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qemu/hw/hpet.c
Anthony Liguori 999e12bbe8 sysbus: apic: ioapic: convert to QEMU Object Model 
This converts three devices because apic and ioapic are subclasses of sysbus.
Converting subclasses independently of their base class is prohibitively hard.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-01-27 10:50:50 -06:00

727 lines
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/*
* High Precisition Event Timer emulation
*
* Copyright (c) 2007 Alexander Graf
* Copyright (c) 2008 IBM Corporation
*
* Authors: Beth Kon <bkon@us.ibm.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* *****************************************************************
*
* This driver attempts to emulate an HPET device in software.
*/
#include "hw.h"
#include "pc.h"
#include "console.h"
#include "qemu-timer.h"
#include "hpet_emul.h"
#include "sysbus.h"
#include "mc146818rtc.h"
//#define HPET_DEBUG
#ifdef HPET_DEBUG
#define DPRINTF printf
#else
#define DPRINTF(...)
#endif
#define HPET_MSI_SUPPORT 0
struct HPETState;
typedef struct HPETTimer { /* timers */
uint8_t tn; /*timer number*/
QEMUTimer *qemu_timer;
struct HPETState *state;
/* Memory-mapped, software visible timer registers */
uint64_t config; /* configuration/cap */
uint64_t cmp; /* comparator */
uint64_t fsb; /* FSB route */
/* Hidden register state */
uint64_t period; /* Last value written to comparator */
uint8_t wrap_flag; /* timer pop will indicate wrap for one-shot 32-bit
* mode. Next pop will be actual timer expiration.
*/
} HPETTimer;
typedef struct HPETState {
SysBusDevice busdev;
MemoryRegion iomem;
uint64_t hpet_offset;
qemu_irq irqs[HPET_NUM_IRQ_ROUTES];
uint32_t flags;
uint8_t rtc_irq_level;
uint8_t num_timers;
HPETTimer timer[HPET_MAX_TIMERS];
/* Memory-mapped, software visible registers */
uint64_t capability; /* capabilities */
uint64_t config; /* configuration */
uint64_t isr; /* interrupt status reg */
uint64_t hpet_counter; /* main counter */
uint8_t hpet_id; /* instance id */
} HPETState;
static uint32_t hpet_in_legacy_mode(HPETState *s)
{
return s->config & HPET_CFG_LEGACY;
}
static uint32_t timer_int_route(struct HPETTimer *timer)
{
return (timer->config & HPET_TN_INT_ROUTE_MASK) >> HPET_TN_INT_ROUTE_SHIFT;
}
static uint32_t timer_fsb_route(HPETTimer *t)
{
return t->config & HPET_TN_FSB_ENABLE;
}
static uint32_t hpet_enabled(HPETState *s)
{
return s->config & HPET_CFG_ENABLE;
}
static uint32_t timer_is_periodic(HPETTimer *t)
{
return t->config & HPET_TN_PERIODIC;
}
static uint32_t timer_enabled(HPETTimer *t)
{
return t->config & HPET_TN_ENABLE;
}
static uint32_t hpet_time_after(uint64_t a, uint64_t b)
{
return ((int32_t)(b) - (int32_t)(a) < 0);
}
static uint32_t hpet_time_after64(uint64_t a, uint64_t b)
{
return ((int64_t)(b) - (int64_t)(a) < 0);
}
static uint64_t ticks_to_ns(uint64_t value)
{
return (muldiv64(value, HPET_CLK_PERIOD, FS_PER_NS));
}
static uint64_t ns_to_ticks(uint64_t value)
{
return (muldiv64(value, FS_PER_NS, HPET_CLK_PERIOD));
}
static uint64_t hpet_fixup_reg(uint64_t new, uint64_t old, uint64_t mask)
{
new &= mask;
new |= old & ~mask;
return new;
}
static int activating_bit(uint64_t old, uint64_t new, uint64_t mask)
{
return (!(old & mask) && (new & mask));
}
static int deactivating_bit(uint64_t old, uint64_t new, uint64_t mask)
{
return ((old & mask) && !(new & mask));
}
static uint64_t hpet_get_ticks(HPETState *s)
{
return ns_to_ticks(qemu_get_clock_ns(vm_clock) + s->hpet_offset);
}
/*
* calculate diff between comparator value and current ticks
*/
static inline uint64_t hpet_calculate_diff(HPETTimer *t, uint64_t current)
{
if (t->config & HPET_TN_32BIT) {
uint32_t diff, cmp;
cmp = (uint32_t)t->cmp;
diff = cmp - (uint32_t)current;
diff = (int32_t)diff > 0 ? diff : (uint32_t)1;
return (uint64_t)diff;
} else {
uint64_t diff, cmp;
cmp = t->cmp;
diff = cmp - current;
diff = (int64_t)diff > 0 ? diff : (uint64_t)1;
return diff;
}
}
static void update_irq(struct HPETTimer *timer, int set)
{
uint64_t mask;
HPETState *s;
int route;
if (timer->tn <= 1 && hpet_in_legacy_mode(timer->state)) {
/* if LegacyReplacementRoute bit is set, HPET specification requires
* timer0 be routed to IRQ0 in NON-APIC or IRQ2 in the I/O APIC,
* timer1 be routed to IRQ8 in NON-APIC or IRQ8 in the I/O APIC.
*/
route = (timer->tn == 0) ? 0 : RTC_ISA_IRQ;
} else {
route = timer_int_route(timer);
}
s = timer->state;
mask = 1 << timer->tn;
if (!set || !timer_enabled(timer) || !hpet_enabled(timer->state)) {
s->isr &= ~mask;
if (!timer_fsb_route(timer)) {
qemu_irq_lower(s->irqs[route]);
}
} else if (timer_fsb_route(timer)) {
stl_le_phys(timer->fsb >> 32, timer->fsb & 0xffffffff);
} else if (timer->config & HPET_TN_TYPE_LEVEL) {
s->isr |= mask;
qemu_irq_raise(s->irqs[route]);
} else {
s->isr &= ~mask;
qemu_irq_pulse(s->irqs[route]);
}
}
static void hpet_pre_save(void *opaque)
{
HPETState *s = opaque;
/* save current counter value */
s->hpet_counter = hpet_get_ticks(s);
}
static int hpet_pre_load(void *opaque)
{
HPETState *s = opaque;
/* version 1 only supports 3, later versions will load the actual value */
s->num_timers = HPET_MIN_TIMERS;
return 0;
}
static int hpet_post_load(void *opaque, int version_id)
{
HPETState *s = opaque;
/* Recalculate the offset between the main counter and guest time */
s->hpet_offset = ticks_to_ns(s->hpet_counter) - qemu_get_clock_ns(vm_clock);
/* Push number of timers into capability returned via HPET_ID */
s->capability &= ~HPET_ID_NUM_TIM_MASK;
s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
/* Derive HPET_MSI_SUPPORT from the capability of the first timer. */
s->flags &= ~(1 << HPET_MSI_SUPPORT);
if (s->timer[0].config & HPET_TN_FSB_CAP) {
s->flags |= 1 << HPET_MSI_SUPPORT;
}
return 0;
}
static const VMStateDescription vmstate_hpet_timer = {
.name = "hpet_timer",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField []) {
VMSTATE_UINT8(tn, HPETTimer),
VMSTATE_UINT64(config, HPETTimer),
VMSTATE_UINT64(cmp, HPETTimer),
VMSTATE_UINT64(fsb, HPETTimer),
VMSTATE_UINT64(period, HPETTimer),
VMSTATE_UINT8(wrap_flag, HPETTimer),
VMSTATE_TIMER(qemu_timer, HPETTimer),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_hpet = {
.name = "hpet",
.version_id = 2,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.pre_save = hpet_pre_save,
.pre_load = hpet_pre_load,
.post_load = hpet_post_load,
.fields = (VMStateField []) {
VMSTATE_UINT64(config, HPETState),
VMSTATE_UINT64(isr, HPETState),
VMSTATE_UINT64(hpet_counter, HPETState),
VMSTATE_UINT8_V(num_timers, HPETState, 2),
VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
vmstate_hpet_timer, HPETTimer),
VMSTATE_END_OF_LIST()
}
};
/*
* timer expiration callback
*/
static void hpet_timer(void *opaque)
{
HPETTimer *t = opaque;
uint64_t diff;
uint64_t period = t->period;
uint64_t cur_tick = hpet_get_ticks(t->state);
if (timer_is_periodic(t) && period != 0) {
if (t->config & HPET_TN_32BIT) {
while (hpet_time_after(cur_tick, t->cmp)) {
t->cmp = (uint32_t)(t->cmp + t->period);
}
} else {
while (hpet_time_after64(cur_tick, t->cmp)) {
t->cmp += period;
}
}
diff = hpet_calculate_diff(t, cur_tick);
qemu_mod_timer(t->qemu_timer,
qemu_get_clock_ns(vm_clock) + (int64_t)ticks_to_ns(diff));
} else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
if (t->wrap_flag) {
diff = hpet_calculate_diff(t, cur_tick);
qemu_mod_timer(t->qemu_timer, qemu_get_clock_ns(vm_clock) +
(int64_t)ticks_to_ns(diff));
t->wrap_flag = 0;
}
}
update_irq(t, 1);
}
static void hpet_set_timer(HPETTimer *t)
{
uint64_t diff;
uint32_t wrap_diff; /* how many ticks until we wrap? */
uint64_t cur_tick = hpet_get_ticks(t->state);
/* whenever new timer is being set up, make sure wrap_flag is 0 */
t->wrap_flag = 0;
diff = hpet_calculate_diff(t, cur_tick);
/* hpet spec says in one-shot 32-bit mode, generate an interrupt when
* counter wraps in addition to an interrupt with comparator match.
*/
if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
wrap_diff = 0xffffffff - (uint32_t)cur_tick;
if (wrap_diff < (uint32_t)diff) {
diff = wrap_diff;
t->wrap_flag = 1;
}
}
qemu_mod_timer(t->qemu_timer,
qemu_get_clock_ns(vm_clock) + (int64_t)ticks_to_ns(diff));
}
static void hpet_del_timer(HPETTimer *t)
{
qemu_del_timer(t->qemu_timer);
update_irq(t, 0);
}
#ifdef HPET_DEBUG
static uint32_t hpet_ram_readb(void *opaque, target_phys_addr_t addr)
{
printf("qemu: hpet_read b at %" PRIx64 "\n", addr);
return 0;
}
static uint32_t hpet_ram_readw(void *opaque, target_phys_addr_t addr)
{
printf("qemu: hpet_read w at %" PRIx64 "\n", addr);
return 0;
}
#endif
static uint64_t hpet_ram_read(void *opaque, target_phys_addr_t addr,
unsigned size)
{
HPETState *s = opaque;
uint64_t cur_tick, index;
DPRINTF("qemu: Enter hpet_ram_readl at %" PRIx64 "\n", addr);
index = addr;
/*address range of all TN regs*/
if (index >= 0x100 && index <= 0x3ff) {
uint8_t timer_id = (addr - 0x100) / 0x20;
HPETTimer *timer = &s->timer[timer_id];
if (timer_id > s->num_timers) {
DPRINTF("qemu: timer id out of range\n");
return 0;
}
switch ((addr - 0x100) % 0x20) {
case HPET_TN_CFG:
return timer->config;
case HPET_TN_CFG + 4: // Interrupt capabilities
return timer->config >> 32;
case HPET_TN_CMP: // comparator register
return timer->cmp;
case HPET_TN_CMP + 4:
return timer->cmp >> 32;
case HPET_TN_ROUTE:
return timer->fsb;
case HPET_TN_ROUTE + 4:
return timer->fsb >> 32;
default:
DPRINTF("qemu: invalid hpet_ram_readl\n");
break;
}
} else {
switch (index) {
case HPET_ID:
return s->capability;
case HPET_PERIOD:
return s->capability >> 32;
case HPET_CFG:
return s->config;
case HPET_CFG + 4:
DPRINTF("qemu: invalid HPET_CFG + 4 hpet_ram_readl\n");
return 0;
case HPET_COUNTER:
if (hpet_enabled(s)) {
cur_tick = hpet_get_ticks(s);
} else {
cur_tick = s->hpet_counter;
}
DPRINTF("qemu: reading counter = %" PRIx64 "\n", cur_tick);
return cur_tick;
case HPET_COUNTER + 4:
if (hpet_enabled(s)) {
cur_tick = hpet_get_ticks(s);
} else {
cur_tick = s->hpet_counter;
}
DPRINTF("qemu: reading counter + 4 = %" PRIx64 "\n", cur_tick);
return cur_tick >> 32;
case HPET_STATUS:
return s->isr;
default:
DPRINTF("qemu: invalid hpet_ram_readl\n");
break;
}
}
return 0;
}
static void hpet_ram_write(void *opaque, target_phys_addr_t addr,
uint64_t value, unsigned size)
{
int i;
HPETState *s = opaque;
uint64_t old_val, new_val, val, index;
DPRINTF("qemu: Enter hpet_ram_writel at %" PRIx64 " = %#x\n", addr, value);
index = addr;
old_val = hpet_ram_read(opaque, addr, 4);
new_val = value;
/*address range of all TN regs*/
if (index >= 0x100 && index <= 0x3ff) {
uint8_t timer_id = (addr - 0x100) / 0x20;
HPETTimer *timer = &s->timer[timer_id];
DPRINTF("qemu: hpet_ram_writel timer_id = %#x\n", timer_id);
if (timer_id > s->num_timers) {
DPRINTF("qemu: timer id out of range\n");
return;
}
switch ((addr - 0x100) % 0x20) {
case HPET_TN_CFG:
DPRINTF("qemu: hpet_ram_writel HPET_TN_CFG\n");
if (activating_bit(old_val, new_val, HPET_TN_FSB_ENABLE)) {
update_irq(timer, 0);
}
val = hpet_fixup_reg(new_val, old_val, HPET_TN_CFG_WRITE_MASK);
timer->config = (timer->config & 0xffffffff00000000ULL) | val;
if (new_val & HPET_TN_32BIT) {
timer->cmp = (uint32_t)timer->cmp;
timer->period = (uint32_t)timer->period;
}
if (activating_bit(old_val, new_val, HPET_TN_ENABLE)) {
hpet_set_timer(timer);
} else if (deactivating_bit(old_val, new_val, HPET_TN_ENABLE)) {
hpet_del_timer(timer);
}
break;
case HPET_TN_CFG + 4: // Interrupt capabilities
DPRINTF("qemu: invalid HPET_TN_CFG+4 write\n");
break;
case HPET_TN_CMP: // comparator register
DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP\n");
if (timer->config & HPET_TN_32BIT) {
new_val = (uint32_t)new_val;
}
if (!timer_is_periodic(timer)
|| (timer->config & HPET_TN_SETVAL)) {
timer->cmp = (timer->cmp & 0xffffffff00000000ULL) | new_val;
}
if (timer_is_periodic(timer)) {
/*
* FIXME: Clamp period to reasonable min value?
* Clamp period to reasonable max value
*/
new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
timer->period =
(timer->period & 0xffffffff00000000ULL) | new_val;
}
timer->config &= ~HPET_TN_SETVAL;
if (hpet_enabled(s)) {
hpet_set_timer(timer);
}
break;
case HPET_TN_CMP + 4: // comparator register high order
DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP + 4\n");
if (!timer_is_periodic(timer)
|| (timer->config & HPET_TN_SETVAL)) {
timer->cmp = (timer->cmp & 0xffffffffULL) | new_val << 32;
} else {
/*
* FIXME: Clamp period to reasonable min value?
* Clamp period to reasonable max value
*/
new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
timer->period =
(timer->period & 0xffffffffULL) | new_val << 32;
}
timer->config &= ~HPET_TN_SETVAL;
if (hpet_enabled(s)) {
hpet_set_timer(timer);
}
break;
case HPET_TN_ROUTE:
timer->fsb = (timer->fsb & 0xffffffff00000000ULL) | new_val;
break;
case HPET_TN_ROUTE + 4:
timer->fsb = (new_val << 32) | (timer->fsb & 0xffffffff);
break;
default:
DPRINTF("qemu: invalid hpet_ram_writel\n");
break;
}
return;
} else {
switch (index) {
case HPET_ID:
return;
case HPET_CFG:
val = hpet_fixup_reg(new_val, old_val, HPET_CFG_WRITE_MASK);
s->config = (s->config & 0xffffffff00000000ULL) | val;
if (activating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
/* Enable main counter and interrupt generation. */
s->hpet_offset =
ticks_to_ns(s->hpet_counter) - qemu_get_clock_ns(vm_clock);
for (i = 0; i < s->num_timers; i++) {
if ((&s->timer[i])->cmp != ~0ULL) {
hpet_set_timer(&s->timer[i]);
}
}
} else if (deactivating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
/* Halt main counter and disable interrupt generation. */
s->hpet_counter = hpet_get_ticks(s);
for (i = 0; i < s->num_timers; i++) {
hpet_del_timer(&s->timer[i]);
}
}
/* i8254 and RTC are disabled when HPET is in legacy mode */
if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
hpet_pit_disable();
qemu_irq_lower(s->irqs[RTC_ISA_IRQ]);
} else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
hpet_pit_enable();
qemu_set_irq(s->irqs[RTC_ISA_IRQ], s->rtc_irq_level);
}
break;
case HPET_CFG + 4:
DPRINTF("qemu: invalid HPET_CFG+4 write\n");
break;
case HPET_STATUS:
val = new_val & s->isr;
for (i = 0; i < s->num_timers; i++) {
if (val & (1 << i)) {
update_irq(&s->timer[i], 0);
}
}
break;
case HPET_COUNTER:
if (hpet_enabled(s)) {
DPRINTF("qemu: Writing counter while HPET enabled!\n");
}
s->hpet_counter =
(s->hpet_counter & 0xffffffff00000000ULL) | value;
DPRINTF("qemu: HPET counter written. ctr = %#x -> %" PRIx64 "\n",
value, s->hpet_counter);
break;
case HPET_COUNTER + 4:
if (hpet_enabled(s)) {
DPRINTF("qemu: Writing counter while HPET enabled!\n");
}
s->hpet_counter =
(s->hpet_counter & 0xffffffffULL) | (((uint64_t)value) << 32);
DPRINTF("qemu: HPET counter + 4 written. ctr = %#x -> %" PRIx64 "\n",
value, s->hpet_counter);
break;
default:
DPRINTF("qemu: invalid hpet_ram_writel\n");
break;
}
}
}
static const MemoryRegionOps hpet_ram_ops = {
.read = hpet_ram_read,
.write = hpet_ram_write,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void hpet_reset(DeviceState *d)
{
HPETState *s = FROM_SYSBUS(HPETState, sysbus_from_qdev(d));
int i;
static int count = 0;
for (i = 0; i < s->num_timers; i++) {
HPETTimer *timer = &s->timer[i];
hpet_del_timer(timer);
timer->cmp = ~0ULL;
timer->config = HPET_TN_PERIODIC_CAP | HPET_TN_SIZE_CAP;
if (s->flags & (1 << HPET_MSI_SUPPORT)) {
timer->config |= HPET_TN_FSB_CAP;
}
/* advertise availability of ioapic inti2 */
timer->config |= 0x00000004ULL << 32;
timer->period = 0ULL;
timer->wrap_flag = 0;
}
s->hpet_counter = 0ULL;
s->hpet_offset = 0ULL;
s->config = 0ULL;
if (count > 0) {
/* we don't enable pit when hpet_reset is first called (by hpet_init)
* because hpet is taking over for pit here. On subsequent invocations,
* hpet_reset is called due to system reset. At this point control must
* be returned to pit until SW reenables hpet.
*/
hpet_pit_enable();
}
hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
hpet_cfg.hpet[s->hpet_id].address = sysbus_from_qdev(d)->mmio[0].addr;
count = 1;
}
static void hpet_handle_rtc_irq(void *opaque, int n, int level)
{
HPETState *s = FROM_SYSBUS(HPETState, opaque);
s->rtc_irq_level = level;
if (!hpet_in_legacy_mode(s)) {
qemu_set_irq(s->irqs[RTC_ISA_IRQ], level);
}
}
static int hpet_init(SysBusDevice *dev)
{
HPETState *s = FROM_SYSBUS(HPETState, dev);
int i;
HPETTimer *timer;
if (hpet_cfg.count == UINT8_MAX) {
/* first instance */
hpet_cfg.count = 0;
}
if (hpet_cfg.count == 8) {
fprintf(stderr, "Only 8 instances of HPET is allowed\n");
return -1;
}
s->hpet_id = hpet_cfg.count++;
for (i = 0; i < HPET_NUM_IRQ_ROUTES; i++) {
sysbus_init_irq(dev, &s->irqs[i]);
}
if (s->num_timers < HPET_MIN_TIMERS) {
s->num_timers = HPET_MIN_TIMERS;
} else if (s->num_timers > HPET_MAX_TIMERS) {
s->num_timers = HPET_MAX_TIMERS;
}
for (i = 0; i < HPET_MAX_TIMERS; i++) {
timer = &s->timer[i];
timer->qemu_timer = qemu_new_timer_ns(vm_clock, hpet_timer, timer);
timer->tn = i;
timer->state = s;
}
/* 64-bit main counter; LegacyReplacementRoute. */
s->capability = 0x8086a001ULL;
s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
s->capability |= ((HPET_CLK_PERIOD) << 32);
qdev_init_gpio_in(&dev->qdev, hpet_handle_rtc_irq, 1);
/* HPET Area */
memory_region_init_io(&s->iomem, &hpet_ram_ops, s, "hpet", 0x400);
sysbus_init_mmio(dev, &s->iomem);
return 0;
}
static Property hpet_device_properties[] = {
DEFINE_PROP_UINT8("timers", HPETState, num_timers, HPET_MIN_TIMERS),
DEFINE_PROP_BIT("msi", HPETState, flags, HPET_MSI_SUPPORT, false),
DEFINE_PROP_END_OF_LIST(),
};
static void hpet_device_class_init(ObjectClass *klass, void *data)
{
SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
k->init = hpet_init;
}
static DeviceInfo hpet_device_info = {
.name = "hpet",
.size = sizeof(HPETState),
.no_user = 1,
.vmsd = &vmstate_hpet,
.reset = hpet_reset,
.props = hpet_device_properties,
.class_init = hpet_device_class_init,
};
static void hpet_register_device(void)
{
sysbus_register_withprop(&hpet_device_info);
}
device_init(hpet_register_device)
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