| /* |
| * QEMU 8253/8254 - common bits of emulated and KVM kernel model |
| * |
| * Copyright (c) 2003-2004 Fabrice Bellard |
| * Copyright (c) 2012 Jan Kiszka, Siemens AG |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| #include "hw/hw.h" |
| #include "hw/i386/pc.h" |
| #include "hw/isa/isa.h" |
| #include "qemu/timer.h" |
| #include "hw/timer/i8254.h" |
| #include "hw/timer/i8254_internal.h" |
| |
| /* val must be 0 or 1 */ |
| void pit_set_gate(ISADevice *dev, int channel, int val) |
| { |
| PITCommonState *pit = PIT_COMMON(dev); |
| PITChannelState *s = &pit->channels[channel]; |
| PITCommonClass *c = PIT_COMMON_GET_CLASS(pit); |
| |
| c->set_channel_gate(pit, s, val); |
| } |
| |
| /* get pit output bit */ |
| int pit_get_out(PITChannelState *s, int64_t current_time) |
| { |
| uint64_t d; |
| int out; |
| |
| d = muldiv64(current_time - s->count_load_time, PIT_FREQ, |
| get_ticks_per_sec()); |
| switch (s->mode) { |
| default: |
| case 0: |
| out = (d >= s->count); |
| break; |
| case 1: |
| out = (d < s->count); |
| break; |
| case 2: |
| if ((d % s->count) == 0 && d != 0) { |
| out = 1; |
| } else { |
| out = 0; |
| } |
| break; |
| case 3: |
| out = (d % s->count) < ((s->count + 1) >> 1); |
| break; |
| case 4: |
| case 5: |
| out = (d == s->count); |
| break; |
| } |
| return out; |
| } |
| |
| /* return -1 if no transition will occur. */ |
| int64_t pit_get_next_transition_time(PITChannelState *s, int64_t current_time) |
| { |
| uint64_t d, next_time, base; |
| int period2; |
| |
| d = muldiv64(current_time - s->count_load_time, PIT_FREQ, |
| get_ticks_per_sec()); |
| switch (s->mode) { |
| default: |
| case 0: |
| case 1: |
| if (d < s->count) { |
| next_time = s->count; |
| } else { |
| return -1; |
| } |
| break; |
| case 2: |
| base = (d / s->count) * s->count; |
| if ((d - base) == 0 && d != 0) { |
| next_time = base + s->count; |
| } else { |
| next_time = base + s->count + 1; |
| } |
| break; |
| case 3: |
| base = (d / s->count) * s->count; |
| period2 = ((s->count + 1) >> 1); |
| if ((d - base) < period2) { |
| next_time = base + period2; |
| } else { |
| next_time = base + s->count; |
| } |
| break; |
| case 4: |
| case 5: |
| if (d < s->count) { |
| next_time = s->count; |
| } else if (d == s->count) { |
| next_time = s->count + 1; |
| } else { |
| return -1; |
| } |
| break; |
| } |
| /* convert to timer units */ |
| next_time = s->count_load_time + muldiv64(next_time, get_ticks_per_sec(), |
| PIT_FREQ); |
| /* fix potential rounding problems */ |
| /* XXX: better solution: use a clock at PIT_FREQ Hz */ |
| if (next_time <= current_time) { |
| next_time = current_time + 1; |
| } |
| return next_time; |
| } |
| |
| void pit_get_channel_info_common(PITCommonState *s, PITChannelState *sc, |
| PITChannelInfo *info) |
| { |
| info->gate = sc->gate; |
| info->mode = sc->mode; |
| info->initial_count = sc->count; |
| info->out = pit_get_out(sc, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)); |
| } |
| |
| void pit_get_channel_info(ISADevice *dev, int channel, PITChannelInfo *info) |
| { |
| PITCommonState *pit = PIT_COMMON(dev); |
| PITChannelState *s = &pit->channels[channel]; |
| PITCommonClass *c = PIT_COMMON_GET_CLASS(pit); |
| |
| c->get_channel_info(pit, s, info); |
| } |
| |
| void pit_reset_common(PITCommonState *pit) |
| { |
| PITChannelState *s; |
| int i; |
| |
| for (i = 0; i < 3; i++) { |
| s = &pit->channels[i]; |
| s->mode = 3; |
| s->gate = (i != 2); |
| s->count_load_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| s->count = 0x10000; |
| if (i == 0 && !s->irq_disabled) { |
| s->next_transition_time = |
| pit_get_next_transition_time(s, s->count_load_time); |
| } |
| } |
| } |
| |
| static void pit_common_realize(DeviceState *dev, Error **errp) |
| { |
| ISADevice *isadev = ISA_DEVICE(dev); |
| PITCommonState *pit = PIT_COMMON(dev); |
| |
| isa_register_ioport(isadev, &pit->ioports, pit->iobase); |
| |
| qdev_set_legacy_instance_id(dev, pit->iobase, 2); |
| } |
| |
| static const VMStateDescription vmstate_pit_channel = { |
| .name = "pit channel", |
| .version_id = 2, |
| .minimum_version_id = 2, |
| .minimum_version_id_old = 2, |
| .fields = (VMStateField[]) { |
| VMSTATE_INT32(count, PITChannelState), |
| VMSTATE_UINT16(latched_count, PITChannelState), |
| VMSTATE_UINT8(count_latched, PITChannelState), |
| VMSTATE_UINT8(status_latched, PITChannelState), |
| VMSTATE_UINT8(status, PITChannelState), |
| VMSTATE_UINT8(read_state, PITChannelState), |
| VMSTATE_UINT8(write_state, PITChannelState), |
| VMSTATE_UINT8(write_latch, PITChannelState), |
| VMSTATE_UINT8(rw_mode, PITChannelState), |
| VMSTATE_UINT8(mode, PITChannelState), |
| VMSTATE_UINT8(bcd, PITChannelState), |
| VMSTATE_UINT8(gate, PITChannelState), |
| VMSTATE_INT64(count_load_time, PITChannelState), |
| VMSTATE_INT64(next_transition_time, PITChannelState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static int pit_load_old(QEMUFile *f, void *opaque, int version_id) |
| { |
| PITCommonState *pit = opaque; |
| PITCommonClass *c = PIT_COMMON_GET_CLASS(pit); |
| PITChannelState *s; |
| int i; |
| |
| if (version_id != 1) { |
| return -EINVAL; |
| } |
| |
| for (i = 0; i < 3; i++) { |
| s = &pit->channels[i]; |
| s->count = qemu_get_be32(f); |
| qemu_get_be16s(f, &s->latched_count); |
| qemu_get_8s(f, &s->count_latched); |
| qemu_get_8s(f, &s->status_latched); |
| qemu_get_8s(f, &s->status); |
| qemu_get_8s(f, &s->read_state); |
| qemu_get_8s(f, &s->write_state); |
| qemu_get_8s(f, &s->write_latch); |
| qemu_get_8s(f, &s->rw_mode); |
| qemu_get_8s(f, &s->mode); |
| qemu_get_8s(f, &s->bcd); |
| qemu_get_8s(f, &s->gate); |
| s->count_load_time = qemu_get_be64(f); |
| s->irq_disabled = 0; |
| if (i == 0) { |
| s->next_transition_time = qemu_get_be64(f); |
| } |
| } |
| if (c->post_load) { |
| c->post_load(pit); |
| } |
| return 0; |
| } |
| |
| static void pit_dispatch_pre_save(void *opaque) |
| { |
| PITCommonState *s = opaque; |
| PITCommonClass *c = PIT_COMMON_GET_CLASS(s); |
| |
| if (c->pre_save) { |
| c->pre_save(s); |
| } |
| } |
| |
| static int pit_dispatch_post_load(void *opaque, int version_id) |
| { |
| PITCommonState *s = opaque; |
| PITCommonClass *c = PIT_COMMON_GET_CLASS(s); |
| |
| if (c->post_load) { |
| c->post_load(s); |
| } |
| return 0; |
| } |
| |
| static const VMStateDescription vmstate_pit_common = { |
| .name = "i8254", |
| .version_id = 3, |
| .minimum_version_id = 2, |
| .minimum_version_id_old = 1, |
| .load_state_old = pit_load_old, |
| .pre_save = pit_dispatch_pre_save, |
| .post_load = pit_dispatch_post_load, |
| .fields = (VMStateField[]) { |
| VMSTATE_UINT32_V(channels[0].irq_disabled, PITCommonState, 3), |
| VMSTATE_STRUCT_ARRAY(channels, PITCommonState, 3, 2, |
| vmstate_pit_channel, PITChannelState), |
| VMSTATE_INT64(channels[0].next_transition_time, |
| PITCommonState), /* formerly irq_timer */ |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static void pit_common_class_init(ObjectClass *klass, void *data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| |
| dc->realize = pit_common_realize; |
| dc->vmsd = &vmstate_pit_common; |
| /* |
| * Reason: unlike ordinary ISA devices, the PIT may need to be |
| * wired to the HPET, and because of that, some wiring is always |
| * done by board code. |
| */ |
| dc->cannot_instantiate_with_device_add_yet = true; |
| } |
| |
| static const TypeInfo pit_common_type = { |
| .name = TYPE_PIT_COMMON, |
| .parent = TYPE_ISA_DEVICE, |
| .instance_size = sizeof(PITCommonState), |
| .class_size = sizeof(PITCommonClass), |
| .class_init = pit_common_class_init, |
| .abstract = true, |
| }; |
| |
| static void register_devices(void) |
| { |
| type_register_static(&pit_common_type); |
| } |
| |
| type_init(register_devices); |