[qemu.git] / hw / openpic.c

/*
 * OpenPIC emulation
 *
 * Copyright (c) 2004 Jocelyn Mayer
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
/*
 *
 * Based on OpenPic implementations:
 * - Intel GW80314 I/O companion chip developer's manual
 * - Motorola MPC8245 & MPC8540 user manuals.
 * - Motorola MCP750 (aka Raven) programmer manual.
 * - Motorola Harrier programmer manuel
 *
 * Serial interrupts, as implemented in Raven chipset are not supported yet.
 *
 */
#include "hw.h"
#include "ppc_mac.h"
#include "pci.h"
#include "openpic.h"

//#define DEBUG_OPENPIC

#ifdef DEBUG_OPENPIC
#define DPRINTF(fmt, ...) do { printf(fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do { } while (0)
#endif

#define USE_MPCxxx /* Intel model is broken, for now */

#if defined (USE_INTEL_GW80314)
/* Intel GW80314 I/O Companion chip */

#define MAX_CPU     4
#define MAX_IRQ    32
#define MAX_DBL     4
#define MAX_MBX     4
#define MAX_TMR     4
#define VECTOR_BITS 8
#define MAX_IPI     0

#define VID (0x00000000)

#elif defined(USE_MPCxxx)

#define MAX_CPU     2
#define MAX_IRQ   128
#define MAX_DBL     0
#define MAX_MBX     0
#define MAX_TMR     4
#define VECTOR_BITS 8
#define MAX_IPI     4
#define VID         0x03 /* MPIC version ID */
#define VENI        0x00000000 /* Vendor ID */

enum {
    IRQ_IPVP = 0,
    IRQ_IDE,
};

/* OpenPIC */
#define OPENPIC_MAX_CPU      2
#define OPENPIC_MAX_IRQ     64
#define OPENPIC_EXT_IRQ     48
#define OPENPIC_MAX_TMR      MAX_TMR
#define OPENPIC_MAX_IPI      MAX_IPI

/* Interrupt definitions */
#define OPENPIC_IRQ_FE     (OPENPIC_EXT_IRQ)     /* Internal functional IRQ */
#define OPENPIC_IRQ_ERR    (OPENPIC_EXT_IRQ + 1) /* Error IRQ */
#define OPENPIC_IRQ_TIM0   (OPENPIC_EXT_IRQ + 2) /* First timer IRQ */
#if OPENPIC_MAX_IPI > 0
#define OPENPIC_IRQ_IPI0   (OPENPIC_IRQ_TIM0 + OPENPIC_MAX_TMR) /* First IPI IRQ */
#define OPENPIC_IRQ_DBL0   (OPENPIC_IRQ_IPI0 + (OPENPIC_MAX_CPU * OPENPIC_MAX_IPI)) /* First doorbell IRQ */
#else
#define OPENPIC_IRQ_DBL0   (OPENPIC_IRQ_TIM0 + OPENPIC_MAX_TMR) /* First doorbell IRQ */
#define OPENPIC_IRQ_MBX0   (OPENPIC_IRQ_DBL0 + OPENPIC_MAX_DBL) /* First mailbox IRQ */
#endif

/* MPIC */
#define MPIC_MAX_CPU      1
#define MPIC_MAX_EXT     12
#define MPIC_MAX_INT     64
#define MPIC_MAX_MSG      4
#define MPIC_MAX_MSI      8
#define MPIC_MAX_TMR      MAX_TMR
#define MPIC_MAX_IPI      MAX_IPI
#define MPIC_MAX_IRQ     (MPIC_MAX_EXT + MPIC_MAX_INT + MPIC_MAX_TMR + MPIC_MAX_MSG + MPIC_MAX_MSI + (MPIC_MAX_IPI * MPIC_MAX_CPU))

/* Interrupt definitions */
#define MPIC_EXT_IRQ      0
#define MPIC_INT_IRQ      (MPIC_EXT_IRQ + MPIC_MAX_EXT)
#define MPIC_TMR_IRQ      (MPIC_INT_IRQ + MPIC_MAX_INT)
#define MPIC_MSG_IRQ      (MPIC_TMR_IRQ + MPIC_MAX_TMR)
#define MPIC_MSI_IRQ      (MPIC_MSG_IRQ + MPIC_MAX_MSG)
#define MPIC_IPI_IRQ      (MPIC_MSI_IRQ + MPIC_MAX_MSI)

#define MPIC_GLB_REG_START        0x0
#define MPIC_GLB_REG_SIZE         0x10F0
#define MPIC_TMR_REG_START        0x10F0
#define MPIC_TMR_REG_SIZE         0x220
#define MPIC_EXT_REG_START        0x10000
#define MPIC_EXT_REG_SIZE         0x180
#define MPIC_INT_REG_START        0x10200
#define MPIC_INT_REG_SIZE         0x800
#define MPIC_MSG_REG_START        0x11600
#define MPIC_MSG_REG_SIZE         0x100
#define MPIC_MSI_REG_START        0x11C00
#define MPIC_MSI_REG_SIZE         0x100
#define MPIC_CPU_REG_START        0x20000
#define MPIC_CPU_REG_SIZE         0x100

enum mpic_ide_bits {
    IDR_EP     = 0,
    IDR_CI0     = 1,
    IDR_CI1     = 2,
    IDR_P1     = 30,
    IDR_P0     = 31,
};

#else
#error "Please select which OpenPic implementation is to be emulated"
#endif

#define OPENPIC_PAGE_SIZE 4096

#define BF_WIDTH(_bits_) \
(((_bits_) + (sizeof(uint32_t) * 8) - 1) / (sizeof(uint32_t) * 8))

static inline void set_bit (uint32_t *field, int bit)
{
    field[bit >> 5] |= 1 << (bit & 0x1F);
}

static inline void reset_bit (uint32_t *field, int bit)
{
    field[bit >> 5] &= ~(1 << (bit & 0x1F));
}

static inline int test_bit (uint32_t *field, int bit)
{
    return (field[bit >> 5] & 1 << (bit & 0x1F)) != 0;
}

enum {
    IRQ_EXTERNAL = 0x01,
    IRQ_INTERNAL = 0x02,
    IRQ_TIMER    = 0x04,
    IRQ_SPECIAL  = 0x08,
};

typedef struct IRQ_queue_t {
    uint32_t queue[BF_WIDTH(MAX_IRQ)];
    int next;
    int priority;
} IRQ_queue_t;

typedef struct IRQ_src_t {
    uint32_t ipvp;  /* IRQ vector/priority register */
    uint32_t ide;   /* IRQ destination register */
    int type;
    int last_cpu;
    int pending;    /* TRUE if IRQ is pending */
} IRQ_src_t;

enum IPVP_bits {
    IPVP_MASK     = 31,
    IPVP_ACTIVITY = 30,
    IPVP_MODE     = 29,
    IPVP_POLARITY = 23,
    IPVP_SENSE    = 22,
};
#define IPVP_PRIORITY_MASK     (0x1F << 16)
#define IPVP_PRIORITY(_ipvpr_) ((int)(((_ipvpr_) & IPVP_PRIORITY_MASK) >> 16))
#define IPVP_VECTOR_MASK       ((1 << VECTOR_BITS) - 1)
#define IPVP_VECTOR(_ipvpr_)   ((_ipvpr_) & IPVP_VECTOR_MASK)

typedef struct IRQ_dst_t {
    uint32_t tfrr;
    uint32_t pctp; /* CPU current task priority */
    uint32_t pcsr; /* CPU sensitivity register */
    IRQ_queue_t raised;
    IRQ_queue_t servicing;
    qemu_irq *irqs;
} IRQ_dst_t;

typedef struct openpic_t {
    PCIDevice pci_dev;
    int mem_index;
    /* Global registers */
    uint32_t frep; /* Feature reporting register */
    uint32_t glbc; /* Global configuration register  */
    uint32_t micr; /* MPIC interrupt configuration register */
    uint32_t veni; /* Vendor identification register */
    uint32_t pint; /* Processor initialization register */
    uint32_t spve; /* Spurious vector register */
    uint32_t tifr; /* Timer frequency reporting register */
    /* Source registers */
    IRQ_src_t src[MAX_IRQ];
    /* Local registers per output pin */
    IRQ_dst_t dst[MAX_CPU];
    int nb_cpus;
    /* Timer registers */
    struct {
        uint32_t ticc;  /* Global timer current count register */
        uint32_t tibc;  /* Global timer base count register */
    } timers[MAX_TMR];
#if MAX_DBL > 0
    /* Doorbell registers */
    uint32_t dar;        /* Doorbell activate register */
    struct {
        uint32_t dmr;    /* Doorbell messaging register */
    } doorbells[MAX_DBL];
#endif
#if MAX_MBX > 0
    /* Mailbox registers */
    struct {
        uint32_t mbr;    /* Mailbox register */
    } mailboxes[MAX_MAILBOXES];
#endif
    /* IRQ out is used when in bypass mode (not implemented) */
    qemu_irq irq_out;
    int max_irq;
    int irq_ipi0;
    int irq_tim0;
    void (*reset) (void *);
    void (*irq_raise) (struct openpic_t *, int, IRQ_src_t *);
} openpic_t;

static inline void IRQ_setbit (IRQ_queue_t *q, int n_IRQ)
{
    set_bit(q->queue, n_IRQ);
}

static inline void IRQ_resetbit (IRQ_queue_t *q, int n_IRQ)
{
    reset_bit(q->queue, n_IRQ);
}

static inline int IRQ_testbit (IRQ_queue_t *q, int n_IRQ)
{
    return test_bit(q->queue, n_IRQ);
}

static void IRQ_check (openpic_t *opp, IRQ_queue_t *q)
{
    int next, i;
    int priority;

    next = -1;
    priority = -1;
    for (i = 0; i < opp->max_irq; i++) {
        if (IRQ_testbit(q, i)) {
            DPRINTF("IRQ_check: irq %d set ipvp_pr=%d pr=%d\n",
                    i, IPVP_PRIORITY(opp->src[i].ipvp), priority);
            if (IPVP_PRIORITY(opp->src[i].ipvp) > priority) {
                next = i;
                priority = IPVP_PRIORITY(opp->src[i].ipvp);
            }
        }
    }
    q->next = next;
    q->priority = priority;
}

static int IRQ_get_next (openpic_t *opp, IRQ_queue_t *q)
{
    if (q->next == -1) {
        /* XXX: optimize */
        IRQ_check(opp, q);
    }

    return q->next;
}

static void IRQ_local_pipe (openpic_t *opp, int n_CPU, int n_IRQ)
{
    IRQ_dst_t *dst;
    IRQ_src_t *src;
    int priority;

    dst = &opp->dst[n_CPU];
    src = &opp->src[n_IRQ];
    priority = IPVP_PRIORITY(src->ipvp);
    if (priority <= dst->pctp) {
        /* Too low priority */
        DPRINTF("%s: IRQ %d has too low priority on CPU %d\n",
                __func__, n_IRQ, n_CPU);
        return;
    }
    if (IRQ_testbit(&dst->raised, n_IRQ)) {
        /* Interrupt miss */
        DPRINTF("%s: IRQ %d was missed on CPU %d\n",
                __func__, n_IRQ, n_CPU);
        return;
    }
    set_bit(&src->ipvp, IPVP_ACTIVITY);
    IRQ_setbit(&dst->raised, n_IRQ);
    if (priority < dst->raised.priority) {
        /* An higher priority IRQ is already raised */
        DPRINTF("%s: IRQ %d is hidden by raised IRQ %d on CPU %d\n",
                __func__, n_IRQ, dst->raised.next, n_CPU);
        return;
    }
    IRQ_get_next(opp, &dst->raised);
    if (IRQ_get_next(opp, &dst->servicing) != -1 &&
        priority <= dst->servicing.priority) {
        DPRINTF("%s: IRQ %d is hidden by servicing IRQ %d on CPU %d\n",
                __func__, n_IRQ, dst->servicing.next, n_CPU);
        /* Already servicing a higher priority IRQ */
        return;
    }
    DPRINTF("Raise OpenPIC INT output cpu %d irq %d\n", n_CPU, n_IRQ);
    opp->irq_raise(opp, n_CPU, src);
}

/* update pic state because registers for n_IRQ have changed value */
static void openpic_update_irq(openpic_t *opp, int n_IRQ)
{
    IRQ_src_t *src;
    int i;

    src = &opp->src[n_IRQ];

    if (!src->pending) {
        /* no irq pending */
        DPRINTF("%s: IRQ %d is not pending\n", __func__, n_IRQ);
        return;
    }
    if (test_bit(&src->ipvp, IPVP_MASK)) {
        /* Interrupt source is disabled */
        DPRINTF("%s: IRQ %d is disabled\n", __func__, n_IRQ);
        return;
    }
    if (IPVP_PRIORITY(src->ipvp) == 0) {
        /* Priority set to zero */
        DPRINTF("%s: IRQ %d has 0 priority\n", __func__, n_IRQ);
        return;
    }
    if (test_bit(&src->ipvp, IPVP_ACTIVITY)) {
        /* IRQ already active */
        DPRINTF("%s: IRQ %d is already active\n", __func__, n_IRQ);
        return;
    }
    if (src->ide == 0x00000000) {
        /* No target */
        DPRINTF("%s: IRQ %d has no target\n", __func__, n_IRQ);
        return;
    }

    if (src->ide == (1 << src->last_cpu)) {
        /* Only one CPU is allowed to receive this IRQ */
        IRQ_local_pipe(opp, src->last_cpu, n_IRQ);
    } else if (!test_bit(&src->ipvp, IPVP_MODE)) {
        /* Directed delivery mode */
        for (i = 0; i < opp->nb_cpus; i++) {
            if (test_bit(&src->ide, i))
                IRQ_local_pipe(opp, i, n_IRQ);
        }
    } else {
        /* Distributed delivery mode */
        for (i = src->last_cpu + 1; i != src->last_cpu; i++) {
            if (i == opp->nb_cpus)
                i = 0;
            if (test_bit(&src->ide, i)) {
                IRQ_local_pipe(opp, i, n_IRQ);
                src->last_cpu = i;
                break;
            }
        }
    }
}

static void openpic_set_irq(void *opaque, int n_IRQ, int level)
{
    openpic_t *opp = opaque;
    IRQ_src_t *src;

    src = &opp->src[n_IRQ];
    DPRINTF("openpic: set irq %d = %d ipvp=%08x\n",
            n_IRQ, level, src->ipvp);
    if (test_bit(&src->ipvp, IPVP_SENSE)) {
        /* level-sensitive irq */
        src->pending = level;
        if (!level)
            reset_bit(&src->ipvp, IPVP_ACTIVITY);
    } else {
        /* edge-sensitive irq */
        if (level)
            src->pending = 1;
    }
    openpic_update_irq(opp, n_IRQ);
}

static void openpic_reset (void *opaque)
{
    openpic_t *opp = (openpic_t *)opaque;
    int i;

    opp->glbc = 0x80000000;
    /* Initialise controller registers */
    opp->frep = ((OPENPIC_EXT_IRQ - 1) << 16) | ((MAX_CPU - 1) << 8) | VID;
    opp->veni = VENI;
    opp->pint = 0x00000000;
    opp->spve = 0x000000FF;
    opp->tifr = 0x003F7A00;
    /* ? */
    opp->micr = 0x00000000;
    /* Initialise IRQ sources */
    for (i = 0; i < opp->max_irq; i++) {
        opp->src[i].ipvp = 0xA0000000;
        opp->src[i].ide  = 0x00000000;
    }
    /* Initialise IRQ destinations */
    for (i = 0; i < MAX_CPU; i++) {
        opp->dst[i].pctp      = 0x0000000F;
        opp->dst[i].pcsr      = 0x00000000;
        memset(&opp->dst[i].raised, 0, sizeof(IRQ_queue_t));
        opp->dst[i].raised.next = -1;
        memset(&opp->dst[i].servicing, 0, sizeof(IRQ_queue_t));
        opp->dst[i].servicing.next = -1;
    }
    /* Initialise timers */
    for (i = 0; i < MAX_TMR; i++) {
        opp->timers[i].ticc = 0x00000000;
        opp->timers[i].tibc = 0x80000000;
    }
    /* Initialise doorbells */
#if MAX_DBL > 0
    opp->dar = 0x00000000;
    for (i = 0; i < MAX_DBL; i++) {
        opp->doorbells[i].dmr  = 0x00000000;
    }
#endif
    /* Initialise mailboxes */
#if MAX_MBX > 0
    for (i = 0; i < MAX_MBX; i++) { /* ? */
        opp->mailboxes[i].mbr   = 0x00000000;
    }
#endif
    /* Go out of RESET state */
    opp->glbc = 0x00000000;
}

static inline uint32_t read_IRQreg (openpic_t *opp, int n_IRQ, uint32_t reg)
{
    uint32_t retval;

    switch (reg) {
    case IRQ_IPVP:
        retval = opp->src[n_IRQ].ipvp;
        break;
    case IRQ_IDE:
        retval = opp->src[n_IRQ].ide;
        break;
    }

    return retval;
}

static inline void write_IRQreg (openpic_t *opp, int n_IRQ,
                                 uint32_t reg, uint32_t val)
{
    uint32_t tmp;

    switch (reg) {
    case IRQ_IPVP:
        /* NOTE: not fully accurate for special IRQs, but simple and
           sufficient */
        /* ACTIVITY bit is read-only */
        opp->src[n_IRQ].ipvp =
            (opp->src[n_IRQ].ipvp & 0x40000000) |
            (val & 0x800F00FF);
        openpic_update_irq(opp, n_IRQ);
        DPRINTF("Set IPVP %d to 0x%08x -> 0x%08x\n",
                n_IRQ, val, opp->src[n_IRQ].ipvp);
        break;
    case IRQ_IDE:
        tmp = val & 0xC0000000;
        tmp |= val & ((1 << MAX_CPU) - 1);
        opp->src[n_IRQ].ide = tmp;
        DPRINTF("Set IDE %d to 0x%08x\n", n_IRQ, opp->src[n_IRQ].ide);
        break;
    }
}

#if 0 // Code provision for Intel model
#if MAX_DBL > 0
static uint32_t read_doorbell_register (openpic_t *opp,
                                        int n_dbl, uint32_t offset)
{
    uint32_t retval;

    switch (offset) {
    case DBL_IPVP_OFFSET:
        retval = read_IRQreg(opp, IRQ_DBL0 + n_dbl, IRQ_IPVP);
        break;
    case DBL_IDE_OFFSET:
        retval = read_IRQreg(opp, IRQ_DBL0 + n_dbl, IRQ_IDE);
        break;
    case DBL_DMR_OFFSET:
        retval = opp->doorbells[n_dbl].dmr;
        break;
    }

    return retval;
}

static void write_doorbell_register (penpic_t *opp, int n_dbl,
                                     uint32_t offset, uint32_t value)
{
    switch (offset) {
    case DBL_IVPR_OFFSET:
        write_IRQreg(opp, IRQ_DBL0 + n_dbl, IRQ_IPVP, value);
        break;
    case DBL_IDE_OFFSET:
        write_IRQreg(opp, IRQ_DBL0 + n_dbl, IRQ_IDE, value);
        break;
    case DBL_DMR_OFFSET:
        opp->doorbells[n_dbl].dmr = value;
        break;
    }
}
#endif

#if MAX_MBX > 0
static uint32_t read_mailbox_register (openpic_t *opp,
                                       int n_mbx, uint32_t offset)
{
    uint32_t retval;

    switch (offset) {
    case MBX_MBR_OFFSET:
        retval = opp->mailboxes[n_mbx].mbr;
        break;
    case MBX_IVPR_OFFSET:
        retval = read_IRQreg(opp, IRQ_MBX0 + n_mbx, IRQ_IPVP);
        break;
    case MBX_DMR_OFFSET:
        retval = read_IRQreg(opp, IRQ_MBX0 + n_mbx, IRQ_IDE);
        break;
    }

    return retval;
}

static void write_mailbox_register (openpic_t *opp, int n_mbx,
                                    uint32_t address, uint32_t value)
{
    switch (offset) {
    case MBX_MBR_OFFSET:
        opp->mailboxes[n_mbx].mbr = value;
        break;
    case MBX_IVPR_OFFSET:
        write_IRQreg(opp, IRQ_MBX0 + n_mbx, IRQ_IPVP, value);
        break;
    case MBX_DMR_OFFSET:
        write_IRQreg(opp, IRQ_MBX0 + n_mbx, IRQ_IDE, value);
        break;
    }
}
#endif
#endif /* 0 : Code provision for Intel model */

static void openpic_gbl_write (void *opaque, target_phys_addr_t addr, uint32_t val)
{
    openpic_t *opp = opaque;
    IRQ_dst_t *dst;
    int idx;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;
    addr &= 0xFF;
    switch (addr) {
    case 0x00: /* FREP */
        break;
    case 0x20: /* GLBC */
        if (val & 0x80000000 && opp->reset)
            opp->reset(opp);
        opp->glbc = val & ~0x80000000;
        break;
    case 0x80: /* VENI */
        break;
    case 0x90: /* PINT */
        for (idx = 0; idx < opp->nb_cpus; idx++) {
            if ((val & (1 << idx)) && !(opp->pint & (1 << idx))) {
                DPRINTF("Raise OpenPIC RESET output for CPU %d\n", idx);
                dst = &opp->dst[idx];
                qemu_irq_raise(dst->irqs[OPENPIC_OUTPUT_RESET]);
            } else if (!(val & (1 << idx)) && (opp->pint & (1 << idx))) {
                DPRINTF("Lower OpenPIC RESET output for CPU %d\n", idx);
                dst = &opp->dst[idx];
                qemu_irq_lower(dst->irqs[OPENPIC_OUTPUT_RESET]);
            }
        }
        opp->pint = val;
        break;
#if MAX_IPI > 0
    case 0xA0: /* IPI_IPVP */
    case 0xB0:
    case 0xC0:
    case 0xD0:
        {
            int idx;
            idx = (addr - 0xA0) >> 4;
            write_IRQreg(opp, opp->irq_ipi0 + idx, IRQ_IPVP, val);
        }
        break;
#endif
    case 0xE0: /* SPVE */
        opp->spve = val & 0x000000FF;
        break;
    case 0xF0: /* TIFR */
        opp->tifr = val;
        break;
    default:
        break;
    }
}

static uint32_t openpic_gbl_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *opp = opaque;
    uint32_t retval;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;
    addr &= 0xFF;
    switch (addr) {
    case 0x00: /* FREP */
        retval = opp->frep;
        break;
    case 0x20: /* GLBC */
        retval = opp->glbc;
        break;
    case 0x80: /* VENI */
        retval = opp->veni;
        break;
    case 0x90: /* PINT */
        retval = 0x00000000;
        break;
#if MAX_IPI > 0
    case 0xA0: /* IPI_IPVP */
    case 0xB0:
    case 0xC0:
    case 0xD0:
        {
            int idx;
            idx = (addr - 0xA0) >> 4;
            retval = read_IRQreg(opp, opp->irq_ipi0 + idx, IRQ_IPVP);
        }
        break;
#endif
    case 0xE0: /* SPVE */
        retval = opp->spve;
        break;
    case 0xF0: /* TIFR */
        retval = opp->tifr;
        break;
    default:
        break;
    }
    DPRINTF("%s: => %08x\n", __func__, retval);

    return retval;
}

static void openpic_timer_write (void *opaque, uint32_t addr, uint32_t val)
{
    openpic_t *opp = opaque;
    int idx;

    DPRINTF("%s: addr %08x <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;
    addr -= 0x1100;
    addr &= 0xFFFF;
    idx = (addr & 0xFFF0) >> 6;
    addr = addr & 0x30;
    switch (addr) {
    case 0x00: /* TICC */
        break;
    case 0x10: /* TIBC */
        if ((opp->timers[idx].ticc & 0x80000000) != 0 &&
            (val & 0x80000000) == 0 &&
            (opp->timers[idx].tibc & 0x80000000) != 0)
            opp->timers[idx].ticc &= ~0x80000000;
        opp->timers[idx].tibc = val;
        break;
    case 0x20: /* TIVP */
        write_IRQreg(opp, opp->irq_tim0 + idx, IRQ_IPVP, val);
        break;
    case 0x30: /* TIDE */
        write_IRQreg(opp, opp->irq_tim0 + idx, IRQ_IDE, val);
        break;
    }
}

static uint32_t openpic_timer_read (void *opaque, uint32_t addr)
{
    openpic_t *opp = opaque;
    uint32_t retval;
    int idx;

    DPRINTF("%s: addr %08x\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;
    addr -= 0x1100;
    addr &= 0xFFFF;
    idx = (addr & 0xFFF0) >> 6;
    addr = addr & 0x30;
    switch (addr) {
    case 0x00: /* TICC */
        retval = opp->timers[idx].ticc;
        break;
    case 0x10: /* TIBC */
        retval = opp->timers[idx].tibc;
        break;
    case 0x20: /* TIPV */
        retval = read_IRQreg(opp, opp->irq_tim0 + idx, IRQ_IPVP);
        break;
    case 0x30: /* TIDE */
        retval = read_IRQreg(opp, opp->irq_tim0 + idx, IRQ_IDE);
        break;
    }
    DPRINTF("%s: => %08x\n", __func__, retval);

    return retval;
}

static void openpic_src_write (void *opaque, uint32_t addr, uint32_t val)
{
    openpic_t *opp = opaque;
    int idx;

    DPRINTF("%s: addr %08x <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;
    addr = addr & 0xFFF0;
    idx = addr >> 5;
    if (addr & 0x10) {
        /* EXDE / IFEDE / IEEDE */
        write_IRQreg(opp, idx, IRQ_IDE, val);
    } else {
        /* EXVP / IFEVP / IEEVP */
        write_IRQreg(opp, idx, IRQ_IPVP, val);
    }
}

static uint32_t openpic_src_read (void *opaque, uint32_t addr)
{
    openpic_t *opp = opaque;
    uint32_t retval;
    int idx;

    DPRINTF("%s: addr %08x\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;
    addr = addr & 0xFFF0;
    idx = addr >> 5;
    if (addr & 0x10) {
        /* EXDE / IFEDE / IEEDE */
        retval = read_IRQreg(opp, idx, IRQ_IDE);
    } else {
        /* EXVP / IFEVP / IEEVP */
        retval = read_IRQreg(opp, idx, IRQ_IPVP);
    }
    DPRINTF("%s: => %08x\n", __func__, retval);

    return retval;
}

static void openpic_cpu_write (void *opaque, target_phys_addr_t addr, uint32_t val)
{
    openpic_t *opp = opaque;
    IRQ_src_t *src;
    IRQ_dst_t *dst;
    int idx, s_IRQ, n_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;
    addr &= 0x1FFF0;
    idx = addr / 0x1000;
    dst = &opp->dst[idx];
    addr &= 0xFF0;
    switch (addr) {
#if MAX_IPI > 0
    case 0x40: /* PIPD */
    case 0x50:
    case 0x60:
    case 0x70:
        idx = (addr - 0x40) >> 4;
        write_IRQreg(opp, opp->irq_ipi0 + idx, IRQ_IDE, val);
        openpic_set_irq(opp, opp->irq_ipi0 + idx, 1);
        openpic_set_irq(opp, opp->irq_ipi0 + idx, 0);
        break;
#endif
    case 0x80: /* PCTP */
        dst->pctp = val & 0x0000000F;
        break;
    case 0x90: /* WHOAMI */
        /* Read-only register */
        break;
    case 0xA0: /* PIAC */
        /* Read-only register */
        break;
    case 0xB0: /* PEOI */
        DPRINTF("PEOI\n");
        s_IRQ = IRQ_get_next(opp, &dst->servicing);
        IRQ_resetbit(&dst->servicing, s_IRQ);
        dst->servicing.next = -1;
        /* Set up next servicing IRQ */
        s_IRQ = IRQ_get_next(opp, &dst->servicing);
        /* Check queued interrupts. */
        n_IRQ = IRQ_get_next(opp, &dst->raised);
        src = &opp->src[n_IRQ];
        if (n_IRQ != -1 &&
            (s_IRQ == -1 ||
             IPVP_PRIORITY(src->ipvp) > dst->servicing.priority)) {
            DPRINTF("Raise OpenPIC INT output cpu %d irq %d\n",
                    idx, n_IRQ);
            opp->irq_raise(opp, idx, src);
        }
        break;
    default:
        break;
    }
}

static uint32_t openpic_cpu_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *opp = opaque;
    IRQ_src_t *src;
    IRQ_dst_t *dst;
    uint32_t retval;
    int idx, n_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;
    addr &= 0x1FFF0;
    idx = addr / 0x1000;
    dst = &opp->dst[idx];
    addr &= 0xFF0;
    switch (addr) {
    case 0x80: /* PCTP */
        retval = dst->pctp;
        break;
    case 0x90: /* WHOAMI */
        retval = idx;
        break;
    case 0xA0: /* PIAC */
        DPRINTF("Lower OpenPIC INT output\n");
        qemu_irq_lower(dst->irqs[OPENPIC_OUTPUT_INT]);
        n_IRQ = IRQ_get_next(opp, &dst->raised);
        DPRINTF("PIAC: irq=%d\n", n_IRQ);
        if (n_IRQ == -1) {
            /* No more interrupt pending */
            retval = IPVP_VECTOR(opp->spve);
        } else {
            src = &opp->src[n_IRQ];
            if (!test_bit(&src->ipvp, IPVP_ACTIVITY) ||
                !(IPVP_PRIORITY(src->ipvp) > dst->pctp)) {
                /* - Spurious level-sensitive IRQ
                 * - Priorities has been changed
                 *   and the pending IRQ isn't allowed anymore
                 */
                reset_bit(&src->ipvp, IPVP_ACTIVITY);
                retval = IPVP_VECTOR(opp->spve);
            } else {
                /* IRQ enter servicing state */
                IRQ_setbit(&dst->servicing, n_IRQ);
                retval = IPVP_VECTOR(src->ipvp);
            }
            IRQ_resetbit(&dst->raised, n_IRQ);
            dst->raised.next = -1;
            if (!test_bit(&src->ipvp, IPVP_SENSE)) {
                /* edge-sensitive IRQ */
                reset_bit(&src->ipvp, IPVP_ACTIVITY);
                src->pending = 0;
            }
        }
        break;
    case 0xB0: /* PEOI */
        retval = 0;
        break;
#if MAX_IPI > 0
    case 0x40: /* IDE */
    case 0x50:
        idx = (addr - 0x40) >> 4;
        retval = read_IRQreg(opp, opp->irq_ipi0 + idx, IRQ_IDE);
        break;
#endif
    default:
        break;
    }
    DPRINTF("%s: => %08x\n", __func__, retval);

    return retval;
}

static void openpic_buggy_write (void *opaque,
                                 target_phys_addr_t addr, uint32_t val)
{
    printf("Invalid OPENPIC write access !\n");
}

static uint32_t openpic_buggy_read (void *opaque, target_phys_addr_t addr)
{
    printf("Invalid OPENPIC read access !\n");

    return -1;
}

static void openpic_writel (void *opaque,
                            target_phys_addr_t addr, uint32_t val)
{
    openpic_t *opp = opaque;

    addr &= 0x3FFFF;
    DPRINTF("%s: offset %08x val: %08x\n", __func__, (int)addr, val);
    if (addr < 0x1100) {
        /* Global registers */
        openpic_gbl_write(opp, addr, val);
    } else if (addr < 0x10000) {
        /* Timers registers */
        openpic_timer_write(opp, addr, val);
    } else if (addr < 0x20000) {
        /* Source registers */
        openpic_src_write(opp, addr, val);
    } else {
        /* CPU registers */
        openpic_cpu_write(opp, addr, val);
    }
}

static uint32_t openpic_readl (void *opaque,target_phys_addr_t addr)
{
    openpic_t *opp = opaque;
    uint32_t retval;

    addr &= 0x3FFFF;
    DPRINTF("%s: offset %08x\n", __func__, (int)addr);
    if (addr < 0x1100) {
        /* Global registers */
        retval = openpic_gbl_read(opp, addr);
    } else if (addr < 0x10000) {
        /* Timers registers */
        retval = openpic_timer_read(opp, addr);
    } else if (addr < 0x20000) {
        /* Source registers */
        retval = openpic_src_read(opp, addr);
    } else {
        /* CPU registers */
        retval = openpic_cpu_read(opp, addr);
    }

    return retval;
}

static CPUWriteMemoryFunc * const openpic_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &openpic_writel,
};

static CPUReadMemoryFunc * const openpic_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &openpic_readl,
};

static void openpic_map(PCIDevice *pci_dev, int region_num,
                        pcibus_t addr, pcibus_t size, int type)
{
    openpic_t *opp;

    DPRINTF("Map OpenPIC\n");
    opp = (openpic_t *)pci_dev;
    /* Global registers */
    DPRINTF("Register OPENPIC gbl   %08x => %08x\n",
            addr + 0x1000, addr + 0x1000 + 0x100);
    /* Timer registers */
    DPRINTF("Register OPENPIC timer %08x => %08x\n",
            addr + 0x1100, addr + 0x1100 + 0x40 * MAX_TMR);
    /* Interrupt source registers */
    DPRINTF("Register OPENPIC src   %08x => %08x\n",
            addr + 0x10000, addr + 0x10000 + 0x20 * (OPENPIC_EXT_IRQ + 2));
    /* Per CPU registers */
    DPRINTF("Register OPENPIC dst   %08x => %08x\n",
            addr + 0x20000, addr + 0x20000 + 0x1000 * MAX_CPU);
    cpu_register_physical_memory(addr, 0x40000, opp->mem_index);
#if 0 // Don't implement ISU for now
    opp_io_memory = cpu_register_io_memory(openpic_src_read,
                                           openpic_src_write, NULL
                                           DEVICE_NATIVE_ENDIAN);
    cpu_register_physical_memory(isu_base, 0x20 * (EXT_IRQ + 2),
                                 opp_io_memory);
#endif
}

static void openpic_save_IRQ_queue(QEMUFile* f, IRQ_queue_t *q)
{
    unsigned int i;

    for (i = 0; i < BF_WIDTH(MAX_IRQ); i++)
        qemu_put_be32s(f, &q->queue[i]);

    qemu_put_sbe32s(f, &q->next);
    qemu_put_sbe32s(f, &q->priority);
}

static void openpic_save(QEMUFile* f, void *opaque)
{
    openpic_t *opp = (openpic_t *)opaque;
    unsigned int i;

    qemu_put_be32s(f, &opp->frep);
    qemu_put_be32s(f, &opp->glbc);
    qemu_put_be32s(f, &opp->micr);
    qemu_put_be32s(f, &opp->veni);
    qemu_put_be32s(f, &opp->pint);
    qemu_put_be32s(f, &opp->spve);
    qemu_put_be32s(f, &opp->tifr);

    for (i = 0; i < opp->max_irq; i++) {
        qemu_put_be32s(f, &opp->src[i].ipvp);
        qemu_put_be32s(f, &opp->src[i].ide);
        qemu_put_sbe32s(f, &opp->src[i].type);
        qemu_put_sbe32s(f, &opp->src[i].last_cpu);
        qemu_put_sbe32s(f, &opp->src[i].pending);
    }

    qemu_put_sbe32s(f, &opp->nb_cpus);

    for (i = 0; i < opp->nb_cpus; i++) {
        qemu_put_be32s(f, &opp->dst[i].tfrr);
        qemu_put_be32s(f, &opp->dst[i].pctp);
        qemu_put_be32s(f, &opp->dst[i].pcsr);
        openpic_save_IRQ_queue(f, &opp->dst[i].raised);
        openpic_save_IRQ_queue(f, &opp->dst[i].servicing);
    }

    for (i = 0; i < MAX_TMR; i++) {
        qemu_put_be32s(f, &opp->timers[i].ticc);
        qemu_put_be32s(f, &opp->timers[i].tibc);
    }

#if MAX_DBL > 0
    qemu_put_be32s(f, &opp->dar);

    for (i = 0; i < MAX_DBL; i++) {
        qemu_put_be32s(f, &opp->doorbells[i].dmr);
    }
#endif

#if MAX_MBX > 0
    for (i = 0; i < MAX_MAILBOXES; i++) {
        qemu_put_be32s(f, &opp->mailboxes[i].mbr);
    }
#endif

    pci_device_save(&opp->pci_dev, f);
}

static void openpic_load_IRQ_queue(QEMUFile* f, IRQ_queue_t *q)
{
    unsigned int i;

    for (i = 0; i < BF_WIDTH(MAX_IRQ); i++)
        qemu_get_be32s(f, &q->queue[i]);

    qemu_get_sbe32s(f, &q->next);
    qemu_get_sbe32s(f, &q->priority);
}

static int openpic_load(QEMUFile* f, void *opaque, int version_id)
{
    openpic_t *opp = (openpic_t *)opaque;
    unsigned int i;

    if (version_id != 1)
        return -EINVAL;

    qemu_get_be32s(f, &opp->frep);
    qemu_get_be32s(f, &opp->glbc);
    qemu_get_be32s(f, &opp->micr);
    qemu_get_be32s(f, &opp->veni);
    qemu_get_be32s(f, &opp->pint);
    qemu_get_be32s(f, &opp->spve);
    qemu_get_be32s(f, &opp->tifr);

    for (i = 0; i < opp->max_irq; i++) {
        qemu_get_be32s(f, &opp->src[i].ipvp);
        qemu_get_be32s(f, &opp->src[i].ide);
        qemu_get_sbe32s(f, &opp->src[i].type);
        qemu_get_sbe32s(f, &opp->src[i].last_cpu);
        qemu_get_sbe32s(f, &opp->src[i].pending);
    }

    qemu_get_sbe32s(f, &opp->nb_cpus);

    for (i = 0; i < opp->nb_cpus; i++) {
        qemu_get_be32s(f, &opp->dst[i].tfrr);
        qemu_get_be32s(f, &opp->dst[i].pctp);
        qemu_get_be32s(f, &opp->dst[i].pcsr);
        openpic_load_IRQ_queue(f, &opp->dst[i].raised);
        openpic_load_IRQ_queue(f, &opp->dst[i].servicing);
    }

    for (i = 0; i < MAX_TMR; i++) {
        qemu_get_be32s(f, &opp->timers[i].ticc);
        qemu_get_be32s(f, &opp->timers[i].tibc);
    }

#if MAX_DBL > 0
    qemu_get_be32s(f, &opp->dar);

    for (i = 0; i < MAX_DBL; i++) {
        qemu_get_be32s(f, &opp->doorbells[i].dmr);
    }
#endif

#if MAX_MBX > 0
    for (i = 0; i < MAX_MAILBOXES; i++) {
        qemu_get_be32s(f, &opp->mailboxes[i].mbr);
    }
#endif

    return pci_device_load(&opp->pci_dev, f);
}

static void openpic_irq_raise(openpic_t *opp, int n_CPU, IRQ_src_t *src)
{
    qemu_irq_raise(opp->dst[n_CPU].irqs[OPENPIC_OUTPUT_INT]);
}

qemu_irq *openpic_init (PCIBus *bus, int *pmem_index, int nb_cpus,
                        qemu_irq **irqs, qemu_irq irq_out)
{
    openpic_t *opp;
    uint8_t *pci_conf;
    int i, m;

    /* XXX: for now, only one CPU is supported */
    if (nb_cpus != 1)
        return NULL;
    if (bus) {
        opp = (openpic_t *)pci_register_device(bus, "OpenPIC", sizeof(openpic_t),
                                               -1, NULL, NULL);
        pci_conf = opp->pci_dev.config;
        pci_config_set_vendor_id(pci_conf, PCI_VENDOR_ID_IBM);
        pci_config_set_device_id(pci_conf, PCI_DEVICE_ID_IBM_OPENPIC2);
        pci_config_set_class(pci_conf, PCI_CLASS_SYSTEM_OTHER); // FIXME?
        pci_conf[0x3d] = 0x00; // no interrupt pin

        /* Register I/O spaces */
        pci_register_bar(&opp->pci_dev, 0, 0x40000,
                               PCI_BASE_ADDRESS_SPACE_MEMORY, &openpic_map);
    } else {
        opp = qemu_mallocz(sizeof(openpic_t));
    }
    opp->mem_index = cpu_register_io_memory(openpic_read, openpic_write, opp,
                                            DEVICE_LITTLE_ENDIAN);

    //    isu_base &= 0xFFFC0000;
    opp->nb_cpus = nb_cpus;
    opp->max_irq = OPENPIC_MAX_IRQ;
    opp->irq_ipi0 = OPENPIC_IRQ_IPI0;
    opp->irq_tim0 = OPENPIC_IRQ_TIM0;
    /* Set IRQ types */
    for (i = 0; i < OPENPIC_EXT_IRQ; i++) {
        opp->src[i].type = IRQ_EXTERNAL;
    }
    for (; i < OPENPIC_IRQ_TIM0; i++) {
        opp->src[i].type = IRQ_SPECIAL;
    }
#if MAX_IPI > 0
    m = OPENPIC_IRQ_IPI0;
#else
    m = OPENPIC_IRQ_DBL0;
#endif
    for (; i < m; i++) {
        opp->src[i].type = IRQ_TIMER;
    }
    for (; i < OPENPIC_MAX_IRQ; i++) {
        opp->src[i].type = IRQ_INTERNAL;
    }
    for (i = 0; i < nb_cpus; i++)
        opp->dst[i].irqs = irqs[i];
    opp->irq_out = irq_out;

    register_savevm(&opp->pci_dev.qdev, "openpic", 0, 2,
                    openpic_save, openpic_load, opp);
    qemu_register_reset(openpic_reset, opp);

    opp->irq_raise = openpic_irq_raise;
    opp->reset = openpic_reset;

    if (pmem_index)
        *pmem_index = opp->mem_index;

    return qemu_allocate_irqs(openpic_set_irq, opp, opp->max_irq);
}

static void mpic_irq_raise(openpic_t *mpp, int n_CPU, IRQ_src_t *src)
{
    int n_ci = IDR_CI0 - n_CPU;

    if(test_bit(&src->ide, n_ci)) {
        qemu_irq_raise(mpp->dst[n_CPU].irqs[OPENPIC_OUTPUT_CINT]);
    }
    else {
        qemu_irq_raise(mpp->dst[n_CPU].irqs[OPENPIC_OUTPUT_INT]);
    }
}

static void mpic_reset (void *opaque)
{
    openpic_t *mpp = (openpic_t *)opaque;
    int i;

    mpp->glbc = 0x80000000;
    /* Initialise controller registers */
    mpp->frep = 0x004f0002;
    mpp->veni = VENI;
    mpp->pint = 0x00000000;
    mpp->spve = 0x0000FFFF;
    /* Initialise IRQ sources */
    for (i = 0; i < mpp->max_irq; i++) {
        mpp->src[i].ipvp = 0x80800000;
        mpp->src[i].ide  = 0x00000001;
    }
    /* Initialise IRQ destinations */
    for (i = 0; i < MAX_CPU; i++) {
        mpp->dst[i].pctp      = 0x0000000F;
        mpp->dst[i].tfrr      = 0x00000000;
        memset(&mpp->dst[i].raised, 0, sizeof(IRQ_queue_t));
        mpp->dst[i].raised.next = -1;
        memset(&mpp->dst[i].servicing, 0, sizeof(IRQ_queue_t));
        mpp->dst[i].servicing.next = -1;
    }
    /* Initialise timers */
    for (i = 0; i < MAX_TMR; i++) {
        mpp->timers[i].ticc = 0x00000000;
        mpp->timers[i].tibc = 0x80000000;
    }
    /* Go out of RESET state */
    mpp->glbc = 0x00000000;
}

static void mpic_timer_write (void *opaque, target_phys_addr_t addr, uint32_t val)
{
    openpic_t *mpp = opaque;
    int idx, cpu;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;
    addr &= 0xFFFF;
    cpu = addr >> 12;
    idx = (addr >> 6) & 0x3;
    switch (addr & 0x30) {
    case 0x00: /* gtccr */
        break;
    case 0x10: /* gtbcr */
        if ((mpp->timers[idx].ticc & 0x80000000) != 0 &&
            (val & 0x80000000) == 0 &&
            (mpp->timers[idx].tibc & 0x80000000) != 0)
            mpp->timers[idx].ticc &= ~0x80000000;
        mpp->timers[idx].tibc = val;
        break;
    case 0x20: /* GTIVPR */
        write_IRQreg(mpp, MPIC_TMR_IRQ + idx, IRQ_IPVP, val);
        break;
    case 0x30: /* GTIDR & TFRR */
        if ((addr & 0xF0) == 0xF0)
            mpp->dst[cpu].tfrr = val;
        else
            write_IRQreg(mpp, MPIC_TMR_IRQ + idx, IRQ_IDE, val);
        break;
    }
}

static uint32_t mpic_timer_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *mpp = opaque;
    uint32_t retval;
    int idx, cpu;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;
    addr &= 0xFFFF;
    cpu = addr >> 12;
    idx = (addr >> 6) & 0x3;
    switch (addr & 0x30) {
    case 0x00: /* gtccr */
        retval = mpp->timers[idx].ticc;
        break;
    case 0x10: /* gtbcr */
        retval = mpp->timers[idx].tibc;
        break;
    case 0x20: /* TIPV */
        retval = read_IRQreg(mpp, MPIC_TMR_IRQ + idx, IRQ_IPVP);
        break;
    case 0x30: /* TIDR */
        if ((addr &0xF0) == 0XF0)
            retval = mpp->dst[cpu].tfrr;
        else
            retval = read_IRQreg(mpp, MPIC_TMR_IRQ + idx, IRQ_IDE);
        break;
    }
    DPRINTF("%s: => %08x\n", __func__, retval);

    return retval;
}

static void mpic_src_ext_write (void *opaque, target_phys_addr_t addr,
                                uint32_t val)
{
    openpic_t *mpp = opaque;
    int idx = MPIC_EXT_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;

    addr -= MPIC_EXT_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_EXT_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            write_IRQreg(mpp, idx, IRQ_IDE, val);
        } else {
            /* EXVP / IFEVP / IEEVP */
            write_IRQreg(mpp, idx, IRQ_IPVP, val);
        }
    }
}

static uint32_t mpic_src_ext_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *mpp = opaque;
    uint32_t retval;
    int idx = MPIC_EXT_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;

    addr -= MPIC_EXT_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_EXT_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            retval = read_IRQreg(mpp, idx, IRQ_IDE);
        } else {
            /* EXVP / IFEVP / IEEVP */
            retval = read_IRQreg(mpp, idx, IRQ_IPVP);
        }
        DPRINTF("%s: => %08x\n", __func__, retval);
    }

    return retval;
}

static void mpic_src_int_write (void *opaque, target_phys_addr_t addr,
                                uint32_t val)
{
    openpic_t *mpp = opaque;
    int idx = MPIC_INT_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;

    addr -= MPIC_INT_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_INT_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            write_IRQreg(mpp, idx, IRQ_IDE, val);
        } else {
            /* EXVP / IFEVP / IEEVP */
            write_IRQreg(mpp, idx, IRQ_IPVP, val);
        }
    }
}

static uint32_t mpic_src_int_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *mpp = opaque;
    uint32_t retval;
    int idx = MPIC_INT_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;

    addr -= MPIC_INT_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_INT_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            retval = read_IRQreg(mpp, idx, IRQ_IDE);
        } else {
            /* EXVP / IFEVP / IEEVP */
            retval = read_IRQreg(mpp, idx, IRQ_IPVP);
        }
        DPRINTF("%s: => %08x\n", __func__, retval);
    }

    return retval;
}

static void mpic_src_msg_write (void *opaque, target_phys_addr_t addr,
                                uint32_t val)
{
    openpic_t *mpp = opaque;
    int idx = MPIC_MSG_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;

    addr -= MPIC_MSG_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_MSG_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            write_IRQreg(mpp, idx, IRQ_IDE, val);
        } else {
            /* EXVP / IFEVP / IEEVP */
            write_IRQreg(mpp, idx, IRQ_IPVP, val);
        }
    }
}

static uint32_t mpic_src_msg_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *mpp = opaque;
    uint32_t retval;
    int idx = MPIC_MSG_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;

    addr -= MPIC_MSG_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_MSG_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            retval = read_IRQreg(mpp, idx, IRQ_IDE);
        } else {
            /* EXVP / IFEVP / IEEVP */
            retval = read_IRQreg(mpp, idx, IRQ_IPVP);
        }
        DPRINTF("%s: => %08x\n", __func__, retval);
    }

    return retval;
}

static void mpic_src_msi_write (void *opaque, target_phys_addr_t addr,
                                uint32_t val)
{
    openpic_t *mpp = opaque;
    int idx = MPIC_MSI_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx " <= %08x\n", __func__, addr, val);
    if (addr & 0xF)
        return;

    addr -= MPIC_MSI_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_MSI_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            write_IRQreg(mpp, idx, IRQ_IDE, val);
        } else {
            /* EXVP / IFEVP / IEEVP */
            write_IRQreg(mpp, idx, IRQ_IPVP, val);
        }
    }
}
static uint32_t mpic_src_msi_read (void *opaque, target_phys_addr_t addr)
{
    openpic_t *mpp = opaque;
    uint32_t retval;
    int idx = MPIC_MSI_IRQ;

    DPRINTF("%s: addr " TARGET_FMT_plx "\n", __func__, addr);
    retval = 0xFFFFFFFF;
    if (addr & 0xF)
        return retval;

    addr -= MPIC_MSI_REG_START & (OPENPIC_PAGE_SIZE - 1);
    if (addr < MPIC_MSI_REG_SIZE) {
        idx += (addr & 0xFFF0) >> 5;
        if (addr & 0x10) {
            /* EXDE / IFEDE / IEEDE */
            retval = read_IRQreg(mpp, idx, IRQ_IDE);
        } else {
            /* EXVP / IFEVP / IEEVP */
            retval = read_IRQreg(mpp, idx, IRQ_IPVP);
        }
        DPRINTF("%s: => %08x\n", __func__, retval);
    }

    return retval;
}

static CPUWriteMemoryFunc * const mpic_glb_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &openpic_gbl_write,
};

static CPUReadMemoryFunc * const mpic_glb_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &openpic_gbl_read,
};

static CPUWriteMemoryFunc * const mpic_tmr_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &mpic_timer_write,
};

static CPUReadMemoryFunc * const mpic_tmr_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &mpic_timer_read,
};

static CPUWriteMemoryFunc * const mpic_cpu_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &openpic_cpu_write,
};

static CPUReadMemoryFunc * const mpic_cpu_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &openpic_cpu_read,
};

static CPUWriteMemoryFunc * const mpic_ext_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &mpic_src_ext_write,
};

static CPUReadMemoryFunc * const mpic_ext_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &mpic_src_ext_read,
};

static CPUWriteMemoryFunc * const mpic_int_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &mpic_src_int_write,
};

static CPUReadMemoryFunc * const mpic_int_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &mpic_src_int_read,
};

static CPUWriteMemoryFunc * const mpic_msg_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &mpic_src_msg_write,
};

static CPUReadMemoryFunc * const mpic_msg_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &mpic_src_msg_read,
};
static CPUWriteMemoryFunc * const mpic_msi_write[] = {
    &openpic_buggy_write,
    &openpic_buggy_write,
    &mpic_src_msi_write,
};

static CPUReadMemoryFunc * const mpic_msi_read[] = {
    &openpic_buggy_read,
    &openpic_buggy_read,
    &mpic_src_msi_read,
};

qemu_irq *mpic_init (target_phys_addr_t base, int nb_cpus,
                        qemu_irq **irqs, qemu_irq irq_out)
{
    openpic_t *mpp;
    int i;
    struct {
        CPUReadMemoryFunc * const *read;
        CPUWriteMemoryFunc * const *write;
        target_phys_addr_t start_addr;
        ram_addr_t size;
    } const list[] = {
        {mpic_glb_read, mpic_glb_write, MPIC_GLB_REG_START, MPIC_GLB_REG_SIZE},
        {mpic_tmr_read, mpic_tmr_write, MPIC_TMR_REG_START, MPIC_TMR_REG_SIZE},
        {mpic_ext_read, mpic_ext_write, MPIC_EXT_REG_START, MPIC_EXT_REG_SIZE},
        {mpic_int_read, mpic_int_write, MPIC_INT_REG_START, MPIC_INT_REG_SIZE},
        {mpic_msg_read, mpic_msg_write, MPIC_MSG_REG_START, MPIC_MSG_REG_SIZE},
        {mpic_msi_read, mpic_msi_write, MPIC_MSI_REG_START, MPIC_MSI_REG_SIZE},
        {mpic_cpu_read, mpic_cpu_write, MPIC_CPU_REG_START, MPIC_CPU_REG_SIZE},
    };

    /* XXX: for now, only one CPU is supported */
    if (nb_cpus != 1)
        return NULL;

    mpp = qemu_mallocz(sizeof(openpic_t));

    for (i = 0; i < sizeof(list)/sizeof(list[0]); i++) {
        int mem_index;

        mem_index = cpu_register_io_memory(list[i].read, list[i].write, mpp,
                                           DEVICE_BIG_ENDIAN);
        if (mem_index < 0) {
            goto free;
        }
        cpu_register_physical_memory(base + list[i].start_addr,
                                     list[i].size, mem_index);
    }

    mpp->nb_cpus = nb_cpus;
    mpp->max_irq = MPIC_MAX_IRQ;
    mpp->irq_ipi0 = MPIC_IPI_IRQ;
    mpp->irq_tim0 = MPIC_TMR_IRQ;

    for (i = 0; i < nb_cpus; i++)
        mpp->dst[i].irqs = irqs[i];
    mpp->irq_out = irq_out;

    mpp->irq_raise = mpic_irq_raise;
    mpp->reset = mpic_reset;

    register_savevm(NULL, "mpic", 0, 2, openpic_save, openpic_load, mpp);
    qemu_register_reset(mpic_reset, mpp);

    return qemu_allocate_irqs(openpic_set_irq, mpp, mpp->max_irq);

free:
    qemu_free(mpp);
    return NULL;
}