Archipelago » qemu

/*

 * QEMU PPC PREP hardware System Emulator

 *

 * Copyright (c) 2003-2007 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.

 */

#include "hw.h"

#include "nvram.h"

#include "pc.h"

#include "fdc.h"

#include "net.h"

#include "sysemu.h"

#include "isa.h"

#include "pci.h"

#include "ppc.h"

#include "boards.h"

//#define HARD_DEBUG_PPC_IO

//#define DEBUG_PPC_IO

/* SMP is not enabled, for now */

#define MAX_CPUS 1

#define BIOS_FILENAME "ppc_rom.bin"

#define KERNEL_LOAD_ADDR 0x01000000

#define INITRD_LOAD_ADDR 0x01800000

extern int loglevel;

extern FILE *logfile;

#if defined (HARD_DEBUG_PPC_IO) && !defined (DEBUG_PPC_IO)

#define DEBUG_PPC_IO

#endif

#if defined (HARD_DEBUG_PPC_IO)

#define PPC_IO_DPRINTF(fmt, args...)                     \

do {                                                     \

    if (loglevel & CPU_LOG_IOPORT) {                     \

        fprintf(logfile, "%s: " fmt, __func__ , ##args); \

    } else {                                             \

        printf("%s : " fmt, __func__ , ##args);          \

    }                                                    \

} while (0)

#elif defined (DEBUG_PPC_IO)

#define PPC_IO_DPRINTF(fmt, args...)                     \

do {                                                     \

    if (loglevel & CPU_LOG_IOPORT) {                     \

        fprintf(logfile, "%s: " fmt, __func__ , ##args); \

    }                                                    \

} while (0)

#else

#define PPC_IO_DPRINTF(fmt, args...) do { } while (0)

#endif

/* Constants for devices init */

static const int ide_iobase[2] = { 0x1f0, 0x170 };

static const int ide_iobase2[2] = { 0x3f6, 0x376 };

static const int ide_irq[2] = { 13, 13 };

#define NE2000_NB_MAX 6

static uint32_t ne2000_io[NE2000_NB_MAX] = { 0x300, 0x320, 0x340, 0x360, 0x280, 0x380 };

static int ne2000_irq[NE2000_NB_MAX] = { 9, 10, 11, 3, 4, 5 };

//static PITState *pit;

/* ISA IO ports bridge */

#define PPC_IO_BASE 0x80000000

/* Speaker port 0x61 */

int speaker_data_on;

int dummy_refresh_clock;

static void speaker_ioport_write (void *opaque, uint32_t addr, uint32_t val)

{

#if 0

    speaker_data_on = (val >> 1) & 1;

    pit_set_gate(pit, 2, val & 1);

#endif

}

static uint32_t speaker_ioport_read (void *opaque, uint32_t addr)

{

#if 0

    int out;

    out = pit_get_out(pit, 2, qemu_get_clock(vm_clock));

    dummy_refresh_clock ^= 1;

    return (speaker_data_on << 1) | pit_get_gate(pit, 2) | (out << 5) |

        (dummy_refresh_clock << 4);

#endif

    return 0;

}

/* PCI intack register */

/* Read-only register (?) */

static void _PPC_intack_write (void *opaque,

                               target_phys_addr_t addr, uint32_t value)

{

    //    printf("%s: 0x%08x => 0x%08x\n", __func__, addr, value);

}

static always_inline uint32_t _PPC_intack_read (target_phys_addr_t addr)

{

    uint32_t retval = 0;

    if (addr == 0xBFFFFFF0)

        retval = pic_intack_read(isa_pic);

    //   printf("%s: 0x%08x <= %d\n", __func__, addr, retval);

    return retval;

}

static uint32_t PPC_intack_readb (void *opaque, target_phys_addr_t addr)

{

    return _PPC_intack_read(addr);

}

static uint32_t PPC_intack_readw (void *opaque, target_phys_addr_t addr)

{

#ifdef TARGET_WORDS_BIGENDIAN

    return bswap16(_PPC_intack_read(addr));

#else

    return _PPC_intack_read(addr);

#endif

}

static uint32_t PPC_intack_readl (void *opaque, target_phys_addr_t addr)

{

#ifdef TARGET_WORDS_BIGENDIAN

    return bswap32(_PPC_intack_read(addr));

#else

    return _PPC_intack_read(addr);

#endif

}

static CPUWriteMemoryFunc *PPC_intack_write[] = {

    &_PPC_intack_write,

    &_PPC_intack_write,

    &_PPC_intack_write,

};

static CPUReadMemoryFunc *PPC_intack_read[] = {

    &PPC_intack_readb,

    &PPC_intack_readw,

    &PPC_intack_readl,

};

/* PowerPC control and status registers */

#if 0 // Not used

static struct {

    /* IDs */

    uint32_t veni_devi;

    uint32_t revi;

    /* Control and status */

    uint32_t gcsr;

    uint32_t xcfr;

    uint32_t ct32;

    uint32_t mcsr;

    /* General purpose registers */

    uint32_t gprg[6];

    /* Exceptions */

    uint32_t feen;

    uint32_t fest;

    uint32_t fema;

    uint32_t fecl;

    uint32_t eeen;

    uint32_t eest;

    uint32_t eecl;

    uint32_t eeint;

    uint32_t eemck0;

    uint32_t eemck1;

    /* Error diagnostic */

} XCSR;

static void PPC_XCSR_writeb (void *opaque,

                             target_phys_addr_t addr, uint32_t value)

{

    printf("%s: 0x%08lx => 0x%08x\n", __func__, (long)addr, value);

}

static void PPC_XCSR_writew (void *opaque,

                             target_phys_addr_t addr, uint32_t value)

{

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap16(value);

#endif

    printf("%s: 0x%08lx => 0x%08x\n", __func__, (long)addr, value);

}

static void PPC_XCSR_writel (void *opaque,

                             target_phys_addr_t addr, uint32_t value)

{

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap32(value);

#endif

    printf("%s: 0x%08lx => 0x%08x\n", __func__, (long)addr, value);

}

static uint32_t PPC_XCSR_readb (void *opaque, target_phys_addr_t addr)

{

    uint32_t retval = 0;

    printf("%s: 0x%08lx <= %d\n", __func__, (long)addr, retval);

    return retval;

}

static uint32_t PPC_XCSR_readw (void *opaque, target_phys_addr_t addr)

{

    uint32_t retval = 0;

    printf("%s: 0x%08lx <= %d\n", __func__, (long)addr, retval);

#ifdef TARGET_WORDS_BIGENDIAN

    retval = bswap16(retval);

#endif

    return retval;

}

static uint32_t PPC_XCSR_readl (void *opaque, target_phys_addr_t addr)

{

    uint32_t retval = 0;

    printf("%s: 0x%08lx <= %d\n", __func__, (long)addr, retval);

#ifdef TARGET_WORDS_BIGENDIAN

    retval = bswap32(retval);

#endif

    return retval;

}

static CPUWriteMemoryFunc *PPC_XCSR_write[] = {

    &PPC_XCSR_writeb,

    &PPC_XCSR_writew,

    &PPC_XCSR_writel,

};

static CPUReadMemoryFunc *PPC_XCSR_read[] = {

    &PPC_XCSR_readb,

    &PPC_XCSR_readw,

    &PPC_XCSR_readl,

};

#endif

/* Fake super-io ports for PREP platform (Intel 82378ZB) */

typedef struct sysctrl_t {

    qemu_irq reset_irq;

    m48t59_t *nvram;

    uint8_t state;

    uint8_t syscontrol;

    uint8_t fake_io[2];

    int contiguous_map;

    int endian;

} sysctrl_t;

enum {

    STATE_HARDFILE = 0x01,

};

static sysctrl_t *sysctrl;

static void PREP_io_write (void *opaque, uint32_t addr, uint32_t val)

{

    sysctrl_t *sysctrl = opaque;

    PPC_IO_DPRINTF("0x%08lx => 0x%08x\n", (long)addr - PPC_IO_BASE, val);

    sysctrl->fake_io[addr - 0x0398] = val;

}

static uint32_t PREP_io_read (void *opaque, uint32_t addr)

{

    sysctrl_t *sysctrl = opaque;

    PPC_IO_DPRINTF("0x%08lx <= 0x%08x\n", (long)addr - PPC_IO_BASE,

                   sysctrl->fake_io[addr - 0x0398]);

    return sysctrl->fake_io[addr - 0x0398];

}

static void PREP_io_800_writeb (void *opaque, uint32_t addr, uint32_t val)

{

    sysctrl_t *sysctrl = opaque;

    PPC_IO_DPRINTF("0x%08lx => 0x%08x\n", (long)addr - PPC_IO_BASE, val);

    switch (addr) {

    case 0x0092:

        /* Special port 92 */

        /* Check soft reset asked */

        if (val & 0x01) {

            qemu_irq_raise(sysctrl->reset_irq);

        } else {

            qemu_irq_lower(sysctrl->reset_irq);

        }

        /* Check LE mode */

        if (val & 0x02) {

            sysctrl->endian = 1;

        } else {

            sysctrl->endian = 0;

        }

        break;

    case 0x0800:

        /* Motorola CPU configuration register : read-only */

        break;

    case 0x0802:

        /* Motorola base module feature register : read-only */

        break;

    case 0x0803:

        /* Motorola base module status register : read-only */

        break;

    case 0x0808:

        /* Hardfile light register */

        if (val & 1)

            sysctrl->state |= STATE_HARDFILE;

        else

            sysctrl->state &= ~STATE_HARDFILE;

        break;

    case 0x0810:

        /* Password protect 1 register */

        if (sysctrl->nvram != NULL)

            m48t59_toggle_lock(sysctrl->nvram, 1);

        break;

    case 0x0812:

        /* Password protect 2 register */

        if (sysctrl->nvram != NULL)

            m48t59_toggle_lock(sysctrl->nvram, 2);

        break;

    case 0x0814:

        /* L2 invalidate register */

        //        tlb_flush(first_cpu, 1);

        break;

    case 0x081C:

        /* system control register */

        sysctrl->syscontrol = val & 0x0F;

        break;

    case 0x0850:

        /* I/O map type register */

        sysctrl->contiguous_map = val & 0x01;

        break;

    default:

        printf("ERROR: unaffected IO port write: %04lx => %02x\n",

               (long)addr, val);

        break;

    }

}

static uint32_t PREP_io_800_readb (void *opaque, uint32_t addr)

{

    sysctrl_t *sysctrl = opaque;

    uint32_t retval = 0xFF;

    switch (addr) {

    case 0x0092:

        /* Special port 92 */

        retval = 0x00;

        break;

    case 0x0800:

        /* Motorola CPU configuration register */

        retval = 0xEF; /* MPC750 */

        break;

    case 0x0802:

        /* Motorola Base module feature register */

        retval = 0xAD; /* No ESCC, PMC slot neither ethernet */

        break;

    case 0x0803:

        /* Motorola base module status register */

        retval = 0xE0; /* Standard MPC750 */

        break;

    case 0x080C:

        /* Equipment present register:

         *  no L2 cache

         *  no upgrade processor

         *  no cards in PCI slots

         *  SCSI fuse is bad

         */

        retval = 0x3C;

        break;

    case 0x0810:

        /* Motorola base module extended feature register */

        retval = 0x39; /* No USB, CF and PCI bridge. NVRAM present */

        break;

    case 0x0814:

        /* L2 invalidate: don't care */

        break;

    case 0x0818:

        /* Keylock */

        retval = 0x00;

        break;

    case 0x081C:

        /* system control register

         * 7 - 6 / 1 - 0: L2 cache enable

         */

        retval = sysctrl->syscontrol;

        break;

    case 0x0823:

        /* */

        retval = 0x03; /* no L2 cache */

        break;

    case 0x0850:

        /* I/O map type register */

        retval = sysctrl->contiguous_map;

        break;

    default:

        printf("ERROR: unaffected IO port: %04lx read\n", (long)addr);

        break;

    }

    PPC_IO_DPRINTF("0x%08lx <= 0x%08x\n", (long)addr - PPC_IO_BASE, retval);

    return retval;

}

static always_inline target_phys_addr_t prep_IO_address (sysctrl_t *sysctrl,

                                                         target_phys_addr_t

                                                         addr)

{

    if (sysctrl->contiguous_map == 0) {

        /* 64 KB contiguous space for IOs */

        addr &= 0xFFFF;

    } else {

        /* 8 MB non-contiguous space for IOs */

        addr = (addr & 0x1F) | ((addr & 0x007FFF000) >> 7);

    }

    return addr;

}

static void PPC_prep_io_writeb (void *opaque, target_phys_addr_t addr,

                                uint32_t value)

{

    sysctrl_t *sysctrl = opaque;

    addr = prep_IO_address(sysctrl, addr);

    cpu_outb(NULL, addr, value);

}

static uint32_t PPC_prep_io_readb (void *opaque, target_phys_addr_t addr)

{

    sysctrl_t *sysctrl = opaque;

    uint32_t ret;

    addr = prep_IO_address(sysctrl, addr);

    ret = cpu_inb(NULL, addr);

    return ret;

}

static void PPC_prep_io_writew (void *opaque, target_phys_addr_t addr,

                                uint32_t value)

{

    sysctrl_t *sysctrl = opaque;

    addr = prep_IO_address(sysctrl, addr);

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap16(value);

#endif

    PPC_IO_DPRINTF("0x%08lx => 0x%08x\n", (long)addr, value);

    cpu_outw(NULL, addr, value);

}

static uint32_t PPC_prep_io_readw (void *opaque, target_phys_addr_t addr)

{

    sysctrl_t *sysctrl = opaque;

    uint32_t ret;

    addr = prep_IO_address(sysctrl, addr);

    ret = cpu_inw(NULL, addr);

#ifdef TARGET_WORDS_BIGENDIAN

    ret = bswap16(ret);

#endif

    PPC_IO_DPRINTF("0x%08lx <= 0x%08x\n", (long)addr, ret);

    return ret;

}

static void PPC_prep_io_writel (void *opaque, target_phys_addr_t addr,

                                uint32_t value)

{

    sysctrl_t *sysctrl = opaque;

    addr = prep_IO_address(sysctrl, addr);

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap32(value);

#endif

    PPC_IO_DPRINTF("0x%08lx => 0x%08x\n", (long)addr, value);

    cpu_outl(NULL, addr, value);

}

static uint32_t PPC_prep_io_readl (void *opaque, target_phys_addr_t addr)

{

    sysctrl_t *sysctrl = opaque;

    uint32_t ret;

    addr = prep_IO_address(sysctrl, addr);

    ret = cpu_inl(NULL, addr);

#ifdef TARGET_WORDS_BIGENDIAN

    ret = bswap32(ret);

#endif

    PPC_IO_DPRINTF("0x%08lx <= 0x%08x\n", (long)addr, ret);

    return ret;

}

CPUWriteMemoryFunc *PPC_prep_io_write[] = {

    &PPC_prep_io_writeb,

    &PPC_prep_io_writew,

    &PPC_prep_io_writel,

};

CPUReadMemoryFunc *PPC_prep_io_read[] = {

    &PPC_prep_io_readb,

    &PPC_prep_io_readw,

    &PPC_prep_io_readl,

};

#define NVRAM_SIZE        0x2000

/* PowerPC PREP hardware initialisation */

static void ppc_prep_init (int ram_size, int vga_ram_size,

                           const char *boot_device,

                           DisplayState *ds, const char **fd_filename,

                           int snapshot, const char *kernel_filename,

                           const char *kernel_cmdline,

                           const char *initrd_filename,

                           const char *cpu_model)

{

    CPUState *env = NULL, *envs[MAX_CPUS];

    char buf[1024];

    nvram_t nvram;

    m48t59_t *m48t59;

    int PPC_io_memory;

    int linux_boot, i, nb_nics1, bios_size;

    unsigned long bios_offset;

    uint32_t kernel_base, kernel_size, initrd_base, initrd_size;

    PCIBus *pci_bus;

    qemu_irq *i8259;

    int ppc_boot_device;

    sysctrl = qemu_mallocz(sizeof(sysctrl_t));

    if (sysctrl == NULL)

        return;

    linux_boot = (kernel_filename != NULL);

    /* init CPUs */

    if (cpu_model == NULL)

        cpu_model = "default";

    for (i = 0; i < smp_cpus; i++) {

        env = cpu_init(cpu_model);

        if (!env) {

            fprintf(stderr, "Unable to find PowerPC CPU definition\n");

            exit(1);

        }

        /* Set time-base frequency to 100 Mhz */

        cpu_ppc_tb_init(env, 100UL * 1000UL * 1000UL);

        qemu_register_reset(&cpu_ppc_reset, env);

        register_savevm("cpu", 0, 3, cpu_save, cpu_load, env);

        envs[i] = env;

    }

    /* allocate RAM */

    cpu_register_physical_memory(0, ram_size, IO_MEM_RAM);

    /* allocate and load BIOS */

    bios_offset = ram_size + vga_ram_size;

    if (bios_name == NULL)

        bios_name = BIOS_FILENAME;

    snprintf(buf, sizeof(buf), "%s/%s", bios_dir, bios_name);

    bios_size = load_image(buf, phys_ram_base + bios_offset);

    if (bios_size < 0 || bios_size > BIOS_SIZE) {

        cpu_abort(env, "qemu: could not load PPC PREP bios '%s'\n", buf);

        exit(1);

    }

    if (env->nip < 0xFFF80000 && bios_size < 0x00100000) {

        cpu_abort(env, "PowerPC 601 / 620 / 970 need a 1MB BIOS\n");

    }

    bios_size = (bios_size + 0xfff) & ~0xfff;

    cpu_register_physical_memory((uint32_t)(-bios_size),

                                 bios_size, bios_offset | IO_MEM_ROM);

    if (linux_boot) {

        kernel_base = KERNEL_LOAD_ADDR;

        /* now we can load the kernel */

        kernel_size = load_image(kernel_filename, phys_ram_base + kernel_base);

        if (kernel_size < 0) {

            cpu_abort(env, "qemu: could not load kernel '%s'\n",

                      kernel_filename);

            exit(1);

        }

        /* load initrd */

        if (initrd_filename) {

            initrd_base = INITRD_LOAD_ADDR;

            initrd_size = load_image(initrd_filename,

                                     phys_ram_base + initrd_base);

            if (initrd_size < 0) {

                cpu_abort(env, "qemu: could not load initial ram disk '%s'\n",

                          initrd_filename);

                exit(1);

            }

        } else {

            initrd_base = 0;

            initrd_size = 0;

        }

        ppc_boot_device = 'm';

    } else {

        kernel_base = 0;

        kernel_size = 0;

        initrd_base = 0;

        initrd_size = 0;

        ppc_boot_device = '\0';

        /* For now, OHW cannot boot from the network. */

        for (i = 0; boot_device[i] != '\0'; i++) {

            if (boot_device[i] >= 'a' && boot_device[i] <= 'f') {

                ppc_boot_device = boot_device[i];

                break;

            }

        }

        if (ppc_boot_device == '\0') {

            fprintf(stderr, "No valid boot device for Mac99 machine\n");

            exit(1);

        }

    }

    isa_mem_base = 0xc0000000;

    if (PPC_INPUT(env) != PPC_FLAGS_INPUT_6xx) {

        cpu_abort(env, "Only 6xx bus is supported on PREP machine\n");

        exit(1);

    }

    i8259 = i8259_init(first_cpu->irq_inputs[PPC6xx_INPUT_INT]);

    pci_bus = pci_prep_init(i8259);

    //    pci_bus = i440fx_init();

    /* Register 8 MB of ISA IO space (needed for non-contiguous map) */

    PPC_io_memory = cpu_register_io_memory(0, PPC_prep_io_read,

                                           PPC_prep_io_write, sysctrl);

    cpu_register_physical_memory(0x80000000, 0x00800000, PPC_io_memory);

    /* init basic PC hardware */

    pci_vga_init(pci_bus, ds, phys_ram_base + ram_size, ram_size,

                 vga_ram_size, 0, 0);

    //    openpic = openpic_init(0x00000000, 0xF0000000, 1);

    //    pit = pit_init(0x40, i8259[0]);

    rtc_init(0x70, i8259[8]);

    serial_init(0x3f8, i8259[4], serial_hds[0]);

    nb_nics1 = nb_nics;

    if (nb_nics1 > NE2000_NB_MAX)

        nb_nics1 = NE2000_NB_MAX;

    for(i = 0; i < nb_nics1; i++) {

        if (nd_table[i].model == NULL

            || strcmp(nd_table[i].model, "ne2k_isa") == 0) {

            isa_ne2000_init(ne2000_io[i], i8259[ne2000_irq[i]], &nd_table[i]);

        } else {

            pci_nic_init(pci_bus, &nd_table[i], -1);

        }

    }

    for(i = 0; i < 2; i++) {

        isa_ide_init(ide_iobase[i], ide_iobase2[i], i8259[ide_irq[i]],

                     bs_table[2 * i], bs_table[2 * i + 1]);

    }

    i8042_init(i8259[1], i8259[12], 0x60);

    DMA_init(1);

    //    AUD_init();

    //    SB16_init();

    fdctrl_init(i8259[6], 2, 0, 0x3f0, fd_table);

    /* Register speaker port */

    register_ioport_read(0x61, 1, 1, speaker_ioport_read, NULL);

    register_ioport_write(0x61, 1, 1, speaker_ioport_write, NULL);

    /* Register fake IO ports for PREP */

    sysctrl->reset_irq = first_cpu->irq_inputs[PPC6xx_INPUT_HRESET];

    register_ioport_read(0x398, 2, 1, &PREP_io_read, sysctrl);

    register_ioport_write(0x398, 2, 1, &PREP_io_write, sysctrl);

    /* System control ports */

    register_ioport_read(0x0092, 0x01, 1, &PREP_io_800_readb, sysctrl);

    register_ioport_write(0x0092, 0x01, 1, &PREP_io_800_writeb, sysctrl);

    register_ioport_read(0x0800, 0x52, 1, &PREP_io_800_readb, sysctrl);

    register_ioport_write(0x0800, 0x52, 1, &PREP_io_800_writeb, sysctrl);

    /* PCI intack location */

    PPC_io_memory = cpu_register_io_memory(0, PPC_intack_read,

                                           PPC_intack_write, NULL);

    cpu_register_physical_memory(0xBFFFFFF0, 0x4, PPC_io_memory);

    /* PowerPC control and status register group */

#if 0

    PPC_io_memory = cpu_register_io_memory(0, PPC_XCSR_read, PPC_XCSR_write,

                                           NULL);

    cpu_register_physical_memory(0xFEFF0000, 0x1000, PPC_io_memory);

#endif

    if (usb_enabled) {

        usb_ohci_init_pci(pci_bus, 3, -1);

    }

    m48t59 = m48t59_init(i8259[8], 0, 0x0074, NVRAM_SIZE, 59);

    if (m48t59 == NULL)

        return;

    sysctrl->nvram = m48t59;

    /* Initialise NVRAM */

    nvram.opaque = m48t59;

    nvram.read_fn = &m48t59_read;

    nvram.write_fn = &m48t59_write;

    PPC_NVRAM_set_params(&nvram, NVRAM_SIZE, "PREP", ram_size, ppc_boot_device,

                         kernel_base, kernel_size,

                         kernel_cmdline,

                         initrd_base, initrd_size,

                         /* XXX: need an option to load a NVRAM image */

                         0,

                         graphic_width, graphic_height, graphic_depth);

    /* Special port to get debug messages from Open-Firmware */

    register_ioport_write(0x0F00, 4, 1, &PPC_debug_write, NULL);

}

QEMUMachine prep_machine = {

    "prep",

    "PowerPC PREP platform",

    ppc_prep_init,

};