hw/timer/arm_mptimer.c - qemu - Git at Google

 /*
  * Private peripheral timer/watchdog blocks for ARM 11MPCore and A9MP
  *
  * Copyright (c) 2006-2007 CodeSourcery.
  * Copyright (c) 2011 Linaro Limited
  * Written by Paul Brook, Peter Maydell
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include "qemu/osdep.h"
 #include "hw/timer/arm_mptimer.h"
 #include "qemu/timer.h"
 #include "qom/cpu.h"

 /* This device implements the per-cpu private timer and watchdog block
  * which is used in both the ARM11MPCore and Cortex-A9MP.
  */

 static inline int get_current_cpu(ARMMPTimerState *s)
 {
     if (current_cpu->cpu_index >= s->num_cpu) {
         hw_error("arm_mptimer: num-cpu %d but this cpu is %d!\n",
                  s->num_cpu, current_cpu->cpu_index);
     }
     return current_cpu->cpu_index;
 }

 static inline void timerblock_update_irq(TimerBlock *tb)
 {
     qemu_set_irq(tb->irq, tb->status && (tb->control & 4));
 }

 /* Return conversion factor from mpcore timer ticks to qemu timer ticks.  */
 static inline uint32_t timerblock_scale(TimerBlock *tb)
 {
     return (((tb->control >> 8) & 0xff) + 1) * 10;
 }

 static void timerblock_reload(TimerBlock *tb, int restart)
 {
     if (tb->count == 0) {
         return;
     }
     if (restart) {
         tb->tick = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     }
     tb->tick += (int64_t)tb->count * timerblock_scale(tb);
     timer_mod(tb->timer, tb->tick);
 }

 static void timerblock_tick(void *opaque)
 {
     TimerBlock *tb = (TimerBlock *)opaque;
     tb->status = 1;
     if (tb->control & 2) {
         tb->count = tb->load;
         timerblock_reload(tb, 0);
     } else {
         tb->count = 0;
     }
     timerblock_update_irq(tb);
 }

 static uint64_t timerblock_read(void *opaque, hwaddr addr,
                                 unsigned size)
 {
     TimerBlock *tb = (TimerBlock *)opaque;
     int64_t val;
     switch (addr) {
     case 0: /* Load */
         return tb->load;
     case 4: /* Counter.  */
         if (((tb->control & 1) == 0) || (tb->count == 0)) {
             return 0;
         }
         /* Slow and ugly, but hopefully won't happen too often.  */
         val = tb->tick - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
         val /= timerblock_scale(tb);
         if (val < 0) {
             val = 0;
         }
         return val;
     case 8: /* Control.  */
         return tb->control;
     case 12: /* Interrupt status.  */
         return tb->status;
     default:
         return 0;
     }
 }

 static void timerblock_write(void *opaque, hwaddr addr,
                              uint64_t value, unsigned size)
 {
     TimerBlock *tb = (TimerBlock *)opaque;
     int64_t old;
     switch (addr) {
     case 0: /* Load */
         tb->load = value;
         /* Fall through.  */
     case 4: /* Counter.  */
         if ((tb->control & 1) && tb->count) {
             /* Cancel the previous timer.  */
             timer_del(tb->timer);
         }
         tb->count = value;
         if (tb->control & 1) {
             timerblock_reload(tb, 1);
         }
         break;
     case 8: /* Control.  */
         old = tb->control;
         tb->control = value;
         if (value & 1) {
             if ((old & 1) && (tb->count != 0)) {
                 /* Do nothing if timer is ticking right now.  */
                 break;
             }
             if (tb->control & 2) {
                 tb->count = tb->load;
             }
             timerblock_reload(tb, 1);
         } else if (old & 1) {
             /* Shutdown the timer.  */
             timer_del(tb->timer);
         }
         break;
     case 12: /* Interrupt status.  */
         tb->status &= ~value;
         timerblock_update_irq(tb);
         break;
     }
 }

 /* Wrapper functions to implement the "read timer/watchdog for
  * the current CPU" memory regions.
  */
 static uint64_t arm_thistimer_read(void *opaque, hwaddr addr,
                                    unsigned size)
 {
     ARMMPTimerState *s = (ARMMPTimerState *)opaque;
     int id = get_current_cpu(s);
     return timerblock_read(&s->timerblock[id], addr, size);
 }

 static void arm_thistimer_write(void *opaque, hwaddr addr,
                                 uint64_t value, unsigned size)
 {
     ARMMPTimerState *s = (ARMMPTimerState *)opaque;
     int id = get_current_cpu(s);
     timerblock_write(&s->timerblock[id], addr, value, size);
 }

 static const MemoryRegionOps arm_thistimer_ops = {
     .read = arm_thistimer_read,
     .write = arm_thistimer_write,
     .valid = {
         .min_access_size = 4,
         .max_access_size = 4,
     },
     .endianness = DEVICE_NATIVE_ENDIAN,
 };

 static const MemoryRegionOps timerblock_ops = {
     .read = timerblock_read,
     .write = timerblock_write,
     .valid = {
         .min_access_size = 4,
         .max_access_size = 4,
     },
     .endianness = DEVICE_NATIVE_ENDIAN,
 };

 static void timerblock_reset(TimerBlock *tb)
 {
     tb->count = 0;
     tb->load = 0;
     tb->control = 0;
     tb->status = 0;
     tb->tick = 0;
     if (tb->timer) {
         timer_del(tb->timer);
     }
 }

 static void arm_mptimer_reset(DeviceState *dev)
 {
     ARMMPTimerState *s = ARM_MPTIMER(dev);
     int i;

     for (i = 0; i < ARRAY_SIZE(s->timerblock); i++) {
         timerblock_reset(&s->timerblock[i]);
     }
 }

 static void arm_mptimer_init(Object *obj)
 {
     ARMMPTimerState *s = ARM_MPTIMER(obj);

     memory_region_init_io(&s->iomem, obj, &arm_thistimer_ops, s,
                           "arm_mptimer_timer", 0x20);
     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
 }

 static void arm_mptimer_realize(DeviceState *dev, Error **errp)
 {
     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
     ARMMPTimerState *s = ARM_MPTIMER(dev);
     int i;

     if (s->num_cpu < 1 || s->num_cpu > ARM_MPTIMER_MAX_CPUS) {
         error_setg(errp, "num-cpu must be between 1 and %d",
                    ARM_MPTIMER_MAX_CPUS);
         return;
     }
     /* We implement one timer block per CPU, and expose multiple MMIO regions:
      *  * region 0 is "timer for this core"
      *  * region 1 is "timer for core 0"
      *  * region 2 is "timer for core 1"
      * and so on.
      * The outgoing interrupt lines are
      *  * timer for core 0
      *  * timer for core 1
      * and so on.
      */
     for (i = 0; i < s->num_cpu; i++) {
         TimerBlock *tb = &s->timerblock[i];
         tb->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, timerblock_tick, tb);
         sysbus_init_irq(sbd, &tb->irq);
         memory_region_init_io(&tb->iomem, OBJECT(s), &timerblock_ops, tb,
                               "arm_mptimer_timerblock", 0x20);
         sysbus_init_mmio(sbd, &tb->iomem);
     }
 }

 static const VMStateDescription vmstate_timerblock = {
     .name = "arm_mptimer_timerblock",
     .version_id = 2,
     .minimum_version_id = 2,
     .fields = (VMStateField[]) {
         VMSTATE_UINT32(count, TimerBlock),
         VMSTATE_UINT32(load, TimerBlock),
         VMSTATE_UINT32(control, TimerBlock),
         VMSTATE_UINT32(status, TimerBlock),
         VMSTATE_INT64(tick, TimerBlock),
         VMSTATE_TIMER_PTR(timer, TimerBlock),
         VMSTATE_END_OF_LIST()
     }
 };

 static const VMStateDescription vmstate_arm_mptimer = {
     .name = "arm_mptimer",
     .version_id = 2,
     .minimum_version_id = 2,
     .fields = (VMStateField[]) {
         VMSTATE_STRUCT_VARRAY_UINT32(timerblock, ARMMPTimerState, num_cpu,
                                      2, vmstate_timerblock, TimerBlock),
         VMSTATE_END_OF_LIST()
     }
 };

 static Property arm_mptimer_properties[] = {
     DEFINE_PROP_UINT32("num-cpu", ARMMPTimerState, num_cpu, 0),
     DEFINE_PROP_END_OF_LIST()
 };

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

     dc->realize = arm_mptimer_realize;
     dc->vmsd = &vmstate_arm_mptimer;
     dc->reset = arm_mptimer_reset;
     dc->props = arm_mptimer_properties;
 }

 static const TypeInfo arm_mptimer_info = {
     .name          = TYPE_ARM_MPTIMER,
     .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(ARMMPTimerState),
     .instance_init = arm_mptimer_init,
     .class_init    = arm_mptimer_class_init,
 };

 static void arm_mptimer_register_types(void)
 {
     type_register_static(&arm_mptimer_info);
 }

 type_init(arm_mptimer_register_types)
	/*
	* Private peripheral timer/watchdog blocks for ARM 11MPCore and A9MP
	*
	* Copyright (c) 2006-2007 CodeSourcery.
	* Copyright (c) 2011 Linaro Limited
	* Written by Paul Brook, Peter Maydell
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include "qemu/osdep.h"
	#include "hw/timer/arm_mptimer.h"
	#include "qemu/timer.h"
	#include "qom/cpu.h"

	/* This device implements the per-cpu private timer and watchdog block
	* which is used in both the ARM11MPCore and Cortex-A9MP.
	*/

	static inline int get_current_cpu(ARMMPTimerState *s)
	{
	if (current_cpu->cpu_index >= s->num_cpu) {
	hw_error("arm_mptimer: num-cpu %d but this cpu is %d!\n",
	s->num_cpu, current_cpu->cpu_index);
	}
	return current_cpu->cpu_index;
	}

	static inline void timerblock_update_irq(TimerBlock *tb)
	{
	qemu_set_irq(tb->irq, tb->status && (tb->control & 4));
	}

	/* Return conversion factor from mpcore timer ticks to qemu timer ticks. */
	static inline uint32_t timerblock_scale(TimerBlock *tb)
	{
	return (((tb->control >> 8) & 0xff) + 1) * 10;
	}

	static void timerblock_reload(TimerBlock *tb, int restart)
	{
	if (tb->count == 0) {
	return;
	}
	if (restart) {
	tb->tick = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
	}
	tb->tick += (int64_t)tb->count * timerblock_scale(tb);
	timer_mod(tb->timer, tb->tick);
	}

	static void timerblock_tick(void *opaque)
	{
	TimerBlock tb = (TimerBlock )opaque;
	tb->status = 1;
	if (tb->control & 2) {
	tb->count = tb->load;
	timerblock_reload(tb, 0);
	} else {
	tb->count = 0;
	}
	timerblock_update_irq(tb);
	}

	static uint64_t timerblock_read(void *opaque, hwaddr addr,
	unsigned size)
	{
	TimerBlock tb = (TimerBlock )opaque;
	int64_t val;
	switch (addr) {
	case 0: /* Load */
	return tb->load;
	case 4: /* Counter. */
	if (((tb->control & 1) == 0) \|\| (tb->count == 0)) {
	return 0;
	}
	/* Slow and ugly, but hopefully won't happen too often. */
	val = tb->tick - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
	val /= timerblock_scale(tb);
	if (val < 0) {
	val = 0;
	}
	return val;
	case 8: /* Control. */
	return tb->control;
	case 12: /* Interrupt status. */
	return tb->status;
	default:
	return 0;
	}
	}

	static void timerblock_write(void *opaque, hwaddr addr,
	uint64_t value, unsigned size)
	{
	TimerBlock tb = (TimerBlock )opaque;
	int64_t old;
	switch (addr) {
	case 0: /* Load */
	tb->load = value;
	/* Fall through. */
	case 4: /* Counter. */
	if ((tb->control & 1) && tb->count) {
	/* Cancel the previous timer. */
	timer_del(tb->timer);
	}
	tb->count = value;
	if (tb->control & 1) {
	timerblock_reload(tb, 1);
	}
	break;
	case 8: /* Control. */
	old = tb->control;
	tb->control = value;
	if (value & 1) {
	if ((old & 1) && (tb->count != 0)) {
	/* Do nothing if timer is ticking right now. */
	break;
	}
	if (tb->control & 2) {
	tb->count = tb->load;
	}
	timerblock_reload(tb, 1);
	} else if (old & 1) {
	/* Shutdown the timer. */
	timer_del(tb->timer);
	}
	break;
	case 12: /* Interrupt status. */
	tb->status &= ~value;
	timerblock_update_irq(tb);
	break;
	}
	}

	/* Wrapper functions to implement the "read timer/watchdog for
	* the current CPU" memory regions.
	*/
	static uint64_t arm_thistimer_read(void *opaque, hwaddr addr,
	unsigned size)
	{
	ARMMPTimerState s = (ARMMPTimerState )opaque;
	int id = get_current_cpu(s);
	return timerblock_read(&s->timerblock[id], addr, size);
	}

	static void arm_thistimer_write(void *opaque, hwaddr addr,
	uint64_t value, unsigned size)
	{
	ARMMPTimerState s = (ARMMPTimerState )opaque;
	int id = get_current_cpu(s);
	timerblock_write(&s->timerblock[id], addr, value, size);
	}

	static const MemoryRegionOps arm_thistimer_ops = {
	.read = arm_thistimer_read,
	.write = arm_thistimer_write,
	.valid = {
	.min_access_size = 4,
	.max_access_size = 4,
	},
	.endianness = DEVICE_NATIVE_ENDIAN,
	};

	static const MemoryRegionOps timerblock_ops = {
	.read = timerblock_read,
	.write = timerblock_write,
	.valid = {
	.min_access_size = 4,
	.max_access_size = 4,
	},
	.endianness = DEVICE_NATIVE_ENDIAN,
	};

	static void timerblock_reset(TimerBlock *tb)
	{
	tb->count = 0;
	tb->load = 0;
	tb->control = 0;
	tb->status = 0;
	tb->tick = 0;
	if (tb->timer) {
	timer_del(tb->timer);
	}
	}

	static void arm_mptimer_reset(DeviceState *dev)
	{
	ARMMPTimerState *s = ARM_MPTIMER(dev);
	int i;

	for (i = 0; i < ARRAY_SIZE(s->timerblock); i++) {
	timerblock_reset(&s->timerblock[i]);
	}
	}

	static void arm_mptimer_init(Object *obj)
	{
	ARMMPTimerState *s = ARM_MPTIMER(obj);

	memory_region_init_io(&s->iomem, obj, &arm_thistimer_ops, s,
	"arm_mptimer_timer", 0x20);
	sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
	}

	static void arm_mptimer_realize(DeviceState dev, Error *errp)
	{
	SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
	ARMMPTimerState *s = ARM_MPTIMER(dev);
	int i;

	if (s->num_cpu < 1 \|\| s->num_cpu > ARM_MPTIMER_MAX_CPUS) {
	error_setg(errp, "num-cpu must be between 1 and %d",
	ARM_MPTIMER_MAX_CPUS);
	return;
	}
	/* We implement one timer block per CPU, and expose multiple MMIO regions:
	* * region 0 is "timer for this core"
	* * region 1 is "timer for core 0"
	* * region 2 is "timer for core 1"
	* and so on.
	* The outgoing interrupt lines are
	* * timer for core 0
	* * timer for core 1
	* and so on.
	*/
	for (i = 0; i < s->num_cpu; i++) {
	TimerBlock *tb = &s->timerblock[i];
	tb->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, timerblock_tick, tb);
	sysbus_init_irq(sbd, &tb->irq);
	memory_region_init_io(&tb->iomem, OBJECT(s), &timerblock_ops, tb,
	"arm_mptimer_timerblock", 0x20);
	sysbus_init_mmio(sbd, &tb->iomem);
	}
	}

	static const VMStateDescription vmstate_timerblock = {
	.name = "arm_mptimer_timerblock",
	.version_id = 2,
	.minimum_version_id = 2,
	.fields = (VMStateField[]) {
	VMSTATE_UINT32(count, TimerBlock),
	VMSTATE_UINT32(load, TimerBlock),
	VMSTATE_UINT32(control, TimerBlock),
	VMSTATE_UINT32(status, TimerBlock),
	VMSTATE_INT64(tick, TimerBlock),
	VMSTATE_TIMER_PTR(timer, TimerBlock),
	VMSTATE_END_OF_LIST()
	}
	};

	static const VMStateDescription vmstate_arm_mptimer = {
	.name = "arm_mptimer",
	.version_id = 2,
	.minimum_version_id = 2,
	.fields = (VMStateField[]) {
	VMSTATE_STRUCT_VARRAY_UINT32(timerblock, ARMMPTimerState, num_cpu,
	2, vmstate_timerblock, TimerBlock),
	VMSTATE_END_OF_LIST()
	}
	};

	static Property arm_mptimer_properties[] = {
	DEFINE_PROP_UINT32("num-cpu", ARMMPTimerState, num_cpu, 0),
	DEFINE_PROP_END_OF_LIST()
	};

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

	dc->realize = arm_mptimer_realize;
	dc->vmsd = &vmstate_arm_mptimer;
	dc->reset = arm_mptimer_reset;
	dc->props = arm_mptimer_properties;
	}

	static const TypeInfo arm_mptimer_info = {
	.name = TYPE_ARM_MPTIMER,
	.parent = TYPE_SYS_BUS_DEVICE,
	.instance_size = sizeof(ARMMPTimerState),
	.instance_init = arm_mptimer_init,
	.class_init = arm_mptimer_class_init,
	};

	static void arm_mptimer_register_types(void)
	{
	type_register_static(&arm_mptimer_info);
	}

	type_init(arm_mptimer_register_types)