drivers/atm/idt77105.c

   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/sched.h>
   8 #include <linux/kernel.h>
   9 #include <linux/mm.h>
  10 #include <linux/errno.h>
  11 #include <linux/atmdev.h>
  12 #include <linux/sonet.h>
  13 #include <linux/delay.h>
  14 #include <linux/timer.h>
  15 #include <linux/init.h>
  16 #include <linux/capability.h>
  17 #include <linux/atm_idt77105.h>
  18 #include <linux/spinlock.h>
  19 #include <asm/system.h>
  20 #include <asm/param.h>
  21 #include <asm/uaccess.h>
  22
  23 #include "idt77105.h"
  24
  25 #undef GENERAL_DEBUG
  26
  27 #ifdef GENERAL_DEBUG
  28 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  29 #else
  30 #define DPRINTK(format,args...)
  31 #endif
  32
  33
  34 struct idt77105_priv {
  35         struct idt77105_stats stats;    /* link diagnostics */
  36         struct atm_dev *dev;            /* device back-pointer */
  37         struct idt77105_priv *next;
  38         int loop_mode;
  39         unsigned char old_mcr;          /* storage of MCR reg while signal lost */
  40 };
  41
  42 static spinlock_t idt77105_priv_lock = SPIN_LOCK_UNLOCKED;
  43
  44 #define PRIV(dev) ((struct idt77105_priv *) dev->phy_data)
  45
  46 #define PUT(val,reg) dev->ops->phy_put(dev,val,IDT77105_##reg)
  47 #define GET(reg) dev->ops->phy_get(dev,IDT77105_##reg)
  48
  49 static void idt77105_stats_timer_func(unsigned long);
  50 static void idt77105_restart_timer_func(unsigned long);
  51
  52
  53 static struct timer_list stats_timer =
  54     TIMER_INITIALIZER(idt77105_stats_timer_func, 0, 0);
  55 static struct timer_list restart_timer =
  56     TIMER_INITIALIZER(idt77105_restart_timer_func, 0, 0);
  57 static int start_timer = 1;
  58 static struct idt77105_priv *idt77105_all = NULL;
  59
  60 /*
  61  * Retrieve the value of one of the IDT77105's counters.
  62  * `counter' is one of the IDT77105_CTRSEL_* constants.
  63  */
  64 static u16 get_counter(struct atm_dev *dev, int counter)
  65 {
  66         u16 val;
  67
  68         /* write the counter bit into PHY register 6 */
  69         PUT(counter, CTRSEL);
  70         /* read the low 8 bits from register 4 */
  71         val = GET(CTRLO);
  72         /* read the high 8 bits from register 5 */
  73         val |= GET(CTRHI)<<8;
  74
  75         return val;
  76 }
  77
  78 /*
  79  * Timer function called every second to gather statistics
  80  * from the 77105. This is done because the h/w registers
  81  * will overflow if not read at least once per second. The
  82  * kernel's stats are much higher precision. Also, having
  83  * a separate copy of the stats allows implementation of
  84  * an ioctl which gathers the stats *without* zero'ing them.
  85  */
  86 static void idt77105_stats_timer_func(unsigned long dummy)
  87 {
  88         struct idt77105_priv *walk;
  89         struct atm_dev *dev;
  90         struct idt77105_stats *stats;
  91
  92         DPRINTK("IDT77105 gathering statistics\n");
  93         for (walk = idt77105_all; walk; walk = walk->next) {
  94                 dev = walk->dev;
  95
  96                 stats = &walk->stats;
  97                 stats->symbol_errors += get_counter(dev, IDT77105_CTRSEL_SEC);
  98                 stats->tx_cells += get_counter(dev, IDT77105_CTRSEL_TCC);
  99                 stats->rx_cells += get_counter(dev, IDT77105_CTRSEL_RCC);
 100                 stats->rx_hec_errors += get_counter(dev, IDT77105_CTRSEL_RHEC);
 101         }
 102         if (!start_timer) mod_timer(&stats_timer,jiffies+IDT77105_STATS_TIMER_PERIOD);
 103 }
 104
 105
 106 /*
 107  * A separate timer func which handles restarting PHY chips which
 108  * have had the cable re-inserted after being pulled out. This is
 109  * done by polling the Good Signal Bit in the Interrupt Status
 110  * register every 5 seconds. The other technique (checking Good
 111  * Signal Bit in the interrupt handler) cannot be used because PHY
 112  * interrupts need to be disabled when the cable is pulled out
 113  * to avoid lots of spurious cell error interrupts.
 114  */
 115 static void idt77105_restart_timer_func(unsigned long dummy)
 116 {
 117         struct idt77105_priv *walk;
 118         struct atm_dev *dev;
 119         unsigned char istat;
 120
 121         DPRINTK("IDT77105 checking for cable re-insertion\n");
 122         for (walk = idt77105_all; walk; walk = walk->next) {
 123                 dev = walk->dev;
 124
 125                 if (dev->signal != ATM_PHY_SIG_LOST)
 126                     continue;
 127
 128                 istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
 129                 if (istat & IDT77105_ISTAT_GOODSIG) {
 130                     /* Found signal again */
 131                     dev->signal = ATM_PHY_SIG_FOUND;
 132                     printk(KERN_NOTICE "%s(itf %d): signal detected again\n",
 133                         dev->type,dev->number);
 134                     /* flush the receive FIFO */
 135                     PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
 136                     /* re-enable interrupts */
 137                     PUT( walk->old_mcr ,MCR);
 138                 }
 139         }
 140         if (!start_timer) mod_timer(&restart_timer,jiffies+IDT77105_RESTART_TIMER_PERIOD);
 141 }
 142
 143
 144 static int fetch_stats(struct atm_dev *dev,struct idt77105_stats __user *arg,int zero)
 145 {
 146         unsigned long flags;
 147         struct idt77105_stats stats;
 148
 149         spin_lock_irqsave(&idt77105_priv_lock, flags);
 150         memcpy(&stats, &PRIV(dev)->stats, sizeof(struct idt77105_stats));
 151         if (zero)
 152                 memset(&PRIV(dev)->stats, 0, sizeof(struct idt77105_stats));
 153         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 154         if (arg == NULL)
 155                 return 0;
 156         return copy_to_user(arg, &PRIV(dev)->stats,
 157                     sizeof(struct idt77105_stats)) ? -EFAULT : 0;
 158 }
 159
 160
 161 static int set_loopback(struct atm_dev *dev,int mode)
 162 {
 163         int diag;
 164
 165         diag = GET(DIAG) & ~IDT77105_DIAG_LCMASK;
 166         switch (mode) {
 167                 case ATM_LM_NONE:
 168                         break;
 169                 case ATM_LM_LOC_ATM:
 170                         diag |= IDT77105_DIAG_LC_PHY_LOOPBACK;
 171                         break;
 172                 case ATM_LM_RMT_ATM:
 173                         diag |= IDT77105_DIAG_LC_LINE_LOOPBACK;
 174                         break;
 175                 default:
 176                         return -EINVAL;
 177         }
 178         PUT(diag,DIAG);
 179         printk(KERN_NOTICE "%s(%d) Loopback mode is: %s\n", dev->type,
 180             dev->number,
 181             (mode == ATM_LM_NONE ? "NONE" :
 182               (mode == ATM_LM_LOC_ATM ? "DIAG (local)" :
 183                 (mode == IDT77105_DIAG_LC_LINE_LOOPBACK ? "LOOP (remote)" :
 184                   "unknown")))
 185                     );
 186         PRIV(dev)->loop_mode = mode;
 187         return 0;
 188 }
 189
 190
 191 static int idt77105_ioctl(struct atm_dev *dev,unsigned int cmd,void __user *arg)
 192 {
 193         printk(KERN_NOTICE "%s(%d) idt77105_ioctl() called\n",dev->type,dev->number);
 194         switch (cmd) {
 195                 case IDT77105_GETSTATZ:
 196                         if (!capable(CAP_NET_ADMIN)) return -EPERM;
 197                         /* fall through */
 198                 case IDT77105_GETSTAT:
 199                         return fetch_stats(dev, arg, cmd == IDT77105_GETSTATZ);
 200                 case ATM_SETLOOP:
 201                         return set_loopback(dev,(int)(unsigned long) arg);
 202                 case ATM_GETLOOP:
 203                         return put_user(PRIV(dev)->loop_mode,(int __user *)arg) ?
 204                             -EFAULT : 0;
 205                 case ATM_QUERYLOOP:
 206                         return put_user(ATM_LM_LOC_ATM | ATM_LM_RMT_ATM,
 207                             (int __user *) arg) ? -EFAULT : 0;
 208                 default:
 209                         return -ENOIOCTLCMD;
 210         }
 211 }
 212
 213
 214
 215 static void idt77105_int(struct atm_dev *dev)
 216 {
 217         unsigned char istat;
 218
 219         istat = GET(ISTAT); /* side effect: clears all interrupt status bits */
 220
 221         DPRINTK("IDT77105 generated an interrupt, istat=%02x\n", (unsigned)istat);
 222
 223         if (istat & IDT77105_ISTAT_RSCC) {
 224             /* Rx Signal Condition Change - line went up or down */
 225             if (istat & IDT77105_ISTAT_GOODSIG) {   /* signal detected again */
 226                 /* This should not happen (restart timer does it) but JIC */
 227                 dev->signal = ATM_PHY_SIG_FOUND;
 228             } else {    /* signal lost */
 229                 /*
 230                  * Disable interrupts and stop all transmission and
 231                  * reception - the restart timer will restore these.
 232                  */
 233                 PRIV(dev)->old_mcr = GET(MCR);
 234                 PUT(
 235                     (PRIV(dev)->old_mcr|
 236                     IDT77105_MCR_DREC|
 237                     IDT77105_MCR_DRIC|
 238                     IDT77105_MCR_HALTTX
 239                     ) & ~IDT77105_MCR_EIP, MCR);
 240                 dev->signal = ATM_PHY_SIG_LOST;
 241                 printk(KERN_NOTICE "%s(itf %d): signal lost\n",
 242                     dev->type,dev->number);
 243             }
 244         }
 245
 246         if (istat & IDT77105_ISTAT_RFO) {
 247             /* Rx FIFO Overrun -- perform a FIFO flush */
 248             PUT( GET(DIAG) | IDT77105_DIAG_RFLUSH, DIAG);
 249             printk(KERN_NOTICE "%s(itf %d): receive FIFO overrun\n",
 250                 dev->type,dev->number);
 251         }
 252 #ifdef GENERAL_DEBUG
 253         if (istat & (IDT77105_ISTAT_HECERR | IDT77105_ISTAT_SCR |
 254                      IDT77105_ISTAT_RSE)) {
 255             /* normally don't care - just report in stats */
 256             printk(KERN_NOTICE "%s(itf %d): received cell with error\n",
 257                 dev->type,dev->number);
 258         }
 259 #endif
 260 }
 261
 262
 263 static int idt77105_start(struct atm_dev *dev)
 264 {
 265         unsigned long flags;
 266
 267         if (!(dev->dev_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
 268                 return -ENOMEM;
 269         PRIV(dev)->dev = dev;
 270         spin_lock_irqsave(&idt77105_priv_lock, flags);
 271         PRIV(dev)->next = idt77105_all;
 272         idt77105_all = PRIV(dev);
 273         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 274         memset(&PRIV(dev)->stats,0,sizeof(struct idt77105_stats));
 275
 276         /* initialise dev->signal from Good Signal Bit */
 277         dev->signal = GET(ISTAT) & IDT77105_ISTAT_GOODSIG ? ATM_PHY_SIG_FOUND :
 278           ATM_PHY_SIG_LOST;
 279         if (dev->signal == ATM_PHY_SIG_LOST)
 280                 printk(KERN_WARNING "%s(itf %d): no signal\n",dev->type,
 281                     dev->number);
 282
 283         /* initialise loop mode from hardware */
 284         switch ( GET(DIAG) & IDT77105_DIAG_LCMASK ) {
 285         case IDT77105_DIAG_LC_NORMAL:
 286             PRIV(dev)->loop_mode = ATM_LM_NONE;
 287             break;
 288         case IDT77105_DIAG_LC_PHY_LOOPBACK:
 289             PRIV(dev)->loop_mode = ATM_LM_LOC_ATM;
 290             break;
 291         case IDT77105_DIAG_LC_LINE_LOOPBACK:
 292             PRIV(dev)->loop_mode = ATM_LM_RMT_ATM;
 293             break;
 294         }
 295
 296         /* enable interrupts, e.g. on loss of signal */
 297         PRIV(dev)->old_mcr = GET(MCR);
 298         if (dev->signal == ATM_PHY_SIG_FOUND) {
 299             PRIV(dev)->old_mcr |= IDT77105_MCR_EIP;
 300             PUT(PRIV(dev)->old_mcr, MCR);
 301         }
 302
 303
 304         idt77105_stats_timer_func(0); /* clear 77105 counters */
 305         (void) fetch_stats(dev,NULL,1); /* clear kernel counters */
 306
 307         spin_lock_irqsave(&idt77105_priv_lock, flags);
 308         if (start_timer) {
 309                 start_timer = 0;
 310
 311                 init_timer(&stats_timer);
 312                 stats_timer.expires = jiffies+IDT77105_STATS_TIMER_PERIOD;
 313                 stats_timer.function = idt77105_stats_timer_func;
 314                 add_timer(&stats_timer);
 315
 316                 init_timer(&restart_timer);
 317                 restart_timer.expires = jiffies+IDT77105_RESTART_TIMER_PERIOD;
 318                 restart_timer.function = idt77105_restart_timer_func;
 319                 add_timer(&restart_timer);
 320         }
 321         spin_unlock_irqrestore(&idt77105_priv_lock, flags);
 322         return 0;
 323 }
 324
 325
 326 int idt77105_stop(struct atm_dev *dev)
 327 {
 328         struct idt77105_priv *walk, *prev;
 329
 330         DPRINTK("%s(itf %d): stopping IDT77105\n",dev->type,dev->number);
 331
 332         /* disable interrupts */
 333         PUT( GET(MCR) & ~IDT77105_MCR_EIP, MCR );
 334
 335         /* detach private struct from atm_dev & free */
 336         for (prev = NULL, walk = idt77105_all ;
 337              walk != NULL;
 338              prev = walk, walk = walk->next) {
 339             if (walk->dev == dev) {
 340                 if (prev != NULL)
 341                     prev->next = walk->next;
 342                 else
 343                     idt77105_all = walk->next;
 344                 dev->phy = NULL;
 345                 dev->dev_data = NULL;
 346                 kfree(walk);
 347                 break;
 348             }
 349         }
 350
 351         return 0;
 352 }
 353
 354
 355 static const struct atmphy_ops idt77105_ops = {
 356         .start =        idt77105_start,
 357         .ioctl =        idt77105_ioctl,
 358         .interrupt =    idt77105_int,
 359         .stop =         idt77105_stop,
 360 };
 361
 362
 363 int idt77105_init(struct atm_dev *dev)
 364 {
 365         dev->phy = &idt77105_ops;
 366         return 0;
 367 }
 368
 369 EXPORT_SYMBOL(idt77105_init);
 370
 371 static void __exit idt77105_exit(void)
 372 {
 373         /* turn off timers */
 374         del_timer(&stats_timer);
 375         del_timer(&restart_timer);
 376 }
 377
 378 module_exit(idt77105_exit);
 379
 380 MODULE_LICENSE("GPL");