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 losely based on bvme6000ints.c
  11  *
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/types.h>
  16 #include <linux/kernel.h>
  17 #include <linux/errno.h>
  18 #include <linux/string.h>
  19 #include <linux/sched.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/interrupt.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/hardirq.h>
  28 #include <asm/traps.h>
  29
  30 #include <asm/q40_master.h>
  31 #include <asm/q40ints.h>
  32
  33 /*
  34  * Q40 IRQs are defined as follows:
  35  *            3,4,5,6,7,10,11,14,15 : ISA dev IRQs
  36  *            16-31: reserved
  37  *            32   : keyboard int
  38  *            33   : frame int (50/200 Hz periodic timer)
  39  *            34   : sample int (10/20 KHz periodic timer)
  40  *
  41 */
  42
  43 extern int ints_inited;
  44
  45
  46 void q40_irq2_handler (int, void *, struct pt_regs *fp);
  47
  48
  49 extern void (*q40_sys_default_handler[]) (int, void *, struct pt_regs *);
  50
  51 static void q40_defhand (int irq, void *dev_id, struct pt_regs *fp);
  52 static void sys_default_handler(int lev, void *dev_id, struct pt_regs *regs);
  53
  54
  55 #define DEVNAME_SIZE 24
  56
  57 static struct q40_irq_node {
  58         void            (*handler)(int, void *, struct pt_regs *);
  59         unsigned long   flags;
  60         void            *dev_id;
  61   /*        struct q40_irq_node *next;*/
  62         char            devname[DEVNAME_SIZE];
  63         unsigned        count;
  64         unsigned short  state;
  65 } irq_tab[Q40_IRQ_MAX+1];
  66
  67 short unsigned q40_ablecount[Q40_IRQ_MAX+1];
  68
  69 /*
  70  * void q40_init_IRQ (void)
  71  *
  72  * Parameters:  None
  73  *
  74  * Returns:     Nothing
  75  *
  76  * This function is called during kernel startup to initialize
  77  * the q40 IRQ handling routines.
  78  */
  79
  80 static int disabled=0;
  81
  82 void q40_init_IRQ (void)
  83 {
  84         int i;
  85
  86         disabled=0;
  87         for (i = 0; i <= Q40_IRQ_MAX; i++) {
  88                 irq_tab[i].handler = q40_defhand;
  89                 irq_tab[i].flags = 0;
  90                 irq_tab[i].dev_id = NULL;
  91                 /*              irq_tab[i].next = NULL;*/
  92                 irq_tab[i].devname[0] = 0;
  93                 irq_tab[i].count = 0;
  94                 irq_tab[i].state =0;
  95                 q40_ablecount[i]=0;   /* all enabled */
  96         }
  97
  98         /* setup handler for ISA ints */
  99         sys_request_irq(IRQ2,q40_irq2_handler, 0, "q40 ISA and master chip", NULL);
 100
 101         /* now enable some ints.. */
 102         master_outb(1,EXT_ENABLE_REG);  /* ISA IRQ 5-15 */
 103
 104         /* make sure keyboard IRQ is disabled */
 105         master_outb(0,KEY_IRQ_ENABLE_REG);
 106 }
 107
 108 int q40_request_irq(unsigned int irq,
 109                 void (*handler)(int, void *, struct pt_regs *),
 110                 unsigned long flags, const char *devname, void *dev_id)
 111 {
 112   /*printk("q40_request_irq %d, %s\n",irq,devname);*/
 113
 114         if (irq > Q40_IRQ_MAX || (irq>15 && irq<32)) {
 115                 printk("%s: Incorrect IRQ %d from %s\n", __FUNCTION__, irq, devname);
 116                 return -ENXIO;
 117         }
 118
 119         /* test for ISA ints not implemented by HW */
 120         switch (irq)
 121           {
 122           case 1: case 2: case 8: case 9:
 123           case 12: case 13:
 124             printk("%s: ISA IRQ %d from %s not implemented by HW\n", __FUNCTION__, irq, devname);
 125             return -ENXIO;
 126           case 11:
 127             printk("warning IRQ 10 and 11 not distinguishable\n");
 128             irq=10;
 129           default:
 130           }
 131
 132         if (irq<Q40_IRQ_SAMPLE)
 133           {
 134             if (irq_tab[irq].dev_id != NULL)
 135                   {
 136                     printk("%s: IRQ %d from %s is not replaceable\n",
 137                            __FUNCTION__, irq, irq_tab[irq].devname);
 138                     return -EBUSY;
 139                   }
 140             /*printk("IRQ %d set to handler %p\n",irq,handler);*/
 141             if (dev_id==NULL)
 142                   {
 143                 printk("WARNING: dev_id == NULL in request_irq\n");
 144                 dev_id=(void*)1;
 145               }
 146             irq_tab[irq].handler = handler;
 147             irq_tab[irq].flags   = flags;
 148             irq_tab[irq].dev_id  = dev_id;
 149             strncpy(irq_tab[irq].devname,devname,DEVNAME_SIZE);
 150             irq_tab[irq].state = 0;
 151             return 0;
 152           }
 153         else {
 154           /* Q40_IRQ_SAMPLE :somewhat special actions required here ..*/
 155           sys_request_irq(4,handler,flags,devname,dev_id);
 156           sys_request_irq(6,handler,flags,devname,dev_id);
 157           return 0;
 158         }
 159 }
 160
 161 void q40_free_irq(unsigned int irq, void *dev_id)
 162 {
 163         if (irq > Q40_IRQ_MAX || (irq>15 && irq<32)) {
 164                 printk("%s: Incorrect IRQ %d, dev_id %x \n", __FUNCTION__, irq, (unsigned)dev_id);
 165                 return;
 166         }
 167
 168         /* test for ISA ints not implemented by HW */
 169         switch (irq)
 170           {
 171           case 1: case 2: case 8: case 9:
 172           case 12: case 13:
 173             printk("%s: ISA IRQ %d from %x illegal\n", __FUNCTION__, irq, (unsigned)dev_id);
 174             return;
 175           case 11: irq=10;
 176           default:
 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             sys_free_irq(4,dev_id);
 194             sys_free_irq(6,dev_id);
 195           }
 196 }
 197
 198
 199 void q40_process_int (int level, struct pt_regs *fp)
 200 {
 201   printk("unexpected interrupt %x\n",level);
 202 }
 203
 204 /*
 205  * this stuff doesn't really belong here..
 206 */
 207
 208 int ql_ticks;              /* 200Hz ticks since last jiffie */
 209 static int sound_ticks;
 210
 211 #define SVOL 45
 212
 213 void q40_mksound(unsigned int hz, unsigned int ticks)
 214 {
 215   /* for now ignore hz, except that hz==0 switches off sound */
 216   /* simply alternate the ampl (128-SVOL)-(128+SVOL)-..-.. at 200Hz */
 217   if (hz==0)
 218     {
 219       if (sound_ticks)
 220         sound_ticks=1;
 221
 222       *DAC_LEFT=128;
 223       *DAC_RIGHT=128;
 224
 225       return;
 226     }
 227   /* sound itself is done in q40_timer_int */
 228   if (sound_ticks == 0) sound_ticks=1000; /* pretty long beep */
 229   sound_ticks=ticks<<1;
 230 }
 231
 232 static void (*q40_timer_routine)(int, void *, struct pt_regs *);
 233
 234 static void q40_timer_int (int irq, void * dev, struct pt_regs * regs)
 235 {
 236     ql_ticks = ql_ticks ? 0 : 1;
 237     if (sound_ticks)
 238       {
 239         unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL;
 240         sound_ticks--;
 241         *DAC_LEFT=sval;
 242         *DAC_RIGHT=sval;
 243       }
 244
 245     if (ql_ticks) return;
 246
 247     q40_timer_routine(irq, dev, regs);
 248 }
 249
 250 void q40_sched_init (void (*timer_routine)(int, void *, struct pt_regs *))
 251 {
 252     int timer_irq;
 253
 254     q40_timer_routine = timer_routine;
 255     timer_irq=Q40_IRQ_FRAME;
 256
 257     if (request_irq(timer_irq, q40_timer_int, 0,
 258                                 "timer", q40_timer_int))
 259         panic ("Couldn't register timer int");
 260
 261     master_outb(-1,FRAME_CLEAR_REG);
 262     master_outb( 1,FRAME_RATE_REG);
 263 }
 264
 265
 266 /*
 267  * tables to translate bits into IRQ numbers
 268  * it is a good idea to order the entries by priority
 269  *
 270 */
 271
 272 struct IRQ_TABLE{ unsigned mask; int irq ;};
 273 #if 0
 274 static struct IRQ_TABLE iirqs[]={
 275   {Q40_IRQ_FRAME_MASK,Q40_IRQ_FRAME},
 276   {Q40_IRQ_KEYB_MASK,Q40_IRQ_KEYBOARD},
 277   {0,0}};
 278 #endif
 279 static struct IRQ_TABLE eirqs[]={
 280   {Q40_IRQ3_MASK,3},                   /* ser 1 */
 281   {Q40_IRQ4_MASK,4},                   /* ser 2 */
 282   {Q40_IRQ14_MASK,14},                 /* IDE 1 */
 283   {Q40_IRQ15_MASK,15},                 /* IDE 2 */
 284   {Q40_IRQ6_MASK,6},                   /* floppy, handled elsewhere */
 285   {Q40_IRQ7_MASK,7},                   /* par */
 286
 287   {Q40_IRQ5_MASK,5},
 288   {Q40_IRQ10_MASK,10},
 289
 290
 291
 292
 293   {0,0}};
 294
 295 /* complain only this many times about spurious ints : */
 296 static int ccleirq=60;    /* ISA dev IRQ's*/
 297 /*static int cclirq=60;*/     /* internal */
 298
 299 /* FIXME: add shared ints,mask,unmask,probing.... */
 300
 301 #define IRQ_INPROGRESS 1
 302 /*static unsigned short saved_mask;*/
 303 //static int do_tint=0;
 304
 305 #define DEBUG_Q40INT
 306 /*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */
 307
 308 static int mext_disabled=0;  /* ext irq disabled by master chip? */
 309 static int aliased_irq=0;  /* how many times inside handler ?*/
 310
 311
 312 /* got level 2 interrupt, dispatch to ISA or keyboard/timer IRQs */
 313 void q40_irq2_handler (int vec, void *devname, struct pt_regs *fp)
 314 {
 315   unsigned mir, mer;
 316   int irq,i;
 317
 318  repeat:
 319   mir=master_inb(IIRQ_REG);
 320   if (mir&Q40_IRQ_FRAME_MASK) {
 321           irq_tab[Q40_IRQ_FRAME].count++;
 322           irq_tab[Q40_IRQ_FRAME].handler(Q40_IRQ_FRAME,irq_tab[Q40_IRQ_FRAME].dev_id,fp);
 323           master_outb(-1,FRAME_CLEAR_REG);
 324   }
 325   if ((mir&Q40_IRQ_SER_MASK) || (mir&Q40_IRQ_EXT_MASK)) {
 326           mer=master_inb(EIRQ_REG);
 327           for (i=0; eirqs[i].mask; i++) {
 328                   if (mer&(eirqs[i].mask)) {
 329                           irq=eirqs[i].irq;
 330 /*
 331  * There is a little mess wrt which IRQ really caused this irq request. The
 332  * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they
 333  * are read - which is long after the request came in. In theory IRQs should
 334  * not just go away but they occassionally do
 335  */
 336                           if (irq>4 && irq<=15 && mext_disabled) {
 337                                   /*aliased_irq++;*/
 338                                   goto iirq;
 339                           }
 340                           if (irq_tab[irq].handler == q40_defhand ) {
 341                                   printk("handler for IRQ %d not defined\n",irq);
 342                                   continue; /* ignore uninited INTs :-( */
 343                           }
 344                           if ( irq_tab[irq].state & IRQ_INPROGRESS ) {
 345                                   /* some handlers do sti() for irq latency reasons, */
 346                                   /* however reentering an active irq handler is not permitted */
 347 #ifdef IP_USE_DISABLE
 348                                   /* in theory this is the better way to do it because it still */
 349                                   /* lets through eg the serial irqs, unfortunately it crashes */
 350                                   disable_irq(irq);
 351                                   disabled=1;
 352 #else
 353                                   /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n",irq,disabled ? "already" : "not yet"); */
 354                                   fp->sr = (((fp->sr) & (~0x700))+0x200);
 355                                   disabled=1;
 356 #endif
 357                                   goto iirq;
 358                           }
 359                           irq_tab[irq].count++;
 360                           irq_tab[irq].state |= IRQ_INPROGRESS;
 361                           irq_tab[irq].handler(irq,irq_tab[irq].dev_id,fp);
 362                           irq_tab[irq].state &= ~IRQ_INPROGRESS;
 363
 364                           /* naively enable everything, if that fails than    */
 365                           /* this function will be reentered immediately thus */
 366                           /* getting another chance to disable the IRQ        */
 367
 368                           if ( disabled ) {
 369 #ifdef IP_USE_DISABLE
 370                                   if (irq>4){
 371                                           disabled=0;
 372                                           enable_irq(irq);}
 373 #else
 374                                   disabled=0;
 375                                   /*printk("reenabling irq %d\n",irq); */
 376 #endif
 377                           }
 378 // used to do 'goto repeat;' her, this delayed bh processing too long
 379                           return;
 380                   }
 381           }
 382           if (mer && ccleirq>0 && !aliased_irq)
 383                   printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer),ccleirq--;
 384   }
 385  iirq:
 386   mir=master_inb(IIRQ_REG);
 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 }
 392
 393 int show_q40_interrupts (struct seq_file *p, void *v)
 394 {
 395         int i;
 396
 397         for (i = 0; i <= Q40_IRQ_MAX; i++) {
 398                 if (irq_tab[i].count)
 399                       seq_printf(p, "%sIRQ %02d: %8d  %s%s\n",
 400                               (i<=15) ? "ISA-" : "    " ,
 401                             i, irq_tab[i].count,
 402                             irq_tab[i].devname[0] ? irq_tab[i].devname : "?",
 403                             irq_tab[i].handler == q40_defhand ?
 404                                         " (now unassigned)" : "");
 405         }
 406         return 0;
 407 }
 408
 409
 410 static void q40_defhand (int irq, void *dev_id, struct pt_regs *fp)
 411 {
 412         printk ("Unknown q40 interrupt 0x%02x\n", irq);
 413 }
 414 static void sys_default_handler(int lev, void *dev_id, struct pt_regs *regs)
 415 {
 416         printk ("Uninitialised interrupt level %d\n", lev);
 417 }
 418
 419  void (*q40_sys_default_handler[SYS_IRQS]) (int, void *, struct pt_regs *) = {
 420          sys_default_handler,sys_default_handler,sys_default_handler,sys_default_handler,
 421          sys_default_handler,sys_default_handler,sys_default_handler,sys_default_handler
 422  };
 423
 424
 425 void q40_enable_irq (unsigned int irq)
 426 {
 427   if ( irq>=5 && irq<=15 )
 428   {
 429     mext_disabled--;
 430     if (mext_disabled>0)
 431           printk("q40_enable_irq : nested disable/enable\n");
 432     if (mext_disabled==0)
 433     master_outb(1,EXT_ENABLE_REG);
 434     }
 435 }
 436
 437
 438 void q40_disable_irq (unsigned int irq)
 439 {
 440   /* disable ISA iqs : only do something if the driver has been
 441    * verified to be Q40 "compatible" - right now IDE, NE2K
 442    * Any driver should not attempt to sleep accross disable_irq !!
 443    */
 444
 445   if ( irq>=5 && irq<=15 ) {
 446     master_outb(0,EXT_ENABLE_REG);
 447     mext_disabled++;
 448     if (mext_disabled>1) printk("disable_irq nesting count %d\n",mext_disabled);
 449   }
 450 }
 451
 452 unsigned long q40_probe_irq_on (void)
 453 {
 454   printk("irq probing not working - reconfigure the driver to avoid this\n");
 455   return -1;
 456 }
 457 int q40_probe_irq_off (unsigned long irqs)
 458 {
 459   return -1;
 460 }
 461 /*
 462  * Local variables:
 463  * 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"
 464  * End:
 465  */