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Diffstat (limited to 'hw/timer/digic-timer.c')
| -rw-r--r-- | hw/timer/digic-timer.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/hw/timer/digic-timer.c b/hw/timer/digic-timer.c new file mode 100644 index 0000000..1fde22c --- /dev/null +++ b/hw/timer/digic-timer.c @@ -0,0 +1,163 @@ +/* + * QEMU model of the Canon DIGIC timer block. + * + * Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com> + * + * This model is based on reverse engineering efforts + * made by CHDK (http://chdk.wikia.com) and + * Magic Lantern (http://www.magiclantern.fm) projects + * contributors. + * + * See "Timer/Clock Module" docs here: + * http://magiclantern.wikia.com/wiki/Register_Map + * + * The QEMU model of the OSTimer in PKUnity SoC by Guan Xuetao + * is used as a template. + * + * 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. + * + */ + +#include "hw/sysbus.h" +#include "hw/ptimer.h" +#include "qemu/main-loop.h" + +#include "hw/timer/digic-timer.h" + +static const VMStateDescription vmstate_digic_timer = { + .name = "digic.timer", + .version_id = 1, + .minimum_version_id = 1, + .minimum_version_id_old = 1, + .fields = (VMStateField[]) { + VMSTATE_PTIMER(ptimer, DigicTimerState), + VMSTATE_UINT32(control, DigicTimerState), + VMSTATE_UINT32(relvalue, DigicTimerState), + VMSTATE_END_OF_LIST() + } +}; + +static void digic_timer_reset(DeviceState *dev) +{ + DigicTimerState *s = DIGIC_TIMER(dev); + + ptimer_stop(s->ptimer); + s->control = 0; + s->relvalue = 0; +} + +static uint64_t digic_timer_read(void *opaque, hwaddr offset, unsigned size) +{ + DigicTimerState *s = opaque; + uint64_t ret = 0; + + switch (offset) { + case DIGIC_TIMER_CONTROL: + ret = s->control; + break; + case DIGIC_TIMER_RELVALUE: + ret = s->relvalue; + break; + case DIGIC_TIMER_VALUE: + ret = ptimer_get_count(s->ptimer) & 0xffff; + break; + default: + qemu_log_mask(LOG_UNIMP, + "digic-timer: read access to unknown register 0x" + TARGET_FMT_plx, offset); + } + + return ret; +} + +static void digic_timer_write(void *opaque, hwaddr offset, + uint64_t value, unsigned size) +{ + DigicTimerState *s = opaque; + + switch (offset) { + case DIGIC_TIMER_CONTROL: + if (value & DIGIC_TIMER_CONTROL_RST) { + digic_timer_reset((DeviceState *)s); + break; + } + + if (value & DIGIC_TIMER_CONTROL_EN) { + ptimer_run(s->ptimer, 0); + } + + s->control = (uint32_t)value; + break; + + case DIGIC_TIMER_RELVALUE: + s->relvalue = extract32(value, 0, 16); + ptimer_set_limit(s->ptimer, s->relvalue, 1); + break; + + case DIGIC_TIMER_VALUE: + break; + + default: + qemu_log_mask(LOG_UNIMP, + "digic-timer: read access to unknown register 0x" + TARGET_FMT_plx, offset); + } +} + +static const MemoryRegionOps digic_timer_ops = { + .read = digic_timer_read, + .write = digic_timer_write, + .impl = { + .min_access_size = 4, + .max_access_size = 4, + }, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void digic_timer_init(Object *obj) +{ + DigicTimerState *s = DIGIC_TIMER(obj); + + s->ptimer = ptimer_init(NULL); + + /* + * FIXME: there is no documentation on Digic timer + * frequency setup so let it always run at 1 MHz + */ + ptimer_set_freq(s->ptimer, 1 * 1000 * 1000); + + memory_region_init_io(&s->iomem, OBJECT(s), &digic_timer_ops, s, + TYPE_DIGIC_TIMER, 0x100); + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem); +} + +static void digic_timer_class_init(ObjectClass *klass, void *class_data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->reset = digic_timer_reset; + dc->vmsd = &vmstate_digic_timer; +} + +static const TypeInfo digic_timer_info = { + .name = TYPE_DIGIC_TIMER, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(DigicTimerState), + .instance_init = digic_timer_init, + .class_init = digic_timer_class_init, +}; + +static void digic_timer_register_type(void) +{ + type_register_static(&digic_timer_info); +} + +type_init(digic_timer_register_type) |
