xref: /openbmc/linux/drivers/atm/idt77105.c (revision 01a6e126)
1 /* drivers/atm/idt77105.c - IDT77105 (PHY) driver */
2 
3 /* Written 1999 by Greg Banks, NEC Australia <gnb@linuxfan.com>. Based on suni.c */
4 
5 
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/mm.h>
9 #include <linux/errno.h>
10 #include <linux/atmdev.h>
11 #include <linux/sonet.h>
12 #include <linux/delay.h>
13 #include <linux/timer.h>
14 #include <linux/init.h>
15 #include <linux/capability.h>
16 #include <linux/atm_idt77105.h>
17 #include <linux/spinlock.h>
18 #include <linux/slab.h>
19 #include <asm/param.h>
20 #include <linux/uaccess.h>
21 
22 #include "idt77105.h"
23 
24 #undef GENERAL_DEBUG
25 
26 #ifdef GENERAL_DEBUG
27 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
28 #else
29 #define DPRINTK(format,args...)
30 #endif
31 
32 
33 struct idt77105_priv {
34 	struct idt77105_stats stats;    /* link diagnostics */
35 	struct atm_dev *dev;		/* device back-pointer */
36 	struct idt77105_priv *next;
37         int loop_mode;
38         unsigned char old_mcr;          /* storage of MCR reg while signal lost */
39 };
40 
41 static DEFINE_SPINLOCK(idt77105_priv_lock);
42 
43 #define PRIV(dev) ((struct idt77105_priv *) dev->phy_data)
44 
45 #define PUT(val,reg) dev->ops->phy_put(dev,val,IDT77105_##reg)
46 #define GET(reg) dev->ops->phy_get(dev,IDT77105_##reg)
47 
48 static void idt77105_stats_timer_func(struct timer_list *);
49 static void idt77105_restart_timer_func(struct timer_list *);
50 
51 
52 static DEFINE_TIMER(stats_timer, idt77105_stats_timer_func);
53 static DEFINE_TIMER(restart_timer, idt77105_restart_timer_func);
54 static int start_timer = 1;
55 static struct idt77105_priv *idt77105_all = NULL;
56 
57 /*
58  * Retrieve the value of one of the IDT77105's counters.
59  * `counter' is one of the IDT77105_CTRSEL_* constants.
60  */
61 static u16 get_counter(struct atm_dev *dev, int counter)
62 {
63         u16 val;
64 
65         /* write the counter bit into PHY register 6 */
66         PUT(counter, CTRSEL);
67         /* read the low 8 bits from register 4 */
68         val = GET(CTRLO);
69         /* read the high 8 bits from register 5 */
70         val |= GET(CTRHI)<<8;
71 
72         return val;
73 }
74 
75 /*
76  * Timer function called every second to gather statistics
77  * from the 77105. This is done because the h/w registers
78  * will overflow if not read at least once per second. The
79  * kernel's stats are much higher precision. Also, having
80  * a separate copy of the stats allows implementation of
81  * an ioctl which gathers the stats *without* zero'ing them.
82  */
83 static void idt77105_stats_timer_func(struct timer_list *unused)
84 {
85 	struct idt77105_priv *walk;
86 	struct atm_dev *dev;
87 	struct idt77105_stats *stats;
88 
89         DPRINTK("IDT77105 gathering statistics\n");
90 	for (walk = idt77105_all; walk; walk = walk->next) {
91 		dev = walk->dev;
92 
93 		stats = &walk->stats;
94                 stats->symbol_errors += get_counter(dev, IDT77105_CTRSEL_SEC);
95                 stats->tx_cells += get_counter(dev, IDT77105_CTRSEL_TCC);
96                 stats->rx_cells += get_counter(dev, IDT77105_CTRSEL_RCC);
97                 stats->rx_hec_errors += get_counter(dev, IDT77105_CTRSEL_RHEC);
98 	}
99         if (!start_timer) mod_timer(&stats_timer,jiffies+IDT77105_STATS_TIMER_PERIOD);
100 }
101 
102 
103 /*
104  * A separate timer func which handles restarting PHY chips which
105  * have had the cable re-inserted after being pulled out. This is
106  * done by polling the Good Signal Bit in the Interrupt Status
107  * register every 5 seconds. The other technique (checking Good
108  * Signal Bit in the interrupt handler) cannot be used because PHY
109  * interrupts need to be disabled when the cable is pulled out
110  * to avoid lots of spurious cell error interrupts.
111  */
112 static void idt77105_restart_timer_func(struct timer_list *unused)
113 {
114 	struct idt77105_priv *walk;
115 	struct atm_dev *dev;
116         unsigned char istat;
117 
118         DPRINTK("IDT77105 checking for cable re-insertion\n");
119 	for (walk = idt77105_all; walk; walk = walk->next) {
120 		dev = walk->dev;
121 
122                 if (dev->signal != ATM_PHY_SIG_LOST)
123                     continue;
124 
125                 istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
126                 if (istat & IDT77105_ISTAT_GOODSIG) {
127                     /* Found signal again */
128                     atm_dev_signal_change(dev, ATM_PHY_SIG_FOUND);
129 	            printk(KERN_NOTICE "%s(itf %d): signal detected again\n",
130                         dev->type,dev->number);
131                     /* flush the receive FIFO */
132                     PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
133                     /* re-enable interrupts */
134 	            PUT( walk->old_mcr ,MCR);
135                 }
136 	}
137         if (!start_timer) mod_timer(&restart_timer,jiffies+IDT77105_RESTART_TIMER_PERIOD);
138 }
139 
140 
141 static int fetch_stats(struct atm_dev *dev,struct idt77105_stats __user *arg,int zero)
142 {
143 	unsigned long flags;
144 	struct idt77105_stats stats;
145 
146 	spin_lock_irqsave(&idt77105_priv_lock, flags);
147 	memcpy(&stats, &PRIV(dev)->stats, sizeof(struct idt77105_stats));
148 	if (zero)
149 		memset(&PRIV(dev)->stats, 0, sizeof(struct idt77105_stats));
150 	spin_unlock_irqrestore(&idt77105_priv_lock, flags);
151 	if (arg == NULL)
152 		return 0;
153 	return copy_to_user(arg, &stats,
154 		    sizeof(struct idt77105_stats)) ? -EFAULT : 0;
155 }
156 
157 
158 static int set_loopback(struct atm_dev *dev,int mode)
159 {
160 	int diag;
161 
162 	diag = GET(DIAG) & ~IDT77105_DIAG_LCMASK;
163 	switch (mode) {
164 		case ATM_LM_NONE:
165 			break;
166 		case ATM_LM_LOC_ATM:
167 			diag |= IDT77105_DIAG_LC_PHY_LOOPBACK;
168 			break;
169 		case ATM_LM_RMT_ATM:
170 			diag |= IDT77105_DIAG_LC_LINE_LOOPBACK;
171 			break;
172 		default:
173 			return -EINVAL;
174 	}
175 	PUT(diag,DIAG);
176 	printk(KERN_NOTICE "%s(%d) Loopback mode is: %s\n", dev->type,
177 	    dev->number,
178 	    (mode == ATM_LM_NONE ? "NONE" :
179 	      (mode == ATM_LM_LOC_ATM ? "DIAG (local)" :
180 		(mode == IDT77105_DIAG_LC_LINE_LOOPBACK ? "LOOP (remote)" :
181 		  "unknown")))
182 		    );
183 	PRIV(dev)->loop_mode = mode;
184 	return 0;
185 }
186 
187 
188 static int idt77105_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg)
189 {
190         printk(KERN_NOTICE "%s(%d) idt77105_ioctl() called\n",dev->type,dev->number);
191 	switch (cmd) {
192 		case IDT77105_GETSTATZ:
193 			if (!capable(CAP_NET_ADMIN)) return -EPERM;
194 			/* fall through */
195 		case IDT77105_GETSTAT:
196 			return fetch_stats(dev, arg, cmd == IDT77105_GETSTATZ);
197 		case ATM_SETLOOP:
198 			return set_loopback(dev,(int)(unsigned long) arg);
199 		case ATM_GETLOOP:
200 			return put_user(PRIV(dev)->loop_mode,(int __user *)arg) ?
201 			    -EFAULT : 0;
202 		case ATM_QUERYLOOP:
203 			return put_user(ATM_LM_LOC_ATM | ATM_LM_RMT_ATM,
204 			    (int __user *) arg) ? -EFAULT : 0;
205 		default:
206 			return -ENOIOCTLCMD;
207 	}
208 }
209 
210 
211 
212 static void idt77105_int(struct atm_dev *dev)
213 {
214         unsigned char istat;
215 
216         istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
217 
218         DPRINTK("IDT77105 generated an interrupt, istat=%02x\n", (unsigned)istat);
219 
220         if (istat & IDT77105_ISTAT_RSCC) {
221             /* Rx Signal Condition Change - line went up or down */
222             if (istat & IDT77105_ISTAT_GOODSIG) {   /* signal detected again */
223                 /* This should not happen (restart timer does it) but JIC */
224 		atm_dev_signal_change(dev, ATM_PHY_SIG_FOUND);
225             } else {    /* signal lost */
226                 /*
227                  * Disable interrupts and stop all transmission and
228                  * reception - the restart timer will restore these.
229                  */
230                 PRIV(dev)->old_mcr = GET(MCR);
231 	        PUT(
232                     (PRIV(dev)->old_mcr|
233                     IDT77105_MCR_DREC|
234                     IDT77105_MCR_DRIC|
235                     IDT77105_MCR_HALTTX
236                     ) & ~IDT77105_MCR_EIP, MCR);
237 		atm_dev_signal_change(dev, ATM_PHY_SIG_LOST);
238 	        printk(KERN_NOTICE "%s(itf %d): signal lost\n",
239                     dev->type,dev->number);
240             }
241         }
242 
243         if (istat & IDT77105_ISTAT_RFO) {
244             /* Rx FIFO Overrun -- perform a FIFO flush */
245             PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
246 	    printk(KERN_NOTICE "%s(itf %d): receive FIFO overrun\n",
247                 dev->type,dev->number);
248         }
249 #ifdef GENERAL_DEBUG
250         if (istat & (IDT77105_ISTAT_HECERR | IDT77105_ISTAT_SCR |
251                      IDT77105_ISTAT_RSE)) {
252             /* normally don't care - just report in stats */
253 	    printk(KERN_NOTICE "%s(itf %d): received cell with error\n",
254                 dev->type,dev->number);
255         }
256 #endif
257 }
258 
259 
260 static int idt77105_start(struct atm_dev *dev)
261 {
262 	unsigned long flags;
263 
264 	if (!(dev->dev_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
265 		return -ENOMEM;
266 	PRIV(dev)->dev = dev;
267 	spin_lock_irqsave(&idt77105_priv_lock, flags);
268 	PRIV(dev)->next = idt77105_all;
269 	idt77105_all = PRIV(dev);
270 	spin_unlock_irqrestore(&idt77105_priv_lock, flags);
271 	memset(&PRIV(dev)->stats,0,sizeof(struct idt77105_stats));
272 
273         /* initialise dev->signal from Good Signal Bit */
274 	atm_dev_signal_change(dev,
275 		GET(ISTAT) & IDT77105_ISTAT_GOODSIG ?
276 		ATM_PHY_SIG_FOUND : ATM_PHY_SIG_LOST);
277 	if (dev->signal == ATM_PHY_SIG_LOST)
278 		printk(KERN_WARNING "%s(itf %d): no signal\n",dev->type,
279 		    dev->number);
280 
281         /* initialise loop mode from hardware */
282         switch ( GET(DIAG) & IDT77105_DIAG_LCMASK ) {
283         case IDT77105_DIAG_LC_NORMAL:
284             PRIV(dev)->loop_mode = ATM_LM_NONE;
285             break;
286         case IDT77105_DIAG_LC_PHY_LOOPBACK:
287             PRIV(dev)->loop_mode = ATM_LM_LOC_ATM;
288             break;
289         case IDT77105_DIAG_LC_LINE_LOOPBACK:
290             PRIV(dev)->loop_mode = ATM_LM_RMT_ATM;
291             break;
292         }
293 
294         /* enable interrupts, e.g. on loss of signal */
295         PRIV(dev)->old_mcr = GET(MCR);
296         if (dev->signal == ATM_PHY_SIG_FOUND) {
297             PRIV(dev)->old_mcr |= IDT77105_MCR_EIP;
298 	    PUT(PRIV(dev)->old_mcr, MCR);
299         }
300 
301 
302 	idt77105_stats_timer_func(0); /* clear 77105 counters */
303 	(void) fetch_stats(dev,NULL,1); /* clear kernel counters */
304 
305 	spin_lock_irqsave(&idt77105_priv_lock, flags);
306 	if (start_timer) {
307 		start_timer = 0;
308 
309 		stats_timer.expires = jiffies+IDT77105_STATS_TIMER_PERIOD;
310 		add_timer(&stats_timer);
311 
312 		restart_timer.expires = jiffies+IDT77105_RESTART_TIMER_PERIOD;
313 		add_timer(&restart_timer);
314 	}
315 	spin_unlock_irqrestore(&idt77105_priv_lock, flags);
316 	return 0;
317 }
318 
319 
320 static int idt77105_stop(struct atm_dev *dev)
321 {
322 	struct idt77105_priv *walk, *prev;
323 
324         DPRINTK("%s(itf %d): stopping IDT77105\n",dev->type,dev->number);
325 
326         /* disable interrupts */
327 	PUT( GET(MCR) & ~IDT77105_MCR_EIP, MCR );
328 
329         /* detach private struct from atm_dev & free */
330 	for (prev = NULL, walk = idt77105_all ;
331              walk != NULL;
332              prev = walk, walk = walk->next) {
333             if (walk->dev == dev) {
334                 if (prev != NULL)
335                     prev->next = walk->next;
336                 else
337                     idt77105_all = walk->next;
338 	        dev->phy = NULL;
339                 dev->dev_data = NULL;
340                 kfree(walk);
341                 break;
342             }
343         }
344 
345 	return 0;
346 }
347 
348 
349 static const struct atmphy_ops idt77105_ops = {
350 	.start = 	idt77105_start,
351 	.ioctl =	idt77105_ioctl,
352 	.interrupt =	idt77105_int,
353 	.stop =		idt77105_stop,
354 };
355 
356 
357 int idt77105_init(struct atm_dev *dev)
358 {
359 	dev->phy = &idt77105_ops;
360 	return 0;
361 }
362 
363 EXPORT_SYMBOL(idt77105_init);
364 
365 static void __exit idt77105_exit(void)
366 {
367 	/* turn off timers */
368 	del_timer_sync(&stats_timer);
369 	del_timer_sync(&restart_timer);
370 }
371 
372 module_exit(idt77105_exit);
373 
374 MODULE_LICENSE("GPL");
375