1 /*
2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
3  *              operating system.  NET  is implemented using the  BSD Socket
4  *              interface as the means of communication with the user level.
5  *
6  *              Definitions used by the ARCnet driver.
7  *
8  * Authors:     Avery Pennarun and David Woodhouse
9  *
10  *              This program is free software; you can redistribute it and/or
11  *              modify it under the terms of the GNU General Public License
12  *              as published by the Free Software Foundation; either version
13  *              2 of the License, or (at your option) any later version.
14  *
15  */
16 #ifndef _LINUX_ARCDEVICE_H
17 #define _LINUX_ARCDEVICE_H
18 
19 #include <asm/timex.h>
20 #include <linux/if_arcnet.h>
21 
22 #ifdef __KERNEL__
23 #include  <linux/irqreturn.h>
24 
25 #ifndef bool
26 #define bool int
27 #endif
28 
29 /*
30  * RECON_THRESHOLD is the maximum number of RECON messages to receive
31  * within one minute before printing a "cabling problem" warning. The
32  * default value should be fine.
33  *
34  * After that, a "cabling restored" message will be printed on the next IRQ
35  * if no RECON messages have been received for 10 seconds.
36  *
37  * Do not define RECON_THRESHOLD at all if you want to disable this feature.
38  */
39 #define RECON_THRESHOLD 30
40 
41 
42 /*
43  * Define this to the minimum "timeout" value.  If a transmit takes longer
44  * than TX_TIMEOUT jiffies, Linux will abort the TX and retry.  On a large
45  * network, or one with heavy network traffic, this timeout may need to be
46  * increased.  The larger it is, though, the longer it will be between
47  * necessary transmits - don't set this too high.
48  */
49 #define TX_TIMEOUT (HZ * 200 / 1000)
50 
51 
52 /* Display warnings about the driver being an ALPHA version. */
53 #undef ALPHA_WARNING
54 
55 
56 /*
57  * Debugging bitflags: each option can be enabled individually.
58  *
59  * Note: only debug flags included in the ARCNET_DEBUG_MAX define will
60  *   actually be available.  GCC will (at least, GCC 2.7.0 will) notice
61  *   lines using a BUGLVL not in ARCNET_DEBUG_MAX and automatically optimize
62  *   them out.
63  */
64 #define D_NORMAL	1	/* important operational info             */
65 #define D_EXTRA		2	/* useful, but non-vital information      */
66 #define	D_INIT		4	/* show init/probe messages               */
67 #define D_INIT_REASONS	8	/* show reasons for discarding probes     */
68 #define D_RECON		32	/* print a message whenever token is lost */
69 #define D_PROTO		64	/* debug auto-protocol support            */
70 /* debug levels below give LOTS of output during normal operation! */
71 #define D_DURING	128	/* trace operations (including irq's)     */
72 #define D_TX	        256	/* show tx packets                        */
73 #define D_RX		512	/* show rx packets                        */
74 #define D_SKB		1024	/* show skb's                             */
75 #define D_SKB_SIZE	2048	/* show skb sizes			  */
76 #define D_TIMING	4096	/* show time needed to copy buffers to card */
77 #define D_DEBUG         8192    /* Very detailed debug line for line */
78 
79 #ifndef ARCNET_DEBUG_MAX
80 #define ARCNET_DEBUG_MAX (127)	/* change to ~0 if you want detailed debugging */
81 #endif
82 
83 #ifndef ARCNET_DEBUG
84 #define ARCNET_DEBUG (D_NORMAL|D_EXTRA)
85 #endif
86 extern int arcnet_debug;
87 
88 /* macros to simplify debug checking */
89 #define BUGLVL(x) if ((ARCNET_DEBUG_MAX)&arcnet_debug&(x))
90 #define BUGMSG2(x,msg,args...) do { BUGLVL(x) printk(msg, ## args); } while (0)
91 #define BUGMSG(x,msg,args...) \
92 	BUGMSG2(x, "%s%6s: " msg, \
93             x==D_NORMAL	? KERN_WARNING \
94             		: x < D_DURING ? KERN_INFO : KERN_DEBUG, \
95 	    dev->name , ## args)
96 
97 /* see how long a function call takes to run, expressed in CPU cycles */
98 #define TIME(name, bytes, call) BUGLVL(D_TIMING) { \
99 	    unsigned long _x, _y; \
100 	    _x = get_cycles(); \
101 	    call; \
102 	    _y = get_cycles(); \
103 	    BUGMSG(D_TIMING, \
104 	       "%s: %d bytes in %lu cycles == " \
105 	       "%lu Kbytes/100Mcycle\n",\
106 		   name, bytes, _y - _x, \
107 		   100000000 / 1024 * bytes / (_y - _x + 1));\
108 	} \
109 	else { \
110 		    call;\
111 	}
112 
113 
114 /*
115  * Time needed to reset the card - in ms (milliseconds).  This works on my
116  * SMC PC100.  I can't find a reference that tells me just how long I
117  * should wait.
118  */
119 #define RESETtime (300)
120 
121 /*
122  * These are the max/min lengths of packet payload, not including the
123  * arc_hardware header, but definitely including the soft header.
124  *
125  * Note: packet sizes 254, 255, 256 are impossible because of the way
126  * ARCnet registers work  That's why RFC1201 defines "exception" packets.
127  * In non-RFC1201 protocols, we have to just tack some extra bytes on the
128  * end.
129  */
130 #define MTU	253		/* normal packet max size */
131 #define MinTU	257		/* extended packet min size */
132 #define XMTU	508		/* extended packet max size */
133 
134 /* status/interrupt mask bit fields */
135 #define TXFREEflag	0x01	/* transmitter available */
136 #define TXACKflag       0x02	/* transmitted msg. ackd */
137 #define RECONflag       0x04	/* network reconfigured */
138 #define TESTflag        0x08	/* test flag */
139 #define EXCNAKflag      0x08    /* excesive nak flag */
140 #define RESETflag       0x10	/* power-on-reset */
141 #define RES1flag        0x20	/* reserved - usually set by jumper */
142 #define RES2flag        0x40	/* reserved - usually set by jumper */
143 #define NORXflag        0x80	/* receiver inhibited */
144 
145 /* Flags used for IO-mapped memory operations */
146 #define AUTOINCflag     0x40	/* Increase location with each access */
147 #define IOMAPflag       0x02	/* (for 90xx) Use IO mapped memory, not mmap */
148 #define ENABLE16flag    0x80	/* (for 90xx) Enable 16-bit mode */
149 
150 /* in the command register, the following bits have these meanings:
151  *                0-2     command
152  *                3-4     page number (for enable rcv/xmt command)
153  *                 7      receive broadcasts
154  */
155 #define NOTXcmd         0x01	/* disable transmitter */
156 #define NORXcmd         0x02	/* disable receiver */
157 #define TXcmd           0x03	/* enable transmitter */
158 #define RXcmd           0x04	/* enable receiver */
159 #define CONFIGcmd       0x05	/* define configuration */
160 #define CFLAGScmd       0x06	/* clear flags */
161 #define TESTcmd         0x07	/* load test flags */
162 
163 /* flags for "clear flags" command */
164 #define RESETclear      0x08	/* power-on-reset */
165 #define CONFIGclear     0x10	/* system reconfigured */
166 
167 #define EXCNAKclear     0x0E    /* Clear and acknowledge the excive nak bit */
168 
169 /* flags for "load test flags" command */
170 #define TESTload        0x08	/* test flag (diagnostic) */
171 
172 /* byte deposited into first address of buffers on reset */
173 #define TESTvalue       0321	/* that's octal for 0xD1 :) */
174 
175 /* for "enable receiver" command */
176 #define RXbcasts        0x80	/* receive broadcasts */
177 
178 /* flags for "define configuration" command */
179 #define NORMALconf      0x00	/* 1-249 byte packets */
180 #define EXTconf         0x08	/* 250-504 byte packets */
181 
182 /* card feature flags, set during auto-detection.
183  * (currently only used by com20020pci)
184  */
185 #define ARC_IS_5MBIT    1   /* card default speed is 5MBit */
186 #define ARC_CAN_10MBIT  2   /* card uses COM20022, supporting 10MBit,
187 				 but default is 2.5MBit. */
188 
189 
190 /* information needed to define an encapsulation driver */
191 struct ArcProto {
192 	char suffix;		/* a for RFC1201, e for ether-encap, etc. */
193 	int mtu;		/* largest possible packet */
194 	int is_ip;              /* This is a ip plugin - not a raw thing */
195 
196 	void (*rx) (struct net_device * dev, int bufnum,
197 		    struct archdr * pkthdr, int length);
198 	int (*build_header) (struct sk_buff * skb, struct net_device *dev,
199 			     unsigned short ethproto, uint8_t daddr);
200 
201 	/* these functions return '1' if the skb can now be freed */
202 	int (*prepare_tx) (struct net_device * dev, struct archdr * pkt, int length,
203 			   int bufnum);
204 	int (*continue_tx) (struct net_device * dev, int bufnum);
205 	int (*ack_tx) (struct net_device * dev, int acked);
206 };
207 
208 extern struct ArcProto *arc_proto_map[256], *arc_proto_default,
209 	*arc_bcast_proto, *arc_raw_proto;
210 
211 
212 /*
213  * "Incoming" is information needed for each address that could be sending
214  * to us.  Mostly for partially-received split packets.
215  */
216 struct Incoming {
217 	struct sk_buff *skb;	/* packet data buffer             */
218 	__be16 sequence;	/* sequence number of assembly    */
219 	uint8_t lastpacket,	/* number of last packet (from 1) */
220 		numpackets;	/* number of packets in split     */
221 };
222 
223 
224 /* only needed for RFC1201 */
225 struct Outgoing {
226 	struct ArcProto *proto;	/* protocol driver that owns this:
227 				 *   if NULL, no packet is pending.
228 				 */
229 	struct sk_buff *skb;	/* buffer from upper levels */
230 	struct archdr *pkt;	/* a pointer into the skb */
231 	uint16_t length,	/* bytes total */
232 		dataleft,	/* bytes left */
233 		segnum,		/* segment being sent */
234 		numsegs;	/* number of segments */
235 };
236 
237 
238 struct arcnet_local {
239 	uint8_t config,		/* current value of CONFIG register */
240 		timeout,	/* Extended timeout for COM20020 */
241 		backplane,	/* Backplane flag for COM20020 */
242 		clockp,		/* COM20020 clock divider */
243 		clockm,		/* COM20020 clock multiplier flag */
244 		setup,		/* Contents of setup1 register */
245 		setup2,		/* Contents of setup2 register */
246 		intmask;	/* current value of INTMASK register */
247 	uint8_t default_proto[256];	/* default encap to use for each host */
248 	int	cur_tx,		/* buffer used by current transmit, or -1 */
249 		next_tx,	/* buffer where a packet is ready to send */
250 		cur_rx;		/* current receive buffer */
251 	int	lastload_dest,	/* can last loaded packet be acked? */
252 		lasttrans_dest;	/* can last TX'd packet be acked? */
253 	int	timed_out;	/* need to process TX timeout and drop packet */
254 	unsigned long last_timeout;	/* time of last reported timeout */
255 	char *card_name;	/* card ident string */
256 	int card_flags;		/* special card features */
257 
258 
259 	/* On preemtive and SMB a lock is needed */
260 	spinlock_t lock;
261 
262 	/*
263 	 * Buffer management: an ARCnet card has 4 x 512-byte buffers, each of
264 	 * which can be used for either sending or receiving.  The new dynamic
265 	 * buffer management routines use a simple circular queue of available
266 	 * buffers, and take them as they're needed.  This way, we simplify
267 	 * situations in which we (for example) want to pre-load a transmit
268 	 * buffer, or start receiving while we copy a received packet to
269 	 * memory.
270 	 *
271 	 * The rules: only the interrupt handler is allowed to _add_ buffers to
272 	 * the queue; thus, this doesn't require a lock.  Both the interrupt
273 	 * handler and the transmit function will want to _remove_ buffers, so
274 	 * we need to handle the situation where they try to do it at the same
275 	 * time.
276 	 *
277 	 * If next_buf == first_free_buf, the queue is empty.  Since there are
278 	 * only four possible buffers, the queue should never be full.
279 	 */
280 	atomic_t buf_lock;
281 	int buf_queue[5];
282 	int next_buf, first_free_buf;
283 
284 	/* network "reconfiguration" handling */
285 	unsigned long first_recon; /* time of "first" RECON message to count */
286 	unsigned long last_recon;  /* time of most recent RECON */
287 	int num_recons;		/* number of RECONs between first and last. */
288 	bool network_down;	/* do we think the network is down? */
289 
290 	bool excnak_pending;    /* We just got an excesive nak interrupt */
291 
292 	struct {
293 		uint16_t sequence;	/* sequence number (incs with each packet) */
294 		__be16 aborted_seq;
295 
296 		struct Incoming incoming[256];	/* one from each address */
297 	} rfc1201;
298 
299 	/* really only used by rfc1201, but we'll pretend it's not */
300 	struct Outgoing outgoing;	/* packet currently being sent */
301 
302 	/* hardware-specific functions */
303 	struct {
304 		struct module *owner;
305 		void (*command) (struct net_device * dev, int cmd);
306 		int (*status) (struct net_device * dev);
307 		void (*intmask) (struct net_device * dev, int mask);
308 		bool (*reset) (struct net_device * dev, bool really_reset);
309 		void (*open) (struct net_device * dev);
310 		void (*close) (struct net_device * dev);
311 
312 		void (*copy_to_card) (struct net_device * dev, int bufnum, int offset,
313 				      void *buf, int count);
314 		void (*copy_from_card) (struct net_device * dev, int bufnum, int offset,
315 					void *buf, int count);
316 	} hw;
317 
318 	void __iomem *mem_start;	/* pointer to ioremap'ed MMIO */
319 };
320 
321 
322 #define ARCRESET(x)  (lp->hw.reset(dev, (x)))
323 #define ACOMMAND(x)  (lp->hw.command(dev, (x)))
324 #define ASTATUS()    (lp->hw.status(dev))
325 #define AINTMASK(x)  (lp->hw.intmask(dev, (x)))
326 
327 
328 
329 #if ARCNET_DEBUG_MAX & D_SKB
330 void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc);
331 #else
332 #define arcnet_dump_skb(dev,skb,desc) ;
333 #endif
334 
335 void arcnet_unregister_proto(struct ArcProto *proto);
336 irqreturn_t arcnet_interrupt(int irq, void *dev_id);
337 struct net_device *alloc_arcdev(const char *name);
338 
339 int arcnet_open(struct net_device *dev);
340 int arcnet_close(struct net_device *dev);
341 netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
342 				     struct net_device *dev);
343 void arcnet_timeout(struct net_device *dev);
344 
345 #endif				/* __KERNEL__ */
346 #endif				/* _LINUX_ARCDEVICE_H */
347