linux/arch/mips/dec/setup.c
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   1/*
   2 * System-specific setup, especially interrupts.
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1998 Harald Koerfgen
   9 * Copyright (C) 2000, 2001, 2002, 2003, 2005, 2020  Maciej W. Rozycki
  10 */
  11#include <linux/console.h>
  12#include <linux/export.h>
  13#include <linux/init.h>
  14#include <linux/interrupt.h>
  15#include <linux/ioport.h>
  16#include <linux/irq.h>
  17#include <linux/irqnr.h>
  18#include <linux/memblock.h>
  19#include <linux/param.h>
  20#include <linux/percpu-defs.h>
  21#include <linux/sched.h>
  22#include <linux/spinlock.h>
  23#include <linux/types.h>
  24#include <linux/pm.h>
  25
  26#include <asm/addrspace.h>
  27#include <asm/bootinfo.h>
  28#include <asm/cpu.h>
  29#include <asm/cpu-features.h>
  30#include <asm/cpu-type.h>
  31#include <asm/irq.h>
  32#include <asm/irq_cpu.h>
  33#include <asm/mipsregs.h>
  34#include <asm/page.h>
  35#include <asm/reboot.h>
  36#include <asm/sections.h>
  37#include <asm/time.h>
  38#include <asm/traps.h>
  39#include <asm/wbflush.h>
  40
  41#include <asm/dec/interrupts.h>
  42#include <asm/dec/ioasic.h>
  43#include <asm/dec/ioasic_addrs.h>
  44#include <asm/dec/ioasic_ints.h>
  45#include <asm/dec/kn01.h>
  46#include <asm/dec/kn02.h>
  47#include <asm/dec/kn02ba.h>
  48#include <asm/dec/kn02ca.h>
  49#include <asm/dec/kn03.h>
  50#include <asm/dec/kn230.h>
  51#include <asm/dec/system.h>
  52
  53
  54extern void dec_machine_restart(char *command);
  55extern void dec_machine_halt(void);
  56extern void dec_machine_power_off(void);
  57extern irqreturn_t dec_intr_halt(int irq, void *dev_id);
  58
  59unsigned long dec_kn_slot_base, dec_kn_slot_size;
  60
  61EXPORT_SYMBOL(dec_kn_slot_base);
  62EXPORT_SYMBOL(dec_kn_slot_size);
  63
  64int dec_tc_bus;
  65
  66DEFINE_SPINLOCK(ioasic_ssr_lock);
  67EXPORT_SYMBOL(ioasic_ssr_lock);
  68
  69volatile u32 *ioasic_base;
  70
  71EXPORT_SYMBOL(ioasic_base);
  72
  73/*
  74 * IRQ routing and priority tables.  Priorites are set as follows:
  75 *
  76 *              KN01    KN230   KN02    KN02-BA KN02-CA KN03
  77 *
  78 * MEMORY       CPU     CPU     CPU     ASIC    CPU     CPU
  79 * RTC          CPU     CPU     CPU     ASIC    CPU     CPU
  80 * DMA          -       -       -       ASIC    ASIC    ASIC
  81 * SERIAL0      CPU     CPU     CSR     ASIC    ASIC    ASIC
  82 * SERIAL1      -       -       -       ASIC    -       ASIC
  83 * SCSI         CPU     CPU     CSR     ASIC    ASIC    ASIC
  84 * ETHERNET     CPU     *       CSR     ASIC    ASIC    ASIC
  85 * other        -       -       -       ASIC    -       -
  86 * TC2          -       -       CSR     CPU     ASIC    ASIC
  87 * TC1          -       -       CSR     CPU     ASIC    ASIC
  88 * TC0          -       -       CSR     CPU     ASIC    ASIC
  89 * other        -       CPU     -       CPU     ASIC    ASIC
  90 * other        -       -       -       -       CPU     CPU
  91 *
  92 * * -- shared with SCSI
  93 */
  94
  95int dec_interrupt[DEC_NR_INTS] = {
  96        [0 ... DEC_NR_INTS - 1] = -1
  97};
  98
  99EXPORT_SYMBOL(dec_interrupt);
 100
 101int_ptr cpu_mask_nr_tbl[DEC_MAX_CPU_INTS][2] = {
 102        { { .i = ~0 }, { .p = dec_intr_unimplemented } },
 103};
 104int_ptr asic_mask_nr_tbl[DEC_MAX_ASIC_INTS][2] = {
 105        { { .i = ~0 }, { .p = asic_intr_unimplemented } },
 106};
 107int cpu_fpu_mask = DEC_CPU_IRQ_MASK(DEC_CPU_INR_FPU);
 108int *fpu_kstat_irq;
 109
 110static irq_handler_t busirq_handler;
 111static unsigned int busirq_flags = IRQF_NO_THREAD;
 112
 113/*
 114 * Bus error (DBE/IBE exceptions and bus interrupts) handling setup.
 115 */
 116static void __init dec_be_init(void)
 117{
 118        switch (mips_machtype) {
 119        case MACH_DS23100:      /* DS2100/DS3100 Pmin/Pmax */
 120                board_be_handler = dec_kn01_be_handler;
 121                busirq_handler = dec_kn01_be_interrupt;
 122                busirq_flags |= IRQF_SHARED;
 123                dec_kn01_be_init();
 124                break;
 125        case MACH_DS5000_1XX:   /* DS5000/1xx 3min */
 126        case MACH_DS5000_XX:    /* DS5000/xx Maxine */
 127                board_be_handler = dec_kn02xa_be_handler;
 128                busirq_handler = dec_kn02xa_be_interrupt;
 129                dec_kn02xa_be_init();
 130                break;
 131        case MACH_DS5000_200:   /* DS5000/200 3max */
 132        case MACH_DS5000_2X0:   /* DS5000/240 3max+ */
 133        case MACH_DS5900:       /* DS5900 bigmax */
 134                board_be_handler = dec_ecc_be_handler;
 135                busirq_handler = dec_ecc_be_interrupt;
 136                dec_ecc_be_init();
 137                break;
 138        }
 139}
 140
 141void __init plat_mem_setup(void)
 142{
 143        board_be_init = dec_be_init;
 144
 145        wbflush_setup();
 146
 147        _machine_restart = dec_machine_restart;
 148        _machine_halt = dec_machine_halt;
 149        pm_power_off = dec_machine_power_off;
 150
 151        ioport_resource.start = ~0UL;
 152        ioport_resource.end = 0UL;
 153
 154        /* Stay away from the firmware working memory area for now. */
 155        memblock_reserve(PHYS_OFFSET, __pa_symbol(&_text) - PHYS_OFFSET);
 156}
 157
 158/*
 159 * Machine-specific initialisation for KN01, aka DS2100 (aka Pmin)
 160 * or DS3100 (aka Pmax).
 161 */
 162static int kn01_interrupt[DEC_NR_INTS] __initdata = {
 163        [DEC_IRQ_CASCADE]       = -1,
 164        [DEC_IRQ_AB_RECV]       = -1,
 165        [DEC_IRQ_AB_XMIT]       = -1,
 166        [DEC_IRQ_DZ11]          = DEC_CPU_IRQ_NR(KN01_CPU_INR_DZ11),
 167        [DEC_IRQ_ASC]           = -1,
 168        [DEC_IRQ_FLOPPY]        = -1,
 169        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 170        [DEC_IRQ_HALT]          = -1,
 171        [DEC_IRQ_ISDN]          = -1,
 172        [DEC_IRQ_LANCE]         = DEC_CPU_IRQ_NR(KN01_CPU_INR_LANCE),
 173        [DEC_IRQ_BUS]           = DEC_CPU_IRQ_NR(KN01_CPU_INR_BUS),
 174        [DEC_IRQ_PSU]           = -1,
 175        [DEC_IRQ_RTC]           = DEC_CPU_IRQ_NR(KN01_CPU_INR_RTC),
 176        [DEC_IRQ_SCC0]          = -1,
 177        [DEC_IRQ_SCC1]          = -1,
 178        [DEC_IRQ_SII]           = DEC_CPU_IRQ_NR(KN01_CPU_INR_SII),
 179        [DEC_IRQ_TC0]           = -1,
 180        [DEC_IRQ_TC1]           = -1,
 181        [DEC_IRQ_TC2]           = -1,
 182        [DEC_IRQ_TIMER]         = -1,
 183        [DEC_IRQ_VIDEO]         = DEC_CPU_IRQ_NR(KN01_CPU_INR_VIDEO),
 184        [DEC_IRQ_ASC_MERR]      = -1,
 185        [DEC_IRQ_ASC_ERR]       = -1,
 186        [DEC_IRQ_ASC_DMA]       = -1,
 187        [DEC_IRQ_FLOPPY_ERR]    = -1,
 188        [DEC_IRQ_ISDN_ERR]      = -1,
 189        [DEC_IRQ_ISDN_RXDMA]    = -1,
 190        [DEC_IRQ_ISDN_TXDMA]    = -1,
 191        [DEC_IRQ_LANCE_MERR]    = -1,
 192        [DEC_IRQ_SCC0A_RXERR]   = -1,
 193        [DEC_IRQ_SCC0A_RXDMA]   = -1,
 194        [DEC_IRQ_SCC0A_TXERR]   = -1,
 195        [DEC_IRQ_SCC0A_TXDMA]   = -1,
 196        [DEC_IRQ_AB_RXERR]      = -1,
 197        [DEC_IRQ_AB_RXDMA]      = -1,
 198        [DEC_IRQ_AB_TXERR]      = -1,
 199        [DEC_IRQ_AB_TXDMA]      = -1,
 200        [DEC_IRQ_SCC1A_RXERR]   = -1,
 201        [DEC_IRQ_SCC1A_RXDMA]   = -1,
 202        [DEC_IRQ_SCC1A_TXERR]   = -1,
 203        [DEC_IRQ_SCC1A_TXDMA]   = -1,
 204};
 205
 206static int_ptr kn01_cpu_mask_nr_tbl[][2] __initdata = {
 207        { { .i = DEC_CPU_IRQ_MASK(KN01_CPU_INR_BUS) },
 208                { .i = DEC_CPU_IRQ_NR(KN01_CPU_INR_BUS) } },
 209        { { .i = DEC_CPU_IRQ_MASK(KN01_CPU_INR_RTC) },
 210                { .i = DEC_CPU_IRQ_NR(KN01_CPU_INR_RTC) } },
 211        { { .i = DEC_CPU_IRQ_MASK(KN01_CPU_INR_DZ11) },
 212                { .i = DEC_CPU_IRQ_NR(KN01_CPU_INR_DZ11) } },
 213        { { .i = DEC_CPU_IRQ_MASK(KN01_CPU_INR_SII) },
 214                { .i = DEC_CPU_IRQ_NR(KN01_CPU_INR_SII) } },
 215        { { .i = DEC_CPU_IRQ_MASK(KN01_CPU_INR_LANCE) },
 216                { .i = DEC_CPU_IRQ_NR(KN01_CPU_INR_LANCE) } },
 217        { { .i = DEC_CPU_IRQ_ALL },
 218                { .p = cpu_all_int } },
 219};
 220
 221static void __init dec_init_kn01(void)
 222{
 223        /* IRQ routing. */
 224        memcpy(&dec_interrupt, &kn01_interrupt,
 225                sizeof(kn01_interrupt));
 226
 227        /* CPU IRQ priorities. */
 228        memcpy(&cpu_mask_nr_tbl, &kn01_cpu_mask_nr_tbl,
 229                sizeof(kn01_cpu_mask_nr_tbl));
 230
 231        mips_cpu_irq_init();
 232
 233}                               /* dec_init_kn01 */
 234
 235
 236/*
 237 * Machine-specific initialisation for KN230, aka DS5100, aka MIPSmate.
 238 */
 239static int kn230_interrupt[DEC_NR_INTS] __initdata = {
 240        [DEC_IRQ_CASCADE]       = -1,
 241        [DEC_IRQ_AB_RECV]       = -1,
 242        [DEC_IRQ_AB_XMIT]       = -1,
 243        [DEC_IRQ_DZ11]          = DEC_CPU_IRQ_NR(KN230_CPU_INR_DZ11),
 244        [DEC_IRQ_ASC]           = -1,
 245        [DEC_IRQ_FLOPPY]        = -1,
 246        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 247        [DEC_IRQ_HALT]          = DEC_CPU_IRQ_NR(KN230_CPU_INR_HALT),
 248        [DEC_IRQ_ISDN]          = -1,
 249        [DEC_IRQ_LANCE]         = DEC_CPU_IRQ_NR(KN230_CPU_INR_LANCE),
 250        [DEC_IRQ_BUS]           = DEC_CPU_IRQ_NR(KN230_CPU_INR_BUS),
 251        [DEC_IRQ_PSU]           = -1,
 252        [DEC_IRQ_RTC]           = DEC_CPU_IRQ_NR(KN230_CPU_INR_RTC),
 253        [DEC_IRQ_SCC0]          = -1,
 254        [DEC_IRQ_SCC1]          = -1,
 255        [DEC_IRQ_SII]           = DEC_CPU_IRQ_NR(KN230_CPU_INR_SII),
 256        [DEC_IRQ_TC0]           = -1,
 257        [DEC_IRQ_TC1]           = -1,
 258        [DEC_IRQ_TC2]           = -1,
 259        [DEC_IRQ_TIMER]         = -1,
 260        [DEC_IRQ_VIDEO]         = -1,
 261        [DEC_IRQ_ASC_MERR]      = -1,
 262        [DEC_IRQ_ASC_ERR]       = -1,
 263        [DEC_IRQ_ASC_DMA]       = -1,
 264        [DEC_IRQ_FLOPPY_ERR]    = -1,
 265        [DEC_IRQ_ISDN_ERR]      = -1,
 266        [DEC_IRQ_ISDN_RXDMA]    = -1,
 267        [DEC_IRQ_ISDN_TXDMA]    = -1,
 268        [DEC_IRQ_LANCE_MERR]    = -1,
 269        [DEC_IRQ_SCC0A_RXERR]   = -1,
 270        [DEC_IRQ_SCC0A_RXDMA]   = -1,
 271        [DEC_IRQ_SCC0A_TXERR]   = -1,
 272        [DEC_IRQ_SCC0A_TXDMA]   = -1,
 273        [DEC_IRQ_AB_RXERR]      = -1,
 274        [DEC_IRQ_AB_RXDMA]      = -1,
 275        [DEC_IRQ_AB_TXERR]      = -1,
 276        [DEC_IRQ_AB_TXDMA]      = -1,
 277        [DEC_IRQ_SCC1A_RXERR]   = -1,
 278        [DEC_IRQ_SCC1A_RXDMA]   = -1,
 279        [DEC_IRQ_SCC1A_TXERR]   = -1,
 280        [DEC_IRQ_SCC1A_TXDMA]   = -1,
 281};
 282
 283static int_ptr kn230_cpu_mask_nr_tbl[][2] __initdata = {
 284        { { .i = DEC_CPU_IRQ_MASK(KN230_CPU_INR_BUS) },
 285                { .i = DEC_CPU_IRQ_NR(KN230_CPU_INR_BUS) } },
 286        { { .i = DEC_CPU_IRQ_MASK(KN230_CPU_INR_RTC) },
 287                { .i = DEC_CPU_IRQ_NR(KN230_CPU_INR_RTC) } },
 288        { { .i = DEC_CPU_IRQ_MASK(KN230_CPU_INR_DZ11) },
 289                { .i = DEC_CPU_IRQ_NR(KN230_CPU_INR_DZ11) } },
 290        { { .i = DEC_CPU_IRQ_MASK(KN230_CPU_INR_SII) },
 291                { .i = DEC_CPU_IRQ_NR(KN230_CPU_INR_SII) } },
 292        { { .i = DEC_CPU_IRQ_ALL },
 293                { .p = cpu_all_int } },
 294};
 295
 296static void __init dec_init_kn230(void)
 297{
 298        /* IRQ routing. */
 299        memcpy(&dec_interrupt, &kn230_interrupt,
 300                sizeof(kn230_interrupt));
 301
 302        /* CPU IRQ priorities. */
 303        memcpy(&cpu_mask_nr_tbl, &kn230_cpu_mask_nr_tbl,
 304                sizeof(kn230_cpu_mask_nr_tbl));
 305
 306        mips_cpu_irq_init();
 307
 308}                               /* dec_init_kn230 */
 309
 310
 311/*
 312 * Machine-specific initialisation for KN02, aka DS5000/200, aka 3max.
 313 */
 314static int kn02_interrupt[DEC_NR_INTS] __initdata = {
 315        [DEC_IRQ_CASCADE]       = DEC_CPU_IRQ_NR(KN02_CPU_INR_CASCADE),
 316        [DEC_IRQ_AB_RECV]       = -1,
 317        [DEC_IRQ_AB_XMIT]       = -1,
 318        [DEC_IRQ_DZ11]          = KN02_IRQ_NR(KN02_CSR_INR_DZ11),
 319        [DEC_IRQ_ASC]           = KN02_IRQ_NR(KN02_CSR_INR_ASC),
 320        [DEC_IRQ_FLOPPY]        = -1,
 321        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 322        [DEC_IRQ_HALT]          = -1,
 323        [DEC_IRQ_ISDN]          = -1,
 324        [DEC_IRQ_LANCE]         = KN02_IRQ_NR(KN02_CSR_INR_LANCE),
 325        [DEC_IRQ_BUS]           = DEC_CPU_IRQ_NR(KN02_CPU_INR_BUS),
 326        [DEC_IRQ_PSU]           = -1,
 327        [DEC_IRQ_RTC]           = DEC_CPU_IRQ_NR(KN02_CPU_INR_RTC),
 328        [DEC_IRQ_SCC0]          = -1,
 329        [DEC_IRQ_SCC1]          = -1,
 330        [DEC_IRQ_SII]           = -1,
 331        [DEC_IRQ_TC0]           = KN02_IRQ_NR(KN02_CSR_INR_TC0),
 332        [DEC_IRQ_TC1]           = KN02_IRQ_NR(KN02_CSR_INR_TC1),
 333        [DEC_IRQ_TC2]           = KN02_IRQ_NR(KN02_CSR_INR_TC2),
 334        [DEC_IRQ_TIMER]         = -1,
 335        [DEC_IRQ_VIDEO]         = -1,
 336        [DEC_IRQ_ASC_MERR]      = -1,
 337        [DEC_IRQ_ASC_ERR]       = -1,
 338        [DEC_IRQ_ASC_DMA]       = -1,
 339        [DEC_IRQ_FLOPPY_ERR]    = -1,
 340        [DEC_IRQ_ISDN_ERR]      = -1,
 341        [DEC_IRQ_ISDN_RXDMA]    = -1,
 342        [DEC_IRQ_ISDN_TXDMA]    = -1,
 343        [DEC_IRQ_LANCE_MERR]    = -1,
 344        [DEC_IRQ_SCC0A_RXERR]   = -1,
 345        [DEC_IRQ_SCC0A_RXDMA]   = -1,
 346        [DEC_IRQ_SCC0A_TXERR]   = -1,
 347        [DEC_IRQ_SCC0A_TXDMA]   = -1,
 348        [DEC_IRQ_AB_RXERR]      = -1,
 349        [DEC_IRQ_AB_RXDMA]      = -1,
 350        [DEC_IRQ_AB_TXERR]      = -1,
 351        [DEC_IRQ_AB_TXDMA]      = -1,
 352        [DEC_IRQ_SCC1A_RXERR]   = -1,
 353        [DEC_IRQ_SCC1A_RXDMA]   = -1,
 354        [DEC_IRQ_SCC1A_TXERR]   = -1,
 355        [DEC_IRQ_SCC1A_TXDMA]   = -1,
 356};
 357
 358static int_ptr kn02_cpu_mask_nr_tbl[][2] __initdata = {
 359        { { .i = DEC_CPU_IRQ_MASK(KN02_CPU_INR_BUS) },
 360                { .i = DEC_CPU_IRQ_NR(KN02_CPU_INR_BUS) } },
 361        { { .i = DEC_CPU_IRQ_MASK(KN02_CPU_INR_RTC) },
 362                { .i = DEC_CPU_IRQ_NR(KN02_CPU_INR_RTC) } },
 363        { { .i = DEC_CPU_IRQ_MASK(KN02_CPU_INR_CASCADE) },
 364                { .p = kn02_io_int } },
 365        { { .i = DEC_CPU_IRQ_ALL },
 366                { .p = cpu_all_int } },
 367};
 368
 369static int_ptr kn02_asic_mask_nr_tbl[][2] __initdata = {
 370        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_DZ11) },
 371                { .i = KN02_IRQ_NR(KN02_CSR_INR_DZ11) } },
 372        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_ASC) },
 373                { .i = KN02_IRQ_NR(KN02_CSR_INR_ASC) } },
 374        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_LANCE) },
 375                { .i = KN02_IRQ_NR(KN02_CSR_INR_LANCE) } },
 376        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_TC2) },
 377                { .i = KN02_IRQ_NR(KN02_CSR_INR_TC2) } },
 378        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_TC1) },
 379                { .i = KN02_IRQ_NR(KN02_CSR_INR_TC1) } },
 380        { { .i = KN02_IRQ_MASK(KN02_CSR_INR_TC0) },
 381                { .i = KN02_IRQ_NR(KN02_CSR_INR_TC0) } },
 382        { { .i = KN02_IRQ_ALL },
 383                { .p = kn02_all_int } },
 384};
 385
 386static void __init dec_init_kn02(void)
 387{
 388        /* IRQ routing. */
 389        memcpy(&dec_interrupt, &kn02_interrupt,
 390                sizeof(kn02_interrupt));
 391
 392        /* CPU IRQ priorities. */
 393        memcpy(&cpu_mask_nr_tbl, &kn02_cpu_mask_nr_tbl,
 394                sizeof(kn02_cpu_mask_nr_tbl));
 395
 396        /* KN02 CSR IRQ priorities. */
 397        memcpy(&asic_mask_nr_tbl, &kn02_asic_mask_nr_tbl,
 398                sizeof(kn02_asic_mask_nr_tbl));
 399
 400        mips_cpu_irq_init();
 401        init_kn02_irqs(KN02_IRQ_BASE);
 402
 403}                               /* dec_init_kn02 */
 404
 405
 406/*
 407 * Machine-specific initialisation for KN02-BA, aka DS5000/1xx
 408 * (xx = 20, 25, 33), aka 3min.  Also applies to KN04(-BA), aka
 409 * DS5000/150, aka 4min.
 410 */
 411static int kn02ba_interrupt[DEC_NR_INTS] __initdata = {
 412        [DEC_IRQ_CASCADE]       = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_CASCADE),
 413        [DEC_IRQ_AB_RECV]       = -1,
 414        [DEC_IRQ_AB_XMIT]       = -1,
 415        [DEC_IRQ_DZ11]          = -1,
 416        [DEC_IRQ_ASC]           = IO_IRQ_NR(KN02BA_IO_INR_ASC),
 417        [DEC_IRQ_FLOPPY]        = -1,
 418        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 419        [DEC_IRQ_HALT]          = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_HALT),
 420        [DEC_IRQ_ISDN]          = -1,
 421        [DEC_IRQ_LANCE]         = IO_IRQ_NR(KN02BA_IO_INR_LANCE),
 422        [DEC_IRQ_BUS]           = IO_IRQ_NR(KN02BA_IO_INR_BUS),
 423        [DEC_IRQ_PSU]           = IO_IRQ_NR(KN02BA_IO_INR_PSU),
 424        [DEC_IRQ_RTC]           = IO_IRQ_NR(KN02BA_IO_INR_RTC),
 425        [DEC_IRQ_SCC0]          = IO_IRQ_NR(KN02BA_IO_INR_SCC0),
 426        [DEC_IRQ_SCC1]          = IO_IRQ_NR(KN02BA_IO_INR_SCC1),
 427        [DEC_IRQ_SII]           = -1,
 428        [DEC_IRQ_TC0]           = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC0),
 429        [DEC_IRQ_TC1]           = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC1),
 430        [DEC_IRQ_TC2]           = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC2),
 431        [DEC_IRQ_TIMER]         = -1,
 432        [DEC_IRQ_VIDEO]         = -1,
 433        [DEC_IRQ_ASC_MERR]      = IO_IRQ_NR(IO_INR_ASC_MERR),
 434        [DEC_IRQ_ASC_ERR]       = IO_IRQ_NR(IO_INR_ASC_ERR),
 435        [DEC_IRQ_ASC_DMA]       = IO_IRQ_NR(IO_INR_ASC_DMA),
 436        [DEC_IRQ_FLOPPY_ERR]    = -1,
 437        [DEC_IRQ_ISDN_ERR]      = -1,
 438        [DEC_IRQ_ISDN_RXDMA]    = -1,
 439        [DEC_IRQ_ISDN_TXDMA]    = -1,
 440        [DEC_IRQ_LANCE_MERR]    = IO_IRQ_NR(IO_INR_LANCE_MERR),
 441        [DEC_IRQ_SCC0A_RXERR]   = IO_IRQ_NR(IO_INR_SCC0A_RXERR),
 442        [DEC_IRQ_SCC0A_RXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_RXDMA),
 443        [DEC_IRQ_SCC0A_TXERR]   = IO_IRQ_NR(IO_INR_SCC0A_TXERR),
 444        [DEC_IRQ_SCC0A_TXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_TXDMA),
 445        [DEC_IRQ_AB_RXERR]      = -1,
 446        [DEC_IRQ_AB_RXDMA]      = -1,
 447        [DEC_IRQ_AB_TXERR]      = -1,
 448        [DEC_IRQ_AB_TXDMA]      = -1,
 449        [DEC_IRQ_SCC1A_RXERR]   = IO_IRQ_NR(IO_INR_SCC1A_RXERR),
 450        [DEC_IRQ_SCC1A_RXDMA]   = IO_IRQ_NR(IO_INR_SCC1A_RXDMA),
 451        [DEC_IRQ_SCC1A_TXERR]   = IO_IRQ_NR(IO_INR_SCC1A_TXERR),
 452        [DEC_IRQ_SCC1A_TXDMA]   = IO_IRQ_NR(IO_INR_SCC1A_TXDMA),
 453};
 454
 455static int_ptr kn02ba_cpu_mask_nr_tbl[][2] __initdata = {
 456        { { .i = DEC_CPU_IRQ_MASK(KN02BA_CPU_INR_CASCADE) },
 457                { .p = kn02xa_io_int } },
 458        { { .i = DEC_CPU_IRQ_MASK(KN02BA_CPU_INR_TC2) },
 459                { .i = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC2) } },
 460        { { .i = DEC_CPU_IRQ_MASK(KN02BA_CPU_INR_TC1) },
 461                { .i = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC1) } },
 462        { { .i = DEC_CPU_IRQ_MASK(KN02BA_CPU_INR_TC0) },
 463                { .i = DEC_CPU_IRQ_NR(KN02BA_CPU_INR_TC0) } },
 464        { { .i = DEC_CPU_IRQ_ALL },
 465                { .p = cpu_all_int } },
 466};
 467
 468static int_ptr kn02ba_asic_mask_nr_tbl[][2] __initdata = {
 469        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_BUS) },
 470                { .i = IO_IRQ_NR(KN02BA_IO_INR_BUS) } },
 471        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_RTC) },
 472                { .i = IO_IRQ_NR(KN02BA_IO_INR_RTC) } },
 473        { { .i = IO_IRQ_DMA },
 474                { .p = asic_dma_int } },
 475        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_SCC0) },
 476                { .i = IO_IRQ_NR(KN02BA_IO_INR_SCC0) } },
 477        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_SCC1) },
 478                { .i = IO_IRQ_NR(KN02BA_IO_INR_SCC1) } },
 479        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_ASC) },
 480                { .i = IO_IRQ_NR(KN02BA_IO_INR_ASC) } },
 481        { { .i = IO_IRQ_MASK(KN02BA_IO_INR_LANCE) },
 482                { .i = IO_IRQ_NR(KN02BA_IO_INR_LANCE) } },
 483        { { .i = IO_IRQ_ALL },
 484                { .p = asic_all_int } },
 485};
 486
 487static void __init dec_init_kn02ba(void)
 488{
 489        /* IRQ routing. */
 490        memcpy(&dec_interrupt, &kn02ba_interrupt,
 491                sizeof(kn02ba_interrupt));
 492
 493        /* CPU IRQ priorities. */
 494        memcpy(&cpu_mask_nr_tbl, &kn02ba_cpu_mask_nr_tbl,
 495                sizeof(kn02ba_cpu_mask_nr_tbl));
 496
 497        /* I/O ASIC IRQ priorities. */
 498        memcpy(&asic_mask_nr_tbl, &kn02ba_asic_mask_nr_tbl,
 499                sizeof(kn02ba_asic_mask_nr_tbl));
 500
 501        mips_cpu_irq_init();
 502        init_ioasic_irqs(IO_IRQ_BASE);
 503
 504}                               /* dec_init_kn02ba */
 505
 506
 507/*
 508 * Machine-specific initialisation for KN02-CA, aka DS5000/xx,
 509 * (xx = 20, 25, 33), aka MAXine.  Also applies to KN04(-CA), aka
 510 * DS5000/50, aka 4MAXine.
 511 */
 512static int kn02ca_interrupt[DEC_NR_INTS] __initdata = {
 513        [DEC_IRQ_CASCADE]       = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_CASCADE),
 514        [DEC_IRQ_AB_RECV]       = IO_IRQ_NR(KN02CA_IO_INR_AB_RECV),
 515        [DEC_IRQ_AB_XMIT]       = IO_IRQ_NR(KN02CA_IO_INR_AB_XMIT),
 516        [DEC_IRQ_DZ11]          = -1,
 517        [DEC_IRQ_ASC]           = IO_IRQ_NR(KN02CA_IO_INR_ASC),
 518        [DEC_IRQ_FLOPPY]        = IO_IRQ_NR(KN02CA_IO_INR_FLOPPY),
 519        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 520        [DEC_IRQ_HALT]          = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_HALT),
 521        [DEC_IRQ_ISDN]          = IO_IRQ_NR(KN02CA_IO_INR_ISDN),
 522        [DEC_IRQ_LANCE]         = IO_IRQ_NR(KN02CA_IO_INR_LANCE),
 523        [DEC_IRQ_BUS]           = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_BUS),
 524        [DEC_IRQ_PSU]           = -1,
 525        [DEC_IRQ_RTC]           = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_RTC),
 526        [DEC_IRQ_SCC0]          = IO_IRQ_NR(KN02CA_IO_INR_SCC0),
 527        [DEC_IRQ_SCC1]          = -1,
 528        [DEC_IRQ_SII]           = -1,
 529        [DEC_IRQ_TC0]           = IO_IRQ_NR(KN02CA_IO_INR_TC0),
 530        [DEC_IRQ_TC1]           = IO_IRQ_NR(KN02CA_IO_INR_TC1),
 531        [DEC_IRQ_TC2]           = -1,
 532        [DEC_IRQ_TIMER]         = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_TIMER),
 533        [DEC_IRQ_VIDEO]         = IO_IRQ_NR(KN02CA_IO_INR_VIDEO),
 534        [DEC_IRQ_ASC_MERR]      = IO_IRQ_NR(IO_INR_ASC_MERR),
 535        [DEC_IRQ_ASC_ERR]       = IO_IRQ_NR(IO_INR_ASC_ERR),
 536        [DEC_IRQ_ASC_DMA]       = IO_IRQ_NR(IO_INR_ASC_DMA),
 537        [DEC_IRQ_FLOPPY_ERR]    = IO_IRQ_NR(IO_INR_FLOPPY_ERR),
 538        [DEC_IRQ_ISDN_ERR]      = IO_IRQ_NR(IO_INR_ISDN_ERR),
 539        [DEC_IRQ_ISDN_RXDMA]    = IO_IRQ_NR(IO_INR_ISDN_RXDMA),
 540        [DEC_IRQ_ISDN_TXDMA]    = IO_IRQ_NR(IO_INR_ISDN_TXDMA),
 541        [DEC_IRQ_LANCE_MERR]    = IO_IRQ_NR(IO_INR_LANCE_MERR),
 542        [DEC_IRQ_SCC0A_RXERR]   = IO_IRQ_NR(IO_INR_SCC0A_RXERR),
 543        [DEC_IRQ_SCC0A_RXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_RXDMA),
 544        [DEC_IRQ_SCC0A_TXERR]   = IO_IRQ_NR(IO_INR_SCC0A_TXERR),
 545        [DEC_IRQ_SCC0A_TXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_TXDMA),
 546        [DEC_IRQ_AB_RXERR]      = IO_IRQ_NR(IO_INR_AB_RXERR),
 547        [DEC_IRQ_AB_RXDMA]      = IO_IRQ_NR(IO_INR_AB_RXDMA),
 548        [DEC_IRQ_AB_TXERR]      = IO_IRQ_NR(IO_INR_AB_TXERR),
 549        [DEC_IRQ_AB_TXDMA]      = IO_IRQ_NR(IO_INR_AB_TXDMA),
 550        [DEC_IRQ_SCC1A_RXERR]   = -1,
 551        [DEC_IRQ_SCC1A_RXDMA]   = -1,
 552        [DEC_IRQ_SCC1A_TXERR]   = -1,
 553        [DEC_IRQ_SCC1A_TXDMA]   = -1,
 554};
 555
 556static int_ptr kn02ca_cpu_mask_nr_tbl[][2] __initdata = {
 557        { { .i = DEC_CPU_IRQ_MASK(KN02CA_CPU_INR_BUS) },
 558                { .i = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_BUS) } },
 559        { { .i = DEC_CPU_IRQ_MASK(KN02CA_CPU_INR_RTC) },
 560                { .i = DEC_CPU_IRQ_NR(KN02CA_CPU_INR_RTC) } },
 561        { { .i = DEC_CPU_IRQ_MASK(KN02CA_CPU_INR_CASCADE) },
 562                { .p = kn02xa_io_int } },
 563        { { .i = DEC_CPU_IRQ_ALL },
 564                { .p = cpu_all_int } },
 565};
 566
 567static int_ptr kn02ca_asic_mask_nr_tbl[][2] __initdata = {
 568        { { .i = IO_IRQ_DMA },
 569                { .p = asic_dma_int } },
 570        { { .i = IO_IRQ_MASK(KN02CA_IO_INR_SCC0) },
 571                { .i = IO_IRQ_NR(KN02CA_IO_INR_SCC0) } },
 572        { { .i = IO_IRQ_MASK(KN02CA_IO_INR_ASC) },
 573                { .i = IO_IRQ_NR(KN02CA_IO_INR_ASC) } },
 574        { { .i = IO_IRQ_MASK(KN02CA_IO_INR_LANCE) },
 575                { .i = IO_IRQ_NR(KN02CA_IO_INR_LANCE) } },
 576        { { .i = IO_IRQ_MASK(KN02CA_IO_INR_TC1) },
 577                { .i = IO_IRQ_NR(KN02CA_IO_INR_TC1) } },
 578        { { .i = IO_IRQ_MASK(KN02CA_IO_INR_TC0) },
 579                { .i = IO_IRQ_NR(KN02CA_IO_INR_TC0) } },
 580        { { .i = IO_IRQ_ALL },
 581                { .p = asic_all_int } },
 582};
 583
 584static void __init dec_init_kn02ca(void)
 585{
 586        /* IRQ routing. */
 587        memcpy(&dec_interrupt, &kn02ca_interrupt,
 588                sizeof(kn02ca_interrupt));
 589
 590        /* CPU IRQ priorities. */
 591        memcpy(&cpu_mask_nr_tbl, &kn02ca_cpu_mask_nr_tbl,
 592                sizeof(kn02ca_cpu_mask_nr_tbl));
 593
 594        /* I/O ASIC IRQ priorities. */
 595        memcpy(&asic_mask_nr_tbl, &kn02ca_asic_mask_nr_tbl,
 596                sizeof(kn02ca_asic_mask_nr_tbl));
 597
 598        mips_cpu_irq_init();
 599        init_ioasic_irqs(IO_IRQ_BASE);
 600
 601}                               /* dec_init_kn02ca */
 602
 603
 604/*
 605 * Machine-specific initialisation for KN03, aka DS5000/240,
 606 * aka 3max+ and DS5900, aka BIGmax.  Also applies to KN05, aka
 607 * DS5000/260, aka 4max+ and DS5900/260.
 608 */
 609static int kn03_interrupt[DEC_NR_INTS] __initdata = {
 610        [DEC_IRQ_CASCADE]       = DEC_CPU_IRQ_NR(KN03_CPU_INR_CASCADE),
 611        [DEC_IRQ_AB_RECV]       = -1,
 612        [DEC_IRQ_AB_XMIT]       = -1,
 613        [DEC_IRQ_DZ11]          = -1,
 614        [DEC_IRQ_ASC]           = IO_IRQ_NR(KN03_IO_INR_ASC),
 615        [DEC_IRQ_FLOPPY]        = -1,
 616        [DEC_IRQ_FPU]           = DEC_CPU_IRQ_NR(DEC_CPU_INR_FPU),
 617        [DEC_IRQ_HALT]          = DEC_CPU_IRQ_NR(KN03_CPU_INR_HALT),
 618        [DEC_IRQ_ISDN]          = -1,
 619        [DEC_IRQ_LANCE]         = IO_IRQ_NR(KN03_IO_INR_LANCE),
 620        [DEC_IRQ_BUS]           = DEC_CPU_IRQ_NR(KN03_CPU_INR_BUS),
 621        [DEC_IRQ_PSU]           = IO_IRQ_NR(KN03_IO_INR_PSU),
 622        [DEC_IRQ_RTC]           = DEC_CPU_IRQ_NR(KN03_CPU_INR_RTC),
 623        [DEC_IRQ_SCC0]          = IO_IRQ_NR(KN03_IO_INR_SCC0),
 624        [DEC_IRQ_SCC1]          = IO_IRQ_NR(KN03_IO_INR_SCC1),
 625        [DEC_IRQ_SII]           = -1,
 626        [DEC_IRQ_TC0]           = IO_IRQ_NR(KN03_IO_INR_TC0),
 627        [DEC_IRQ_TC1]           = IO_IRQ_NR(KN03_IO_INR_TC1),
 628        [DEC_IRQ_TC2]           = IO_IRQ_NR(KN03_IO_INR_TC2),
 629        [DEC_IRQ_TIMER]         = -1,
 630        [DEC_IRQ_VIDEO]         = -1,
 631        [DEC_IRQ_ASC_MERR]      = IO_IRQ_NR(IO_INR_ASC_MERR),
 632        [DEC_IRQ_ASC_ERR]       = IO_IRQ_NR(IO_INR_ASC_ERR),
 633        [DEC_IRQ_ASC_DMA]       = IO_IRQ_NR(IO_INR_ASC_DMA),
 634        [DEC_IRQ_FLOPPY_ERR]    = -1,
 635        [DEC_IRQ_ISDN_ERR]      = -1,
 636        [DEC_IRQ_ISDN_RXDMA]    = -1,
 637        [DEC_IRQ_ISDN_TXDMA]    = -1,
 638        [DEC_IRQ_LANCE_MERR]    = IO_IRQ_NR(IO_INR_LANCE_MERR),
 639        [DEC_IRQ_SCC0A_RXERR]   = IO_IRQ_NR(IO_INR_SCC0A_RXERR),
 640        [DEC_IRQ_SCC0A_RXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_RXDMA),
 641        [DEC_IRQ_SCC0A_TXERR]   = IO_IRQ_NR(IO_INR_SCC0A_TXERR),
 642        [DEC_IRQ_SCC0A_TXDMA]   = IO_IRQ_NR(IO_INR_SCC0A_TXDMA),
 643        [DEC_IRQ_AB_RXERR]      = -1,
 644        [DEC_IRQ_AB_RXDMA]      = -1,
 645        [DEC_IRQ_AB_TXERR]      = -1,
 646        [DEC_IRQ_AB_TXDMA]      = -1,
 647        [DEC_IRQ_SCC1A_RXERR]   = IO_IRQ_NR(IO_INR_SCC1A_RXERR),
 648        [DEC_IRQ_SCC1A_RXDMA]   = IO_IRQ_NR(IO_INR_SCC1A_RXDMA),
 649        [DEC_IRQ_SCC1A_TXERR]   = IO_IRQ_NR(IO_INR_SCC1A_TXERR),
 650        [DEC_IRQ_SCC1A_TXDMA]   = IO_IRQ_NR(IO_INR_SCC1A_TXDMA),
 651};
 652
 653static int_ptr kn03_cpu_mask_nr_tbl[][2] __initdata = {
 654        { { .i = DEC_CPU_IRQ_MASK(KN03_CPU_INR_BUS) },
 655                { .i = DEC_CPU_IRQ_NR(KN03_CPU_INR_BUS) } },
 656        { { .i = DEC_CPU_IRQ_MASK(KN03_CPU_INR_RTC) },
 657                { .i = DEC_CPU_IRQ_NR(KN03_CPU_INR_RTC) } },
 658        { { .i = DEC_CPU_IRQ_MASK(KN03_CPU_INR_CASCADE) },
 659                { .p = kn03_io_int } },
 660        { { .i = DEC_CPU_IRQ_ALL },
 661                { .p = cpu_all_int } },
 662};
 663
 664static int_ptr kn03_asic_mask_nr_tbl[][2] __initdata = {
 665        { { .i = IO_IRQ_DMA },
 666                { .p = asic_dma_int } },
 667        { { .i = IO_IRQ_MASK(KN03_IO_INR_SCC0) },
 668                { .i = IO_IRQ_NR(KN03_IO_INR_SCC0) } },
 669        { { .i = IO_IRQ_MASK(KN03_IO_INR_SCC1) },
 670                { .i = IO_IRQ_NR(KN03_IO_INR_SCC1) } },
 671        { { .i = IO_IRQ_MASK(KN03_IO_INR_ASC) },
 672                { .i = IO_IRQ_NR(KN03_IO_INR_ASC) } },
 673        { { .i = IO_IRQ_MASK(KN03_IO_INR_LANCE) },
 674                { .i = IO_IRQ_NR(KN03_IO_INR_LANCE) } },
 675        { { .i = IO_IRQ_MASK(KN03_IO_INR_TC2) },
 676                { .i = IO_IRQ_NR(KN03_IO_INR_TC2) } },
 677        { { .i = IO_IRQ_MASK(KN03_IO_INR_TC1) },
 678                { .i = IO_IRQ_NR(KN03_IO_INR_TC1) } },
 679        { { .i = IO_IRQ_MASK(KN03_IO_INR_TC0) },
 680                { .i = IO_IRQ_NR(KN03_IO_INR_TC0) } },
 681        { { .i = IO_IRQ_ALL },
 682                { .p = asic_all_int } },
 683};
 684
 685static void __init dec_init_kn03(void)
 686{
 687        /* IRQ routing. */
 688        memcpy(&dec_interrupt, &kn03_interrupt,
 689                sizeof(kn03_interrupt));
 690
 691        /* CPU IRQ priorities. */
 692        memcpy(&cpu_mask_nr_tbl, &kn03_cpu_mask_nr_tbl,
 693                sizeof(kn03_cpu_mask_nr_tbl));
 694
 695        /* I/O ASIC IRQ priorities. */
 696        memcpy(&asic_mask_nr_tbl, &kn03_asic_mask_nr_tbl,
 697                sizeof(kn03_asic_mask_nr_tbl));
 698
 699        mips_cpu_irq_init();
 700        init_ioasic_irqs(IO_IRQ_BASE);
 701
 702}                               /* dec_init_kn03 */
 703
 704
 705void __init arch_init_irq(void)
 706{
 707        switch (mips_machtype) {
 708        case MACH_DS23100:      /* DS2100/DS3100 Pmin/Pmax */
 709                dec_init_kn01();
 710                break;
 711        case MACH_DS5100:       /* DS5100 MIPSmate */
 712                dec_init_kn230();
 713                break;
 714        case MACH_DS5000_200:   /* DS5000/200 3max */
 715                dec_init_kn02();
 716                break;
 717        case MACH_DS5000_1XX:   /* DS5000/1xx 3min */
 718                dec_init_kn02ba();
 719                break;
 720        case MACH_DS5000_2X0:   /* DS5000/240 3max+ */
 721        case MACH_DS5900:       /* DS5900 bigmax */
 722                dec_init_kn03();
 723                break;
 724        case MACH_DS5000_XX:    /* Personal DS5000/xx */
 725                dec_init_kn02ca();
 726                break;
 727        case MACH_DS5800:       /* DS5800 Isis */
 728                panic("Don't know how to set this up!");
 729                break;
 730        case MACH_DS5400:       /* DS5400 MIPSfair */
 731                panic("Don't know how to set this up!");
 732                break;
 733        case MACH_DS5500:       /* DS5500 MIPSfair-2 */
 734                panic("Don't know how to set this up!");
 735                break;
 736        }
 737
 738        /* Free the FPU interrupt if the exception is present. */
 739        if (!cpu_has_nofpuex) {
 740                cpu_fpu_mask = 0;
 741                dec_interrupt[DEC_IRQ_FPU] = -1;
 742        }
 743        /* Free the halt interrupt unused on R4k systems.  */
 744        if (current_cpu_type() == CPU_R4000SC ||
 745            current_cpu_type() == CPU_R4400SC)
 746                dec_interrupt[DEC_IRQ_HALT] = -1;
 747
 748        /* Register board interrupts: FPU and cascade. */
 749        if (dec_interrupt[DEC_IRQ_FPU] >= 0 && cpu_has_fpu) {
 750                struct irq_desc *desc_fpu;
 751                int irq_fpu;
 752
 753                irq_fpu = dec_interrupt[DEC_IRQ_FPU];
 754                if (request_irq(irq_fpu, no_action, IRQF_NO_THREAD, "fpu",
 755                                NULL))
 756                        pr_err("Failed to register fpu interrupt\n");
 757                desc_fpu = irq_to_desc(irq_fpu);
 758                fpu_kstat_irq = this_cpu_ptr(desc_fpu->kstat_irqs);
 759        }
 760        if (dec_interrupt[DEC_IRQ_CASCADE] >= 0) {
 761                if (request_irq(dec_interrupt[DEC_IRQ_CASCADE], no_action,
 762                                IRQF_NO_THREAD, "cascade", NULL))
 763                        pr_err("Failed to register cascade interrupt\n");
 764        }
 765        /* Register the bus error interrupt. */
 766        if (dec_interrupt[DEC_IRQ_BUS] >= 0 && busirq_handler) {
 767                if (request_irq(dec_interrupt[DEC_IRQ_BUS], busirq_handler,
 768                                busirq_flags, "bus error", busirq_handler))
 769                        pr_err("Failed to register bus error interrupt\n");
 770        }
 771        /* Register the HALT interrupt. */
 772        if (dec_interrupt[DEC_IRQ_HALT] >= 0) {
 773                if (request_irq(dec_interrupt[DEC_IRQ_HALT], dec_intr_halt,
 774                                IRQF_NO_THREAD, "halt", NULL))
 775                        pr_err("Failed to register halt interrupt\n");
 776        }
 777}
 778
 779asmlinkage unsigned int dec_irq_dispatch(unsigned int irq)
 780{
 781        do_IRQ(irq);
 782        return 0;
 783}
 784