a8a5ce8b18fc9fdef5dbd2622573030c45dc1688
[linux-3.10.git] / 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/interrupt.h>
18
19 #include <asm/ptrace.h>
20 #include <asm/system.h>
21 #include <asm/irq.h>
22 #include <asm/traps.h>
23
24 #include <asm/q40_master.h>
25 #include <asm/q40ints.h>
26
27 /*
28  * Q40 IRQs are defined as follows:
29  *            3,4,5,6,7,10,11,14,15 : ISA dev IRQs
30  *            16-31: reserved
31  *            32   : keyboard int
32  *            33   : frame int (50/200 Hz periodic timer)
33  *            34   : sample int (10/20 KHz periodic timer)
34  *
35 */
36
37 static void q40_irq_handler(unsigned int, struct pt_regs *fp);
38 static void q40_irq_enable(struct irq_data *data);
39 static void q40_irq_disable(struct irq_data *data);
40
41 unsigned short q40_ablecount[35];
42 unsigned short q40_state[35];
43
44 static unsigned int q40_irq_startup(struct irq_data *data)
45 {
46         unsigned int irq = data->irq;
47
48         /* test for ISA ints not implemented by HW */
49         switch (irq) {
50         case 1: case 2: case 8: case 9:
51         case 11: case 12: case 13:
52                 printk("%s: ISA IRQ %d not implemented by HW\n", __func__, irq);
53                 /* FIXME return -ENXIO; */
54         }
55         return 0;
56 }
57
58 static void q40_irq_shutdown(struct irq_data *data)
59 {
60 }
61
62 static struct irq_chip q40_irq_chip = {
63         .name           = "q40",
64         .irq_startup    = q40_irq_startup,
65         .irq_shutdown   = q40_irq_shutdown,
66         .irq_enable     = q40_irq_enable,
67         .irq_disable    = q40_irq_disable,
68 };
69
70 /*
71  * void q40_init_IRQ (void)
72  *
73  * Parameters:  None
74  *
75  * Returns:     Nothing
76  *
77  * This function is called during kernel startup to initialize
78  * the q40 IRQ handling routines.
79  */
80
81 static int disabled;
82
83 void __init q40_init_IRQ(void)
84 {
85         m68k_setup_irq_controller(&q40_irq_chip, handle_simple_irq, 1,
86                                   Q40_IRQ_MAX);
87
88         /* setup handler for ISA ints */
89         m68k_setup_auto_interrupt(q40_irq_handler);
90
91         m68k_irq_startup_irq(IRQ_AUTO_2);
92         m68k_irq_startup_irq(IRQ_AUTO_4);
93
94         /* now enable some ints.. */
95         master_outb(1, EXT_ENABLE_REG);  /* ISA IRQ 5-15 */
96
97         /* make sure keyboard IRQ is disabled */
98         master_outb(0, KEY_IRQ_ENABLE_REG);
99 }
100
101
102 /*
103  * this stuff doesn't really belong here..
104  */
105
106 int ql_ticks;              /* 200Hz ticks since last jiffie */
107 static int sound_ticks;
108
109 #define SVOL 45
110
111 void q40_mksound(unsigned int hz, unsigned int ticks)
112 {
113         /* for now ignore hz, except that hz==0 switches off sound */
114         /* simply alternate the ampl (128-SVOL)-(128+SVOL)-..-.. at 200Hz */
115         if (hz == 0) {
116                 if (sound_ticks)
117                         sound_ticks = 1;
118
119                 *DAC_LEFT = 128;
120                 *DAC_RIGHT = 128;
121
122                 return;
123         }
124         /* sound itself is done in q40_timer_int */
125         if (sound_ticks == 0)
126                 sound_ticks = 1000; /* pretty long beep */
127         sound_ticks = ticks << 1;
128 }
129
130 static irq_handler_t q40_timer_routine;
131
132 static irqreturn_t q40_timer_int (int irq, void * dev)
133 {
134         ql_ticks = ql_ticks ? 0 : 1;
135         if (sound_ticks) {
136                 unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL;
137                 sound_ticks--;
138                 *DAC_LEFT=sval;
139                 *DAC_RIGHT=sval;
140         }
141
142         if (!ql_ticks)
143                 q40_timer_routine(irq, dev);
144         return IRQ_HANDLED;
145 }
146
147 void q40_sched_init (irq_handler_t timer_routine)
148 {
149         int timer_irq;
150
151         q40_timer_routine = timer_routine;
152         timer_irq = Q40_IRQ_FRAME;
153
154         if (request_irq(timer_irq, q40_timer_int, 0,
155                                 "timer", q40_timer_int))
156                 panic("Couldn't register timer int");
157
158         master_outb(-1, FRAME_CLEAR_REG);
159         master_outb( 1, FRAME_RATE_REG);
160 }
161
162
163 /*
164  * tables to translate bits into IRQ numbers
165  * it is a good idea to order the entries by priority
166  *
167 */
168
169 struct IRQ_TABLE{ unsigned mask; int irq ;};
170 #if 0
171 static struct IRQ_TABLE iirqs[]={
172   {Q40_IRQ_FRAME_MASK,Q40_IRQ_FRAME},
173   {Q40_IRQ_KEYB_MASK,Q40_IRQ_KEYBOARD},
174   {0,0}};
175 #endif
176 static struct IRQ_TABLE eirqs[] = {
177   { .mask = Q40_IRQ3_MASK,      .irq = 3 },     /* ser 1 */
178   { .mask = Q40_IRQ4_MASK,      .irq = 4 },     /* ser 2 */
179   { .mask = Q40_IRQ14_MASK,     .irq = 14 },    /* IDE 1 */
180   { .mask = Q40_IRQ15_MASK,     .irq = 15 },    /* IDE 2 */
181   { .mask = Q40_IRQ6_MASK,      .irq = 6 },     /* floppy, handled elsewhere */
182   { .mask = Q40_IRQ7_MASK,      .irq = 7 },     /* par */
183   { .mask = Q40_IRQ5_MASK,      .irq = 5 },
184   { .mask = Q40_IRQ10_MASK,     .irq = 10 },
185   {0,0}
186 };
187
188 /* complain only this many times about spurious ints : */
189 static int ccleirq=60;    /* ISA dev IRQs*/
190 /*static int cclirq=60;*/     /* internal */
191
192 /* FIXME: add shared ints,mask,unmask,probing.... */
193
194 #define IRQ_INPROGRESS 1
195 /*static unsigned short saved_mask;*/
196 //static int do_tint=0;
197
198 #define DEBUG_Q40INT
199 /*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */
200
201 static int mext_disabled=0;  /* ext irq disabled by master chip? */
202 static int aliased_irq=0;  /* how many times inside handler ?*/
203
204
205 /* got interrupt, dispatch to ISA or keyboard/timer IRQs */
206 static void q40_irq_handler(unsigned int irq, struct pt_regs *fp)
207 {
208         unsigned mir, mer;
209         int i;
210
211 //repeat:
212         mir = master_inb(IIRQ_REG);
213 #ifdef CONFIG_BLK_DEV_FD
214         if ((mir & Q40_IRQ_EXT_MASK) &&
215             (master_inb(EIRQ_REG) & Q40_IRQ6_MASK)) {
216                 floppy_hardint();
217                 return;
218         }
219 #endif
220         switch (irq) {
221         case 4:
222         case 6:
223                 __m68k_handle_int(Q40_IRQ_SAMPLE, fp);
224                 return;
225         }
226         if (mir & Q40_IRQ_FRAME_MASK) {
227                 __m68k_handle_int(Q40_IRQ_FRAME, fp);
228                 master_outb(-1, FRAME_CLEAR_REG);
229         }
230         if ((mir & Q40_IRQ_SER_MASK) || (mir & Q40_IRQ_EXT_MASK)) {
231                 mer = master_inb(EIRQ_REG);
232                 for (i = 0; eirqs[i].mask; i++) {
233                         if (mer & eirqs[i].mask) {
234                                 irq = eirqs[i].irq;
235 /*
236  * There is a little mess wrt which IRQ really caused this irq request. The
237  * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they
238  * are read - which is long after the request came in. In theory IRQs should
239  * not just go away but they occasionally do
240  */
241                                 if (irq > 4 && irq <= 15 && mext_disabled) {
242                                         /*aliased_irq++;*/
243                                         goto iirq;
244                                 }
245                                 if (q40_state[irq] & IRQ_INPROGRESS) {
246                                         /* some handlers do local_irq_enable() for irq latency reasons, */
247                                         /* however reentering an active irq handler is not permitted */
248 #ifdef IP_USE_DISABLE
249                                         /* in theory this is the better way to do it because it still */
250                                         /* lets through eg the serial irqs, unfortunately it crashes */
251                                         disable_irq(irq);
252                                         disabled = 1;
253 #else
254                                         /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n",
255                                                 irq, disabled ? "already" : "not yet"); */
256                                         fp->sr = (((fp->sr) & (~0x700))+0x200);
257                                         disabled = 1;
258 #endif
259                                         goto iirq;
260                                 }
261                                 q40_state[irq] |= IRQ_INPROGRESS;
262                                 __m68k_handle_int(irq, fp);
263                                 q40_state[irq] &= ~IRQ_INPROGRESS;
264
265                                 /* naively enable everything, if that fails than    */
266                                 /* this function will be reentered immediately thus */
267                                 /* getting another chance to disable the IRQ        */
268
269                                 if (disabled) {
270 #ifdef IP_USE_DISABLE
271                                         if (irq > 4) {
272                                                 disabled = 0;
273                                                 enable_irq(irq);
274                                         }
275 #else
276                                         disabled = 0;
277                                         /*printk("reenabling irq %d\n", irq); */
278 #endif
279                                 }
280 // used to do 'goto repeat;' here, this delayed bh processing too long
281                                 return;
282                         }
283                 }
284                 if (mer && ccleirq > 0 && !aliased_irq) {
285                         printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer);
286                         ccleirq--;
287                 }
288         }
289  iirq:
290         mir = master_inb(IIRQ_REG);
291         /* should test whether keyboard irq is really enabled, doing it in defhand */
292         if (mir & Q40_IRQ_KEYB_MASK)
293                 __m68k_handle_int(Q40_IRQ_KEYBOARD, fp);
294
295         return;
296 }
297
298 void q40_irq_enable(struct irq_data *data)
299 {
300         unsigned int irq = data->irq;
301
302         if (irq >= 5 && irq <= 15) {
303                 mext_disabled--;
304                 if (mext_disabled > 0)
305                         printk("q40_irq_enable : nested disable/enable\n");
306                 if (mext_disabled == 0)
307                         master_outb(1, EXT_ENABLE_REG);
308         }
309 }
310
311
312 void q40_irq_disable(struct irq_data *data)
313 {
314         unsigned int irq = data->irq;
315
316         /* disable ISA iqs : only do something if the driver has been
317          * verified to be Q40 "compatible" - right now IDE, NE2K
318          * Any driver should not attempt to sleep across disable_irq !!
319          */
320
321         if (irq >= 5 && irq <= 15) {
322                 master_outb(0, EXT_ENABLE_REG);
323                 mext_disabled++;
324                 if (mext_disabled > 1)
325                         printk("disable_irq nesting count %d\n",mext_disabled);
326         }
327 }
328
329 unsigned long q40_probe_irq_on(void)
330 {
331         printk("irq probing not working - reconfigure the driver to avoid this\n");
332         return -1;
333 }
334 int q40_probe_irq_off(unsigned long irqs)
335 {
336         return -1;
337 }