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-rw-r--r--qemu/hw/core/ptimer.c232
1 files changed, 0 insertions, 232 deletions
diff --git a/qemu/hw/core/ptimer.c b/qemu/hw/core/ptimer.c
deleted file mode 100644
index 153c83513..000000000
--- a/qemu/hw/core/ptimer.c
+++ /dev/null
@@ -1,232 +0,0 @@
-/*
- * General purpose implementation of a simple periodic countdown timer.
- *
- * Copyright (c) 2007 CodeSourcery.
- *
- * This code is licensed under the GNU LGPL.
- */
-#include "qemu/osdep.h"
-#include "hw/hw.h"
-#include "qemu/timer.h"
-#include "hw/ptimer.h"
-#include "qemu/host-utils.h"
-#include "sysemu/replay.h"
-
-struct ptimer_state
-{
- uint8_t enabled; /* 0 = disabled, 1 = periodic, 2 = oneshot. */
- uint64_t limit;
- uint64_t delta;
- uint32_t period_frac;
- int64_t period;
- int64_t last_event;
- int64_t next_event;
- QEMUBH *bh;
- QEMUTimer *timer;
-};
-
-/* Use a bottom-half routine to avoid reentrancy issues. */
-static void ptimer_trigger(ptimer_state *s)
-{
- if (s->bh) {
- replay_bh_schedule_event(s->bh);
- }
-}
-
-static void ptimer_reload(ptimer_state *s)
-{
- if (s->delta == 0) {
- ptimer_trigger(s);
- s->delta = s->limit;
- }
- if (s->delta == 0 || s->period == 0) {
- fprintf(stderr, "Timer with period zero, disabling\n");
- s->enabled = 0;
- return;
- }
-
- s->last_event = s->next_event;
- s->next_event = s->last_event + s->delta * s->period;
- if (s->period_frac) {
- s->next_event += ((int64_t)s->period_frac * s->delta) >> 32;
- }
- timer_mod(s->timer, s->next_event);
-}
-
-static void ptimer_tick(void *opaque)
-{
- ptimer_state *s = (ptimer_state *)opaque;
- ptimer_trigger(s);
- s->delta = 0;
- if (s->enabled == 2) {
- s->enabled = 0;
- } else {
- ptimer_reload(s);
- }
-}
-
-uint64_t ptimer_get_count(ptimer_state *s)
-{
- int64_t now;
- uint64_t counter;
-
- if (s->enabled) {
- now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- /* Figure out the current counter value. */
- if (now - s->next_event > 0
- || s->period == 0) {
- /* Prevent timer underflowing if it should already have
- triggered. */
- counter = 0;
- } else {
- uint64_t rem;
- uint64_t div;
- int clz1, clz2;
- int shift;
-
- /* We need to divide time by period, where time is stored in
- rem (64-bit integer) and period is stored in period/period_frac
- (64.32 fixed point).
-
- Doing full precision division is hard, so scale values and
- do a 64-bit division. The result should be rounded down,
- so that the rounding error never causes the timer to go
- backwards.
- */
-
- rem = s->next_event - now;
- div = s->period;
-
- clz1 = clz64(rem);
- clz2 = clz64(div);
- shift = clz1 < clz2 ? clz1 : clz2;
-
- rem <<= shift;
- div <<= shift;
- if (shift >= 32) {
- div |= ((uint64_t)s->period_frac << (shift - 32));
- } else {
- if (shift != 0)
- div |= (s->period_frac >> (32 - shift));
- /* Look at remaining bits of period_frac and round div up if
- necessary. */
- if ((uint32_t)(s->period_frac << shift))
- div += 1;
- }
- counter = rem / div;
- }
- } else {
- counter = s->delta;
- }
- return counter;
-}
-
-void ptimer_set_count(ptimer_state *s, uint64_t count)
-{
- s->delta = count;
- if (s->enabled) {
- s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- ptimer_reload(s);
- }
-}
-
-void ptimer_run(ptimer_state *s, int oneshot)
-{
- if (s->enabled) {
- return;
- }
- if (s->period == 0) {
- fprintf(stderr, "Timer with period zero, disabling\n");
- return;
- }
- s->enabled = oneshot ? 2 : 1;
- s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- ptimer_reload(s);
-}
-
-/* Pause a timer. Note that this may cause it to "lose" time, even if it
- is immediately restarted. */
-void ptimer_stop(ptimer_state *s)
-{
- if (!s->enabled)
- return;
-
- s->delta = ptimer_get_count(s);
- timer_del(s->timer);
- s->enabled = 0;
-}
-
-/* Set counter increment interval in nanoseconds. */
-void ptimer_set_period(ptimer_state *s, int64_t period)
-{
- s->period = period;
- s->period_frac = 0;
- if (s->enabled) {
- s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- ptimer_reload(s);
- }
-}
-
-/* Set counter frequency in Hz. */
-void ptimer_set_freq(ptimer_state *s, uint32_t freq)
-{
- s->period = 1000000000ll / freq;
- s->period_frac = (1000000000ll << 32) / freq;
- if (s->enabled) {
- s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- ptimer_reload(s);
- }
-}
-
-/* Set the initial countdown value. If reload is nonzero then also set
- count = limit. */
-void ptimer_set_limit(ptimer_state *s, uint64_t limit, int reload)
-{
- /*
- * Artificially limit timeout rate to something
- * achievable under QEMU. Otherwise, QEMU spends all
- * its time generating timer interrupts, and there
- * is no forward progress.
- * About ten microseconds is the fastest that really works
- * on the current generation of host machines.
- */
-
- if (!use_icount && limit * s->period < 10000 && s->period) {
- limit = 10000 / s->period;
- }
-
- s->limit = limit;
- if (reload)
- s->delta = limit;
- if (s->enabled && reload) {
- s->next_event = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
- ptimer_reload(s);
- }
-}
-
-const VMStateDescription vmstate_ptimer = {
- .name = "ptimer",
- .version_id = 1,
- .minimum_version_id = 1,
- .fields = (VMStateField[]) {
- VMSTATE_UINT8(enabled, ptimer_state),
- VMSTATE_UINT64(limit, ptimer_state),
- VMSTATE_UINT64(delta, ptimer_state),
- VMSTATE_UINT32(period_frac, ptimer_state),
- VMSTATE_INT64(period, ptimer_state),
- VMSTATE_INT64(last_event, ptimer_state),
- VMSTATE_INT64(next_event, ptimer_state),
- VMSTATE_TIMER_PTR(timer, ptimer_state),
- VMSTATE_END_OF_LIST()
- }
-};
-
-ptimer_state *ptimer_init(QEMUBH *bh)
-{
- ptimer_state *s;
-
- s = (ptimer_state *)g_malloc0(sizeof(ptimer_state));
- s->bh = bh;
- s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ptimer_tick, s);
- return s;
-}