[qemu.git] / hw / arm_timer.c

/*
 * ARM PrimeCell Timer modules.
 *
 * Copyright (c) 2005-2006 CodeSourcery.
 * Written by Paul Brook
 *
 * This code is licenced under the GPL.
 */

#include "hw.h"
#include "qemu-timer.h"
#include "primecell.h"

/* Common timer implementation.  */

#define TIMER_CTRL_ONESHOT      (1 << 0)
#define TIMER_CTRL_32BIT        (1 << 1)
#define TIMER_CTRL_DIV1         (0 << 2)
#define TIMER_CTRL_DIV16        (1 << 2)
#define TIMER_CTRL_DIV256       (2 << 2)
#define TIMER_CTRL_IE           (1 << 5)
#define TIMER_CTRL_PERIODIC     (1 << 6)
#define TIMER_CTRL_ENABLE       (1 << 7)

typedef struct {
    ptimer_state *timer;
    uint32_t control;
    uint32_t limit;
    int freq;
    int int_level;
    qemu_irq irq;
} arm_timer_state;

/* Check all active timers, and schedule the next timer interrupt.  */

static void arm_timer_update(arm_timer_state *s)
{
    /* Update interrupts.  */
    if (s->int_level && (s->control & TIMER_CTRL_IE)) {
        qemu_irq_raise(s->irq);
    } else {
        qemu_irq_lower(s->irq);
    }
}

static uint32_t arm_timer_read(void *opaque, target_phys_addr_t offset)
{
    arm_timer_state *s = (arm_timer_state *)opaque;

    switch (offset >> 2) {
    case 0: /* TimerLoad */
    case 6: /* TimerBGLoad */
        return s->limit;
    case 1: /* TimerValue */
        return ptimer_get_count(s->timer);
    case 2: /* TimerControl */
        return s->control;
    case 4: /* TimerRIS */
        return s->int_level;
    case 5: /* TimerMIS */
        if ((s->control & TIMER_CTRL_IE) == 0)
            return 0;
        return s->int_level;
    default:
        cpu_abort (cpu_single_env, "arm_timer_read: Bad offset %x\n",
                   (int)offset);
        return 0;
    }
}

/* Reset the timer limit after settings have changed.  */
static void arm_timer_recalibrate(arm_timer_state *s, int reload)
{
    uint32_t limit;

    if ((s->control & TIMER_CTRL_PERIODIC) == 0) {
        /* Free running.  */
        if (s->control & TIMER_CTRL_32BIT)
            limit = 0xffffffff;
        else
            limit = 0xffff;
    } else {
          /* Periodic.  */
          limit = s->limit;
    }
    ptimer_set_limit(s->timer, limit, reload);
}

static void arm_timer_write(void *opaque, target_phys_addr_t offset,
                            uint32_t value)
{
    arm_timer_state *s = (arm_timer_state *)opaque;
    int freq;

    switch (offset >> 2) {
    case 0: /* TimerLoad */
        s->limit = value;
        arm_timer_recalibrate(s, 1);
        break;
    case 1: /* TimerValue */
        /* ??? Linux seems to want to write to this readonly register.
           Ignore it.  */
        break;
    case 2: /* TimerControl */
        if (s->control & TIMER_CTRL_ENABLE) {
            /* Pause the timer if it is running.  This may cause some
               inaccuracy dure to rounding, but avoids a whole lot of other
               messyness.  */
            ptimer_stop(s->timer);
        }
        s->control = value;
        freq = s->freq;
        /* ??? Need to recalculate expiry time after changing divisor.  */
        switch ((value >> 2) & 3) {
        case 1: freq >>= 4; break;
        case 2: freq >>= 8; break;
        }
        arm_timer_recalibrate(s, 0);
        ptimer_set_freq(s->timer, freq);
        if (s->control & TIMER_CTRL_ENABLE) {
            /* Restart the timer if still enabled.  */
            ptimer_run(s->timer, (s->control & TIMER_CTRL_ONESHOT) != 0);
        }
        break;
    case 3: /* TimerIntClr */
        s->int_level = 0;
        break;
    case 6: /* TimerBGLoad */
        s->limit = value;
        arm_timer_recalibrate(s, 0);
        break;
    default:
        cpu_abort (cpu_single_env, "arm_timer_write: Bad offset %x\n",
                   (int)offset);
    }
    arm_timer_update(s);
}

static void arm_timer_tick(void *opaque)
{
    arm_timer_state *s = (arm_timer_state *)opaque;
    s->int_level = 1;
    arm_timer_update(s);
}

static void *arm_timer_init(uint32_t freq, qemu_irq irq)
{
    arm_timer_state *s;
    QEMUBH *bh;

    s = (arm_timer_state *)qemu_mallocz(sizeof(arm_timer_state));
    s->irq = irq;
    s->freq = freq;
    s->control = TIMER_CTRL_IE;

    bh = qemu_bh_new(arm_timer_tick, s);
    s->timer = ptimer_init(bh);
    /* ??? Save/restore.  */
    return s;
}

/* ARM PrimeCell SP804 dual timer module.
   Docs for this device don't seem to be publicly available.  This
   implementation is based on guesswork, the linux kernel sources and the
   Integrator/CP timer modules.  */

typedef struct {
    void *timer[2];
    int level[2];
    uint32_t base;
    qemu_irq irq;
} sp804_state;

/* Merge the IRQs from the two component devices.  */
static void sp804_set_irq(void *opaque, int irq, int level)
{
    sp804_state *s = (sp804_state *)opaque;

    s->level[irq] = level;
    qemu_set_irq(s->irq, s->level[0] || s->level[1]);
}

static uint32_t sp804_read(void *opaque, target_phys_addr_t offset)
{
    sp804_state *s = (sp804_state *)opaque;

    /* ??? Don't know the PrimeCell ID for this device.  */
    offset -= s->base;
    if (offset < 0x20) {
        return arm_timer_read(s->timer[0], offset);
    } else {
        return arm_timer_read(s->timer[1], offset - 0x20);
    }
}

static void sp804_write(void *opaque, target_phys_addr_t offset,
                        uint32_t value)
{
    sp804_state *s = (sp804_state *)opaque;

    offset -= s->base;
    if (offset < 0x20) {
        arm_timer_write(s->timer[0], offset, value);
    } else {
        arm_timer_write(s->timer[1], offset - 0x20, value);
    }
}

static CPUReadMemoryFunc *sp804_readfn[] = {
   sp804_read,
   sp804_read,
   sp804_read
};

static CPUWriteMemoryFunc *sp804_writefn[] = {
   sp804_write,
   sp804_write,
   sp804_write
};

void sp804_init(uint32_t base, qemu_irq irq)
{
    int iomemtype;
    sp804_state *s;
    qemu_irq *qi;

    s = (sp804_state *)qemu_mallocz(sizeof(sp804_state));
    qi = qemu_allocate_irqs(sp804_set_irq, s, 2);
    s->base = base;
    s->irq = irq;
    /* ??? The timers are actually configurable between 32kHz and 1MHz, but
       we don't implement that.  */
    s->timer[0] = arm_timer_init(1000000, qi[0]);
    s->timer[1] = arm_timer_init(1000000, qi[1]);
    iomemtype = cpu_register_io_memory(0, sp804_readfn,
                                       sp804_writefn, s);
    cpu_register_physical_memory(base, 0x00001000, iomemtype);
    /* ??? Save/restore.  */
}


/* Integrator/CP timer module.  */

typedef struct {
    void *timer[3];
    uint32_t base;
} icp_pit_state;

static uint32_t icp_pit_read(void *opaque, target_phys_addr_t offset)
{
    icp_pit_state *s = (icp_pit_state *)opaque;
    int n;

    /* ??? Don't know the PrimeCell ID for this device.  */
    offset -= s->base;
    n = offset >> 8;
    if (n > 3)
        cpu_abort(cpu_single_env, "sp804_read: Bad timer %d\n", n);

    return arm_timer_read(s->timer[n], offset & 0xff);
}

static void icp_pit_write(void *opaque, target_phys_addr_t offset,
                          uint32_t value)
{
    icp_pit_state *s = (icp_pit_state *)opaque;
    int n;

    offset -= s->base;
    n = offset >> 8;
    if (n > 3)
        cpu_abort(cpu_single_env, "sp804_write: Bad timer %d\n", n);

    arm_timer_write(s->timer[n], offset & 0xff, value);
}


static CPUReadMemoryFunc *icp_pit_readfn[] = {
   icp_pit_read,
   icp_pit_read,
   icp_pit_read
};

static CPUWriteMemoryFunc *icp_pit_writefn[] = {
   icp_pit_write,
   icp_pit_write,
   icp_pit_write
};

void icp_pit_init(uint32_t base, qemu_irq *pic, int irq)
{
    int iomemtype;
    icp_pit_state *s;

    s = (icp_pit_state *)qemu_mallocz(sizeof(icp_pit_state));
    s->base = base;
    /* Timer 0 runs at the system clock speed (40MHz).  */
    s->timer[0] = arm_timer_init(40000000, pic[irq]);
    /* The other two timers run at 1MHz.  */
    s->timer[1] = arm_timer_init(1000000, pic[irq + 1]);
    s->timer[2] = arm_timer_init(1000000, pic[irq + 2]);

    iomemtype = cpu_register_io_memory(0, icp_pit_readfn,
                                       icp_pit_writefn, s);
    cpu_register_physical_memory(base, 0x00001000, iomemtype);
    /* ??? Save/restore.  */
}
Commit	Line	Data
5fafdf24	1	/*
cdbdb648 PB	2	* ARM PrimeCell Timer modules.
	3	*
	4	* Copyright (c) 2005-2006 CodeSourcery.
	5	* Written by Paul Brook
	6	*
	7	* This code is licenced under the GPL.
	8	*/
	9
87ecb68b	10	#include "hw.h"
87ecb68b	11	#include "qemu-timer.h"
9596ebb7	12	#include "primecell.h"
cdbdb648 PB	13
	14	/* Common timer implementation. */
	15
	16	#define TIMER_CTRL_ONESHOT (1 << 0)
	17	#define TIMER_CTRL_32BIT (1 << 1)
	18	#define TIMER_CTRL_DIV1 (0 << 2)
	19	#define TIMER_CTRL_DIV16 (1 << 2)
	20	#define TIMER_CTRL_DIV256 (2 << 2)
	21	#define TIMER_CTRL_IE (1 << 5)
	22	#define TIMER_CTRL_PERIODIC (1 << 6)
	23	#define TIMER_CTRL_ENABLE (1 << 7)
	24
	25	typedef struct {
423f0742	26	ptimer_state *timer;
cdbdb648	27	uint32_t control;
cdbdb648	28	uint32_t limit;
cdbdb648 PB	29	int freq;
cdbdb648 PB	30	int int_level;
d537cf6c	31	qemu_irq irq;
cdbdb648 PB	32	} arm_timer_state;
cdbdb648 PB	33
cdbdb648 PB	34	/* Check all active timers, and schedule the next timer interrupt. */
cdbdb648 PB	35
423f0742	36	static void arm_timer_update(arm_timer_state *s)
cdbdb648	37	{
cdbdb648 PB	38	/* Update interrupts. */
cdbdb648 PB	39	if (s->int_level && (s->control & TIMER_CTRL_IE)) {
d537cf6c	40	qemu_irq_raise(s->irq);
cdbdb648	41	} else {
d537cf6c	42	qemu_irq_lower(s->irq);
cdbdb648	43	}
cdbdb648 PB	44	}
cdbdb648 PB	45
9596ebb7	46	static uint32_t arm_timer_read(void *opaque, target_phys_addr_t offset)
cdbdb648 PB	47	{
	48	arm_timer_state s = (arm_timer_state )opaque;
	49
	50	switch (offset >> 2) {
	51	case 0: /* TimerLoad */
	52	case 6: /* TimerBGLoad */
	53	return s->limit;
	54	case 1: /* TimerValue */
423f0742	55	return ptimer_get_count(s->timer);
cdbdb648 PB	56	case 2: /* TimerControl */
	57	return s->control;
	58	case 4: /* TimerRIS */
	59	return s->int_level;
	60	case 5: /* TimerMIS */
	61	if ((s->control & TIMER_CTRL_IE) == 0)
	62	return 0;
	63	return s->int_level;
	64	default:
423f0742 PB	65	cpu_abort (cpu_single_env, "arm_timer_read: Bad offset %x\n",
423f0742 PB	66	(int)offset);
cdbdb648 PB	67	return 0;
	68	}
	69	}
	70
423f0742 PB	71	/* Reset the timer limit after settings have changed. */
	72	static void arm_timer_recalibrate(arm_timer_state *s, int reload)
	73	{
	74	uint32_t limit;
	75
	76	if ((s->control & TIMER_CTRL_PERIODIC) == 0) {
	77	/* Free running. */
	78	if (s->control & TIMER_CTRL_32BIT)
	79	limit = 0xffffffff;
	80	else
	81	limit = 0xffff;
	82	} else {
	83	/* Periodic. */
	84	limit = s->limit;
	85	}
	86	ptimer_set_limit(s->timer, limit, reload);
	87	}
	88
cdbdb648 PB	89	static void arm_timer_write(void *opaque, target_phys_addr_t offset,
	90	uint32_t value)
	91	{
	92	arm_timer_state s = (arm_timer_state )opaque;
423f0742	93	int freq;
cdbdb648	94
cdbdb648 PB	95	switch (offset >> 2) {
	96	case 0: /* TimerLoad */
	97	s->limit = value;
423f0742	98	arm_timer_recalibrate(s, 1);
cdbdb648 PB	99	break;
	100	case 1: /* TimerValue */
	101	/* ??? Linux seems to want to write to this readonly register.
	102	Ignore it. */
	103	break;
	104	case 2: /* TimerControl */
	105	if (s->control & TIMER_CTRL_ENABLE) {
	106	/* Pause the timer if it is running. This may cause some
	107	inaccuracy dure to rounding, but avoids a whole lot of other
	108	messyness. */
423f0742	109	ptimer_stop(s->timer);
cdbdb648 PB	110	}
cdbdb648 PB	111	s->control = value;
423f0742	112	freq = s->freq;
cdbdb648 PB	113	/* ??? Need to recalculate expiry time after changing divisor. */
cdbdb648 PB	114	switch ((value >> 2) & 3) {
423f0742 PB	115	case 1: freq >>= 4; break;
423f0742 PB	116	case 2: freq >>= 8; break;
cdbdb648	117	}
423f0742 PB	118	arm_timer_recalibrate(s, 0);
423f0742 PB	119	ptimer_set_freq(s->timer, freq);
cdbdb648 PB	120	if (s->control & TIMER_CTRL_ENABLE) {
cdbdb648 PB	121	/* Restart the timer if still enabled. */
423f0742	122	ptimer_run(s->timer, (s->control & TIMER_CTRL_ONESHOT) != 0);
cdbdb648 PB	123	}
	124	break;
	125	case 3: /* TimerIntClr */
	126	s->int_level = 0;
	127	break;
	128	case 6: /* TimerBGLoad */
	129	s->limit = value;
423f0742	130	arm_timer_recalibrate(s, 0);
cdbdb648 PB	131	break;
cdbdb648 PB	132	default:
423f0742 PB	133	cpu_abort (cpu_single_env, "arm_timer_write: Bad offset %x\n",
423f0742 PB	134	(int)offset);
cdbdb648	135	}
423f0742	136	arm_timer_update(s);
cdbdb648 PB	137	}
	138
	139	static void arm_timer_tick(void *opaque)
	140	{
423f0742 PB	141	arm_timer_state s = (arm_timer_state )opaque;
	142	s->int_level = 1;
	143	arm_timer_update(s);
cdbdb648 PB	144	}
cdbdb648 PB	145
d537cf6c	146	static void *arm_timer_init(uint32_t freq, qemu_irq irq)
cdbdb648 PB	147	{
cdbdb648 PB	148	arm_timer_state *s;
423f0742	149	QEMUBH *bh;
cdbdb648 PB	150
cdbdb648 PB	151	s = (arm_timer_state *)qemu_mallocz(sizeof(arm_timer_state));
cdbdb648	152	s->irq = irq;
423f0742	153	s->freq = freq;
cdbdb648	154	s->control = TIMER_CTRL_IE;
cdbdb648	155
423f0742 PB	156	bh = qemu_bh_new(arm_timer_tick, s);
423f0742 PB	157	s->timer = ptimer_init(bh);
cdbdb648 PB	158	/* ??? Save/restore. */
	159	return s;
	160	}
	161
	162	/* ARM PrimeCell SP804 dual timer module.
	163	Docs for this device don't seem to be publicly available. This
d85fb99b	164	implementation is based on guesswork, the linux kernel sources and the
cdbdb648 PB	165	Integrator/CP timer modules. */
	166
	167	typedef struct {
cdbdb648 PB	168	void *timer[2];
	169	int level[2];
	170	uint32_t base;
d537cf6c	171	qemu_irq irq;
cdbdb648 PB	172	} sp804_state;
cdbdb648 PB	173
d537cf6c	174	/* Merge the IRQs from the two component devices. */
cdbdb648 PB	175	static void sp804_set_irq(void *opaque, int irq, int level)
	176	{
	177	sp804_state s = (sp804_state )opaque;
	178
	179	s->level[irq] = level;
d537cf6c	180	qemu_set_irq(s->irq, s->level[0] \|\| s->level[1]);
cdbdb648 PB	181	}
	182
	183	static uint32_t sp804_read(void *opaque, target_phys_addr_t offset)
	184	{
	185	sp804_state s = (sp804_state )opaque;
	186
	187	/* ??? Don't know the PrimeCell ID for this device. */
	188	offset -= s->base;
	189	if (offset < 0x20) {
	190	return arm_timer_read(s->timer[0], offset);
	191	} else {
	192	return arm_timer_read(s->timer[1], offset - 0x20);
	193	}
	194	}
	195
	196	static void sp804_write(void *opaque, target_phys_addr_t offset,
	197	uint32_t value)
	198	{
	199	sp804_state s = (sp804_state )opaque;
	200
	201	offset -= s->base;
	202	if (offset < 0x20) {
	203	arm_timer_write(s->timer[0], offset, value);
	204	} else {
	205	arm_timer_write(s->timer[1], offset - 0x20, value);
	206	}
	207	}
	208
	209	static CPUReadMemoryFunc *sp804_readfn[] = {
	210	sp804_read,
	211	sp804_read,
	212	sp804_read
	213	};
	214
	215	static CPUWriteMemoryFunc *sp804_writefn[] = {
	216	sp804_write,
	217	sp804_write,
	218	sp804_write
	219	};
	220
d537cf6c	221	void sp804_init(uint32_t base, qemu_irq irq)
cdbdb648 PB	222	{
	223	int iomemtype;
	224	sp804_state *s;
d537cf6c	225	qemu_irq *qi;
cdbdb648 PB	226
cdbdb648 PB	227	s = (sp804_state *)qemu_mallocz(sizeof(sp804_state));
d537cf6c	228	qi = qemu_allocate_irqs(sp804_set_irq, s, 2);
cdbdb648	229	s->base = base;
cdbdb648 PB	230	s->irq = irq;
	231	/* ??? The timers are actually configurable between 32kHz and 1MHz, but
	232	we don't implement that. */
d537cf6c PB	233	s->timer[0] = arm_timer_init(1000000, qi[0]);
d537cf6c PB	234	s->timer[1] = arm_timer_init(1000000, qi[1]);
cdbdb648 PB	235	iomemtype = cpu_register_io_memory(0, sp804_readfn,
cdbdb648 PB	236	sp804_writefn, s);
187337f8	237	cpu_register_physical_memory(base, 0x00001000, iomemtype);
cdbdb648 PB	238	/* ??? Save/restore. */
	239	}
	240
	241
	242	/* Integrator/CP timer module. */
	243
	244	typedef struct {
	245	void *timer[3];
	246	uint32_t base;
	247	} icp_pit_state;
	248
	249	static uint32_t icp_pit_read(void *opaque, target_phys_addr_t offset)
	250	{
	251	icp_pit_state s = (icp_pit_state )opaque;
	252	int n;
	253
	254	/* ??? Don't know the PrimeCell ID for this device. */
	255	offset -= s->base;
	256	n = offset >> 8;
	257	if (n > 3)
	258	cpu_abort(cpu_single_env, "sp804_read: Bad timer %d\n", n);
	259
	260	return arm_timer_read(s->timer[n], offset & 0xff);
	261	}
	262
	263	static void icp_pit_write(void *opaque, target_phys_addr_t offset,
	264	uint32_t value)
	265	{
	266	icp_pit_state s = (icp_pit_state )opaque;
	267	int n;
	268
	269	offset -= s->base;
	270	n = offset >> 8;
	271	if (n > 3)
	272	cpu_abort(cpu_single_env, "sp804_write: Bad timer %d\n", n);
	273
	274	arm_timer_write(s->timer[n], offset & 0xff, value);
	275	}
	276
	277
	278	static CPUReadMemoryFunc *icp_pit_readfn[] = {
	279	icp_pit_read,
	280	icp_pit_read,
	281	icp_pit_read
	282	};
	283
	284	static CPUWriteMemoryFunc *icp_pit_writefn[] = {
	285	icp_pit_write,
	286	icp_pit_write,
	287	icp_pit_write
	288	};
	289
d537cf6c	290	void icp_pit_init(uint32_t base, qemu_irq *pic, int irq)
cdbdb648 PB	291	{
	292	int iomemtype;
	293	icp_pit_state *s;
	294
	295	s = (icp_pit_state *)qemu_mallocz(sizeof(icp_pit_state));
	296	s->base = base;
	297	/* Timer 0 runs at the system clock speed (40MHz). */
d537cf6c	298	s->timer[0] = arm_timer_init(40000000, pic[irq]);
cdbdb648	299	/* The other two timers run at 1MHz. */
d537cf6c PB	300	s->timer[1] = arm_timer_init(1000000, pic[irq + 1]);
d537cf6c PB	301	s->timer[2] = arm_timer_init(1000000, pic[irq + 2]);
cdbdb648 PB	302
	303	iomemtype = cpu_register_io_memory(0, icp_pit_readfn,
	304	icp_pit_writefn, s);
187337f8	305	cpu_register_physical_memory(base, 0x00001000, iomemtype);
cdbdb648 PB	306	/* ??? Save/restore. */
	307	}
	308