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 37static void q40_irq_handler(unsigned int, struct pt_regs *fp); 38static void q40_enable_irq(unsigned int); 39static void q40_disable_irq(unsigned int); 40 41unsigned short q40_ablecount[35]; 42unsigned short q40_state[35]; 43 44static int q40_irq_startup(unsigned int irq) 45{ 46 /* test for ISA ints not implemented by HW */ 47 switch (irq) { 48 case 1: case 2: case 8: case 9: 49 case 11: case 12: case 13: 50 printk("%s: ISA IRQ %d not implemented by HW\n", __FUNCTION__, irq); 51 return -ENXIO; 52 } 53 return 0; 54} 55 56static void q40_irq_shutdown(unsigned int irq) 57{ 58} 59 60static struct irq_controller q40_irq_controller = { 61 .name = "q40", 62 .lock = __SPIN_LOCK_UNLOCKED(q40_irq_controller.lock), 63 .startup = q40_irq_startup, 64 .shutdown = q40_irq_shutdown, 65 .enable = q40_enable_irq, 66 .disable = q40_disable_irq, 67}; 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 80static int disabled; 81 82void q40_init_IRQ(void) 83{ 84 m68k_setup_irq_controller(&q40_irq_controller, 1, Q40_IRQ_MAX); 85 86 /* setup handler for ISA ints */ 87 m68k_setup_auto_interrupt(q40_irq_handler); 88 89 m68k_irq_startup(IRQ_AUTO_2); 90 m68k_irq_startup(IRQ_AUTO_4); 91 92 /* now enable some ints.. */ 93 master_outb(1, EXT_ENABLE_REG); /* ISA IRQ 5-15 */ 94 95 /* make sure keyboard IRQ is disabled */ 96 master_outb(0, KEY_IRQ_ENABLE_REG); 97} 98 99 100/* 101 * this stuff doesn't really belong here.. 102 */ 103 104int ql_ticks; /* 200Hz ticks since last jiffie */ 105static int sound_ticks; 106 107#define SVOL 45 108 109void q40_mksound(unsigned int hz, unsigned int ticks) 110{ 111 /* for now ignore hz, except that hz==0 switches off sound */ 112 /* simply alternate the ampl (128-SVOL)-(128+SVOL)-..-.. at 200Hz */ 113 if (hz == 0) { 114 if (sound_ticks) 115 sound_ticks = 1; 116 117 *DAC_LEFT = 128; 118 *DAC_RIGHT = 128; 119 120 return; 121 } 122 /* sound itself is done in q40_timer_int */ 123 if (sound_ticks == 0) 124 sound_ticks = 1000; /* pretty long beep */ 125 sound_ticks = ticks << 1; 126} 127 128static irq_handler_t q40_timer_routine; 129 130static irqreturn_t q40_timer_int (int irq, void * dev) 131{ 132 ql_ticks = ql_ticks ? 0 : 1; 133 if (sound_ticks) { 134 unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL; 135 sound_ticks--; 136 *DAC_LEFT=sval; 137 *DAC_RIGHT=sval; 138 } 139 140 if (!ql_ticks) 141 q40_timer_routine(irq, dev); 142 return IRQ_HANDLED; 143} 144 145void q40_sched_init (irq_handler_t timer_routine) 146{ 147 int timer_irq; 148 149 q40_timer_routine = timer_routine; 150 timer_irq = Q40_IRQ_FRAME; 151 152 if (request_irq(timer_irq, q40_timer_int, 0, 153 "timer", q40_timer_int)) 154 panic("Couldn't register timer int"); 155 156 master_outb(-1, FRAME_CLEAR_REG); 157 master_outb( 1, FRAME_RATE_REG); 158} 159 160 161/* 162 * tables to translate bits into IRQ numbers 163 * it is a good idea to order the entries by priority 164 * 165*/ 166 167struct IRQ_TABLE{ unsigned mask; int irq ;}; 168static struct IRQ_TABLE eirqs[] = { 169 { .mask = Q40_IRQ3_MASK, .irq = 3 }, /* ser 1 */ 170 { .mask = Q40_IRQ4_MASK, .irq = 4 }, /* ser 2 */ 171 { .mask = Q40_IRQ14_MASK, .irq = 14 }, /* IDE 1 */ 172 { .mask = Q40_IRQ15_MASK, .irq = 15 }, /* IDE 2 */ 173 { .mask = Q40_IRQ6_MASK, .irq = 6 }, /* floppy, handled elsewhere */ 174 { .mask = Q40_IRQ7_MASK, .irq = 7 }, /* par */ 175 { .mask = Q40_IRQ5_MASK, .irq = 5 }, 176 { .mask = Q40_IRQ10_MASK, .irq = 10 }, 177 {0,0} 178}; 179 180/* complain only this many times about spurious ints : */ 181static int ccleirq=60; /* ISA dev IRQ's*/ 182/*static int cclirq=60;*/ /* internal */ 183 184 185#define IRQ_INPROGRESS 1 186/*static unsigned short saved_mask;*/ 187//static int do_tint=0; 188 189#define DEBUG_Q40INT 190/*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */ 191 192static int mext_disabled=0; /* ext irq disabled by master chip? */ 193static int aliased_irq=0; /* how many times inside handler ?*/ 194 195 196/* got interrupt, dispatch to ISA or keyboard/timer IRQs */ 197static void q40_irq_handler(unsigned int irq, struct pt_regs *fp) 198{ 199 unsigned mir, mer; 200 int i; 201 202//repeat: 203 mir = master_inb(IIRQ_REG); 204#ifdef CONFIG_BLK_DEV_FD 205 if ((mir & Q40_IRQ_EXT_MASK) && 206 (master_inb(EIRQ_REG) & Q40_IRQ6_MASK)) { 207 floppy_hardint(); 208 return; 209 } 210#endif 211 switch (irq) { 212 case 4: 213 case 6: 214 __m68k_handle_int(Q40_IRQ_SAMPLE, fp); 215 return; 216 } 217 if (mir & Q40_IRQ_FRAME_MASK) { 218 __m68k_handle_int(Q40_IRQ_FRAME, fp); 219 master_outb(-1, FRAME_CLEAR_REG); 220 } 221 if ((mir & Q40_IRQ_SER_MASK) || (mir & Q40_IRQ_EXT_MASK)) { 222 mer = master_inb(EIRQ_REG); 223 for (i = 0; eirqs[i].mask; i++) { 224 if (mer & eirqs[i].mask) { 225 irq = eirqs[i].irq; 226/* 227 * There is a little mess wrt which IRQ really caused this irq request. The 228 * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they 229 * are read - which is long after the request came in. In theory IRQs should 230 * not just go away but they occassionally do 231 */ 232 if (irq > 4 && irq <= 15 && mext_disabled) { 233 /*aliased_irq++;*/ 234 goto iirq; 235 } 236 if (q40_state[irq] & IRQ_INPROGRESS) { 237 /* some handlers do local_irq_enable() for irq latency reasons, */ 238 /* however reentering an active irq handler is not permitted */ 239#ifdef IP_USE_DISABLE 240 /* in theory this is the better way to do it because it still */ 241 /* lets through eg the serial irqs, unfortunately it crashes */ 242 disable_irq(irq); 243 disabled = 1; 244#else 245 /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n", 246 irq, disabled ? "already" : "not yet"); */ 247 fp->sr = (((fp->sr) & (~0x700))+0x200); 248 disabled = 1; 249#endif 250 goto iirq; 251 } 252 q40_state[irq] |= IRQ_INPROGRESS; 253 __m68k_handle_int(irq, fp); 254 q40_state[irq] &= ~IRQ_INPROGRESS; 255 256 /* naively enable everything, if that fails than */ 257 /* this function will be reentered immediately thus */ 258 /* getting another chance to disable the IRQ */ 259 260 if (disabled) { 261#ifdef IP_USE_DISABLE 262 if (irq > 4) { 263 disabled = 0; 264 enable_irq(irq); 265 } 266#else 267 disabled = 0; 268 /*printk("reenabling irq %d\n", irq); */ 269#endif 270 } 271// used to do 'goto repeat;' here, this delayed bh processing too long 272 return; 273 } 274 } 275 if (mer && ccleirq > 0 && !aliased_irq) { 276 printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer); 277 ccleirq--; 278 } 279 } 280 iirq: 281 mir = master_inb(IIRQ_REG); 282 /* should test whether keyboard irq is really enabled, doing it in defhand */ 283 if (mir & Q40_IRQ_KEYB_MASK) 284 __m68k_handle_int(Q40_IRQ_KEYBOARD, fp); 285 286 return; 287} 288 289void q40_enable_irq(unsigned int irq) 290{ 291 if (irq >= 5 && irq <= 15) { 292 mext_disabled--; 293 if (mext_disabled > 0) 294 printk("q40_enable_irq : nested disable/enable\n"); 295 if (mext_disabled == 0) 296 master_outb(1, EXT_ENABLE_REG); 297 } 298} 299 300 301void q40_disable_irq(unsigned int irq) 302{ 303 /* disable ISA iqs : only do something if the driver has been 304 * verified to be Q40 "compatible" - right now IDE, NE2K 305 * Any driver should not attempt to sleep across disable_irq !! 306 */ 307 308 if (irq >= 5 && irq <= 15) { 309 master_outb(0, EXT_ENABLE_REG); 310 mext_disabled++; 311 if (mext_disabled > 1) 312 printk("disable_irq nesting count %d\n",mext_disabled); 313 } 314} 315 316unsigned long q40_probe_irq_on(void) 317{ 318 printk("irq probing not working - reconfigure the driver to avoid this\n"); 319 return -1; 320} 321int q40_probe_irq_off(unsigned long irqs) 322{ 323 return -1; 324} 325