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 irq_chip 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 irq_chip 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 irq_chip 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 irq_chip 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(void)
 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);
 240 }
 241
 242 static void indy_local1_irqdispatch(void)
 243 {
 244         u8 mask = sgint->istat1 & sgint->imask1;
 245         u8 mask2;
 246         int irq;
 247
 248         if (mask & SGINT_ISTAT1_LIO3) {
 249                 mask2 = sgint->vmeistat & sgint->cmeimask1;
 250                 irq = lc3msk_to_irqnr[mask2];
 251         } else
 252                 irq = lc1msk_to_irqnr[mask];
 253
 254         /* if irq == 0, then the interrupt has already been cleared */
 255         if (irq)
 256                 do_IRQ(irq);
 257 }
 258
 259 extern void ip22_be_interrupt(int irq);
 260
 261 static void indy_buserror_irq(void)
 262 {
 263         int irq = SGI_BUSERR_IRQ;
 264
 265         irq_enter();
 266         kstat_this_cpu.irqs[irq]++;
 267         ip22_be_interrupt(irq);
 268         irq_exit();
 269 }
 270
 271 static struct irqaction local0_cascade = {
 272         .handler        = no_action,
 273         .flags          = IRQF_DISABLED,
 274         .name           = "local0 cascade",
 275 };
 276
 277 static struct irqaction local1_cascade = {
 278         .handler        = no_action,
 279         .flags          = IRQF_DISABLED,
 280         .name           = "local1 cascade",
 281 };
 282
 283 static struct irqaction buserr = {
 284         .handler        = no_action,
 285         .flags          = IRQF_DISABLED,
 286         .name           = "Bus Error",
 287 };
 288
 289 static struct irqaction map0_cascade = {
 290         .handler        = no_action,
 291         .flags          = IRQF_DISABLED,
 292         .name           = "mapable0 cascade",
 293 };
 294
 295 #ifdef USE_LIO3_IRQ
 296 static struct irqaction map1_cascade = {
 297         .handler        = no_action,
 298         .flags          = IRQF_DISABLED,
 299         .name           = "mapable1 cascade",
 300 };
 301 #define SGI_INTERRUPTS  SGINT_END
 302 #else
 303 #define SGI_INTERRUPTS  SGINT_LOCAL3
 304 #endif
 305
 306 extern void indy_r4k_timer_interrupt(void);
 307 extern void indy_8254timer_irq(void);
 308
 309 /*
 310  * IRQs on the INDY look basically (barring software IRQs which we don't use
 311  * at all) like:
 312  *
 313  *      MIPS IRQ        Source
 314  *      --------        ------
 315  *             0        Software (ignored)
 316  *             1        Software (ignored)
 317  *             2        Local IRQ level zero
 318  *             3        Local IRQ level one
 319  *             4        8254 Timer zero
 320  *             5        8254 Timer one
 321  *             6        Bus Error
 322  *             7        R4k timer (what we use)
 323  *
 324  * We handle the IRQ according to _our_ priority which is:
 325  *
 326  * Highest ----     R4k Timer
 327  *                  Local IRQ zero
 328  *                  Local IRQ one
 329  *                  Bus Error
 330  *                  8254 Timer zero
 331  * Lowest  ----     8254 Timer one
 332  *
 333  * then we just return, if multiple IRQs are pending then we will just take
 334  * another exception, big deal.
 335  */
 336
 337 asmlinkage void plat_irq_dispatch(void)
 338 {
 339         unsigned int pending = read_c0_cause();
 340
 341         /*
 342          * First we check for r4k counter/timer IRQ.
 343          */
 344         if (pending & CAUSEF_IP7)
 345                 indy_r4k_timer_interrupt();
 346         else if (pending & CAUSEF_IP2)
 347                 indy_local0_irqdispatch();
 348         else if (pending & CAUSEF_IP3)
 349                 indy_local1_irqdispatch();
 350         else if (pending & CAUSEF_IP6)
 351                 indy_buserror_irq();
 352         else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
 353                 indy_8254timer_irq();
 354 }
 355
 356 extern void mips_cpu_irq_init(unsigned int irq_base);
 357
 358 void __init arch_init_irq(void)
 359 {
 360         int i;
 361
 362         /* Init local mask --> irq tables. */
 363         for (i = 0; i < 256; i++) {
 364                 if (i & 0x80) {
 365                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
 366                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
 367                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
 368                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
 369                 } else if (i & 0x40) {
 370                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
 371                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
 372                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
 373                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
 374                 } else if (i & 0x20) {
 375                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
 376                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
 377                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
 378                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
 379                 } else if (i & 0x10) {
 380                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
 381                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
 382                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
 383                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
 384                 } else if (i & 0x08) {
 385                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
 386                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
 387                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
 388                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
 389                 } else if (i & 0x04) {
 390                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
 391                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
 392                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
 393                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
 394                 } else if (i & 0x02) {
 395                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
 396                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
 397                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
 398                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
 399                 } else if (i & 0x01) {
 400                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
 401                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
 402                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
 403                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
 404                 } else {
 405                         lc0msk_to_irqnr[i] = 0;
 406                         lc1msk_to_irqnr[i] = 0;
 407                         lc2msk_to_irqnr[i] = 0;
 408                         lc3msk_to_irqnr[i] = 0;
 409                 }
 410         }
 411
 412         /* Mask out all interrupts. */
 413         sgint->imask0 = 0;
 414         sgint->imask1 = 0;
 415         sgint->cmeimask0 = 0;
 416         sgint->cmeimask1 = 0;
 417
 418         /* init CPU irqs */
 419         mips_cpu_irq_init(SGINT_CPU);
 420
 421         for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
 422                 struct irq_chip *handler;
 423
 424                 if (i < SGINT_LOCAL1)
 425                         handler         = &ip22_local0_irq_type;
 426                 else if (i < SGINT_LOCAL2)
 427                         handler         = &ip22_local1_irq_type;
 428                 else if (i < SGINT_LOCAL3)
 429                         handler         = &ip22_local2_irq_type;
 430                 else
 431                         handler         = &ip22_local3_irq_type;
 432
 433                 irq_desc[i].status      = IRQ_DISABLED;
 434                 irq_desc[i].action      = 0;
 435                 irq_desc[i].depth       = 1;
 436                 irq_desc[i].chip        = handler;
 437         }
 438
 439         /* vector handler. this register the IRQ as non-sharable */
 440         setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
 441         setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
 442         setup_irq(SGI_BUSERR_IRQ, &buserr);
 443
 444         /* cascade in cascade. i love Indy ;-) */
 445         setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
 446 #ifdef USE_LIO3_IRQ
 447         setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
 448 #endif
 449
 450 #ifdef CONFIG_EISA
 451         if (ip22_is_fullhouse())        /* Only Indigo-2 has EISA stuff */
 452                 ip22_eisa_init ();
 453 #endif
 454 }