1 /* 2 * Macintosh interrupts 3 * 4 * General design: 5 * In contrary to the Amiga and Atari platforms, the Mac hardware seems to 6 * exclusively use the autovector interrupts (the 'generic level0-level7' 7 * interrupts with exception vectors 0x19-0x1f). The following interrupt levels 8 * are used: 9 * 1 - VIA1 10 * - slot 0: one second interrupt (CA2) 11 * - slot 1: VBlank (CA1) 12 * - slot 2: ADB data ready (SR full) 13 * - slot 3: ADB data (CB2) 14 * - slot 4: ADB clock (CB1) 15 * - slot 5: timer 2 16 * - slot 6: timer 1 17 * - slot 7: status of IRQ; signals 'any enabled int.' 18 * 19 * 2 - VIA2 or RBV 20 * - slot 0: SCSI DRQ (CA2) 21 * - slot 1: NUBUS IRQ (CA1) need to read port A to find which 22 * - slot 2: /EXP IRQ (only on IIci) 23 * - slot 3: SCSI IRQ (CB2) 24 * - slot 4: ASC IRQ (CB1) 25 * - slot 5: timer 2 (not on IIci) 26 * - slot 6: timer 1 (not on IIci) 27 * - slot 7: status of IRQ; signals 'any enabled int.' 28 * 29 * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes: 30 * 31 * 3 - unused (?) 32 * 33 * 4 - SCC 34 * 35 * 5 - unused (?) 36 * [serial errors or special conditions seem to raise level 6 37 * interrupts on some models (LC4xx?)] 38 * 39 * 6 - off switch (?) 40 * 41 * Machines with Quadra-like VIA hardware, except PSC and PMU machines, support 42 * an alternate interrupt mapping, as used by A/UX. It spreads ethernet and 43 * sound out to their own autovector IRQs and gives VIA1 a higher priority: 44 * 45 * 1 - unused (?) 46 * 47 * 3 - on-board SONIC 48 * 49 * 5 - Apple Sound Chip (ASC) 50 * 51 * 6 - VIA1 52 * 53 * For OSS Macintoshes (IIfx only), we apply an interrupt mapping similar to 54 * the Quadra (A/UX) mapping: 55 * 56 * 1 - ISM IOP (ADB) 57 * 58 * 2 - SCSI 59 * 60 * 3 - NuBus 61 * 62 * 4 - SCC IOP 63 * 64 * 6 - VIA1 65 * 66 * For PSC Macintoshes (660AV, 840AV): 67 * 68 * 3 - PSC level 3 69 * - slot 0: MACE 70 * 71 * 4 - PSC level 4 72 * - slot 1: SCC channel A interrupt 73 * - slot 2: SCC channel B interrupt 74 * - slot 3: MACE DMA 75 * 76 * 5 - PSC level 5 77 * 78 * 6 - PSC level 6 79 * 80 * Finally we have good 'ole level 7, the non-maskable interrupt: 81 * 82 * 7 - NMI (programmer's switch on the back of some Macs) 83 * Also RAM parity error on models which support it (IIc, IIfx?) 84 * 85 * The current interrupt logic looks something like this: 86 * 87 * - We install dispatchers for the autovector interrupts (1-7). These 88 * dispatchers are responsible for querying the hardware (the 89 * VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using 90 * this information a machspec interrupt number is generated by placing the 91 * index of the interrupt hardware into the low three bits and the original 92 * autovector interrupt number in the upper 5 bits. The handlers for the 93 * resulting machspec interrupt are then called. 94 * 95 * - Nubus is a special case because its interrupts are hidden behind two 96 * layers of hardware. Nubus interrupts come in as index 1 on VIA #2, 97 * which translates to IRQ number 17. In this spot we install _another_ 98 * dispatcher. This dispatcher finds the interrupting slot number (9-F) and 99 * then forms a new machspec interrupt number as above with the slot number 100 * minus 9 in the low three bits and the pseudo-level 7 in the upper five 101 * bits. The handlers for this new machspec interrupt number are then 102 * called. This puts Nubus interrupts into the range 56-62. 103 * 104 * - The Baboon interrupts (used on some PowerBooks) are an even more special 105 * case. They're hidden behind the Nubus slot $C interrupt thus adding a 106 * third layer of indirection. Why oh why did the Apple engineers do that? 107 * 108 */ 109 110 #include <linux/types.h> 111 #include <linux/kernel.h> 112 #include <linux/sched.h> 113 #include <linux/interrupt.h> 114 #include <linux/irq.h> 115 #include <linux/delay.h> 116 117 #include <asm/irq.h> 118 #include <asm/macintosh.h> 119 #include <asm/macints.h> 120 #include <asm/mac_via.h> 121 #include <asm/mac_psc.h> 122 #include <asm/mac_oss.h> 123 #include <asm/mac_iop.h> 124 #include <asm/mac_baboon.h> 125 #include <asm/hwtest.h> 126 #include <asm/irq_regs.h> 127 128 #define SHUTUP_SONIC 129 130 /* 131 * console_loglevel determines NMI handler function 132 */ 133 134 irqreturn_t mac_nmi_handler(int, void *); 135 irqreturn_t mac_debug_handler(int, void *); 136 137 /* #define DEBUG_MACINTS */ 138 139 static unsigned int mac_irq_startup(struct irq_data *); 140 static void mac_irq_shutdown(struct irq_data *); 141 142 static struct irq_chip mac_irq_chip = { 143 .name = "mac", 144 .irq_enable = mac_irq_enable, 145 .irq_disable = mac_irq_disable, 146 .irq_startup = mac_irq_startup, 147 .irq_shutdown = mac_irq_shutdown, 148 }; 149 150 void __init mac_init_IRQ(void) 151 { 152 #ifdef DEBUG_MACINTS 153 printk("mac_init_IRQ(): Setting things up...\n"); 154 #endif 155 m68k_setup_irq_controller(&mac_irq_chip, handle_simple_irq, IRQ_USER, 156 NUM_MAC_SOURCES - IRQ_USER); 157 /* Make sure the SONIC interrupt is cleared or things get ugly */ 158 #ifdef SHUTUP_SONIC 159 printk("Killing onboard sonic... "); 160 /* This address should hopefully be mapped already */ 161 if (hwreg_present((void*)(0x50f0a000))) { 162 *(long *)(0x50f0a014) = 0x7fffL; 163 *(long *)(0x50f0a010) = 0L; 164 } 165 printk("Done.\n"); 166 #endif /* SHUTUP_SONIC */ 167 168 /* 169 * Now register the handlers for the master IRQ handlers 170 * at levels 1-7. Most of the work is done elsewhere. 171 */ 172 173 if (oss_present) 174 oss_register_interrupts(); 175 else 176 via_register_interrupts(); 177 if (psc) 178 psc_register_interrupts(); 179 if (baboon_present) 180 baboon_register_interrupts(); 181 iop_register_interrupts(); 182 if (request_irq(IRQ_AUTO_7, mac_nmi_handler, 0, "NMI", 183 mac_nmi_handler)) 184 pr_err("Couldn't register NMI\n"); 185 #ifdef DEBUG_MACINTS 186 printk("mac_init_IRQ(): Done!\n"); 187 #endif 188 } 189 190 /* 191 * mac_irq_enable - enable an interrupt source 192 * mac_irq_disable - disable an interrupt source 193 * 194 * These routines are just dispatchers to the VIA/OSS/PSC routines. 195 */ 196 197 void mac_irq_enable(struct irq_data *data) 198 { 199 int irq = data->irq; 200 int irq_src = IRQ_SRC(irq); 201 202 switch(irq_src) { 203 case 1: 204 case 2: 205 case 7: 206 if (oss_present) 207 oss_irq_enable(irq); 208 else 209 via_irq_enable(irq); 210 break; 211 case 3: 212 case 4: 213 case 5: 214 case 6: 215 if (psc) 216 psc_irq_enable(irq); 217 else if (oss_present) 218 oss_irq_enable(irq); 219 break; 220 case 8: 221 if (baboon_present) 222 baboon_irq_enable(irq); 223 break; 224 } 225 } 226 227 void mac_irq_disable(struct irq_data *data) 228 { 229 int irq = data->irq; 230 int irq_src = IRQ_SRC(irq); 231 232 switch(irq_src) { 233 case 1: 234 case 2: 235 case 7: 236 if (oss_present) 237 oss_irq_disable(irq); 238 else 239 via_irq_disable(irq); 240 break; 241 case 3: 242 case 4: 243 case 5: 244 case 6: 245 if (psc) 246 psc_irq_disable(irq); 247 else if (oss_present) 248 oss_irq_disable(irq); 249 break; 250 case 8: 251 if (baboon_present) 252 baboon_irq_disable(irq); 253 break; 254 } 255 } 256 257 static unsigned int mac_irq_startup(struct irq_data *data) 258 { 259 int irq = data->irq; 260 261 if (IRQ_SRC(irq) == 7 && !oss_present) 262 via_nubus_irq_startup(irq); 263 else 264 mac_irq_enable(data); 265 266 return 0; 267 } 268 269 static void mac_irq_shutdown(struct irq_data *data) 270 { 271 int irq = data->irq; 272 273 if (IRQ_SRC(irq) == 7 && !oss_present) 274 via_nubus_irq_shutdown(irq); 275 else 276 mac_irq_disable(data); 277 } 278 279 static int num_debug[8]; 280 281 irqreturn_t mac_debug_handler(int irq, void *dev_id) 282 { 283 if (num_debug[irq] < 10) { 284 printk("DEBUG: Unexpected IRQ %d\n", irq); 285 num_debug[irq]++; 286 } 287 return IRQ_HANDLED; 288 } 289 290 static int in_nmi; 291 static volatile int nmi_hold; 292 293 irqreturn_t mac_nmi_handler(int irq, void *dev_id) 294 { 295 int i; 296 /* 297 * generate debug output on NMI switch if 'debug' kernel option given 298 * (only works with Penguin!) 299 */ 300 301 in_nmi++; 302 for (i=0; i<100; i++) 303 udelay(1000); 304 305 if (in_nmi == 1) { 306 nmi_hold = 1; 307 printk("... pausing, press NMI to resume ..."); 308 } else { 309 printk(" ok!\n"); 310 nmi_hold = 0; 311 } 312 313 barrier(); 314 315 while (nmi_hold == 1) 316 udelay(1000); 317 318 if (console_loglevel >= 8) { 319 #if 0 320 struct pt_regs *fp = get_irq_regs(); 321 show_state(); 322 printk("PC: %08lx\nSR: %04x SP: %p\n", fp->pc, fp->sr, fp); 323 printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n", 324 fp->d0, fp->d1, fp->d2, fp->d3); 325 printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n", 326 fp->d4, fp->d5, fp->a0, fp->a1); 327 328 if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page) 329 printk("Corrupted stack page\n"); 330 printk("Process %s (pid: %d, stackpage=%08lx)\n", 331 current->comm, current->pid, current->kernel_stack_page); 332 if (intr_count == 1) 333 dump_stack((struct frame *)fp); 334 #else 335 /* printk("NMI "); */ 336 #endif 337 } 338 in_nmi--; 339 return IRQ_HANDLED; 340 } 341