[qemu.git] / hw / char / mcf_uart.c

/*
 * ColdFire UART emulation.
 *
 * Copyright (c) 2007 CodeSourcery.
 *
 * This code is licensed under the GPL
 */
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/sysbus.h"
#include "hw/m68k/mcf.h"
#include "chardev/char-fe.h"

typedef struct {
    SysBusDevice parent_obj;

    MemoryRegion iomem;
    uint8_t mr[2];
    uint8_t sr;
    uint8_t isr;
    uint8_t imr;
    uint8_t bg1;
    uint8_t bg2;
    uint8_t fifo[4];
    uint8_t tb;
    int current_mr;
    int fifo_len;
    int tx_enabled;
    int rx_enabled;
    qemu_irq irq;
    CharBackend chr;
} mcf_uart_state;

#define TYPE_MCF_UART "mcf-uart"
#define MCF_UART(obj) OBJECT_CHECK(mcf_uart_state, (obj), TYPE_MCF_UART)

/* UART Status Register bits.  */
#define MCF_UART_RxRDY  0x01
#define MCF_UART_FFULL  0x02
#define MCF_UART_TxRDY  0x04
#define MCF_UART_TxEMP  0x08
#define MCF_UART_OE     0x10
#define MCF_UART_PE     0x20
#define MCF_UART_FE     0x40
#define MCF_UART_RB     0x80

/* Interrupt flags.  */
#define MCF_UART_TxINT  0x01
#define MCF_UART_RxINT  0x02
#define MCF_UART_DBINT  0x04
#define MCF_UART_COSINT 0x80

/* UMR1 flags.  */
#define MCF_UART_BC0    0x01
#define MCF_UART_BC1    0x02
#define MCF_UART_PT     0x04
#define MCF_UART_PM0    0x08
#define MCF_UART_PM1    0x10
#define MCF_UART_ERR    0x20
#define MCF_UART_RxIRQ  0x40
#define MCF_UART_RxRTS  0x80

static void mcf_uart_update(mcf_uart_state *s)
{
    s->isr &= ~(MCF_UART_TxINT | MCF_UART_RxINT);
    if (s->sr & MCF_UART_TxRDY)
        s->isr |= MCF_UART_TxINT;
    if ((s->sr & ((s->mr[0] & MCF_UART_RxIRQ)
                  ? MCF_UART_FFULL : MCF_UART_RxRDY)) != 0)
        s->isr |= MCF_UART_RxINT;

    qemu_set_irq(s->irq, (s->isr & s->imr) != 0);
}

uint64_t mcf_uart_read(void *opaque, hwaddr addr,
                       unsigned size)
{
    mcf_uart_state *s = (mcf_uart_state *)opaque;
    switch (addr & 0x3f) {
    case 0x00:
        return s->mr[s->current_mr];
    case 0x04:
        return s->sr;
    case 0x0c:
        {
            uint8_t val;
            int i;

            if (s->fifo_len == 0)
                return 0;

            val = s->fifo[0];
            s->fifo_len--;
            for (i = 0; i < s->fifo_len; i++)
                s->fifo[i] = s->fifo[i + 1];
            s->sr &= ~MCF_UART_FFULL;
            if (s->fifo_len == 0)
                s->sr &= ~MCF_UART_RxRDY;
            mcf_uart_update(s);
            qemu_chr_fe_accept_input(&s->chr);
            return val;
        }
    case 0x10:
        /* TODO: Implement IPCR.  */
        return 0;
    case 0x14:
        return s->isr;
    case 0x18:
        return s->bg1;
    case 0x1c:
        return s->bg2;
    default:
        return 0;
    }
}

/* Update TxRDY flag and set data if present and enabled.  */
static void mcf_uart_do_tx(mcf_uart_state *s)
{
    if (s->tx_enabled && (s->sr & MCF_UART_TxEMP) == 0) {
        /* XXX this blocks entire thread. Rewrite to use
         * qemu_chr_fe_write and background I/O callbacks */
        qemu_chr_fe_write_all(&s->chr, (unsigned char *)&s->tb, 1);
        s->sr |= MCF_UART_TxEMP;
    }
    if (s->tx_enabled) {
        s->sr |= MCF_UART_TxRDY;
    } else {
        s->sr &= ~MCF_UART_TxRDY;
    }
}

static void mcf_do_command(mcf_uart_state *s, uint8_t cmd)
{
    /* Misc command.  */
    switch ((cmd >> 4) & 7) {
    case 0: /* No-op.  */
        break;
    case 1: /* Reset mode register pointer.  */
        s->current_mr = 0;
        break;
    case 2: /* Reset receiver.  */
        s->rx_enabled = 0;
        s->fifo_len = 0;
        s->sr &= ~(MCF_UART_RxRDY | MCF_UART_FFULL);
        break;
    case 3: /* Reset transmitter.  */
        s->tx_enabled = 0;
        s->sr |= MCF_UART_TxEMP;
        s->sr &= ~MCF_UART_TxRDY;
        break;
    case 4: /* Reset error status.  */
        break;
    case 5: /* Reset break-change interrupt.  */
        s->isr &= ~MCF_UART_DBINT;
        break;
    case 6: /* Start break.  */
    case 7: /* Stop break.  */
        break;
    }

    /* Transmitter command.  */
    switch ((cmd >> 2) & 3) {
    case 0: /* No-op.  */
        break;
    case 1: /* Enable.  */
        s->tx_enabled = 1;
        mcf_uart_do_tx(s);
        break;
    case 2: /* Disable.  */
        s->tx_enabled = 0;
        mcf_uart_do_tx(s);
        break;
    case 3: /* Reserved.  */
        fprintf(stderr, "mcf_uart: Bad TX command\n");
        break;
    }

    /* Receiver command.  */
    switch (cmd & 3) {
    case 0: /* No-op.  */
        break;
    case 1: /* Enable.  */
        s->rx_enabled = 1;
        break;
    case 2:
        s->rx_enabled = 0;
        break;
    case 3: /* Reserved.  */
        fprintf(stderr, "mcf_uart: Bad RX command\n");
        break;
    }
}

void mcf_uart_write(void *opaque, hwaddr addr,
                    uint64_t val, unsigned size)
{
    mcf_uart_state *s = (mcf_uart_state *)opaque;
    switch (addr & 0x3f) {
    case 0x00:
        s->mr[s->current_mr] = val;
        s->current_mr = 1;
        break;
    case 0x04:
        /* CSR is ignored.  */
        break;
    case 0x08: /* Command Register.  */
        mcf_do_command(s, val);
        break;
    case 0x0c: /* Transmit Buffer.  */
        s->sr &= ~MCF_UART_TxEMP;
        s->tb = val;
        mcf_uart_do_tx(s);
        break;
    case 0x10:
        /* ACR is ignored.  */
        break;
    case 0x14:
        s->imr = val;
        break;
    default:
        break;
    }
    mcf_uart_update(s);
}

static void mcf_uart_reset(DeviceState *dev)
{
    mcf_uart_state *s = MCF_UART(dev);

    s->fifo_len = 0;
    s->mr[0] = 0;
    s->mr[1] = 0;
    s->sr = MCF_UART_TxEMP;
    s->tx_enabled = 0;
    s->rx_enabled = 0;
    s->isr = 0;
    s->imr = 0;
}

static void mcf_uart_push_byte(mcf_uart_state *s, uint8_t data)
{
    /* Break events overwrite the last byte if the fifo is full.  */
    if (s->fifo_len == 4)
        s->fifo_len--;

    s->fifo[s->fifo_len] = data;
    s->fifo_len++;
    s->sr |= MCF_UART_RxRDY;
    if (s->fifo_len == 4)
        s->sr |= MCF_UART_FFULL;

    mcf_uart_update(s);
}

static void mcf_uart_event(void *opaque, int event)
{
    mcf_uart_state *s = (mcf_uart_state *)opaque;

    switch (event) {
    case CHR_EVENT_BREAK:
        s->isr |= MCF_UART_DBINT;
        mcf_uart_push_byte(s, 0);
        break;
    default:
        break;
    }
}

static int mcf_uart_can_receive(void *opaque)
{
    mcf_uart_state *s = (mcf_uart_state *)opaque;

    return s->rx_enabled && (s->sr & MCF_UART_FFULL) == 0;
}

static void mcf_uart_receive(void *opaque, const uint8_t *buf, int size)
{
    mcf_uart_state *s = (mcf_uart_state *)opaque;

    mcf_uart_push_byte(s, buf[0]);
}

static const MemoryRegionOps mcf_uart_ops = {
    .read = mcf_uart_read,
    .write = mcf_uart_write,
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static void mcf_uart_instance_init(Object *obj)
{
    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
    mcf_uart_state *s = MCF_UART(dev);

    memory_region_init_io(&s->iomem, obj, &mcf_uart_ops, s, "uart", 0x40);
    sysbus_init_mmio(dev, &s->iomem);

    sysbus_init_irq(dev, &s->irq);
}

static void mcf_uart_realize(DeviceState *dev, Error **errp)
{
    mcf_uart_state *s = MCF_UART(dev);

    qemu_chr_fe_set_handlers(&s->chr, mcf_uart_can_receive, mcf_uart_receive,
                             mcf_uart_event, NULL, s, NULL, true);
}

static Property mcf_uart_properties[] = {
    DEFINE_PROP_CHR("chardev", mcf_uart_state, chr),
    DEFINE_PROP_END_OF_LIST(),
};

static void mcf_uart_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    dc->realize = mcf_uart_realize;
    dc->reset = mcf_uart_reset;
    dc->props = mcf_uart_properties;
    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
}

static const TypeInfo mcf_uart_info = {
    .name          = TYPE_MCF_UART,
    .parent        = TYPE_SYS_BUS_DEVICE,
    .instance_size = sizeof(mcf_uart_state),
    .instance_init = mcf_uart_instance_init,
    .class_init    = mcf_uart_class_init,
};

static void mcf_uart_register(void)
{
    type_register_static(&mcf_uart_info);
}

type_init(mcf_uart_register)

void *mcf_uart_init(qemu_irq irq, Chardev *chrdrv)
{
    DeviceState  *dev;

    dev = qdev_create(NULL, TYPE_MCF_UART);
    if (chrdrv) {
        qdev_prop_set_chr(dev, "chardev", chrdrv);
    }
    qdev_init_nofail(dev);

    sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);

    return dev;
}

void mcf_uart_mm_init(hwaddr base, qemu_irq irq, Chardev *chrdrv)
{
    DeviceState  *dev;

    dev = mcf_uart_init(irq, chrdrv);
    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
}
Commit	Line	Data
5fafdf24	1	/*
20dcee94 PB	2	* ColdFire UART emulation.
	3	*
	4	* Copyright (c) 2007 CodeSourcery.
	5	*
8e31bf38	6	* This code is licensed under the GPL
20dcee94	7	*/
0430891c	8	#include "qemu/osdep.h"
83c9f4ca	9	#include "hw/hw.h"
d9ff1d35	10	#include "hw/sysbus.h"
0d09e41a	11	#include "hw/m68k/mcf.h"
4d43a603	12	#include "chardev/char-fe.h"
20dcee94 PB	13
20dcee94 PB	14	typedef struct {
d9ff1d35 TH	15	SysBusDevice parent_obj;
d9ff1d35 TH	16
aa6e4986	17	MemoryRegion iomem;
20dcee94 PB	18	uint8_t mr[2];
	19	uint8_t sr;
	20	uint8_t isr;
	21	uint8_t imr;
	22	uint8_t bg1;
	23	uint8_t bg2;
	24	uint8_t fifo[4];
	25	uint8_t tb;
	26	int current_mr;
	27	int fifo_len;
	28	int tx_enabled;
	29	int rx_enabled;
	30	qemu_irq irq;
32a6ebec	31	CharBackend chr;
20dcee94 PB	32	} mcf_uart_state;
20dcee94 PB	33
d9ff1d35 TH	34	#define TYPE_MCF_UART "mcf-uart"
	35	#define MCF_UART(obj) OBJECT_CHECK(mcf_uart_state, (obj), TYPE_MCF_UART)
	36
20dcee94 PB	37	/* UART Status Register bits. */
	38	#define MCF_UART_RxRDY 0x01
	39	#define MCF_UART_FFULL 0x02
	40	#define MCF_UART_TxRDY 0x04
	41	#define MCF_UART_TxEMP 0x08
	42	#define MCF_UART_OE 0x10
	43	#define MCF_UART_PE 0x20
	44	#define MCF_UART_FE 0x40
	45	#define MCF_UART_RB 0x80
	46
	47	/* Interrupt flags. */
	48	#define MCF_UART_TxINT 0x01
	49	#define MCF_UART_RxINT 0x02
	50	#define MCF_UART_DBINT 0x04
	51	#define MCF_UART_COSINT 0x80
	52
	53	/* UMR1 flags. */
	54	#define MCF_UART_BC0 0x01
	55	#define MCF_UART_BC1 0x02
	56	#define MCF_UART_PT 0x04
	57	#define MCF_UART_PM0 0x08
	58	#define MCF_UART_PM1 0x10
	59	#define MCF_UART_ERR 0x20
	60	#define MCF_UART_RxIRQ 0x40
	61	#define MCF_UART_RxRTS 0x80
	62
	63	static void mcf_uart_update(mcf_uart_state *s)
	64	{
	65	s->isr &= ~(MCF_UART_TxINT \| MCF_UART_RxINT);
	66	if (s->sr & MCF_UART_TxRDY)
	67	s->isr \|= MCF_UART_TxINT;
	68	if ((s->sr & ((s->mr[0] & MCF_UART_RxIRQ)
	69	? MCF_UART_FFULL : MCF_UART_RxRDY)) != 0)
	70	s->isr \|= MCF_UART_RxINT;
	71
	72	qemu_set_irq(s->irq, (s->isr & s->imr) != 0);
	73	}
	74
a8170e5e	75	uint64_t mcf_uart_read(void *opaque, hwaddr addr,
aa6e4986	76	unsigned size)
20dcee94 PB	77	{
	78	mcf_uart_state s = (mcf_uart_state )opaque;
	79	switch (addr & 0x3f) {
	80	case 0x00:
	81	return s->mr[s->current_mr];
	82	case 0x04:
	83	return s->sr;
	84	case 0x0c:
	85	{
	86	uint8_t val;
	87	int i;
	88
	89	if (s->fifo_len == 0)
	90	return 0;
	91
	92	val = s->fifo[0];
	93	s->fifo_len--;
	94	for (i = 0; i < s->fifo_len; i++)
	95	s->fifo[i] = s->fifo[i + 1];
	96	s->sr &= ~MCF_UART_FFULL;
	97	if (s->fifo_len == 0)
	98	s->sr &= ~MCF_UART_RxRDY;
	99	mcf_uart_update(s);
5345fdb4	100	qemu_chr_fe_accept_input(&s->chr);
20dcee94 PB	101	return val;
	102	}
	103	case 0x10:
	104	/* TODO: Implement IPCR. */
	105	return 0;
	106	case 0x14:
	107	return s->isr;
	108	case 0x18:
	109	return s->bg1;
	110	case 0x1c:
	111	return s->bg2;
	112	default:
	113	return 0;
	114	}
	115	}
	116
	117	/* Update TxRDY flag and set data if present and enabled. */
	118	static void mcf_uart_do_tx(mcf_uart_state *s)
	119	{
	120	if (s->tx_enabled && (s->sr & MCF_UART_TxEMP) == 0) {
fa394ed6 MAL	121	/* XXX this blocks entire thread. Rewrite to use
	122	* qemu_chr_fe_write and background I/O callbacks */
	123	qemu_chr_fe_write_all(&s->chr, (unsigned char *)&s->tb, 1);
20dcee94 PB	124	s->sr \|= MCF_UART_TxEMP;
	125	}
	126	if (s->tx_enabled) {
	127	s->sr \|= MCF_UART_TxRDY;
	128	} else {
	129	s->sr &= ~MCF_UART_TxRDY;
	130	}
	131	}
	132
	133	static void mcf_do_command(mcf_uart_state *s, uint8_t cmd)
	134	{
	135	/* Misc command. */
491ffc1f	136	switch ((cmd >> 4) & 7) {
20dcee94 PB	137	case 0: /* No-op. */
	138	break;
	139	case 1: /* Reset mode register pointer. */
	140	s->current_mr = 0;
	141	break;
	142	case 2: /* Reset receiver. */
	143	s->rx_enabled = 0;
	144	s->fifo_len = 0;
	145	s->sr &= ~(MCF_UART_RxRDY \| MCF_UART_FFULL);
	146	break;
	147	case 3: /* Reset transmitter. */
	148	s->tx_enabled = 0;
	149	s->sr \|= MCF_UART_TxEMP;
	150	s->sr &= ~MCF_UART_TxRDY;
	151	break;
	152	case 4: /* Reset error status. */
	153	break;
	154	case 5: /* Reset break-change interrupt. */
	155	s->isr &= ~MCF_UART_DBINT;
	156	break;
	157	case 6: /* Start break. */
	158	case 7: /* Stop break. */
	159	break;
	160	}
	161
	162	/* Transmitter command. */
	163	switch ((cmd >> 2) & 3) {
	164	case 0: /* No-op. */
	165	break;
	166	case 1: /* Enable. */
	167	s->tx_enabled = 1;
	168	mcf_uart_do_tx(s);
	169	break;
	170	case 2: /* Disable. */
	171	s->tx_enabled = 0;
	172	mcf_uart_do_tx(s);
	173	break;
	174	case 3: /* Reserved. */
	175	fprintf(stderr, "mcf_uart: Bad TX command\n");
	176	break;
	177	}
	178
	179	/* Receiver command. */
	180	switch (cmd & 3) {
	181	case 0: /* No-op. */
	182	break;
	183	case 1: /* Enable. */
	184	s->rx_enabled = 1;
	185	break;
	186	case 2:
	187	s->rx_enabled = 0;
	188	break;
	189	case 3: /* Reserved. */
	190	fprintf(stderr, "mcf_uart: Bad RX command\n");
	191	break;
	192	}
	193	}
	194
a8170e5e	195	void mcf_uart_write(void *opaque, hwaddr addr,
aa6e4986	196	uint64_t val, unsigned size)
20dcee94 PB	197	{
	198	mcf_uart_state s = (mcf_uart_state )opaque;
	199	switch (addr & 0x3f) {
	200	case 0x00:
	201	s->mr[s->current_mr] = val;
	202	s->current_mr = 1;
	203	break;
	204	case 0x04:
	205	/* CSR is ignored. */
	206	break;
	207	case 0x08: /* Command Register. */
	208	mcf_do_command(s, val);
	209	break;
	210	case 0x0c: /* Transmit Buffer. */
	211	s->sr &= ~MCF_UART_TxEMP;
	212	s->tb = val;
	213	mcf_uart_do_tx(s);
	214	break;
	215	case 0x10:
	216	/* ACR is ignored. */
	217	break;
	218	case 0x14:
	219	s->imr = val;
	220	break;
	221	default:
	222	break;
	223	}
	224	mcf_uart_update(s);
	225	}
	226
d9ff1d35	227	static void mcf_uart_reset(DeviceState *dev)
20dcee94	228	{
d9ff1d35 TH	229	mcf_uart_state *s = MCF_UART(dev);
d9ff1d35 TH	230
20dcee94 PB	231	s->fifo_len = 0;
	232	s->mr[0] = 0;
	233	s->mr[1] = 0;
	234	s->sr = MCF_UART_TxEMP;
	235	s->tx_enabled = 0;
	236	s->rx_enabled = 0;
	237	s->isr = 0;
	238	s->imr = 0;
	239	}
	240
	241	static void mcf_uart_push_byte(mcf_uart_state *s, uint8_t data)
	242	{
	243	/* Break events overwrite the last byte if the fifo is full. */
	244	if (s->fifo_len == 4)
	245	s->fifo_len--;
	246
	247	s->fifo[s->fifo_len] = data;
	248	s->fifo_len++;
	249	s->sr \|= MCF_UART_RxRDY;
	250	if (s->fifo_len == 4)
	251	s->sr \|= MCF_UART_FFULL;
	252
	253	mcf_uart_update(s);
	254	}
	255
	256	static void mcf_uart_event(void *opaque, int event)
	257	{
	258	mcf_uart_state s = (mcf_uart_state )opaque;
	259
	260	switch (event) {
	261	case CHR_EVENT_BREAK:
	262	s->isr \|= MCF_UART_DBINT;
	263	mcf_uart_push_byte(s, 0);
	264	break;
	265	default:
	266	break;
	267	}
	268	}
	269
	270	static int mcf_uart_can_receive(void *opaque)
	271	{
	272	mcf_uart_state s = (mcf_uart_state )opaque;
	273
	274	return s->rx_enabled && (s->sr & MCF_UART_FFULL) == 0;
	275	}
	276
	277	static void mcf_uart_receive(void opaque, const uint8_t buf, int size)
	278	{
	279	mcf_uart_state s = (mcf_uart_state )opaque;
	280
	281	mcf_uart_push_byte(s, buf[0]);
	282	}
	283
aa6e4986 BC	284	static const MemoryRegionOps mcf_uart_ops = {
	285	.read = mcf_uart_read,
	286	.write = mcf_uart_write,
	287	.endianness = DEVICE_NATIVE_ENDIAN,
20dcee94 PB	288	};
20dcee94 PB	289
d9ff1d35 TH	290	static void mcf_uart_instance_init(Object *obj)
	291	{
	292	SysBusDevice *dev = SYS_BUS_DEVICE(obj);
	293	mcf_uart_state *s = MCF_UART(dev);
	294
	295	memory_region_init_io(&s->iomem, obj, &mcf_uart_ops, s, "uart", 0x40);
	296	sysbus_init_mmio(dev, &s->iomem);
	297
	298	sysbus_init_irq(dev, &s->irq);
	299	}
	300
	301	static void mcf_uart_realize(DeviceState dev, Error *errp)
	302	{
	303	mcf_uart_state *s = MCF_UART(dev);
	304
	305	qemu_chr_fe_set_handlers(&s->chr, mcf_uart_can_receive, mcf_uart_receive,
81517ba3	306	mcf_uart_event, NULL, s, NULL, true);
d9ff1d35 TH	307	}
	308
	309	static Property mcf_uart_properties[] = {
	310	DEFINE_PROP_CHR("chardev", mcf_uart_state, chr),
	311	DEFINE_PROP_END_OF_LIST(),
	312	};
	313
	314	static void mcf_uart_class_init(ObjectClass oc, void data)
	315	{
	316	DeviceClass *dc = DEVICE_CLASS(oc);
	317
	318	dc->realize = mcf_uart_realize;
	319	dc->reset = mcf_uart_reset;
	320	dc->props = mcf_uart_properties;
	321	set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
	322	}
	323
	324	static const TypeInfo mcf_uart_info = {
	325	.name = TYPE_MCF_UART,
	326	.parent = TYPE_SYS_BUS_DEVICE,
	327	.instance_size = sizeof(mcf_uart_state),
	328	.instance_init = mcf_uart_instance_init,
	329	.class_init = mcf_uart_class_init,
	330	};
	331
	332	static void mcf_uart_register(void)
	333	{
	334	type_register_static(&mcf_uart_info);
	335	}
	336
	337	type_init(mcf_uart_register)
	338
	339	void mcf_uart_init(qemu_irq irq, Chardev chrdrv)
	340	{
	341	DeviceState *dev;
	342
	343	dev = qdev_create(NULL, TYPE_MCF_UART);
	344	if (chrdrv) {
	345	qdev_prop_set_chr(dev, "chardev", chrdrv);
	346	}
	347	qdev_init_nofail(dev);
	348
	349	sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);
	350
	351	return dev;
	352	}
	353
	354	void mcf_uart_mm_init(hwaddr base, qemu_irq irq, Chardev *chrdrv)
20dcee94	355	{
d9ff1d35	356	DeviceState *dev;
20dcee94	357
d9ff1d35 TH	358	dev = mcf_uart_init(irq, chrdrv);
d9ff1d35 TH	359	sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
20dcee94	360	}