[qemu.git] / hw / pl011.c

/*
 * Arm PrimeCell PL011 UART
 *
 * Copyright (c) 2006 CodeSourcery.
 * Written by Paul Brook
 *
 * This code is licensed under the GPL.
 */

#include "sysbus.h"
#include "qemu-char.h"

typedef struct {
    SysBusDevice busdev;
    uint32_t readbuff;
    uint32_t flags;
    uint32_t lcr;
    uint32_t cr;
    uint32_t dmacr;
    uint32_t int_enabled;
    uint32_t int_level;
    uint32_t read_fifo[16];
    uint32_t ilpr;
    uint32_t ibrd;
    uint32_t fbrd;
    uint32_t ifl;
    int read_pos;
    int read_count;
    int read_trigger;
    CharDriverState *chr;
    qemu_irq irq;
    const unsigned char *id;
} pl011_state;

#define PL011_INT_TX 0x20
#define PL011_INT_RX 0x10

#define PL011_FLAG_TXFE 0x80
#define PL011_FLAG_RXFF 0x40
#define PL011_FLAG_TXFF 0x20
#define PL011_FLAG_RXFE 0x10

static const unsigned char pl011_id_arm[8] =
  { 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
static const unsigned char pl011_id_luminary[8] =
  { 0x11, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };

static void pl011_update(pl011_state *s)
{
    uint32_t flags;

    flags = s->int_level & s->int_enabled;
    qemu_set_irq(s->irq, flags != 0);
}

static uint32_t pl011_read(void *opaque, target_phys_addr_t offset)
{
    pl011_state *s = (pl011_state *)opaque;
    uint32_t c;

    if (offset >= 0xfe0 && offset < 0x1000) {
        return s->id[(offset - 0xfe0) >> 2];
    }
    switch (offset >> 2) {
    case 0: /* UARTDR */
        s->flags &= ~PL011_FLAG_RXFF;
        c = s->read_fifo[s->read_pos];
        if (s->read_count > 0) {
            s->read_count--;
            if (++s->read_pos == 16)
                s->read_pos = 0;
        }
        if (s->read_count == 0) {
            s->flags |= PL011_FLAG_RXFE;
        }
        if (s->read_count == s->read_trigger - 1)
            s->int_level &= ~ PL011_INT_RX;
        pl011_update(s);
        qemu_chr_accept_input(s->chr);
        return c;
    case 1: /* UARTCR */
        return 0;
    case 6: /* UARTFR */
        return s->flags;
    case 8: /* UARTILPR */
        return s->ilpr;
    case 9: /* UARTIBRD */
        return s->ibrd;
    case 10: /* UARTFBRD */
        return s->fbrd;
    case 11: /* UARTLCR_H */
        return s->lcr;
    case 12: /* UARTCR */
        return s->cr;
    case 13: /* UARTIFLS */
        return s->ifl;
    case 14: /* UARTIMSC */
        return s->int_enabled;
    case 15: /* UARTRIS */
        return s->int_level;
    case 16: /* UARTMIS */
        return s->int_level & s->int_enabled;
    case 18: /* UARTDMACR */
        return s->dmacr;
    default:
        hw_error("pl011_read: Bad offset %x\n", (int)offset);
        return 0;
    }
}

static void pl011_set_read_trigger(pl011_state *s)
{
#if 0
    /* The docs say the RX interrupt is triggered when the FIFO exceeds
       the threshold.  However linux only reads the FIFO in response to an
       interrupt.  Triggering the interrupt when the FIFO is non-empty seems
       to make things work.  */
    if (s->lcr & 0x10)
        s->read_trigger = (s->ifl >> 1) & 0x1c;
    else
#endif
        s->read_trigger = 1;
}

static void pl011_write(void *opaque, target_phys_addr_t offset,
                          uint32_t value)
{
    pl011_state *s = (pl011_state *)opaque;
    unsigned char ch;

    switch (offset >> 2) {
    case 0: /* UARTDR */
        /* ??? Check if transmitter is enabled.  */
        ch = value;
        if (s->chr)
            qemu_chr_write(s->chr, &ch, 1);
        s->int_level |= PL011_INT_TX;
        pl011_update(s);
        break;
    case 1: /* UARTCR */
        s->cr = value;
        break;
    case 6: /* UARTFR */
        /* Writes to Flag register are ignored.  */
        break;
    case 8: /* UARTUARTILPR */
        s->ilpr = value;
        break;
    case 9: /* UARTIBRD */
        s->ibrd = value;
        break;
    case 10: /* UARTFBRD */
        s->fbrd = value;
        break;
    case 11: /* UARTLCR_H */
        s->lcr = value;
        pl011_set_read_trigger(s);
        break;
    case 12: /* UARTCR */
        /* ??? Need to implement the enable and loopback bits.  */
        s->cr = value;
        break;
    case 13: /* UARTIFS */
        s->ifl = value;
        pl011_set_read_trigger(s);
        break;
    case 14: /* UARTIMSC */
        s->int_enabled = value;
        pl011_update(s);
        break;
    case 17: /* UARTICR */
        s->int_level &= ~value;
        pl011_update(s);
        break;
    case 18: /* UARTDMACR */
        s->dmacr = value;
        if (value & 3)
            hw_error("PL011: DMA not implemented\n");
        break;
    default:
        hw_error("pl011_write: Bad offset %x\n", (int)offset);
    }
}

static int pl011_can_receive(void *opaque)
{
    pl011_state *s = (pl011_state *)opaque;

    if (s->lcr & 0x10)
        return s->read_count < 16;
    else
        return s->read_count < 1;
}

static void pl011_put_fifo(void *opaque, uint32_t value)
{
    pl011_state *s = (pl011_state *)opaque;
    int slot;

    slot = s->read_pos + s->read_count;
    if (slot >= 16)
        slot -= 16;
    s->read_fifo[slot] = value;
    s->read_count++;
    s->flags &= ~PL011_FLAG_RXFE;
    if (s->cr & 0x10 || s->read_count == 16) {
        s->flags |= PL011_FLAG_RXFF;
    }
    if (s->read_count == s->read_trigger) {
        s->int_level |= PL011_INT_RX;
        pl011_update(s);
    }
}

static void pl011_receive(void *opaque, const uint8_t *buf, int size)
{
    pl011_put_fifo(opaque, *buf);
}

static void pl011_event(void *opaque, int event)
{
    if (event == CHR_EVENT_BREAK)
        pl011_put_fifo(opaque, 0x400);
}

static CPUReadMemoryFunc * const pl011_readfn[] = {
   pl011_read,
   pl011_read,
   pl011_read
};

static CPUWriteMemoryFunc * const pl011_writefn[] = {
   pl011_write,
   pl011_write,
   pl011_write
};

static const VMStateDescription vmstate_pl011 = {
    .name = "pl011",
    .version_id = 1,
    .minimum_version_id = 1,
    .minimum_version_id_old = 1,
    .fields      = (VMStateField[]) {
        VMSTATE_UINT32(readbuff, pl011_state),
        VMSTATE_UINT32(flags, pl011_state),
        VMSTATE_UINT32(lcr, pl011_state),
        VMSTATE_UINT32(cr, pl011_state),
        VMSTATE_UINT32(dmacr, pl011_state),
        VMSTATE_UINT32(int_enabled, pl011_state),
        VMSTATE_UINT32(int_level, pl011_state),
        VMSTATE_UINT32_ARRAY(read_fifo, pl011_state, 16),
        VMSTATE_UINT32(ilpr, pl011_state),
        VMSTATE_UINT32(ibrd, pl011_state),
        VMSTATE_UINT32(fbrd, pl011_state),
        VMSTATE_UINT32(ifl, pl011_state),
        VMSTATE_INT32(read_pos, pl011_state),
        VMSTATE_INT32(read_count, pl011_state),
        VMSTATE_INT32(read_trigger, pl011_state),
        VMSTATE_END_OF_LIST()
    }
};

static int pl011_init(SysBusDevice *dev, const unsigned char *id)
{
    int iomemtype;
    pl011_state *s = FROM_SYSBUS(pl011_state, dev);

    iomemtype = cpu_register_io_memory(pl011_readfn,
                                       pl011_writefn, s,
                                       DEVICE_NATIVE_ENDIAN);
    sysbus_init_mmio(dev, 0x1000,iomemtype);
    sysbus_init_irq(dev, &s->irq);
    s->id = id;
    s->chr = qdev_init_chardev(&dev->qdev);

    s->read_trigger = 1;
    s->ifl = 0x12;
    s->cr = 0x300;
    s->flags = 0x90;
    if (s->chr) {
        qemu_chr_add_handlers(s->chr, pl011_can_receive, pl011_receive,
                              pl011_event, s);
    }
    vmstate_register(&dev->qdev, -1, &vmstate_pl011, s);
    return 0;
}

static int pl011_init_arm(SysBusDevice *dev)
{
    return pl011_init(dev, pl011_id_arm);
}

static int pl011_init_luminary(SysBusDevice *dev)
{
    return pl011_init(dev, pl011_id_luminary);
}

static void pl011_register_devices(void)
{
    sysbus_register_dev("pl011", sizeof(pl011_state),
                        pl011_init_arm);
    sysbus_register_dev("pl011_luminary", sizeof(pl011_state),
                        pl011_init_luminary);
}

device_init(pl011_register_devices)
Commit	Line	Data
5fafdf24	1	/*
cdbdb648 PB	2	* Arm PrimeCell PL011 UART
	3	*
	4	* Copyright (c) 2006 CodeSourcery.
	5	* Written by Paul Brook
	6	*
8e31bf38	7	* This code is licensed under the GPL.
cdbdb648 PB	8	*/
cdbdb648 PB	9
a7d518a6	10	#include "sysbus.h"
87ecb68b	11	#include "qemu-char.h"
cdbdb648 PB	12
cdbdb648 PB	13	typedef struct {
a7d518a6	14	SysBusDevice busdev;
cdbdb648 PB	15	uint32_t readbuff;
	16	uint32_t flags;
	17	uint32_t lcr;
	18	uint32_t cr;
	19	uint32_t dmacr;
	20	uint32_t int_enabled;
	21	uint32_t int_level;
	22	uint32_t read_fifo[16];
	23	uint32_t ilpr;
	24	uint32_t ibrd;
	25	uint32_t fbrd;
	26	uint32_t ifl;
	27	int read_pos;
	28	int read_count;
	29	int read_trigger;
	30	CharDriverState *chr;
d537cf6c	31	qemu_irq irq;
a7d518a6	32	const unsigned char *id;
cdbdb648 PB	33	} pl011_state;
	34
	35	#define PL011_INT_TX 0x20
	36	#define PL011_INT_RX 0x10
	37
	38	#define PL011_FLAG_TXFE 0x80
	39	#define PL011_FLAG_RXFF 0x40
	40	#define PL011_FLAG_TXFF 0x20
	41	#define PL011_FLAG_RXFE 0x10
	42
a7d518a6 PB	43	static const unsigned char pl011_id_arm[8] =
	44	{ 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
	45	static const unsigned char pl011_id_luminary[8] =
	46	{ 0x11, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };
cdbdb648 PB	47
	48	static void pl011_update(pl011_state *s)
	49	{
	50	uint32_t flags;
3b46e624	51
cdbdb648	52	flags = s->int_level & s->int_enabled;
d537cf6c	53	qemu_set_irq(s->irq, flags != 0);
cdbdb648 PB	54	}
cdbdb648 PB	55
c227f099	56	static uint32_t pl011_read(void *opaque, target_phys_addr_t offset)
cdbdb648 PB	57	{
	58	pl011_state s = (pl011_state )opaque;
	59	uint32_t c;
	60
cdbdb648	61	if (offset >= 0xfe0 && offset < 0x1000) {
a7d518a6	62	return s->id[(offset - 0xfe0) >> 2];
cdbdb648 PB	63	}
	64	switch (offset >> 2) {
	65	case 0: /* UARTDR */
	66	s->flags &= ~PL011_FLAG_RXFF;
	67	c = s->read_fifo[s->read_pos];
	68	if (s->read_count > 0) {
	69	s->read_count--;
	70	if (++s->read_pos == 16)
	71	s->read_pos = 0;
	72	}
	73	if (s->read_count == 0) {
	74	s->flags \|= PL011_FLAG_RXFE;
	75	}
	76	if (s->read_count == s->read_trigger - 1)
	77	s->int_level &= ~ PL011_INT_RX;
	78	pl011_update(s);
bd9bdce6	79	qemu_chr_accept_input(s->chr);
cdbdb648 PB	80	return c;
	81	case 1: /* UARTCR */
	82	return 0;
	83	case 6: /* UARTFR */
	84	return s->flags;
	85	case 8: /* UARTILPR */
	86	return s->ilpr;
	87	case 9: /* UARTIBRD */
	88	return s->ibrd;
	89	case 10: /* UARTFBRD */
	90	return s->fbrd;
	91	case 11: /* UARTLCR_H */
	92	return s->lcr;
	93	case 12: /* UARTCR */
	94	return s->cr;
	95	case 13: /* UARTIFLS */
	96	return s->ifl;
	97	case 14: /* UARTIMSC */
	98	return s->int_enabled;
	99	case 15: /* UARTRIS */
	100	return s->int_level;
	101	case 16: /* UARTMIS */
	102	return s->int_level & s->int_enabled;
	103	case 18: /* UARTDMACR */
	104	return s->dmacr;
	105	default:
2ac71179	106	hw_error("pl011_read: Bad offset %x\n", (int)offset);
cdbdb648 PB	107	return 0;
	108	}
	109	}
	110
	111	static void pl011_set_read_trigger(pl011_state *s)
	112	{
	113	#if 0
	114	/* The docs say the RX interrupt is triggered when the FIFO exceeds
	115	the threshold. However linux only reads the FIFO in response to an
	116	interrupt. Triggering the interrupt when the FIFO is non-empty seems
	117	to make things work. */
	118	if (s->lcr & 0x10)
	119	s->read_trigger = (s->ifl >> 1) & 0x1c;
	120	else
	121	#endif
	122	s->read_trigger = 1;
	123	}
	124
c227f099	125	static void pl011_write(void *opaque, target_phys_addr_t offset,
cdbdb648 PB	126	uint32_t value)
	127	{
	128	pl011_state s = (pl011_state )opaque;
	129	unsigned char ch;
	130
cdbdb648 PB	131	switch (offset >> 2) {
	132	case 0: /* UARTDR */
	133	/* ??? Check if transmitter is enabled. */
	134	ch = value;
	135	if (s->chr)
	136	qemu_chr_write(s->chr, &ch, 1);
	137	s->int_level \|= PL011_INT_TX;
	138	pl011_update(s);
	139	break;
	140	case 1: /* UARTCR */
	141	s->cr = value;
	142	break;
9ee6e8bb PB	143	case 6: /* UARTFR */
	144	/* Writes to Flag register are ignored. */
	145	break;
cdbdb648 PB	146	case 8: /* UARTUARTILPR */
	147	s->ilpr = value;
	148	break;
	149	case 9: /* UARTIBRD */
	150	s->ibrd = value;
	151	break;
	152	case 10: /* UARTFBRD */
	153	s->fbrd = value;
	154	break;
	155	case 11: /* UARTLCR_H */
	156	s->lcr = value;
	157	pl011_set_read_trigger(s);
	158	break;
	159	case 12: /* UARTCR */
	160	/* ??? Need to implement the enable and loopback bits. */
	161	s->cr = value;
	162	break;
	163	case 13: /* UARTIFS */
	164	s->ifl = value;
	165	pl011_set_read_trigger(s);
	166	break;
	167	case 14: /* UARTIMSC */
	168	s->int_enabled = value;
	169	pl011_update(s);
	170	break;
	171	case 17: /* UARTICR */
	172	s->int_level &= ~value;
	173	pl011_update(s);
	174	break;
	175	case 18: /* UARTDMACR */
	176	s->dmacr = value;
	177	if (value & 3)
2ac71179	178	hw_error("PL011: DMA not implemented\n");
cdbdb648 PB	179	break;
cdbdb648 PB	180	default:
2ac71179	181	hw_error("pl011_write: Bad offset %x\n", (int)offset);
cdbdb648 PB	182	}
	183	}
	184
aa1f17c1	185	static int pl011_can_receive(void *opaque)
cdbdb648 PB	186	{
	187	pl011_state s = (pl011_state )opaque;
	188
	189	if (s->lcr & 0x10)
	190	return s->read_count < 16;
	191	else
	192	return s->read_count < 1;
	193	}
	194
cc9c9ffc	195	static void pl011_put_fifo(void *opaque, uint32_t value)
cdbdb648 PB	196	{
	197	pl011_state s = (pl011_state )opaque;
	198	int slot;
	199
	200	slot = s->read_pos + s->read_count;
	201	if (slot >= 16)
	202	slot -= 16;
cc9c9ffc	203	s->read_fifo[slot] = value;
cdbdb648 PB	204	s->read_count++;
	205	s->flags &= ~PL011_FLAG_RXFE;
	206	if (s->cr & 0x10 \|\| s->read_count == 16) {
	207	s->flags \|= PL011_FLAG_RXFF;
	208	}
	209	if (s->read_count == s->read_trigger) {
	210	s->int_level \|= PL011_INT_RX;
	211	pl011_update(s);
	212	}
	213	}
	214
cc9c9ffc AJ	215	static void pl011_receive(void opaque, const uint8_t buf, int size)
	216	{
	217	pl011_put_fifo(opaque, *buf);
	218	}
	219
cdbdb648 PB	220	static void pl011_event(void *opaque, int event)
cdbdb648 PB	221	{
cc9c9ffc AJ	222	if (event == CHR_EVENT_BREAK)
cc9c9ffc AJ	223	pl011_put_fifo(opaque, 0x400);
cdbdb648 PB	224	}
cdbdb648 PB	225
d60efc6b	226	static CPUReadMemoryFunc * const pl011_readfn[] = {
cdbdb648 PB	227	pl011_read,
	228	pl011_read,
	229	pl011_read
	230	};
	231
d60efc6b	232	static CPUWriteMemoryFunc * const pl011_writefn[] = {
cdbdb648 PB	233	pl011_write,
	234	pl011_write,
	235	pl011_write
	236	};
	237
02b68757 JQ	238	static const VMStateDescription vmstate_pl011 = {
	239	.name = "pl011",
	240	.version_id = 1,
	241	.minimum_version_id = 1,
	242	.minimum_version_id_old = 1,
	243	.fields = (VMStateField[]) {
	244	VMSTATE_UINT32(readbuff, pl011_state),
	245	VMSTATE_UINT32(flags, pl011_state),
	246	VMSTATE_UINT32(lcr, pl011_state),
	247	VMSTATE_UINT32(cr, pl011_state),
	248	VMSTATE_UINT32(dmacr, pl011_state),
	249	VMSTATE_UINT32(int_enabled, pl011_state),
	250	VMSTATE_UINT32(int_level, pl011_state),
	251	VMSTATE_UINT32_ARRAY(read_fifo, pl011_state, 16),
	252	VMSTATE_UINT32(ilpr, pl011_state),
	253	VMSTATE_UINT32(ibrd, pl011_state),
	254	VMSTATE_UINT32(fbrd, pl011_state),
	255	VMSTATE_UINT32(ifl, pl011_state),
	256	VMSTATE_INT32(read_pos, pl011_state),
	257	VMSTATE_INT32(read_count, pl011_state),
	258	VMSTATE_INT32(read_trigger, pl011_state),
	259	VMSTATE_END_OF_LIST()
	260	}
	261	};
23e39294	262
81a322d4	263	static int pl011_init(SysBusDevice dev, const unsigned char id)
cdbdb648 PB	264	{
cdbdb648 PB	265	int iomemtype;
a7d518a6	266	pl011_state *s = FROM_SYSBUS(pl011_state, dev);
cdbdb648	267
1eed09cb	268	iomemtype = cpu_register_io_memory(pl011_readfn,
2507c12a AG	269	pl011_writefn, s,
2507c12a AG	270	DEVICE_NATIVE_ENDIAN);
a7d518a6 PB	271	sysbus_init_mmio(dev, 0x1000,iomemtype);
	272	sysbus_init_irq(dev, &s->irq);
	273	s->id = id;
	274	s->chr = qdev_init_chardev(&dev->qdev);
	275
cdbdb648 PB	276	s->read_trigger = 1;
	277	s->ifl = 0x12;
	278	s->cr = 0x300;
	279	s->flags = 0x90;
a7d518a6 PB	280	if (s->chr) {
a7d518a6 PB	281	qemu_chr_add_handlers(s->chr, pl011_can_receive, pl011_receive,
e5b0bc44	282	pl011_event, s);
cdbdb648	283	}
02b68757	284	vmstate_register(&dev->qdev, -1, &vmstate_pl011, s);
81a322d4	285	return 0;
cdbdb648	286	}
a7d518a6	287
81a322d4	288	static int pl011_init_arm(SysBusDevice *dev)
a7d518a6	289	{
81a322d4	290	return pl011_init(dev, pl011_id_arm);
a7d518a6 PB	291	}
a7d518a6 PB	292
81a322d4	293	static int pl011_init_luminary(SysBusDevice *dev)
a7d518a6	294	{
81a322d4	295	return pl011_init(dev, pl011_id_luminary);
a7d518a6 PB	296	}
	297
	298	static void pl011_register_devices(void)
	299	{
	300	sysbus_register_dev("pl011", sizeof(pl011_state),
	301	pl011_init_arm);
	302	sysbus_register_dev("pl011_luminary", sizeof(pl011_state),
	303	pl011_init_luminary);
	304	}
	305
	306	device_init(pl011_register_devices)