arch/m68k/q40/q40ints.c

   1 /*
   2  * arch/m68k/q40/q40ints.c
   3  *
   4  * Copyright (C) 1999,2001 Richard Zidlicky
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file COPYING in the main directory of this archive
   8  * for more details.
   9  *
  10  * .. used to be loosely based on bvme6000ints.c
  11  *
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/string.h>
  18 #include <linux/sched.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/hardirq.h>
  22
  23 #include <asm/rtc.h>
  24 #include <asm/ptrace.h>
  25 #include <asm/system.h>
  26 #include <asm/irq.h>
  27 #include <asm/traps.h>
  28
  29 #include <asm/q40_master.h>
  30 #include <asm/q40ints.h>
  31
  32 /*
  33  * Q40 IRQs are defined as follows:
  34  *            3,4,5,6,7,10,11,14,15 : ISA dev IRQs
  35  *            16-31: reserved
  36  *            32   : keyboard int
  37  *            33   : frame int (50/200 Hz periodic timer)
  38  *            34   : sample int (10/20 KHz periodic timer)
  39  *
  40 */
  41
  42 extern int ints_inited;
  43
  44
  45 irqreturn_t q40_irq2_handler (int, void *, struct pt_regs *fp);
  46
  47
  48 static irqreturn_t q40_defhand (int irq, void *dev_id, struct pt_regs *fp);
  49 static irqreturn_t default_handler(int lev, void *dev_id, struct pt_regs *regs);
  50
  51
  52 #define DEVNAME_SIZE 24
  53
  54 static struct q40_irq_node {
  55         irqreturn_t     (*handler)(int, void *, struct pt_regs *);
  56         unsigned long   flags;
  57         void            *dev_id;
  58   /*        struct q40_irq_node *next;*/
  59         char            devname[DEVNAME_SIZE];
  60         unsigned        count;
  61         unsigned short  state;
  62 } irq_tab[Q40_IRQ_MAX+1];
  63
  64 short unsigned q40_ablecount[Q40_IRQ_MAX+1];
  65
  66 /*
  67  * void q40_init_IRQ (void)
  68  *
  69  * Parameters:  None
  70  *
  71  * Returns:     Nothing
  72  *
  73  * This function is called during kernel startup to initialize
  74  * the q40 IRQ handling routines.
  75  */
  76
  77 static int disabled=0;
  78
  79 void q40_init_IRQ (void)
  80 {
  81         int i;
  82
  83         disabled=0;
  84         for (i = 0; i <= Q40_IRQ_MAX; i++) {
  85                 irq_tab[i].handler = q40_defhand;
  86                 irq_tab[i].flags = 0;
  87                 irq_tab[i].dev_id = NULL;
  88                 /*              irq_tab[i].next = NULL;*/
  89                 irq_tab[i].devname[0] = 0;
  90                 irq_tab[i].count = 0;
  91                 irq_tab[i].state =0;
  92                 q40_ablecount[i]=0;   /* all enabled */
  93         }
  94
  95         /* setup handler for ISA ints */
  96         cpu_request_irq(IRQ2, q40_irq2_handler, 0, "q40 ISA and master chip",
  97                         NULL);
  98
  99         /* now enable some ints.. */
 100         master_outb(1,EXT_ENABLE_REG);  /* ISA IRQ 5-15 */
 101
 102         /* make sure keyboard IRQ is disabled */
 103         master_outb(0,KEY_IRQ_ENABLE_REG);
 104 }
 105
 106 int q40_request_irq(unsigned int irq,
 107                 irqreturn_t (*handler)(int, void *, struct pt_regs *),
 108                 unsigned long flags, const char *devname, void *dev_id)
 109 {
 110   /*printk("q40_request_irq %d, %s\n",irq,devname);*/
 111
 112         if (irq > Q40_IRQ_MAX || (irq>15 && irq<32)) {
 113                 printk("%s: Incorrect IRQ %d from %s\n", __FUNCTION__, irq, devname);
 114                 return -ENXIO;
 115         }
 116
 117         /* test for ISA ints not implemented by HW */
 118         switch (irq)
 119           {
 120           case 1: case 2: case 8: case 9:
 121           case 12: case 13:
 122             printk("%s: ISA IRQ %d from %s not implemented by HW\n", __FUNCTION__, irq, devname);
 123             return -ENXIO;
 124           case 11:
 125             printk("warning IRQ 10 and 11 not distinguishable\n");
 126             irq=10;
 127           default:
 128             ;
 129           }
 130
 131         if (irq<Q40_IRQ_SAMPLE)
 132           {
 133             if (irq_tab[irq].dev_id != NULL)
 134                   {
 135                     printk("%s: IRQ %d from %s is not replaceable\n",
 136                            __FUNCTION__, irq, irq_tab[irq].devname);
 137                     return -EBUSY;
 138                   }
 139             /*printk("IRQ %d set to handler %p\n",irq,handler);*/
 140             if (dev_id==NULL)
 141                   {
 142                 printk("WARNING: dev_id == NULL in request_irq\n");
 143                 dev_id=(void*)1;
 144               }
 145             irq_tab[irq].handler = handler;
 146             irq_tab[irq].flags   = flags;
 147             irq_tab[irq].dev_id  = dev_id;
 148             strlcpy(irq_tab[irq].devname,devname,sizeof(irq_tab[irq].devname));
 149             irq_tab[irq].state = 0;
 150             return 0;
 151           }
 152         else {
 153           /* Q40_IRQ_SAMPLE :somewhat special actions required here ..*/
 154           cpu_request_irq(4, handler, flags, devname, dev_id);
 155           cpu_request_irq(6, handler, flags, devname, dev_id);
 156           return 0;
 157         }
 158 }
 159
 160 void q40_free_irq(unsigned int irq, void *dev_id)
 161 {
 162         if (irq > Q40_IRQ_MAX || (irq>15 && irq<32)) {
 163                 printk("%s: Incorrect IRQ %d, dev_id %x \n", __FUNCTION__, irq, (unsigned)dev_id);
 164                 return;
 165         }
 166
 167         /* test for ISA ints not implemented by HW */
 168         switch (irq)
 169           {
 170           case 1: case 2: case 8: case 9:
 171           case 12: case 13:
 172             printk("%s: ISA IRQ %d from %x invalid\n", __FUNCTION__, irq, (unsigned)dev_id);
 173             return;
 174           case 11: irq=10;
 175           default:
 176             ;
 177           }
 178
 179         if (irq<Q40_IRQ_SAMPLE)
 180           {
 181             if (irq_tab[irq].dev_id != dev_id)
 182               printk("%s: Removing probably wrong IRQ %d from %s\n",
 183                      __FUNCTION__, irq, irq_tab[irq].devname);
 184
 185             irq_tab[irq].handler = q40_defhand;
 186             irq_tab[irq].flags   = 0;
 187             irq_tab[irq].dev_id  = NULL;
 188             /* irq_tab[irq].devname = NULL; */
 189             /* do not reset state !! */
 190           }
 191         else
 192           { /* == Q40_IRQ_SAMPLE */
 193             cpu_free_irq(4, dev_id);
 194             cpu_free_irq(6, dev_id);
 195           }
 196 }
 197
 198
 199 irqreturn_t q40_process_int (int level, struct pt_regs *fp)
 200 {
 201   printk("unexpected interrupt vec=%x, pc=%lx, d0=%lx, d0_orig=%lx, d1=%lx, d2=%lx\n",
 202           level, fp->pc, fp->d0, fp->orig_d0, fp->d1, fp->d2);
 203   printk("\tIIRQ_REG = %x, EIRQ_REG = %x\n",master_inb(IIRQ_REG),master_inb(EIRQ_REG));
 204   return IRQ_HANDLED;
 205 }
 206
 207 /*
 208  * this stuff doesn't really belong here..
 209 */
 210
 211 int ql_ticks;              /* 200Hz ticks since last jiffie */
 212 static int sound_ticks;
 213
 214 #define SVOL 45
 215
 216 void q40_mksound(unsigned int hz, unsigned int ticks)
 217 {
 218   /* for now ignore hz, except that hz==0 switches off sound */
 219   /* simply alternate the ampl (128-SVOL)-(128+SVOL)-..-.. at 200Hz */
 220   if (hz==0)
 221     {
 222       if (sound_ticks)
 223         sound_ticks=1;
 224
 225       *DAC_LEFT=128;
 226       *DAC_RIGHT=128;
 227
 228       return;
 229     }
 230   /* sound itself is done in q40_timer_int */
 231   if (sound_ticks == 0) sound_ticks=1000; /* pretty long beep */
 232   sound_ticks=ticks<<1;
 233 }
 234
 235 static irqreturn_t (*q40_timer_routine)(int, void *, struct pt_regs *);
 236
 237 static irqreturn_t q40_timer_int (int irq, void * dev, struct pt_regs * regs)
 238 {
 239     ql_ticks = ql_ticks ? 0 : 1;
 240     if (sound_ticks)
 241       {
 242         unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL;
 243         sound_ticks--;
 244         *DAC_LEFT=sval;
 245         *DAC_RIGHT=sval;
 246       }
 247
 248     if (!ql_ticks)
 249         q40_timer_routine(irq, dev, regs);
 250     return IRQ_HANDLED;
 251 }
 252
 253 void q40_sched_init (irqreturn_t (*timer_routine)(int, void *, struct pt_regs *))
 254 {
 255     int timer_irq;
 256
 257     q40_timer_routine = timer_routine;
 258     timer_irq=Q40_IRQ_FRAME;
 259
 260     if (request_irq(timer_irq, q40_timer_int, 0,
 261                                 "timer", q40_timer_int))
 262         panic ("Couldn't register timer int");
 263
 264     master_outb(-1,FRAME_CLEAR_REG);
 265     master_outb( 1,FRAME_RATE_REG);
 266 }
 267
 268
 269 /*
 270  * tables to translate bits into IRQ numbers
 271  * it is a good idea to order the entries by priority
 272  *
 273 */
 274
 275 struct IRQ_TABLE{ unsigned mask; int irq ;};
 276 #if 0
 277 static struct IRQ_TABLE iirqs[]={
 278   {Q40_IRQ_FRAME_MASK,Q40_IRQ_FRAME},
 279   {Q40_IRQ_KEYB_MASK,Q40_IRQ_KEYBOARD},
 280   {0,0}};
 281 #endif
 282 static struct IRQ_TABLE eirqs[] = {
 283   { .mask = Q40_IRQ3_MASK,      .irq = 3 },     /* ser 1 */
 284   { .mask = Q40_IRQ4_MASK,      .irq = 4 },     /* ser 2 */
 285   { .mask = Q40_IRQ14_MASK,     .irq = 14 },    /* IDE 1 */
 286   { .mask = Q40_IRQ15_MASK,     .irq = 15 },    /* IDE 2 */
 287   { .mask = Q40_IRQ6_MASK,      .irq = 6 },     /* floppy, handled elsewhere */
 288   { .mask = Q40_IRQ7_MASK,      .irq = 7 },     /* par */
 289   { .mask = Q40_IRQ5_MASK,      .irq = 5 },
 290   { .mask = Q40_IRQ10_MASK,     .irq = 10 },
 291   {0,0}
 292 };
 293
 294 /* complain only this many times about spurious ints : */
 295 static int ccleirq=60;    /* ISA dev IRQ's*/
 296 /*static int cclirq=60;*/     /* internal */
 297
 298 /* FIXME: add shared ints,mask,unmask,probing.... */
 299
 300 #define IRQ_INPROGRESS 1
 301 /*static unsigned short saved_mask;*/
 302 //static int do_tint=0;
 303
 304 #define DEBUG_Q40INT
 305 /*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */
 306
 307 static int mext_disabled=0;  /* ext irq disabled by master chip? */
 308 static int aliased_irq=0;  /* how many times inside handler ?*/
 309
 310
 311 /* got level 2 interrupt, dispatch to ISA or keyboard/timer IRQs */
 312 irqreturn_t q40_irq2_handler (int vec, void *devname, struct pt_regs *fp)
 313 {
 314   unsigned mir, mer;
 315   int irq,i;
 316
 317 //repeat:
 318   mir=master_inb(IIRQ_REG);
 319   if (mir&Q40_IRQ_FRAME_MASK) {
 320           irq_tab[Q40_IRQ_FRAME].count++;
 321           irq_tab[Q40_IRQ_FRAME].handler(Q40_IRQ_FRAME,irq_tab[Q40_IRQ_FRAME].dev_id,fp);
 322           master_outb(-1,FRAME_CLEAR_REG);
 323   }
 324   if ((mir&Q40_IRQ_SER_MASK) || (mir&Q40_IRQ_EXT_MASK)) {
 325           mer=master_inb(EIRQ_REG);
 326           for (i=0; eirqs[i].mask; i++) {
 327                   if (mer&(eirqs[i].mask)) {
 328                           irq=eirqs[i].irq;
 329 /*
 330  * There is a little mess wrt which IRQ really caused this irq request. The
 331  * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they
 332  * are read - which is long after the request came in. In theory IRQs should
 333  * not just go away but they occassionally do
 334  */
 335                           if (irq>4 && irq<=15 && mext_disabled) {
 336                                   /*aliased_irq++;*/
 337                                   goto iirq;
 338                           }
 339                           if (irq_tab[irq].handler == q40_defhand ) {
 340                                   printk("handler for IRQ %d not defined\n",irq);
 341                                   continue; /* ignore uninited INTs :-( */
 342                           }
 343                           if ( irq_tab[irq].state & IRQ_INPROGRESS ) {
 344                                   /* some handlers do local_irq_enable() for irq latency reasons, */
 345                                   /* however reentering an active irq handler is not permitted */
 346 #ifdef IP_USE_DISABLE
 347                                   /* in theory this is the better way to do it because it still */
 348                                   /* lets through eg the serial irqs, unfortunately it crashes */
 349                                   disable_irq(irq);
 350                                   disabled=1;
 351 #else
 352                                   /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n",irq,disabled ? "already" : "not yet"); */
 353                                   fp->sr = (((fp->sr) & (~0x700))+0x200);
 354                                   disabled=1;
 355 #endif
 356                                   goto iirq;
 357                           }
 358                           irq_tab[irq].count++;
 359                           irq_tab[irq].state |= IRQ_INPROGRESS;
 360                           irq_tab[irq].handler(irq,irq_tab[irq].dev_id,fp);
 361                           irq_tab[irq].state &= ~IRQ_INPROGRESS;
 362
 363                           /* naively enable everything, if that fails than    */
 364                           /* this function will be reentered immediately thus */
 365                           /* getting another chance to disable the IRQ        */
 366
 367                           if ( disabled ) {
 368 #ifdef IP_USE_DISABLE
 369                                   if (irq>4){
 370                                           disabled=0;
 371                                           enable_irq(irq);}
 372 #else
 373                                   disabled=0;
 374                                   /*printk("reenabling irq %d\n",irq); */
 375 #endif
 376                           }
 377 // used to do 'goto repeat;' here, this delayed bh processing too long
 378                           return IRQ_HANDLED;
 379                   }
 380           }
 381           if (mer && ccleirq>0 && !aliased_irq)
 382                   printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer),ccleirq--;
 383   }
 384  iirq:
 385   mir=master_inb(IIRQ_REG);
 386   /* should test whether keyboard irq is really enabled, doing it in defhand */
 387   if (mir&Q40_IRQ_KEYB_MASK) {
 388           irq_tab[Q40_IRQ_KEYBOARD].count++;
 389           irq_tab[Q40_IRQ_KEYBOARD].handler(Q40_IRQ_KEYBOARD,irq_tab[Q40_IRQ_KEYBOARD].dev_id,fp);
 390   }
 391   return IRQ_HANDLED;
 392 }
 393
 394 int show_q40_interrupts (struct seq_file *p, void *v)
 395 {
 396         int i;
 397
 398         for (i = 0; i <= Q40_IRQ_MAX; i++) {
 399                 if (irq_tab[i].count)
 400                       seq_printf(p, "%sIRQ %02d: %8d  %s%s\n",
 401                               (i<=15) ? "ISA-" : "    " ,
 402                             i, irq_tab[i].count,
 403                             irq_tab[i].devname[0] ? irq_tab[i].devname : "?",
 404                             irq_tab[i].handler == q40_defhand ?
 405                                         " (now unassigned)" : "");
 406         }
 407         return 0;
 408 }
 409
 410
 411 static irqreturn_t q40_defhand (int irq, void *dev_id, struct pt_regs *fp)
 412 {
 413         if (irq!=Q40_IRQ_KEYBOARD)
 414              printk ("Unknown q40 interrupt %d\n", irq);
 415         else master_outb(-1,KEYBOARD_UNLOCK_REG);
 416         return IRQ_NONE;
 417 }
 418 static irqreturn_t default_handler(int lev, void *dev_id, struct pt_regs *regs)
 419 {
 420         printk ("Uninitialised interrupt level %d\n", lev);
 421         return IRQ_NONE;
 422 }
 423
 424 irqreturn_t (*q40_default_handler[SYS_IRQS])(int, void *, struct pt_regs *) = {
 425          [0] = default_handler,
 426          [1] = default_handler,
 427          [2] = default_handler,
 428          [3] = default_handler,
 429          [4] = default_handler,
 430          [5] = default_handler,
 431          [6] = default_handler,
 432          [7] = default_handler
 433 };
 434
 435
 436 void q40_enable_irq (unsigned int irq)
 437 {
 438   if ( irq>=5 && irq<=15 )
 439   {
 440     mext_disabled--;
 441     if (mext_disabled>0)
 442           printk("q40_enable_irq : nested disable/enable\n");
 443     if (mext_disabled==0)
 444     master_outb(1,EXT_ENABLE_REG);
 445     }
 446 }
 447
 448
 449 void q40_disable_irq (unsigned int irq)
 450 {
 451   /* disable ISA iqs : only do something if the driver has been
 452    * verified to be Q40 "compatible" - right now IDE, NE2K
 453    * Any driver should not attempt to sleep across disable_irq !!
 454    */
 455
 456   if ( irq>=5 && irq<=15 ) {
 457     master_outb(0,EXT_ENABLE_REG);
 458     mext_disabled++;
 459     if (mext_disabled>1) printk("disable_irq nesting count %d\n",mext_disabled);
 460   }
 461 }
 462
 463 unsigned long q40_probe_irq_on (void)
 464 {
 465   printk("irq probing not working - reconfigure the driver to avoid this\n");
 466   return -1;
 467 }
 468 int q40_probe_irq_off (unsigned long irqs)
 469 {
 470   return -1;
 471 }
 472 /*
 473  * Local variables:
 474  * compile-command: "m68k-linux-gcc -D__KERNEL__ -I/home/rz/lx/linux-2.2.6/include -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -pipe -fno-strength-reduce -ffixed-a2 -m68040   -c -o q40ints.o q40ints.c"
 475  * End:
 476  */