linux/arch/mips/sgi-ip22/ip22-int.c
<<
>>
Prefs
   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#include <asm/irq_cpu.h>
  23#include <asm/sgi/ioc.h>
  24#include <asm/sgi/hpc3.h>
  25#include <asm/sgi/ip22.h>
  26#include <asm/time.h>
  27
  28/* #define DEBUG_SGINT */
  29
  30/* So far nothing hangs here */
  31#undef USE_LIO3_IRQ
  32
  33struct sgint_regs *sgint;
  34
  35static char lc0msk_to_irqnr[256];
  36static char lc1msk_to_irqnr[256];
  37static char lc2msk_to_irqnr[256];
  38static char lc3msk_to_irqnr[256];
  39
  40extern int ip22_eisa_init(void);
  41
  42static void enable_local0_irq(unsigned int irq)
  43{
  44        /* don't allow mappable interrupt to be enabled from setup_irq,
  45         * we have our own way to do so */
  46        if (irq != SGI_MAP_0_IRQ)
  47                sgint->imask0 |= (1 << (irq - SGINT_LOCAL0));
  48}
  49
  50static void disable_local0_irq(unsigned int irq)
  51{
  52        sgint->imask0 &= ~(1 << (irq - SGINT_LOCAL0));
  53}
  54
  55static struct irq_chip ip22_local0_irq_type = {
  56        .name           = "IP22 local 0",
  57        .ack            = disable_local0_irq,
  58        .mask           = disable_local0_irq,
  59        .mask_ack       = disable_local0_irq,
  60        .unmask         = enable_local0_irq,
  61};
  62
  63static void enable_local1_irq(unsigned int irq)
  64{
  65        /* don't allow mappable interrupt to be enabled from setup_irq,
  66         * we have our own way to do so */
  67        if (irq != SGI_MAP_1_IRQ)
  68                sgint->imask1 |= (1 << (irq - SGINT_LOCAL1));
  69}
  70
  71void disable_local1_irq(unsigned int irq)
  72{
  73        sgint->imask1 &= ~(1 << (irq - SGINT_LOCAL1));
  74}
  75
  76static struct irq_chip ip22_local1_irq_type = {
  77        .name           = "IP22 local 1",
  78        .ack            = disable_local1_irq,
  79        .mask           = disable_local1_irq,
  80        .mask_ack       = disable_local1_irq,
  81        .unmask         = enable_local1_irq,
  82};
  83
  84static void enable_local2_irq(unsigned int irq)
  85{
  86        sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
  87        sgint->cmeimask0 |= (1 << (irq - SGINT_LOCAL2));
  88}
  89
  90void disable_local2_irq(unsigned int irq)
  91{
  92        sgint->cmeimask0 &= ~(1 << (irq - SGINT_LOCAL2));
  93        if (!sgint->cmeimask0)
  94                sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
  95}
  96
  97static struct irq_chip ip22_local2_irq_type = {
  98        .name           = "IP22 local 2",
  99        .ack            = disable_local2_irq,
 100        .mask           = disable_local2_irq,
 101        .mask_ack       = disable_local2_irq,
 102        .unmask         = enable_local2_irq,
 103};
 104
 105static void enable_local3_irq(unsigned int irq)
 106{
 107        sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 108        sgint->cmeimask1 |= (1 << (irq - SGINT_LOCAL3));
 109}
 110
 111void disable_local3_irq(unsigned int irq)
 112{
 113        sgint->cmeimask1 &= ~(1 << (irq - SGINT_LOCAL3));
 114        if (!sgint->cmeimask1)
 115                sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
 116}
 117
 118static struct irq_chip ip22_local3_irq_type = {
 119        .name           = "IP22 local 3",
 120        .ack            = disable_local3_irq,
 121        .mask           = disable_local3_irq,
 122        .mask_ack       = disable_local3_irq,
 123        .unmask         = enable_local3_irq,
 124};
 125
 126static void indy_local0_irqdispatch(void)
 127{
 128        u8 mask = sgint->istat0 & sgint->imask0;
 129        u8 mask2;
 130        int irq;
 131
 132        if (mask & SGINT_ISTAT0_LIO2) {
 133                mask2 = sgint->vmeistat & sgint->cmeimask0;
 134                irq = lc2msk_to_irqnr[mask2];
 135        } else
 136                irq = lc0msk_to_irqnr[mask];
 137
 138        /* if irq == 0, then the interrupt has already been cleared */
 139        if (irq)
 140                do_IRQ(irq);
 141}
 142
 143static void indy_local1_irqdispatch(void)
 144{
 145        u8 mask = sgint->istat1 & sgint->imask1;
 146        u8 mask2;
 147        int irq;
 148
 149        if (mask & SGINT_ISTAT1_LIO3) {
 150                mask2 = sgint->vmeistat & sgint->cmeimask1;
 151                irq = lc3msk_to_irqnr[mask2];
 152        } else
 153                irq = lc1msk_to_irqnr[mask];
 154
 155        /* if irq == 0, then the interrupt has already been cleared */
 156        if (irq)
 157                do_IRQ(irq);
 158}
 159
 160extern void ip22_be_interrupt(int irq);
 161
 162static void indy_buserror_irq(void)
 163{
 164        int irq = SGI_BUSERR_IRQ;
 165
 166        irq_enter();
 167        kstat_this_cpu.irqs[irq]++;
 168        ip22_be_interrupt(irq);
 169        irq_exit();
 170}
 171
 172static struct irqaction local0_cascade = {
 173        .handler        = no_action,
 174        .flags          = IRQF_DISABLED,
 175        .name           = "local0 cascade",
 176};
 177
 178static struct irqaction local1_cascade = {
 179        .handler        = no_action,
 180        .flags          = IRQF_DISABLED,
 181        .name           = "local1 cascade",
 182};
 183
 184static struct irqaction buserr = {
 185        .handler        = no_action,
 186        .flags          = IRQF_DISABLED,
 187        .name           = "Bus Error",
 188};
 189
 190static struct irqaction map0_cascade = {
 191        .handler        = no_action,
 192        .flags          = IRQF_DISABLED,
 193        .name           = "mapable0 cascade",
 194};
 195
 196#ifdef USE_LIO3_IRQ
 197static struct irqaction map1_cascade = {
 198        .handler        = no_action,
 199        .flags          = IRQF_DISABLED,
 200        .name           = "mapable1 cascade",
 201};
 202#define SGI_INTERRUPTS  SGINT_END
 203#else
 204#define SGI_INTERRUPTS  SGINT_LOCAL3
 205#endif
 206
 207extern void indy_8254timer_irq(void);
 208
 209/*
 210 * IRQs on the INDY look basically (barring software IRQs which we don't use
 211 * at all) like:
 212 *
 213 *      MIPS IRQ        Source
 214 *      --------        ------
 215 *             0        Software (ignored)
 216 *             1        Software (ignored)
 217 *             2        Local IRQ level zero
 218 *             3        Local IRQ level one
 219 *             4        8254 Timer zero
 220 *             5        8254 Timer one
 221 *             6        Bus Error
 222 *             7        R4k timer (what we use)
 223 *
 224 * We handle the IRQ according to _our_ priority which is:
 225 *
 226 * Highest ----     R4k Timer
 227 *                  Local IRQ zero
 228 *                  Local IRQ one
 229 *                  Bus Error
 230 *                  8254 Timer zero
 231 * Lowest  ----     8254 Timer one
 232 *
 233 * then we just return, if multiple IRQs are pending then we will just take
 234 * another exception, big deal.
 235 */
 236
 237asmlinkage void plat_irq_dispatch(void)
 238{
 239        unsigned int pending = read_c0_status() & read_c0_cause();
 240
 241        /*
 242         * First we check for r4k counter/timer IRQ.
 243         */
 244        if (pending & CAUSEF_IP7)
 245                do_IRQ(SGI_TIMER_IRQ);
 246        else if (pending & CAUSEF_IP2)
 247                indy_local0_irqdispatch();
 248        else if (pending & CAUSEF_IP3)
 249                indy_local1_irqdispatch();
 250        else if (pending & CAUSEF_IP6)
 251                indy_buserror_irq();
 252        else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
 253                indy_8254timer_irq();
 254}
 255
 256void __init arch_init_irq(void)
 257{
 258        int i;
 259
 260        /* Init local mask --> irq tables. */
 261        for (i = 0; i < 256; i++) {
 262                if (i & 0x80) {
 263                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
 264                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
 265                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
 266                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
 267                } else if (i & 0x40) {
 268                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
 269                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
 270                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
 271                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
 272                } else if (i & 0x20) {
 273                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
 274                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
 275                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
 276                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
 277                } else if (i & 0x10) {
 278                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
 279                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
 280                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
 281                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
 282                } else if (i & 0x08) {
 283                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
 284                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
 285                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
 286                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
 287                } else if (i & 0x04) {
 288                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
 289                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
 290                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
 291                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
 292                } else if (i & 0x02) {
 293                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
 294                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
 295                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
 296                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
 297                } else if (i & 0x01) {
 298                        lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
 299                        lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
 300                        lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
 301                        lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
 302                } else {
 303                        lc0msk_to_irqnr[i] = 0;
 304                        lc1msk_to_irqnr[i] = 0;
 305                        lc2msk_to_irqnr[i] = 0;
 306                        lc3msk_to_irqnr[i] = 0;
 307                }
 308        }
 309
 310        /* Mask out all interrupts. */
 311        sgint->imask0 = 0;
 312        sgint->imask1 = 0;
 313        sgint->cmeimask0 = 0;
 314        sgint->cmeimask1 = 0;
 315
 316        /* init CPU irqs */
 317        mips_cpu_irq_init();
 318
 319        for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
 320                struct irq_chip *handler;
 321
 322                if (i < SGINT_LOCAL1)
 323                        handler         = &ip22_local0_irq_type;
 324                else if (i < SGINT_LOCAL2)
 325                        handler         = &ip22_local1_irq_type;
 326                else if (i < SGINT_LOCAL3)
 327                        handler         = &ip22_local2_irq_type;
 328                else
 329                        handler         = &ip22_local3_irq_type;
 330
 331                set_irq_chip_and_handler(i, handler, handle_level_irq);
 332        }
 333
 334        /* vector handler. this register the IRQ as non-sharable */
 335        setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
 336        setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
 337        setup_irq(SGI_BUSERR_IRQ, &buserr);
 338
 339        /* cascade in cascade. i love Indy ;-) */
 340        setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
 341#ifdef USE_LIO3_IRQ
 342        setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
 343#endif
 344
 345#ifdef CONFIG_EISA
 346        if (ip22_is_fullhouse())        /* Only Indigo-2 has EISA stuff */
 347                ip22_eisa_init();
 348#endif
 349}
 350