Archipelago » qemu

/*

 * QEMU ESCC (Z8030/Z8530/Z85C30/SCC/ESCC) serial port emulation

 *

 * Copyright (c) 2003-2005 Fabrice Bellard

 *

 * 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 "escc.h"

#include "qemu-char.h"

#include "console.h"

/* debug serial */

//#define DEBUG_SERIAL

/* debug keyboard */

//#define DEBUG_KBD

/* debug mouse */

//#define DEBUG_MOUSE

/*

 * On Sparc32 this is the serial port, mouse and keyboard part of chip STP2001

 * (Slave I/O), also produced as NCR89C105. See

 * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt

 *

 * The serial ports implement full AMD AM8530 or Zilog Z8530 chips,

 * mouse and keyboard ports don't implement all functions and they are

 * only asynchronous. There is no DMA.

 *

 * Z85C30 is also used on PowerMacs. There are some small differences

 * between Sparc version (sunzilog) and PowerMac (pmac):

 *  Offset between control and data registers

 *  There is some kind of lockup bug, but we can ignore it

 *  CTS is inverted

 *  DMA on pmac using DBDMA chip

 *  pmac can do IRDA and faster rates, sunzilog can only do 38400

 *  pmac baud rate generator clock is 3.6864 MHz, sunzilog 4.9152 MHz

 */

/*

 * Modifications:

 *  2006-Aug-10  Igor Kovalenko :   Renamed KBDQueue to SERIOQueue, implemented

 *                                  serial mouse queue.

 *                                  Implemented serial mouse protocol.

 */

#ifdef DEBUG_SERIAL

#define SER_DPRINTF(fmt, ...)                                   \

    do { printf("SER: " fmt , ## __VA_ARGS__); } while (0)

#else

#define SER_DPRINTF(fmt, ...)

#endif

#ifdef DEBUG_KBD

#define KBD_DPRINTF(fmt, ...)                                   \

    do { printf("KBD: " fmt , ## __VA_ARGS__); } while (0)

#else

#define KBD_DPRINTF(fmt, ...)

#endif

#ifdef DEBUG_MOUSE

#define MS_DPRINTF(fmt, ...)                                    \

    do { printf("MSC: " fmt , ## __VA_ARGS__); } while (0)

#else

#define MS_DPRINTF(fmt, ...)

#endif

typedef enum {

    chn_a, chn_b,

} chn_id_t;

#define CHN_C(s) ((s)->chn == chn_b? 'b' : 'a')

typedef enum {

    ser, kbd, mouse,

} chn_type_t;

#define SERIO_QUEUE_SIZE 256

typedef struct {

    uint8_t data[SERIO_QUEUE_SIZE];

    int rptr, wptr, count;

} SERIOQueue;

#define SERIAL_REGS 16

typedef struct ChannelState {

    qemu_irq irq;

    uint32_t reg;

    uint32_t rxint, txint, rxint_under_svc, txint_under_svc;

    chn_id_t chn; // this channel, A (base+4) or B (base+0)

    chn_type_t type;

    struct ChannelState *otherchn;

    uint8_t rx, tx, wregs[SERIAL_REGS], rregs[SERIAL_REGS];

    SERIOQueue queue;

    CharDriverState *chr;

    int e0_mode, led_mode, caps_lock_mode, num_lock_mode;

    int disabled;

    int clock;

} ChannelState;

struct SerialState {

    struct ChannelState chn[2];

    int it_shift;

};

#define SERIAL_CTRL 0

#define SERIAL_DATA 1

#define W_CMD     0

#define CMD_PTR_MASK   0x07

#define CMD_CMD_MASK   0x38

#define CMD_HI         0x08

#define CMD_CLR_TXINT  0x28

#define CMD_CLR_IUS    0x38

#define W_INTR    1

#define INTR_INTALL    0x01

#define INTR_TXINT     0x02

#define INTR_RXMODEMSK 0x18

#define INTR_RXINT1ST  0x08

#define INTR_RXINTALL  0x10

#define W_IVEC    2

#define W_RXCTRL  3

#define RXCTRL_RXEN    0x01

#define W_TXCTRL1 4

#define TXCTRL1_PAREN  0x01

#define TXCTRL1_PAREV  0x02

#define TXCTRL1_1STOP  0x04

#define TXCTRL1_1HSTOP 0x08

#define TXCTRL1_2STOP  0x0c

#define TXCTRL1_STPMSK 0x0c

#define TXCTRL1_CLK1X  0x00

#define TXCTRL1_CLK16X 0x40

#define TXCTRL1_CLK32X 0x80

#define TXCTRL1_CLK64X 0xc0

#define TXCTRL1_CLKMSK 0xc0

#define W_TXCTRL2 5

#define TXCTRL2_TXEN   0x08

#define TXCTRL2_BITMSK 0x60

#define TXCTRL2_5BITS  0x00

#define TXCTRL2_7BITS  0x20

#define TXCTRL2_6BITS  0x40

#define TXCTRL2_8BITS  0x60

#define W_SYNC1   6

#define W_SYNC2   7

#define W_TXBUF   8

#define W_MINTR   9

#define MINTR_STATUSHI 0x10

#define MINTR_RST_MASK 0xc0

#define MINTR_RST_B    0x40

#define MINTR_RST_A    0x80

#define MINTR_RST_ALL  0xc0

#define W_MISC1  10

#define W_CLOCK  11

#define CLOCK_TRXC     0x08

#define W_BRGLO  12

#define W_BRGHI  13

#define W_MISC2  14

#define MISC2_PLLDIS   0x30

#define W_EXTINT 15

#define EXTINT_DCD     0x08

#define EXTINT_SYNCINT 0x10

#define EXTINT_CTSINT  0x20

#define EXTINT_TXUNDRN 0x40

#define EXTINT_BRKINT  0x80

#define R_STATUS  0

#define STATUS_RXAV    0x01

#define STATUS_ZERO    0x02

#define STATUS_TXEMPTY 0x04

#define STATUS_DCD     0x08

#define STATUS_SYNC    0x10

#define STATUS_CTS     0x20

#define STATUS_TXUNDRN 0x40

#define STATUS_BRK     0x80

#define R_SPEC    1

#define SPEC_ALLSENT   0x01

#define SPEC_BITS8     0x06

#define R_IVEC    2

#define IVEC_TXINTB    0x00

#define IVEC_LONOINT   0x06

#define IVEC_LORXINTA  0x0c

#define IVEC_LORXINTB  0x04

#define IVEC_LOTXINTA  0x08

#define IVEC_HINOINT   0x60

#define IVEC_HIRXINTA  0x30

#define IVEC_HIRXINTB  0x20

#define IVEC_HITXINTA  0x10

#define R_INTR    3

#define INTR_EXTINTB   0x01

#define INTR_TXINTB    0x02

#define INTR_RXINTB    0x04

#define INTR_EXTINTA   0x08

#define INTR_TXINTA    0x10

#define INTR_RXINTA    0x20

#define R_IPEN    4

#define R_TXCTRL1 5

#define R_TXCTRL2 6

#define R_BC      7

#define R_RXBUF   8

#define R_RXCTRL  9

#define R_MISC   10

#define R_MISC1  11

#define R_BRGLO  12

#define R_BRGHI  13

#define R_MISC1I 14

#define R_EXTINT 15

static void handle_kbd_command(ChannelState *s, int val);

static int serial_can_receive(void *opaque);

static void serial_receive_byte(ChannelState *s, int ch);

static void clear_queue(void *opaque)

{

    ChannelState *s = opaque;

    SERIOQueue *q = &s->queue;

    q->rptr = q->wptr = q->count = 0;

}

static void put_queue(void *opaque, int b)

{

    ChannelState *s = opaque;

    SERIOQueue *q = &s->queue;

    SER_DPRINTF("channel %c put: 0x%02x\n", CHN_C(s), b);

    if (q->count >= SERIO_QUEUE_SIZE)

        return;

    q->data[q->wptr] = b;

    if (++q->wptr == SERIO_QUEUE_SIZE)

        q->wptr = 0;

    q->count++;

    serial_receive_byte(s, 0);

}

static uint32_t get_queue(void *opaque)

{

    ChannelState *s = opaque;

    SERIOQueue *q = &s->queue;

    int val;

    if (q->count == 0) {

        return 0;

    } else {

        val = q->data[q->rptr];

        if (++q->rptr == SERIO_QUEUE_SIZE)

            q->rptr = 0;

        q->count--;

    }

    SER_DPRINTF("channel %c get 0x%02x\n", CHN_C(s), val);

    if (q->count > 0)

        serial_receive_byte(s, 0);

    return val;

}

static int escc_update_irq_chn(ChannelState *s)

{

    if ((((s->wregs[W_INTR] & INTR_TXINT) && s->txint == 1) ||

         // tx ints enabled, pending

         ((((s->wregs[W_INTR] & INTR_RXMODEMSK) == INTR_RXINT1ST) ||

           ((s->wregs[W_INTR] & INTR_RXMODEMSK) == INTR_RXINTALL)) &&

          s->rxint == 1) || // rx ints enabled, pending

         ((s->wregs[W_EXTINT] & EXTINT_BRKINT) &&

          (s->rregs[R_STATUS] & STATUS_BRK)))) { // break int e&p

        return 1;

    }

    return 0;

}

static void escc_update_irq(ChannelState *s)

{

    int irq;

    irq = escc_update_irq_chn(s);

    irq |= escc_update_irq_chn(s->otherchn);

    SER_DPRINTF("IRQ = %d\n", irq);

    qemu_set_irq(s->irq, irq);

}

static void escc_reset_chn(ChannelState *s)

{

    int i;

    s->reg = 0;

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

        s->rregs[i] = 0;

        s->wregs[i] = 0;

    }

    s->wregs[W_TXCTRL1] = TXCTRL1_1STOP; // 1X divisor, 1 stop bit, no parity

    s->wregs[W_MINTR] = MINTR_RST_ALL;

    s->wregs[W_CLOCK] = CLOCK_TRXC; // Synch mode tx clock = TRxC

    s->wregs[W_MISC2] = MISC2_PLLDIS; // PLL disabled

    s->wregs[W_EXTINT] = EXTINT_DCD | EXTINT_SYNCINT | EXTINT_CTSINT |

        EXTINT_TXUNDRN | EXTINT_BRKINT; // Enable most interrupts

    if (s->disabled)

        s->rregs[R_STATUS] = STATUS_TXEMPTY | STATUS_DCD | STATUS_SYNC |

            STATUS_CTS | STATUS_TXUNDRN;

    else

        s->rregs[R_STATUS] = STATUS_TXEMPTY | STATUS_TXUNDRN;

    s->rregs[R_SPEC] = SPEC_BITS8 | SPEC_ALLSENT;

    s->rx = s->tx = 0;

    s->rxint = s->txint = 0;

    s->rxint_under_svc = s->txint_under_svc = 0;

    s->e0_mode = s->led_mode = s->caps_lock_mode = s->num_lock_mode = 0;

    clear_queue(s);

}

static void escc_reset(void *opaque)

{

    SerialState *s = opaque;

    escc_reset_chn(&s->chn[0]);

    escc_reset_chn(&s->chn[1]);

}

static inline void set_rxint(ChannelState *s)

{

    s->rxint = 1;

    if (!s->txint_under_svc) {

        s->rxint_under_svc = 1;

        if (s->chn == chn_a) {

            if (s->wregs[W_MINTR] & MINTR_STATUSHI)

                s->otherchn->rregs[R_IVEC] = IVEC_HIRXINTA;

            else

                s->otherchn->rregs[R_IVEC] = IVEC_LORXINTA;

        } else {

            if (s->wregs[W_MINTR] & MINTR_STATUSHI)

                s->rregs[R_IVEC] = IVEC_HIRXINTB;

            else

                s->rregs[R_IVEC] = IVEC_LORXINTB;

        }

    }

    if (s->chn == chn_a)

        s->rregs[R_INTR] |= INTR_RXINTA;

    else

        s->otherchn->rregs[R_INTR] |= INTR_RXINTB;

    escc_update_irq(s);

}

static inline void set_txint(ChannelState *s)

{

    s->txint = 1;

    if (!s->rxint_under_svc) {

        s->txint_under_svc = 1;

        if (s->chn == chn_a) {

            if (s->wregs[W_MINTR] & MINTR_STATUSHI)

                s->otherchn->rregs[R_IVEC] = IVEC_HITXINTA;

            else

                s->otherchn->rregs[R_IVEC] = IVEC_LOTXINTA;

        } else {

            s->rregs[R_IVEC] = IVEC_TXINTB;

        }

    }

    if (s->chn == chn_a)

        s->rregs[R_INTR] |= INTR_TXINTA;

    else

        s->otherchn->rregs[R_INTR] |= INTR_TXINTB;

    escc_update_irq(s);

}

static inline void clr_rxint(ChannelState *s)

{

    s->rxint = 0;

    s->rxint_under_svc = 0;

    if (s->chn == chn_a) {

        if (s->wregs[W_MINTR] & MINTR_STATUSHI)

            s->otherchn->rregs[R_IVEC] = IVEC_HINOINT;

        else

            s->otherchn->rregs[R_IVEC] = IVEC_LONOINT;

        s->rregs[R_INTR] &= ~INTR_RXINTA;

    } else {

        if (s->wregs[W_MINTR] & MINTR_STATUSHI)

            s->rregs[R_IVEC] = IVEC_HINOINT;

        else

            s->rregs[R_IVEC] = IVEC_LONOINT;

        s->otherchn->rregs[R_INTR] &= ~INTR_RXINTB;

    }

    if (s->txint)

        set_txint(s);

    escc_update_irq(s);

}

static inline void clr_txint(ChannelState *s)

{

    s->txint = 0;

    s->txint_under_svc = 0;

    if (s->chn == chn_a) {

        if (s->wregs[W_MINTR] & MINTR_STATUSHI)

            s->otherchn->rregs[R_IVEC] = IVEC_HINOINT;

        else

            s->otherchn->rregs[R_IVEC] = IVEC_LONOINT;

        s->rregs[R_INTR] &= ~INTR_TXINTA;

    } else {

        if (s->wregs[W_MINTR] & MINTR_STATUSHI)

            s->rregs[R_IVEC] = IVEC_HINOINT;

        else

            s->rregs[R_IVEC] = IVEC_LONOINT;

        s->otherchn->rregs[R_INTR] &= ~INTR_TXINTB;

    }

    if (s->rxint)

        set_rxint(s);

    escc_update_irq(s);

}

static void escc_update_parameters(ChannelState *s)

{

    int speed, parity, data_bits, stop_bits;

    QEMUSerialSetParams ssp;

    if (!s->chr || s->type != ser)

        return;

    if (s->wregs[W_TXCTRL1] & TXCTRL1_PAREN) {

        if (s->wregs[W_TXCTRL1] & TXCTRL1_PAREV)

            parity = 'E';

        else

            parity = 'O';

    } else {

        parity = 'N';

    }

    if ((s->wregs[W_TXCTRL1] & TXCTRL1_STPMSK) == TXCTRL1_2STOP)

        stop_bits = 2;

    else

        stop_bits = 1;

    switch (s->wregs[W_TXCTRL2] & TXCTRL2_BITMSK) {

    case TXCTRL2_5BITS:

        data_bits = 5;

        break;

    case TXCTRL2_7BITS:

        data_bits = 7;

        break;

    case TXCTRL2_6BITS:

        data_bits = 6;

        break;

    default:

    case TXCTRL2_8BITS:

        data_bits = 8;

        break;

    }

    speed = s->clock / ((s->wregs[W_BRGLO] | (s->wregs[W_BRGHI] << 8)) + 2);

    switch (s->wregs[W_TXCTRL1] & TXCTRL1_CLKMSK) {

    case TXCTRL1_CLK1X:

        break;

    case TXCTRL1_CLK16X:

        speed /= 16;

        break;

    case TXCTRL1_CLK32X:

        speed /= 32;

        break;

    default:

    case TXCTRL1_CLK64X:

        speed /= 64;

        break;

    }

    ssp.speed = speed;

    ssp.parity = parity;

    ssp.data_bits = data_bits;

    ssp.stop_bits = stop_bits;

    SER_DPRINTF("channel %c: speed=%d parity=%c data=%d stop=%d\n", CHN_C(s),

                speed, parity, data_bits, stop_bits);

    qemu_chr_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);

}

static void escc_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)

{

    SerialState *serial = opaque;

    ChannelState *s;

    uint32_t saddr;

    int newreg, channel;

    val &= 0xff;

    saddr = (addr >> serial->it_shift) & 1;

    channel = (addr >> (serial->it_shift + 1)) & 1;

    s = &serial->chn[channel];

    switch (saddr) {

    case SERIAL_CTRL:

        SER_DPRINTF("Write channel %c, reg[%d] = %2.2x\n", CHN_C(s), s->reg,

                    val & 0xff);

        newreg = 0;

        switch (s->reg) {

        case W_CMD:

            newreg = val & CMD_PTR_MASK;

            val &= CMD_CMD_MASK;

            switch (val) {

            case CMD_HI:

                newreg |= CMD_HI;

                break;

            case CMD_CLR_TXINT:

                clr_txint(s);

                break;

            case CMD_CLR_IUS:

                if (s->rxint_under_svc)

                    clr_rxint(s);

                else if (s->txint_under_svc)

                    clr_txint(s);

                break;

            default:

                break;

            }

            break;

        case W_INTR ... W_RXCTRL:

        case W_SYNC1 ... W_TXBUF:

        case W_MISC1 ... W_CLOCK:

        case W_MISC2 ... W_EXTINT:

            s->wregs[s->reg] = val;

            break;

        case W_TXCTRL1:

        case W_TXCTRL2:

            s->wregs[s->reg] = val;

            escc_update_parameters(s);

            break;

        case W_BRGLO:

        case W_BRGHI:

            s->wregs[s->reg] = val;

            s->rregs[s->reg] = val;

            escc_update_parameters(s);

            break;

        case W_MINTR:

            switch (val & MINTR_RST_MASK) {

            case 0:

            default:

                break;

            case MINTR_RST_B:

                escc_reset_chn(&serial->chn[0]);

                return;

            case MINTR_RST_A:

                escc_reset_chn(&serial->chn[1]);

                return;

            case MINTR_RST_ALL:

                escc_reset(serial);

                return;

            }

            break;

        default:

            break;

        }

        if (s->reg == 0)

            s->reg = newreg;

        else

            s->reg = 0;

        break;

    case SERIAL_DATA:

        SER_DPRINTF("Write channel %c, ch %d\n", CHN_C(s), val);

        s->tx = val;

        if (s->wregs[W_TXCTRL2] & TXCTRL2_TXEN) { // tx enabled

            if (s->chr)

                qemu_chr_write(s->chr, &s->tx, 1);

            else if (s->type == kbd && !s->disabled) {

                handle_kbd_command(s, val);

            }

        }

        s->rregs[R_STATUS] |= STATUS_TXEMPTY; // Tx buffer empty

        s->rregs[R_SPEC] |= SPEC_ALLSENT; // All sent

        set_txint(s);

        break;

    default:

        break;

    }

}

static uint32_t escc_mem_readb(void *opaque, target_phys_addr_t addr)

{

    SerialState *serial = opaque;

    ChannelState *s;

    uint32_t saddr;

    uint32_t ret;

    int channel;

    saddr = (addr >> serial->it_shift) & 1;

    channel = (addr >> (serial->it_shift + 1)) & 1;

    s = &serial->chn[channel];

    switch (saddr) {

    case SERIAL_CTRL:

        SER_DPRINTF("Read channel %c, reg[%d] = %2.2x\n", CHN_C(s), s->reg,

                    s->rregs[s->reg]);

        ret = s->rregs[s->reg];

        s->reg = 0;

        return ret;

    case SERIAL_DATA:

        s->rregs[R_STATUS] &= ~STATUS_RXAV;

        clr_rxint(s);

        if (s->type == kbd || s->type == mouse)

            ret = get_queue(s);

        else

            ret = s->rx;

        SER_DPRINTF("Read channel %c, ch %d\n", CHN_C(s), ret);

        if (s->chr)

            qemu_chr_accept_input(s->chr);

        return ret;

    default:

        break;

    }

    return 0;

}

static int serial_can_receive(void *opaque)

{

    ChannelState *s = opaque;

    int ret;

    if (((s->wregs[W_RXCTRL] & RXCTRL_RXEN) == 0) // Rx not enabled

        || ((s->rregs[R_STATUS] & STATUS_RXAV) == STATUS_RXAV))

        // char already available

        ret = 0;

    else

        ret = 1;

    return ret;

}

static void serial_receive_byte(ChannelState *s, int ch)

{

    SER_DPRINTF("channel %c put ch %d\n", CHN_C(s), ch);

    s->rregs[R_STATUS] |= STATUS_RXAV;

    s->rx = ch;

    set_rxint(s);

}

static void serial_receive_break(ChannelState *s)

{

    s->rregs[R_STATUS] |= STATUS_BRK;

    escc_update_irq(s);

}

static void serial_receive1(void *opaque, const uint8_t *buf, int size)

{

    ChannelState *s = opaque;

    serial_receive_byte(s, buf[0]);

}

static void serial_event(void *opaque, int event)

{

    ChannelState *s = opaque;

    if (event == CHR_EVENT_BREAK)

        serial_receive_break(s);

}

static CPUReadMemoryFunc *escc_mem_read[3] = {

    escc_mem_readb,

    NULL,

    NULL,

};

static CPUWriteMemoryFunc *escc_mem_write[3] = {

    escc_mem_writeb,

    NULL,

    NULL,

};

static void escc_save_chn(QEMUFile *f, ChannelState *s)

{

    uint32_t tmp = 0;

    qemu_put_be32s(f, &tmp); /* unused, was IRQ.  */

    qemu_put_be32s(f, &s->reg);

    qemu_put_be32s(f, &s->rxint);

    qemu_put_be32s(f, &s->txint);

    qemu_put_be32s(f, &s->rxint_under_svc);

    qemu_put_be32s(f, &s->txint_under_svc);

    qemu_put_8s(f, &s->rx);

    qemu_put_8s(f, &s->tx);

    qemu_put_buffer(f, s->wregs, SERIAL_REGS);

    qemu_put_buffer(f, s->rregs, SERIAL_REGS);

}

static void escc_save(QEMUFile *f, void *opaque)

{

    SerialState *s = opaque;

    escc_save_chn(f, &s->chn[0]);

    escc_save_chn(f, &s->chn[1]);

}

static int escc_load_chn(QEMUFile *f, ChannelState *s, int version_id)

{

    uint32_t tmp;

    if (version_id > 2)

        return -EINVAL;

    qemu_get_be32s(f, &tmp); /* unused */

    qemu_get_be32s(f, &s->reg);

    qemu_get_be32s(f, &s->rxint);

    qemu_get_be32s(f, &s->txint);

    if (version_id >= 2) {

        qemu_get_be32s(f, &s->rxint_under_svc);

        qemu_get_be32s(f, &s->txint_under_svc);

    }

    qemu_get_8s(f, &s->rx);

    qemu_get_8s(f, &s->tx);

    qemu_get_buffer(f, s->wregs, SERIAL_REGS);

    qemu_get_buffer(f, s->rregs, SERIAL_REGS);

    return 0;

}

static int escc_load(QEMUFile *f, void *opaque, int version_id)

{

    SerialState *s = opaque;

    int ret;

    ret = escc_load_chn(f, &s->chn[0], version_id);

    if (ret != 0)

        return ret;

    ret = escc_load_chn(f, &s->chn[1], version_id);

    return ret;

}

int escc_init(target_phys_addr_t base, qemu_irq irqA, qemu_irq irqB,

              CharDriverState *chrA, CharDriverState *chrB,

              int clock, int it_shift)

{

    int escc_io_memory, i;

    SerialState *s;

    s = qemu_mallocz(sizeof(SerialState));

    escc_io_memory = cpu_register_io_memory(0, escc_mem_read,

                                            escc_mem_write,

                                            s);

    if (base)

        cpu_register_physical_memory(base, ESCC_SIZE << it_shift,

                                     escc_io_memory);

    s->it_shift = it_shift;

    s->chn[0].chr = chrB;

    s->chn[1].chr = chrA;

    s->chn[0].disabled = 0;

    s->chn[1].disabled = 0;

    s->chn[0].irq = irqB;

    s->chn[1].irq = irqA;

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

        s->chn[i].chn = 1 - i;

        s->chn[i].type = ser;

        s->chn[i].clock = clock / 2;

        if (s->chn[i].chr) {

            qemu_chr_add_handlers(s->chn[i].chr, serial_can_receive,

                                  serial_receive1, serial_event, &s->chn[i]);

        }

    }

    s->chn[0].otherchn = &s->chn[1];

    s->chn[1].otherchn = &s->chn[0];

    if (base)

        register_savevm("escc", base, 2, escc_save, escc_load, s);

    else

        register_savevm("escc", -1, 2, escc_save, escc_load, s);

    qemu_register_reset(escc_reset, 0, s);

    escc_reset(s);

    return escc_io_memory;

}

static const uint8_t keycodes[128] = {

    127, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 43, 53,

    54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 89, 76, 77, 78,

    79, 80, 81, 82, 83, 84, 85, 86, 87, 42, 99, 88, 100, 101, 102, 103,

    104, 105, 106, 107, 108, 109, 110, 47, 19, 121, 119, 5, 6, 8, 10, 12,

    14, 16, 17, 18, 7, 98, 23, 68, 69, 70, 71, 91, 92, 93, 125, 112,

    113, 114, 94, 50, 0, 0, 124, 9, 11, 0, 0, 0, 0, 0, 0, 0,

    90, 0, 46, 22, 13, 111, 52, 20, 96, 24, 28, 74, 27, 123, 44, 66,

    0, 45, 2, 4, 48, 0, 0, 21, 0, 0, 0, 0, 0, 120, 122, 67,

};

static const uint8_t e0_keycodes[128] = {

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 90, 76, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 109, 0, 0, 13, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 68, 69, 70, 0, 91, 0, 93, 0, 112,

    113, 114, 94, 50, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    1, 3, 25, 26, 49, 52, 72, 73, 97, 99, 111, 118, 120, 122, 67, 0,

};

static void sunkbd_event(void *opaque, int ch)

{

    ChannelState *s = opaque;

    int release = ch & 0x80;

    KBD_DPRINTF("Untranslated keycode %2.2x (%s)\n", ch, release? "release" :

                "press");

    switch (ch) {

    case 58: // Caps lock press

        s->caps_lock_mode ^= 1;

        if (s->caps_lock_mode == 2)

            return; // Drop second press

        break;

    case 69: // Num lock press

        s->num_lock_mode ^= 1;

        if (s->num_lock_mode == 2)

            return; // Drop second press

        break;

    case 186: // Caps lock release

        s->caps_lock_mode ^= 2;

        if (s->caps_lock_mode == 3)

            return; // Drop first release

        break;

    case 197: // Num lock release

        s->num_lock_mode ^= 2;

        if (s->num_lock_mode == 3)

            return; // Drop first release

        break;

    case 0xe0:

        s->e0_mode = 1;

        return;

    default:

        break;

    }

    if (s->e0_mode) {

        s->e0_mode = 0;

        ch = e0_keycodes[ch & 0x7f];

    } else {

        ch = keycodes[ch & 0x7f];

    }

    KBD_DPRINTF("Translated keycode %2.2x\n", ch);

    put_queue(s, ch | release);

}

static void handle_kbd_command(ChannelState *s, int val)

{

    KBD_DPRINTF("Command %d\n", val);

    if (s->led_mode) { // Ignore led byte

        s->led_mode = 0;

        return;

    }

    switch (val) {

    case 1: // Reset, return type code

        clear_queue(s);

        put_queue(s, 0xff);

        put_queue(s, 4); // Type 4

        put_queue(s, 0x7f);

        break;

    case 0xe: // Set leds

        s->led_mode = 1;

        break;

    case 7: // Query layout

    case 0xf:

        clear_queue(s);

        put_queue(s, 0xfe);

        put_queue(s, 0); // XXX, layout?