[TG3]: Set minimal hw interrupt mitigation.

[linux-2.6/verdex.git] / arch / m68k / atari / ataints.c

/*
 * arch/m68k/atari/ataints.c -- Atari Linux interrupt handling code
 *
 * 5/2/94 Roman Hodek:
 *  Added support for TT interrupts; setup for TT SCU (may someone has
 *  twiddled there and we won't get the right interrupts :-()
 *
 *  Major change: The device-independent code in m68k/ints.c didn't know
 *  about non-autovec ints yet. It hardcoded the number of possible ints to
 *  7 (IRQ1...IRQ7). But the Atari has lots of non-autovec ints! I made the
 *  number of possible ints a constant defined in interrupt.h, which is
 *  47 for the Atari. So we can call request_irq() for all Atari interrupts
 *  just the normal way. Additionally, all vectors >= 48 are initialized to
 *  call trap() instead of inthandler(). This must be changed here, too.
 *
 * 1995-07-16 Lars Brinkhoff <f93labr@dd.chalmers.se>:
 *  Corrected a bug in atari_add_isr() which rejected all SCC
 *  interrupt sources if there were no TT MFP!
 *
 * 12/13/95: New interface functions atari_level_triggered_int() and
 *  atari_register_vme_int() as support for level triggered VME interrupts.
 *
 * 02/12/96: (Roman)
 *  Total rewrite of Atari interrupt handling, for new scheme see comments
 *  below.
 *
 * 1996-09-03 lars brinkhoff <f93labr@dd.chalmers.se>:
 *  Added new function atari_unregister_vme_int(), and
 *  modified atari_register_vme_int() as well as IS_VALID_INTNO()
 *  to work with it.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 *
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/seq_file.h>

#include <asm/system.h>
#include <asm/traps.h>

#include <asm/atarihw.h>
#include <asm/atariints.h>
#include <asm/atari_stdma.h>
#include <asm/irq.h>
#include <asm/entry.h>


/*
 * Atari interrupt handling scheme:
 * --------------------------------
 *
 * All interrupt source have an internal number (defined in
 * <asm/atariints.h>): Autovector interrupts are 1..7, then follow ST-MFP,
 * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can
 * be allocated by atari_register_vme_int().
 *
 * Each interrupt can be of three types:
 *
 *  - SLOW: The handler runs with all interrupts enabled, except the one it
 *    was called by (to avoid reentering). This should be the usual method.
 *    But it is currently possible only for MFP ints, since only the MFP
 *    offers an easy way to mask interrupts.
 *
 *  - FAST: The handler runs with all interrupts disabled. This should be used
 *    only for really fast handlers, that just do actions immediately
 *    necessary, and let the rest do a bottom half or task queue.
 *
 *  - PRIORITIZED: The handler can be interrupted by higher-level ints
 *    (greater IPL, no MFP priorities!). This is the method of choice for ints
 *    which should be slow, but are not from a MFP.
 *
 * The feature of more than one handler for one int source is still there, but
 * only applicable if all handers are of the same type. To not slow down
 * processing of ints with only one handler by the chaining feature, the list
 * calling function atari_call_irq_list() is only plugged in at the time the
 * second handler is registered.
 *
 * Implementation notes: For fast-as-possible int handling, there are separate
 * entry points for each type (slow/fast/prio). The assembler handler calls
 * the irq directly in the usual case, no C wrapper is involved. In case of
 * multiple handlers, atari_call_irq_list() is registered as handler and calls
 * in turn the real irq's. To ease access from assembler level to the irq
 * function pointer and accompanying data, these two are stored in a separate
 * array, irq_handler[]. The rest of data (type, name) are put into a second
 * array, irq_param, that is accessed from C only. For each slow interrupt (32
 * in all) there are separate handler functions, which makes it possible to
 * hard-code the MFP register address and value, are necessary to mask the
 * int. If there'd be only one generic function, lots of calculations would be
 * needed to determine MFP register and int mask from the vector number :-(
 *
 * Furthermore, slow ints may not lower the IPL below its previous value
 * (before the int happened). This is needed so that an int of class PRIO, on
 * that this int may be stacked, cannot be reentered. This feature is
 * implemented as follows: If the stack frame format is 1 (throwaway), the int
 * is not stacked, and the IPL is anded with 0xfbff, resulting in a new level
 * 2, which still blocks the HSYNC, but no interrupts of interest. If the
 * frame format is 0, the int is nested, and the old IPL value can be found in
 * the sr copy in the frame.
 */


#define NUM_INT_SOURCES (8 + NUM_ATARI_SOURCES)

typedef void (*asm_irq_handler)(void);

struct irqhandler {
        irqreturn_t (*handler)(int, void *, struct pt_regs *);
        void    *dev_id;
};

struct irqparam {
        unsigned long   flags;
        const char      *devname;
};

/*
 * Array with irq's and their parameter data. This array is accessed from low
 * level assembler code, so an element size of 8 allows usage of index scaling
 * addressing mode.
 */
static struct irqhandler irq_handler[NUM_INT_SOURCES];

/*
 * This array hold the rest of parameters of int handlers: type
 * (slow,fast,prio) and the name of the handler. These values are only
 * accessed from C
 */
static struct irqparam irq_param[NUM_INT_SOURCES];

/*
 * Bitmap for free interrupt vector numbers
 * (new vectors starting from 0x70 can be allocated by
 * atari_register_vme_int())
 */
static int free_vme_vec_bitmap;

/* check for valid int number (complex, sigh...) */
#define IS_VALID_INTNO(n)                                                                                       \
        ((n) > 0 &&                                                                                                             \
         /* autovec and ST-MFP ok anyway */                                                             \
         (((n) < TTMFP_SOURCE_BASE) ||                                                                  \
          /* TT-MFP ok if present */                                                                    \
          ((n) >= TTMFP_SOURCE_BASE && (n) < SCC_SOURCE_BASE &&                 \
           ATARIHW_PRESENT(TT_MFP)) ||                                                                  \
          /* SCC ok if present and number even */                                               \
          ((n) >= SCC_SOURCE_BASE && (n) < VME_SOURCE_BASE &&                   \
           !((n) & 1) && ATARIHW_PRESENT(SCC)) ||                                               \
          /* greater numbers ok if they are registered VME vectors */           \
          ((n) >= VME_SOURCE_BASE && (n) < VME_SOURCE_BASE + VME_MAX_SOURCES && \
                  free_vme_vec_bitmap & (1 << ((n) - VME_SOURCE_BASE)))))


/*
 * Here start the assembler entry points for interrupts
 */

#define IRQ_NAME(nr) atari_slow_irq_##nr##_handler(void)

#define BUILD_SLOW_IRQ(n)                                                  \
asmlinkage void IRQ_NAME(n);                                               \
/* Dummy function to allow asm with operands.  */                          \
void atari_slow_irq_##n##_dummy (void) {                                   \
__asm__ (__ALIGN_STR "\n"                                                  \
"atari_slow_irq_" #n "_handler:\t"                                         \
"       addl    %6,%5\n"        /* preempt_count() += HARDIRQ_OFFSET */    \
        SAVE_ALL_INT "\n"                                                  \
        GET_CURRENT(%%d0) "\n"                                             \
"       andb    #~(1<<(%c3&7)),%a4:w\n" /* mask this interrupt */          \
        /* get old IPL from stack frame */                                 \
"       bfextu  %%sp@(%c2){#5,#3},%%d0\n"                                  \
"       movew   %%sr,%%d1\n"                                               \
"       bfins   %%d0,%%d1{#21,#3}\n"                                       \
"       movew   %%d1,%%sr\n"            /* set IPL = previous value */     \
"       addql   #1,%a0\n"                                                  \
"       lea     %a1,%%a0\n"                                                \
"       pea     %%sp@\n"                /* push addr of frame */           \
"       movel   %%a0@(4),%%sp@-\n"      /* push handler data */            \
"       pea     (%c3+8)\n"              /* push int number */              \
"       movel   %%a0@,%%a0\n"                                              \
"       jbsr    %%a0@\n"                /* call the handler */             \
"       addql   #8,%%sp\n"                                                 \
"       addql   #4,%%sp\n"                                                 \
"       orw     #0x0600,%%sr\n"                                            \
"       andw    #0xfeff,%%sr\n"         /* set IPL = 6 again */            \
"       orb     #(1<<(%c3&7)),%a4:w\n"  /* now unmask the int again */     \
"       jbra    ret_from_interrupt\n"                                      \
         : : "i" (&kstat_cpu(0).irqs[n+8]), "i" (&irq_handler[n+8]),       \
             "n" (PT_OFF_SR), "n" (n),                                     \
             "i" (n & 8 ? (n & 16 ? &tt_mfp.int_mk_a : &mfp.int_mk_a)      \
                        : (n & 16 ? &tt_mfp.int_mk_b : &mfp.int_mk_b)),    \
             "m" (preempt_count()), "di" (HARDIRQ_OFFSET)                  \
);                                                                         \
        for (;;);                       /* fake noreturn */                \
}

BUILD_SLOW_IRQ(0);
BUILD_SLOW_IRQ(1);
BUILD_SLOW_IRQ(2);
BUILD_SLOW_IRQ(3);
BUILD_SLOW_IRQ(4);
BUILD_SLOW_IRQ(5);
BUILD_SLOW_IRQ(6);
BUILD_SLOW_IRQ(7);
BUILD_SLOW_IRQ(8);
BUILD_SLOW_IRQ(9);
BUILD_SLOW_IRQ(10);
BUILD_SLOW_IRQ(11);
BUILD_SLOW_IRQ(12);
BUILD_SLOW_IRQ(13);
BUILD_SLOW_IRQ(14);
BUILD_SLOW_IRQ(15);
BUILD_SLOW_IRQ(16);
BUILD_SLOW_IRQ(17);
BUILD_SLOW_IRQ(18);
BUILD_SLOW_IRQ(19);
BUILD_SLOW_IRQ(20);
BUILD_SLOW_IRQ(21);
BUILD_SLOW_IRQ(22);
BUILD_SLOW_IRQ(23);
BUILD_SLOW_IRQ(24);
BUILD_SLOW_IRQ(25);
BUILD_SLOW_IRQ(26);
BUILD_SLOW_IRQ(27);
BUILD_SLOW_IRQ(28);
BUILD_SLOW_IRQ(29);
BUILD_SLOW_IRQ(30);
BUILD_SLOW_IRQ(31);

asm_irq_handler slow_handlers[32] = {
        [0]     = atari_slow_irq_0_handler,
        [1]     = atari_slow_irq_1_handler,
        [2]     = atari_slow_irq_2_handler,
        [3]     = atari_slow_irq_3_handler,
        [4]     = atari_slow_irq_4_handler,
        [5]     = atari_slow_irq_5_handler,
        [6]     = atari_slow_irq_6_handler,
        [7]     = atari_slow_irq_7_handler,
        [8]     = atari_slow_irq_8_handler,
        [9]     = atari_slow_irq_9_handler,
        [10]    = atari_slow_irq_10_handler,
        [11]    = atari_slow_irq_11_handler,
        [12]    = atari_slow_irq_12_handler,
        [13]    = atari_slow_irq_13_handler,
        [14]    = atari_slow_irq_14_handler,
        [15]    = atari_slow_irq_15_handler,
        [16]    = atari_slow_irq_16_handler,
        [17]    = atari_slow_irq_17_handler,
        [18]    = atari_slow_irq_18_handler,
        [19]    = atari_slow_irq_19_handler,
        [20]    = atari_slow_irq_20_handler,
        [21]    = atari_slow_irq_21_handler,
        [22]    = atari_slow_irq_22_handler,
        [23]    = atari_slow_irq_23_handler,
        [24]    = atari_slow_irq_24_handler,
        [25]    = atari_slow_irq_25_handler,
        [26]    = atari_slow_irq_26_handler,
        [27]    = atari_slow_irq_27_handler,
        [28]    = atari_slow_irq_28_handler,
        [29]    = atari_slow_irq_29_handler,
        [30]    = atari_slow_irq_30_handler,
        [31]    = atari_slow_irq_31_handler
};

asmlinkage void atari_fast_irq_handler( void );
asmlinkage void atari_prio_irq_handler( void );

/* Dummy function to allow asm with operands.  */
void atari_fast_prio_irq_dummy (void) {
__asm__ (__ALIGN_STR "\n"
"atari_fast_irq_handler:\n\t"
        "orw    #0x700,%%sr\n"          /* disable all interrupts */
"atari_prio_irq_handler:\n\t"
        "addl   %3,%2\n\t"              /* preempt_count() += HARDIRQ_OFFSET */
        SAVE_ALL_INT "\n\t"
        GET_CURRENT(%%d0) "\n\t"
        /* get vector number from stack frame and convert to source */
        "bfextu %%sp@(%c1){#4,#10},%%d0\n\t"
        "subw   #(0x40-8),%%d0\n\t"
        "jpl    1f\n\t"
        "addw   #(0x40-8-0x18),%%d0\n"
    "1:\tlea    %a0,%%a0\n\t"
        "addql  #1,%%a0@(%%d0:l:4)\n\t"
        "lea    irq_handler,%%a0\n\t"
        "lea    %%a0@(%%d0:l:8),%%a0\n\t"
        "pea    %%sp@\n\t"              /* push frame address */
        "movel  %%a0@(4),%%sp@-\n\t"    /* push handler data */
        "movel  %%d0,%%sp@-\n\t"        /* push int number */
        "movel  %%a0@,%%a0\n\t"
        "jsr    %%a0@\n\t"              /* and call the handler */
        "addql  #8,%%sp\n\t"
        "addql  #4,%%sp\n\t"
        "jbra   ret_from_interrupt"
         : : "i" (&kstat_cpu(0).irqs), "n" (PT_OFF_FORMATVEC),
             "m" (preempt_count()), "di" (HARDIRQ_OFFSET)
);
        for (;;);
}

/* GK:
 * HBL IRQ handler for Falcon. Nobody needs it :-)
 * ++andreas: raise ipl to disable further HBLANK interrupts.
 */
asmlinkage void falcon_hblhandler(void);
asm(".text\n"
__ALIGN_STR "\n\t"
"falcon_hblhandler:\n\t"
        "orw    #0x200,%sp@\n\t"        /* set saved ipl to 2 */
        "rte");

/* Defined in entry.S; only increments 'num_spurious' */
asmlinkage void bad_interrupt(void);

extern void atari_microwire_cmd( int cmd );

extern int atari_SCC_reset_done;

/*
 * void atari_init_IRQ (void)
 *
 * Parameters:  None
 *
 * Returns:     Nothing
 *
 * This function should be called during kernel startup to initialize
 * the atari IRQ handling routines.
 */

void __init atari_init_IRQ(void)
{
        int i;

        /* initialize the vector table */
        for (i = 0; i < NUM_INT_SOURCES; ++i) {
                vectors[IRQ_SOURCE_TO_VECTOR(i)] = bad_interrupt;
        }

        /* Initialize the MFP(s) */

#ifdef ATARI_USE_SOFTWARE_EOI
        mfp.vec_adr  = 0x48;    /* Software EOI-Mode */
#else
        mfp.vec_adr  = 0x40;    /* Automatic EOI-Mode */
#endif
        mfp.int_en_a = 0x00;    /* turn off MFP-Ints */
        mfp.int_en_b = 0x00;
        mfp.int_mk_a = 0xff;    /* no Masking */
        mfp.int_mk_b = 0xff;

        if (ATARIHW_PRESENT(TT_MFP)) {
#ifdef ATARI_USE_SOFTWARE_EOI
                tt_mfp.vec_adr  = 0x58;         /* Software EOI-Mode */
#else
                tt_mfp.vec_adr  = 0x50;         /* Automatic EOI-Mode */
#endif
                tt_mfp.int_en_a = 0x00;         /* turn off MFP-Ints */
                tt_mfp.int_en_b = 0x00;
                tt_mfp.int_mk_a = 0xff;         /* no Masking */
                tt_mfp.int_mk_b = 0xff;
        }

        if (ATARIHW_PRESENT(SCC) && !atari_SCC_reset_done) {
                scc.cha_a_ctrl = 9;
                MFPDELAY();
                scc.cha_a_ctrl = (char) 0xc0; /* hardware reset */
        }

        if (ATARIHW_PRESENT(SCU)) {
                /* init the SCU if present */
                tt_scu.sys_mask = 0x10;         /* enable VBL (for the cursor) and
                                                                         * disable HSYNC interrupts (who
                                                                         * needs them?)  MFP and SCC are
                                                                         * enabled in VME mask
                                                                         */
                tt_scu.vme_mask = 0x60;         /* enable MFP and SCC ints */
        }
        else {
                /* If no SCU and no Hades, the HSYNC interrupt needs to be
                 * disabled this way. (Else _inthandler in kernel/sys_call.S
                 * gets overruns)
                 */

                if (!MACH_IS_HADES)
                        vectors[VEC_INT2] = falcon_hblhandler;
        }

        if (ATARIHW_PRESENT(PCM_8BIT) && ATARIHW_PRESENT(MICROWIRE)) {
                /* Initialize the LM1992 Sound Controller to enable
                   the PSG sound.  This is misplaced here, it should
                   be in an atasound_init(), that doesn't exist yet. */
                atari_microwire_cmd(MW_LM1992_PSG_HIGH);
        }

        stdma_init();

        /* Initialize the PSG: all sounds off, both ports output */
        sound_ym.rd_data_reg_sel = 7;
        sound_ym.wd_data = 0xff;
}


static irqreturn_t atari_call_irq_list( int irq, void *dev_id, struct pt_regs *fp )
{
        irq_node_t *node;

        for (node = (irq_node_t *)dev_id; node; node = node->next)
                node->handler(irq, node->dev_id, fp);
        return IRQ_HANDLED;
}


/*
 * atari_request_irq : add an interrupt service routine for a particular
 *                     machine specific interrupt source.
 *                     If the addition was successful, it returns 0.
 */

int atari_request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *),
                      unsigned long flags, const char *devname, void *dev_id)
{
        int vector;
        unsigned long oflags = flags;

        /*
         * The following is a hack to make some PCI card drivers work,
         * which set the SA_SHIRQ flag.
         */

        flags &= ~SA_SHIRQ;

        if (flags == SA_INTERRUPT) {
                printk ("%s: SA_INTERRUPT changed to IRQ_TYPE_SLOW for %s\n",
                        __FUNCTION__, devname);
                flags = IRQ_TYPE_SLOW;
        }
        if (flags < IRQ_TYPE_SLOW || flags > IRQ_TYPE_PRIO) {
                printk ("%s: Bad irq type 0x%lx <0x%lx> requested from %s\n",
                        __FUNCTION__, flags, oflags, devname);
                return -EINVAL;
        }
        if (!IS_VALID_INTNO(irq)) {
                printk ("%s: Unknown irq %d requested from %s\n",
                        __FUNCTION__, irq, devname);
                return -ENXIO;
        }
        vector = IRQ_SOURCE_TO_VECTOR(irq);

        /*
         * Check type/source combination: slow ints are (currently)
         * only possible for MFP-interrupts.
         */
        if (flags == IRQ_TYPE_SLOW &&
                (irq < STMFP_SOURCE_BASE || irq >= SCC_SOURCE_BASE)) {
                printk ("%s: Slow irq requested for non-MFP source %d from %s\n",
                        __FUNCTION__, irq, devname);
                return -EINVAL;
        }

        if (vectors[vector] == bad_interrupt) {
                /* int has no handler yet */
                irq_handler[irq].handler = handler;
                irq_handler[irq].dev_id  = dev_id;
                irq_param[irq].flags   = flags;
                irq_param[irq].devname = devname;
                vectors[vector] =
                        (flags == IRQ_TYPE_SLOW) ? slow_handlers[irq-STMFP_SOURCE_BASE] :
                        (flags == IRQ_TYPE_FAST) ? atari_fast_irq_handler :
                                                  atari_prio_irq_handler;
                /* If MFP int, also enable and umask it */
                atari_turnon_irq(irq);
                atari_enable_irq(irq);

                return 0;
        }
        else if (irq_param[irq].flags == flags) {
                /* old handler is of same type -> handlers can be chained */
                irq_node_t *node;
                unsigned long flags;

                local_irq_save(flags);

                if (irq_handler[irq].handler != atari_call_irq_list) {
                        /* Only one handler yet, make a node for this first one */
                        if (!(node = new_irq_node()))
                                return -ENOMEM;
                        node->handler = irq_handler[irq].handler;
                        node->dev_id  = irq_handler[irq].dev_id;
                        node->devname = irq_param[irq].devname;
                        node->next = NULL;

                        irq_handler[irq].handler = atari_call_irq_list;
                        irq_handler[irq].dev_id  = node;
                        irq_param[irq].devname   = "chained";
                }

                if (!(node = new_irq_node()))
                        return -ENOMEM;
                node->handler = handler;
                node->dev_id  = dev_id;
                node->devname = devname;
                /* new handlers are put in front of the queue */
                node->next = irq_handler[irq].dev_id;
                irq_handler[irq].dev_id = node;

                local_irq_restore(flags);
                return 0;
        } else {
                printk ("%s: Irq %d allocated by other type int (call from %s)\n",
                        __FUNCTION__, irq, devname);
                return -EBUSY;
        }
}

void atari_free_irq(unsigned int irq, void *dev_id)
{
        unsigned long flags;
        int vector;
        irq_node_t **list, *node;

        if (!IS_VALID_INTNO(irq)) {
                printk("%s: Unknown irq %d\n", __FUNCTION__, irq);
                return;
        }

        vector = IRQ_SOURCE_TO_VECTOR(irq);
        if (vectors[vector] == bad_interrupt)
                goto not_found;

        local_irq_save(flags);

        if (irq_handler[irq].handler != atari_call_irq_list) {
                /* It's the only handler for the interrupt */
                if (irq_handler[irq].dev_id != dev_id) {
                        local_irq_restore(flags);
                        goto not_found;
                }
                irq_handler[irq].handler = NULL;
                irq_handler[irq].dev_id  = NULL;
                irq_param[irq].devname   = NULL;
                vectors[vector] = bad_interrupt;
                /* If MFP int, also disable it */
                atari_disable_irq(irq);
                atari_turnoff_irq(irq);

                local_irq_restore(flags);
                return;
        }

        /* The interrupt is chained, find the irq on the list */
        for(list = (irq_node_t **)&irq_handler[irq].dev_id; *list; list = &(*list)->next) {
                if ((*list)->dev_id == dev_id) break;
        }
        if (!*list) {
                local_irq_restore(flags);
                goto not_found;
        }

        (*list)->handler = NULL; /* Mark it as free for reallocation */
        *list = (*list)->next;

        /* If there's now only one handler, unchain the interrupt, i.e. plug in
         * the handler directly again and omit atari_call_irq_list */
        node = (irq_node_t *)irq_handler[irq].dev_id;
        if (node && !node->next) {
                irq_handler[irq].handler = node->handler;
                irq_handler[irq].dev_id  = node->dev_id;
                irq_param[irq].devname   = node->devname;
                node->handler = NULL; /* Mark it as free for reallocation */
        }

        local_irq_restore(flags);
        return;

not_found:
        printk("%s: tried to remove invalid irq\n", __FUNCTION__);
        return;
}


/*
 * atari_register_vme_int() returns the number of a free interrupt vector for
 * hardware with a programmable int vector (probably a VME board).
 */

unsigned long atari_register_vme_int(void)
{
        int i;

        for(i = 0; i < 32; i++)
                if((free_vme_vec_bitmap & (1 << i)) == 0)
                        break;

        if(i == 16)
                return 0;

        free_vme_vec_bitmap |= 1 << i;
        return (VME_SOURCE_BASE + i);
}


void atari_unregister_vme_int(unsigned long irq)
{
        if(irq >= VME_SOURCE_BASE && irq < VME_SOURCE_BASE + VME_MAX_SOURCES) {
                irq -= VME_SOURCE_BASE;
                free_vme_vec_bitmap &= ~(1 << irq);
        }
}


int show_atari_interrupts(struct seq_file *p, void *v)
{
        int i;

        for (i = 0; i < NUM_INT_SOURCES; ++i) {
                if (vectors[IRQ_SOURCE_TO_VECTOR(i)] == bad_interrupt)
                        continue;
                if (i < STMFP_SOURCE_BASE)
                        seq_printf(p, "auto %2d: %10u ",
                                       i, kstat_cpu(0).irqs[i]);
                else
                        seq_printf(p, "vec $%02x: %10u ",
                                       IRQ_SOURCE_TO_VECTOR(i),
                                       kstat_cpu(0).irqs[i]);

                if (irq_handler[i].handler != atari_call_irq_list) {
                        seq_printf(p, "%s\n", irq_param[i].devname);
                }
                else {
                        irq_node_t *n;
                        for( n = (irq_node_t *)irq_handler[i].dev_id; n; n = n->next ) {
                                seq_printf(p, "%s\n", n->devname);
                                if (n->next)
                                        seq_puts(p, "                    " );
                        }
                }
        }
        if (num_spurious)
                seq_printf(p, "spurio.: %10u\n", num_spurious);

        return 0;
}