Commit 87a34e2a authored by Laurent Vivier's avatar Laurent Vivier
Browse files

hw/m68k: implement ADB bus support for via 



VIA needs to be able to poll the ADB interface and to read/write data
from/to the bus.

This patch adds functions allowing that.

Co-developed-by: default avatarMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: default avatarMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: default avatarLaurent Vivier <laurent@vivier.eu>
Reviewed-by: default avatarHervé Poussineau <hpoussin@reactos.org>
Reviewed-by: default avatarThomas Huth <huth@tuxfamily.org>
Message-Id: <20191026164546.30020-7-laurent@vivier.eu>
parent 6dca62a0

hw/misc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -123,5 +123,6 @@ config UNIMP 
config MAC_VIA

    bool

    select MOS6522

    select ADB



source macio/Kconfig

hw/misc/mac_via.c

+197 −0
Original line number Diff line number Diff line
@@ -264,10 +264,16 @@ 
 * Table 19-10 ADB transaction states

 */



#define ADB_STATE_NEW       0

#define ADB_STATE_EVEN      1

#define ADB_STATE_ODD       2

#define ADB_STATE_IDLE      3



#define VIA1B_vADB_StateMask    (VIA1B_vADBS1 | VIA1B_vADBS2)

#define VIA1B_vADB_StateShift   4



#define VIA_TIMER_FREQ (783360)

#define VIA_ADB_POLL_FREQ 50 /* XXX: not real */



/* VIA returns time offset from Jan 1, 1904, not 1970 */

#define RTC_OFFSET 2082844800
@@ -472,6 +478,181 @@ static void via1_rtc_update(MacVIAState *m) 
    }

}



static int adb_via_poll(MacVIAState *s, int state, uint8_t *data)

{

    if (state != ADB_STATE_IDLE) {

        return 0;

    }



    if (s->adb_data_in_size < s->adb_data_in_index) {

        return 0;

    }



    if (s->adb_data_out_index != 0) {

        return 0;

    }



    s->adb_data_in_index = 0;

    s->adb_data_out_index = 0;

    s->adb_data_in_size = adb_poll(&s->adb_bus, s->adb_data_in, 0xffff);



    if (s->adb_data_in_size) {

        *data = s->adb_data_in[s->adb_data_in_index++];

        qemu_irq_raise(s->adb_data_ready);

    }



    return s->adb_data_in_size;

}



static int adb_via_send(MacVIAState *s, int state, uint8_t data)

{

    switch (state) {

    case ADB_STATE_NEW:

        s->adb_data_out_index = 0;

        break;

    case ADB_STATE_EVEN:

        if ((s->adb_data_out_index & 1) == 0) {

            return 0;

        }

        break;

    case ADB_STATE_ODD:

        if (s->adb_data_out_index & 1) {

            return 0;

        }

        break;

    case ADB_STATE_IDLE:

        return 0;

    }



    assert(s->adb_data_out_index < sizeof(s->adb_data_out) - 1);



    s->adb_data_out[s->adb_data_out_index++] = data;

    qemu_irq_raise(s->adb_data_ready);

    return 1;

}



static int adb_via_receive(MacVIAState *s, int state, uint8_t *data)

{

    switch (state) {

    case ADB_STATE_NEW:

        return 0;



    case ADB_STATE_EVEN:

        if (s->adb_data_in_size <= 0) {

            qemu_irq_raise(s->adb_data_ready);

            return 0;

        }



        if (s->adb_data_in_index >= s->adb_data_in_size) {

            *data = 0;

            qemu_irq_raise(s->adb_data_ready);

            return 1;

        }



        if ((s->adb_data_in_index & 1) == 0) {

            return 0;

        }



        break;



    case ADB_STATE_ODD:

        if (s->adb_data_in_size <= 0) {

            qemu_irq_raise(s->adb_data_ready);

            return 0;

        }



        if (s->adb_data_in_index >= s->adb_data_in_size) {

            *data = 0;

            qemu_irq_raise(s->adb_data_ready);

            return 1;

        }



        if (s->adb_data_in_index & 1) {

            return 0;

        }



        break;



    case ADB_STATE_IDLE:

        if (s->adb_data_out_index == 0) {

            return 0;

        }



        s->adb_data_in_size = adb_request(&s->adb_bus, s->adb_data_in,

                                          s->adb_data_out,

                                          s->adb_data_out_index);

        s->adb_data_out_index = 0;

        s->adb_data_in_index = 0;

        if (s->adb_data_in_size < 0) {

            *data = 0xff;

            qemu_irq_raise(s->adb_data_ready);

            return -1;

        }



        if (s->adb_data_in_size == 0) {

            return 0;

        }



        break;

    }



    assert(s->adb_data_in_index < sizeof(s->adb_data_in) - 1);



    *data = s->adb_data_in[s->adb_data_in_index++];

    qemu_irq_raise(s->adb_data_ready);

    if (*data == 0xff || *data == 0) {

        return 0;

    }

    return 1;

}



static void via1_adb_update(MacVIAState *m)

{

    MOS6522Q800VIA1State *v1s = MOS6522_Q800_VIA1(&m->mos6522_via1);

    MOS6522State *s = MOS6522(v1s);

    int state;

    int ret;



    state = (s->b & VIA1B_vADB_StateMask) >> VIA1B_vADB_StateShift;



    if (s->acr & VIA1ACR_vShiftOut) {

        /* output mode */

        ret = adb_via_send(m, state, s->sr);

        if (ret > 0) {

            s->b &= ~VIA1B_vADBInt;

        } else {

            s->b |= VIA1B_vADBInt;

        }

    } else {

        /* input mode */

        ret = adb_via_receive(m, state, &s->sr);

        if (ret > 0 && s->sr != 0xff) {

            s->b &= ~VIA1B_vADBInt;

        } else {

            s->b |= VIA1B_vADBInt;

        }

    }

}



static void via_adb_poll(void *opaque)

{

    MacVIAState *m = opaque;

    MOS6522Q800VIA1State *v1s = MOS6522_Q800_VIA1(&m->mos6522_via1);

    MOS6522State *s = MOS6522(v1s);

    int state;



    if (s->b & VIA1B_vADBInt) {

        state = (s->b & VIA1B_vADB_StateMask) >> VIA1B_vADB_StateShift;

        if (adb_via_poll(m, state, &s->sr)) {

            s->b &= ~VIA1B_vADBInt;

        }

    }



    timer_mod(m->adb_poll_timer,

              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +

              (NANOSECONDS_PER_SECOND / VIA_ADB_POLL_FREQ));

}



static uint64_t mos6522_q800_via1_read(void *opaque, hwaddr addr, unsigned size)

{

    MOS6522Q800VIA1State *s = MOS6522_Q800_VIA1(opaque);
@@ -553,6 +734,10 @@ static void mac_via_reset(DeviceState *dev) 
    MacVIAState *m = MAC_VIA(dev);

    MOS6522Q800VIA1State *v1s = &m->mos6522_via1;



    timer_mod(m->adb_poll_timer,

              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +

              (NANOSECONDS_PER_SECOND / VIA_ADB_POLL_FREQ));



    timer_del(v1s->VBL_timer);

    v1s->next_VBL = 0;

    timer_del(v1s->one_second_timer);
@@ -593,6 +778,10 @@ static void mac_via_realize(DeviceState *dev, Error **errp) 


    qemu_get_timedate(&tm, 0);

    m->tick_offset = (uint32_t)mktimegm(&tm) + RTC_OFFSET;



    m->adb_poll_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, via_adb_poll, m);

    m->adb_data_ready = qdev_get_gpio_in_named(dev, "via1-irq",

                                               VIA1_IRQ_ADB_READY_BIT);

}



static void mac_via_init(Object *obj)
@@ -642,6 +831,13 @@ static const VMStateDescription vmstate_mac_via = { 
        VMSTATE_UINT8(cmd, MacVIAState),

        VMSTATE_INT32(wprotect, MacVIAState),

        VMSTATE_INT32(alt, MacVIAState),

        /* ADB */

        VMSTATE_TIMER_PTR(adb_poll_timer, MacVIAState),

        VMSTATE_INT32(adb_data_in_size, MacVIAState),

        VMSTATE_INT32(adb_data_in_index, MacVIAState),

        VMSTATE_INT32(adb_data_out_index, MacVIAState),

        VMSTATE_BUFFER(adb_data_in, MacVIAState),

        VMSTATE_BUFFER(adb_data_out, MacVIAState),

        VMSTATE_END_OF_LIST()

    }

};
@@ -671,6 +867,7 @@ static void mos6522_q800_via1_portB_write(MOS6522State *s) 
    MacVIAState *m = container_of(v1s, MacVIAState, mos6522_via1);



    via1_rtc_update(m);

    via1_adb_update(m);



    v1s->last_b = s->b;

}

include/hw/misc/mac_via.h

+7 −0
Original line number Diff line number Diff line
@@ -103,6 +103,13 @@ typedef struct MacVIAState { 


    /* ADB */

    ADBBusState adb_bus;

    QEMUTimer *adb_poll_timer;

    qemu_irq adb_data_ready;

    int adb_data_in_size;

    int adb_data_in_index;

    int adb_data_out_index;

    uint8_t adb_data_in[128];

    uint8_t adb_data_out[16];

} MacVIAState;



#endif