xref: /openbmc/u-boot/drivers/net/netconsole.c (revision bf48fcb6) 
1 /*
2  * (C) Copyright 2004
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <command.h>
26 #include <stdio_dev.h>
27 #include <net.h>
28 
29 DECLARE_GLOBAL_DATA_PTR;
30 
31 #ifndef CONFIG_NETCONSOLE_BUFFER_SIZE
32 #define CONFIG_NETCONSOLE_BUFFER_SIZE 512
33 #endif
34 
35 static char input_buffer[CONFIG_NETCONSOLE_BUFFER_SIZE];
36 static int input_size; /* char count in input buffer */
37 static int input_offset; /* offset to valid chars in input buffer */
38 static int input_recursion;
39 static int output_recursion;
40 static int net_timeout;
41 static uchar nc_ether[6]; /* server enet address */
42 static IPaddr_t nc_ip; /* server ip */
43 static short nc_out_port; /* target output port */
44 static short nc_in_port; /* source input port */
45 static const char *output_packet; /* used by first send udp */
46 static int output_packet_len;
47 /*
48  * Start with a default last protocol.
49  * We are only interested in NETCONS or not.
50  */
51 enum proto_t net_loop_last_protocol = BOOTP;
52 
53 static void nc_wait_arp_handler(uchar *pkt, unsigned dest,
54 				 IPaddr_t sip, unsigned src,
55 				 unsigned len)
56 {
57 	net_set_state(NETLOOP_SUCCESS); /* got arp reply - quit net loop */
58 }
59 
60 static void nc_handler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
61 			unsigned len)
62 {
63 	if (input_size)
64 		net_set_state(NETLOOP_SUCCESS); /* got input - quit net loop */
65 }
66 
67 static void nc_timeout(void)
68 {
69 	net_set_state(NETLOOP_SUCCESS);
70 }
71 
72 static int is_broadcast(IPaddr_t ip)
73 {
74 	static IPaddr_t netmask;
75 	static IPaddr_t our_ip;
76 	static int env_changed_id;
77 	int env_id = get_env_id();
78 
79 	/* update only when the environment has changed */
80 	if (env_changed_id != env_id) {
81 		netmask = getenv_IPaddr("netmask");
82 		our_ip = getenv_IPaddr("ipaddr");
83 
84 		env_changed_id = env_id;
85 	}
86 
87 	return (ip == ~0 ||				/* 255.255.255.255 */
88 	    ((netmask & our_ip) == (netmask & ip) &&	/* on the same net */
89 	    (netmask | ip) == ~0));		/* broadcast to our net */
90 }
91 
92 static int refresh_settings_from_env(void)
93 {
94 	const char *p;
95 	static int env_changed_id;
96 	int env_id = get_env_id();
97 
98 	/* update only when the environment has changed */
99 	if (env_changed_id != env_id) {
100 		if (getenv("ncip")) {
101 			nc_ip = getenv_IPaddr("ncip");
102 			if (!nc_ip)
103 				return -1;	/* ncip is 0.0.0.0 */
104 			p = strchr(getenv("ncip"), ':');
105 			if (p != NULL) {
106 				nc_out_port = simple_strtoul(p + 1, NULL, 10);
107 				nc_in_port = nc_out_port;
108 			}
109 		} else
110 			nc_ip = ~0; /* ncip is not set, so broadcast */
111 
112 		p = getenv("ncoutport");
113 		if (p != NULL)
114 			nc_out_port = simple_strtoul(p, NULL, 10);
115 		p = getenv("ncinport");
116 		if (p != NULL)
117 			nc_in_port = simple_strtoul(p, NULL, 10);
118 
119 		if (is_broadcast(nc_ip))
120 			/* broadcast MAC address */
121 			memset(nc_ether, 0xff, sizeof(nc_ether));
122 		else
123 			/* force arp request */
124 			memset(nc_ether, 0, sizeof(nc_ether));
125 	}
126 	return 0;
127 }
128 
129 /**
130  * Called from NetLoop in net/net.c before each packet
131  */
132 void NcStart(void)
133 {
134 	refresh_settings_from_env();
135 	if (!output_packet_len || memcmp(nc_ether, NetEtherNullAddr, 6)) {
136 		/* going to check for input packet */
137 		net_set_udp_handler(nc_handler);
138 		NetSetTimeout(net_timeout, nc_timeout);
139 	} else {
140 		/* send arp request */
141 		uchar *pkt;
142 		net_set_arp_handler(nc_wait_arp_handler);
143 		pkt = (uchar *)NetTxPacket + NetEthHdrSize() + IP_UDP_HDR_SIZE;
144 		memcpy(pkt, output_packet, output_packet_len);
145 		NetSendUDPPacket(nc_ether, nc_ip, nc_out_port, nc_in_port,
146 			output_packet_len);
147 	}
148 }
149 
150 int nc_input_packet(uchar *pkt, IPaddr_t src_ip, unsigned dest_port,
151 	unsigned src_port, unsigned len)
152 {
153 	int end, chunk;
154 
155 	if (dest_port != nc_in_port || !len)
156 		return 0; /* not for us */
157 
158 	if (src_ip != nc_ip && !is_broadcast(nc_ip))
159 		return 0; /* not from our client */
160 
161 	debug_cond(DEBUG_DEV_PKT, "input: \"%*.*s\"\n", len, len, pkt);
162 
163 	if (input_size == sizeof(input_buffer))
164 		return 1; /* no space */
165 	if (len > sizeof(input_buffer) - input_size)
166 		len = sizeof(input_buffer) - input_size;
167 
168 	end = input_offset + input_size;
169 	if (end > sizeof(input_buffer))
170 		end -= sizeof(input_buffer);
171 
172 	chunk = len;
173 	if (end + len > sizeof(input_buffer)) {
174 		chunk = sizeof(input_buffer) - end;
175 		memcpy(input_buffer, pkt + chunk, len - chunk);
176 	}
177 	memcpy(input_buffer + end, pkt, chunk);
178 
179 	input_size += len;
180 
181 	return 1;
182 }
183 
184 static void nc_send_packet(const char *buf, int len)
185 {
186 	struct eth_device *eth;
187 	int inited = 0;
188 	uchar *pkt;
189 	uchar *ether;
190 	IPaddr_t ip;
191 
192 	debug_cond(DEBUG_DEV_PKT, "output: \"%*.*s\"\n", len, len, buf);
193 
194 	eth = eth_get_dev();
195 	if (eth == NULL)
196 		return;
197 
198 	if (!memcmp(nc_ether, NetEtherNullAddr, 6)) {
199 		if (eth->state == ETH_STATE_ACTIVE)
200 			return;	/* inside net loop */
201 		output_packet = buf;
202 		output_packet_len = len;
203 		NetLoop(NETCONS); /* wait for arp reply and send packet */
204 		output_packet_len = 0;
205 		return;
206 	}
207 
208 	if (eth->state != ETH_STATE_ACTIVE) {
209 		if (eth_is_on_demand_init()) {
210 			if (eth_init(gd->bd) < 0)
211 				return;
212 			eth_set_last_protocol(NETCONS);
213 		} else
214 			eth_init_state_only(gd->bd);
215 
216 		inited = 1;
217 	}
218 	pkt = (uchar *)NetTxPacket + NetEthHdrSize() + IP_UDP_HDR_SIZE;
219 	memcpy(pkt, buf, len);
220 	ether = nc_ether;
221 	ip = nc_ip;
222 	NetSendUDPPacket(ether, ip, nc_out_port, nc_in_port, len);
223 
224 	if (inited) {
225 		if (eth_is_on_demand_init())
226 			eth_halt();
227 		else
228 			eth_halt_state_only();
229 	}
230 }
231 
232 static int nc_start(void)
233 {
234 	int retval;
235 
236 	nc_out_port = 6666; /* default port */
237 	nc_in_port = nc_out_port;
238 
239 	retval = refresh_settings_from_env();
240 	if (retval != 0)
241 		return retval;
242 
243 	/*
244 	 * Initialize the static IP settings and buffer pointers
245 	 * incase we call NetSendUDPPacket before NetLoop
246 	 */
247 	net_init();
248 
249 	return 0;
250 }
251 
252 static void nc_putc(char c)
253 {
254 	if (output_recursion)
255 		return;
256 	output_recursion = 1;
257 
258 	nc_send_packet(&c, 1);
259 
260 	output_recursion = 0;
261 }
262 
263 static void nc_puts(const char *s)
264 {
265 	int len;
266 
267 	if (output_recursion)
268 		return;
269 	output_recursion = 1;
270 
271 	len = strlen(s);
272 	while (len) {
273 		int send_len = min(len, sizeof(input_buffer));
274 		nc_send_packet(s, send_len);
275 		len -= send_len;
276 		s += send_len;
277 	}
278 
279 	output_recursion = 0;
280 }
281 
282 static int nc_getc(void)
283 {
284 	uchar c;
285 
286 	input_recursion = 1;
287 
288 	net_timeout = 0;	/* no timeout */
289 	while (!input_size)
290 		NetLoop(NETCONS);
291 
292 	input_recursion = 0;
293 
294 	c = input_buffer[input_offset++];
295 
296 	if (input_offset >= sizeof(input_buffer))
297 		input_offset -= sizeof(input_buffer);
298 	input_size--;
299 
300 	return c;
301 }
302 
303 static int nc_tstc(void)
304 {
305 	struct eth_device *eth;
306 
307 	if (input_recursion)
308 		return 0;
309 
310 	if (input_size)
311 		return 1;
312 
313 	eth = eth_get_dev();
314 	if (eth && eth->state == ETH_STATE_ACTIVE)
315 		return 0;	/* inside net loop */
316 
317 	input_recursion = 1;
318 
319 	net_timeout = 1;
320 	NetLoop(NETCONS);	/* kind of poll */
321 
322 	input_recursion = 0;
323 
324 	return input_size != 0;
325 }
326 
327 int drv_nc_init(void)
328 {
329 	struct stdio_dev dev;
330 	int rc;
331 
332 	memset(&dev, 0, sizeof(dev));
333 
334 	strcpy(dev.name, "nc");
335 	dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_SYSTEM;
336 	dev.start = nc_start;
337 	dev.putc = nc_putc;
338 	dev.puts = nc_puts;
339 	dev.getc = nc_getc;
340 	dev.tstc = nc_tstc;
341 
342 	rc = stdio_register(&dev);
343 
344 	return (rc == 0) ? 1 : rc;
345 }
346