arch/mips/sgi-ip22/ip22-int.c

   1 /*
   2  * ip22-int.c: Routines for generic manipulation of the INT[23] ASIC
   3  *             found on INDY and Indigo2 workstations.
   4  *
   5  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   6  * Copyright (C) 1997, 1998 Ralf Baechle (ralf@gnu.org)
   7  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
   8  *                    - Indigo2 changes
   9  *                    - Interrupt handling fixes
  10  * Copyright (C) 2001, 2003 Ladislav Michl (ladis@linux-mips.org)
  11  */
  12 #include <linux/types.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel_stat.h>
  15 #include <linux/signal.h>
  16 #include <linux/sched.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/irq.h>
  19
  20 #include <asm/mipsregs.h>
  21 #include <asm/addrspace.h>
  22
  23 #include <asm/sgi/ioc.h>
  24 #include <asm/sgi/hpc3.h>
  25 #include <asm/sgi/ip22.h>
  26
  27 /* #define DEBUG_SGINT */
  28
  29 /* So far nothing hangs here */
  30 #undef USE_LIO3_IRQ
  31
  32 struct sgint_regs *sgint;
  33
  34 static char lc0msk_to_irqnr[256];
  35 static char lc1msk_to_irqnr[256];
  36 static char lc2msk_to_irqnr[256];
  37 static char lc3msk_to_irqnr[256];
  38
  39 extern int ip22_eisa_init(void);
  40
  41 static void enable_local0_irq(unsigned int irq)
  42 {
  43         unsigned long flags;
  44
  45         local_irq_save(flags);
  46         /* don't allow mappable interrupt to be enabled from setup_irq,
  47          * we have our own way to do so */
  48         if (irq != SGI_MAP_0_IRQ)
  49                 sgint->imask0 |= (1 << (irq - SGINT_LOCAL0));
  50         local_irq_restore(flags);
  51 }
  52
  53 static unsigned int startup_local0_irq(unsigned int irq)
  54 {
  55         enable_local0_irq(irq);
  56         return 0;               /* Never anything pending  */
  57 }
  58
  59 static void disable_local0_irq(unsigned int irq)
  60 {
  61         unsigned long flags;
  62
  63         local_irq_save(flags);
  64         sgint->imask0 &= ~(1 << (irq - SGINT_LOCAL0));
  65         local_irq_restore(flags);
  66 }
  67
  68 #define shutdown_local0_irq     disable_local0_irq
  69 #define mask_and_ack_local0_irq disable_local0_irq
  70
  71 static void end_local0_irq (unsigned int irq)
  72 {
  73         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  74                 enable_local0_irq(irq);
  75 }
  76
  77 static struct hw_interrupt_type ip22_local0_irq_type = {
  78         .typename       = "IP22 local 0",
  79         .startup        = startup_local0_irq,
  80         .shutdown       = shutdown_local0_irq,
  81         .enable         = enable_local0_irq,
  82         .disable        = disable_local0_irq,
  83         .ack            = mask_and_ack_local0_irq,
  84         .end            = end_local0_irq,
  85 };
  86
  87 static void enable_local1_irq(unsigned int irq)
  88 {
  89         unsigned long flags;
  90
  91         local_irq_save(flags);
  92         /* don't allow mappable interrupt to be enabled from setup_irq,
  93          * we have our own way to do so */
  94         if (irq != SGI_MAP_1_IRQ)
  95                 sgint->imask1 |= (1 << (irq - SGINT_LOCAL1));
  96         local_irq_restore(flags);
  97 }
  98
  99 static unsigned int startup_local1_irq(unsigned int irq)
 100 {
 101         enable_local1_irq(irq);
 102         return 0;               /* Never anything pending  */
 103 }
 104
 105 void disable_local1_irq(unsigned int irq)
 106 {
 107         unsigned long flags;
 108
 109         local_irq_save(flags);
 110         sgint->imask1 &= ~(1 << (irq - SGINT_LOCAL1));
 111         local_irq_restore(flags);
 112 }
 113
 114 #define shutdown_local1_irq     disable_local1_irq
 115 #define mask_and_ack_local1_irq disable_local1_irq
 116
 117 static void end_local1_irq (unsigned int irq)
 118 {
 119         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 120                 enable_local1_irq(irq);
 121 }
 122
 123 static struct hw_interrupt_type ip22_local1_irq_type = {
 124         .typename       = "IP22 local 1",
 125         .startup        = startup_local1_irq,
 126         .shutdown       = shutdown_local1_irq,
 127         .enable         = enable_local1_irq,
 128         .disable        = disable_local1_irq,
 129         .ack            = mask_and_ack_local1_irq,
 130         .end            = end_local1_irq,
 131 };
 132
 133 static void enable_local2_irq(unsigned int irq)
 134 {
 135         unsigned long flags;
 136
 137         local_irq_save(flags);
 138         sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
 139         sgint->cmeimask0 |= (1 << (irq - SGINT_LOCAL2));
 140         local_irq_restore(flags);
 141 }
 142
 143 static unsigned int startup_local2_irq(unsigned int irq)
 144 {
 145         enable_local2_irq(irq);
 146         return 0;               /* Never anything pending  */
 147 }
 148
 149 void disable_local2_irq(unsigned int irq)
 150 {
 151         unsigned long flags;
 152
 153         local_irq_save(flags);
 154         sgint->cmeimask0 &= ~(1 << (irq - SGINT_LOCAL2));
 155         if (!sgint->cmeimask0)
 156                 sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
 157         local_irq_restore(flags);
 158 }
 159
 160 #define shutdown_local2_irq disable_local2_irq
 161 #define mask_and_ack_local2_irq disable_local2_irq
 162
 163 static void end_local2_irq (unsigned int irq)
 164 {
 165         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 166                 enable_local2_irq(irq);
 167 }
 168
 169 static struct hw_interrupt_type ip22_local2_irq_type = {
 170         .typename       = "IP22 local 2",
 171         .startup        = startup_local2_irq,
 172         .shutdown       = shutdown_local2_irq,
 173         .enable         = enable_local2_irq,
 174         .disable        = disable_local2_irq,
 175         .ack            = mask_and_ack_local2_irq,
 176         .end            = end_local2_irq,
 177 };
 178
 179 static void enable_local3_irq(unsigned int irq)
 180 {
 181         unsigned long flags;
 182
 183         local_irq_save(flags);
 184         sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 185         sgint->cmeimask1 |= (1 << (irq - SGINT_LOCAL3));
 186         local_irq_restore(flags);
 187 }
 188
 189 static unsigned int startup_local3_irq(unsigned int irq)
 190 {
 191         enable_local3_irq(irq);
 192         return 0;               /* Never anything pending  */
 193 }
 194
 195 void disable_local3_irq(unsigned int irq)
 196 {
 197         unsigned long flags;
 198
 199         local_irq_save(flags);
 200         sgint->cmeimask1 &= ~(1 << (irq - SGINT_LOCAL3));
 201         if (!sgint->cmeimask1)
 202                 sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 203         local_irq_restore(flags);
 204 }
 205
 206 #define shutdown_local3_irq disable_local3_irq
 207 #define mask_and_ack_local3_irq disable_local3_irq
 208
 209 static void end_local3_irq (unsigned int irq)
 210 {
 211         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 212                 enable_local3_irq(irq);
 213 }
 214
 215 static struct hw_interrupt_type ip22_local3_irq_type = {
 216         .typename       = "IP22 local 3",
 217         .startup        = startup_local3_irq,
 218         .shutdown       = shutdown_local3_irq,
 219         .enable         = enable_local3_irq,
 220         .disable        = disable_local3_irq,
 221         .ack            = mask_and_ack_local3_irq,
 222         .end            = end_local3_irq,
 223 };
 224
 225 static void indy_local0_irqdispatch(struct pt_regs *regs)
 226 {
 227         u8 mask = sgint->istat0 & sgint->imask0;
 228         u8 mask2;
 229         int irq;
 230
 231         if (mask & SGINT_ISTAT0_LIO2) {
 232                 mask2 = sgint->vmeistat & sgint->cmeimask0;
 233                 irq = lc2msk_to_irqnr[mask2];
 234         } else
 235                 irq = lc0msk_to_irqnr[mask];
 236
 237         /* if irq == 0, then the interrupt has already been cleared */
 238         if (irq)
 239                 do_IRQ(irq, regs);
 240         return;
 241 }
 242
 243 static void indy_local1_irqdispatch(struct pt_regs *regs)
 244 {
 245         u8 mask = sgint->istat1 & sgint->imask1;
 246         u8 mask2;
 247         int irq;
 248
 249         if (mask & SGINT_ISTAT1_LIO3) {
 250                 mask2 = sgint->vmeistat & sgint->cmeimask1;
 251                 irq = lc3msk_to_irqnr[mask2];
 252         } else
 253                 irq = lc1msk_to_irqnr[mask];
 254
 255         /* if irq == 0, then the interrupt has already been cleared */
 256         if (irq)
 257                 do_IRQ(irq, regs);
 258         return;
 259 }
 260
 261 extern void ip22_be_interrupt(int irq, struct pt_regs *regs);
 262
 263 static void indy_buserror_irq(struct pt_regs *regs)
 264 {
 265         int irq = SGI_BUSERR_IRQ;
 266
 267         irq_enter();
 268         kstat_this_cpu.irqs[irq]++;
 269         ip22_be_interrupt(irq, regs);
 270         irq_exit();
 271 }
 272
 273 static struct irqaction local0_cascade = {
 274         .handler        = no_action,
 275         .flags          = SA_INTERRUPT,
 276         .name           = "local0 cascade",
 277 };
 278
 279 static struct irqaction local1_cascade = {
 280         .handler        = no_action,
 281         .flags          = SA_INTERRUPT,
 282         .name           = "local1 cascade",
 283 };
 284
 285 static struct irqaction buserr = {
 286         .handler        = no_action,
 287         .flags          = SA_INTERRUPT,
 288         .name           = "Bus Error",
 289 };
 290
 291 static struct irqaction map0_cascade = {
 292         .handler        = no_action,
 293         .flags          = SA_INTERRUPT,
 294         .name           = "mapable0 cascade",
 295 };
 296
 297 #ifdef USE_LIO3_IRQ
 298 static struct irqaction map1_cascade = {
 299         .handler        = no_action,
 300         .flags          = SA_INTERRUPT,
 301         .name           = "mapable1 cascade",
 302 };
 303 #define SGI_INTERRUPTS  SGINT_END
 304 #else
 305 #define SGI_INTERRUPTS  SGINT_LOCAL3
 306 #endif
 307
 308 extern void indy_r4k_timer_interrupt(struct pt_regs *regs);
 309 extern void indy_8254timer_irq(struct pt_regs *regs);
 310
 311 /*
 312  * IRQs on the INDY look basically (barring software IRQs which we don't use
 313  * at all) like:
 314  *
 315  *      MIPS IRQ        Source
 316  *      --------        ------
 317  *             0        Software (ignored)
 318  *             1        Software (ignored)
 319  *             2        Local IRQ level zero
 320  *             3        Local IRQ level one
 321  *             4        8254 Timer zero
 322  *             5        8254 Timer one
 323  *             6        Bus Error
 324  *             7        R4k timer (what we use)
 325  *
 326  * We handle the IRQ according to _our_ priority which is:
 327  *
 328  * Highest ----     R4k Timer
 329  *                  Local IRQ zero
 330  *                  Local IRQ one
 331  *                  Bus Error
 332  *                  8254 Timer zero
 333  * Lowest  ----     8254 Timer one
 334  *
 335  * then we just return, if multiple IRQs are pending then we will just take
 336  * another exception, big deal.
 337  */
 338
 339 asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
 340 {
 341         unsigned int pending = read_c0_cause();
 342
 343         /*
 344          * First we check for r4k counter/timer IRQ.
 345          */
 346         if (pending & CAUSEF_IP7)
 347                 indy_r4k_timer_interrupt(regs);
 348         else if (pending & CAUSEF_IP2)
 349                 indy_local0_irqdispatch(regs);
 350         else if (pending & CAUSEF_IP3)
 351                 indy_local1_irqdispatch(regs);
 352         else if (pending & CAUSEF_IP6)
 353                 indy_buserror_irq(regs);
 354         else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
 355                 indy_8254timer_irq(regs);
 356 }
 357
 358 extern void mips_cpu_irq_init(unsigned int irq_base);
 359
 360 void __init arch_init_irq(void)
 361 {
 362         int i;
 363
 364         /* Init local mask --> irq tables. */
 365         for (i = 0; i < 256; i++) {
 366                 if (i & 0x80) {
 367                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
 368                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
 369                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
 370                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
 371                 } else if (i & 0x40) {
 372                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
 373                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
 374                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
 375                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
 376                 } else if (i & 0x20) {
 377                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
 378                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
 379                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
 380                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
 381                 } else if (i & 0x10) {
 382                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
 383                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
 384                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
 385                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
 386                 } else if (i & 0x08) {
 387                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
 388                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
 389                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
 390                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
 391                 } else if (i & 0x04) {
 392                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
 393                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
 394                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
 395                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
 396                 } else if (i & 0x02) {
 397                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
 398                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
 399                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
 400                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
 401                 } else if (i & 0x01) {
 402                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
 403                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
 404                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
 405                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
 406                 } else {
 407                         lc0msk_to_irqnr[i] = 0;
 408                         lc1msk_to_irqnr[i] = 0;
 409                         lc2msk_to_irqnr[i] = 0;
 410                         lc3msk_to_irqnr[i] = 0;
 411                 }
 412         }
 413
 414         /* Mask out all interrupts. */
 415         sgint->imask0 = 0;
 416         sgint->imask1 = 0;
 417         sgint->cmeimask0 = 0;
 418         sgint->cmeimask1 = 0;
 419
 420         /* init CPU irqs */
 421         mips_cpu_irq_init(SGINT_CPU);
 422
 423         for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
 424                 hw_irq_controller *handler;
 425
 426                 if (i < SGINT_LOCAL1)
 427                         handler         = &ip22_local0_irq_type;
 428                 else if (i < SGINT_LOCAL2)
 429                         handler         = &ip22_local1_irq_type;
 430                 else if (i < SGINT_LOCAL3)
 431                         handler         = &ip22_local2_irq_type;
 432                 else
 433                         handler         = &ip22_local3_irq_type;
 434
 435                 irq_desc[i].status      = IRQ_DISABLED;
 436                 irq_desc[i].action      = 0;
 437                 irq_desc[i].depth       = 1;
 438                 irq_desc[i].chip        = handler;
 439         }
 440
 441         /* vector handler. this register the IRQ as non-sharable */
 442         setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
 443         setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
 444         setup_irq(SGI_BUSERR_IRQ, &buserr);
 445
 446         /* cascade in cascade. i love Indy ;-) */
 447         setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
 448 #ifdef USE_LIO3_IRQ
 449         setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
 450 #endif
 451
 452 #ifdef CONFIG_EISA
 453         if (ip22_is_fullhouse())        /* Only Indigo-2 has EISA stuff */
 454                 ip22_eisa_init ();
 455 #endif
 456 }