)
95 {
96 	struct nfeth_private *priv = netdev_priv(dev);
97 	unsigned short pktlen;
98 	struct sk_buff *skb;
99 
100 	/* read packet length (excluding 32 bit crc) */
101 	pktlen = nf_call(nfEtherID + XIF_READLENGTH, priv->ethX);
102 
103 	netdev_dbg(dev, "%s: %u\n", __func__, pktlen);
104 
105 	if (!pktlen) {
106 		netdev_dbg(dev, "%s: pktlen == 0\n", __func__);
107 		dev->stats.rx_errors++;
108 		return;
109 	}
110 
111 	skb = dev_alloc_skb(pktlen + 2);
112 	if (!skb) {
113 		netdev_dbg(dev, "%s: out of mem (buf_alloc failed)\n",
114 			   __func__);
115 		dev->stats.rx_dropped++;
116 		return;
117 	}
118 
119 	skb->dev = dev;
120 	skb_reserve(skb, 2);		/* 16 Byte align  */
121 	skb_put(skb, pktlen);		/* make room */
122 	nf_call(nfEtherID + XIF_READBLOCK, priv->ethX, virt_to_phys(skb->data),
123 		pktlen);
124 
125 	skb->protocol = eth_type_trans(skb, dev);
126 	netif_rx(skb);
127 	dev->last_rx = jiffies;
128 	dev->stats.rx_packets++;
129 	dev->stats.rx_bytes += pktlen;
130 
131 	/* and enqueue packet */
132 	return;
133 }
134 
135 static irqreturn_t nfeth_interrupt(int irq, void *dev_id)
136 {
137 	int i, m, mask;
138 
139 	mask = nf_call(nfEtherID + XIF_IRQ, 0);
140 	for (i = 0, m = 1; i < MAX_UNIT; m <<= 1, i++) {
141 		if (mask & m && nfeth_dev[i]) {
142 			recv_packet(nfeth_dev[i]);
143 			nf_call(nfEtherID + XIF_IRQ, m);
144 		}
145 	}
146 	return IRQ_HANDLED;
147 }
148 
149 static int nfeth_xmit(struct sk_buff *skb, struct net_device *dev)
150 {
151 	unsigned int len;
152 	char *data, shortpkt[ETH_ZLEN];
153 	struct nfeth_private *priv = netdev_priv(dev);
154 
155 	data = skb->data;
156 	len = skb->len;
157 	if (len < ETH_ZLEN) {
158 		memset(shortpkt, 0, ETH_ZLEN);
159 		memcpy(shortpkt, data, len);
160 		data = shortpkt;
161 		len = ETH_ZLEN;
162 	}
163 
164 	netdev_dbg(dev, "%s: send %u bytes\n", __func__, len);
165 	nf_call(nfEtherID + XIF_WRITEBLOCK, priv->ethX, virt_to_phys(data),
166 		len);
167 
168 	dev->stats.tx_packets++;
169 	dev->stats.tx_bytes += len;
170 
171 	dev_kfree_skb(skb);
172 	return 0;
173 }
174 
175 static void nfeth_tx_timeout(struct net_device *dev)
176 {
177 	dev->stats.tx_errors++;
178 	netif_wake_queue(dev);
179 }
180 
181 static const struct net_device_ops nfeth_netdev_ops = {
182 	.ndo_open		= nfeth_open,
183 	.ndo_stop		= nfeth_stop,
184 	.ndo_start_xmit		= nfeth_xmit,
185 	.ndo_tx_timeout		= nfeth_tx_timeout,
186 	.ndo_validate_addr	= eth_validate_addr,
187 	.ndo_change_mtu		= eth_change_mtu,
188 	.ndo_set_mac_address	= eth_mac_addr,
189 };
190 
191 static struct net_device * __init nfeth_probe(int unit)
192 {
193 	struct net_device *dev;
194 	struct nfeth_private *priv;
195 	char mac[ETH_ALEN], host_ip[32], local_ip[32];
196 	int err;
197 
198 	if (!nf_call(nfEtherID + XIF_GET_MAC, unit, virt_to_phys(mac),
199 		     ETH_ALEN))
200 		return NULL;
201 
202 	dev = alloc_etherdev(sizeof(struct nfeth_private));
203 	if (!dev)
204 		return NULL;
205 
206 	dev->irq = nfEtherIRQ;
207 	dev->netdev_ops = &nfeth_netdev_ops;
208 
209 	memcpy(dev->dev_addr, mac, ETH_ALEN);
210 
211 	priv = netdev_priv(dev);
212 	priv->ethX = unit;
213 
214 	err = register_netdev(dev);
215 	if (err) {
216 		free_netdev(dev);
217 		return NULL;
218 	}
219 
220 	nf_call(nfEtherID + XIF_GET_IPHOST, unit,
221 		virt_to_phys(host_ip), sizeof(host_ip));
222 	nf_call(nfEtherID + XIF_GET_IPATARI, unit,
223 		virt_to_phys(local_ip), sizeof(local_ip));
224 
225 	netdev_info(dev, KBUILD_MODNAME " addr:%s (%s) HWaddr:%pM\n", host_ip,
226 		    local_ip, mac);
227 
228 	return dev;
229 }
230 
231 static int __init nfeth_init(void)
232 {
233 	long ver;
234 	int error, i;
235 
236 	nfEtherID = nf_get_id("ETHERNET");
237 	if (!nfEtherID)
238 		return -ENODEV;
239 
240 	ver = nf_call(nfEtherID + GET_VERSION);
241 	pr_info("API %lu\n", ver);
242 
243 	nfEtherIRQ = nf_call(nfEtherID + XIF_INTLEVEL);
244 	error = request_irq(nfEtherIRQ, nfeth_interrupt, IRQF_SHARED,
245 			    "eth emu", nfeth_interrupt);
246 	if (error) {
247 		pr_err("request for irq %d failed %d", nfEtherIRQ, error);
248 		return error;
249 	}
250 
251 	for (i = 0; i < MAX_UNIT; i++)
252 		nfeth_dev[i] = nfeth_probe(i);
253 
254 	return 0;
255 }
256 
257 static void __exit nfeth_cleanup(void)
258 {
259 	int i;
260 
261 	for (i = 0; i < MAX_UNIT; i++) {
262 		if (nfeth_dev[i]) {
263 			unregister_netdev(nfeth_dev[0]);
264 			free_netdev(nfeth_dev[0]);
265 		}
266 	}
267 	free_irq(nfEtherIRQ, nfeth_interrupt);
268 }
269 
270 module_init(nfeth_init);
271 module_exit(nfeth_cleanup);
272