xref: /openbmc/linux/arch/m68k/q40/q40ints.c (revision 1da177e4)
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  */
477