[mirror_qemu.git] / hw / watchdog / cmsdk-apb-watchdog.c

/*
 * ARM CMSDK APB watchdog emulation
 *
 * Copyright (c) 2018 Linaro Limited
 * Written by Peter Maydell
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 or
 *  (at your option) any later version.
 */

/*
 * This is a model of the "APB watchdog" which is part of the Cortex-M
 * System Design Kit (CMSDK) and documented in the Cortex-M System
 * Design Kit Technical Reference Manual (ARM DDI0479C):
 * https://developer.arm.com/products/system-design/system-design-kits/cortex-m-system-design-kit
 *
 * We also support the variant of this device found in the TI
 * Stellaris/Luminary boards and documented in:
 * http://www.ti.com/lit/ds/symlink/lm3s6965.pdf
 */

#include "qemu/osdep.h"
#include "qemu/log.h"
#include "trace.h"
#include "qapi/error.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
#include "sysemu/watchdog.h"
#include "hw/sysbus.h"
#include "hw/irq.h"
#include "hw/registerfields.h"
#include "hw/watchdog/cmsdk-apb-watchdog.h"
#include "migration/vmstate.h"

REG32(WDOGLOAD, 0x0)
REG32(WDOGVALUE, 0x4)
REG32(WDOGCONTROL, 0x8)
    FIELD(WDOGCONTROL, INTEN, 0, 1)
    FIELD(WDOGCONTROL, RESEN, 1, 1)
#define R_WDOGCONTROL_VALID_MASK (R_WDOGCONTROL_INTEN_MASK | \
                                  R_WDOGCONTROL_RESEN_MASK)
REG32(WDOGINTCLR, 0xc)
REG32(WDOGRIS, 0x10)
    FIELD(WDOGRIS, INT, 0, 1)
REG32(WDOGMIS, 0x14)
REG32(WDOGTEST, 0x418) /* only in Stellaris/Luminary version of the device */
REG32(WDOGLOCK, 0xc00)
#define WDOG_UNLOCK_VALUE 0x1ACCE551
REG32(WDOGITCR, 0xf00)
    FIELD(WDOGITCR, ENABLE, 0, 1)
#define R_WDOGITCR_VALID_MASK R_WDOGITCR_ENABLE_MASK
REG32(WDOGITOP, 0xf04)
    FIELD(WDOGITOP, WDOGRES, 0, 1)
    FIELD(WDOGITOP, WDOGINT, 1, 1)
#define R_WDOGITOP_VALID_MASK (R_WDOGITOP_WDOGRES_MASK | \
                               R_WDOGITOP_WDOGINT_MASK)
REG32(PID4, 0xfd0)
REG32(PID5, 0xfd4)
REG32(PID6, 0xfd8)
REG32(PID7, 0xfdc)
REG32(PID0, 0xfe0)
REG32(PID1, 0xfe4)
REG32(PID2, 0xfe8)
REG32(PID3, 0xfec)
REG32(CID0, 0xff0)
REG32(CID1, 0xff4)
REG32(CID2, 0xff8)
REG32(CID3, 0xffc)

/* PID/CID values */
static const uint32_t cmsdk_apb_watchdog_id[] = {
    0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
    0x24, 0xb8, 0x1b, 0x00, /* PID0..PID3 */
    0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
};

static const uint32_t luminary_watchdog_id[] = {
    0x00, 0x00, 0x00, 0x00, /* PID4..PID7 */
    0x05, 0x18, 0x18, 0x01, /* PID0..PID3 */
    0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
};

static bool cmsdk_apb_watchdog_intstatus(CMSDKAPBWatchdog *s)
{
    /* Return masked interrupt status */
    return s->intstatus && (s->control & R_WDOGCONTROL_INTEN_MASK);
}

static bool cmsdk_apb_watchdog_resetstatus(CMSDKAPBWatchdog *s)
{
    /* Return masked reset status */
    return s->resetstatus && (s->control & R_WDOGCONTROL_RESEN_MASK);
}

static void cmsdk_apb_watchdog_update(CMSDKAPBWatchdog *s)
{
    bool wdogint;
    bool wdogres;

    if (s->itcr) {
        /*
         * Not checking that !s->is_luminary since s->itcr can't be written
         * when s->is_luminary in the first place.
         */
        wdogint = s->itop & R_WDOGITOP_WDOGINT_MASK;
        wdogres = s->itop & R_WDOGITOP_WDOGRES_MASK;
    } else {
        wdogint = cmsdk_apb_watchdog_intstatus(s);
        wdogres = cmsdk_apb_watchdog_resetstatus(s);
    }

    qemu_set_irq(s->wdogint, wdogint);
    if (wdogres) {
        watchdog_perform_action();
    }
}

static uint64_t cmsdk_apb_watchdog_read(void *opaque, hwaddr offset,
                                        unsigned size)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);
    uint64_t r;

    switch (offset) {
    case A_WDOGLOAD:
        r = ptimer_get_limit(s->timer);
        break;
    case A_WDOGVALUE:
        r = ptimer_get_count(s->timer);
        break;
    case A_WDOGCONTROL:
        r = s->control;
        break;
    case A_WDOGRIS:
        r = s->intstatus;
        break;
    case A_WDOGMIS:
        r = cmsdk_apb_watchdog_intstatus(s);
        break;
    case A_WDOGLOCK:
        r = s->lock;
        break;
    case A_WDOGITCR:
        if (s->is_luminary) {
            goto bad_offset;
        }
        r = s->itcr;
        break;
    case A_PID4 ... A_CID3:
        r = s->id[(offset - A_PID4) / 4];
        break;
    case A_WDOGINTCLR:
    case A_WDOGITOP:
        if (s->is_luminary) {
            goto bad_offset;
        }
        qemu_log_mask(LOG_GUEST_ERROR,
                      "CMSDK APB watchdog read: read of WO offset %x\n",
                      (int)offset);
        r = 0;
        break;
    case A_WDOGTEST:
        if (!s->is_luminary) {
            goto bad_offset;
        }
        qemu_log_mask(LOG_UNIMP,
                      "Luminary watchdog read: stall not implemented\n");
        r = 0;
        break;
    default:
bad_offset:
        qemu_log_mask(LOG_GUEST_ERROR,
                      "CMSDK APB watchdog read: bad offset %x\n", (int)offset);
        r = 0;
        break;
    }
    trace_cmsdk_apb_watchdog_read(offset, r, size);
    return r;
}

static void cmsdk_apb_watchdog_write(void *opaque, hwaddr offset,
                                     uint64_t value, unsigned size)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);

    trace_cmsdk_apb_watchdog_write(offset, value, size);

    if (s->lock && offset != A_WDOGLOCK) {
        /* Write access is disabled via WDOGLOCK */
        qemu_log_mask(LOG_GUEST_ERROR,
                      "CMSDK APB watchdog write: write to locked watchdog\n");
        return;
    }

    switch (offset) {
    case A_WDOGLOAD:
        /*
         * Reset the load value and the current count, and make sure
         * we're counting.
         */
        ptimer_set_limit(s->timer, value, 1);
        ptimer_run(s->timer, 0);
        break;
    case A_WDOGCONTROL:
        if (s->is_luminary && 0 != (R_WDOGCONTROL_INTEN_MASK & s->control)) {
            /*
             * The Luminary version of this device ignores writes to
             * this register after the guest has enabled interrupts
             * (so they can only be disabled again via reset).
             */
            break;
        }
        s->control = value & R_WDOGCONTROL_VALID_MASK;
        cmsdk_apb_watchdog_update(s);
        break;
    case A_WDOGINTCLR:
        s->intstatus = 0;
        ptimer_set_count(s->timer, ptimer_get_limit(s->timer));
        cmsdk_apb_watchdog_update(s);
        break;
    case A_WDOGLOCK:
        s->lock = (value != WDOG_UNLOCK_VALUE);
        break;
    case A_WDOGITCR:
        if (s->is_luminary) {
            goto bad_offset;
        }
        s->itcr = value & R_WDOGITCR_VALID_MASK;
        cmsdk_apb_watchdog_update(s);
        break;
    case A_WDOGITOP:
        if (s->is_luminary) {
            goto bad_offset;
        }
        s->itop = value & R_WDOGITOP_VALID_MASK;
        cmsdk_apb_watchdog_update(s);
        break;
    case A_WDOGVALUE:
    case A_WDOGRIS:
    case A_WDOGMIS:
    case A_PID4 ... A_CID3:
        qemu_log_mask(LOG_GUEST_ERROR,
                      "CMSDK APB watchdog write: write to RO offset 0x%x\n",
                      (int)offset);
        break;
    case A_WDOGTEST:
        if (!s->is_luminary) {
            goto bad_offset;
        }
        qemu_log_mask(LOG_UNIMP,
                      "Luminary watchdog write: stall not implemented\n");
        break;
    default:
bad_offset:
        qemu_log_mask(LOG_GUEST_ERROR,
                      "CMSDK APB watchdog write: bad offset 0x%x\n",
                      (int)offset);
        break;
    }
}

static const MemoryRegionOps cmsdk_apb_watchdog_ops = {
    .read = cmsdk_apb_watchdog_read,
    .write = cmsdk_apb_watchdog_write,
    .endianness = DEVICE_LITTLE_ENDIAN,
    /* byte/halfword accesses are just zero-padded on reads and writes */
    .impl.min_access_size = 4,
    .impl.max_access_size = 4,
    .valid.min_access_size = 1,
    .valid.max_access_size = 4,
};

static void cmsdk_apb_watchdog_tick(void *opaque)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);

    if (!s->intstatus) {
        /* Count expired for the first time: raise interrupt */
        s->intstatus = R_WDOGRIS_INT_MASK;
    } else {
        /* Count expired for the second time: raise reset and stop clock */
        s->resetstatus = 1;
        ptimer_stop(s->timer);
    }
    cmsdk_apb_watchdog_update(s);
}

static void cmsdk_apb_watchdog_reset(DeviceState *dev)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(dev);

    trace_cmsdk_apb_watchdog_reset();
    s->control = 0;
    s->intstatus = 0;
    s->lock = 0;
    s->itcr = 0;
    s->itop = 0;
    s->resetstatus = 0;
    /* Set the limit and the count */
    ptimer_set_limit(s->timer, 0xffffffff, 1);
    ptimer_run(s->timer, 0);
}

static void cmsdk_apb_watchdog_init(Object *obj)
{
    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(obj);

    memory_region_init_io(&s->iomem, obj, &cmsdk_apb_watchdog_ops,
                          s, "cmsdk-apb-watchdog", 0x1000);
    sysbus_init_mmio(sbd, &s->iomem);
    sysbus_init_irq(sbd, &s->wdogint);

    s->is_luminary = false;
    s->id = cmsdk_apb_watchdog_id;
}

static void cmsdk_apb_watchdog_realize(DeviceState *dev, Error **errp)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(dev);
    QEMUBH *bh;

    if (s->wdogclk_frq == 0) {
        error_setg(errp,
                   "CMSDK APB watchdog: wdogclk-frq property must be set");
        return;
    }

    bh = qemu_bh_new(cmsdk_apb_watchdog_tick, s);
    s->timer = ptimer_init(bh,
                           PTIMER_POLICY_WRAP_AFTER_ONE_PERIOD |
                           PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT |
                           PTIMER_POLICY_NO_IMMEDIATE_RELOAD |
                           PTIMER_POLICY_NO_COUNTER_ROUND_DOWN);

    ptimer_set_freq(s->timer, s->wdogclk_frq);
}

static const VMStateDescription cmsdk_apb_watchdog_vmstate = {
    .name = "cmsdk-apb-watchdog",
    .version_id = 1,
    .minimum_version_id = 1,
    .fields = (VMStateField[]) {
        VMSTATE_PTIMER(timer, CMSDKAPBWatchdog),
        VMSTATE_UINT32(control, CMSDKAPBWatchdog),
        VMSTATE_UINT32(intstatus, CMSDKAPBWatchdog),
        VMSTATE_UINT32(lock, CMSDKAPBWatchdog),
        VMSTATE_UINT32(itcr, CMSDKAPBWatchdog),
        VMSTATE_UINT32(itop, CMSDKAPBWatchdog),
        VMSTATE_UINT32(resetstatus, CMSDKAPBWatchdog),
        VMSTATE_END_OF_LIST()
    }
};

static Property cmsdk_apb_watchdog_properties[] = {
    DEFINE_PROP_UINT32("wdogclk-frq", CMSDKAPBWatchdog, wdogclk_frq, 0),
    DEFINE_PROP_END_OF_LIST(),
};

static void cmsdk_apb_watchdog_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);

    dc->realize = cmsdk_apb_watchdog_realize;
    dc->vmsd = &cmsdk_apb_watchdog_vmstate;
    dc->reset = cmsdk_apb_watchdog_reset;
    dc->props = cmsdk_apb_watchdog_properties;
}

static const TypeInfo cmsdk_apb_watchdog_info = {
    .name = TYPE_CMSDK_APB_WATCHDOG,
    .parent = TYPE_SYS_BUS_DEVICE,
    .instance_size = sizeof(CMSDKAPBWatchdog),
    .instance_init = cmsdk_apb_watchdog_init,
    .class_init = cmsdk_apb_watchdog_class_init,
};

static void luminary_watchdog_init(Object *obj)
{
    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(obj);

    s->is_luminary = true;
    s->id = luminary_watchdog_id;
}

static const TypeInfo luminary_watchdog_info = {
    .name = TYPE_LUMINARY_WATCHDOG,
    .parent = TYPE_CMSDK_APB_WATCHDOG,
    .instance_init = luminary_watchdog_init
};

static void cmsdk_apb_watchdog_register_types(void)
{
    type_register_static(&cmsdk_apb_watchdog_info);
    type_register_static(&luminary_watchdog_info);
}

type_init(cmsdk_apb_watchdog_register_types);
Commit	Line	Data
050c2ea0 PM	1	/*
	2	* ARM CMSDK APB watchdog emulation
	3	*
	4	* Copyright (c) 2018 Linaro Limited
	5	* Written by Peter Maydell
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 or
	9	* (at your option) any later version.
	10	*/
	11
	12	/*
	13	* This is a model of the "APB watchdog" which is part of the Cortex-M
	14	* System Design Kit (CMSDK) and documented in the Cortex-M System
	15	* Design Kit Technical Reference Manual (ARM DDI0479C):
	16	* https://developer.arm.com/products/system-design/system-design-kits/cortex-m-system-design-kit
566528f8 MH	17	*
	18	* We also support the variant of this device found in the TI
	19	* Stellaris/Luminary boards and documented in:
	20	* http://www.ti.com/lit/ds/symlink/lm3s6965.pdf
050c2ea0 PM	21	*/
	22
	23	#include "qemu/osdep.h"
	24	#include "qemu/log.h"
	25	#include "trace.h"
	26	#include "qapi/error.h"
	27	#include "qemu/main-loop.h"
0b8fa32f	28	#include "qemu/module.h"
050c2ea0 PM	29	#include "sysemu/watchdog.h"
050c2ea0 PM	30	#include "hw/sysbus.h"
64552b6b	31	#include "hw/irq.h"
050c2ea0 PM	32	#include "hw/registerfields.h"
050c2ea0 PM	33	#include "hw/watchdog/cmsdk-apb-watchdog.h"
d6454270	34	#include "migration/vmstate.h"
050c2ea0 PM	35
	36	REG32(WDOGLOAD, 0x0)
	37	REG32(WDOGVALUE, 0x4)
	38	REG32(WDOGCONTROL, 0x8)
	39	FIELD(WDOGCONTROL, INTEN, 0, 1)
	40	FIELD(WDOGCONTROL, RESEN, 1, 1)
	41	#define R_WDOGCONTROL_VALID_MASK (R_WDOGCONTROL_INTEN_MASK \| \
	42	R_WDOGCONTROL_RESEN_MASK)
	43	REG32(WDOGINTCLR, 0xc)
	44	REG32(WDOGRIS, 0x10)
	45	FIELD(WDOGRIS, INT, 0, 1)
	46	REG32(WDOGMIS, 0x14)
566528f8	47	REG32(WDOGTEST, 0x418) /* only in Stellaris/Luminary version of the device */
050c2ea0 PM	48	REG32(WDOGLOCK, 0xc00)
	49	#define WDOG_UNLOCK_VALUE 0x1ACCE551
	50	REG32(WDOGITCR, 0xf00)
	51	FIELD(WDOGITCR, ENABLE, 0, 1)
	52	#define R_WDOGITCR_VALID_MASK R_WDOGITCR_ENABLE_MASK
	53	REG32(WDOGITOP, 0xf04)
	54	FIELD(WDOGITOP, WDOGRES, 0, 1)
	55	FIELD(WDOGITOP, WDOGINT, 1, 1)
	56	#define R_WDOGITOP_VALID_MASK (R_WDOGITOP_WDOGRES_MASK \| \
	57	R_WDOGITOP_WDOGINT_MASK)
	58	REG32(PID4, 0xfd0)
	59	REG32(PID5, 0xfd4)
	60	REG32(PID6, 0xfd8)
	61	REG32(PID7, 0xfdc)
	62	REG32(PID0, 0xfe0)
	63	REG32(PID1, 0xfe4)
	64	REG32(PID2, 0xfe8)
	65	REG32(PID3, 0xfec)
	66	REG32(CID0, 0xff0)
	67	REG32(CID1, 0xff4)
	68	REG32(CID2, 0xff8)
	69	REG32(CID3, 0xffc)
	70
	71	/* PID/CID values */
566528f8	72	static const uint32_t cmsdk_apb_watchdog_id[] = {
050c2ea0 PM	73	0x04, 0x00, 0x00, 0x00, /* PID4..PID7 */
	74	0x24, 0xb8, 0x1b, 0x00, /* PID0..PID3 */
	75	0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
	76	};
	77
566528f8 MH	78	static const uint32_t luminary_watchdog_id[] = {
	79	0x00, 0x00, 0x00, 0x00, /* PID4..PID7 */
	80	0x05, 0x18, 0x18, 0x01, /* PID0..PID3 */
	81	0x0d, 0xf0, 0x05, 0xb1, /* CID0..CID3 */
	82	};
	83
050c2ea0 PM	84	static bool cmsdk_apb_watchdog_intstatus(CMSDKAPBWatchdog *s)
	85	{
	86	/* Return masked interrupt status */
	87	return s->intstatus && (s->control & R_WDOGCONTROL_INTEN_MASK);
	88	}
	89
	90	static bool cmsdk_apb_watchdog_resetstatus(CMSDKAPBWatchdog *s)
	91	{
	92	/* Return masked reset status */
	93	return s->resetstatus && (s->control & R_WDOGCONTROL_RESEN_MASK);
	94	}
	95
	96	static void cmsdk_apb_watchdog_update(CMSDKAPBWatchdog *s)
	97	{
	98	bool wdogint;
	99	bool wdogres;
	100
	101	if (s->itcr) {
566528f8 MH	102	/*
	103	* Not checking that !s->is_luminary since s->itcr can't be written
	104	* when s->is_luminary in the first place.
	105	*/
050c2ea0 PM	106	wdogint = s->itop & R_WDOGITOP_WDOGINT_MASK;
	107	wdogres = s->itop & R_WDOGITOP_WDOGRES_MASK;
	108	} else {
	109	wdogint = cmsdk_apb_watchdog_intstatus(s);
	110	wdogres = cmsdk_apb_watchdog_resetstatus(s);
	111	}
	112
	113	qemu_set_irq(s->wdogint, wdogint);
	114	if (wdogres) {
	115	watchdog_perform_action();
	116	}
	117	}
	118
	119	static uint64_t cmsdk_apb_watchdog_read(void *opaque, hwaddr offset,
	120	unsigned size)
	121	{
	122	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);
	123	uint64_t r;
	124
	125	switch (offset) {
	126	case A_WDOGLOAD:
	127	r = ptimer_get_limit(s->timer);
	128	break;
	129	case A_WDOGVALUE:
	130	r = ptimer_get_count(s->timer);
	131	break;
	132	case A_WDOGCONTROL:
	133	r = s->control;
	134	break;
	135	case A_WDOGRIS:
	136	r = s->intstatus;
	137	break;
	138	case A_WDOGMIS:
	139	r = cmsdk_apb_watchdog_intstatus(s);
	140	break;
	141	case A_WDOGLOCK:
	142	r = s->lock;
	143	break;
	144	case A_WDOGITCR:
566528f8 MH	145	if (s->is_luminary) {
	146	goto bad_offset;
	147	}
050c2ea0 PM	148	r = s->itcr;
	149	break;
	150	case A_PID4 ... A_CID3:
566528f8	151	r = s->id[(offset - A_PID4) / 4];
050c2ea0 PM	152	break;
	153	case A_WDOGINTCLR:
	154	case A_WDOGITOP:
566528f8 MH	155	if (s->is_luminary) {
	156	goto bad_offset;
	157	}
050c2ea0 PM	158	qemu_log_mask(LOG_GUEST_ERROR,
	159	"CMSDK APB watchdog read: read of WO offset %x\n",
	160	(int)offset);
	161	r = 0;
	162	break;
566528f8 MH	163	case A_WDOGTEST:
	164	if (!s->is_luminary) {
	165	goto bad_offset;
	166	}
	167	qemu_log_mask(LOG_UNIMP,
	168	"Luminary watchdog read: stall not implemented\n");
	169	r = 0;
	170	break;
050c2ea0	171	default:
566528f8	172	bad_offset:
050c2ea0 PM	173	qemu_log_mask(LOG_GUEST_ERROR,
	174	"CMSDK APB watchdog read: bad offset %x\n", (int)offset);
	175	r = 0;
	176	break;
	177	}
	178	trace_cmsdk_apb_watchdog_read(offset, r, size);
	179	return r;
	180	}
	181
	182	static void cmsdk_apb_watchdog_write(void *opaque, hwaddr offset,
	183	uint64_t value, unsigned size)
	184	{
	185	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);
	186
	187	trace_cmsdk_apb_watchdog_write(offset, value, size);
	188
	189	if (s->lock && offset != A_WDOGLOCK) {
	190	/* Write access is disabled via WDOGLOCK */
	191	qemu_log_mask(LOG_GUEST_ERROR,
	192	"CMSDK APB watchdog write: write to locked watchdog\n");
	193	return;
	194	}
	195
	196	switch (offset) {
	197	case A_WDOGLOAD:
	198	/*
	199	* Reset the load value and the current count, and make sure
	200	* we're counting.
	201	*/
	202	ptimer_set_limit(s->timer, value, 1);
	203	ptimer_run(s->timer, 0);
	204	break;
	205	case A_WDOGCONTROL:
566528f8 MH	206	if (s->is_luminary && 0 != (R_WDOGCONTROL_INTEN_MASK & s->control)) {
	207	/*
	208	* The Luminary version of this device ignores writes to
	209	* this register after the guest has enabled interrupts
	210	* (so they can only be disabled again via reset).
	211	*/
	212	break;
	213	}
050c2ea0 PM	214	s->control = value & R_WDOGCONTROL_VALID_MASK;
	215	cmsdk_apb_watchdog_update(s);
	216	break;
	217	case A_WDOGINTCLR:
	218	s->intstatus = 0;
	219	ptimer_set_count(s->timer, ptimer_get_limit(s->timer));
	220	cmsdk_apb_watchdog_update(s);
	221	break;
	222	case A_WDOGLOCK:
	223	s->lock = (value != WDOG_UNLOCK_VALUE);
	224	break;
	225	case A_WDOGITCR:
566528f8 MH	226	if (s->is_luminary) {
	227	goto bad_offset;
	228	}
050c2ea0 PM	229	s->itcr = value & R_WDOGITCR_VALID_MASK;
	230	cmsdk_apb_watchdog_update(s);
	231	break;
	232	case A_WDOGITOP:
566528f8 MH	233	if (s->is_luminary) {
	234	goto bad_offset;
	235	}
050c2ea0 PM	236	s->itop = value & R_WDOGITOP_VALID_MASK;
	237	cmsdk_apb_watchdog_update(s);
	238	break;
	239	case A_WDOGVALUE:
	240	case A_WDOGRIS:
	241	case A_WDOGMIS:
	242	case A_PID4 ... A_CID3:
	243	qemu_log_mask(LOG_GUEST_ERROR,
	244	"CMSDK APB watchdog write: write to RO offset 0x%x\n",
	245	(int)offset);
	246	break;
566528f8 MH	247	case A_WDOGTEST:
	248	if (!s->is_luminary) {
	249	goto bad_offset;
	250	}
	251	qemu_log_mask(LOG_UNIMP,
	252	"Luminary watchdog write: stall not implemented\n");
	253	break;
050c2ea0	254	default:
566528f8	255	bad_offset:
050c2ea0 PM	256	qemu_log_mask(LOG_GUEST_ERROR,
	257	"CMSDK APB watchdog write: bad offset 0x%x\n",
	258	(int)offset);
	259	break;
	260	}
	261	}
	262
	263	static const MemoryRegionOps cmsdk_apb_watchdog_ops = {
	264	.read = cmsdk_apb_watchdog_read,
	265	.write = cmsdk_apb_watchdog_write,
	266	.endianness = DEVICE_LITTLE_ENDIAN,
	267	/* byte/halfword accesses are just zero-padded on reads and writes */
	268	.impl.min_access_size = 4,
	269	.impl.max_access_size = 4,
	270	.valid.min_access_size = 1,
	271	.valid.max_access_size = 4,
	272	};
	273
	274	static void cmsdk_apb_watchdog_tick(void *opaque)
	275	{
	276	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);
	277
	278	if (!s->intstatus) {
	279	/* Count expired for the first time: raise interrupt */
	280	s->intstatus = R_WDOGRIS_INT_MASK;
	281	} else {
	282	/* Count expired for the second time: raise reset and stop clock */
	283	s->resetstatus = 1;
	284	ptimer_stop(s->timer);
	285	}
	286	cmsdk_apb_watchdog_update(s);
	287	}
	288
	289	static void cmsdk_apb_watchdog_reset(DeviceState *dev)
	290	{
	291	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(dev);
	292
	293	trace_cmsdk_apb_watchdog_reset();
	294	s->control = 0;
	295	s->intstatus = 0;
	296	s->lock = 0;
	297	s->itcr = 0;
	298	s->itop = 0;
	299	s->resetstatus = 0;
	300	/* Set the limit and the count */
	301	ptimer_set_limit(s->timer, 0xffffffff, 1);
	302	ptimer_run(s->timer, 0);
	303	}
	304
	305	static void cmsdk_apb_watchdog_init(Object *obj)
	306	{
	307	SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
	308	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(obj);
	309
	310	memory_region_init_io(&s->iomem, obj, &cmsdk_apb_watchdog_ops,
	311	s, "cmsdk-apb-watchdog", 0x1000);
	312	sysbus_init_mmio(sbd, &s->iomem);
	313	sysbus_init_irq(sbd, &s->wdogint);
566528f8 MH	314
	315	s->is_luminary = false;
	316	s->id = cmsdk_apb_watchdog_id;
050c2ea0 PM	317	}
	318
	319	static void cmsdk_apb_watchdog_realize(DeviceState dev, Error *errp)
	320	{
	321	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(dev);
	322	QEMUBH *bh;
	323
	324	if (s->wdogclk_frq == 0) {
	325	error_setg(errp,
	326	"CMSDK APB watchdog: wdogclk-frq property must be set");
	327	return;
	328	}
	329
	330	bh = qemu_bh_new(cmsdk_apb_watchdog_tick, s);
	331	s->timer = ptimer_init(bh,
	332	PTIMER_POLICY_WRAP_AFTER_ONE_PERIOD \|
	333	PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT \|
	334	PTIMER_POLICY_NO_IMMEDIATE_RELOAD \|
	335	PTIMER_POLICY_NO_COUNTER_ROUND_DOWN);
	336
	337	ptimer_set_freq(s->timer, s->wdogclk_frq);
	338	}
	339
	340	static const VMStateDescription cmsdk_apb_watchdog_vmstate = {
	341	.name = "cmsdk-apb-watchdog",
	342	.version_id = 1,
	343	.minimum_version_id = 1,
	344	.fields = (VMStateField[]) {
	345	VMSTATE_PTIMER(timer, CMSDKAPBWatchdog),
	346	VMSTATE_UINT32(control, CMSDKAPBWatchdog),
	347	VMSTATE_UINT32(intstatus, CMSDKAPBWatchdog),
	348	VMSTATE_UINT32(lock, CMSDKAPBWatchdog),
	349	VMSTATE_UINT32(itcr, CMSDKAPBWatchdog),
	350	VMSTATE_UINT32(itop, CMSDKAPBWatchdog),
	351	VMSTATE_UINT32(resetstatus, CMSDKAPBWatchdog),
	352	VMSTATE_END_OF_LIST()
	353	}
	354	};
	355
	356	static Property cmsdk_apb_watchdog_properties[] = {
	357	DEFINE_PROP_UINT32("wdogclk-frq", CMSDKAPBWatchdog, wdogclk_frq, 0),
	358	DEFINE_PROP_END_OF_LIST(),
	359	};
	360
	361	static void cmsdk_apb_watchdog_class_init(ObjectClass klass, void data)
	362	{
	363	DeviceClass *dc = DEVICE_CLASS(klass);
	364
	365	dc->realize = cmsdk_apb_watchdog_realize;
	366	dc->vmsd = &cmsdk_apb_watchdog_vmstate;
	367	dc->reset = cmsdk_apb_watchdog_reset;
	368	dc->props = cmsdk_apb_watchdog_properties;
	369	}
	370
	371	static const TypeInfo cmsdk_apb_watchdog_info = {
	372	.name = TYPE_CMSDK_APB_WATCHDOG,
	373	.parent = TYPE_SYS_BUS_DEVICE,
	374	.instance_size = sizeof(CMSDKAPBWatchdog),
	375	.instance_init = cmsdk_apb_watchdog_init,
	376	.class_init = cmsdk_apb_watchdog_class_init,
	377	};
	378
566528f8 MH	379	static void luminary_watchdog_init(Object *obj)
	380	{
	381	CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(obj);
	382
	383	s->is_luminary = true;
	384	s->id = luminary_watchdog_id;
	385	}
	386
	387	static const TypeInfo luminary_watchdog_info = {
	388	.name = TYPE_LUMINARY_WATCHDOG,
	389	.parent = TYPE_CMSDK_APB_WATCHDOG,
	390	.instance_init = luminary_watchdog_init
	391	};
	392
050c2ea0 PM	393	static void cmsdk_apb_watchdog_register_types(void)
	394	{
	395	type_register_static(&cmsdk_apb_watchdog_info);
566528f8	396	type_register_static(&luminary_watchdog_info);
050c2ea0 PM	397	}
	398
	399	type_init(cmsdk_apb_watchdog_register_types);