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_enable_irq(unsigned int); 39 static void q40_disable_irq(unsigned int); 40 41 unsigned short q40_ablecount[35]; 42 unsigned short q40_state[35]; 43 44 static 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", __func__, irq); 51 return -ENXIO; 52 } 53 return 0; 54 } 55 56 static void q40_irq_shutdown(unsigned int irq) 57 { 58 } 59 60 static 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 80 static int disabled; 81 82 void __init 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 */ 103 104 int ql_ticks; /* 200Hz ticks since last jiffie */ 105 static int sound_ticks; 106 107 #define SVOL 45 108 109 void 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 } 127 128 static irq_handler_t q40_timer_routine; 129 130 static 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 } 144 145 void 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 */ 166 167 struct IRQ_TABLE{ unsigned mask; int irq ;}; 168 #if 0 169 static struct IRQ_TABLE iirqs[]={ 170 {Q40_IRQ_FRAME_MASK,Q40_IRQ_FRAME}, 171 {Q40_IRQ_KEYB_MASK,Q40_IRQ_KEYBOARD}, 172 {0,0}}; 173 #endif 174 static struct IRQ_TABLE eirqs[] = { 175 { .mask = Q40_IRQ3_MASK, .irq = 3 }, /* ser 1 */ 176 { .mask = Q40_IRQ4_MASK, .irq = 4 }, /* ser 2 */ 177 { .mask = Q40_IRQ14_MASK, .irq = 14 }, /* IDE 1 */ 178 { .mask = Q40_IRQ15_MASK, .irq = 15 }, /* IDE 2 */ 179 { .mask = Q40_IRQ6_MASK, .irq = 6 }, /* floppy, handled elsewhere */ 180 { .mask = Q40_IRQ7_MASK, .irq = 7 }, /* par */ 181 { .mask = Q40_IRQ5_MASK, .irq = 5 }, 182 { .mask = Q40_IRQ10_MASK, .irq = 10 }, 183 {0,0} 184 }; 185 186 /* complain only this many times about spurious ints : */ 187 static int ccleirq=60; /* ISA dev IRQs*/ 188 /*static int cclirq=60;*/ /* internal */ 189 190 /* FIXME: add shared ints,mask,unmask,probing.... */ 191 192 #define IRQ_INPROGRESS 1 193 /*static unsigned short saved_mask;*/ 194 //static int do_tint=0; 195 196 #define DEBUG_Q40INT 197 /*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */ 198 199 static int mext_disabled=0; /* ext irq disabled by master chip? */ 200 static int aliased_irq=0; /* how many times inside handler ?*/ 201 202 203 /* got interrupt, dispatch to ISA or keyboard/timer IRQs */ 204 static void q40_irq_handler(unsigned int irq, struct pt_regs *fp) 205 { 206 unsigned mir, mer; 207 int i; 208 209 //repeat: 210 mir = master_inb(IIRQ_REG); 211 #ifdef CONFIG_BLK_DEV_FD 212 if ((mir & Q40_IRQ_EXT_MASK) && 213 (master_inb(EIRQ_REG) & Q40_IRQ6_MASK)) { 214 floppy_hardint(); 215 return; 216 } 217 #endif 218 switch (irq) { 219 case 4: 220 case 6: 221 __m68k_handle_int(Q40_IRQ_SAMPLE, fp); 222 return; 223 } 224 if (mir & Q40_IRQ_FRAME_MASK) { 225 __m68k_handle_int(Q40_IRQ_FRAME, fp); 226 master_outb(-1, FRAME_CLEAR_REG); 227 } 228 if ((mir & Q40_IRQ_SER_MASK) || (mir & Q40_IRQ_EXT_MASK)) { 229 mer = master_inb(EIRQ_REG); 230 for (i = 0; eirqs[i].mask; i++) { 231 if (mer & eirqs[i].mask) { 232 irq = eirqs[i].irq; 233 /* 234 * There is a little mess wrt which IRQ really caused this irq request. The 235 * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they 236 * are read - which is long after the request came in. In theory IRQs should 237 * not just go away but they occasionally do 238 */ 239 if (irq > 4 && irq <= 15 && mext_disabled) { 240 /*aliased_irq++;*/ 241 goto iirq; 242 } 243 if (q40_state[irq] & IRQ_INPROGRESS) { 244 /* some handlers do local_irq_enable() for irq latency reasons, */ 245 /* however reentering an active irq handler is not permitted */ 246 #ifdef IP_USE_DISABLE 247 /* in theory this is the better way to do it because it still */ 248 /* lets through eg the serial irqs, unfortunately it crashes */ 249 disable_irq(irq); 250 disabled = 1; 251 #else 252 /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n", 253 irq, disabled ? "already" : "not yet"); */ 254 fp->sr = (((fp->sr) & (~0x700))+0x200); 255 disabled = 1; 256 #endif 257 goto iirq; 258 } 259 q40_state[irq] |= IRQ_INPROGRESS; 260 __m68k_handle_int(irq, fp); 261 q40_state[irq] &= ~IRQ_INPROGRESS; 262 263 /* naively enable everything, if that fails than */ 264 /* this function will be reentered immediately thus */ 265 /* getting another chance to disable the IRQ */ 266 267 if (disabled) { 268 #ifdef IP_USE_DISABLE 269 if (irq > 4) { 270 disabled = 0; 271 enable_irq(irq); 272 } 273 #else 274 disabled = 0; 275 /*printk("reenabling irq %d\n", irq); */ 276 #endif 277 } 278 // used to do 'goto repeat;' here, this delayed bh processing too long 279 return; 280 } 281 } 282 if (mer && ccleirq > 0 && !aliased_irq) { 283 printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer); 284 ccleirq--; 285 } 286 } 287 iirq: 288 mir = master_inb(IIRQ_REG); 289 /* should test whether keyboard irq is really enabled, doing it in defhand */ 290 if (mir & Q40_IRQ_KEYB_MASK) 291 __m68k_handle_int(Q40_IRQ_KEYBOARD, fp); 292 293 return; 294 } 295 296 void q40_enable_irq(unsigned int irq) 297 { 298 if (irq >= 5 && irq <= 15) { 299 mext_disabled--; 300 if (mext_disabled > 0) 301 printk("q40_enable_irq : nested disable/enable\n"); 302 if (mext_disabled == 0) 303 master_outb(1, EXT_ENABLE_REG); 304 } 305 } 306 307 308 void q40_disable_irq(unsigned int irq) 309 { 310 /* disable ISA iqs : only do something if the driver has been 311 * verified to be Q40 "compatible" - right now IDE, NE2K 312 * Any driver should not attempt to sleep across disable_irq !! 313 */ 314 315 if (irq >= 5 && irq <= 15) { 316 master_outb(0, EXT_ENABLE_REG); 317 mext_disabled++; 318 if (mext_disabled > 1) 319 printk("disable_irq nesting count %d\n",mext_disabled); 320 } 321 } 322 323 unsigned long q40_probe_irq_on(void) 324 { 325 printk("irq probing not working - reconfigure the driver to avoid this\n"); 326 return -1; 327 } 328 int q40_probe_irq_off(unsigned long irqs) 329 { 330 return -1; 331 } 332