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-rw-r--r--hw/timer/i8254_common.c311
1 files changed, 311 insertions, 0 deletions
diff --git a/hw/timer/i8254_common.c b/hw/timer/i8254_common.c
new file mode 100644
index 0000000000..5342df4a34
--- /dev/null
+++ b/hw/timer/i8254_common.c
@@ -0,0 +1,311 @@
+/*
+ * 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_get_clock_ns(vm_clock));
+}
+
+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_get_clock_ns(vm_clock);
+ s->count = 0x10000;
+ if (i == 0 && !s->irq_disabled) {
+ s->next_transition_time =
+ pit_get_next_transition_time(s, s->count_load_time);
+ }
+ }
+}
+
+static int pit_init_common(ISADevice *dev)
+{
+ PITCommonState *pit = PIT_COMMON(dev);
+ PITCommonClass *c = PIT_COMMON_GET_CLASS(pit);
+ int ret;
+
+ ret = c->init(pit);
+ if (ret < 0) {
+ return ret;
+ }
+
+ isa_register_ioport(dev, &pit->ioports, pit->iobase);
+
+ qdev_set_legacy_instance_id(&dev->qdev, pit->iobase, 2);
+
+ return 0;
+}
+
+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)
+{
+ ISADeviceClass *ic = ISA_DEVICE_CLASS(klass);
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ ic->init = pit_init_common;
+ dc->vmsd = &vmstate_pit_common;
+ dc->no_user = 1;
+}
+
+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);
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-28 13:38:19 +0000