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/config.h>
  13 #include <linux/types.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel_stat.h>
  16 #include <linux/signal.h>
  17 #include <linux/sched.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/irq.h>
  20
  21 #include <asm/mipsregs.h>
  22 #include <asm/addrspace.h>
  23
  24 #include <asm/sgi/ioc.h>
  25 #include <asm/sgi/hpc3.h>
  26 #include <asm/sgi/ip22.h>
  27
  28 /* #define DEBUG_SGINT */
  29
  30 /* So far nothing hangs here */
  31 #undef USE_LIO3_IRQ
  32
  33 struct sgint_regs *sgint;
  34
  35 static char lc0msk_to_irqnr[256];
  36 static char lc1msk_to_irqnr[256];
  37 static char lc2msk_to_irqnr[256];
  38 static char lc3msk_to_irqnr[256];
  39
  40 extern int ip22_eisa_init(void);
  41
  42 static void enable_local0_irq(unsigned int irq)
  43 {
  44         unsigned long flags;
  45
  46         local_irq_save(flags);
  47         /* don't allow mappable interrupt to be enabled from setup_irq,
  48          * we have our own way to do so */
  49         if (irq != SGI_MAP_0_IRQ)
  50                 sgint->imask0 |= (1 << (irq - SGINT_LOCAL0));
  51         local_irq_restore(flags);
  52 }
  53
  54 static unsigned int startup_local0_irq(unsigned int irq)
  55 {
  56         enable_local0_irq(irq);
  57         return 0;               /* Never anything pending  */
  58 }
  59
  60 static void disable_local0_irq(unsigned int irq)
  61 {
  62         unsigned long flags;
  63
  64         local_irq_save(flags);
  65         sgint->imask0 &= ~(1 << (irq - SGINT_LOCAL0));
  66         local_irq_restore(flags);
  67 }
  68
  69 #define shutdown_local0_irq     disable_local0_irq
  70 #define mask_and_ack_local0_irq disable_local0_irq
  71
  72 static void end_local0_irq (unsigned int irq)
  73 {
  74         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  75                 enable_local0_irq(irq);
  76 }
  77
  78 static struct hw_interrupt_type ip22_local0_irq_type = {
  79         .typename       = "IP22 local 0",
  80         .startup        = startup_local0_irq,
  81         .shutdown       = shutdown_local0_irq,
  82         .enable         = enable_local0_irq,
  83         .disable        = disable_local0_irq,
  84         .ack            = mask_and_ack_local0_irq,
  85         .end            = end_local0_irq,
  86 };
  87
  88 static void enable_local1_irq(unsigned int irq)
  89 {
  90         unsigned long flags;
  91
  92         local_irq_save(flags);
  93         /* don't allow mappable interrupt to be enabled from setup_irq,
  94          * we have our own way to do so */
  95         if (irq != SGI_MAP_1_IRQ)
  96                 sgint->imask1 |= (1 << (irq - SGINT_LOCAL1));
  97         local_irq_restore(flags);
  98 }
  99
 100 static unsigned int startup_local1_irq(unsigned int irq)
 101 {
 102         enable_local1_irq(irq);
 103         return 0;               /* Never anything pending  */
 104 }
 105
 106 void disable_local1_irq(unsigned int irq)
 107 {
 108         unsigned long flags;
 109
 110         local_irq_save(flags);
 111         sgint->imask1 &= ~(1 << (irq - SGINT_LOCAL1));
 112         local_irq_restore(flags);
 113 }
 114
 115 #define shutdown_local1_irq     disable_local1_irq
 116 #define mask_and_ack_local1_irq disable_local1_irq
 117
 118 static void end_local1_irq (unsigned int irq)
 119 {
 120         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 121                 enable_local1_irq(irq);
 122 }
 123
 124 static struct hw_interrupt_type ip22_local1_irq_type = {
 125         .typename       = "IP22 local 1",
 126         .startup        = startup_local1_irq,
 127         .shutdown       = shutdown_local1_irq,
 128         .enable         = enable_local1_irq,
 129         .disable        = disable_local1_irq,
 130         .ack            = mask_and_ack_local1_irq,
 131         .end            = end_local1_irq,
 132 };
 133
 134 static void enable_local2_irq(unsigned int irq)
 135 {
 136         unsigned long flags;
 137
 138         local_irq_save(flags);
 139         sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
 140         sgint->cmeimask0 |= (1 << (irq - SGINT_LOCAL2));
 141         local_irq_restore(flags);
 142 }
 143
 144 static unsigned int startup_local2_irq(unsigned int irq)
 145 {
 146         enable_local2_irq(irq);
 147         return 0;               /* Never anything pending  */
 148 }
 149
 150 void disable_local2_irq(unsigned int irq)
 151 {
 152         unsigned long flags;
 153
 154         local_irq_save(flags);
 155         sgint->cmeimask0 &= ~(1 << (irq - SGINT_LOCAL2));
 156         if (!sgint->cmeimask0)
 157                 sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
 158         local_irq_restore(flags);
 159 }
 160
 161 #define shutdown_local2_irq disable_local2_irq
 162 #define mask_and_ack_local2_irq disable_local2_irq
 163
 164 static void end_local2_irq (unsigned int irq)
 165 {
 166         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 167                 enable_local2_irq(irq);
 168 }
 169
 170 static struct hw_interrupt_type ip22_local2_irq_type = {
 171         .typename       = "IP22 local 2",
 172         .startup        = startup_local2_irq,
 173         .shutdown       = shutdown_local2_irq,
 174         .enable         = enable_local2_irq,
 175         .disable        = disable_local2_irq,
 176         .ack            = mask_and_ack_local2_irq,
 177         .end            = end_local2_irq,
 178 };
 179
 180 static void enable_local3_irq(unsigned int irq)
 181 {
 182         unsigned long flags;
 183
 184         local_irq_save(flags);
 185         sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 186         sgint->cmeimask1 |= (1 << (irq - SGINT_LOCAL3));
 187         local_irq_restore(flags);
 188 }
 189
 190 static unsigned int startup_local3_irq(unsigned int irq)
 191 {
 192         enable_local3_irq(irq);
 193         return 0;               /* Never anything pending  */
 194 }
 195
 196 void disable_local3_irq(unsigned int irq)
 197 {
 198         unsigned long flags;
 199
 200         local_irq_save(flags);
 201         sgint->cmeimask1 &= ~(1 << (irq - SGINT_LOCAL3));
 202         if (!sgint->cmeimask1)
 203                 sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 204         local_irq_restore(flags);
 205 }
 206
 207 #define shutdown_local3_irq disable_local3_irq
 208 #define mask_and_ack_local3_irq disable_local3_irq
 209
 210 static void end_local3_irq (unsigned int irq)
 211 {
 212         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 213                 enable_local3_irq(irq);
 214 }
 215
 216 static struct hw_interrupt_type ip22_local3_irq_type = {
 217         .typename       = "IP22 local 3",
 218         .startup        = startup_local3_irq,
 219         .shutdown       = shutdown_local3_irq,
 220         .enable         = enable_local3_irq,
 221         .disable        = disable_local3_irq,
 222         .ack            = mask_and_ack_local3_irq,
 223         .end            = end_local3_irq,
 224 };
 225
 226 static void indy_local0_irqdispatch(struct pt_regs *regs)
 227 {
 228         u8 mask = sgint->istat0 & sgint->imask0;
 229         u8 mask2;
 230         int irq;
 231
 232         if (mask & SGINT_ISTAT0_LIO2) {
 233                 mask2 = sgint->vmeistat & sgint->cmeimask0;
 234                 irq = lc2msk_to_irqnr[mask2];
 235         } else
 236                 irq = lc0msk_to_irqnr[mask];
 237
 238         /* if irq == 0, then the interrupt has already been cleared */
 239         if (irq)
 240                 do_IRQ(irq, regs);
 241         return;
 242 }
 243
 244 static void indy_local1_irqdispatch(struct pt_regs *regs)
 245 {
 246         u8 mask = sgint->istat1 & sgint->imask1;
 247         u8 mask2;
 248         int irq;
 249
 250         if (mask & SGINT_ISTAT1_LIO3) {
 251                 mask2 = sgint->vmeistat & sgint->cmeimask1;
 252                 irq = lc3msk_to_irqnr[mask2];
 253         } else
 254                 irq = lc1msk_to_irqnr[mask];
 255
 256         /* if irq == 0, then the interrupt has already been cleared */
 257         if (irq)
 258                 do_IRQ(irq, regs);
 259         return;
 260 }
 261
 262 extern void ip22_be_interrupt(int irq, struct pt_regs *regs);
 263
 264 static void indy_buserror_irq(struct pt_regs *regs)
 265 {
 266         int irq = SGI_BUSERR_IRQ;
 267
 268         irq_enter();
 269         kstat_this_cpu.irqs[irq]++;
 270         ip22_be_interrupt(irq, regs);
 271         irq_exit();
 272 }
 273
 274 static struct irqaction local0_cascade = {
 275         .handler        = no_action,
 276         .flags          = SA_INTERRUPT,
 277         .name           = "local0 cascade",
 278 };
 279
 280 static struct irqaction local1_cascade = {
 281         .handler        = no_action,
 282         .flags          = SA_INTERRUPT,
 283         .name           = "local1 cascade",
 284 };
 285
 286 static struct irqaction buserr = {
 287         .handler        = no_action,
 288         .flags          = SA_INTERRUPT,
 289         .name           = "Bus Error",
 290 };
 291
 292 static struct irqaction map0_cascade = {
 293         .handler        = no_action,
 294         .flags          = SA_INTERRUPT,
 295         .name           = "mapable0 cascade",
 296 };
 297
 298 #ifdef USE_LIO3_IRQ
 299 static struct irqaction map1_cascade = {
 300         .handler        = no_action,
 301         .flags          = SA_INTERRUPT,
 302         .name           = "mapable1 cascade",
 303 };
 304 #define SGI_INTERRUPTS  SGINT_END
 305 #else
 306 #define SGI_INTERRUPTS  SGINT_LOCAL3
 307 #endif
 308
 309 extern void indy_r4k_timer_interrupt(struct pt_regs *regs);
 310 extern void indy_8254timer_irq(struct pt_regs *regs);
 311
 312 /*
 313  * IRQs on the INDY look basically (barring software IRQs which we don't use
 314  * at all) like:
 315  *
 316  *      MIPS IRQ        Source
 317  *      --------        ------
 318  *             0        Software (ignored)
 319  *             1        Software (ignored)
 320  *             2        Local IRQ level zero
 321  *             3        Local IRQ level one
 322  *             4        8254 Timer zero
 323  *             5        8254 Timer one
 324  *             6        Bus Error
 325  *             7        R4k timer (what we use)
 326  *
 327  * We handle the IRQ according to _our_ priority which is:
 328  *
 329  * Highest ----     R4k Timer
 330  *                  Local IRQ zero
 331  *                  Local IRQ one
 332  *                  Bus Error
 333  *                  8254 Timer zero
 334  * Lowest  ----     8254 Timer one
 335  *
 336  * then we just return, if multiple IRQs are pending then we will just take
 337  * another exception, big deal.
 338  */
 339
 340 asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
 341 {
 342         unsigned int pending = read_c0_cause();
 343
 344         /*
 345          * First we check for r4k counter/timer IRQ.
 346          */
 347         if (pending & CAUSEF_IP7)
 348                 indy_r4k_timer_interrupt(regs);
 349         else if (pending & CAUSEF_IP2)
 350                 indy_local0_irqdispatch(regs);
 351         else if (pending & CAUSEF_IP3)
 352                 indy_local1_irqdispatch(regs);
 353         else if (pending & CAUSEF_IP6)
 354                 indy_buserror_irq(regs);
 355         else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
 356                 indy_8254timer_irq(regs);
 357 }
 358
 359 extern void mips_cpu_irq_init(unsigned int irq_base);
 360
 361 void __init arch_init_irq(void)
 362 {
 363         int i;
 364
 365         /* Init local mask --> irq tables. */
 366         for (i = 0; i < 256; i++) {
 367                 if (i & 0x80) {
 368                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
 369                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
 370                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
 371                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
 372                 } else if (i & 0x40) {
 373                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
 374                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
 375                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
 376                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
 377                 } else if (i & 0x20) {
 378                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
 379                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
 380                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
 381                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
 382                 } else if (i & 0x10) {
 383                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
 384                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
 385                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
 386                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
 387                 } else if (i & 0x08) {
 388                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
 389                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
 390                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
 391                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
 392                 } else if (i & 0x04) {
 393                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
 394                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
 395                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
 396                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
 397                 } else if (i & 0x02) {
 398                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
 399                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
 400                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
 401                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
 402                 } else if (i & 0x01) {
 403                         lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
 404                         lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
 405                         lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
 406                         lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
 407                 } else {
 408                         lc0msk_to_irqnr[i] = 0;
 409                         lc1msk_to_irqnr[i] = 0;
 410                         lc2msk_to_irqnr[i] = 0;
 411                         lc3msk_to_irqnr[i] = 0;
 412                 }
 413         }
 414
 415         /* Mask out all interrupts. */
 416         sgint->imask0 = 0;
 417         sgint->imask1 = 0;
 418         sgint->cmeimask0 = 0;
 419         sgint->cmeimask1 = 0;
 420
 421         /* init CPU irqs */
 422         mips_cpu_irq_init(SGINT_CPU);
 423
 424         for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
 425                 hw_irq_controller *handler;
 426
 427                 if (i < SGINT_LOCAL1)
 428                         handler         = &ip22_local0_irq_type;
 429                 else if (i < SGINT_LOCAL2)
 430                         handler         = &ip22_local1_irq_type;
 431                 else if (i < SGINT_LOCAL3)
 432                         handler         = &ip22_local2_irq_type;
 433                 else
 434                         handler         = &ip22_local3_irq_type;
 435
 436                 irq_desc[i].status      = IRQ_DISABLED;
 437                 irq_desc[i].action      = 0;
 438                 irq_desc[i].depth       = 1;
 439                 irq_desc[i].handler     = handler;
 440         }
 441
 442         /* vector handler. this register the IRQ as non-sharable */
 443         setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
 444         setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
 445         setup_irq(SGI_BUSERR_IRQ, &buserr);
 446
 447         /* cascade in cascade. i love Indy ;-) */
 448         setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
 449 #ifdef USE_LIO3_IRQ
 450         setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
 451 #endif
 452
 453 #ifdef CONFIG_EISA
 454         if (ip22_is_fullhouse())        /* Only Indigo-2 has EISA stuff */
 455                 ip22_eisa_init ();
 456 #endif
 457 }